WorldWideScience

Sample records for spleen uptake colloid

  1. Altered splenic uptake in the biodistribution of 99MTc-stannous fluoride colloid in rats

    International Nuclear Information System (INIS)

    Tsopelas, C.; Bartholomeusz, F.D.L.; Smith, E.; Drew, P.A.

    2003-01-01

    Full text: Radiolabelled white cells have found extensive application in nuclear medicine practice, with use in detecting sites of infection and inflammation. In 99M Tc-stannous flu- oride (SnF2) colloid labelled leucocyte scans high liver and spleen activity is visualised, limiting the potential of this technique. This is thought to be due to free or unphagocytosed 99M Tc-SnF2 colloid in the preparation. Labelling white cells with 99M Tc-SnF2 depends upon phagocytic engulfment of this colloid. Non-phagocy-tosed colloid may be a cause of increased splenic activity. Our aims were to assess if it were possible to reduce liver/spleen uptake of 99M Tc-SnF2 colloid in a rat model, by administering unlabelled SnF2 colloid before injection of radiocolloid, in a modification of the standard British Pharmacopoeial test. The biodistribution of 99M Tc-SnF2 colloid alone gave 85.4% uptake in the liver and 7.6% in the spleen. A pre-injection of 26.5μg cold SnF2 and then 99M Tc-SnF2 colloid resulted in decreased spleen uptake by 43%. A higher (52μg) pre-injection dose gave a greater decrease in splenic uptake by 53%. When ex vivo opsonised 99M Tc-SnF2 colloid was administered, both liver and spleen uptake was not reduced. From these results, a pre-injection of unlabelled SnF2 substantially depletes the circulating opsonin concentration, thereby decreasing the opsonisation rate of unopsonised 99M Tc-SnF2 colloid. The limiting factor is likely to be the amount of opsonisation in the plasma rather than phagocytic capacity of the macrophages of liver and spleen. In conclusion these results suggest that a pre-injection of cold stannous fluoride may reduce splenic uptake in 99M Tc-SnF2 colloid labelled white cell scans. Copyright (2003) The Australian and New Zealand Society of Nuclear Medicine Inc

  2. Tc-99m sulfur colloid spleen imaging following splenic artery and vein resection for pancreas organ donation

    International Nuclear Information System (INIS)

    Kuni, C.C.; Crass, J.R.; Du Cret, R.P.; Boudreau, R.J.; Loken, M.K.

    1987-01-01

    The authors retrospectively studied the records and Tc-99m sulfur colloid (TSC) splenic artery and vein resection for donation to HLA-compatible relatives. Of 37 patients with postoperative TSC studies, four had no postoperative splenic abnormalities. Nineteen of the abnormal TSC studies were followed with TSC studies 2 weeks to 14 months later; three showed no change, seven showed improvements,and ten became normal. One patient required splenectomy 2 days after pancreatectomy for splenic infarction; her TSC study showed no uptake. These data suggest that the spleen usually survives splenic artery and vein resection. Absent splenic TSC uptake raises the possibility of splenic infarction but usually improves

  3. Sup (99m) Tc-MDP accumulation and absence of concentration of sup (99m) Tc-sulfur colloid in the spleen

    International Nuclear Information System (INIS)

    Calegaro, J.U.M.; Carvalho, A.C.M. de; Ulyssea, R.

    1984-01-01

    A case of a nine years old girl with sickle cell anemia, that showed splenic accumulation of sup (99m) Tc-MDP during bone scintigraphy is reported. On the other side, the scan with sup (99m) Tc-sulfur colloid showed no uptake in the spleen. These findings are discussed with a brief review of the pertinent literature. (Author) [pt

  4. Lung uptake of /sup 99m/Tc--sulfur colloid in falciparum malaria: case report

    Energy Technology Data Exchange (ETDEWEB)

    Ziessman, H.A.

    1976-09-01

    Increased lung uptake of /sup 99m/Tc-sulfur colloid was seen during liver scanning in a patient with falciparum malaria. This finding was due to the enhanced activity of the phagocytic cells of the reticuloendothelial system in the liver, spleen, and lung found in human and experimental malaria. Similar findings in other clinical situations and the relevant literature are reviewed.

  5. Spleen

    International Nuclear Information System (INIS)

    Freedman, G.S.

    1975-01-01

    Careful examination of the left upper quadrant of the pediatric patient will usually disclose the presence or absence of an enlarged spleen. Although the spleen has a wide variation in weight and mobility, the normal spleen rarely extends below the left costal margin. While the presence of a palpable spleen is usually of pathological significance, the wide variation in splenic weight and position may make the detection of splenomegaly difficult on routine physical examination. When present, it may be difficult to differentiate the enlarged spleen from other palpable masses in the left upper quadrant. For these reasons, radionuclide imaging of the spleen has become a simple and valuable method for precisely locating and establishing the accurate size of functioning splenic tissue. The size and weight of the spleen can be approximated by direct measurement from the scan; normal values have been established based on the splenic length and the age and weight of the child. The diagnostic usefulness of radionuclide s []anning of the spleen in lymphoma, leukemia, other malignancies, anemia and other blood dyscrasias, infectious diseases, granuloma, and cysts is discussed. (CH)

  6. Quantitative uptake of colloidal particles by cell cultures

    Energy Technology Data Exchange (ETDEWEB)

    Feliu, Neus [Department of Physics, Philipps University Marburg, Marburg (Germany); Department for Clinical Science, Intervention and Technology (CLINTEC),Karolinska Institutet, Stockholm (Sweden); Hühn, Jonas; Zyuzin, Mikhail V.; Ashraf, Sumaira; Valdeperez, Daniel; Masood, Atif [Department of Physics, Philipps University Marburg, Marburg (Germany); Said, Alaa Hassan [Department of Physics, Philipps University Marburg, Marburg (Germany); Physics Department, Faculty of Science, South Valley University (Egypt); Escudero, Alberto [Department of Physics, Philipps University Marburg, Marburg (Germany); Instituto de Ciencia de Materiales de Sevilla, CSIC — Universidad de Sevilla, Seville (Spain); Pelaz, Beatriz [Department of Physics, Philipps University Marburg, Marburg (Germany); Gonzalez, Elena [Department of Physics, Philipps University Marburg, Marburg (Germany); University of Vigo, Vigo (Spain); Duarte, Miguel A. Correa [University of Vigo, Vigo (Spain); Roy, Sathi [Department of Physics, Philipps University Marburg, Marburg (Germany); Chakraborty, Indranath [Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, IL (United States); Lim, Mei L.; Sjöqvist, Sebastian [Department for Clinical Science, Intervention and Technology (CLINTEC),Karolinska Institutet, Stockholm (Sweden); Jungebluth, Philipp [Department of Thoracic Surgery, Thoraxklinik, Heidelberg University, Heidelberg (Germany); Parak, Wolfgang J., E-mail: wolfgang.parak@physik.uni-marburg.de [Department of Physics, Philipps University Marburg, Marburg (Germany); CIC biomaGUNE, San Sebastian (Spain)

    2016-10-15

    The use of nanotechnologies involving nano- and microparticles has increased tremendously in the recent past. There are various beneficial characteristics that make particles attractive for a wide range of technologies. However, colloidal particles on the other hand can potentially be harmful for humans and environment. Today, complete understanding of the interaction of colloidal particles with biological systems still remains a challenge. Indeed, their uptake, effects, and final cell cycle including their life span fate and degradation in biological systems are not fully understood. This is mainly due to the complexity of multiple parameters which need to be taken in consideration to perform the nanosafety research. Therefore, we will provide an overview of the common denominators and ideas to achieve universal metrics to assess their safety. The review discusses aspects including how biological media could change the physicochemical properties of colloids, how colloids are endocytosed by cells, how to distinguish between internalized versus membrane-attached colloids, possible correlation of cellular uptake of colloids with their physicochemical properties, and how the colloidal stability of colloids may vary upon cell internalization. In conclusion three main statements are given. First, in typically exposure scenarios only part of the colloids associated with cells are internalized while a significant part remain outside cells attached to their membrane. For quantitative uptake studies false positive counts in the form of only adherent but not internalized colloids have to be avoided. pH sensitive fluorophores attached to the colloids, which can discriminate between acidic endosomal/lysosomal and neutral extracellular environment around colloids offer a possible solution. Second, the metrics selected for uptake studies is of utmost importance. Counting the internalized colloids by number or by volume may lead to significantly different results. Third, colloids

  7. Scannographic appearance of increased colloid uptake in the left liver lobe (Case presentation)

    International Nuclear Information System (INIS)

    Tadzher, Isak S.; Josifovska, Tatjana; Popgjorcheva, Daniela

    1996-01-01

    Incidentally increased uptake of Tc-99m sulfur colloid was found in scannographic images in the whole left liver lobe in all positions (PA, AP, DL, LL). The patient, a 60-year-old woman, was three years earlier cholocystecomized and had since occasional pain in the right upper abdominal quadrant due to biliary dyskinesia. Accessory spleen tissue was seen as well in the inferior lineal pole, probably presenting Shurer's phenomenon of 'lienis in liene' thus augmenting the serendipity of the scanographic findings. Imaging of the accessory spleen with heat denaturated spherocytes - Tc-99m confirmed the lienal structure of the tissue with preserved red pulp trabecular trapping mechanism in addition to phagocytic function of lineal Kupffer cells (in white pulp). Mebrofenin-Tc-99m (IDA-agent) showed in our patient normal distribution in both liver lobes contrary to focal nodular hyperplasia and adenoma of the liver where IDA-radio- pharmaceuticals have delayed clearance due to abnormal biliary canaliculi. In our patient uptake, distribution, excretion and liver washout of mebrofenin-Tc-99m was found to be normal. This is in favor of an exclusive, solitary increase of the number of Kupffer cells confined to the whole left lobe of the liver. Increased colloid uptake in the left liver lobe is dependent on a greater number of Kupffer cells pro volume than in the right lobe. (Author)

  8. Influence of colloid particle profile on sentinel lymph node uptake

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Nunez, Eutimio Gustavo [Radiopharmacy Center, Institute of Energetic and Nuclear Research, Sao Paulo, SP 05508-000 (Brazil)], E-mail: eutimiocu@yahoo.com; Linkowski Faintuch, Bluma; Teodoro, Rodrigo; Pereira Wiecek, Danielle [Radiopharmacy Center, Institute of Energetic and Nuclear Research, Sao Paulo, SP 05508-000 (Brazil); Martinelli, Jose Roberto [Center of Materials Science and Technology, Institute of Energetic and Nuclear Research, Sao Paulo, SP 05508-000 (Brazil); Gomes da Silva, Natanael; Castanheira, Claudia E. [Radiopharmacy Center, Institute of Energetic and Nuclear Research, Sao Paulo, SP 05508-000 (Brazil); Santos de Oliveira Filho, Renato [Faculty of Medicine, Federal University of Sao Paulo, SP 04020-041 (Brazil); Pasqualini, Roberto [CIS bio international, Research and Development, Gif sur Yvette, 91192 (France)

    2009-10-15

    Introduction: Particle size of colloids employed for sentinel lymph node (LN) detection is not well studied. This investigation aimed to correlate particle size and distribution of different products with LN uptake. Methods: All agents (colloidal tin, dextran, phytate and colloidal rhenium sulfide) were labeled with {sup 99m}Tc according to manufacturer's instructions. Sizing of particles was carried out on electron micrographs using Image Tool for Windows (Version 2.0). Biodistribution studies in main excretion organs as well as in popliteal LN were performed in male Wistar rats [30 and 90 min post injection (p.i.)]. The injected dose was 0.1 ml (37 MBq) in the footpad of the left posterior limb. Dynamic images (0-15 min p.i.) as well as static ones (30 and 90 min) were acquired in gamma camera. Results: Popliteal LN was clearly reached by all products. Nevertheless, particle size remarkably influenced node uptake. Colloidal rhenium sulfide, with the smallest diameter (5.1x10{sup -3}{+-}3.9x10{sup -3} {mu}m), permitted the best result [2.72{+-}0.64 percent injected dose (%ID) at 90 min]. Phytate displayed small particles (<15 {mu}m) with favorable uptake (1.02{+-}0.14%ID). Dextran (21.4{+-}12.8 {mu}m) and colloidal tin (39.0{+-}8.3 {mu}m) were less effective (0.55{+-}0.14 and 0.06{+-}0.03%ID respectively). Particle distribution also tended to influence results. When asymmetric, it was associated with biphasic uptake which increased over time; conversely, symmetric distribution (colloidal tin) was consistent with a constant pattern. Conclusion: The results are suggesting that particle size and symmetry may interfere with LN radiopharmaceutical uptake.

  9. Normal Uptake of 11C-Acetate in Pancreas, Liver, Spleen, and Suprarenal Gland in PET

    Directory of Open Access Journals (Sweden)

    Bogdan Malkowski

    2017-01-01

    Full Text Available Purpose. C11-Acetate is radiotracer being considered an alternative to 18F-fluorodeoxyglucose. Evaluation of C11-acetate biodistribution in human parenchymal organs is described. Methods and Materials. 60 consecutive patients referred to C11-acetate PET CT suspected of renal or prostate cancer relapse with negative results (no recurrent tumor were included in the study. Acquisition from the base of skull to upper thigh was made 20 min after i.v. injection of 720 MBq of C11-acetate. The distribution was evaluated by measuring the uptake in pancreas (uncinate process and body separately, liver, spleen, and left suprarenal gland. Clinical data of included patients showed no abnormalities in these organs. Results. Biodistributions of C11-acetate radiotracer were compared in different organs. Standardized uptake values of 11C-acetate were significantly higher in pancreatic parenchyma (SUV mean 6,4 than in liver (SUV mean 3,3, spleen (SUV mean 4,5, or suprarenal gland (SUV mean 2,7 tissues. No significant difference was found between pancreatic head (SUV mean 6,4 and body (SUV mean 5,9 uptake. In case of all aforementioned organs, there were no differences either between both sexes or between formerly diagnosed tumors (renal and prostate. Conclusions. Evaluation of C11-acetate uptake differences in parenchymal organs will allow establishing normal patterns of distribution. High pancreatic uptake may be used in quantitative assessment of organ function in diffuse nonneoplastic pathology.

  10. Diagnostic value of 18F-FDG uptake by spleen in acute radiation disease

    Directory of Open Access Journals (Sweden)

    Shao-jie WU

    2015-07-01

    Full Text Available Objective To investigate whether 18F-FDG uptake can be applied in dosimetry to facilitate a rapid and accurate evaluation of individual radiation dosage after a nuclear accident. Methods Forty-eight Tibetan minipigs were randomly assigned into 6 groups, i.e., 0, 1, 2, 5, 8 and 11Gy groups. Animals in all except 0Gy group received total body irradiation (TBI with a 8MV X centrifugal linear accelerator, and 18F-FDG combined positron-emission tomography and computed tomography (PET/CT were carried out before TBI, and also at 6, 24 and 72h after receiving TBI in different doses ranging from 1 to 11Gy. Spleen tissues and blood samples were collected for histological examination, apoptosis, and routine blood analysis. Results Mean standardized uptake values (SUVs of the spleen showed significant differences between experimental groups and control group. The spleen SUVs at 6h post-irradiation showed significant correlation with radiation dose; Spearman's correlation coefficient was 0.95(P<0.01. Histopathological observations showed that the degree of splenic damage was proportional to the radiation dose. Moreover, flow cytometry revealed that apoptosis was one of the major forms of splenic lymphocyte death. Conclusion In the Tibetan minipig model, it was shown that radiation doses bear a close relationship with the 18F-FDG uptake of spleen. This finding suggests that 18F-FDG PET/CT may be useful for the rapid detection of individual radiation dosage after acute radiation disease (ARD. DOI: 10.11855/j.issn.0577-7402.2015.07.08

  11. 99 mTc-sulphur-colloid and heat-denatured 99mTc-labelled red cell scans demonstrating a giant intrapelvic spleen in a girl after splenectomy

    International Nuclear Information System (INIS)

    Kao, P.F.; Tzen, K.Y.; Tsai, M.F.; Lin, J.N.

    2001-01-01

    A 17 x 12 x 5-cm giant intrapelvic mass in a 14-year-old girl is reported. This mass developed 6 years after a splenectomy for splenic torsion. The heat-denatured 99 m Tc-labelled red cell scan and 99 m Tc- sulphur-colloid scan confirmed the specific red cell sequestration function and reticuloendothelial activity in the giant intrapelvic spleen. The size and development of the giant intrapelvic spleen are unusual. The usefulness of functional images to diagnosis the nature of the intrapelvic mass is well demonstrated. (orig.)

  12. Radioactive colloids

    International Nuclear Information System (INIS)

    Bergqvist, L.

    1987-01-01

    Different techniques for the characterization of radioactive colloids, used in nuclear medicine, have been evaluated and compared. Several radioactive colloids have been characterized in vitro and in vivo and tested experimentally. Colloid biokinetics following interstitial or intravenous injection were evaluated with a scintillation camera technique. Lymphoscintigraphy with a Tc-99-labelled antimony sulphur colloid was performed in 32 patients with malignant melanoma in order to evaluate the technique. Based on the biokinetic results, absorbed doses in tissues and organs were calculated. The function of the reticuloendothelial system has been evaluated in rats after inoculation with tumour cells. Microfiltration and photon correlation spectroscopy were found to be suitable in determining activity-size and particle size distributions, respectively. Maximal lymph node uptake following subcutaneous injection was found to correspond to a colloid particle size between 10 and 50 nm. Lymphoscintigraphy was found to be useful in the study of lymphatic drainage from the primary tumour site in patients with malignant melanoma on the trunk. Quantitative analysis of ilio-inguinal lymph node uptake in patients with malignant melanoma on the lower extremities was, however, found to be of no value for the detection of metastatic disease in lymph nodes. High absorbed doses may be received in lymph nodes (up to 1 mGy/MBq) and at the injection site (about 10 mGy/MBq). In an experimental study it was found that the relative colloid uptake in bone marrow and spleen depended on the total number of intravenously injected particles. This may considerably affect the absorbed dose in these organs. (author)

  13. {sup 18}F-FDG uptake by spleen helps rapidly predict the dose level after total body irradiation in a Tibetan minipig model

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu Jue; Gu, Wei Wang [Southern Medical University, Department of Laboratory Animal Center, Guangzhou, Guangdong (China); Wu, Shao Jie; Guo, Kun Yuan; Chen, Chi [Southern Medical University, Department of Hematology, Zhujiang Hospital, Guangzhou, Guangdong (China); Xie, Qiang; Cai, Liang [Chinese People' s Armed Police Forces, Department of Oncology and PET/CT, Guangdong Provincial Corp Hospital, Guangzhou, Guangdong (China); Zou, Fei [Southern Medical University, School of Public Health and Tropical Medicine, Guangzhou, Guangdong (China)

    2012-09-15

    To investigate whether {sup 18}F- FDG uptake can be applied in dosimetry to facilitate the rapid and accurate evaluation of individual radiation doses after a nuclear accident. Forty-eight Tibetan minipigs were randomised into a control group (n = 3) and treatment groups (n = 45). {sup 18}F-FDG combined positron-emission tomography and computed tomography (PET/CT) were carried out before total body irradiation (TBI) and at 6, 24 and 72 h after receiving TBI doses ranging from 1 to 11 Gy. Spleen tissues and blood samples were also collected for histological examination, apoptosis and blood analysis. Mean standardised uptake values (SUVs) of the spleen showed significant differences between the experimental and the control groups. Spleen SUV at 6 h post-irradiation showed significant correlation with radiation dose; Spearman's correlation coefficient was 0.97 (P < 0.01). Histological observations showed that damage to the splenic lymphocyte became more severe with an increase in the radiation dose. Moreover, apoptosis was one of the major routes of splenic lymphocyte death, which was also confirmed by flow cytometry analysis. In the Tibetan minipig model, radiation doses have a close relationship with the {sup 18}F-FDG uptake of the spleen. This finding suggests that {sup 18}F-FDG PET/CT may be useful for the rapid detection of individual radiation doses. (orig.)

  14. {sup 99} {sup m}Tc-sulphur-colloid and heat-denatured {sup 99} {sup m}Tc-labelled red cell scans demonstrating a giant intrapelvic spleen in a girl after splenectomy

    Energy Technology Data Exchange (ETDEWEB)

    Kao, P.F. [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital and Chang Gung University School of Medicine, Tauyuan, Taiwan (Taiwan); Dept. of Nuclear Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan (Taiwan); Tzen, K.Y.; Tsai, M.F. [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital and Chang Gung University School of Medicine, Tauyuan, Taiwan (Taiwan); Lin, J.N. [Dept. of Paediatric Surgery, Chang Gung Childrens Hospital and Chang Gung University School of Medicine, Tauyuan, Taiwan (Taiwan)

    2001-04-01

    A 17 x 12 x 5-cm giant intrapelvic mass in a 14-year-old girl is reported. This mass developed 6 years after a splenectomy for splenic torsion. The heat-denatured {sup 99} {sup m}Tc-labelled red cell scan and {sup 99} {sup m}Tc- sulphur-colloid scan confirmed the specific red cell sequestration function and reticuloendothelial activity in the giant intrapelvic spleen. The size and development of the giant intrapelvic spleen are unusual. The usefulness of functional images to diagnosis the nature of the intrapelvic mass is well demonstrated. (orig.)

  15. A study of technetium-labelled sulphide colloid uptake by regional lymph nodes draining a tumour-bearing area

    International Nuclear Information System (INIS)

    Boak, J.L.; Agwunobi, T.C.

    1978-01-01

    With appropriate controls, experimental groups of inbred C 3 H mice bearing a syngeneic mammary carcinoma challenge in their right rear footpads were injected in both rear footpads with 99 Tcsup(m)ASC. Mice were sacrificed 15 and 90 min after the labelled colloid injection. Popliteal and sacral lymph nodes were weighed and counted in a well scintillation counter. A marked inhibition of labelled colloid uptake was demonstrated in regional lymph nodes draining a tumour-bearing area. Rabbits bearing VX 2 carcinoma in a forelimb received 99 Tc sup(m)ASC into each front footpad. Depression of labelled colloid uptake by regional lymph nodes draining tumour was evident on gamma-camera scanning. (author)

  16. Increased Plasma Colloid Osmotic Pressure Facilitates the Uptake of Therapeutic Macromolecules in a Xenograft Tumor Model

    Directory of Open Access Journals (Sweden)

    Matthias Hofmann

    2009-08-01

    Full Text Available Elevated tumor interstitial fluid pressure (TIFP is a characteristic of most solid tumors. Clinically, TIFP may hamper the uptake of chemotherapeutic drugs into the tumor tissue reducing their therapeutic efficacy. In this study, a means of modulating TIFP to increase the flux of macromolecules into tumor tissue is presented, which is based on the rationale that elevated plasma colloid osmotic pressure (COP pulls water from tumor interstitium lowering the TIFP. Concentrated human serum albumin: (20% HSA, used as an agent to enhance COP, reduced the TIFP time-dependently from 8 to 2 mm Hg in human tumor xenograft models bearing A431 epidermoid vulva carcinomas. To evaluate whether this reduction facilitates the uptake of macromolecules, the intratumoral distribution of fluorescently conjugated dextrans (2.5 mg/ml and cetuximab (2.0 mg/ml was probed using novel time domain nearinfrared fluorescence imaging. This method permitted discrimination and semiquantification of tumor-accumulated conjugate from background and unspecific probe fluorescence. The coadministration of 20% HSA together with either dextrans or cetuximab was found to lower the TIFP significantly and increase the concentration of the substances within the tumor tissue in comparison to control tumors. Furthermore, combined administration of 20%HSA plus cetuximab reduced the tumor growth significantly in comparison to standard cetuximab treatment. These data demonstrate that increased COP lowers the TIFP within hours and increases the uptake of therapeutic macromolecules into the tumor interstitium leading to reduced tumor growth. This model represents a novel approach to facilitate the delivery of therapeutics into tumor tissue, particularly monoclonal antibodies.

  17. Liver and spleen scintigraphy

    International Nuclear Information System (INIS)

    Devries, D.F.

    1988-01-01

    Since the introduction of liver and spleen scintigraphy in the early 1950s, it has undergone considerable changes, the most notable being technetium 99m sulfur colloid, the gamma camera, and single photon emission computed tomography (SPECT). What is the role f liver-spleen scintigraphy in this high-technology society? This chapter attempts to address this question by looking at the radiopharmaceuticals, the technique, and most importantly, the application of scintigraphy to the diagnosis of focal and diffuse hepatic and splenic disease

  18. Tc-99m colloid lung uptake in a rare case of toxoplasmosis with liver involvement

    International Nuclear Information System (INIS)

    Garty, I.; Tal, I.; Kaynan, A.

    1984-01-01

    Intensive lung accumulation of colloid (Tc-99m phytate) was demonstrated in a child suffering from acquired toxoplasmosis with a rare manifestation of severe liver damage. The possible mechanism and clinical importance of colloid lung concentration in this case is briefly discussed, including a review of the literature on this subject

  19. Spleen size changes in children with homozygous β-thalassaemia in relation to blood transfusion

    International Nuclear Information System (INIS)

    Karpathios, Th.; Antypas, A.; Dimitriou, P.; Nicolaidou, P.; Fretzayas, A.; Thomaidis, Th.; Matsaniotis, N.

    1982-01-01

    18 thalassaemic children, aged 3.5 to 13 years comprise our clinical material. In 14 of them, clinically elicited spleen markings, haematocrit, blood platelet count and red cell morphology were studied daily for a whole period between 2 transfusions. In 10 patients considerable changes in spleen size were noticed. According to our clinical observations the spleen size starts decreasing 1 to 3 d after blood transfusion up to the 10th posttransfusion day fluctuating thereafter to reach its maximum size again prior to the next blood transfusion. The decrease of spleen size was followed by an increase of haematocrit and blood platelet count and vice versa. 4 additional children were studied clinically only twice: prior to and 7 to 10 d after blood transfusion. A definite decrease of the spleen size following blood transfusion was observed. Spleen and liver sup(99m)Tc-sulfur colloid uptake was studied in 10 of the above children prior to and 7 to 10 d after blood transfusion. Statistically significant post-transfusion increase of the spleen uptake was demonstrated. Our findings suggest that (a) splenic size is relevant to blood volume sequestrated int this organ, (b) splenic radioactive uptake increases with its post-transfusion reductin in size. (author)

  20. Spleen removal

    Science.gov (United States)

    ... Philadelphia, PA: Elsevier; 2017:1505-1509. Poulose BK, Holzman MD. The spleen. In: Townsend CM Jr, Beauchamp ... provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial ...

  1. In whole blood, LPS, TNF-alpha and GM-CSF increase monocyte uptake of 99mtechnetium stannous colloid but do not affect neutrophil uptake

    International Nuclear Information System (INIS)

    Ramsay, Stuart C.; Maggs, Jacqueline; Powell, Kellie; Barnes, Jodie; Ketheesan, Natkunam

    2006-01-01

    Introduction: 99m Technetium stannous colloid (TcSnC) is used in white cell scanning. It labels neutrophils and monocytes via phagocytosis, with uptake mediated by the phagocytic receptor CD11b/CD18 in neutrophils. Uptake of TcSnC is altered by gram-negative infection, possibly due to the endotoxin component lipopolysaccharide (LPS) or to cytokines released during infection (e.g., TNF-alpha and IFN-gamma). Endotoxemia and increased TNF-alpha levels also occur in inflammatory bowel disease. Another potential confounder in cell labeling is that sepsis patients may be treated with GM-CSF and G-CSF, which alter phagocytic cell function. This study aimed to determine how these factors affect TcSnC cellular uptake. Methods: Whole blood from six healthy volunteers was incubated with LPS, TNF-alpha, IFN-gamma, GM-CSF or G-CSF. Samples were then mixed with TcSnC. Blood was separated across density gradients and imaged using a gamma camera. Three radioactive count peaks were observed in each tube: free plasma activity, mononuclear cell uptake and neutrophil uptake. Results: Compared with controls, significant increases in mononuclear cell uptake were induced by LPS, TNF-alpha and GM-CSF stimulation. It was incidentally noted that exogenous estrogens appear to affect TcSnC labeling and may influence the neutrophil response to stimulation. Neutrophil uptake and plasma activity were not significantly affected. IFN-gamma and G-CSF had no significant effect. Conclusions: In whole blood, the effect of LPS on TcSnC monocyte uptake is different to its effect on neutrophils, consistent with previously reported differences in CD11b/CD18 expression. TNF-alpha response parallels LPS response. GM-CSF also increases TcSnC uptake by monocytes. These effects should be considered when using TcSnC for imaging purposes, as they will tend to increase monocyte labeling. Estrogens may also affect TcSnC labeling. Responses to IFN-gamma and G-CSF are consistent with previously reported effects of

  2. In whole blood, LPS, TNF-alpha and GM-CSF increase monocyte uptake of {sup 99m}technetium stannous colloid but do not affect neutrophil uptake

    Energy Technology Data Exchange (ETDEWEB)

    Ramsay, Stuart C. [Townsville Nuclear Medicine, Mater Hospital, Pimlico, Queensland 4812 (Australia) and School of Medicine, James Cook University, Townsville, Queensland 4811 (Australia)]. E-mail: stuart.ramsay1@jcu.edu.au; Maggs, Jacqueline [Department of Nuclear Medicine, Townsville Hospital, Townsville, Queensland 4814 (Australia); Powell, Kellie [School of Veterinary and Biomedical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); School of Medicine, James Cook University, Townsville, Queensland 4811 (Australia); Barnes, Jodie [School of Veterinary and Biomedical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); Ketheesan, Natkunam [School of Veterinary and Biomedical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); School of Medicine, James Cook University, Townsville, Queensland 4811 (Australia)

    2006-07-15

    Introduction: {sup 99m}Technetium stannous colloid (TcSnC) is used in white cell scanning. It labels neutrophils and monocytes via phagocytosis, with uptake mediated by the phagocytic receptor CD11b/CD18 in neutrophils. Uptake of TcSnC is altered by gram-negative infection, possibly due to the endotoxin component lipopolysaccharide (LPS) or to cytokines released during infection (e.g., TNF-alpha and IFN-gamma). Endotoxemia and increased TNF-alpha levels also occur in inflammatory bowel disease. Another potential confounder in cell labeling is that sepsis patients may be treated with GM-CSF and G-CSF, which alter phagocytic cell function. This study aimed to determine how these factors affect TcSnC cellular uptake. Methods: Whole blood from six healthy volunteers was incubated with LPS, TNF-alpha, IFN-gamma, GM-CSF or G-CSF. Samples were then mixed with TcSnC. Blood was separated across density gradients and imaged using a gamma camera. Three radioactive count peaks were observed in each tube: free plasma activity, mononuclear cell uptake and neutrophil uptake. Results: Compared with controls, significant increases in mononuclear cell uptake were induced by LPS, TNF-alpha and GM-CSF stimulation. It was incidentally noted that exogenous estrogens appear to affect TcSnC labeling and may influence the neutrophil response to stimulation. Neutrophil uptake and plasma activity were not significantly affected. IFN-gamma and G-CSF had no significant effect. Conclusions: In whole blood, the effect of LPS on TcSnC monocyte uptake is different to its effect on neutrophils, consistent with previously reported differences in CD11b/CD18 expression. TNF-alpha response parallels LPS response. GM-CSF also increases TcSnC uptake by monocytes. These effects should be considered when using TcSnC for imaging purposes, as they will tend to increase monocyte labeling. Estrogens may also affect TcSnC labeling. Responses to IFN-gamma and G-CSF are consistent with previously reported effects

  3. Scintigraphy of liver and spleen in vinyl chloride workers

    International Nuclear Information System (INIS)

    Biersack, H.J.; San Luis, T. Jr.; Lange, C.E.; Thelen, M.; Veltman, G.; Winkler, C.; Bonn Univ.; Bonn Univ.

    1977-01-01

    In 152 VC-exposed workers of whom 124 were employed in the PVC-production and 28 in VC-processing plants liver and spleen imaging was performed using sup(99m)Tc-sulphur colloid and 197 Hg-BMHP. In 101 (= 81%) of the 124 workers of the PVC-production plant and in 18 (= 64%) workers of PVC-processing factories pathological liver and spleen scintigrams were found. The most frequent pathological change in the scintigraphic image was an increase in splenic colloid accumulation, when compared with the liver uptake. Three angiosarcomas of the liver were detected through circumscribed defects of colloid accumulation. Sequential liver scintigraphy was done in 15 cases. In 7 patients with esophageal varices considerable decrease in portal venous blood flow was demonstrated. - As a result of our investigations it can be stated that scintigraphically detectable changes are sensitive indicators of VC-induced lesions of the liver including liver fibrosis, portal hypertension and angiosarcoma. (orig.) [de

  4. The function of the spleen in adults after ligation of the splenic artery of the traumatized spleen in childhood.

    Science.gov (United States)

    Keramidas, Dimitrios C; Soutis, Michael

    2003-05-01

    Ligation of the splenic artery (LSA) has been successfully used as a spleen-saving procedure in rare cases of splenic trauma in children in which management with splenorrhaphy or partial splenectomy alone was not possible. There are no data regarding the long-term effects of the procedure on the functional status of the spleen. The purpose of this study is to present and discuss our clinical and laboratory findings in adults who underwent LSA in childhood. Our first 2 patients in whom LSA was done at ages 4 and 2 years in 1977 underwent the following examinations in the year 2000: 1, imaging of the spleen; 2, immunologic studies; and 3, peripheral blood tests. Their ages at reexamination were 27 and 25 years, respectively. Results were as follows: triplex ultrasound revealed normal size and echomorphology; Doppler techniques revealed normal vasculature; 99mTc-Tin colloid scanning revealed normal uptake. Immunoglobulins (IgG1 to IgG4, IgA, IgM, IgE), complement fraction (C3, C4), antibodies response to vaccinations, and peripheral blood tests all had normal results. No Howell-Jolly bodies were found. Laboratory investigations in adults with LSA during childhood disclosed undisturbed function of the spleen. LSA can be used as an adjunct to splenorrhaphy in children with rare splenic injuries involving major hilar vessels.

  5. Splenic uptake of both technetium-99m diphosphonate and technetium-99m sulfur colloid in sickle cell beta degrees thalassemia

    International Nuclear Information System (INIS)

    Heck, L.L.; Brittin, G.M.

    1989-01-01

    A 19-year-old black woman with sickle cell beta degrees thalassemia had experienced more than 100 hospital admissions for sickle cell crisis and aseptic necrosis of both femoral heads. Her spleen was enlarged threefold and accumulated both radiocolloid and bone-seeking agent on two occasions, demonstrating an exception to the rule in sickle cell anemia that spleens that take up bone-seeking agents demonstrate functional asplenia. In the context of fever, left upper quadrant pain, and splenomegaly, the pattern of calcification in the patient's spleen as revealed in ultrasound and CT studies suggested possible abscess and led to unnecessary splenectomy. The nuclear medicine studies did not support this diagnosis. Nuclear medicine physicians should not be misled by splenic findings of sickle cell thalassemia (and possibly of other heterozygous sickle cell disorders) that differ from those of the more familiar homozygous sickle cell anemia

  6. Concentrations of metals in water, sediment, biofilm, benthic macroinvertebrates, and fish in the Boulder River watershed, Montana, and the role of colloids in metal uptake

    Science.gov (United States)

    Farag, A.M.; Nimick, D.A.; Kimball, B.A.; Church, S.E.; Harper, D.D.; Brumbaugh, W.G.

    2007-01-01

    To characterize the partitioning of metals in a stream ecosystem, concentrations of trace metals including As, Cd, Cu, Pb, and Zn were measured in water, colloids, sediment, biofilm (also referred to as aufwuchs), macroinvertebrates, and fish collected from the Boulder River watershed, Montana. Median concentrations of Cd, Cu, and Zn in water throughout the watershed exceeded the U.S. EPA acute and chronic criteria for protection of aquatic life. Concentrations of As, Cd, Cu, Pb, and Zn in sediment were sufficient in the tributaries to cause invertebrate toxicity. The concentrations of As, Cu, Cd, Pb, and Zn in invertebrates from lower Cataract Creek (63, 339, 59, 34, and 2,410 μg/g dry wt, respectively) were greater than the concentrations in invertebrates from the Clark Fork River watershed, Montana (19, 174, 2.3, 15, and 648 μg/g, respectively), that were associated with reduced survival, growth, and health of cutthroat trout fed diets composed of those invertebrates. Colloids and biofilm seem to play a critical role in the pathway of metals into the food chain and concentrations of As, Cu, Pb, and Zn in these two components are significantly correlated. We suggest that transfer of metals associated with Fe colloids to biological components of biofilm is an important pathway where metals associated with abiotic components are first available to biotic components. The significant correlations suggest that Cd, Cu, and Zn may move independently to biota (biofilm, invertebrates, or fish tissues) from water and sediment. The possibility exists that Cd, Cu, and Zn concentrations increase in fish tissues as a result of direct contact with water and sediment and indirect exposure through the food chain. However, uptake through the food chain to fish may be more important for As. Although As concentrations in colloids and biofilm were significantly correlated with As water concentrations, As concentrations in fish tissues were not correlated with water. The pathway

  7. Effect of surface charge on the colloidal stability and in vitro uptake of carboxymethyl dextran-coated iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Ayala, Vanessa; Herrera, Adriana P.; Latorre-Esteves, Magda; Torres-Lugo, Madeline [University of Puerto Rico, Department of Chemical Engineering (United States); Rinaldi, Carlos, E-mail: carlos.rinaldi@bme.ufl.edu [University of Florida, J. Crayton Pruitt Family Department of Biomedical Engineering (United States)

    2013-08-15

    Nanoparticle physicochemical properties such as surface charge are considered to play an important role in cellular uptake and particle-cell interactions. In order to systematically evaluate the role of surface charge on the uptake of iron oxide nanoparticles, we prepared carboxymethyl-substituted dextrans with different degrees of substitution, ranging from 38 to 5 groups per chain, and reacted them using carbodiimide chemistry with amine-silane-coated iron oxide nanoparticles with narrow size distributions in the range of 33-45 nm. Surface charge of carboxymethyl-substituted dextran-coated nanoparticles ranged from -50 to 5 mV as determined by zeta potential measurements, and was dependent on the number of carboxymethyl groups incorporated in the dextran chains. Nanoparticles were incubated with CaCo-2 human colon cancer cells. Nanoparticle-cell interactions were observed by confocal laser scanning microscopy and uptake was quantified by elemental analysis using inductively coupled plasma mass spectroscopy. Mechanisms of internalization were inferred using pharmacological inhibitors for fluid-phase, clathrin-mediated, and caveola-mediated endocytosis. Results showed increased uptake for nanoparticles with greater negative charge. Internalization patterns suggest that uptake of the most negatively charged particles occurs via non-specific interactions.

  8. MORPHOMETRY OF SPLEEN

    Directory of Open Access Journals (Sweden)

    Radhika

    2016-03-01

    Full Text Available INTRODUCTION Spleen is organ of lymphatic system located on left side of abdominal cavity under diaphragm. It is a secondary lymphatic organ that plays an important role in cell mediated immunity. Foetal spleen is erythropoietic in nature. MATERIAL & METHODS Present study was done in 50 adult spleens and 50 foetal spleens. RESULTS Morphometric features like length, breadth, thickness & weight are measured. Length varied from 6.3 to 12.5 cm, breadth varied from 2.6 to 8.6 cm, thickness ranged from 2 cm to 4.6 cm, weight ranged from 65 g to 225 g. Average total length of spleen is 2.52 cm x 1.76 x 2 cm, weight 6.5 g. Shapes of spleens observed wedge shape spleen–48%, tetrahedral spleen–24%, triangular spleen-28%. Splenic notches on superior border & inferior border are observed. Incident of accessory spleen in 1% of cases. CONCLUSIONS Present knowledge of study may be helpful for surgeons in surgical procedures like splenectomy, resection of tumours and extirpation of cysts

  9. Lysine-functionalized nanodiamonds as gene carriers: development of stable colloidal dispersion for in vitro cellular uptake studies and siRNA delivery application.

    Science.gov (United States)

    Alwani, Saniya; Kaur, Randeep; Michel, Deborah; Chitanda, Jackson M; Verrall, Ronald E; Karunakaran, Chithra; Badea, Ildiko

    2016-01-01

    Nanodiamonds (NDs) are emerging as an attractive tool for gene therapeutics. To reach their full potential for biological application, NDs should maintain their colloidal stability in biological milieu. This study describes the behavior of lysine-functionalized ND (lys-ND) in various dispersion media, with an aim to limit aggregation and improve the colloidal stability of ND-gene complexes called diamoplexes. Furthermore, cellular and macromolecular interactions of lys-NDs are also analyzed in vitro to establish the understanding of ND-mediated gene transfer in cells. lys-NDs were synthesized earlier through covalent conjugation of lysine amino acid to carboxylated NDs surface generated through re-oxidation in strong oxidizing acids. In this study, dispersions of lys-NDs were prepared in various media, and the degree of sedimentation was monitored for 72 hours. Particle size distributions and zeta potential measurements were performed for a period of 25 days to characterize the physicochemical stability of lys-NDs in the medium. The interaction profile of lys-NDs with fetal bovine serum showed formation of a protein corona, which was evaluated by size and charge distribution measurements. Uptake of lys-NDs in cervical cancer cells was analyzed by scanning transmission X-ray microscopy, flow cytometry, and confocal microscopy. Cellular uptake of diamoplexes (complex of lys-NDs with small interfering RNA) was also analyzed using flow cytometry. Aqueous dispersion of lys-NDs showed minimum sedimentation and remained stable over a period of 25 days. Size distributions showed good stability, remaining under 100 nm throughout the testing period. A positive zeta potential of >+20 mV indicated a preservation of surface charges. Size distribution and zeta potential changed for lys-NDs after incubation with blood serum, suggesting an interaction with biomolecules, mainly proteins, and a possible formation of a protein corona. Cellular internalization of lys-NDs was confirmed

  10. Lysine-functionalized nanodiamonds as gene carriers: development of stable colloidal dispersion for in vitro cellular uptake studies and siRNA delivery application

    Directory of Open Access Journals (Sweden)

    Alwani S

    2016-02-01

    Full Text Available Saniya Alwani,1 Randeep Kaur,1 Deborah Michel,1 Jackson M Chitanda,2 Ronald E Verrall,3 Chithra Karunakaran,4 Ildiko Badea1 1Drug Design and Discovery Research Group, College of Pharmacy and Nutrition, 2Department of Chemical & Biological Engineering, 3Department of Chemistry, University of Saskatchewan, 4Canadian Light Source, Saskatoon, SK, Canada Purpose: Nanodiamonds (NDs are emerging as an attractive tool for gene therapeutics. To reach their full potential for biological application, NDs should maintain their colloidal stability in biological milieu. This study describes the behavior of lysine-functionalized ND (lys-ND in various dispersion media, with an aim to limit aggregation and improve the colloidal stability of ND-gene complexes called diamoplexes. Furthermore, cellular and macromolecular interactions of lys-NDs are also analyzed in vitro to establish the understanding of ND-mediated gene transfer in cells. Methods: lys-NDs were synthesized earlier through covalent conjugation of lysine amino acid to carboxylated NDs surface generated through re-oxidation in strong oxidizing acids. In this study, dispersions of lys-NDs were prepared in various media, and the degree of sedimentation was monitored for 72 hours. Particle size distributions and zeta potential measurements were performed for a period of 25 days to characterize the physicochemical stability of lys-NDs in the medium. The interaction profile of lys-NDs with fetal bovine serum showed formation of a protein corona, which was evaluated by size and charge distribution measurements. Uptake of lys-NDs in cervical cancer cells was analyzed by scanning transmission X-ray microscopy, flow cytometry, and confocal microscopy. Cellular uptake of diamoplexes (complex of lys-NDs with small interfering RNA was also analyzed using flow cytometry. Results: Aqueous dispersion of lys-NDs showed minimum sedimentation and remained stable over a period of 25 days. Size distributions showed

  11. Laparoscopic Spleen Removal (Splenectomy)

    Science.gov (United States)

    ... Affairs and Humanitarian Efforts Login Laparoscopic Spleen Removal (Splenectomy) Patient Information from SAGES Download PDF Find a ... are suspected. What are the Advantages of Laparoscopic Splenectomy? Individual results may vary depending on your overall ...

  12. Detection of accessory spleens with indium 111-labeled autologous platelets

    International Nuclear Information System (INIS)

    Davis, H.H. II; Varki, A.; Heaton, W.A.; Siegel, B.A.

    1980-01-01

    In two patients with recurrent immune thrombocytopenia, accessory splenic tissue was demonstrated by radionuclide imaging following administration of indium 111-labeled autologous platelets. In one of these patients, no accessory splenic tissue was seen on images obtained with technetium 99m sulfur colloid. This new technique provides a simple means for demonstrating accessory spleens and simultaneously evaluating the life-span of autologous platelets

  13. Candidiasis of the liver and spleen in childhood

    International Nuclear Information System (INIS)

    Miller, J.H.; Greenfield, L.D.; Wald, B.R.

    1982-01-01

    Four children with acute leukemia and surgically documented candidiasis of the liver and/or spleen were examined with a combination of diagnostic imaging modalities including /sup 99m/Tc-sulfur colloid and /sup 67/Ga- citrate scintigraphy, gray-scale ultrasound, and body computed tomography (CT). Abnormalities were detected in every individual examined. /sup 99m/Tc-sulfur colloid scintigraphy revealed ''cold'' areas in the liver or spleen. With /sup 67/Ga scintigraphy, these areas were ''cold'' in some individuals and ''hot'' in others. Gray-scale ultrasound demonstrated hypoechoic lesions with central areas of increased echogenicity in hepatic involvement, and hypoechoic replacement of the spleen in splenic involvement. CT in one patient revealed low-density areas without contrast enhancement within the hepatic parenchyma and unsuspected renal involvement

  14. Candidiasis of the liver and spleen in childhood

    International Nuclear Information System (INIS)

    Miller, J.H.; Greenfield, L.D.; Wald, B.R.

    1982-01-01

    Four children with acute leukemia and surgically documented candidiasis of the liver and/or spleen were examined with a combination of diagnostic imaging modalities including 99 mTc-sulfur colloid and 67 Ga-citrate scintigraphy, gray-scale ultrasound, and body computed tomography (CT). Abnormalities were detected in every individual examined. 99 mTc-sulfur colloid scintigraphy revealed cold areas in the liver or spleen. With 67 Ga scintigraphy, these areas were cold in some individuals and hot in others. Gray-scale ultrasound demonstrated hypoechoic lesions with central areas of increased echogenicity in hepatic involvement, and hypoechoic replacement of the spleen in splenic involvement. CT in one patient revealed low-density areas without contrast enhancement within the hepatic parenchyma and unsuspected renal involvement

  15. Candidiasis of the liver and spleen in childhood

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.H. (Childrens Hospital of Los Angeles, CA); Greenfield, L.D.; Wald, B.R.

    1982-02-01

    Four children with acute leukemia and surgically documented candidiasis of the liver and/or spleen were examined with a combination of diagnostic imaging modalities including /sup 99m/Tc-sulfur colloid and /sup 67/Ga- citrate scintigraphy, gray-scale ultrasound, and body computed tomography (CT). Abnormalities were detected in every individual examined. /sup 99m/Tc-sulfur colloid scintigraphy revealed ''cold'' areas in the liver or spleen. With /sup 67/Ga scintigraphy, these areas were ''cold'' in some individuals and ''hot'' in others. Gray-scale ultrasound demonstrated hypoechoic lesions with central areas of increased echogenicity in hepatic involvement, and hypoechoic replacement of the spleen in splenic involvement. CT in one patient revealed low-density areas without contrast enhancement within the hepatic parenchyma and unsuspected renal involvement.

  16. Candidiasis of the liver and spleen in childhood

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.H.; Greenfield, L.D.; Wald, B.R.

    1982-02-01

    Four children with acute leukemia and surgically documented candidiasis of the liver and/or spleen were examined with a combination of diagnostic imaging modalities including /sup 99/mTc-sulfur colloid and /sup 67/Ga-citrate scintigraphy, gray-scale ultrasound, and body computed tomography (CT). Abnormalities were detected in every individual examined. /sup 99/mTc-sulfur colloid scintigraphy revealed cold areas in the liver or spleen. With /sup 67/Ga scintigraphy, these areas were cold in some individuals and hot in others. Gray-scale ultrasound demonstrated hypoechoic lesions with central areas of increased echogenicity in hepatic involvement, and hypoechoic replacement of the spleen in splenic involvement. CT in one patient revealed low-density areas without contrast enhancement within the hepatic parenchyma and unsuspected renal involvement.

  17. Colloidal organization

    CERN Document Server

    Okubo, Tsuneo

    2015-01-01

    Colloidal Organization presents a chemical and physical study on colloidal organization phenomena including equilibrium systems such as colloidal crystallization, drying patterns as an example of a dissipative system and similar sized aggregation. This book outlines the fundamental science behind colloid and surface chemistry and the findings from the author's own laboratory. The text goes on to discuss in-depth colloidal crystallization, gel crystallization, drying dissipative structures of solutions, suspensions and gels, and similar-sized aggregates from nanosized particles. Special emphas

  18. Histochemical evidence for the differential surface labeling, uptake, and intracellular transport of a colloidal gold-labeled insulin complex by normal human blood cells

    International Nuclear Information System (INIS)

    Ackerman, G.A.; Wolken, K.W.

    1981-01-01

    A colloidal gold-labeled insulin-bovine serum albumin (GIA) reagent has been developed for the ultrastructural visualization of insulin binding sites on the cell surface and for tracing the pathway of intracellular insulin translocation. When applied to normal human blood cells, it was demonstrated by both visual inspection and quantitative analysis that the extent of surface labeling, as well as the rate and degree of internalization of the insulin complex, was directly related to cell type. Further, the pathway of insulin (GIA) transport via round vesicles and by tubulo-vesicles and saccules and its subsequent fate in the hemic cells was also related to cell variety. Monocytes followed by neutrophils bound the greatest amount of labeled insulin. The majority of lymphocytes bound and internalized little GIA, however, between 5-10% of the lymphocytes were found to bind considerable quantities of GIA. Erythrocytes rarely bound the labeled insulin complex, while platelets were noted to sequester large quantities of the GIA within their extracellular canalicular system. GIA uptake by the various types of leukocytic cells appeared to occur primarily by micropinocytosis and by the direct opening of cytoplasmic tubulo-vesicles and saccules onto the cell surface in regions directly underlying surface-bound GIA. Control procedures, viz., competitive inhibition of GIA labeling using an excess of unlabeled insulin in the incubation medium, preincubation of the GIA reagent with an antibody directed toward porcine insulin, and the incorporation of 125I-insulin into the GIA reagent, indicated the specificity and selectivity of the GIA histochemical procedure for the localization of insulin binding sites

  19. 90Y-labeled antimony trisulfide colloid as promising therapeutic agent: Physicochemical characterization and biological evaluation

    Directory of Open Access Journals (Sweden)

    Janković Drina Lj.

    2014-01-01

    Full Text Available Introduction The suitability of 90Y-labeled antimony trisulfide colloid (ATC for the preparation of therapeutic radiopharmaceutical was studied taking into accounts its physicochemical properties and biological behavior in rats. Material and methods The labeling efficiency of 90Y- and 99mTc-labeled colloid particles was investigated by ITLC-SG and paper chromatography, the in vitro stability of the colloid was tested in human serum, while in vivo experiments were performed on healthy Wistar rats. Analysis of the particles enclosed the size (TEM, determination of the zeta potential (Zetasizer Nano as well as radioactivity particle size distribution (filtration analysis. Results 90Y-labeled ATC can be prepared in high yield under investigated conditions Labeling efficiency was >95% and filtration analysis showed that more than 90% of radioactive particles were smaller than 20 nm. The particles with the size range of 6-22 nm were achieved by using polyvinyipyrrolidone (mol wt ~44,000. The 90Y-ATC was quite stable in vitro in human serum. Tissue distribution studies in rats confirmed that the liver and spleen uptake of 90Y-labeled colloid was three-fold lower in comparison with 99mTc-ATC, although the bone uptake was five-fold higher at 20 min post injection. Conclusions 90Y-labeled ATC showed high labeling efficiency and good stability, and might be well suited for therapeutic application in nuclear medicine.

  20. Spleen removal - open - adults - discharge

    Science.gov (United States)

    ... discharge; Spleen removal - adult - discharge References Poulose BK, Holzman MD. The spleen. In: Townsend CM, Beauchamp RD, ... provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial ...

  1. Paediatric Wandering Spleens in Malawi

    African Journals Online (AJOL)

    by a double layer of peritoneum. The wandering spleen is the rare description of an abnormally positioned spleen, which is thought to occur due to laxity, abnormality or absence of the aforementioned ligaments. The wandering spleen is noted to have a longer than normal pedicle, and because of its intraperitoneal location, ...

  2. Colloidal glasses

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Colloidal glasses. Glassy state is attained when system fails to reach equilibrium due to crowding of constituent particles. In molecular glasses, glassy state is reached by rapidly lowering the temperature. In colloidal glasses, glassy state is reached by increasing the ...

  3. Use of liver-spleen scintigraphy to detect immune status and Kaposi sarcoma in AIDS patients

    International Nuclear Information System (INIS)

    Ganz, W.I.; Heiba, S.; Ganz, S.S.; Serafini, A.N.

    1987-01-01

    Fifty-one patients seropositive for human immunodeficiency virus (HIV) underwent liver-spleen scintigraphy. In 43 clinically immunocompromised patients splenic activity was decreased or absent. Eight of these patients had enlarged spleens with decreased uptake. Autopsy results are available on three, all of whom had Kaposi sarcoma of the spleen. Splenic uptake was initially demonstrated in six HTV-positive patients. In three of these subsequently symptomatic patients, follow-up scans showed decreased splenic uptake. Two non-AIDS, HIV-positive patients had normal splenic uptake. These preliminary data suggest that AIDS patients initially have increased uptake, which progresses to decreased splenic uptake as the patients become immunocompromised. Azidothymidine reversed this pattern in one patient. In addition, splenic enlargement with decreased uptake suggests the presence of Kaposi sarcoma

  4. Isolated Amoebic Abscess of Spleen

    Directory of Open Access Journals (Sweden)

    Kaushik M

    2013-04-01

    Full Text Available Amoebic liver abscess is the most common extraintestinal manifestation of amoebiasis. Extrahepatic amoebic abscesses have occasionally been described in the lung, brain, and skin and presumably result from hematogenous spread. Isolated amoebic abscess of spleen has been reported scarcely in literature. We report here a case of isolated amoebic abscess of spleen.

  5. Colloidal nematostatics

    Directory of Open Access Journals (Sweden)

    V.M. Pergamenshchik

    2010-01-01

    Full Text Available We give a review of the theory of large distance colloidal interaction via the nematic director field. The new area of nematic colloidal systems (or nematic emulsions has been guided by the analogy between the colloidal nematostatics and electrostatics. The elastic charge density representation of the colloidal nematostatics [V.M. Pergamenshchik, V.O. Uzunova, Eur. Phys. J. E, 2007, 23, 161; Phys. Rev. E, 2007, 76, 011707] develops this analogy at the level of charge density and Coulomb interaction. The analogy is shown to lie in common mathematics based on the solutions of Laplace equation. However, the 3d colloidal nematostatics substantially differs from electrostatics both in its mathematical structure and physical implications. The elastic charge is a vector fully determined by the torque exerted upon colloid, the role of Gauss' theorem is played by conservation of the torque components. Elastic multipoles consist of two tensors (dyads. Formulas for the elastic multipoles, the Coulomb-like, dipole-dipole, and quadrupole-quadrupole pair interaction potentials are derived and illustrated by particular examples. Based on the tensorial structure, we list possible types of elastic dipoles and quadrupoles. An elastic dipole is characterized by its isotropic strength, anisotropy, chirality, and its longitudinal component. An elastic quadrupole can be uniaxial and biaxial. Relation between the multipole type and its symmetry is discussed, sketches of some types of multipoles are given. Using the mirror image method of electrostatics as a guiding idea, we develop the mirror image method in nematostatics for arbitrary director tilt at the wall. The method is applied to the charge-wall and dipole-wall interaction.

  6. Colloidal superballs

    NARCIS (Netherlands)

    Rossi, L.

    2012-01-01

    This thesis is organized in four parts as follows. Part 1 focuses on the synthetic aspects of the colloidal model systems that will be used throughout the work described in this thesis. In Chapter 2 we describe synthetic procedures for the preparation of polycrystalline hematite superballs and

  7. Colloidal polyaniline

    Science.gov (United States)

    Armes, Steven P.; Aldissi, Mahmoud

    1990-01-01

    Processable electrically conductive latex polymer compositions including colloidal particles of an oxidized, polymerized amino-substituted aromatic monomer, a stabilizing effective amount of a random copolymer containing amino-benzene type moieties as side chain constituents, and dopant anions, and a method of preparing such polymer compositions are provided.

  8. Value of selective spleen scintigraphy when liver/spleen image shows equivocal spleen defects: concise communication

    International Nuclear Information System (INIS)

    Van Nostrand, D.; Corley, J.H.; Kyle, R.W.; Stotler, R.E.

    1983-01-01

    A retrospective review was performed to determine the utility of selective spleen scintigraphy (SSS) in the evaluation of equivocal defects on liver/splen (LS) image. Six of seven questionable features on LS image were classified on SSS to be definite defects in three, and normal in three. Three of seven patients had defects on SSS that were not seen on LS image. The inability of the LS image to exclude or delineate an abnormality in the spleen was attributed to an overlying left lobe of the liver in five, and to technique in one. The SSS is a valuable diagnostic tool in the further evaluation of equivocal spleen defects on LS image, and SSS may demonstrate abnormalities not demonstrated on LS image

  9. Torsion of a wandering spleen

    African Journals Online (AJOL)

    No improvement was noted on detorsion of the vascular pedicle, and a splenectomy was performed. The spleen measured 120×90×55 mm and weighed 250 g. Histological examination of the organ identified significant haemorrhagic congestion associated with diffuse haemorrhagic necrosis, with no neoplasm or infiltrate.

  10. The forgotten organ: Contrast enhanced sonography of the spleen

    Energy Technology Data Exchange (ETDEWEB)

    Goerg, Christian [Medizinische Universitaetsklinik, Baldingerstrasse, 35043 Marburg/Lahn (Germany)], E-mail: goergc@med.uni-marburg.de

    2007-11-15

    Objective: Ultrasound contrast agents in conjunction with contrast specific imaging techniques, are increasingly accepted in clinical use for diagnostic imaging in several organs. Contrast enhanced sonography (CES) of second-generation contrast media have shown a spleen-specific uptake of the microbubble contrast agent. The aim of this review is to illustrate indications for the use of CES in patients with suspected (peri-)splenic pathology. Methods: This review based on the experience of transcutaneous CES in 200 patients with (peri-)splenic pathology diagnosed by B-mode sonography at an internal medicine center. CES studies were performed with a contrast-devoted unit (Acuson, Sequoia, Siemens medical solution) that had contrast-specific, continuous-mode software. A low mechanical index was used. A sulfur hexafluoride-based microbubble contrast medium (Sonovue, Bracco SpA, Milan, Italy) was injected. Results: On our experience, there are several clinical conditions which may show an diagnostic advantage of CES in comparison to B-mode US. CES should be performed to investigate: (1) the perisplenic tumor to diagnose or exclude accessory spleen, (2) the small-sized spleen to diagnose functional asplenia/hyposplenia, (3) the inhomogenous spleen of unknown cause to diagnose focal lesions within the spleen, (4) the incidentally found hypoechoic splenic tumor to diagnose high vascular splenic hemangioma, (5) focal lesions suspect for splenic abscess, hematoma, infarction to confirme diagnosis, and (6) patients with abdominal trauma to diagnose or exclude splenic injuriy. Conclusion: CES is of diagnostic value in several clinical circumstances to diagnose accessory spleen, functional asplenia, small-sized splenic involvement, high vascular splenic hemangioma, and vascular splenic pathology like splenic infarction, splenic abscess, and splenic laceration.

  11. [Ultrasound of spleen and retroperitoneum].

    Science.gov (United States)

    Salcedo Joven, I; Segura-Grau, A; Díaz Rodríguez, N; Segura-Cabral, J M

    2016-09-01

    Ultrasound provides data of extremely great value when studying spleen pathology, being diagnostic in splenomegaly and splenic trauma, as well as offering a good approach to the diagnosis of both benign and malignant focal pathology, particularly lymphoma. However, for the evaluation of adrenal and retroperitoneal diseases, other techniques such as CT or MRI are more suitable, even though ultrasound is still an excellent screening and monitoring method, as well as being useful in non-invasive therapeutic approaches. Copyright © 2014 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Anisotropic Model Colloids

    NARCIS (Netherlands)

    van Kats, C.M.

    2008-01-01

    The driving forces for fundamental research in colloid science are the ability to manage the material properties of colloids and to unravel the forces that play a role between colloids to be able to control and understand the processes where colloids play an important role. Therefore we are

  13. A case report with atypical liver-spleen scan after splenectomy

    International Nuclear Information System (INIS)

    Gokcora, N.; Ilgin, N.; Basaklar, C.

    1992-01-01

    Remodeling of the liver following splenectomy may simulate hypertrophy of an accessory spleen on sulphur colloid scans. There are but a few reports about the persistent splenic activity as a prominent finding during the post-splenectomy period. Splenic simulation may be attributed to the unusual hepatic lobe displacement, as in this case. The clinician should be aware of possible splenic simulation in the post-splenectomy period, if hypersplenism is suspected

  14. EDITORIAL: Colloidal suspensions Colloidal suspensions

    Science.gov (United States)

    Petukhov, Andrei; Kegel, Willem; van Duijneveldt, Jeroen

    2011-05-01

    Special issue in honour of Henk Lekkerkerker's 65th birthday Professor Henk N W Lekkerkerker is a world-leading authority in the field of experimental and theoretical soft condensed matter. On the occasion of his 65th birthday in the summer of 2011, this special issue celebrates his many contributions to science. Henk Lekkerkerker obtained his undergraduate degree in chemistry at the University of Utrecht (1968) and moved to Calgary where he received his PhD in 1971. He moved to Brussels as a NATO fellow at the Université Libre de Bruxelles and was appointed to an assistant professorship (1974), an associate professorship (1977) and a full professorship (1980) in physical chemistry at the Vrije Universiteit Brussel. In 1985 he returned to The Netherlands to take up a professorship at the Van 't Hoff Laboratory, where he has been ever since. He has received a series of awards during his career, including the Onsager Medal (1999) of the University of Trondheim, the Bakhuys Roozeboom Gold Medal (2003) of the Royal Dutch Academy of Arts and Sciences (KNAW), the ECIS-Rhodia European Colloid and Interface Prize (2003), and the Liquid Matter Prize of the European Physical Society (2008). He was elected a member of KNAW in 1996, was awarded an Academy Chair position in 2005, and has held several visiting lectureships. Henk's work focuses on phase transitions in soft condensed matter, and he has made seminal contributions to both the theoretical and experimental aspects of this field. Here we highlight three major themes running through his work, and a few selected publications. So-called depletion interactions may lead to phase separation in colloid-polymer mixtures, and Henk realised that the partitioning of polymer needs to be taken into account to describe the phase behaviour correctly [1]. Colloidal suspensions can be used as model fluids, with the time- and length-scales involved leading to novel opportunities, notably the direct observation of capillary waves at a

  15. Radiolabeled colloid scintigraphy and assessment of clinical outcome in patients with alcoholic liver disease

    International Nuclear Information System (INIS)

    Bhatia, N.

    1990-01-01

    This paper evaluates the efficiency of radiolabeled colloid imaging in the determination of clinical outcome for patients with alcoholic liver disease (ALD). Tc-99m sulfur colloid or albumin colloid studies were evaluated for 74 patients referred to the nuclear medicine service for assessment of ALD or cirrhosis. Images were graded for splenic activity relative to liver on a scale of 1-5 (5 being normal), bone marrow activity on a scale of 0-3 (3 being normal), and spleen volume on a scale of 0-2 (2 being normal). A composite colloid shift index (CSI) was calculated by adding the three-individual category scores for each radiolabeled colloid study (1 being greatest colloid shift and 10 being least colloid shift). One-year survival was determined from hospital records for 55 of the 74 patients

  16. Nonvisualization of an enlarged spleen on Ga-67 scintigraphy but demonstrated by CT after splenic irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shih, W.J.; Domstad, P.A.; DeLand, F.H.; Maruyama, Y.

    1985-03-01

    The presence of an enlarged spleen using CT with the absence of splenic visualization in Ga-67 citrate images in a patient with chronic myelogenous leukemia and splenomegaly after splenic irradiation was observed. Since Howell-Jolly bodies had not been identified in the peripheral circulation, the finding of splenic nonvisualization was explained by disassociated splenic functions, which are not tightly coupled, and some activities that can be suppressed by irradiation without impairing others. The Ga-67 splenic localization mechanism is probably more sensitive and liable to disruption by irradiation, and was independent of spleen size. Ga-67 scintigraphy and Tc-99m sulfur colloid liver-spleen scintigraphy are two organ function-dependent imaging procedures, while CT provides anatomic information.

  17. The kinetics of phagocytosis of 198Au colloids ''in vitro''

    International Nuclear Information System (INIS)

    Astorri, N.L.; Bergoc, R.M.; Bianchin, A.M.; Caro, R.A.; Ihlo, J.E.; Rivera, E.S.

    1982-01-01

    The kinetics of the phagocytosis of 198-Au colloids by macrophages ''in vitro'' was studied by incubating during 5 hours phagocytic cells from the liver and the spleen of Wistar rats with colloidal radiogold particles, in the presence of an adequate culture medium (TC-199 with 10 per cent of Bovine Fetal Serum). In each experiment, the number of colloidal gold particles offered to each phatocytic cell, (Au) 0 and the mean rate of phagocytosis v, were calculated. The latter value was determined by measuring the radioactivity incorporated into the phagocytic cells during the incubation; it was expressed as the number of phagocytized colloidal gold particles per cell per minute. The values of log v = f [log (Au) 0 ] were plotted. The Lineweaver-Burk analysis of the results demonstrates that the kinetics of the phagocytosis of colloidal radiogold particles ''in vitro'' follows a model similar to Michaelis-Menten equations for enzyme reactions. The values of the substratum constant Ks and maximun velocity Vm were obtained by the regression analysis of the 1/v vs. 1/(Au) 0 graph. Vm was equal to 9.44 x 10 and 1.63 x 10 phagocytized colloidal gold particles per cell per minute for liver and spleen macrophages, respectively. Ks was equal to 6.01 x 10 9 and 8.02 x 10 8 colloidal gold particles per cell for liver and spleen macrophages, respectively. The significance of these differences is discussed and attributed mainly to a change of the specific engulfment rate constant. (author) [es

  18. Radiologic findings of intrapancreatic accessory spleen

    Directory of Open Access Journals (Sweden)

    Berat Acu

    2015-06-01

    Accessory spleen is a congenital abnormality consisting of normal splenic tissue in ectopic sites. They are found most commonly near the splenic hilum. One in every six accessory spleens is located in the tail of the pancreas. The diagnosis of an IPAS should be considered when a pancreatic mass has the CT densities and/or MRI signal intensities similar to those of the spleen, with and without contrast medium. [J Contemp Med 2015; 5(2.000: 140-143

  19. Assessing melioidosis using 99Tcm stannous colloid white cell scanning

    International Nuclear Information System (INIS)

    Ramsay, S.C.; La Brooy, J.; Norton, R.; Horvath, R.; Webb, B.

    2000-01-01

    Full text: Melioidosis is an infective disease endemic to tropical Australia, though also being reported with increasing frequency in temperate regions. It causes significant morbidity and mortality especially in the indigenous population. Assessment of disease extent is currently difficult especially with musculoskeletal and soft tissue disease. This study examined the usefulness of white cell scans in melioidosis. 10 patients with culture proven melioidosis were studied. Two patients had musculoskeletal/spinal disease alone, three had pulmonary disease alone, two had both, one had peritoneal abscess alone, one had intra-abdominal sepsis, pulmonary disease and musculoskeletal disease, and one had pyrexia of unknown origin. Each underwent 99 Tc m stannous colloid white cell scanning. White cell scans were compared to clinical staging, and staging using other imaging. White cell scans demonstrated all but one clinically apparent site of musculoskeletal, spinal or other soft tissue infection. The missed lesion was a very small T12 intramedullary spinal abscess obscured by physiological liver and spleen uptake. A T6-9 extradural spinal abscess in another patient was visualised. Renal disease was adequately visualised. Clinically unsuspected disseminated soft tissue lesions were seen in two patients. Unsuspected musculoskeletal disease was found in one patient, and unsuspected parotid involvement in two patients. Pulmonary disease was not necessarily associated with abnormal uptake, possibly because of delay between treatment commencement and scanning. In conclusion white cell scanning is a quick and effective way of assessing musculoskeletal and soft tissue disease in melioidosis, and can provide information that is additional to that provided by using other techniques. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  20. High dispersity of carbon nanotubes diminishes immunotoxicity in spleen.

    Science.gov (United States)

    Lee, Soyoung; Khang, Dongwoo; Kim, Sang-Hyun

    2015-01-01

    From the various physiochemical material properties, the chemical functionalization order of single-walled carbon nanotubes (swCNTs) has not been considered as a critical factor for modulating immunological responses and toxicological aspects in drug delivery applications. Although most nanomaterials, including carbon nanotubes, are specifically accumulated in spleen, few studies have focused on spleen immunotoxicity. For this reason, this study demonstrated that the dispersity of swCNTs significantly influenced immunotoxicity in vitro and in vivo. For cytotoxicity of swCNTs, MTT assay, reactive oxygen species production, superoxide dismutase activity, cellular uptake, and confocal microscopy were used in macrophages. In the in vivo study, female BALB/c mice were intravenously administered with 1 mg/kg/day of swCNTs for 2 weeks. The body weight, organ weight, hematological change, reverse-transcription polymerase chain reaction, and lymphocyte population were evaluated. Different orders of chemical functionalization of swCNTs controlled immunotoxicity. In short, less-dispersed swCNTs caused cytotoxicity in macrophages and abnormalities in immune organs such as spleen, whereas highly dispersed swCNTs did not result in immunotoxicity. This study clarified that increasing carboxyl groups on swCNTs significantly mitigated immunotoxicity in vitro and in vivo. Our findings clarified the effective immunotoxicological factors of swCNTs by increasing dispersity of swCNTs and provided useful guidelines for the effective use of nanomaterials.

  1. Colloid Transport and Retention

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander

    2012-01-01

    Book Description: Colloidal science and technology is one of the fastest growing research and technology areas. This book explores the cutting edge research in colloidal science and technology that will be usefull in almost every aspect of modern society. This book has a depth of information...... related to historical prospective, synthesis, characterization, theoretical modeling and application of unique class of colloidal materials starting from colloidal gold to coated silica colloid and platinum, titania colloids. This book is unique in its design, content, providing depth of science about...... different colloidal materials and their applications in chemistry, physics, biological, medical sciences and environment. Graduate students, academic and industrial researchers and medical professionals will discover recently developed colloidal materials and their applications in many areas of human...

  2. Colloid and surfactant

    International Nuclear Information System (INIS)

    Kuk, Yun Hwan; Lee, Jeong Jung; Cho, Sun Chae; Ryeo, Su Dong

    1995-08-01

    This book consists of two parts about colloid and surfactant. The first parts has explanations colloid and surface science, which deal with creation and properties of colloidal particles, surfactant and micelle colloid, property of surfactant, membranes, absorption of surface science, electrokinetic phenomenon, emulsion, foam and rheology. The second part mentions surfactant on anionic surfactant with five types, amphoteric surface active agent, non-ionic surface active agent and use of surfactant.

  3. Fever of unknown origin and the value of gallium-67 and technetium-99/sup m/ for defining abnormality of the spleen: a case report

    International Nuclear Information System (INIS)

    Coopersmith, A.; Ritchey, A.K.; Zinkham, W.H.

    1975-01-01

    A three-year-old white female with acute promyelocytic leukemia developed persistent fever after successful induction-remission therapy; many large monilial abscesses were later found in the grossly enlarged spleen. Although the technetium/sup 99M/-sulfur colloid scan prior to splenectomy suggested only a slight abnormality of the spleen, the gallium-67 citrate scintigraph showed a marked increase in gallium accumulation. The disparate results of the scanning techniques utilized in this patient suggest that it may be necessary to use more than one type of radiopharmaceutical to define an enlarged spleen, as well as the pathological process responsible for its enlargement

  4. Saturated Zone Colloid Transport

    Energy Technology Data Exchange (ETDEWEB)

    H. Viswanathan; P. Reimus

    2003-09-05

    Colloid retardation is influenced by the attachment and detachment of colloids from immobile surfaces. This analysis demonstrates the development of parameters necessary to estimate attachment and detachment of colloids and, hence, retardation in both fractured tuff and porous alluvium. Field and experimental data specific to fractured tuff are used for the analysis of colloid retardation in fractured tuff. Experimental data specific to colloid transport in alluvial material from Yucca Mountain as well as bacteriophage field studies in alluvial material, which are thought to be good analogs for colloid transport, are used to estimate attachment and detachment of colloids in the alluvial material. There are no alternative scientific approaches or technical methods for calculating these retardation factors.

  5. Iron colloids reduce the bioavailability of phosphorus to the green alga Raphidocelis subcapitata.

    Science.gov (United States)

    Baken, Stijn; Nawara, Sophie; Van Moorleghem, Christoff; Smolders, Erik

    2014-08-01

    Phosphorus (P) is a limiting nutrient in many aquatic systems. The bioavailability of P in natural waters strongly depends on its speciation. In this study, structural properties of iron colloids were determined and related to their effect on P sorption and P bioavailability. The freshwater green alga Raphidocelis subcapitata was exposed to media spiked with radiolabelled (33)PO4, and the uptake of (33)P was monitored for 1 h. The media contained various concentrations of synthetic iron colloids with a size between 10 kDa and 0.45 μm. The iron colloids were stabilised by natural organic matter. EXAFS spectroscopy showed that these colloids predominantly consisted of ferrihydrite with small amounts of organically complexed Fe. In colloid-free treatments, the P uptake flux by the algae obeyed Michaelis-Menten kinetics. In the presence of iron colloids at 9 or 90 μM Fe, corresponding to molar P:Fe ratios between 0.02 and 0.17, the truly dissolved P (<10 kDa) was between 4 and 60% of the total dissolved P (<0.45 μm). These colloids reduced the P uptake flux by R. subcapitata compared to colloid-free treatments at the same total dissolved P concentration. However, the P uptake flux from colloid containing solutions equalled that from colloid-free ones when expressed as truly dissolved P. This demonstrates that colloidal P did not contribute to the P uptake flux. It is concluded that, on the short term, phosphate adsorbed to ferrihydrite colloids is not available to the green alga R. subcapitata. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Colloidal-Bound Polyphosphates and Organic Phosphates Are Bioavailable: A Nutrient Solution Study.

    Science.gov (United States)

    Bollyn, Jessica; Faes, Joran; Fritzsche, Andreas; Smolders, Erik

    2017-08-16

    Colloidal forms of Fe(III) minerals can be stabilized in solution by coatings of organic or poly-phosphate (P), which reduce the zeta-potential. This opens up a route toward the development of nanoforms of P fertilizers. However, it is unclear if such P forms are bioavailable. To address this question, spinach (Spinacia oleracea) was grown in nutrient solutions, at equal total P, using three different forms of P (orthophosphate = P i ; hexametaphosphate = HMP; myo-inositol hexaphosphate = IHP), free or bound to goethite/ferrihydrite colloids. After 10 days, P uptake was determined with a dose-response curve using colloid-free P i as a reference treatment. The P i concentration generating equal P uptake as in colloidal P treatments was used to calculate the relative bioavailability of colloidal P (RBA colloid ). The RBA colloid was about 60% for P i -loaded goethite, stabilized with natural organic matter. For HMP/IHP-P i -loaded colloids, RBA colloid ranged between 10 and 50%, in line with their higher sorption strength. In conclusion, colloidal organic P or poly-P can stabilize Fe(III) colloids in solution and can contribute to plant-available P. Soil experiments are required to assess their potential as nanofertilizers.

  7. Analysis of colloid transport

    International Nuclear Information System (INIS)

    Travis, B.J.; Nuttall, H.E.

    1985-01-01

    The population balance methodology is described and applied to the transport and capture of polydispersed colloids in packed columns. The transient model includes particle growth, capture, convective transport, and dispersion. We also follow the dynamic accumulation of captured colloids on the solids. The multidimensional parabolic partial differential equation was solved by a recently enhanced method of characteristics technique. This computational technique minimized numerical dispersion and is computationally very fast. The FORTRAN 77 code ran on a VAX-780 in less than a minute and also runs on an IBM-AT using the Professional FORTRAN compiler. The code was extensively tested against various simplified cases and against analytical models. The packed column experiments by Saltelli et al. were re-analyzed incorporating the experimentally reported size distribution of the colloid feed material. Colloid capture was modeled using a linear size dependent filtration function. The effects of a colloid size dependent filtration factor and various initial colloid size distributions on colloid migration and capture were investigated. Also, we followed the changing colloid size distribution as a function of position in the column. Some simple arguments are made to assess the likelihood of colloid migration at a potential NTS Yucca Mountain waste disposal site. 10 refs., 3 figs., 1 tab

  8. UZ Colloid Transport Model

    International Nuclear Information System (INIS)

    McGraw, M.

    2000-01-01

    The UZ Colloid Transport model development plan states that the objective of this Analysis/Model Report (AMR) is to document the development of a model for simulating unsaturated colloid transport. This objective includes the following: (1) use of a process level model to evaluate the potential mechanisms for colloid transport at Yucca Mountain; (2) Provide ranges of parameters for significant colloid transport processes to Performance Assessment (PA) for the unsaturated zone (UZ); (3) Provide a basis for development of an abstracted model for use in PA calculations

  9. Colloid process engineering

    CERN Document Server

    Peukert, Wolfgang; Rehage, Heinz; Schuchmann, Heike

    2015-01-01

    This book deals with colloidal systems in technical processes and the influence of colloidal systems by technical processes. It explores how new measurement capabilities can offer the potential for a dynamic development of scientific and engineering, and examines the origin of colloidal systems and its use for new products. The future challenges to colloidal process engineering are the development of appropriate equipment and processes for the production and obtainment of multi-phase structures and energetic interactions in market-relevant quantities. The book explores the relevant processes and for controlled production and how they can be used across all scales.

  10. Autotransplant of spleen tissue in children with schistosomiasis: evaluation of splenic function after splenosis.

    Science.gov (United States)

    Brandt, C T; Maciel, D T; Caneca, O A; Castro, C M; Araújo, L B

    2001-01-01

    Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1) to study the morphology and function of the remnant spleen tissue; (2) to quantify the production of tuftsin; and (3) to assess the immune response to pneumococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 +/- 29.8 ng/ml) was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.

  11. Autotransplant of spleen tissue in children with schistosomiasis: evaluation of splenic function after splenosis

    Directory of Open Access Journals (Sweden)

    Carlos Teixeira Brandt

    2001-09-01

    Full Text Available Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1 to study the morphology and function of the remnant spleen tissue; (2 to quantify the production of tuftsin; and (3 to assess the immune response to pneomococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 ± 29.8 ng/ml was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.

  12. Preservative spleen surgery and hyperbaric oxygen therapy.

    Science.gov (United States)

    Paulo, Isabel Cristina Andreatta Lemos; Paulo, Danilo Nagib Salomão; Cintra, Luiz Cálice; Santos, Maria Carmem Silva; Rodrigues, Hildegardo; Ferrari, Thiago Antunes; Azevedo, Tiago Caetano V de; Silva, Alcino Lázaro da

    2007-01-01

    To assess functional and morphological aspects of spleen auto-implants and of the splenic inferior pole of rats, post-operatively treated or not with hyperbaric oxygen, as well as the survival of these animals, were studied. Seventy-eight male Wistar rats, weighing between 192 and 283 g ( 238,3 +/- 9,6g), were randomly distributed into three groups: Group 1--(n=20), spleen manipulation; group 2--(n=36), spleen auto-implantation; group 3--(n= 22), subtotal splenectomy preserving the inferior pole. Each group was subdivided as follows: subgroup a, not submitted to hyperbaric oxygen therapy: 1a(n=10), 2a(n=21), 3a(n= 13); subgroup b, submitted to the therapy: 1b(n=10), 2b(n=15), 3b(n=9). Blood was collected pre-operatively and 11 days after surgery, for the estimation of lipids and immunoglobulins and the counting of platelets and Howell-Jolly corpuscles. The spleen and remains were taken for histological study. The number of surviving animals was significantly higher in groups 1(p 2. The macro and microscopic appearance in subgroup 2b were more viable than in subgroup 2a, and that of group 3 more viable than in group 2. The survival of the animals carrying their whole spleen or its inferior pole was more frequent than that of the auto-implanted animals. Functionality and viability of the whole spleen or of its inferior pole, were better than in the auto-implanted animals. Hyperbaric oxygen-therapy contributed to increased survival frequency of auto-implanted animals, and to improve the functionality and viability of the auto-implants and the function of the inferior splenic pole, and did not interfere in animals carrying their whole spleen.

  13. Spleen-preserving distal pancreatectomy in trauma.

    Science.gov (United States)

    Schellenberg, Morgan; Inaba, Kenji; Cheng, Vincent; Bardes, James M; Lam, Lydia; Benjamin, Elizabeth; Matsushima, Kazuhide; Demetriades, Demetrios

    2018-01-01

    Traumatic injuries to the distal pancreas are infrequent. Universally accepted recommendations about the need for routine splenectomy with distal pancreatectomy do not exist. The aims of this study were to compare outcomes after distal pancreatectomy and splenectomy versus spleen-preserving distal pancreatectomy, and to define the appropriate patient population for splenic preservation. All patients who underwent distal pancreatectomy (January 1, 2007, to December 31, 2014) were identified from the National Trauma Data Bank. Patients with concomitant splenic injury and those who underwent partial splenectomy were excluded. Demographics, clinical data, procedures, and outcomes were collected. Study groups were defined by surgical procedure: distal pancreatectomy and splenectomy versus spleen-preserving distal pancreatectomy. Baseline characteristics between groups were compared with univariate analysis. Multivariate analysis was performed with logistic and linear regression to examine differences in outcomes. Over the 8-year study period, 2,223 patients underwent distal pancreatectomy. After excluding 1,381 patients with concomitant splenic injury (62%) and 8 (pancreatectomy and splenectomy, those who underwent spleen-preserving distal pancreatectomy were younger (p pancreatectomy (p = 0.017). Complications, mortality, and intensive care unit LOS were not significantly different. In young patients after blunt trauma who are not severely injured, a spleen-preserving distal pancreatectomy should be considered to allow for conservation of splenic function and a shorter hospital LOS. In all other patients, the surgeon should not hesitate to remove the spleen with the distal pancreas. Therapy, level IV.

  14. Solid solitary hamartoma of the spleen

    Directory of Open Access Journals (Sweden)

    Grubor Nikica

    2013-01-01

    Full Text Available Introduction. Hamartoma of the spleen is a rare, sometimes asymptomatic similar to hemangioma benign tumor of the spleen, which, owing to the new diagnostic imaging methods, is discovered with increasing frequency. It appears as solitary or multiple tumorous lesions. Case Outline. We present a 48-year-old woman in whom, during the investigation for Helicobacter pylori gastric infection and rectal bleeding, with ultrasonography, a mass 6.5×6.5 cm in diameter was discovered by chance within the spleen. Splenectomy was performed due to suspected lymphoma of the spleen. On histology, tumor showed to be of mixed cellular structure, with areas without white pulp, at places with marked dilatation of sinusoids and capillaries to the formation of „blood lakes“ between which broad hypercellular Billroth’s zones were present. Extramedullary hematopoiesis was found focally. The cells that covered vascular spaces were CD34+ and CD31+ and CD8- and CD21-. Conclusion. Hamartoma has to be taken into consideration always when well circumscribed hypervascular tumor within the spleen is found, particularly in children. Although the diagnosis of hamartoma may be suspected preoperatively, the exact diagnosis is established based on histological and immunohystochemistry examinations. Treatment is most often splenectomy and rarely a partial splenectomy is possible, which is recommended particularly in children.

  15. The comparative immunotoxicity of mesoporous silica nanoparticles and colloidal silica nanoparticles in mice

    Directory of Open Access Journals (Sweden)

    Lee S

    2013-01-01

    Full Text Available Soyoung Lee,1,* Mi-Sun Kim,1,* Dakeun Lee,2 Taeg Kyu Kwon,3 Dongwoo Khang,4 Hui-Suk Yun,5 Sang-Hyun Kim11CMRI, Laboratory of Immunotoxicology, Department of Pharmacology,School of Medicine, Kyungpook National University, Daegu, Republic of Korea; 2Department of Pathology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea; 3Department of Immunology, School of Medicine, Keimyung University, Daegu, Republic of Korea; 4School of Nano and Advanced Materials Science and Engineering, Gyeongsang National University, Jinju, Republic of Korea; 5Engineering Ceramics Department, Powder and Ceramics Division, Korea Institute of Materials Science, Changwon, Republic of Korea*These authors contributed equally to this workBackground: Mesoporous silica (MPS nanoparticles (NPs, which have a unique pore structure and extremely large surface area and pore volume, have received much attention because of their biomedical application potential. Using MPS NPs for biomedical devices requires the verification of their biocompatibility because the surface area of NPs is one of the most important determinants of toxicity, including the cellular uptake and immune response. We have previously reported that the cytotoxicity and inflammation potential of MPS NPs have been shown to be lower than those of general amorphous colloidal silica (Col NPs in macrophages, but the low cytotoxicity does not guarantee high biocompatibility in vivo. In this study, we compared the in vivo immunotoxicity of MPS and Col NPs in the mouse model to define the effects of pore structural conditions of silica NPs.Materials and methods: Both MPS and Col NPs (2, 20, and 50 mg/kg/day were intraperitoneally administered in female BALB/c mice for 4 weeks, and clinical toxicity, lymphocyte population, serum IgG/IgM levels, and histological changes were examined.Results: There was no overt sign of clinical toxicity in either MPS- or Col-treated mice. However, MPS NPs led to

  16. Interface colloidal robotic manipulator

    Science.gov (United States)

    Aronson, Igor; Snezhko, Oleksiy

    2015-08-04

    A magnetic colloidal system confined at the interface between two immiscible liquids and energized by an alternating magnetic field dynamically self-assembles into localized asters and arrays of asters. The colloidal system exhibits locomotion and shape change. By controlling a small external magnetic field applied parallel to the interface, structures can capture, transport, and position target particles.

  17. [Pyoderma gangrenosum with aseptic spleen abscess].

    Science.gov (United States)

    Brahimi, N; Maubec, E; Boccara, O; Marinho, E; Valeyrie-Allanore, L; Lecaille, C; Sebban, V; Hersent, B; Picard-Dahan, C; Descamps, V; Crickx, B

    2009-01-01

    Pyoderma gangrenosum is a neutrophilic dermatosis in which systemic involvement is rare. It may be associated with systemic disease. We report a case of pyoderma gangrenosum in the spleen. A 68-year-old man presenting pyoderma gangrenosum with pustules and stage I multiple myeloma was admitted for asthenia and abdominal pain. There were no skin lesions. Laboratory tests showed inflammatory syndrome with polynuclear leucocytes of 25,000/mm(3). CAT scans and abdominal ultrasound revealed a splenic abscess. A spleen biopsy was performed and histological examination showed polynuclear leukocyte infiltration, while cultures were negatives. Diagnosis of pyoderma gangrenosum with splenic involvement was made. Increased systemic corticosteroid therapy produced a successful outcome. Haematological findings remained unchanged. Spleen involvement in pyoderma gangrenosum is very rare and can mimic an infectious process. In such cases, routine screening is essential for associated diseases, particularly haematological malignancies.

  18. Function of the replanted spleen in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Velcek, F.T.; Kugaczewski, J.T.; Jongco, B.; Shaftan, G.W.; Rao, P.S.; Schiffman, G.; Kottmeier, P.K.

    1982-06-01

    The function of replanted splenic fragments was studied by comparing three groups of five dogs each, one group with intact spleens; one, post-splenectomy; and one with splenic replantation. Fifteen fragments were implanted into the omentum. Howell-Jolly bodies appeared after splenectomy but cleared in the replanted group after several months. /sup 125/I-tagged attenuated pneumococcal clearance studies showed a significant difference between control and replanted group compared with the splenectomized group. The increase of pneumococcal antibody titers after vaccination differed significantly between the splenectomized and the replanted group. All replanted fragments were viable and showed growth over a 2-year period. These studies demonstrate that omental replantation of the canine spleen leads to the maintenance of certain functional splenic parameters comparable to the normal spleen which are significantly different from the splenectomized animal.

  19. Laparoscopic Splenectomy in Patients With Spleen Injuries.

    Science.gov (United States)

    Ermolov, Aleksander S; Tlibekova, Margarita A; Yartsev, Peter A; Guliaev, Andrey A; Rogal, Mikhail M; Samsonov, Vladimir T; Levitsky, Vladislav D; Chernysh, Oleg A

    2015-12-01

    Spleen injury appears in 10% to 30% of abdominal trauma patients. Mortality among the patients in the last 20 years remains high (6% to 7%) and shows no tendency to decline. Nowadays nonoperative management is widely accepted management of patients with low-grade spleen injury, whereas management of patients with high-grade spleen injury (III and higher) is not so obvious. There are 3 methods exist in treatment of such patients: conservative (with or without angioembolization), spleen-preserving operations, and splenectomy. Today laparoscopic splenectomy is not a widely used operation and only few studies reported about successful use of laparoscopic splenectomy in patients with spleen injury.The aim of the study was to determine indications and contraindications for laparoscopic splenectomy in abdominal trauma patients and to analyze results of the operations. The study involved 42 patients with spleen injury grade III who were admitted in our institute in the years of 2010 to 2014. The patients were divided in 2 groups. Laparoscopic splenectomy was performed in 23 patients (group I) and "traditional" splenectomy was carried out in 19 patients (group II). There was no difference in the demographic data and trauma severity between the 2 groups. Noninvasive investigations, such as laboratory investigations, serial abdominal ultrasound examinations, x-ray in multiple views, and computed tomography had been performed before the decision about necessity of an operation was made. Patients after laparoscopic operations had better recovering conditions compared with patients with the same injury after "traditional" splenectomy. Neither surgery-related complications nor mortalities were registered in both groups. Laparoscopic splenectomy was more time-consuming operation than "traditional" splenectomy. We suggest that as experience of laparoscopic splenectomy is gained the operation time will be reduced. Laparoscopic splenectomy is a safe feasible operation in patients

  20. The onset of hemoglobin synthesis in spleens of irradiated mice after bone marrow transplantation

    International Nuclear Information System (INIS)

    Ponka, P.; Fuchs, O.; Borova, J.; Necas, E.

    1977-01-01

    Messenger RNA (mRNA) for globin was isolated from spleens of irradiated mice in which erythroid differentiation was induced by a bone marrow graft. The globin mRNA was isolated either by means of sucrose gradients of reticulocyte polysomal RNA or by affinity chromatography of total spleen RNA on poly (U)-sepharose. The globin mRNA was tested in a wheat embryo cell-free system. The appearance of mRNA in the spleen erythroid colonies was correlated with other parameters of erythroid differentiation such as globin synthesis, activity of delta-aminolevulinic acid synthetase and iron uptake. Poly(A) containing mRNA did appear already on the 3rd day after grafting. However, significant translational activity of globin mRNA could be demonstrated only one day later together with increase in globin synthesis and delta-aminolevulinic acid synthetase and enhanced iron uptake. In the second part of this study mouse spleen cells rich in erythroid elements were incubated with a specific heme synthesis inhibitor (isonicotinic acid hydrazide, INH) and the synthesis of 9 S RNA was estimated. It was found that a 40-minute incubation with INH reduced uridine incorporation into 9 S RNA fraction by about 40%. (author)

  1. Colloidal Plasmas: Basic physics of colloidal plasmas

    Indian Academy of Sciences (India)

    The present contribution will review the basic physics of the charging mechanism of the colloidal particles as well as the physics of the collective normal mode behavior of the general multi-ion species plasmas. Emphasis will be laid on the clarification of the prevailing confusing ideas about distinct qualities of the various ...

  2. Saturated Zone Colloid Transport

    Energy Technology Data Exchange (ETDEWEB)

    H. S. Viswanathan

    2004-10-07

    This scientific analysis provides retardation factors for colloids transporting in the saturated zone (SZ) and the unsaturated zone (UZ). These retardation factors represent the reversible chemical and physical filtration of colloids in the SZ. The value of the colloid retardation factor, R{sub col} is dependent on several factors, such as colloid size, colloid type, and geochemical conditions (e.g., pH, Eh, and ionic strength). These factors are folded into the distributions of R{sub col} that have been developed from field and experimental data collected under varying geochemical conditions with different colloid types and sizes. Attachment rate constants, k{sub att}, and detachment rate constants, k{sub det}, of colloids to the fracture surface have been measured for the fractured volcanics, and separate R{sub col} uncertainty distributions have been developed for attachment and detachment to clastic material and mineral grains in the alluvium. Radionuclides such as plutonium and americium sorb mostly (90 to 99 percent) irreversibly to colloids (BSC 2004 [DIRS 170025], Section 6.3.3.2). The colloid retardation factors developed in this analysis are needed to simulate the transport of radionuclides that are irreversibly sorbed onto colloids; this transport is discussed in the model report ''Site-Scale Saturated Zone Transport'' (BSC 2004 [DIRS 170036]). Although it is not exclusive to any particular radionuclide release scenario, this scientific analysis especially addresses those scenarios pertaining to evidence from waste-degradation experiments, which indicate that plutonium and americium may be irreversibly attached to colloids for the time scales of interest. A section of this report will also discuss the validity of using microspheres as analogs to colloids in some of the lab and field experiments used to obtain the colloid retardation factors. In addition, a small fraction of colloids travels with the groundwater without any significant

  3. Distal splenorenal shunt with partial spleen resection

    Directory of Open Access Journals (Sweden)

    Gajin Predrag

    2007-01-01

    Full Text Available Introduction: Hypersplenism is a common complication of portal hypertension. Cytopenia in hypersplenism is predominantly caused by splenomegaly. Distal splenorenal shunt (Warren with partial spleen resection is an original surgical technique that regulates cytopenia by reduction of the enlarged spleen. Objective. The aim of our study was to present the advantages of distal splenorenal shunt (Warren with partial spleen resection comparing morbidity and mortality in a group of patients treated by distal splenorenal shunt with partial spleen resection with a group of patients treated only by a distal splenorenal shunt. Method. From 1995 to 2003, 41 patients with portal hypertension were surgically treated due to hypersplenism and oesophageal varices. The first group consisted of 20 patients (11 male, mean age 42.3 years who were treated by distal splenorenal shunt with partial spleen resection. The second group consisted of 21 patients (13 male, mean age 49.4 years that were treated by distal splenorenal shunt only. All patients underwent endoscopy and assessment of oesophageal varices. The size of the spleen was evaluated by ultrasound, CT or by scintigraphy. Angiography was performed in all patients. The platelet and white blood cell count and haemoglobin level were registered. Postoperatively, we noted blood transfusion, complications and total hospital stay. Follow-up period was 12 months, with first checkup after one month. Results In the first group, only one patient had splenomegaly postoperatively (5%, while in the second group there were 13 patients with splenomegaly (68%. Before surgery, the mean platelet count in the first group was 51.6±18.3x109/l, to 118.6±25.4x109/l postoperatively. The mean platelet count in the second group was 67.6±22.8x109/l, to 87.8±32.1x109/l postoperatively. Concerning postoperative splenomegaly, statistically significant difference was noted between the first and the second group (p<0.05. Comparing the

  4. Colloids in Biotechnology

    CERN Document Server

    Fanun, Monzer

    2010-01-01

    Colloids have come a long way from when Thomas Graham coined the term colloid to describe 'pseudo solutions'. This book enables scientists to close the gap between extensive research and translation into commercial options in biomedicine and biotechnology. It covers biosurfactants and surface properties, phase behavior, and orientational change of surfactant mixtures with peptides at the interface. It also covers adsorption of polymers and biopolymers on the surface and interface, discusses colloidal nanoparticles and their use in biotechnology, and delves into bioadhesion and microencapsulati

  5. Colloids or artefacts?

    International Nuclear Information System (INIS)

    Laaksoharju, M.; Vuorinen, U.; Allard, B.; Pettersson, C.; Hinkkanen, H.

    1994-01-01

    TVO (Teollisuuden Voima Oy, Finland) initiated a co-operative task with SKB (Swedish Nuclear Fuel and Waste Management Co.) to critically evaluate colloid sampling methods at the test site in Olkiluoto, SW Finland. Three different colloid sampling methods were compared when sampling at 613-618 m depth. The colloid sampling consisted of ordinary filtering (cross-flow filtering, 20-450 nm) in open air, inert filtering (cross-flow filtering, prefilter=2500 nm, separate filtration to three fractions 50,200 and 400 nm) by using N 2 and ultrafiltration (tangential filtering, prefilter=1000 nm concentration to a single fraction 2-1000 nm) using N 2 . Two samples per method were taken with an interval of three weeks. For organic determination one sample was collected. Care was taken to avoid possible known artefacts in connection with the colloid sampling. (27 refs., 31 figs., 13 tabs.)

  6. Liquid crystal colloids

    CERN Document Server

    Muševič, Igor

    2017-01-01

    This book brings together the many concepts and discoveries in liquid crystal colloids contributed over the last twenty years and scattered across numerous articles and book chapters. It provides both a historical overview of the development of the field and a clear perspective on the future applications in photonics. The book covers all phenomena observed in liquid crystal colloids with an emphasis on experimental tools and applications of topology in condensed matter, as well as practical micro-photonics applications. It includes a number of spectacular manifestations of new topological phenomena not found or difficult to observe in other systems. Starting from the early works on nematic colloids, it explains the basics of topological defects in ordered media, charge and winding, and the elastic forces between colloidal particles in nematics. Following a detailed description of experimental methods, such as optical tweezing and particle tracking, the book eases the reader into the theoretical part, which de...

  7. Fabrication of anisotropic multifunctional colloidal carriers

    Science.gov (United States)

    Jerri, Huda A.

    The field of colloidal assembly has grown tremendously in recent years, although the direct or template-assisted methods used to fabricate complex colloidal constructions from monodisperse micro- and nanoparticles have been generally demonstrated on model materials. In this work, novel core particle syntheses, particle functionalizations and bottom-up assembly techniques are presented to create functional colloidal devices. Using particle lithography, high-information colloidal vectors have been developed and modified with imaging and targeting agents. Localized nanoscale patches have been reliably positioned on microparticles to serve as foundations for further chemical or physical modifications. Site-specific placement of RGD targeting ligands has been achieved in these lithographed patches. Preferential uptake of these targeted vectors by RGD-specific 3T3 fibroblasts was verified using confocal laser scanning microscopy. A transition was made from the functionalization of model imaging core particles to the lithography of colloidal cartridges, in an effort to construct colloidal syringes with specialized, programmable release profiles. A variety of functional, pH-sensitive fluorescent cores were engineered to respond to solution conditions. When triggered, the diverse composite core microparticles and reservoir microcapsules released embedded fluorescent moieties such as dye molecules, and fluorophore-conjugated nanoparticles. The microcapsules, created using layer-by-layer polyelectrolyte deposition on sacrificial templates, were selectively modified with a robust coating. The pH-responsive anisotropic reservoir microcapsules were extremely stable in solution, and exhibited a "Lazarus" functionality of rehydrating to their original state following desiccation. A snapshot of focused-release of core constituents through the lone opening in colloidal monotremes has been obtained by anisotropically-functionalizing degradable cores with barrier shells. Additionally

  8. Waveguides in colloidal nanosuspensions

    Science.gov (United States)

    López-Peña, Luis A.; Salazar-Romero, Yadira; Terborg, Roland A.; Hernández-Cordero, Juan; Torres, Juan P.; Volke-Sepúlveda, K.

    2014-09-01

    We present and discuss a set of experiments based on the application of the nonlinear properties of colloidal nanosuspensions to induce waveguides with a high-power CW laser beam (wavelength 532nm) and its use for controlling an additional probe beam. The probe is a CW laser of a different wavelength (632nm), whose power is well below the critical value to induce nonlinear effects in the colloidal medium. We also discuss a technique for the characterization of the induced waveguides.

  9. Howell-Jolly bodies and liver-spleen scanning for assessment of splenic filtrative function yields discordant results in renal transplant recipients.

    Science.gov (United States)

    Araújo, Nordeval Cavalcante; Orlando, Margarida Maria Camões; Neves, Moises Bonifácio; Rioja, Suzimar Silveira; de Lucena, Stella Beatriz Gonçalves; Mandarim-de-Lacerda, Carlos Alberto

    2017-12-01

    Given discrepancies between methods for diagnosing hyposplenism, the purpose of this study was to evaluate the effect of the spleen size on the correlation between the methods, and to propose a model for improving the interpretation. Patients with renal allografts were included, in whom the spleen was assessed using Doppler ultrasound, scintiscan, and the presence of Howell-Jolly bodies (HJBs) in peripheral smears. In 35 subjects, scintiscan and HJBs were normal (Group 0); 20 had an abnormal result in both methods (Group 1); 34 had discordant results with HJBs present (Group 2); and 14 had discordant results with decreased spleen uptake (Group 3). There was no association between HJBs and scintiscan. The patients of Groups 1 and 2 had smaller spleens. The patients with smaller spleen had more hematological evidence of hyposplenism and exhibit smaller discrepancies between the methods than patients with larger spleen. The spleen can tip the balance from a normal to impaired function provided that the spleen size is below the critical mass required to maintain splenic function. A mild impairment of phagocytic function and slight dyserythropoiesis along with a small spleen would result in decreased take up of radiocolloid or the appearance of HJBs in blood smears. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  10. Kinetics of phagocytosis of /sup 198/Au colloids ''in vitro''

    Energy Technology Data Exchange (ETDEWEB)

    Astorri, N.L.; Bergoc, R.M.; Bianchin, A.M.; Caro, R.A.; Ihlo, J.E.; Rivera, E.S. (Buenos Aires Univ. Nacional (Argentina). Facultad de Farmacia y Bioquimica)

    1982-07-01

    The kinetics of the phagocytosis of 198-Au colloids by macrophages ''in vitro'' was studied by incubating during 5 hours phagocytic cells from the liver and the spleen of Wistar rats with colloidal radiogold particles, in the presence of an adequate culture medium (TC-199 with 10 per cent of Bovine Fetal Serum). In each experiment, the number of colloidal gold particles offered to each phatocytic cell, (Au)/sub 0/ and the mean rate of phagocytosis v, were calculated. The latter value was determined by measuring the radioactivity incorporated into the phagocytic cells during the incubation; it was expressed as the number of phagocytized colloidal gold particles per cell per minute. The values of log v = f (log (Au)/sub 0/) were plotted. The Lineweaver-Burk analysis of the results demonstrates that the kinetics of the phagocytosis of colloidal radiogold particles ''in vitro'' follows a model similar to Michaelis-Menten equations for enzyme reactions. The values of the substratum constant Ks and maximun velocity Vm were obtained by the regression analysis of the 1/v vs. 1/(Au)/sub 0/ graph. Vm was equal to 9.44 x 10 and 1.63 x 10 phagocytized colloidal gold particles per cell per minute for liver and spleen macrophages, respectively. Ks was equal to 6.01 x 10/sup 9/ and 8.02 x 10/sup 8/ colloidal gold particles per cell for liver and spleen macrophages, respectively. The significance of these differences is discussed and attributed mainly to a change of the specific engulfment rate constant.

  11. Sonographic assessment and grading of spleen index in various diseases

    Directory of Open Access Journals (Sweden)

    Rohani N

    2000-07-01

    Full Text Available Ultrasonography is a useful procedure in evaluation of spleen size in different clinical conditions. In this study, we used it to evaluate spleen size in patients with various heptologic, hematologic and autoimmune diseases. To express spleen size, a spleen index (SI, the product of the transverse diameter and its perpendiculr diameter measured on the maximum-sectional image of the spleen, was used. Splenomegaly was present in high percentages of patients with liver, blood, collagen or autoimmune diseases, even though a majority of these spleens were not large enough to palpate. By grading the SI, characteristic distributions of SI were obtained for patients with different types of diseases. Obtaining and grading the SI by the use of ultrasound appears to be a significant supplemental aid for evaluating spleen size, especially in patients whose spleen are not palpable.

  12. Wandering spleen with a ten-time twisted vascular pedicle

    Directory of Open Access Journals (Sweden)

    Marta Peretti

    2016-12-01

    Full Text Available Torsion of a wandering spleen is a rare cause of acute abdomen in children, usually diagnosed with color-Doppler ultrasonography and enhanced computed tomography. We report a pediatric case of torsion of wandering spleen.

  13. Value of transoperative scintigraphy in the detection of accessory spleens

    International Nuclear Information System (INIS)

    Sezeur, A.; Goujard, F.; Labriolle-Vaylet, C.L. de; Wioland, M.; Douay, L.; Desmarquet, J.

    1990-01-01

    A case of accessory spleen, 1 cm in diameter, responsible for recurrence of an idiopathic thrombocytopenic purpura after splenectomy is reported. This case is original in that the accessory spleen could only be detected by transoperative scintigraphy. Transoperative scintigraphy is a simple method to be used when one or several unrecognized accessory spleens are responsible for recurrence of a blood disease after excision of the principal spleen [fr

  14. Actinide colloid generation in groundwater

    International Nuclear Information System (INIS)

    Kim, J.I.

    1990-05-01

    The progress made in the investigation of actinide colloid generation in groundwaters is summarized and discussed with particular examples relevant to an understanding of the migration behaviour of actinides in natural aquifer systems. The first part deals with the characterization of colloids: groundwater colloids, actinide real-colloids and actinide pseudocolloids. The second part concentrates on the generation processes and migration behaviour of actinide pseudocolloids, which are discussed with some notable experimental examples. Importance is stressed more on the chemical aspects of the actinide colloid generation in groundwater. This work is a contribution to the CEC project MIRAGE II, particularly, to research area: complexation and colloids. (orig.)

  15. Wandering Spleen with Splenic Vein Thrombosis: A Case Report ...

    African Journals Online (AJOL)

    A wandering spleen is a rare clinical occurrence with fewer than 500 cases reported and an incidence of less than 0.2%1, 2. The spleen is an important component of the reticuloendothelial system, which is involved in immunological defence and can serve as a storage site for red blood cells3. The spleen is normally ...

  16. A wandering spleen presenting as a hypogastric mass: Case report ...

    African Journals Online (AJOL)

    ... the spleen. A 26-year-old woman was admitted to our hospital with vomiting and abdominal pain. Abdominal examination revealed a large ovoid hypogastric mass. A CT scan showed a wandering spleen in the hypogastric region. Exploratory laparotomy revealed an ischemic spleen. A total splenectomy was performed.

  17. Nematic Liquid-Crystal Colloids.

    Science.gov (United States)

    Muševič, Igor

    2017-12-25

    This article provides a concise review of a new state of colloidal matter called nematic liquid-crystal colloids. These colloids are obtained by dispersing microparticles of different shapes in a nematic liquid crystal that acts as a solvent for the dispersed particles. The microparticles induce a local deformation of the liquid crystal, which then generates topological defects and long-range forces between the neighboring particles. The colloidal forces in nematic colloids are much stronger than the forces in ordinary colloids in isotropic solvents, exceeding thousands of k B T per micrometer-sized particle. Of special interest are the topological defects in nematic colloids, which appear in many fascinating forms, such as singular points, closed loops, multitudes of interlinked and knotted loops or soliton-like structures. The richness of the topological phenomena and the possibility to design and control topological defects with laser tweezers make colloids in nematic liquid crystals an excellent playground for testing the basic theorems of topology.

  18. Blood leukocyte and spleen lymphocyte immune response of spleen lymphocytes and whole blood leukocytes of hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Peters, B.A.; Sothmann, M.; Wehrenberg, W.B. (Univ. of Wisconsin, Milwaukee (USA))

    1989-01-01

    This study was designed to evaluate the effects of chronic physical activity on the immune response of spleen lymphocytes and whole blood leukocytes of hamsters. Animals were kept sedentary or allowed to exercise spontaneously on running wheels for eight weeks. Physically active animals averaged 12 kilometers per day. The immune response of spleen lymphocytes whole blood leukocytes was evaluated by {sup 3}H-thymidine incorporation in response to Concanavalin A or lipopolysaccharide. There was no treatment effect between physically active and sedentary hamster in response of spleen lymphocytes. The immune response of whole blood leukocytes to these mitogens was significantly greater in physically active vs. sedentary hamsters. These results demonstrate that chronic physical activity has the capacity to modulate immunoresponses.

  19. Reversible functional asplenia in chronic aggressive hepatitis. [/sup 99m/Tc-sulfur colloid

    Energy Technology Data Exchange (ETDEWEB)

    Dhawan, V.M.; Spencer, R.P.; Sziklas, J.J.

    1979-01-01

    A 61-year-old man was presented with aggressive hepatitis. Howell--Jolly bodies were present in circulating erythrocytes and the spleen failed to accumulate intravenously administered Tc-99m sulfur colloid. The patient thus demonstrated functional asplenia. He was treated with high doses of steroids. Four years later, Howell--Jolly bodies were no longer present in circulating erythrocytes. In addition, the spleen had regained the ability to accumulate intravenously injected radiocolloid. Hence, the patient had reversed his functional asplenia. The reported cases of this disorder (reversible functional asplenia) were reviewed and a preliminary classification was proposed.

  20. Relationship between number of spleen colonies and 125IdUrd incorporation into spleen and femur

    International Nuclear Information System (INIS)

    Inoue, T.; Bullis, J.E.; Cronkite, E.P.; Hubner, G.E.

    1983-01-01

    Graded numbers of bone marrow (BM) cells were injected into fatally irradiated mice. Eight days later the mice were given 3.0 μCi (1 Ci = 3.7 x 10 10 Bq) of 125 IdUrd to label proliferating cells in the spleen and BM. On day 9 the mice were killed and the spleens and femurs were removed for splenic colony assay and measurement of radioactivity in the spleen and femurs. The number of splenic colonies shows a linear relationship with dose of marrow cells injected from 10 4 to 10 5 cells. The slope of the curve of spleen colonies versus number of cells injected is 5 and below 10 4 there is a striking departure from the simple linearity. Below 2 x 10 3 cells injected, the logarithm of the observed colony yield is linear with logarithm of the number of cells injected. Poisson calculation of the average number of pluripotent stem cells that should be present with numbers of marrow cells injected below 2 x 10 3 followed closely the actual observations. The data show that there is no detectible proliferation in the BM until the dose of marrow cells exceeds 3.5 x 10 4 cells. Induction of cells into cycle increases the seeding into the BM, and thymidine cytocide drastically reduces seeding in the BM, leading us to conclude that the BM is repopulated almost exclusively by stem cells in DNA synthesis

  1. Medical applications of colloids

    CERN Document Server

    Matijevic, Egon

    2008-01-01

    The first book of its type on the medical and biomedical applications of colloids, although there are some related titles on different topicsDiscusses the effects of uniform particles in drug formulations and releaseEvaluates particle transport and deposition in the human body.

  2. Binary colloidal crystals

    NARCIS (Netherlands)

    Christova-Zdravkova, C.G.

    2005-01-01

    Binary crystals are crystals composed of two types of particles having different properties like size, mass density, charge etc. In this thesis several new approaches to make binary crystals of colloidal particles that differ in size, material and charge are reported We found a variety of crystal

  3. Enhanced transport of ferrihydrite colloid by chain-shaped humic acid colloid in saturated porous media.

    Science.gov (United States)

    Ma, Jie; Guo, Huaming; Lei, Mei; Li, Yongtao; Weng, Liping; Chen, Yali; Ma, Yuling; Deng, Yingxuan; Feng, Xiaojuan; Xiu, Wei

    2018-04-15

    Both humic acid and colloid particle size effectively regulate colloid transport. However, little is known about effect of particle size and configuration of humic acid colloid (HA colloid ) on enhanced-transport of ferrihydrite colloid (FH colloid ) in porous media. Co-transport of HA colloid and FH colloid at different pH was systematically investigated by monitoring breakthrough curves (BTCs) in saturated sand columns. The colloid transport model and the (X)DLVO theory were used to reveal the mechanism of HA colloid -enhanced FH colloid transport in the columns. Results showed that HA colloid enhanced FH colloid transport in neutral and alkaline conditions. In neutral conditions, small HA colloid (F-HA colloid ) with chain-shaped structure enhanced FH colloid transport more prominently than pristine granular HA colloid . The chain-shaped F-HA colloid caused osmotic repulsion and elastic-steric repulsion between colloids and sand, leading to enhanced transport. However, the granular HA colloid readily occurred as deposition due to attachment and straining, which decreased the enhanced transport of FH colloid . In alkaline conditions, both HA colloid and F-HA colloid were chain-shaped, with longer chains of HA colloid than F-HA colloid . Ferrihydrite colloid transport was enhanced by HA colloid more significantly than F-HA colloid due to stronger repulsion between mixed HA colloid -FH colloid and sand. It suggested that regulation of particle size and morphology of HA colloid would enhance FH colloid transport and further help in understanding FH colloid -facilitated contaminants transport in porous media. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. [Delayed rupture of the spleen in a multiply injured patient].

    Science.gov (United States)

    Lică, I; Venter, M D; Mehic, R; Marian, R; Ionescu, G

    1997-01-01

    The authors present a case of delayed rupture of the spleen in a polytraumatised patient. This entity was defined as a late occurrence of signs and symptoms attributed to splenic injury not detected by diagnostic computed tomographic scanning during the initial examination. The mechanisms in which the delayed rupture of the spleen occurs are discussed and the conclusion is that the delayed rupture of the spleen represent a real clinical entity.

  5. Evaluation of Spleen Glucose Metabolism Using18F-FDG PET/CT in Patients with Febrile Autoimmune Disease.

    Science.gov (United States)

    Ahn, Sung Soo; Hwang, Sang Hyun; Jung, Seung Min; Lee, Sang-Won; Park, Yong-Beom; Yun, Mijin; Song, Jason Jungsik

    2017-03-01

    The purpose of this study was to evaluate the clinical significance of 18 F-FDG uptake by the spleen in patients with autoimmune disease. Methods: We retrospectively reviewed Severance Hospital's electronic medical records of patients hospitalized for the evaluation of fever who underwent 18 F-FDG PET/CT. We found 91 patients with autoimmune diseases and 101 patients with localized infection. 18 F-FDG uptake was assessed by measuring SUV in the spleen and liver. The spleen-to-liver ratio of the SUV mean (SLR mean ) was calculated. Clinical and laboratory parameters were collected and evaluated for association with SLR mean In-hospital mortality was defined as all-cause mortality during hospital admission for fever. Results: SLR mean was significantly higher in autoimmune disease than in localized infectious disease (1.28 ± 0.43 vs. 0.91 ± 0.21, P autoimmune disease, SLR mean was correlated with monocytes, aspartate aminotransferase, alanine aminotransferase, albumin, and ferritin. Analysis of receiver-operating-characteristic curves revealed that in comparison with laboratory parameters, SLR mean had the highest performance in differentiating autoimmune from localized infectious disease. Multivariate logistic regression analysis demonstrated that high SLR mean and low platelets were significantly associated with in-hospital mortality in febrile autoimmune disease. Conclusion: These findings suggest that spleen glucose metabolism is increased in febrile autoimmune disease. Spleen 18 F-FDG uptake may provide information useful in differentiating febrile autoimmune disease from localized infectious disease and predicting clinical outcomes in febrile autoimmune disease. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  6. Wandering spleen: a medical enigma, its natural history and rationalization.

    Science.gov (United States)

    Magowska, Anita

    2013-03-01

    Wandering spleen is a rare condition in which the spleen is not located in the left upper quadrant but is found lower in the abdomen or in the pelvic region because of the laxity of the peritoneal attachments. Many patients with wandering spleen are asymptomatic, hence the condition can be discovered only by abdominal examination or at a hospital emergency department if a patient is admitted to hospital because of severe abdominal pain, vomiting or obstipation. This article aims to provide a historical overview of wandering spleen diagnostics and surgical treatment supplemented with an analyses of articles on wandering spleen included in the PubMed database. One of the first clinical descriptions of a wandering spleen was written by Józef Dietl in 1854. The next years of vital importance are 1877 when A. Martin conducted the first splenectomy and in 1895 when Ludwik Rydygier carried out the first splenopexy to immobilize a wandering spleen. Since that time various techniques of splenectomy and splenopexy have been developed. Introducing medical technologies was a watershed in the development and treatment of wandering spleen, which is confirmed by the PubMed database. Despite the increased number of publications medical literature shows that a wandering spleen still remains a misdiagnosed condition, especially among children.

  7. Producing colloids with microfluidics

    Science.gov (United States)

    Pannacci, Nicolas; Willaime, Herve; Tabeling, Patrick

    2008-11-01

    Submicronic emulsions are commonly used in pharmaceutical, food, cosmetic and material industries. Standard microfluidic tool is particularly convenient to produce in a very controlled way either droplets of typical diameter ranging from 10 to 300 microns with a perfect monodispersity (nanodrops in a way that is slightly dependent on the fluids used. The control on such a flow authorizes the adjustment of the diameter of the colloids formed. We will show brownian particles from 860 nm to 1.3 μm in diameter obtained in such way and their clustering into crystals thanks to their high monodispersity. These first experimental results are very promising and make evident the great potential of micro and nano-fluidics to produce nano-emulsions or colloids with very controlled size that metamaterials can require.

  8. Fractal nematic colloids

    Science.gov (United States)

    Hashemi, S. M.; Jagodič, U.; Mozaffari, M. R.; Ejtehadi, M. R.; Muševič, I.; Ravnik, M.

    2017-01-01

    Fractals are remarkable examples of self-similarity where a structure or dynamic pattern is repeated over multiple spatial or time scales. However, little is known about how fractal stimuli such as fractal surfaces interact with their local environment if it exhibits order. Here we show geometry-induced formation of fractal defect states in Koch nematic colloids, exhibiting fractal self-similarity better than 90% over three orders of magnitude in the length scales, from micrometers to nanometres. We produce polymer Koch-shaped hollow colloidal prisms of three successive fractal iterations by direct laser writing, and characterize their coupling with the nematic by polarization microscopy and numerical modelling. Explicit generation of topological defect pairs is found, with the number of defects following exponential-law dependence and reaching few 100 already at fractal iteration four. This work demonstrates a route for generation of fractal topological defect states in responsive soft matter. PMID:28117325

  9. Colloidal capsules: nano- and microcapsules with colloidal particle shells.

    Science.gov (United States)

    Bollhorst, Tobias; Rezwan, Kurosch; Maas, Michael

    2017-04-18

    Utilizing colloidal particles for the assembly of the shell of nano- and microcapsules holds great promise for the tailor-made design of new functional materials. Increasing research efforts are devoted to the synthesis of such colloidal capsules, by which the integration of modular building blocks with distinct physical, chemical, or morphological characteristics in a capsule's shell can result in novel properties, not present in previous encapsulation structures. This review will provide a comprehensive overview of the synthesis strategies and the progress made so far of bringing nano- and microcapsules with shells of densely packed colloidal particles closer to application in fields such as chemical engineering, materials science, or pharmaceutical and life science. The synthesis routes are categorized into the four major themes for colloidal capsule formation, i.e. the Pickering-emulsion based formation of colloidal capsules, the colloidal particle deposition on (sacrificial) templates, the amphiphilicity driven self-assembly of nanoparticle vesicles from polymer-grafted colloids, and the closely related field of nanoparticle membrane-loading of liposomes and polymersomes. The varying fields of colloidal capsule research are then further categorized and discussed for micro- and nano-scaled structures. Finally, a special section is dedicated to colloidal capsules for biological applications, as a diverse range of reports from this field aim at pharmaceutical agent encapsulation, targeted drug-delivery, and theranostics.

  10. Patterned Colloidal Photonic Crystals.

    Science.gov (United States)

    Hou, Jue; Li, Mingzhu; Song, Yanlin

    2018-03-01

    Colloidal photonic crystals (PCs) have been well developed because they are easy to prepare, cost-effective, and versatile with regards to modification and functionalization. Patterned colloidal PCs contribute a novel approach to constructing high-performance PC devices with unique structures and specific functions. In this review, an overview of the strategies for fabricating patterned colloidal PCs, including patterned substrate-induced assembly, inkjet printing, and selective immobilization and modification, is presented. The advantages of patterned PC devices are also discussed in detail, for example, improved detection sensitivity and response speed of the sensors, control over the flow direction and wicking rate of microfluidic channels, recognition of cross-reactive molecules through an array-patterned microchip, fabrication of display devices with tunable patterns, well-arranged RGB units, and wide viewing-angles, and the ability to construct anti-counterfeiting devices with different security strategies. Finally, the perspective of future developments and challenges is presented. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Flocking ferromagnetic colloids.

    Science.gov (United States)

    Kaiser, Andreas; Snezhko, Alexey; Aranson, Igor S

    2017-02-01

    Assemblages of microscopic colloidal particles exhibit fascinating collective motion when energized by electric or magnetic fields. The behaviors range from coherent vortical motion to phase separation and dynamic self-assembly. Although colloidal systems are relatively simple, understanding their collective response, especially under out-of-equilibrium conditions, remains elusive. We report on the emergence of flocking and global rotation in the system of rolling ferromagnetic microparticles energized by a vertical alternating magnetic field. By combing experiments and discrete particle simulations, we have identified primary physical mechanisms, leading to the emergence of large-scale collective motion: spontaneous symmetry breaking of the clockwise/counterclockwise particle rotation, collisional alignment of particle velocities, and random particle reorientations due to shape imperfections. We have also shown that hydrodynamic interactions between the particles do not have a qualitative effect on the collective dynamics. Our findings shed light on the onset of spatial and temporal coherence in a large class of active systems, both synthetic (colloids, swarms of robots, and biopolymers) and living (suspensions of bacteria, cell colonies, and bird flocks).

  12. Colloid migration in fractured media

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, J.R. (California Univ., Berkeley, CA (USA). Dept. of Civil Engineering)

    1989-09-15

    Field studies at the Nevada Test Site by researchers at Lawrence Livermore National Laboratory have demonstrated that radionuclides are being transported by colloidal material suspended in groundwater. This observation is counter to most predictions from contaminant transport models because the models assume adsorbed species are immobile. The purpose of this research is to quantify the transport processes for colloidal materials and develop the mechanistic understanding necessary to predict radionuclide transport in fractured media. There were three areas of investigation during this year that have addressed these issues: chemical control of colloid deposition on clean mineral surfaces, colloid accumulation on fracture surfaces, and the influence of deposited colloids on colloid and tracer migration. 7 refs.

  13. SURFACE MODIFICATION OF NANOPARTICLES TO OPPOSE UPTAKE BY THE MONONUCLEAR PHAGOCYTE SYSTEM

    NARCIS (Netherlands)

    STORM, G; BELLIOT, SO; DAEMEN, T; LASIC, DD

    1995-01-01

    An overview of recent advances in the surface modification of colloidal particles to oppose uptake by the mononuclear phagocyte system (MPS) is presented. First, we describe the colloidal particles and hydrophilic coating materials investigated, with particular focus on the literature concerning

  14. Sonographic Determination of Spleen to Left Kidney Ratio among ...

    African Journals Online (AJOL)

    The weight and height of the subjects were obtained with the participants wearing light weight street clothes without shoes. Results: Measurement of spleen and left kidney lengths were reliable within and between sonographers. The spleen and left kidney lengths were not statistically different in boys and girls (p > 0.05).

  15. Wandering spleen: Case report | Mwango | East African Medical ...

    African Journals Online (AJOL)

    Wandering spleens are rare clinical entities found more commonly in women aged 20-40 years. We report one such case found in a 24-year-old nulliparous woman who presented with low abdominal pains of sudden onset and splenomegaly. An emergency abdominal CT scan showed an enlarged spleen located in the ...

  16. Evolution of the CT imaging findings of accessory spleen infarction

    International Nuclear Information System (INIS)

    Mendi, Resham; Abramson, Lisa P.; Pillai, Srikumar B.; Rigsby, Cynthia K.

    2006-01-01

    We report the case of a 12-year-old girl presenting with multiple episodes of left upper-quadrant pain caused by torsion of an accessory spleen. We present the CT findings of progression of accessory spleen infarction over the course of 7 days. (orig.)

  17. A wandering spleen presenting as a hypogastric mass: case report

    African Journals Online (AJOL)

    raoul

    2012-02-21

    Feb 21, 2012 ... Misawa T, Yoshida K, Shiba H, Kobayashi S, Yanaga K. Wandering spleen with chronic torsion. Am J Surg. 2008 Apr;195(4):504-5. This article on PubMed. 7. Fiquet-Francois C, Belouadah M, Ludot H, Defauw B. Wandering spleen in children: multicenter retrospective study. J Pediatr Surg. 2010.

  18. The wandering spleen: CT findings and possible pitfalls in diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Ben Ely, A.; Zissin, R.; Copel, L.; Vasserman, M.; Hertz, M.; Gottlieb, P.; Gayer, G

    2006-11-15

    Aim: To report the CT features of wandering spleen, a rare condition which can be incidentally detected as an abdominal or pelvic mass or can present with torsion, causing an acute abdomen. Materials and methods: The CT studies of seven patients, two children and five adults, with wandering spleen were reviewed. CT was performed urgently in three patients for acute abdomen, and electively in four. Results: CT findings of wandering spleen included absence of the spleen in its normal position and a mass located elsewhere in the abdomen or pelvis, i.e. an ectopic spleen, enhancing homogeneously in four cases and failing partially or completely to enhance in the other three, indicating infarction. A 'whirl' appearance representing the twisted splenic pedicle was seen in the three cases with torsion. Urgent splenectomy confirmed infarction secondary to torsion. Conclusion: The possible diagnosis of wandering spleen should be kept in mind when CT shows the spleen to be absent from its usual position and a mass is found elsewhere in the abdomen or pelvis. When, in addition, a 'whirl' or partial or no enhancement of this mass are seen in a case presenting with acute abdomen, torsion of a wandering spleen is a likely diagnosis.

  19. A true ectopic, locally vascularized spleen: a very rare anomaly.

    Science.gov (United States)

    Darius, T; Tollens, T; Aelvoet, Chr; Vanrykel, J P

    2009-01-01

    In contrast to a wandering or ectopic spleen which is vascularized by the original splenic vessels this case describes a true ectopic, locally vascularized spleen in the pelvis. To our knowledge this anomaly has never been described in the literature before.

  20. THE RESPONSE OF DISSEMINATED RETICULUM CELL SARCOMA TO THE INTRAVENOUS INJECTION OF COLLOIDAL RADIOACTIVE GOLD

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, Philip; Levitt, Seymour H.

    1963-06-15

    Case histories of two patients treated with colloidal radiogold for diffuse reticulum cell sarcoma are presented. Further analysis of the method is suggested by the unusually long survival time of one of the patients. It was concluded that, although external radiotherapy remains the treatment of choice in localized reticulum cell sarcoma, intravenous colloidal radiogold may be a useful agent in lymphosarcomas with diffuse minute neoplastic liver and spleen involvements. Intravenous colloidal radiogold can produce bone marrow depression and thrombocytopenia which can lead to death. This factor tends to argue against therapeutic use of the agent. It is suggested that no more than 50 mC Au/sup 198/ intravenously should be used for treatment of this disease. (R.M.G.)

  1. Polymers and colloids

    Energy Technology Data Exchange (ETDEWEB)

    Schurtenberger, P. [ETH Zurich, Inst. fuer Polymere, Zurich (Switzerland)

    1996-11-01

    A wealth of structural information from colloid and polymer solutions on a large range of length scales can be obtained using small angle neutron scattering (SANS) experiments. After a general introduction to the field of soft condensed matter, I shall give a few selected examples on how SANS combined with suitable contrast variation schemes can be used to extract information on the size and conformation of polymer coils in solution and in the melt, and on the local structure and flexibility of polymerlike micelles and microemulsions. (author) 8 figs., tabs., 44 refs.

  2. Neutron scattering from colloids

    International Nuclear Information System (INIS)

    Cebula, D.J.; Thomas, R.K.; Harris, N.M.; Tabony, J.; White, J.W.

    1978-01-01

    This paper appraises the usefulness of neutron diffraction and small angle scattering for determining the structure of dilute and concentrated sols. For monodisperse polystyrene latex, the particle size and density can be readily determined and an upper limit to density fluctuations within the colloid particle set. For the polystyrene latex peptized by the adsorption of laurate, the physical dimensions and packing density of the adsorbed phase can be determined. The effects of polydispersity for unpeptized and peptized graphite sols, and the effects of extreme particle anisotropy using sols of montmorillonite clay minerals have been studied. (author)

  3. Nematic Liquid-Crystal Colloids

    Science.gov (United States)

    Muševič, Igor

    2017-01-01

    This article provides a concise review of a new state of colloidal matter called nematic liquid-crystal colloids. These colloids are obtained by dispersing microparticles of different shapes in a nematic liquid crystal that acts as a solvent for the dispersed particles. The microparticles induce a local deformation of the liquid crystal, which then generates topological defects and long-range forces between the neighboring particles. The colloidal forces in nematic colloids are much stronger than the forces in ordinary colloids in isotropic solvents, exceeding thousands of kBT per micrometer-sized particle. Of special interest are the topological defects in nematic colloids, which appear in many fascinating forms, such as singular points, closed loops, multitudes of interlinked and knotted loops or soliton-like structures. The richness of the topological phenomena and the possibility to design and control topological defects with laser tweezers make colloids in nematic liquid crystals an excellent playground for testing the basic theorems of topology. PMID:29295574

  4. Nematic Liquid-Crystal Colloids

    Directory of Open Access Journals (Sweden)

    Igor Muševič

    2017-12-01

    Full Text Available This article provides a concise review of a new state of colloidal matter called nematic liquid-crystal colloids. These colloids are obtained by dispersing microparticles of different shapes in a nematic liquid crystal that acts as a solvent for the dispersed particles. The microparticles induce a local deformation of the liquid crystal, which then generates topological defects and long-range forces between the neighboring particles. The colloidal forces in nematic colloids are much stronger than the forces in ordinary colloids in isotropic solvents, exceeding thousands of kBT per micrometer-sized particle. Of special interest are the topological defects in nematic colloids, which appear in many fascinating forms, such as singular points, closed loops, multitudes of interlinked and knotted loops or soliton-like structures. The richness of the topological phenomena and the possibility to design and control topological defects with laser tweezers make colloids in nematic liquid crystals an excellent playground for testing the basic theorems of topology.

  5. Efficient uptake of blood-borne BK and JC polyomavirus-like particles in endothelial cells of liver sinusoids and renal vasa recta.

    Directory of Open Access Journals (Sweden)

    Jaione Simon-Santamaria

    Full Text Available Liver sinusoidal endothelial cells (LSECs are specialized scavenger cells that mediate high-capacity clearance of soluble waste macromolecules and colloid material, including blood-borne adenovirus. To explore if LSECs function as a sink for other viruses in blood, we studied the fate of virus-like particles (VLPs of two ubiquitous human DNA viruses, BK and JC polyomavirus, in mice. Like complete virions, VLPs specifically bind to receptors and enter cells, but unlike complete virions, they cannot replicate. 125I-labeled VLPs were used to assess blood decay, organ-, and hepatocellular distribution of ligand, and non-labeled VLPs to examine cellular uptake by immunohisto- and -cytochemistry. BK- and JC-VLPs rapidly distributed to liver, with lesser uptake in kidney and spleen. Liver uptake was predominantly in LSECs. Blood half-life (∼1 min, and tissue distribution of JC-VLPs and two JC-VLP-mutants (L55F and S269F that lack sialic acid binding affinity, were similar, indicating involvement of non-sialic acid receptors in cellular uptake. Liver uptake was not mediated by scavenger receptors. In spleen, the VLPs localized to the red pulp marginal zone reticuloendothelium, and in kidney to the endothelial lining of vasa recta segments, and the transitional epithelium of renal pelvis. Most VLP-positive vessels in renal medulla did not express PV-1/Meca 32, suggesting location to the non-fenestrated part of vasa recta. The endothelial cells of these vessels also efficiently endocytosed a scavenger receptor ligand, formaldehyde-denatured albumin, suggesting high endocytic activity compared to other renal endothelia. We conclude that LSECs very effectively cleared a large fraction of blood-borne BK- and JC-VLPs, indicating a central role of these cells in early removal of polyomavirus from the circulation. In addition, we report the novel finding that a subpopulation of endothelial cells in kidney, the main organ of polyomavirus persistence, showed

  6. The small spleen: sonographic patterns of functional hyposplenia or asplenia.

    Science.gov (United States)

    Görg, Christian; Eichkorn, Miriam; Zugmaier, Gerhard

    2003-01-01

    Functional hyposplenia or asplenia (FAS) can be associated with potential fatal infections. The diagnosis of FAS is traditionally made on liver-spleen scintigraphy and finding Howell-Jolly bodies within erythrocytes. In this retrospective study, our goal was to identify any characteristic sonographic findings of the spleen in patients with FAS in an attempt to determine whether the diagnosis of FAS can be made sonographically. In a review of all medical and sonographic records from the period of January 1, 1985, through December 31, 2001, we identified 24 patients (11 men, 13 women) in whom FAS had been diagnosed by liver-spleen scintigraphy (n = 13) or the finding of Howell-Jolly bodies (n = 11). The following sonographic parameters were determined: size of spleen (small, normal, or large), echotexture of the spleen (homogeneous versus inhomogeneous), echogenicity (isoechoic versus hyperechoic), presence of focal splenic lesions, and patterns of splenic vascularization as determined by color Doppler sonography (absent flow, hilar flow, or parenchymal flow). The spleen was small in 20 patients (83%) and normal in the other 4 (17%). Echotexture was homogeneous in 13 patients (54%) and inhomogeneous in 11 (46%). The spleen was isoechoic in 18 cases (75%) and hyperechoic in 6 (25%). Six patients (25%) had focal lesions. Color Doppler sonography showed absent flow in 4 patients (17%), hilar flow in 17 (71%), and hilar and parenchymal vascularization in 3 (12%). Sonographic findings in the spleen of patients with FAS are characterized predominantly by a small spleen with absence of parenchymal vascularization on color Doppler sonography in most cases. Future prospective studies will be necessary to confirm these findings and to determine whether FAS can be diagnosed reliably with sonography. Copyright 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:152-155, 2003

  7. Shear mechanical properties of the spleen: experiment and analytical modelling.

    Science.gov (United States)

    Nicolle, S; Noguer, L; Palierne, J-F

    2012-05-01

    This paper aims at providing the first shear mechanical properties of spleen tissue. Rheometric tests on porcine splenic tissues were performed in the linear and nonlinear regime, revealing a weak frequency dependence of the dynamic moduli in linear regime and a distinct strain-hardening effect in nonlinear regime. These behaviours are typical of soft tissues such as kidney and liver, with however a less pronounced strain-hardening for the spleen. An analytical model based on power laws is then proposed to describe the general shear viscoelastic behaviour of the spleen. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. [Objective assessment of trauma severity in patients with spleen injuries].

    Science.gov (United States)

    Alekseev, V S; Ivanov, V A; Alekseev, S V; Vaniukov, V P

    2013-01-01

    The work presents an analysis of condition severity of 139 casualties with isolated and combined spleen injuries on admission to a surgical hospital. The assessment of condition severity was made using the traditional gradation and score scale VPH-SP. The degree of the severity of combined trauma of the spleen was determined by the scales ISS. The investigation showed that the scale ISS and VPH-SP allowed objective measurement of the condition severity of patients with spleen trauma. The score assessment facilitated early detection of the severe category of the patients, determined the diagnostic algorithm and the well-timed medical aid.

  9. Accessory spleen compromising response to splenectomy for idiopathic thrombocytopenic purpura

    International Nuclear Information System (INIS)

    Ambriz, P.; Munoz, R.; Quintanar, E.; Sigler, L.; Aviles, A.; Pizzuto, J.

    1985-01-01

    Accessory spleens were sought in 28 patients who had undergone splenectomy for chronic idiopathic thrombocytopenic purpura (ITP), using a variety of techniques. Abdominal scintigraphy with autologous erythrocytes labeled with Tc-99m and opsonized with anit-D IgG (radioimmune method) proved to be most useful, clearly demonstrating one or more accessory spleens in 12 cases (43%). Computed tomography (CT) was also helpful. Four out of five patients demonstrated an increased platelet count following surgery, the effectiveness of which was illustrated by the radioimmune scan. Patients who have had splenectomy for chronic ITP should be scanned using radioimmune techniques and CT to determine whether an accessory spleen is present

  10. Microrheology of colloidal systems

    International Nuclear Information System (INIS)

    Puertas, A M; Voigtmann, T

    2014-01-01

    Microrheology was proposed almost twenty years ago as a technique to obtain rheological properties in soft matter from the microscopic motion of colloidal tracers used as probes, either freely diffusing in the host medium, or subjected to external forces. The former case is known as passive microrheology, and is based on generalizations of the Stokes–Einstein relation between the friction experienced by the probe and the host-fluid viscosity. The latter is termed active microrheology, and extends the measurement of the friction coefficient to the nonlinear-response regime of strongly driven probes. In this review article, we discuss theoretical models available in the literature for both passive and active microrheology, focusing on the case of single-probe motion in model colloidal host media. A brief overview of the theory of passive microrheology is given, starting from the work of Mason and Weitz. Further developments include refined models of the host suspension beyond that of a Newtonian-fluid continuum, and the investigation of probe-size effects. Active microrheology is described starting from microscopic equations of motion for the whole system including both the host-fluid particles and the tracer; the many-body Smoluchowski equation for the case of colloidal suspensions. At low fluid densities, this can be simplified to a two-particle equation that allows the calculation of the friction coefficient with the input of the density distribution around the tracer, as shown by Brady and coworkers. The results need to be upscaled to agree with simulations at moderate density, in both the case of pulling the tracer with a constant force or dragging it at a constant velocity. The full many-particle equation has been tackled by Fuchs and coworkers, using a mode-coupling approximation and the scheme of integration through transients, valid at high densities. A localization transition is predicted for a probe embedded in a glass-forming host suspension. The

  11. Gastric volvulus associated with wandering spleen in adult: Case report

    Directory of Open Access Journals (Sweden)

    Oktay Büyükaşık

    2012-07-01

    Full Text Available Gastric volvulus associated with wandering spleen is a rare diagnosis in adult ages. So far, only two cases have been reported in the literature. 82 year old male patients admitted to emergency department with complaint of nausea, vomiting and constipation. Physical examination and computerize tomography detected a big solid mass with regular contour which is full filling abdominal left lower quadrant. Exploratory laparotomy revealed a wandering spleen in sizes of 13x13x15 cm in the mentioned region. The spleen which had two masses on was partially ischemic. The stomach had rotated through cardiopyloric axis due to long pedicle of the spleen and adhesions neighborhood to corpoantral junction. Thus gastric passage was partialy obstructed. Splenectomy and anterior gastropexy were applied. The patient was discharged in health at 6th day postoperatively.

  12. Torsion of a Wandering Spleen Presenting as Acute Abdomen

    International Nuclear Information System (INIS)

    Chauhan, Narvir Singh; Kumar, Satish

    2016-01-01

    Wandering spleen is a rare condition which if uncorrected, can result in torsion and infarction. Clinical presentation of a wandering spleen can vary from asymptomatic abdominal mass to acute abdominal pain. Radiological investigations play a pivotal role in diagnosis as the clinical diagnosis is usually impossible. We present a case of wandering spleen with torsion and complete infarction that occurred in a 32-year-old multiparous female. The diagnosis was established preoperatively on colour Doppler and CT of the abdomen with subsequent confirmation on surgery. Wandering spleen is a rare clinical condition which can present as acute abdomen. An increased awareness of this entity together with the timely use of ultrasound and CT of the abdomen can play an important role in preoperative diagnosis and surgical management

  13. RNA Sequence of Spleen of Newcastle Disease Infected Chickens

    Data.gov (United States)

    US Agency for International Development — At 21 days of age, chickens were infected with Newcastle Disease virus (or a mock injection as controls), and spleens were harvested at 2 and 6 days post infection....

  14. Torsion of a wandering spleen | Carapinha | South African Journal of ...

    African Journals Online (AJOL)

    Abstract. Torsion of a wandering spleen is a rare and difficult diagnosis in the paediatric population, with death a possible outcome. In this paper we present our experience of a single case and discuss the embryology and management thereof.

  15. Liquid crystal boojum-colloids

    International Nuclear Information System (INIS)

    Tasinkevych, M; Silvestre, N M; Telo da Gama, M M

    2012-01-01

    Colloidal particles dispersed in a liquid crystal (LC) lead to distortions of the director field. The distortions are responsible for long-range effective colloidal interactions whose asymptotic behaviour is well understood. The short-distance behaviour depends on the structure and dynamics of the topological defects nucleated near the colloidal particles and a full nonlinear theory is required to describe it. Spherical colloidal particles with strong planar degenerate anchoring nucleate a pair of antipodal surface topological defects, known as boojums. We use the Landau-de Gennes theory to resolve the mesoscopic structure of the boojum cores and to determine the pairwise colloidal interactions. We compare the results in three (3D) and two (2D) spatial dimensions for spherical and disc-like colloidal particles, respectively. The corresponding free energy functionals are minimized numerically using finite elements with adaptive meshes. Boojums are always point-like in 2D, but acquire a rather complex structure in 3D, which depends on the combination of the anchoring potential, the radius of the colloid, the temperature and the LC elastic anisotropy. We identify three types of defect cores in 3D that we call single, double and split-core boojums, and investigate the associated structural transitions. The split-core structure is favoured by low temperatures, strong anchoring and small twist to splay or bend ratios. For sufficiently strong anchoring potentials characterized by a well-defined uniaxial minimum, the split-core boojums are the only stable configuration. In the presence of two colloidal particles, we observe substantial re-arrangements of the inner defects in both 3D and 2D. These re-arrangements lead to qualitative changes in the force-distance profile when compared to the asymptotic quadrupole-quadrupole interaction. In line with the experimental results, the presence of the defects prevents coalescence of the colloidal particles in 2D, but not in 3D

  16. Autotransplantation of spleen tissue in children with mansonic schistosomiasis who underwent splenectomy: Evaluation of splenic residual functions

    Directory of Open Access Journals (Sweden)

    Brandt Carlos Teixeira

    1998-01-01

    Full Text Available Autotransplantation of spleen tissue is an attempt for maintenance of splenic functions when splenectomy is indicated in children. It minimizes the risks of overwhelming postsplenectomy infection and it has been done in children with severe portal hypertension due to hepatosplenic mansonic schistosomiasis that underwent splenectomy. The purposes of this investigation were to study the morphology of the residual splenic tissue; to evaluate the residual filtration function of this splenosis; and to assess the immune response to polyvalent pneumococcal vaccine of these patients. Twenty-three children with portal hypertension from mansonic schistosomiasis who underwent splenectomy, ligature of the left gastric vein, autotransplantation of spleen tissue into an omental pouch were evaluated for residual splenic parenchyma and functions. Tc-99m sulfur colloid liver-spleen scans were used for detection of splenic nodules. The search for Howell Jolly bodies were used for assessing the filtration function and Enzyme-linked immunosorbent assay was used for measuring the relative rise in titter of specific pneumococcal antibodies. Splenosis was evident in all children; however, in two there were less than five splenic nodules in the greater omentum, which was considered insufficient. Howell-Jolly bodies were found in the peripheral blood only in these two patients with less evident splenosis. The immune response was adequate in 15 patients; it was intermediate in 4 patients and inadequate in 4 patients. Autotransplantation of spleen tissue into an omental pouch is efficient in maintaining the filtration splenic function in more than 90% of the cases and the immune response to pneumococcal vaccination in approximately 65% of the children.

  17. Investigation of the human spleen by X-ray microanalysis

    International Nuclear Information System (INIS)

    Kopani, M.; Jakubovsky, J.; Polak, S.

    2001-01-01

    Qualitative and quantitative topographic analysis using X-ray fluorescence (XRF), X-ray powder diffraction (XRD) and scanning electron microscopy was performed in tissue samples of rat and human spleens. The presence of silico-aluminium and silico-calcareous particles of various sizes could be seen. The presence of the inorganic substances mentioned in the human red pulp cords is assumed to be a consequence of the purifying function of the spleen. (Authors)

  18. Colloid facilitated transport of lanthanides through discrete fractures in chalk

    Science.gov (United States)

    Tran, Emily; Klein Ben-David, Ofra; Teutsch, Nadya; Weisbrod, Noam

    2015-04-01

    Geological disposal of high-level radioactive waste is the internationally agreed-upon, long term solution for the disposal of long lived radionuclides and spent fuel. Eventually, corrosion of the waste canisters may lead to leakage of their hazardous contents, and the radionuclides can ultimately make their way into groundwater and pose a threat to the biosphere. Engineered bentonite barriers placed around nuclear waste repositories are generally considered sufficient to impede the transport of radionuclides from their storage location to the groundwater. However, colloidal-sized mobile bentonite particles eroding from these barriers have come under investigation as a potential transport vector for radionuclides sorbed to them. In addition, the presence of organic matter in groundwater has been shown to additionally facilitate the uptake of radionuclides by the clay colloids. This study aims to evaluate the transport behaviors of radionuclides in colloid-facilitated transport through a fractured chalk matrix and under geochemical conditions representative of the Negev desert, Israel. Lanthanides are considered an acceptable substitute to actinides for research on radionuclide transportation due to their similar chemical behavior. In this study, the migration of Ce both with and without colloidal particles was explored and compared to the migration of a conservative tracer (bromide). Tracer solutions containing known concentrations of Ce, bentonite colloids, humic acid and bromide were prepared in a matrix solution containing salt concentrations representative of that of the average rain water found in the Negev. These solutions were then injected into a flow system constructed around a naturally fractured chalk core. Samples were analyzed for Ce and Br using ICP-MS, and colloid concentrations were determined using spectrophotographic analysis. Breakthrough curves comparing the rates of transportation of each tracer were obtained, allowing for comparison of

  19. [Torsion of wandering spleen in a teenager: about a case].

    Science.gov (United States)

    Dème, Hamidou; Akpo, Léra Géraud; Fall, Seynabou; Badji, Nfally; Ka, Ibrahima; Guèye, Mohamadou Lamine; Touré, Mouhamed Hamine; Niang, El Hadj

    2016-01-01

    Wandering or migrating spleen is a rare anomaly which is usually described in children. Complications, which include pedicle torsion, are common and can be life-threatening. We report the case of a 17 year-old patient with a long past medical history of epigastric pain suffering from wandering spleen with chronic torsion of the pedicle. The clinical picture was marked by spontaneously painful epigastric mass, evolved over the past 48 hours. Abdominal ultrasound objectified heterogeneous hypertrophied ectopic spleen in epigastric position and a subcapsular hematoma. Doppler showed a torsion of splenic pedicle which was untwisted 2 turns and a small blood stream on the splenic artery. Abdominal CT scan with contrast injection showed a lack of parenchymal enhancement of large epigastric ectopic spleen and a subcapsular hematoma. The diagnosis of wandering spleen with chronic torsion of the pedicle complicated by necrosis and subcapsular hematoma was confirmed. The patient underwent splenectomy. The postoperative course was uneventful. We here discuss the contribution of ultrasound and CT scan in the diagnosis of wandering spleen with chronic torsion of the pedicle.

  20. An easy way to put the spleen into the bag.

    Science.gov (United States)

    Cakir, Murat; Tekin, Ahmet; Kartal, Adil; Tuncer, Fatma Betul

    2013-09-01

    Splenectomy is a therapeutic and diagnostic procedure used in a wide range of situations. Laparoscopic splenectomy has become the gold standard in some hematological diseases. The laparoscopically removed spleen is placed into a surgical bag, a step which is sometimes the most time-consuming part of the operation. To present the method that we employed in laparoscopic splenectomy to place the specimen into the bag and extract it in an easier and simpler way. The proximal part of the splenorenal ligament is left undivided in the size of one LigaSure cut length to use as a stalk while placing the spleen into the surgical bag. The bag is advanced from the inferior pole of the spleen toward the superior pole. Only keeping the bag open is sufficient to place the spleen into the bag. Recently, me started to put the spleen into the bag easily before cutting upper attachment of the spleen laparoscopically. So far we applied this procedure in more than eleven cases without complication. Splenectomy is now the gold standard in the treatment of hematologic diseases that are resistant to medical treatment or that are not amenable to medical treatment because of its complications. Through our experience, the method that we describe here easily overcomes one of the most unpleasant parts of laparoscopic splenectomy.

  1. Positron tomographic imaging of the liver: 68Ga iron hydroxide colloid

    International Nuclear Information System (INIS)

    Kumar, B.; Miller, T.R.; Siegel, B.A.; Mathias, C.J.; Markham, J.; Ehrhardt, G.J.; Welch, M.J.

    1981-01-01

    A new radiopharmaceutical, 68 Ga ion hydroxide colloid, for hepatic imaging by positron emission tomography was prepared from the eluate of a 68 Ge- 68 Ga solvent extraction generator. In rats, 84% of the administered dose of colloid localized in the liver and 4.6% accumulated in the spleen. Initial imaging studies in normal dogs showed close correspondence of the findings by positron tomography and transmission computed tomography. Emission tomography with 68 Ga-colloid was performed in 10 patients with hepatic metastases demonstrated by conventional 99mTc sulfur colloid scintigraphy. All focal defects noted on the conventional scintigrams were easily identified and generally were seen more clearly by positron tomography. In one patient, additional lesions not identified on the initial 99mTc sulfur colloid images were demonstrated. The positron tomographic images were compared with those obtained by transmission computed tomography in seven patients; the two studies showed comparable findings in five patients, whereas positron tomography more clearly showed multiple lesions in two. Our results suggest that positron emission tomography is a suitable technique for obtaining high contrast, cross-sectional images of large abdominal organs

  2. Sonographic determination of normal spleen size in an adult African population

    Energy Technology Data Exchange (ETDEWEB)

    Mustapha, Zainab; Tahir, Abdulrahman [Department of Radiology, University of Maiduguri Teaching Hospital, Maiduguri, Borno State (Nigeria); Tukur, Maisaratu [Department of Human Physiology, University of Maiduguri, Maiduguri, Borno State (Nigeria); Bukar, Mohammed [Department of Obstetrics and Gynaecology, University of Maiduguri Teaching Hospital, Maiduguri, Borno State (Nigeria); Lee, Wai-Kit, E-mail: leewk33@hotmail.co [Department of Medical Imaging, St. Vincent' s Hospital, University of Melbourne, 41 Victoria Parade, Fitzroy, Victoria 3065 (Australia)

    2010-07-15

    Objective: The purpose of this study was to determine the normal range of spleen size in an adult African population, and compare the findings to published data to determine any correlation with ethnicity. Materials and methods: Three hundred and seventy-four African adults without conditions that can affect the spleen or splenic abnormalities were evaluated with ultrasonography. Spleen length, width and thickness were measured and spleen volume calculated. Spleen size was correlated with age, gender, height, weight, and body mass index. Results: The mean spleen volume was 120 cm{sup 3}. Spleen volume correlated with spleen width (r = 0.85), thickness (r = 0.83) and length (r = 0.80). Men had a larger mean spleen volume than women. No correlation was found between spleen volume and age, weight, height, or body mass index. Conclusion: Mean spleen volume in African adults is smaller than data from Western sources, and cannot be explained by difference in body habitus.

  3. The effects of labetalol (AH 5158) on adrenergic transmission in the cat spleen.

    Science.gov (United States)

    Blakeley, A G; Summers, R J

    1977-01-01

    1. The competitive alpha- and beta-adrenoceptor blocking agent labetalol, in concentrations up to 10(-4) M, produced dose-dependent increases in transmitter overflow from the isolated blood perfused spleen of the cat following nerve stimulation at 10 and 30 Hz. 2. At concentrations above 10(-4) M labetol produced a pronounced decrease in transmitter overflow. 3. Labetalol (1.5 X 10(-4) M) increased the recovery of 3H label in the venous blood following the close-arterial infusion of [3H]-(-)-noradrenaline indicating that the drug inhibits uptake of the amine. 4. Both labetalol (3.8 X 10(-5) M) and piperoxan (7.4 X 10(-6) M) produced parallel shifts to the right of the dose-response curves to noradrenaline and oxymetazoline in isolated strips of cat splenic capsule. In this preparation both drugs acted as competitive postsynaptic alpha-adrenoceptor blocking agents. 5. Labetalol (3.3 X 10(-5) M) increased the transmitter overflow following stimulation of the splenic nerves with 200 impulses at 10 Hz. The overflow could be further increased by subsequent addition of piperoxan (7.2 X 10(-6 M). Piperoxan (5.7 X 10(-6) M) alone produced a marked increase in transmitter overflow which could be further increased by subsequent addition of desmethylimipramine (DMI; 3.2 X 10(-5) M). Cocaine (1.5 X 10(-5) M) or DMI (5.4 X 10(-5 M) produced a small increase in transmitter overflow which was not further increased by addition of labetalol (2.8 X 10(-5) M). 6. Labetalol produced a biphasic effect on the responses of the isolated blood perfused spleen of the cat to nerve stimulation. With low doses (up to 10(-4) M) vascular responses were potentiated and with high doses (greater than 10(-4) M) inhibited. The potentiation was related to uptake blockade and the inhibition to decreased transmitter overflow and postsynaptic alpha-adrenoceptor blockade. 7. Labetalol appears to act as a postsynaptic alpha-adrenoceptor antagonist in the isolated blood perfused spleen of the cat with

  4. Characterization of colloids in groundwater

    International Nuclear Information System (INIS)

    Kim, J.I.; Buckau, G.; Klenze, R.

    1987-07-01

    Natural colloids in the Gorleben aquifer systems have been investigated as for their chemical composition, quantification and size distribution. Humic substances appear to be the major organic materials in these groundwaters, generating humic colloids which are analysed to be humic acid (and fulvic acid) loaded with a large number of trace heavy metal ions. These metal ions include natural homologues of actinides and some fission products in trivalent, tetravalent and hexavalent state. Concentrations of trivalent and tetravalent heavy metal ions are linearly correlated with the dissolved organic carbon (DDC) concentration in different groundwaters. The DOC is found to be present as humic colloids. The Am 3+ ions introduced in such a groundwater readily undergo the generation of its pseudocolloids through sorption or ion exchange reactions with humic colloids. The chemical behaviour of Am(III), being similar to the trivalent metal ions, e.g. Fe 3+ , REE etc. found in natural colloids, has been investigated by laser induced photoacoustic spectroscopy (LPAS). Groundwaters from Ispra, Markham Clinton and Felslabor Grimsel. Bidistilled water and one of Gorleben groundwaters, Gohy 1011, are taken for the purpose of comparison. This groundwater contains the least amount of natural colloids of all Gorleben groundwaters hitherto investigated. An indirect quantification is made by comparison of the LPAS results with experiment from Latex solution. (orig./IRB)

  5. STAR-POLYMER -- COLLOID MIXTURES

    Directory of Open Access Journals (Sweden)

    J.Dzubiella

    2002-01-01

    Full Text Available Recent results in theory and simulation of star-polymer--colloid mixtures are reviewed. We present the effective interaction between hard, colloidal particles and star polymers in a good solvent derived by monomer-resolved Molecular Dynamics simulations and theoretical arguments. The relevant parameters are the size ratio q between the stars and the colloids, as well as the number of polymeric arms f (functionality attached to the common center of the star. By covering a wide range of q's ranging from zero (star against a flat wall up to about 0.5, we establish analytical forms for the star-colloid interaction which are in excellent agreement with simulation results. By employing this cross interaction and the effective interactions between stars and colloids themselves, a demixing transition in the fluid phase is observed and systematically investigated for different arm numbers and size ratios. The demixing binodals are compared with experimental observations and found to be consistent. Furthermore, we map the full two-component system on an effective one-component description for the colloids, by inverting the two-component Ornstein-Zernike equations. Some recent results for the depletion interaction and freezing transitions are shown.

  6. Colloid remediation in groundwater by polyelectrolyte capture

    International Nuclear Information System (INIS)

    Nuttall, H.E.; Rao, S.; Jain, R.

    1992-01-01

    This paper describes an ongoing study to characterize groundwater colloids, to understand the geochemical factors affecting colloid transport in groundwater, and to develop an in-situ colloid remediation process. The colloids and suspended particulate matter used in this study were collected from a perched aquifer site that has radiation levels several hundred times the natural background and where previous researchers have measured and reported the presence of radiocolloids containing plutonium and americium. At this site, radionuclides have spread over several kilometers. Inorganic colloids collected from water samples are characterized with respect to concentration, mineralogy, size distribution, electrophoretic mobility (zeta potential), and radioactivity levels. Presented are the methods used to investigate the physiochemical factors affecting colloid transport and the preliminary analytical results. Included below are a description of a colloid transport model and the corresponding computational code, water analyses, characterization of the inorganic colloids, and a conceptual description of a process for in-situ colloid remediation using the phenomenon of polyelectrolyte capture

  7. Microgels: Novel Colloidal Materials

    Directory of Open Access Journals (Sweden)

    Fernández-Nieves, A.

    2000-08-01

    Full Text Available Microgels are novel colloidal gels widely used because of the swelling or de-swelling exhibited under specific external conditions. In this work, the swelling and de-swelling of microgel particles is experimentally described. The medium pH, salt concentration and osmotic stress, are the three variables with which the change of phase has been realised. All transitions are found to occur well above the critical point of the system. Additionally, the basic applications in which the given transition is employed are described.

    Los microgeles son geles coloidales que se emplean por el inflado y/o desinflado que manifiestan ante ciertas condiciones externas. En este trabajo, se describe experimentalmente el inflado y el desinflado de partículas de gel. El pH del medio, su concentración iónica y el esfuerzo osmótico externo son las variables externas que se emplean para provocar el cambio de fase en las partículas. Todas las transiciones ocurren por encima del punto crítico del sistema. Adicionalmente, se presentan algunas de las aplicaciones en donde se emplea la transición provocada por la variable externa concreta.

  8. CT findings in children with blunt trauma in the spleen

    Energy Technology Data Exchange (ETDEWEB)

    Nishiguchi, Hiroyasu; Shimizu, Toshihisa; Ohmura, Makoto; Kawai, Naoki; Tauchi, Hayato; Hayakawa, Masao; Nishio, Yoshinori (Kyoto Second Red Cross Hospital (Japan)); Watanabe, Shinsuke

    1991-09-01

    We evaluated CT findings in 19 children with blunt injuries in the spleen. CT demonstrated laceration of the spleen in 7 children, rupture of the spleen in 7, and splenic hematoma in 5. Leakage of the contrast medium was observed in 3 children, of whom 1 was treated by arterial embolization. Laparotomy was performed in 3 children (15.8%) other than the 3 showing contrast medium leakage; hemostasis by compression was performed in 1 with laceration, and splenectomy in 2 with rupture. Late splenic rupture or abscess did not occur in any child. One child (5.3%) died of complicating injuries. Many of children with blunt splenic injuries can be successfully treated with conservative treatment, and CT scanning is useful for evaluating the degree of splenic injuries and complicating injuries. (author).

  9. Cancer of the colon spleen angle. Presentation of a case

    International Nuclear Information System (INIS)

    Martinez Sanchez, Yariana; De la Rosa Perez, Nereida; Barcelo Casanova, Renato E

    2010-01-01

    The colon cancer is currently an important public health problem in developed countries. It is the fourth most common cancer in the world. We report the case of a 65-years-old, black, female patient, assisting our consultation with dyspeptic disturbances as the unique symptom, without known risk factors. We indicated a colon by enema and a distal narrowing was observed at the colon spleen angle, at the same zone of the physiologic narrowing at that level. A colonoscopy was carried out diagnosing a left colon tumor near the spleen angle. It was operated with segmental resection of the spleen angle and a biopsy was made. Pathologic anatomy informed a well-differentiated colon adenocarcinoma

  10. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan and uptake uses ... the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is a ...

  11. Effect of ionizing radiation on cell death in frog spleen

    International Nuclear Information System (INIS)

    Afonin, V.Yu.; Vojtovich, A.M.

    1998-01-01

    It was studied the number of dead cells in frog spleen by means of coloration with trypan blue which allowed to estimate last stage of apoptosis dead of cells.The investigated frogs (Rana arvalis) were caught in september 1997 at radionuclide contamination territory (the Gomel Region, the Khojniki District). Control animals were caught in village Ratamka of the Minsk District. The percent of dead cells was less in control group in 1,5 times. Under additional irradiation (2 Gy) the number of dead cells in spleen also differs significantly in the investigated and control groups

  12. Spleen and liver enlargement in a patient with rheumatoid arthritis.

    Science.gov (United States)

    Bedoya, María Eugenia; Ceccato, Federico; Paira, Sergio

    2015-01-01

    We describe the case of a 51-year-old woman with a seropositive, erosive, and non-nodular rheumatoid arthritis of 15 year of evolution. The patient had poor compliance with medical visits and treatment. She came to the clinic with persistent pancytopenia and spleen and liver enlargement. Liver and bone marrow biopsies were carried out and amyloidosis, neoplasias and infections were ruled out. We discuss the differential diagnosis of pancytopenia and spleen and liver enlargement in a long-standing rheumatoid arthritis patient. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  13. Cystic lymphangioma of the spleen: US-CT-MRI correlation

    Energy Technology Data Exchange (ETDEWEB)

    Bezzi, M.; Spinelli, A.; Pierleoni, M.; Andreoli, G.M. [Dept. of Radiology, University of Rome ' La Sapienza' (Italy)

    2001-07-01

    A case of a surgically confirmed cystic lymphangioma of the spleen is presented. Preoperative imaging consisted of US, contrast-enhanced CT and MRI, all showing a multiloculated lesion with small cystic cavities divided by thin septa, corresponding to dilated lymphatic spaces. Preoperative studies correlated well with the pathologic findings. Cystic lymphangioma of the spleen is a very rare condition and is usually solitary and asymptomatic. Large lymphangiomas may be an indication for splenectomy, since the risk of rupture is high even from minor abdominal trauma. Preoperative diagnosis may be achieved with correlated noninvasive imaging. (orig.)

  14. The radiation chemistry of colloids

    International Nuclear Information System (INIS)

    Sellers, R.M.

    1976-08-01

    One of the most important problems associated with water cooled reactors is the accumulation on the pipework of radio-active deposits. These are formed from corrosion products which become activated during their passage through the reactor core. The first step of the activation process involves the deposition of the corrosion products, which are present as either colloidal or particulate matter, onto surfaces in the reactor core, i.e. within the radiation zone. A review of the literature on the effect of radiation on colloids is presented. Particular emphasis is given to the dependence of colloidal parameters such as particle size, turbidity and electrophoretic mobility on radiation dose. Most of the data available is of a qualitative nature only. Evidence is presented that colloids of iron are affected (in some cases precipitated) by radiation, and it is suggested that this process plays a part in the deposition of corrosion products in nuclear reactor cores. The bulk of the information available can be rationalized in terms of the radiation chemistry of aqueous solutions, and the interaction of the radicals produced with the atoms or molecules at the surface of the colloidal particles. This approach is very successful in explaining the variation of the mean particle size of monodisperse sulphur hydrosols with dose, for which quantitative experimental data are available. (author)

  15. Colloid Thrusters, Physics, Fabrication and Performance

    National Research Council Canada - National Science Library

    Martinez-Sanchez, Manuel; Akinwande, Akintunde I

    2005-01-01

    ... discovered pure ionic mode, the microfabrication in Silicon of two types of arrays of colloid or electrospray emitters, and the development of a quantitative theory for the colloidal regime (no ions...

  16. Crack formation and prevention in colloidal drops

    Science.gov (United States)

    Kim, Jin Young; Cho, Kun; Ryu, Seul-A.; Kim, So Youn; Weon, Byung Mook

    2015-08-01

    Crack formation is a frequent result of residual stress release from colloidal films made by the evaporation of colloidal droplets containing nanoparticles. Crack prevention is a significant task in industrial applications such as painting and inkjet printing with colloidal nanoparticles. Here, we illustrate how colloidal drops evaporate and how crack generation is dependent on the particle size and initial volume fraction, through direct visualization of the individual colloids with confocal laser microscopy. To prevent crack formation, we suggest use of a versatile method to control the colloid-polymer interactions by mixing a nonadsorbing polymer with the colloidal suspension, which is known to drive gelation of the particles with short-range attraction. Gelation-driven crack prevention is a feasible and simple method to obtain crack-free, uniform coatings through drying-mediated assembly of colloidal nanoparticles.

  17. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    Directory of Open Access Journals (Sweden)

    Guler Urcan

    2015-01-01

    Full Text Available Optical properties of colloidal plasmonic titanium nitride nanoparticles are examined with an eye on their photothermal and photocatalytic applications via transmission electron microscopy and optical transmittance measurements. Single crystal titanium nitride cubic nanoparticles with an average size of 50 nm, which was found to be the optimum size for cellular uptake with gold nanoparticles [1], exhibit plasmon resonance in the biological transparency window and demonstrate a high absorption efficiency. A self-passivating native oxide at the surface of the nanoparticles provides an additional degree of freedom for surface functionalization. The titanium oxide shell surrounding the plasmonic core can create new opportunities for photocatalytic applications.

  18. Colloid release from soil aggregates

    DEFF Research Database (Denmark)

    Vendelboe, Anders Lindblad; Møldrup, Per; Schjønning, Per

    2012-01-01

    The content of water-dispersible colloids (WDC) has a major impact on soil functions and structural stability. In addition, the presence of mobile colloids may increase the risk of colloid-facilitated transport of strongly sorbing environmental contaminants. The WDC content was measured in 39 soils......, using laser diffraction, by agitating the samples using a wet-dispersion unit. This approach eliminated the need for long sedimentation times required by the more classical end-over-end shaking approach and provided information about the time-dependent release of WDC. The total clay content of the soils...... ranged from 0.1 to 0.44 kg kg−1. The WDC content was measured on air-dry and moist 1- to 2-mm aggregates. The WDC content at a reference time was highly correlated to the total clay content (r > 0.91, P soils. Only for two sites was the WDC content correlated to the content of clay...

  19. Colloidal transport by active filaments.

    Science.gov (United States)

    Manna, Raj Kumar; Kumar, P B Sunil; Adhikari, R

    2017-01-14

    Enhanced colloidal transport beyond the limit imposed by diffusion is usually achieved through external fields. Here, we demonstrate the ballistic transport of a colloidal sphere using internal sources of energy provided by an attached active filament. The latter is modeled as a chain of chemo-mechanically active beads connected by potentials that enforce semi-flexibility and self-avoidance. The fluid flow produced by the active beads and the forces they mediate are explicitly taken into account in the overdamped equations of motion describing the colloid-filament assembly. The speed and efficiency of transport depend on the dynamical conformational states of the filament. We characterize these states using filament writhe as an order parameter and identify ones yielding maxima in speed and efficiency of transport. The transport mechanism reported here has a remarkable resemblance to the flagellar propulsion of microorganisms which suggests its utility in biomimetic systems.

  20. Colloidal transport by active filaments

    Science.gov (United States)

    Manna, Raj Kumar; Kumar, P. B. Sunil; Adhikari, R.

    2017-01-01

    Enhanced colloidal transport beyond the limit imposed by diffusion is usually achieved through external fields. Here, we demonstrate the ballistic transport of a colloidal sphere using internal sources of energy provided by an attached active filament. The latter is modeled as a chain of chemo-mechanically active beads connected by potentials that enforce semi-flexibility and self-avoidance. The fluid flow produced by the active beads and the forces they mediate are explicitly taken into account in the overdamped equations of motion describing the colloid-filament assembly. The speed and efficiency of transport depend on the dynamical conformational states of the filament. We characterize these states using filament writhe as an order parameter and identify ones yielding maxima in speed and efficiency of transport. The transport mechanism reported here has a remarkable resemblance to the flagellar propulsion of microorganisms which suggests its utility in biomimetic systems.

  1. COLLOID RELEASE FROM DIFFERENT SOIL DEPTH

    Directory of Open Access Journals (Sweden)

    Gang Chen

    2013-01-01

    Full Text Available Naturally occurring clay colloidal particles are heavily involved in sediment processes in the subsurface soil. Due to the import ance of these processes in the subsurface environment, the transport of clay colloidal particles has been studied in several disciplines, including soil sciences, petr ology, hydrology, etc. Specifically, in environmental engineering, clay colloid re lease and transport in the sediments have been extensively investigated, which are motiv ated by environmental concerns such as colloid-facilitated contaminant transport in groundwater and the subsurface soil. Clay colloid release is resulted from physical alteration of subsurface sediments. Despite the potential importance of clay colloid activiti es, the detailed mechanisms of release and transport of clay colloidal particles with in natural sediments are poorly understood. Pore medium structure, properties and flow dynamics, etc. are factors that affect clay colloid generation, mobilization, and subse quent transport. Possible mechanisms of clay colloid generation in the sediments in clude precipitation, erosion and mobilization by changes in pore water chemistry and clay colloid release depends on a balance of applied hydrodynamic and resisting adhesive torques and forces. The coupled role of pore water chemistry and fluid hydrodynamics thus play key roles in controlling clay colloid release and transport in the sediment s. This paper investigated clay colloidal particle release and transport, especially th e colloidal particle release mechanisms as well as the process modeling in the sediments. In this research, colloidal particle release from intact sediment columns with variable length was examined and colloidal particle release curves were simulated using an im plicit, finite-difference scheme. Colloidal particle release rate coefficient was found to be an exponential function of the sediment depth. The simulated results demonstrated that transport parameters were

  2. Reagent for making technetium-99m labelled tin colloid for body scanning

    International Nuclear Information System (INIS)

    Harrison, R.C.

    1984-01-01

    A packaged reagent for making Technetium-99m labelled tin colloids comprises 0.75 to 750 μg stannous tin, 50 to 7000 μg sodium. potassium or ammonium ion, 40 to 5000 μg fluoride ion, 50 to 10,000 μg of non-toxic non-ionic surface-active agent based on poly(alkylene oxide)glycol and a container aseptically enclosing said reagent. The presence of the surface-active agent, preferably one of the Pluronic types, results in smaller sized particles being produced on addition of pertechnetate to the reagent. This results in a higher liver/spleen biodistribution ratio

  3. Colloidal phytosterols: synthesis, characterization and bioaccessibility

    NARCIS (Netherlands)

    Rossi, L.; Seijen ten Hoorn, J.W.M.; Melnikov, S.M.; Velikov, K.P.

    2010-01-01

    We demonstrate the synthesis of phytosterol colloidal particles using a simple food grade method based on antisolvent precipitation in the presence of a non-ionic surfactant. The resulting colloidal particles have a rod-like shape with some degree of crystallinity. The colloidal dispersions display

  4. Self-Assembly of Faceted Colloidal Particles

    NARCIS (Netherlands)

    Gantapara, A.P.

    2015-01-01

    A colloidal dispersion consists of insoluble microscopic particles that are suspended in a solvent. Typically, a colloid is a particle for which at least one of its dimension is within the size range of a nanometer to a micron. Due to collisions with much smaller solvent molecules, colloids perform

  5. Colloid formation during waste glass corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Mertz, C.J.; Buck, E.C.; Fortner, J.A.; Bates, J.K.

    1996-05-01

    The long-term behavior of nuclear waste glass in a geologic repository may require a technical consideration of the role of colloids in the release and transport of radionuclides. The neglect of colloidal properties in assessing the near- and far-field migration behavior of actinides may lead to significant underestimates and poor predictions of biosphere exposure from high-level waste (HLW) disposal. Existing data on colloid-facilitated transport suggests that radionuclide migration may be enhanced, but the importance of colloids is not adequately assessed. Indeed, the occurrence of radionuclide transport, attributed to colloidal species, has been reported at Mortandad Canyon, Los Alamos and at the Nevada Test Site; both unsaturated regions are similar to the proposed HLW repository at Yucca Mountain. Although some developments have been made on understanding the transport characteristics of colloids, the characterization of colloids generated from the corrosion of the waste form has been limited. Colloids are known to incorporate radionuclides either from hydrolysis of dissolved species (real colloids) or from adsorption of dissolved species onto existing groundwater colloids (pseudocolloids); however, these colloids may be considered secondary and solubility limited when compared to the colloids generated during glass alteration.

  6. Sonographic biometry of spleen among school age children in ...

    African Journals Online (AJOL)

    EB

    among children population they studied. Thus the normal limits and percentile curves of the spleen among school age children were defined according to body weight in a Turkish population10. These differences with present study may be due to variations in race or different ethnic origins. There is no consensus on which.

  7. Histopathological study and audit of the spleen in Nigerians ...

    African Journals Online (AJOL)

    kemrilib

    underreporting both the gross and microscopic changes in the organ by pathologists. This paper therefore is a study on spleen specimens with a view to auditing the gross and microscopic description and analysing the pathological findings in splenectomy specimens with respect to gender and age. Materials and Methods.

  8. Sonographic assessment of the normal limits of the spleen in ...

    African Journals Online (AJOL)

    2013-12-14

    Dec 14, 2013 ... Tables 2 and 3 show a direct relationship of the spleen length with both age and body size indices. Table 3 shows a. Pearson correlation matrix of the splenic length with other variables. The splenic length correlated best with BSA, followed by WT. The splenic length was established to be longer in males.

  9. Differential expression of heparan sulfate domains in rat spleen.

    NARCIS (Netherlands)

    Dam, G.B. ten; Hafmans, T.G.M.; Veerkamp, J.H.; Kuppevelt, A.H.M.S.M. van

    2003-01-01

    The microarchitecture of the spleen is composed of a meshwork of reticulum cells and their matrix. Heparan sulfates (HS) are important components of this meshwork and are involved in processes such as cell adhesion, cell migration, and cytokine/growth factor binding. The expression of HS epitopes

  10. Morphology and some biomechanical properties of human liver and spleen

    Czech Academy of Sciences Publication Activity Database

    Stingl, J.; Bača, V.; Čech, V.; Kovanda, J.; Kovandová, H.; Mandys, Václav; Rejmontová, J.; Sosna, B.

    2002-01-01

    Roč. 24, - (2002), s. 285-289 ISSN 0930-1038 Institutional research plan: CEZ:AV0Z5039906 Keywords : Human liver and spleen Subject RIV: FE - Other Internal Medicine Disciplines Impact factor: 0.252, year: 2002

  11. Spleen Weight, Liver Weight And Levels Of Circulating Immune ...

    African Journals Online (AJOL)

    Three groups of mice viz: well fed mice, vitamin deficient mice and vitamin deficient Plasmodium berghei infected mice were studied. In these groups of mice, the weights of the liver and spleen were determined using a weighing balance and the levels of circulating immune complexes (CICS) measured ...

  12. Spontaneous rupture of the spleen after infectious mononucleosis

    DEFF Research Database (Denmark)

    Gulstad, Mikkel Bak; Thomsen, Henrik

    2013-01-01

    Non-traumatic rupture of the spleen (NRS) is a rare but serious complication to infectious mononucleosis (IM) and it is important to have in mind, when patients have IM. Although splenectomy has been advocated as the appropriate treatment for this problem, the trend goes towards conservative...

  13. Primary hemangiosarcoma of the spleen with angioscintigraphic demonstration of metastases

    DEFF Research Database (Denmark)

    Hermann, G G; Fogh, J; Graem, N

    1984-01-01

    A case of primary hemangiosarcoma of the spleen in a 48-year-old woman is presented. Twenty-eight months after splenectomy the patient developed a severe anemia of the microangiopathic type, thrombocytopenia, and a leukoerythroblastic peripheral blood picture. In contrast to x-ray and conventional...

  14. Sonographic Dimensions of the Spleen in Healthy School Age ...

    African Journals Online (AJOL)

    The spleen is the largest recticuloendothelial organ in the body which increases in size with several pathologies. Its average length and other dimensions have been documented in adults but none in children in our environment. This study is aimed at investigating with Ultrasonography the normal splenic dimensions in ...

  15. Bonding assembled colloids without loss of colloidal stability

    NARCIS (Netherlands)

    Vutukuri, H.R.; Stiefelhagen, J.C.P.; Vissers, T; Imhof, A.; van Blaaderen, A.

    2012-01-01

    In recent years the diversity of self-assembled colloidal structures has strongly increased, as it is fueled by a wide range of applications in materials science and also in soft condensed-matter physics.[1–4] Some potential applications include photonic bandgap (PBG) crystals, materials for

  16. Experimental studies on the inventory of cement-derived colloids in the pore water of a cementitious backfill material

    Energy Technology Data Exchange (ETDEWEB)

    Wieland, E

    2001-06-01

    experimental results of the study. Predictions of the colloidal effect on radionuclide mobility were based on the assumption that colloids dispersed in the pore water of the backfill material may reduce radionuclide sorption (R{sub d} values) on cement. This effect was described in terms of a sorption reduction factor. The distribution ratios (R{sub c}) of radionuclides between the cement pore water and the colloidal phase as well as the colloid mass concentration (m{sub c}) are the two important colloidal parameters affecting sorption reduction. No significant sorption reduction is expected for weakly and moderately sorbing radionuclides (R{sub d} {<=} 1 m{sup 3} kg{sup -1}) up to a colloid concentration of 1 ppm. Moreover, no significant sorption reduction is anticipated for strongly sorbing radionuclides (R{sub d} > 1 m{sup 3} kg{sup -1}) below colloid concentrations of 0.1 ppm. This value is considered to be representative for the backfill material. At higher colloid concentrations, however, sorption reduction may occur in case of the strongly sorbing radionuclides. Nevertheless, due to an extremely strong uptake of these elements by cement in the absence of colloids, the effective sorption values in the presence of colloids are predicted to be still high. (author)

  17. Depletion of spleen macrophages delays AA amyloid development: a study performed in the rapid mouse model of AA amyloidosis.

    Directory of Open Access Journals (Sweden)

    Katarzyna Lundmark

    Full Text Available AA amyloidosis is a systemic disease that develops secondary to chronic inflammatory diseases Macrophages are often found in the vicinity of amyloid deposits and considered to play a role in both formation and degradation of amyloid fibrils. In spleen reside at least three types of macrophages, red pulp macrophages (RPM, marginal zone macrophages (MZM, metallophilic marginal zone macrophages (MMZM. MMZM and MZM are located in the marginal zone and express a unique collection of scavenger receptors that are involved in the uptake of blood-born particles. The murine AA amyloid model that resembles the human form of the disease has been used to study amyloid effects on different macrophage populations. Amyloid was induced by intravenous injection of amyloid enhancing factor and subcutaneous injections of silver nitrate and macrophages were identified with specific antibodies. We show that MZMs are highly sensitive to amyloid and decrease in number progressively with increasing amyloid load. Total area of MMZMs is unaffected by amyloid but cells are activated and migrate into the white pulp. In a group of mice spleen macrophages were depleted by an intravenous injection of clodronate filled liposomes. Subsequent injections of AEF and silver nitrate showed a sustained amyloid development. RPMs that constitute the majority of macrophages in spleen, appear insensitive to amyloid and do not participate in amyloid formation.

  18. Nonspecific targeting of iron oxide nanoparticles to the liver, kidney and spleen: A novel approach to achieving specificity

    Science.gov (United States)

    Palihawadana Arachchige, Maheshika; Flack, Amanda; Chen, Xuequn; Li, Jing; Oupicky, David; Cheng, Y.-C. Norman; Shen, Yimin; Jena, Bhanu; Lawes, Gavin

    2013-03-01

    Recently, there has been significant interest in developing Fe3O4 nanoparticles for biomedical applications including targeted drug delivery and magnetic resonance imaging. One of the major problems in these applications is the undesirable filtration of these materials by the mononuclear phagocyte system. Preliminary magnetic resonance imaging and magnetization studies on hyaluronic acid coated nanoparticles injected intravenously into mice confirm that the nanoparticles accumulate in the liver, spleen, and kidneys. To identify whether certain specific proteins are responsible for nanoparticle accumulation in these organs, we exposed hyaluronic acid coated nanoparticles to proteins extracted from the liver, spleen, and kidneys, together with blood plasma proteins, then subsequently used gel electrophoresis and mass spectroscopy to identify the proteins binding to the nanoparticles. We find that the unwanted accumulation of nanoparticles in these organs can potentially be attributed to specific binding by a small number of proteins. By appropriately functionalizing the iron oxide nanoparticles, we expect that the nanoparticles uptake in the liver, spleen, and kidneys will be reduced.

  19. Colloid properties in groundwaters from crystalline formations

    International Nuclear Information System (INIS)

    Degueldre, C.A.

    1994-09-01

    Colloids are present in all groundwaters. The role they may play in the migration of safety-relevant radionuclides in the geosphere therefore must be studied. Colloid sampling and characterisation campaigns have been carried out in Switzerland. On the bases of the results from studies in the Grimsel area, Northern Switzerland and the Black Forest, as well as those obtained by other groups concerned with crystalline waters, a consistent picture is emerging. The groundwater colloids in crystalline formations are predominantly comprised of phyllosilicates and silica originating from the aquifer rock. Under constant hydrogeochemical conditions, the colloid concentration is not expected to exceed 100 ng.ml -1 when the calcium concentration is greater than 10 -4 . However, under transient chemical or physical conditions, such as geothermal or tectonic activity, colloid generation may be enhanced and the colloid concentration may reach 10 μg.ml -1 or more, if both the calcium and sodium concentrations are low. In the Nagra Crystalline Reference Water the expected colloid concentration is -1 . This can be compared, for example, to a colloid concentration of about 10 ng.ml -1 found in Zurzach water. The small colloid concentration in the reference water is a consequence of an attachment factor for clay colloids (monmorillonite) close to 1. A model indicates that at pH 8, the nuclide partition coefficients between water and colloid (K p ) must be smaller than 10 7 ml.g -1 if sorption takes place by surface complexation on colloids, = AIOH active groups forming the dominant sorption sites. This pragmatic model is based on the competition between the formation of nuclide hydroxo complexes in solution and their sorption on colloids. Experimental nuclide sorption data on colloids are compared with those obtained by applying this model. For a low colloid concentration, a sorption capacity of the order of 10 -9 M and reversible surface complexation, their presence in the

  20. Antigen Uptake during Different Life Stages of Zebrafish (Danio rerio) Using a GFP-Tagged Yersinia ruckeri

    DEFF Research Database (Denmark)

    Korbut, Rozalia; Mehrdana, Foojan; Kania, Per Walter

    2016-01-01

    was seen in the intestine 30 min pb and in the nares 2 hpb but never in scale pockets. Antigens were detected in the spleen 12 hpb. Zebrafish larvae exhibited major Yr uptake only in the mid-intestine enterocytes 24 hpb. The different life stages of zebrafish varied with regard to uptake locations, however...

  1. Colloid characterization and quantification in groundwater samples

    Energy Technology Data Exchange (ETDEWEB)

    K. Stephen Kung

    2000-06-01

    This report describes the work conducted at Los Alamos National Laboratory for studying the groundwater colloids for the Yucca Mountain Project in conjunction with the Hydrologic Resources Management Program (HRMP) and the Underground Test Area (UGTA) Project. Colloidal particle size distributions and total particle concentration in groundwater samples are quantified and characterized. Colloid materials from cavity waters collected near underground nuclear explosion sites by HRMP field sampling personnel at the Nevada Test Site (NTS) were quantified. Selected colloid samples were further characterized by electron microscope to evaluate the colloid shapes, elemental compositions, and mineral phases. The authors have evaluated the colloid size and concentration in the natural groundwater sample that was collected from the ER-20-5 well and stored in a 50-gallon (about 200-liter) barrel for several months. This groundwater sample was studied because HRMP personnel have identified trace levels of radionuclides in the water sample. Colloid results show that even though the water sample had filtered through a series of Millipore filters, high-colloid concentrations were identified in all unfiltered and filtered samples. They had studied the samples that were diluted with distilled water and found that diluted samples contained more colloids than the undiluted ones. These results imply that colloids are probably not stable during the storage conditions. Furthermore, results demonstrate that undesired colloids have been introduced into the samples during the storage, filtration, and dilution processes. They have evaluated possible sources of colloid contamination associated with sample collection, filtrating, storage, and analyses of natural groundwaters. The effects of container types and sample storage time on colloid size distribution and total concentration were studied to evaluate colloid stability by using J13 groundwater. The data suggests that groundwater samples

  2. Rare Case of an Epithelial Cyst in an Intrapancreatic Accessory Spleen Treated by Robot-Assisted Spleen Preserving Distal Pancreatectomy

    NARCIS (Netherlands)

    van Dijck, Willemijn P M; Groot, Vincent P; Brosens, Lodewijk A A; Hagendoorn, Jeroen; Rinkes, Inne H M Borel; van Leeuwen, Maarten S; Molenaar, I Quintus

    2016-01-01

    Epithelial cyst in an intrapancreatic accessory spleen (ECIPAS) is exceedingly rare with only 57 cases reported since the first publication in 1980. Comprehensive clinical and diagnostic features remain to be clarified. We present a case of ECIPAS in a 21-year-old Philippine woman who was admitted

  3. Inner Phases of Colloidal Hexagonal Spin Ice

    Science.gov (United States)

    Libál, A.; Nisoli, C.; Reichhardt, C. J. O.; Reichhardt, C.

    2018-01-01

    Using numerical simulations that mimic recent experiments on hexagonal colloidal ice, we show that colloidal hexagonal artificial spin ice exhibits an inner phase within its ice state that has not been observed previously. Under increasing colloid-colloid repulsion, the initially paramagnetic system crosses into a disordered ice regime, then forms a topologically charge ordered state with disordered colloids, and finally reaches a threefold degenerate, ordered ferromagnetic state. This is reminiscent of, yet distinct from, the inner phases of the magnetic kagome spin ice analog. The difference in the inner phases of the two systems is explained by their difference in energetics and frustration.

  4. A short textbook of colloid chemistry

    CERN Document Server

    Jirgensons, B

    1962-01-01

    A Short Textbook of Colloid Chemistry, Second Revised Edition details the factual aspect of colloid chemistry that includes the basic facts, established empirical and mathematical relationships, and practical applications. The chapters of the title are organized into two parts. In the first part, the text discusses the general concepts of colloid chemistry, such as the history and scope, basic terms, and basic methods in experiment with colloids. Part Two covers the technical aspect of colloid chemistry, such as the optical properties, electrical properties, and viscosity. The book will be of

  5. Microbial effects on colloidal agglomeration

    International Nuclear Information System (INIS)

    Hersman, L.

    1995-11-01

    Colloidal particles are known to enhance the transport of radioactive metals through soil and rock systems. This study was performed to determine if a soil microorganism, isolated from the surface samples collected at Yucca Mountain, NV, could affect the colloidal properties of day particles. The agglomeration of a Wyoming bentonite clay in a sterile uninoculated microbial growth medium was compared to the agglomeration in the medium inoculated with a Pseudomonas sp. In a second experiment, microorganisms were cultured in the succinate medium for 50 h and removed by centrifugation. The agglomeration of the clay in this spent was compared to sterile uninoculated medium. In both experiments, the agglomeration of the clay was greater than that of the sterile, uninoculated control. Based on these results, which indicate that this microorganism enhanced the agglomeration of the bentonite clay, it is possible to say that in the presence of microorganisms colloidal movement through a rock matrix could be reduced because of an overall increase in the size of colloidal particle agglomerates. 32 refs

  6. Colloidal aspects of texture perception

    NARCIS (Netherlands)

    Vliet, van T.

    2010-01-01

    The perception of complex textures in food is strongly related to the way food is processed during eating, and is modulated by other basic characteristics, such as taste and aroma. An understanding at the colloidal level of the basic processes in the mouth is essential in order to link the

  7. Characterization of Complex Colloidal Suspensions

    Science.gov (United States)

    Seaman, J. C.; Guerin, M.; Jackson, B. P.; Ranville, J. M.

    2003-04-01

    Surface chemical reactions play a major role in controlling contaminant fate and transport in the subsurface environment. Recent field and laboratory evidence suggests that mobile soil and groundwater colloids may facilitate the migration of sparingly soluble groundwater contaminants. Colloidal suspensions collected in the field or generated in laboratory column experiments tend to be fairly dilute in nature and comprised of relatively small particulates (reserved for studying ideal systems to the characterization of mobile colloids. However, many of these analytical techniques, including total/selective dissolution methods, dynamic light scattering, micro-electrophoresis, streaming potential, and even scanning electron microscopy (SEM), can be biased in of larger size fractions, and therefore, extremely sensitive to sampling, storage, and fractionation artifacts. In addition, surface modifiers such as sorbed oxides or organics can alter particulate appearance, composition, and behavior when compared to synthetic analogues or mineral standards. The current presentation will discuss the limitations and inherent biases associated with a number of analytical characterization techniques that are commonly applied to the study of mobile soil and groundwater colloids, including field flow fractionation (FFF) and acoustic based methods that have only recently become available.

  8. Improved transfection of spleen-derived antigen-presenting cells in culture using TATp-liposomes.

    Science.gov (United States)

    Pappalardo, Juan Sebastián; Quattrocchi, Valeria; Langellotti, Cecilia; Di Giacomo, Sebastián; Gnazzo, Victoria; Olivera, Valeria; Calamante, Gabriela; Zamorano, Patricia I; Levchenko, Tatyana S; Torchilin, Vladimir P

    2009-02-20

    Antigen presenting cells (APC) are among the most important cells of the immune system since they link the innate and the adaptative immune responses, directing the type of immune response to be elicited. To modulate the immune response in immune preventing or treating therapies, gene delivery into immunocompetent cells could be used. However, APC are very resistant to transfection. To increase the efficiency of APC transfection, we have used liposome-based lipoplexes additionally modified with cell-penetrating TAT peptide (TATp) for better intracellular delivery of a model plasmid encoding for the enhanced-green fluorescent protein (pEGFP). pEGFP-bearing lipoplexes made of a mixture of PC:Chol:DOTAP (60:30:10 molar ratio) with the addition of 2% mol of polyethylene glycol-phosphatidylethanolamine (PEG-PE) conjugate (plain-L) or TATp-PEG-PE (TATp-L) were shown to effectively protect the incorporated DNA from degradation. Uptake assays of rhodamine-labeled lipoplexes and transfections with the EGFP reporter gene were performed with APC derived from the mouse spleen. TATp-L-based lipoplexes allowed for significantly enhanced both, the uptake and transfection in APC. Such a tool could be used for the APC transfection as a first step in immune therapy.

  9. Glass/Jamming Transition in Colloidal Aggregation

    Science.gov (United States)

    Segre, Philip N.; Prasad, Vikram; Weitz, David A.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We have studied colloidal aggregation in a model colloid plus polymer system with short-range attractive interactions. By varying the colloid concentration and the strength of the attraction, we explored regions where the equilibrium phase is expected to consist of colloidal crystallites in coexistance with colloidal gas (i.e. monomers). This occurs for moderate values of the potential depth, U approximately equal to 2-5 kT. Crystallization was not always observed. Rather, over an extended sub-region two new metastable phases appear, one fluid-like and one solid-like. These were examined in detail with light scattering and microscopy techniques. Both phases consist of a near uniform distribution of small irregular shaped clusters of colloidal particles. The dynamical and structural characteristics of the ergodic-nonergodic transition between the two phases share much in common with the colloidal hard sphere glass transition.

  10. Purification technologies for colloidal nanocrystals.

    Science.gov (United States)

    Shen, Yi; Gee, Megan Y; Greytak, A B

    2017-01-10

    Almost all applications of colloidal nanocrystals require some type of purification or surface modification process following nanocrystal growth. Nanocrystal purification - the separation of nanocrystals from undesired solution components - can perturb the surface chemistry and thereby the physical properties of colloidal nanocrystals due to changes in solvent, solute concentrations, and exposure of the nanocrystal surface to oxidation or hydrolysis. For example, nanocrystal quantum dots frequently exhibit decreased photoluminescence brightness after precipitation from the growth solvent and subsequent redissolution. Consequently, purification is an integral part of the synthetic chemistry of colloidal nanocrystals, and the effect of purification methods must be considered in order to accurately compare and predict the behavior of otherwise similar nanocrystal samples. In this Feature Article we examine established and emerging approaches to the purification of colloidal nanoparticles from a nanocrystal surface chemistry viewpoint. Purification is generally achieved by exploiting differences in properties between the impurities and the nanoparticles. Three distinct properties are typically manipulated: polarity (relative solubility), electrophoretic mobility, and size. We discuss precipitation, extraction, electrophoretic methods, and size-based methods including ultracentrifugation, ultrafiltration, diafiltration, and size-exclusion chromatography. The susceptibility of quantum dots to changes in surface chemistry, with changes in photoluminescence decay associated with surface chemical changes, extends even into the case of core/shell structures. Accordingly, the goal of a more complete description of quantum dot surface chemistry has been a driver of innovation in colloidal nanocrystal purification methods. We specifically examine the effect of purification on surface chemistry and photoluminescence in quantum dots as an example of the challenges associated with

  11. Colloidal Photoluminescent Amorphous Porous Silicon, Methods Of Making Colloidal Photoluminescent Amorphous Porous Silicon, And Methods Of Using Colloidal Photoluminescent Amorphous Porous Silicon

    KAUST Repository

    Chaieb, Sahraoui

    2015-04-09

    Embodiments of the present disclosure provide for a colloidal photoluminescent amorphous porous silicon particle suspension, methods of making a colloidal photoluminescent amorphous porous silicon particle suspension, methods of using a colloidal photoluminescent amorphous porous silicon particle suspension, and the like.

  12. Primary Angiosarcoma of the Spleen: An Oncological Enigma

    Directory of Open Access Journals (Sweden)

    Myoteri Despoina

    2014-01-01

    Full Text Available Introduction. Primary splenic angiosarcoma is an extremely unusual neoplasm originating from sinusoidal vascular endothelium. Surgical extirpation is the mainstay of treatment of this highly malignant disease. Case Presentation. An 82-year-old woman was admitted with left pleural effusion and a palpable left upper quadrant abdominal mass, secondary to splenomegaly by two large splenic tumors. Classic open splenectomy was performed and angiosarcoma of the spleen was the final histopathological diagnosis, which was primary since no other disease site was revealed. Discussion. The incidence of the disease is 0.14–0.23 cases per million, with slight male predominance. Etiology is not established and clinical presentation may confuse even experienced physicians. Imaging modalities cannot differentiate the lesion from other vascular splenic neoplasms and the correct diagnosis is mainly set after histopathological examination of the resected spleen. As with other sarcomas, surgery is the only curative approach, while chemo- and radiotherapy have poor results. Prognosis remains dismal.

  13. Primary hemangiosarcoma of the spleen with angioscintigraphic demonstration of metastases

    DEFF Research Database (Denmark)

    Hermann, G G; Fogh, J; Graem, N

    1984-01-01

    A case of primary hemangiosarcoma of the spleen in a 48-year-old woman is presented. Twenty-eight months after splenectomy the patient developed a severe anemia of the microangiopathic type, thrombocytopenia, and a leukoerythroblastic peripheral blood picture. In contrast to x-ray and conventional...... of extremely vascular metastases. Autopsy 15 months later confirmed the scintigraphic findings. Angiography with 99mTc-labeled erythrocytes seems to be useful for monitoring metastases from hemangiosarcomas....

  14. Spleen necrosis virus, an avian retrovirus, can infect primate cells.

    OpenAIRE

    Koo, H M; Brown, A M; Ron, Y; Dougherty, J P

    1991-01-01

    Spleen necrosis virus (SNV) is an avian retrovirus that can infect some mammalian cells such as dog cells as well as all avian cells tested to date. We were interested in testing whether SNV could also infect primate cells. For these experiments, we used HeLa and COS-7 cells. Initially, we determined whether the SNV long terminal repeat promoter was functional in HeLa and COS-7 cells. In transient transfection assays, the SNV promoter efficiently directed chloramphenicol acetyltransferase gen...

  15. An easy way to put the spleen into the bag

    OpenAIRE

    Cakir, Murat; Tekin, Ahmet; Kartal, Adil; Tuncer, Fatma Betul

    2013-01-01

    Introduction Splenectomy is a therapeutic and diagnostic procedure used in a wide range of situations. Laparoscopic splenectomy has become the gold standard in some hematological diseases. The laparoscopically removed spleen is placed into a surgical bag, a step which is sometimes the most time-consuming part of the operation. Aim To present the method that we employed in laparoscopic splenectomy to place the specimen into the bag and extract it in an easier and simpler way. Material and meth...

  16. Pancreatitis-associated fluid collections involving the spleen

    International Nuclear Information System (INIS)

    Vick, C.W.; Simeone, J.F.; Ferrucci, J.T. Jr.; Wittenberg, J.; Mueller, P.R.; Harvard Medical School, Boston, MA

    1981-01-01

    The clinical and radiographic features of 2 patients with dissecting pancreatitis-associated fluid collections involving the spleen are described. A typical appearance of left upper quadrant fluid collection lateral to the splenic pulp was observed by ultrasonography (US) or computed body tomography (CBT). Although these findings are nonspecific, a left upper quadrant fluid collection may be characterized definitively by US/CBT-guided needle aspiration. (orig.)

  17. ALTERED HISTOLOGY OF THE THYMUS AND SPLEEN IN CONTAMINANT-EXPOSED JUVENILE AMERICAN ALLIGATORS

    Science.gov (United States)

    Morphological difference in spleen and thymus are closely related to functional immune differences. Hormonal regulation of the immune system has been demonstrated in reptilian splenic and thymic tissue. Spleens and thymus were obtained from juvenile alligators at two reference si...

  18. Comparative study on glucocerebrosidase in spleens from patients with Gaucher disease

    NARCIS (Netherlands)

    Aerts, J. M.; Donker-Koopman, W. E.; Brul, S.; van Weely, S.; Sa Miranda, M. C.; Barranger, J. A.; Tager, J. M.; Schram, A. W.

    1990-01-01

    In Gaucher disease (glucosylceramide lipidosis), deficiency of glucocerebrosidase causes pathological storage of glucosylceramide, particularly in the spleen. A comparative biochemical and immunological analysis has therefore been made of glucocerebrosidase in spleens from normal subjects (n = 4)

  19. Statistical Physics of Colloidal Dispersions.

    Science.gov (United States)

    Canessa, E.

    Available from UMI in association with The British Library. Requires signed TDF. This thesis is concerned with the equilibrium statistical mechanics of colloidal dispersions which represent useful model systems for the study of condensed matter physics; namely, charge stabilized colloidal dispersions and polymer stabilized colloidal dispersions. A one-component macroparticle approach is adopted in order to treat the macroscopic and microscopic properties of these systems in a simple and comprehensive manner. The thesis opens with the description of the nature of the colloidal state before reviewing some basic definitions and theory in Chapter II. In Chapter III a variational theory of phase equilibria based on the Gibbs-Bogolyobov inequality is applied to sterically stabilized colloidal dispersions. Hard spheres are chosen as the reference system for the disordered phases while an Einstein model is used for the ordered phases. The new choice of pair potential, taken for mathematical convenience, is a superposition of two Yukawa functions. By matching a double Yukawa potential to the van der Waals attractive potential at different temperatures and introducing a purely temperature dependent coefficient to the repulsive part, a rich variety of observed phase separation phenomena is qualitatively described. The behaviour of the potential is found to be consistent with a small decrease of the polymer layer thickness with increasing temperature. Using the same concept of a collapse transition the non-monotonic second virial coefficient is also explained and quantified. It is shown that a reduction of the effective macroparticle diameter with increasing temperature can only be partially examined from the point of view of a (binary-) polymer solution theory. This chapter concludes with the description of the observed, reversible, depletion flocculation behaviour. This is accomplished by using the variational formalism and by invoking the double Yukawa potential to allow

  20. Postnatal development of the spleen in Didelphis virginiana.

    Science.gov (United States)

    Cutts, J H; Krause, W J

    1982-01-01

    The postnatal development of the spleen has been examined in 85 opossums ranging in age from newborn to adult. At birth the spleen consists of a well vascularized mass of mesenchymal tissue and lacks lymphatic tissue or any evidence of haemopoietic activity. Haemopoiesis is evident at seven days, increases to a maximum at about two to three weeks and thereafter gradually declines. Although production of granulocytes has disappeared by 60 days postnatum, a small degree of erythropoiesis and megakaryocyte formation continues throughout life. Lymphatic tissue appears by the third week, but germinal centres do not appear until after weaning. A feature of the spleen during the first three to four days is the presence of a population of primitive 'blast' cells. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 18 Fig. 19 Fig. 20 Fig. 21 Fig. 22 Fig. 23 Fig. 24 PMID:7153176

  1. What happens when pharmaceuticals meet colloids.

    Science.gov (United States)

    Xing, Yingna; Chen, Xijuan; Zhuang, Jie; Chen, Xin

    2015-12-01

    Pharmaceuticals (PCs) have been widely detected in natural environment due to agricultural application of reclaimed water, sludge and animal wastes. Their potential risks to various ecosystems and even to human health have caused great concern; however, little was known about their environmental behaviors. Colloids (such as clays, metal oxides, and particulate organics) are kind of substances that are active and widespread in the environment. When PCs meet colloids, their interaction may influence the fate, transport, and toxicity of PCs. This review summarizes the progress of studies on the role of colloids in mediating the environmental behaviors of PCs. Synthesized results showed that colloids can adsorb PCs mainly through ion exchange, complexation and non-electrostatic interactions. During this process the structure of colloids and the stability of PCs may be changed. The adsorbed PCs may have higher risks to induce antibiotic resistance; besides, their transport may also be altered considering they have great chance to move with colloids. Solution conditions (such as pH, ionic strength, and cations) could influence these interactions between PCs and colloids, as they can change the forms of PCs and alter the primary forces between PCs and colloids in the solution. It could be concluded that PCs in natural soils could bind with colloids and then co-transport during the processes of irrigation, leaching, and erosion. Therefore, colloid-PC interactions need to be understood for risk assessment of PCs and the best management practices of various ecosystems (such as agricultural and wetland systems).

  2. THE COLLOIDAL BEHAVIOR OF EDESTIN

    Science.gov (United States)

    Hitchcock, David I.

    1922-01-01

    1. It has been shown by titration experiments that the globulin edestin behaves like an amphoteric electrolyte, reacting stoichiometrically with acids and bases. 2. The potential difference developed between a solution of edestin chloride or acetate separated by a collodion membrane from an acid solution free from protein was found to be influenced by salt concentration and hydrogen ion concentration in the way predicted by Donnan's theory of membrane equilibrium. 3. The osmotic pressure of such edestin-acid salt solutions was found to be influenced by salt concentration and by hydrogen ion concentration in the same way as is the potential difference. 4. The colloidal behavior of edestin is thus completely analogous to that observed by Loeb with gelatin, casein, and egg albumin, and may be explained by Loeb's theory of colloidal behavior, which is based on the idea that proteins react stoichiometrically as amphoteric electrolytes and on Donnan's theory of membrane equilibrium. PMID:19871959

  3. Improvement of colloid sampling techniques in groundwater and actinide characterisation of the groundwater systems at Gorleben (FRG) and El Berrocal (E)

    International Nuclear Information System (INIS)

    Dearlove, J.P.L.; Longworth, G.; Ivanovich, M.

    1990-08-01

    Two sites, the Gorleben site (FRG) and the El Berrocal Experimental station (E) have been studied to evaluate different sampling and analytical techniques for the characterisation of particulates (> 1000 nm size), colloids (1-1000 nm size) and the solution phase (<1 nm) in groundwaters in terms of their physical, chemical and actinide composition. The uptake characteristics of the field ultrafiltration system used to separate the colloid fraction from the solution phase in the groundwater have also been studied. (Author)

  4. Glass transition of soft colloids

    Science.gov (United States)

    Philippe, Adrian-Marie; Truzzolillo, Domenico; Galvan-Myoshi, Julian; Dieudonné-George, Philippe; Trappe, Véronique; Berthier, Ludovic; Cipelletti, Luca

    2018-04-01

    We explore the glassy dynamics of soft colloids using microgels and charged particles interacting by steric and screened Coulomb interactions, respectively. In the supercooled regime, the structural relaxation time τα of both systems grows steeply with volume fraction, reminiscent of the behavior of colloidal hard spheres. Computer simulations confirm that the growth of τα on approaching the glass transition is independent of particle softness. By contrast, softness becomes relevant at very large packing fractions when the system falls out of equilibrium. In this nonequilibrium regime, τα depends surprisingly weakly on packing fraction, and time correlation functions exhibit a compressed exponential decay consistent with stress-driven relaxation. The transition to this novel regime coincides with the onset of an anomalous decrease in local order with increasing density typical of ultrasoft systems. We propose that these peculiar dynamics results from the combination of the nonequilibrium aging dynamics expected in the glassy state and the tendency of colloids interacting through soft potentials to refluidize at high packing fractions.

  5. Preparation of radioactive colloidal gold 198Au

    International Nuclear Information System (INIS)

    Cammarosano, S.A.

    1979-01-01

    The preparation with simple equipment of radioactive colloidal gold of particle size about approximately 300 A from seed colloid stabilized by gelatine is described. Some physico-chemical parameters which can affect the process of formation of these colloidal particles are analysed; particle size has been meassured with an electron microscope. The colloid stability has been studied as a function of dilution, age and pH. Nucleation and growth of radioactive colloidal gold have been studied using spectrophotometry. Absorption spectra of the two ones are presented and compared. Quality control of the production process is verified through measurement of parameters, such as radioactive and radiochemical purity and biological distribution in laboratorial animals. This distribution was evalusted for rats injected endovenously with the gold colloidal solution.(Author) [pt

  6. Does colloid shape affect detachment of colloids by a moving air-water interface?

    Science.gov (United States)

    Aramrak, Surachet; Flury, Markus; Harsh, James B; Zollars, Richard L; Davis, Howard P

    2013-05-14

    Air-water interfaces interact strongly with colloidal particles by capillary forces. The magnitude of the interaction force depends on, among other things, the particle shape. Here, we investigate the effects of particle shape on colloid detachment by a moving air-water interface. We used hydrophilic polystyrene colloids with four different shapes (spheres, barrels, rods, and oblong disks), but otherwise identical surface properties. The nonspherical shapes were created by stretching spherical microspheres on a film of polyvinyl alcohol (PVA). The colloids were then deposited onto the inner surface of a glass channel. An air bubble was introduced into the channel and passed through, thereby generating a receding followed by an advancing air-water interface. The detachment of colloids by the air-water interfaces was visualized with a confocal microscope, quantified by image analysis, and analyzed statistically to determine significant differences. For all colloid shapes, the advancing air-water interface caused pronounced colloid detachment (>63%), whereas the receding interface was ineffective in colloid detachment (colloid shapes, the barrels were most readily removed (94%) by the advancing interface, followed by the spheres and oblong disks (80%) and the rods (63%). Colloid detachment was significantly affected by colloid shape. The presence of an edge, as it occurs in a barrel-shaped colloid, promoted colloid detachment because the air-water interface is being pinned at the edge of the colloid. This suggests that the magnitude of colloid mobilization and transport in porous media is underestimated for edged particles and overestimated for rodlike particles when a sphere is used as a model colloid.

  7. Colloid Titration--A Rapid Method for the Determination of Charged Colloid.

    Science.gov (United States)

    Ueno, Keihei; Kina, Ken'yu

    1985-01-01

    "Colloid titration" is a volumetric method for determining charged polyelectrolytes in aqueous solutions. The principle of colloid titration, reagents used in the procedure, methods of endpoint detection, preparation of reagent solutions, general procedure used, results obtained, and pH profile of colloid titration are considered. (JN)

  8. Colloidal paradigm in supercapattery electrode systems

    Science.gov (United States)

    Chen, Kunfeng; Xue, Dongfeng

    2018-01-01

    Among decades of development, electrochemical energy storage systems are now sorely in need of a new design paradigm at the nano size and ion level to satisfy the higher energy and power demands. In this review paper, we introduce a new colloidal electrode paradigm for supercapattery that integrates multiple-scale forms of matter, i.e. ion clusters, colloidal ions, and nanosized materials, into one colloid system, coupled with multiple interactions, i.e. electrostatic, van der Waals forces, and chemical bonding, thus leading to the formation of many redox reactive centers. This colloidal electrode not only keeps the original ionic nature in colloidal materials, but also creates a new attribute of high electroactivity. Colloidal supercapattery is a perfect application example of the novel colloidal electrode, leading to higher specific capacitance than traditional electrode materials. The high electroactivity of the colloidal electrode mainly comes from the contribution of exposed reactive centers, owing to the confinement effect of carbon and a binder matrix. Systematic and thorough research on the colloidal system will significantly promote the development of fundamental science and the progress of advanced energy storage technology.

  9. Conductivity maximum in a charged colloidal suspension

    Energy Technology Data Exchange (ETDEWEB)

    Bastea, S

    2009-01-27

    Molecular dynamics simulations of a charged colloidal suspension in the salt-free regime show that the system exhibits an electrical conductivity maximum as a function of colloid charge. We attribute this behavior to two main competing effects: colloid effective charge saturation due to counterion 'condensation' and diffusion slowdown due to the relaxation effect. In agreement with previous observations, we also find that the effective transported charge is larger than the one determined by the Stern layer and suggest that it corresponds to the boundary fluid layer at the surface of the colloidal particles.

  10. Nonequilibrium forces between dragged ultrasoft colloids.

    Science.gov (United States)

    Singh, Sunil P; Winkler, Roland G; Gompper, Gerhard

    2011-10-07

    The dynamical deformation of ultrasoft colloids as well as their dynamic frictional forces are numerically investigated, when one colloid is dragged past another at constant velocity. Hydrodynamic interactions are captured by a particle-based mesoscopic simulation method. At vanishing relative velocity, the equilibrium repulsive force-distance curve is obtained. At large drag velocities, in contrast, we find an apparent attractive force for departing colloids along the dragging direction. The deformation, in the close encounter of colloids, and the energy dissipation are examined as a function of the drag velocity and their separation.

  11. Contents of corticotropin-releasing hormone and arginine vasopressin immunoreativity in the spleen and thymus during a chronic inflammatory stress

    DEFF Research Database (Denmark)

    Chowdrey, H.S.; Lightman, S.L.; Harbuz, M.S.

    1994-01-01

    Corticotropin-releasing hormone, spleen, thymus, immune system, stress, arthritis, arginine vasopressin......Corticotropin-releasing hormone, spleen, thymus, immune system, stress, arthritis, arginine vasopressin...

  12. Segmentation of liver and spleen based on computational anatomy models.

    Science.gov (United States)

    Dong, Chunhua; Chen, Yen-Wei; Foruzan, Amir Hossein; Lin, Lanfen; Han, Xian-Hua; Tateyama, Tomoko; Wu, Xing; Xu, Gang; Jiang, Huiyan

    2015-12-01

    Accurate segmentation of abdominal organs is a key step in developing a computer-aided diagnosis (CAD) system. Probabilistic atlas based on human anatomical structure, used as a priori information in a Bayes framework, has been widely used for organ segmentation. How to register the probabilistic atlas to the patient volume is the main challenge. Additionally, there is the disadvantage that the conventional probabilistic atlas may cause a bias toward the specific patient study because of the single reference. Taking these into consideration, a template matching framework based on an iterative probabilistic atlas for liver and spleen segmentation is presented in this paper. First, a bounding box based on human anatomical localization, which refers to the statistical geometric location of the organ, is detected for the candidate organ. Then, the probabilistic atlas is used as a template to find the organ in this bounding box by using template matching technology. We applied our method to 60 datasets including normal and pathological cases. For the liver, the Dice/Tanimoto volume overlaps were 0.930/0.870, the root-mean-squared error (RMSE) was 2.906mm. For the spleen, quantification led to 0.922 Dice/0.857 Tanimoto overlaps, 1.992mm RMSE. The algorithm is robust in segmenting normal and abnormal spleens and livers, such as the presence of tumors and large morphological changes. Comparing our method with conventional and recently developed atlas-based methods, our results show an improvement in the segmentation accuracy for multi-organs (p<0.00001). Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Laparoscopic splenectomy for spontaneous rupture of the spleen

    Directory of Open Access Journals (Sweden)

    Pinky M Thapar

    2016-01-01

    Full Text Available Laparoscopic splenectomy is a gold standard for management of planned benign splenic pathologies. Spontaneous rupture of the spleen (SRS leading to acute abdomen occurs in only 1% of all splenic ruptures. Laparoscopic splenectomy in traumatic and atraumatic rupture due to intra-splenic pathology is reported. We present the first reported case of laparoscopic splenectomy in a 23-year-old male who presented with hemoperitoneum due to idiopathic or SRS. The procedure was safely accomplished with slight modified technique and minimum usage of advanced gadgets.

  14. Anatomical description of arterial segments of the spleen of deer.

    Science.gov (United States)

    Peres Ferraz de Melo, A; de Souza, W Machado; Rodrigues, R Felipe; Alves, F Ribeiro; Rici, R Eli Graci; Guerra, R Romão; Favaron, P Oliveira; Miglino, M Angélica; Di Dio, L John Aphonso

    2011-08-01

    With 2 figures The anatomosurgical segmentation of the arteries of the spleen was studied in 31 deer of the species Mazama gouazoubira and Blastocerus dichotomus by means of vascular injection with latex and vinyl acetate and radiographic examination. The arteria lienalis penetrated through the hilus lienis in 87% of the cases, whereas an extrahilar artery was present in the other cases. An extraparenchymal division of the lineal artery into two, three or four segmental arteries was observed in 74% of the cases. Anastomoses between intraparenchymal arterial branches were rare and of a reduced calibre. © 2011 Blackwell Verlag GmbH.

  15. Mucormycosis resulting in a pseudoaneurysm in the spleen

    Energy Technology Data Exchange (ETDEWEB)

    Nevitt, P.C.; Das Narla, L. [Medical College of Virginia, Virginia Commonwealth Univ., Richmond (United States); Hingsbergen, E.A. [Children' s Radiologic Institute, Children' s Hospital, Columbus, OH (United States)

    2001-02-01

    Mucormycosis is an uncommon and frequently fatal fungal infection. It characteristically affects patients with diabetes mellitus or patients with severe immunosuppression. The hallmark of mucormycosis infection is tissue infarction and vascular invasion. We present clinical data and imaging studies of a 16 year-old child with acute lymphoblastic leukemia complicated by disseminated mucormycosis resulting in a pseudoaneurysm of the spleen. This was successfully managed by a combination of systemic antifungal therapy (Amphotericin B) and surgery (splenectomy). This entity has not been described in the literature. (orig.)

  16. Serotonin uptake and serotonin uptake inhibition.

    Science.gov (United States)

    Fuller, R W; Wong, D T

    1990-01-01

    Serotonin uptake carriers occur on serotonin neurons, on glial cells and on blood platelets. The uptake carrier on serotonin neurons inactivates serotonin that has been released into the synaptic cleft by transporting it back into the nerve terminal. The serotonin uptake carrier is the means by which blood platelets acquire serotonin, since they do not synthesize it. The function of the serotonin uptake carrier on glial cells is poorly understood. Selective inhibitors of serotonin uptake enhance neurotransmission via serotonergic neurons and have been useful pharmacologic tools for studying physiologic roles of serotonin neurons. Some serotonin uptake inhibitors are finding therapeutic uses in mental depression and other psychiatric disorders and in treating obesity and bulimia; other therapeutic applications continue to be evaluated.

  17. Comparison of technetium-99m sulfur colloid and technetium-99m albumin colloid labeled solid meals for gastric emptying studies.

    Science.gov (United States)

    Taillefer, R; Douesnard, J M; Beauchamp, G; Guimond, J

    1987-08-01

    A Tc-99m albumin colloid (Tc-AC) kit has been introduced as an alternative to Tc-99m sulfur colloid (Tc-SC) for liver-spleen imaging. Since there is no need for boiling, the use of Tc-AC reduces preparation time and manipulation. Tc-SC is one of the most commonly used radiopharmaceuticals for the labeling of solid-phase markers in gastric emptying studies. In vitro studies were performed to evaluate the labeling efficiency and stability in hydrochloric acid and in human gastric juice of intracellularly labeled chicken liver and scrambled eggs labeled with Tc-SC and Tc-AC. Gastric emptying studies also were performed on 20 healthy volunteers with both Tc-SC and Tc-AC labeled scrambled egg sandwiches. There was no significant difference between Tc-SC and Tc-AC in the labeling efficiency of chicken liver (98% +/- 1% for Tc-SC, 96% +/- 2% for Tc-AC) and scrambled eggs (92% +/- 2% for Tc-SC, 91% +/- 3% for Tc-AC). However, both Tc-SC and Tc-AC labeled scrambled eggs showed a lower stability than chicken liver, particularly in human gastric juice. Gastric emptying curves from both meals in 20 normal subjects were also similar, with a mean half-emptying time of 85 +/- 13 minutes and 87 +/- 16 minutes for the meals containing Tc-SC and Tc-AC respectively. Tc-AC is a reliable alternative to Tc-SC as a radiotracer for solid-phase gastric emptying studies.

  18. Colloid transport in dual-permeability media.

    Science.gov (United States)

    Leij, Feike J; Bradford, Scott A

    2013-07-01

    It has been widely reported that colloids can travel faster and over longer distances in natural structured porous media than in uniform structureless media used in laboratory studies. The presence of preferential pathways for colloids in the subsurface environment is of concern because of the increased risks for disease caused by microorganisms and colloid-associated contaminants. This study presents a model for colloid transport in dual-permeability media that includes reversible and irreversible retention of colloids and first-order exchange between the aqueous phases of the two regions. The model may also be used to describe transport of other reactive solutes in dual-permeability media. Analytical solutions for colloid concentrations in aqueous and solid phases were obtained using Laplace transformation and matrix decomposition. The solutions proved convenient to assess the effect of model parameters on the colloid distribution. The analytical model was used to describe effluent concentrations for a bromide tracer and 3.2- or 1-μm-colloids that were observed after transport through a composite 10-cm long porous medium made up of a cylindrical lens or core of sand and a surrounding matrix with sand of a different grain size. The tracer data were described very well and realistic estimates were obtained for the pore-water velocity in the two flow domains. An accurate description was also achieved for most colloid breakthrough curves. Dispersivity and retention parameters were typically greater for the larger 3.2-μm-colloids while both reversible and irreversible retention rates tended to be higher for the finer sands than the coarser sand. The relatively small sample size and the complex flow pattern in the composite medium made it difficult to reach definitive conclusions regarding transport parameters for colloid transport. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Fabricating colloidal crystals and construction of ordered nanostructures

    Directory of Open Access Journals (Sweden)

    Sun Zhiqiang

    2006-01-01

    Full Text Available AbstractColloidal crystals of polymeric or inorganic microspheres are of extensive interest due to their potential applications in such as sensing, optics, photonic bandgap and surface patterning. The article highlights a set of approaches developed in our group, which are efficient to prepare colloidal crystals with ordered voids, patterned colloidal crystals on non-planar surfaces, heterogeneous colloidal crystals of different building blocks, colloidal crystals composed of non-spherical polyhedrons, and colloidal crystals of non-close-packed colloidal microspheres in particular. The use of these colloidal crystals as templates for different microstructures range from nanoscale to micron-scale is also summarized.

  20. Specific uptake of serotonin by murine lymphoid cells

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, J.C.; Walker, R.F.; Brooks, W.H.; Roszman, T.L.

    1986-03-01

    Recently the authors confirmed and extended earlier observations that serotonin (5-hydroxytryptamine, 5HT) can influence immune function. Both 5HT and its precursor, 5-hydroxytryptophan inhibit the primary, in vivo antibody response to sheep red blood cells, in mice. Here, the authors report specific in vitro association of this amine with mouse splenocytes. Spleen cells from 6-8 week old CBA/J mice incorporated /sup 3/H-5HT(10/sup -8/ to 2.5 x 10/sup -6/M) in a saturable manner, at 37/sup 0/C. Specificity of uptake was indicated by competition with excess (10/sup -5/M) unlabelled 5HT and with 10/sup -5/M fluoxetine, a selective inhibitor of active 5HT reuptake in rat brain. The 5HT receptor antagonists, methysergide and cyproheptadine, also blocked 5HT uptake. Cell lysis and displacement studies revealed largely intracellular accumulation of /sup 3/H-5HT with little membrane association, in splenocytes. Hofstee analysis of uptake kinetics yielded an apparent Km of 0.82 +/- 0.22 x 10/sup -7/M and Vmax of 501 +/- 108 pM/3 x 10/sup 6/ cells/10 min. Spleen cells fractionated on Sephadex G10 showed virtually no specific 5HT uptake while peritoneal exudate cells from thioglycollate treated mice displayed 5HT uptake kinetics similar to those of splenocytes. The site of specific /sup 3/H-5HT incorporation within a population of spleen cells and the functional significance of this phenomenon to immunomodulation by 5HT remain to be elucidated.

  1. Structural color from colloidal glasses

    Science.gov (United States)

    Magkiriadou, Sofia

    When a material has inhomogeneities at a lengthscale comparable to the wavelength of light, interference can give rise to structural colors: colors that originate from the interaction of the material's microstructure with light and do not require absorbing dyes. In this thesis we study a class of these materials, called photonic glasses, where the inhomogeneities form a dense and random arrangement. Photonic glasses have angle-independent structural colors that look like those of conventional dyes. However, when this work started, there was only a handful of colors accessible with photonic glasses, mostly hues of blue. We use various types of colloidal particles to make photonic glasses, and we study, both theoretically and experimentally, how the optical properties of these glasses relate to their structure and constituent particles. Based on our observations from glasses of conventional particles, we construct a theoretical model that explains the scarcity of yellow, orange, and red photonic glasses. Guided by this model, we develop novel colloidal systems that allow a higher degree of control over structural color. We assemble glasses of soft, core-shell particles with scattering cores and transparent shells, where the resonant wavelength can be tuned independently of the reflectivity. We then encapsulate glasses of these core-shell particles into emulsion droplets of tunable size; in this system, we observe, for the first time, angle-independent structural colors that cover the entire visible spectrum. To enhance color saturation, we begin experimenting with inverse glasses, where the refractive index of the particles is lower than the refractive index of the medium, with promising results. Finally, based on our theoretical model for scattering from colloidal glasses, we begin an exploration of the color gamut that could be achieved with this technique, and we find that photonic glasses are a promising approach to a new type of long-lasting, non-toxic, and

  2. A colloid-facilitated transport model with variable colloid transport properties

    Science.gov (United States)

    Robinson, Bruce A.; Wolfsberg, Andrew V.; Viswanathan, Hari S.; Reimus, Paul W.

    2007-05-01

    Anomalous contaminant transport velocities in groundwater for species generally considered to be immobile are often attributed to the mechanism of colloid-facilitated transport. In some of the field observations attributed to colloid facilitation, an extremely small fraction of the total contaminant mass introduced to the groundwater is detected downstream. In this study, a new model of colloid-facilitated contaminant transport is proposed that explains this phenomenon as the variability of mobility of individual colloids in the population. The process of retardation via attachment and detachment of colloids on immobile surfaces is often modeled with time and space invariant parameters; here it is modeled assuming a diverse population of transport properties that account for the inherent variability of colloid size, surface charge and chemical properties, mineralogy, and the concomitant impact on colloid mobility. When the contaminant is assumed to irreversibly attach to or form colloids, the migration of the contaminant plume exhibits extremely non-Fickian behavior. The plume's center of mass travels with a velocity governed by the groundwater velocity divided by the mean colloid retardation factor. However, small quantities of contaminant attached to a few highly mobile colloids travel at velocities up to the groundwater velocity, far exceeding the velocity of the centroid of the plume. This paper introduces the colloid diversity model, presents some sensitivity calculations for an idealized case, and discusses the implications of such a model on data needs, simulation of field observations, and model scaling.

  3. Frost Heave in Colloidal Soils

    KAUST Repository

    Peppin, Stephen

    2011-01-01

    We develop a mathematical model of frost heave in colloidal soils. The theory accountsfor heave and consolidation while not requiring a frozen fringe assumption. Two solidificationregimes occur: a compaction regime in which the soil consolidates to accommodate the ice lenses, and a heave regime during which liquid is sucked into the consolidated soil from an external reservoir, and the added volume causes the soil to heave. The ice fraction is found to vary inversely with thefreezing velocity V , while the rate of heave is independent of V , consistent with field and laboratoryobservations. © 2011 Society for Industrial and Applied Mathematics.

  4. Synthesis of colloidal silica dumbbells.

    Science.gov (United States)

    Johnson, Patrick M; van Kats, Carlos M; van Blaaderen, Alfons

    2005-11-22

    We describe the synthesis and characterization of stable suspensions of monodisperse fluorescently labeled silica dumbbell particles. Pure dispersions of silica dumbbells with center-to-center lengths from 174 nm to 2.3 microm were produced with a variety of aspect ratios. Individual particles in concentrated dispersions of these particles could be imaged with confocal microscopy. These particles can be used as a colloidal model system for addressing fundamental questions about crystal and glass formation of low-aspect-ratio anisotropic particles. They also have potential in photonic applications and electro-optical devices.

  5. Dynamics of Red Cells in Spleen: How Does Vesiculation Happen?

    Science.gov (United States)

    Zhu, Qiang; Salehyar, Sara; Cabrales, Pedro; Asaro, Robert

    2016-11-01

    Vesiculation of red blood cells as a result of local separation between lipid bilayer and cytoskeleton is known to happen in vivo, most likely inside spleen where they sustain large mechanical loads during the passage through venus slits. There is, however, little knowledge about the detailed scenario and condition. We address this question via a fluid-cell interaction model by coupling a multiscale model of the cell membrane (including molecular details) with a fluid dynamics model based on boundary-integral equations. A numerical flow channel is created where the cell is driven through a narrow slit by pressure (imitating the transit through venus slits in spleen). The concentration is the occurrence of large dissociation (negative) pressure between the skeleton/membrane connection that promotes separation, a precursor of vesicle formation. Critical levels for the negative pressure are estimated using published data. By following the maximum range of pressure, we conclude that for vesiculation to happen there must be biochemical influences (e.g. binding of degraded haemoglobin) that significantly reduce effective attachment density. This is consistent with reported trends in vesiculation that are believed to occur in cases of various hereditary anemias and during blood storage. Our findings also suggest the criticality of understanding the biochemical phenomena involved with cytoskeleton/membrane attachment.

  6. The spleen in the sickling disorders: an update

    Energy Technology Data Exchange (ETDEWEB)

    Khatib, Rana; Sarnaik, Sharada A. [Wayne State University School of Medicine, Children' s Hospital of Michigan, Carmen and Ann Adams Department of Pediatrics, Detroit, MI (United States); Rabah, Raja [Wayne State University School of Medicine, Department of Pathology, Detroit, MI (United States)

    2009-01-15

    In early life, patients with sickle cell disease (SCD) can have acute, life-threatening emergencies related to splenic hypofunction (overwhelming bacterial sepsis), as well as anemic crises from acute splenic sequestration because of sudden pooling of blood in the spleen. The landmark penicillin prophylaxis study in 1985 showed a remarkable decrease in mortality from sepsis in young children with SCD who were treated with oral penicillin prophylaxis compared to placebo. Since that study, newborns are screened for SCD and placed on oral penicillin prophylaxis in nearly all of the United States, as well as in other countries where the disease is highly prevalent. The previously described permanent, complete and nearly universal ''autosplenectomy'' emerging by late childhood or early adulthood is now challenged by recent findings of reversibility of splenic dysfunction by the antisickling drug hydroxyurea or by successful allogeneic stem cell transplantation, even in older patients. Imaging techniques for hypofunction of the spleen are the most commonly used modalities to guide the clinician in decisions regarding medical or surgical management. (orig.)

  7. The spleen in the sickling disorders: an update

    International Nuclear Information System (INIS)

    Khatib, Rana; Sarnaik, Sharada A.; Rabah, Raja

    2009-01-01

    In early life, patients with sickle cell disease (SCD) can have acute, life-threatening emergencies related to splenic hypofunction (overwhelming bacterial sepsis), as well as anemic crises from acute splenic sequestration because of sudden pooling of blood in the spleen. The landmark penicillin prophylaxis study in 1985 showed a remarkable decrease in mortality from sepsis in young children with SCD who were treated with oral penicillin prophylaxis compared to placebo. Since that study, newborns are screened for SCD and placed on oral penicillin prophylaxis in nearly all of the United States, as well as in other countries where the disease is highly prevalent. The previously described permanent, complete and nearly universal ''autosplenectomy'' emerging by late childhood or early adulthood is now challenged by recent findings of reversibility of splenic dysfunction by the antisickling drug hydroxyurea or by successful allogeneic stem cell transplantation, even in older patients. Imaging techniques for hypofunction of the spleen are the most commonly used modalities to guide the clinician in decisions regarding medical or surgical management. (orig.)

  8. Colloidal discs in nematic liquid crystals

    International Nuclear Information System (INIS)

    Silvestre, N M; Patricio, P; Tasinkevych, M; Andrienko, D; Gama, M M Telo da

    2004-01-01

    We use adaptive finite elements methods to investigate a variety of structures in inverted nematic emulsions numerically. In particular, we study dipolar and quadrupolar interactions between colloidal discs in two-dimensional nematics. The behaviour of colloidal particles near a substrate and at a nematic-isotropic interface are also considered

  9. Colloidal Electrolytes and the Critical Micelle Concentration

    Science.gov (United States)

    Knowlton, L. G.

    1970-01-01

    Describes methods for determining the Critical Micelle Concentration of Colloidal Electrolytes; methods described are: (1) methods based on Colligative Properties, (2) methods based on the Electrical Conductivity of Colloidal Electrolytic Solutions, (3) Dye Method, (4) Dye Solubilization Method, and (5) Surface Tension Method. (BR)

  10. Manipulating colloids with charges and electric fields

    NARCIS (Netherlands)

    Leunissen, M.E.

    2007-01-01

    This thesis presents the results of experimental investigations on a variety of colloidal suspensions. Colloidal particles are at least a hundred times larger than atoms or molecules, but suspended in a liquid they display the same phase behavior, including fluid and crystalline phases. Due to their

  11. Colloid transport in saturated porous media: Elimination of attachment efficiency in a new colloid transport model

    Science.gov (United States)

    Landkamer, Lee L.; Harvey, Ronald W.; Scheibe, Timothy D.; Ryan, Joseph N.

    2013-01-01

    A colloid transport model is introduced that is conceptually simple yet captures the essential features of colloid transport and retention in saturated porous media when colloid retention is dominated by the secondary minimum because an electrostatic barrier inhibits substantial deposition in the primary minimum. This model is based on conventional colloid filtration theory (CFT) but eliminates the empirical concept of attachment efficiency. The colloid deposition rate is computed directly from CFT by assuming all predicted interceptions of colloids by collectors result in at least temporary deposition in the secondary minimum. Also, a new paradigm for colloid re-entrainment based on colloid population heterogeneity is introduced. To accomplish this, the initial colloid population is divided into two fractions. One fraction, by virtue of physiochemical characteristics (e.g., size and charge), will always be re-entrained after capture in a secondary minimum. The remaining fraction of colloids, again as a result of physiochemical characteristics, will be retained “irreversibly” when captured by a secondary minimum. Assuming the dispersion coefficient can be estimated from tracer behavior, this model has only two fitting parameters: (1) the fraction of the initial colloid population that will be retained “irreversibly” upon interception by a secondary minimum, and (2) the rate at which reversibly retained colloids leave the secondary minimum. These two parameters were correlated to the depth of the Derjaguin-Landau-Verwey-Overbeek (DLVO) secondary energy minimum and pore-water velocity, two physical forces that influence colloid transport. Given this correlation, the model serves as a heuristic tool for exploring the influence of physical parameters such as surface potential and fluid velocity on colloid transport.

  12. Unclassified haemolytic anaemia with splenomegaly and erythrocyte cation abnormalities - a disease of the spleen

    International Nuclear Information System (INIS)

    Bernard, J.F.; Bournier, O.; Renoux, M.; Charron, D.; Boivin, P.

    1976-01-01

    An unclassified case of haemolytic anaemia with voluminous splenomegaly is reported. This anaemia was normocytic without any specific morphologic aspect of red blood cells (RBC); Coombs test was negative; the osmotic fragility was normal; the increased autohaemolysis was not affected by the presence of glucose; Hb studies were normal; no RBC enzyme deficiency was found; RBC lipids and membrane proteins were normal; there was a marked reduction in RBC survival with exclusive splenic uptake of erythrocytes. Before splenectomy, RBC cations and water content were abnormal: 1) the RBC water was decreased moderately; 2) the RBC sodium was about twice the normal mean with an increased 22 Na turn-over; 3) the RBC potassium was markedly reduced and 42 K influx was twice the normal mean; 4) the RBC calcium content was increased. Splenectomy was followed by rapid disappearance of haemolysis and RBC water and cation disturbances. Because of this extremely rapid disappearance after splenectomy the authors suggest this case of haemolytic anaemia could be a primary disease of the spleen. (author)

  13. Judge of surgical indication for blunt injuries of liver and spleen by CT imaging

    International Nuclear Information System (INIS)

    Nakagawa, Takao; Yokoyama, Toshimitsu; Suga, Hiroyasu; Deguchi, Yoshizumi; Hasegawa, Yasuhiro; Muraoka, Ryusuke; Ishikawa, Masatake; Suzuki, Tadashi.

    1997-01-01

    Recent studies have elucidated that the findings of injuries of parenchimatous organs such as liver and spleen by computed tomography (CT) are consistent with those by surgical operation. But it is still unclear whether CT findings can determine operative indication for blunt injuries of liver and spleen. We performed a retrospective study on 35 lesions of blunt injuries of liver and spleen in 33 cases for blunt injuries of liver and spleen at our hospitals to examine whether CT findings can determine the severity of damage and surgical indication for the injuries, and the following results were obtained. Based on CT findings, the presence of injury was confirmed in all cases except for one lesion. Comparison of CT findings and operative or laparoscopic findings in 12 cases undergoing operation or laparoscopy for liver/spleen injury revealed that the findings of each method were almost the same with few exceptions. When liver/spleen injuries were classified according to the Japanese Association for the Surgery of Trauma (JAST) Classification of injury of liver and spleen, cases with emergency operation had severe injury of Type IIIb for the liver and Type IIIb or higher for the spleen, while conservative treatment was possible for injury cases of Type IIIa or lower of the liver and spleen. From these results, the JAST Classification of these injuries based upon CT imaging was found to be a suitable method for selecting an appropriate treatment for blund injury of liver and spleen. (author)

  14. Judge of surgical indication for blunt injuries of liver and spleen by CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Takao; Yokoyama, Toshimitsu; Suga, Hiroyasu; Deguchi, Yoshizumi; Hasegawa, Yasuhiro; Muraoka, Ryusuke [Fukui Medical School (Japan); Ishikawa, Masatake; Suzuki, Tadashi

    1997-10-01

    Recent studies have elucidated that the findings of injuries of parenchimatous organs such as liver and spleen by computed tomography (CT) are consistent with those by surgical operation. But it is still unclear whether CT findings can determine operative indication for blunt injuries of liver and spleen. We performed a retrospective study on 35 lesions of blunt injuries of liver and spleen in 33 cases for blunt injuries of liver and spleen at our hospitals to examine whether CT findings can determine the severity of damage and surgical indication for the injuries, and the following results were obtained. Based on CT findings, the presence of injury was confirmed in all cases except for one lesion. Comparison of CT findings and operative or laparoscopic findings in 12 cases undergoing operation or laparoscopy for liver/spleen injury revealed that the findings of each method were almost the same with few exceptions. When liver/spleen injuries were classified according to the Japanese Association for the Surgery of Trauma (JAST) Classification of injury of liver and spleen, cases with emergency operation had severe injury of Type IIIb for the liver and Type IIIb or higher for the spleen, while conservative treatment was possible for injury cases of Type IIIa or lower of the liver and spleen. From these results, the JAST Classification of these injuries based upon CT imaging was found to be a suitable method for selecting an appropriate treatment for blund injury of liver and spleen. (author)

  15. Fluorodeoxyglucose-positron emission tomography/computed tomography imaging features of colloid adenocarcinoma of the lung: a case report.

    Science.gov (United States)

    Wang, ZhenGuang; Yu, MingMing; Chen, YueHua; Kong, Yan

    2017-07-27

    Colloid adenocarcinoma of the lung is a rare subtype of variants of invasive adenocarcinomas. We report the appearance of this unusual entity on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography. A 60-year-old man of Chinese Han nationality coughed with a little white sputum for 1 month. Chest computed tomography showed multiple bilateral subpleural nodules and plaques accompanied by air bronchograms, which were most concentrated in the lower lobe of his right lung. Positron emission tomography indicated increased radioactivity uptake with a maximum standardized uptake value of 3.5. Positron emission tomography/computed tomography showed a soft tissue density lesion in his left adrenal gland with a maximum standardized uptake value of 4.1. The positron emission tomography/computed tomography appearance suggested a primary colloid adenocarcinoma in the lower lobe of his right lung accompanied by intrapulmonary and left adrenal gland metastases. The diagnostic rate of colloid adenocarcinoma can be increased by combining the anatomic and metabolic information of lesions. The advantage of positron emission tomography/computed tomography in the diagnosis of colloid adenocarcinoma, as with other cancers, is the ability to locate extrapulmonary disease, facilitating clinical staging.

  16. Stable colloids in molten inorganic salts

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hao; Dasbiswas, Kinjal; Ludwig, Nicholas B.; Han, Gang; Lee, Byeongdu; Vaikuntanathan, Suri; Talapin, Dmitri V.

    2017-02-15

    A colloidal solution is a homogeneous dispersion of particles or droplets of one phase (solute) in a second, typically liquid, phase (solvent). Colloids are ubiquitous in biological, chemical and technological processes1, 2, homogenizing highly dissimilar constituents. To stabilize a colloidal system against coalescence and aggregation, the surface of each solute particle is engineered to impose repulsive forces strong enough to overpower van der Waals attraction and keep the particles separated from each other2. Electrostatic stabilization3, 4 of charged solutes works well in solvents with high dielectric constants, such as water (dielectric constant of 80). In contrast, colloidal stabilization in solvents with low polarity, such as hexane (dielectric constant of about 2), can be achieved by decorating the surface of each particle of the solute with molecules (surfactants) containing flexible, brush-like chains2, 5. Here we report a class of colloidal systems in which solute particles (including metals, semiconductors and magnetic materials) form stable colloids in various molten inorganic salts. The stability of such colloids cannot be explained by traditional electrostatic and steric mechanisms. Screening of many solute–solvent combinations shows that colloidal stability can be traced to the strength of chemical bonding at the solute–solvent interface. Theoretical analysis and molecular dynamics modelling suggest that a layer of surface-bound solvent ions produces long-ranged charge-density oscillations in the molten salt around solute particles, preventing their aggregation. Colloids composed of inorganic particles in inorganic melts offer opportunities for introducing colloidal techniques to solid-state science and engineering applications.

  17. Nonlinear rheology of colloidal dispersions

    International Nuclear Information System (INIS)

    Brader, J M

    2010-01-01

    Colloidal dispersions are commonly encountered in everyday life and represent an important class of complex fluid. Of particular significance for many commercial products and industrial processes is the ability to control and manipulate the macroscopic flow response of a dispersion by tuning the microscopic interactions between the constituents. An important step towards attaining this goal is the development of robust theoretical methods for predicting from first-principles the rheology and nonequilibrium microstructure of well defined model systems subject to external flow. In this review we give an overview of some promising theoretical approaches and the phenomena they seek to describe, focusing, for simplicity, on systems for which the colloidal particles interact via strongly repulsive, spherically symmetric interactions. In presenting the various theories, we will consider first low volume fraction systems, for which a number of exact results may be derived, before moving on to consider the intermediate and high volume fraction states which present both the most interesting physics and the most demanding technical challenges. In the high volume fraction regime particular emphasis will be given to the rheology of dynamically arrested states. (topical review)

  18. Colloid centrifugation of boar semen.

    Science.gov (United States)

    Morrell, J M; Wallgren, M

    2011-09-01

    Colloid centrifugation of boar semen has been reported sporadically for at least the last two decades, beginning with density gradient centrifugation (DGC) and progressing more recently to single layer centrifugation (SLC). Single layer centrifugation through a species-specific colloid has been shown to be effective in selecting the best spermatozoa (spermatozoa with good motility and normal morphology) from boar sperm samples. The method is easier to use and less time-consuming than DGC and has been scaled-up to allow whole ejaculates from other species, e.g. stallions, to be processed in a practical manner. The SLC technique is described, and various scale-up versions are presented. The potential applications for SLC in boar semen preservation are as follows: to improve sperm quality in artificial insemination (AI) doses for 'problem' boars; to increase the shelf-life of normal stored sperm samples, either by processing the fresh semen before preparing AI doses or by processing the stored semen dose to extract the best spermatozoa; to remove pathogens (viruses, bacteria), thus improving biosecurity of semen doses and potentially reducing the use of antibiotics; to improve cryosurvival by removing dead and dying spermatozoa prior to cryopreservation; to select spermatozoa for in vitro fertilization. These applications are discussed and practical examples are provided. Finally, a few thoughts about the economic value of the technique to the boar semen industry are presented. © 2011 Blackwell Verlag GmbH.

  19. Hemoperitoneum secondary to an spontaneous rupture of the spleen mimmicking a duodenal perforated ulcera: A case report.

    Science.gov (United States)

    Ruiz-Tovar, Jaime; Díaz, Gustavo; Alias, David; Jiménez-Fuertes, Montiel; Durán, Manuel

    2016-01-01

    Spontaneous rupture of the spleen without traumatic cause is an unfrequent entity, usually related with pathologic spleens. We present a case of spontaneous rupture of an histologically normal spleen with splenomegalia secondary to smoking habit. The hemoperitoneum caused by the spontaneous rupture of the spleen mimmicked a hollow viscera perforation.

  20. Accumulation of Tc99m-DMSA-3 in the spleen in a case of multiple myeloma with associated amyloidosis

    Directory of Open Access Journals (Sweden)

    Barai Sukanta

    2005-01-01

    Full Text Available We describe a case of a 58-year-old male with longstanding hypertension and Type 2 diabetes mellitus who developed sudden onset renal impairment. The first clue to the possible presence of amyloidosis in this case was provided by the radionuclide renal cortical scan performed with trivalent dimercapto succinic acid (Tc99m-DMSA-3, which revealed intense tracer uptake in the spleen suggesting amyloid deposit. Further workup to ascertain the cause of amyloidosis led to the diagnosis of multiple myeloma. We conclude that in cases of extra-renal or splenic accumulation of Tc99m-DMSA-3, a diagnosis of amyloidosis should be considered, in an appropriate clinical setting.

  1. Polymer-Induced Depletion Interaction and Its Effect on Colloidal Sedimentation in Colloid-Polymer Mixtures

    Science.gov (United States)

    Tong, Penger

    1996-01-01

    In this paper we focus on the polymer-induced depletion attraction and its effect on colloidal sedimentation in colloid-polymer mixtures. We first report a small angle neutron scattering (SANS) study of the depletion effect in a mixture of hard-sphere-like colloid and non-adsorbing polymer. Then we present results of our recent sedimentation measurements in the same colloid-polymer mixture. A key parameter in controlling the sedimentation of heavy colloidal particles is the interparticle potential U(tau), which is the work required to bring two colloidal particles from infinity to a distance tau under a give solvent condition. This potential is known to affect the average settling velocity of the particles and experimentally one needs to have a way to continuously vary U(tau) in order to test the theory. The interaction potential U(tau) can be altered by adding polymer molecules into the colloidal suspension. In a mixture of colloid and non-adsorbing polymer, the potential U(tau) can develop an attractive well because of the depletion effect, in that the polymer chains are expelled from the region between two colloidal particles when their surface separation becomes smaller than the size of the polymer chains. The exclusion of polymer molecules from the space between the colloidal particles leads to an unbalanced osmotic pressure difference pushing the colloidal particles together, which results in an effective attraction between the two colloidal particles. The polymer-induced depletion attraction controls the phase stability of many colloid-polymer mixtures, which are directly of interest to industry.

  2. Colloid transport and retention in unsaturated porous media: effect of colloid input concentration.

    Science.gov (United States)

    Zhang, Wei; Morales, Verónica L; Cakmak, M Ekrem; Salvucci, Anthony E; Geohring, Larry D; Hay, Anthony G; Parlange, Jean-Yves; Steenhuis, Tammo S

    2010-07-01

    Colloids play an important role in facilitating transport of adsorbed contaminants in soils. Recent studies showed that under saturated conditions colloid retention was a function of its concentration. It is unknown if this is the case under unsaturated conditions. In this study, the effect of colloid concentration on colloid retention was investigated in unsaturated columns by increasing concentrations of colloid influents with varying ionic strength. Colloid retention was observed in situ by bright field microscopy and quantified by measuring colloid breakthrough curves. In our unsaturated experiments, greater input concentrations resulted in increased colloid retention at ionic strength above 0.1 mM, but not in deionized water (i.e., 0 mM ionic strength). Bright field microscope images showed that colloid retention mainly occurred at the solid-water interface and wedge-shaped air-water-solid interfaces, whereas the retention at the grain-grain contacts was minor. Some colloids at the air-water-solid interfaces were rotating and oscillating and thus trapped. Computational hydrodynamic simulation confirmed that the wedge-shaped air-water-solid interface could form a "hydrodynamic trap" by retaining colloids in its low velocity vortices. Direct visualization also revealed that colloids once retained acted as new retention sites for other suspended colloids at ionic strength greater than 0.1 mM and thereby could explain the greater retention with increased input concentrations. Derjaguin-Landau-Verwey-Overbeek (DLVO) energy calculations support this concept. Finally, the results of unsaturated experiments were in agreement with limited saturated experiments under otherwise the same conditions.

  3. Pathomorphology of spleen lymphocyte apoptosis in large dose 60Co γ-irradiated mice

    International Nuclear Information System (INIS)

    Gao Linlu; Cui Yufang; Yang Hong; Xia Guowei; Peng Ruiyun; Gao Yabing; Wang Dewen

    2000-01-01

    Objective: The aim of the authors was to investigate the pathomorphology changes of spleen lymphocyte apoptosis after 60 Co γ-irradiation. Methods: The mice were irradiated with 6, 9, 12, 15 and 20 Gy of 60 Co γ-rays. At different times after irradiation, the mice were sacrificed and the pathological changes of spleen lymphocyte were observed by light and transmission electron microscopies. Results: Spleen lymphocyte decreased evidently and the peak of apoptosis in spleen lymphocyte was dependent on radiation dose and the time after irradiation. Conclusion: After γ-irradiation with large doses, pathological changes of spleen lymphocyte apoptosis in mice can be divided into obviously different stages. The main causes of death of spleen lymphocytes are different in different dose groups

  4. Role of nuclear medicine imaging in differential diagnosis of accessory spleens in patients after splenectomy

    International Nuclear Information System (INIS)

    D’Amico, Andrea; Cofalik, Anna; Przeorek, Cesary; Gawlik, Tomasz; Olczyk, Tomasz; Kalemba, Michał; Modorowska, Alicja; Turska-d’Amico, Maria; Bobek-Billewicz, Barbara; Jarzab, Barbara

    2012-01-01

    More than 10% of healthy population has one or more accessory spleens. The most common location is the hilum of the spleen or area near the tail of the pancreas. The radiological appearance of accessory spleens in oncologic patients who underwent splenectomy can be misinterpreted as a recurrence, especially in the case of compensatory growth of an accessory spleen in successive radiological examinations. We present the cases of three patients who underwent splenectomy for gastric carcinoid, gastric adenocarcinoma and cancer of the left adrenal gland, respectively. CT examination and/or PET-CT scan revealed suspicious findings in the left upper abdomen. In one patient, the dimensional increase of this finding in successive examinations was initially considered suggestive for cancer recurrence. Scintigraphy with 99m Tc-nanocolloid was able to confirm the presence of an accessory spleen in all these patients. Splenic scintigraphy is an economical, accessible and accurate tool in differential diagnosis of accessory spleens in patients after splenectomy

  5. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Videos About Us News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan ... for several hours before your exam because eating can affect the accuracy of the uptake measurement. Jewelry ...

  6. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... the limitations of the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid ... body converts food to energy. top of page What are some common uses of the procedure? The ...

  7. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Scan and Uptake Thyroid scan and uptake uses small amounts of radioactive materials called radiotracers, a special ... is a branch of medical imaging that uses small amounts of radioactive material to diagnose and determine ...

  8. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... capturing images of the thyroid gland from three different angles. You will need to remain still for ... Often, two separate uptake measurements are obtained at different times. For example, you may have uptake measurements ...

  9. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... uptake measurements are obtained at different times. For example, you may have uptake measurements at four to ... medicine procedures can be time consuming. It can take several hours to days for the radiotracer to ...

  10. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... of the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is ... taking our brief survey: Survey Do you have a personal story about radiology? Share your patient story ...

  11. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Uptake? A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) ... of thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that ...

  12. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Uptake? A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is ... of thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that uses ...

  13. Relative radiosensitivities of the thymus, spleen, and lymphohemopoietic systems

    International Nuclear Information System (INIS)

    Maruyama, Y.; Feola, J.M.

    1987-01-01

    Recently, dramatic advances have taken place in our knowledge of the organization and functions of the thymus and lymphoid system. Some of our understanding has come form the application of radiation therapy to diseases derived from lymphoid organs. Human investigations using radiotherapy have shed light on the radiosensitivities of the system as well as on its important functional activities. Likewise, studies of cellular traffic in the lymphoid organs, i.e., the thymus, spleen, and lymph nodes, showed that extensive cellular exchange occurs between the bone marrow compartment with its hemopoietic and progenitor cells and the various central and peripheral lymphoid organs. Because this is so, the term lymphohemopoietic (LH) system is appropriate. This very selective review will recapitulate some of the ongoing research in radiotherapy and radiobiology in these closely related fields. The clinical therapeutic advances have taken place in four important settings closely related to clinical therapy of tumor derived from the LH system

  14. Cat scratch disease with lymphadenitis, vertebral osteomyelitis, and spleen abscesses.

    Science.gov (United States)

    Rolain, J M; Chanet, V; Laurichesse, H; Lepidi, H; Beytout, J; Raoult, D

    2003-06-01

    In this report we describe a 30-year old male patient with vertebral osteomyelitis and spleen abscesses with cat scratch disease. The diagnosis was made on the basis of molecular detection of Bartonella henselae either on lymph node biopsies or on bone biopsy, histology of the lymph node, serology using either our in-house microimmunofluorescence assay or a commercial kit (Focus Technologies). Immunofluorescent detection was also performed directly on slide appositions using a monoclonal antibody. Treatment consisted of administration of antibiotics with rapid clinical improvement and a stabilization of skeletal lesions on the magnetic resonance imaging performed three months later. Twenty two other cases of this unusual manifestation associated with cat scratch disease have been reported in the literature and are reviewed here. Our case represents the second case of osteomyelitis associated with cat scratch disease in which B. henselae has been specifically identified as the etiological agent using several direct and indirect methods.

  15. Primary hemangiosarcoma of the spleen with angioscintigraphic demonstration of metastases

    Energy Technology Data Exchange (ETDEWEB)

    Hermann, G.G.; Fogh, J.; Graem, N.; Hansen, O.P.; Hippe, E.

    1984-04-15

    A case of primary hemangiosarcoma of the spleen in a 48-year-old woman is presented. Twenty-eight months after splenectomy the patient developed a severe anemia of the microangiopathic type, thrombocytopenia, and a leukoerythroblastic peripheral blood picture. In contrast to x-ray and conventional /sup 99m/Tc-methylene-diphosphonate (MDP) bone scintigraphy, which showed only a few minor focal changes in the spine and ribs, angioscintigraphy with in vitro labeled /sup 99m/Tc-erythrocytes revealed extensive pathologic accumulations throughout the spine, femurs, and the liver, indicating the presence of extremely vascular metastases. Autopsy 15 months later confirmed the scintigraphic findings. Angiography with /sup 99m/Tc-labeled erythrocytes seems to be useful for monitoring metastases from hemangiosarcomas.

  16. Numerical Analysis of Colloid Transport in Volcanic Ash Soil

    Science.gov (United States)

    Saito, H.; Kawamoto, K.; Komatsu, T.; Moldrup, P.; Simunek, J.

    2006-12-01

    Many studies have been conducted to investigate colloid-facilitated transport of organic or inorganic contaminants in soils. Because many contaminants, even non-soluble contaminants, can sorb onto colloids, failure to account for colloid-facilitated transport may lead to significant errors in predicting movement of contaminants in soils. Volcanic ash soils usually contain a considerable amount of soil particles smaller than 1 micrometer that are considered to have colloidal properties. This study investigated experimentally and numerically the transport of such colloidal particles in a volcanic ash soil called Tachikawa loam under simulated rainfall conditions. Disturbed soil columns were irrigated by controlled rainfall events using artificial rain water (ARW) and colloid solution extracted from Tachikawa loam soil (soil particles smaller than 1 micrometer). There was a continuous leaching of natural colloids with an initial increase in concentrations followed by a long tailing even when irrigated only by ARW. When colloid solution was applied, the breakthrough curve of the applied colloid showed no tailing and least time lag. HYDRUS-1D was used to obtain transport parameters of natural and applied colloids from breakthrough curves using a standard colloid transport model with the first-order deposition and entrainment coefficients (i.e., attachment and detachment terms) to account for kinetic sorption. The estimated distribution coefficient of natural colloids was an order of magnitude larger than that of applied colloids. While the estimated attachment coefficient of natural colloids was negligible, that of applied colloids led to a high retention of applied colloids in soils. The estimated detachment coefficient of natural colloids was three to four orders of magnitude greater than that of applied colloids. One possible explanation is that the estimated attachment coefficient for applied colloids may account for so-called straining that is a physical filtration

  17. Phosphate binding by natural iron-rich colloids in streams

    NARCIS (Netherlands)

    Baken, S.; Moens, C.; Griffioen, J.J.; Smolders, E.

    2016-01-01

    Phosphorus (P) in natural waters may be bound to iron (Fe) bearing colloids. However, the natural variation in composition and P binding strength of these colloids remain unclear. We related the composition of "coarse colloids" (colloids in the 0.1-1.2 μm size range) in 47 Belgian streams to the

  18. Synthesis and Analytical Centrifugation of Magnetic Model Colloids

    NARCIS (Netherlands)

    Luigjes, B.

    2012-01-01

    This thesis is a study of the preparation and thermodynamic properties of magnetic colloids. First, two types of magnetic model colloids are investigated: composite colloids and single-domain nanoparticles. Thermodynamics of magnetic colloids is studied using analytical centrifugation, including a

  19. GM-CSF augments the immunosuppressive capacity of neonatal spleen cells in vitro

    International Nuclear Information System (INIS)

    Morrissey, P.J.; Ireland, R.

    1991-01-01

    Addition of exogenous granulocyte-macrophage colony stimulating factor (GM-CSF) to cultures of adult murine spleen cells with sheep red blood cells (SRBC) results in an augmented plaque forming cell (PFC) response. The influence of GM-CSF on the ability of neonatal spleen cells to suppress the anti-SRBC plaque forming response of adult spleen cells was tested by adding GM-CSF to cultures of neonatal and adult spleen cells. The suppressive capacity of the neonatal spleen cells was augmented by exogenous GM-CSF. The augmented suppression of the neonatal spleen cells was dependent on a G-10 adherent population since the addition of GM-CSF to cultures containing G-10 passed neonatal spleen cells resulted in an augmented PFC response and not suppression. Neonatal splenic glass adherent cells were also capable of suppressing the response. Neonatal spleen cells or purified neonatal glass adherent spleen cells cultured in the presence of GM-CSF had markedly increased levels of PGE2 in the culture supernatant. Neonatal spleen cells cultured with GM-CSF had increased numbers of morphologically identifiable macrophages after 48 hr of culture. Both irradiation and G-10 passage of the neonatal spleen diminished the numbers of macrophages formed in response to GM-CSF, and both of these manipulations resulted in reversal of suppression in response to GM-CSF. Thus, the augmented suppressive capacity of neonatal spleen cells in response to GM-CSF is probably mediated by its ability to drive monocyte to macrophage differentiation as well as increase the suppressive capacity of the existing neonatal splenic macrophages by increasing their production of PGE2

  20. Single-Incision Laparoscopic Splenectomy and Splenic Autotransplantation for an Enlarged Wandering Spleen with Torsion

    OpenAIRE

    Katsura, Shunsaku; Kawamura, Daichi; Harada, Eijiro; Enoki, Tadahiko; Hamano, Kimikazu

    2013-01-01

    A wandering spleen is a rare condition in which the spleen is not located in the left upper quadrant, but instead is found in the lower abdomen or in the pelvic region because of the laxity of the peritoneal attachments. The unusually long pedicle is susceptible to twisting, which can lead to ischemia, and eventually to necrosis. We herein report a case of an enlarged wandering spleen with torsion, successfully treated by single-incision laparoscopic splenectomy and autotransplantation. The t...

  1. Torsion of the accessory spleen with infarction : CT features in a case report

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Jung Kyung; Lee, Jun Sik; Kim, Mee Eun; Pyun, Hae Wook; Lee, Il Gi; Lee, Jong Gil; Kim, Hee Jin; Kim, Ik Su [Fatima Hospital, Taegu (Korea, Republic of)

    2000-05-01

    Torsion of the accessory spleen is a rare entity that can have variable clinical presentations. We report case involving an 11-year-old boy with severe abdominal pain and a mass that was found to be due to infarction of the accessory spleen, which was twisted on its pedicle. CT revealed a low-attenuating mass with peripheral inflammatory changes in the left upper abdomen. The mass was pathologically confirmed as torsion of the accessory spleen with infarction. (author)

  2. Development of a colloidal gold immunochromatographic strip for rapid detection of Streptococcus agalactiae in tilapia.

    Science.gov (United States)

    Wen-de, Wu; Min, Li; Ming, Chen; Li-Ping, Li; Rui, Wang; Hai-Lan, Chen; Fu-Yan, Chen; Qiang, Mi; Wan-Wen, Liang; Han-Zhong, Chen

    2017-05-15

    A colloidal gold immunochromatographic strip was developed for rapid detection of Streptococcus agalactiae (S. agalactiae) infection in tilapia. The monoclonal antibodies (mAb) 4C12 and 3A9 were used to target S. agalactiae as colloidal gold-mAb conjugate and captured antibody, respectively. The colloidal gold immunochromatographic strip was assembled via routine procedures. Optimal pH and minimum antibody levels in the reaction system for gold colloidal-mAb 4C12 conjugation were pH 7.4 and 18μg/mL, respectively. Optimal concentrations of the captured antibody 3A9 and goat anti-mouse antibody were 0.6mg/mL and 2mg/mL, respectively. The sensitivity of the strip for detecting S. agalactiae was 1.5×10 5 colony forming units (CFU). No cross-reaction was observed with other commonly encountered bacteria, including Pseudomonas fluorescens, Aeromonas hydrophila, Vibrio anguillarum and Streptococcus iniae. The assay time for S. agalactiae was less than 15min. Tilapia samples artificially infected with S. agalactiae were tested using the newly developed strip. The results indicated that blood, brain, kidney, spleen, metanephros and intestine specimens of infected fish can be used for S. agalactiae detection. The validity of the strip was maintained for 6 months at 4°C. These findings suggested that the immunochromatographic strip was effective for spot and rapid detection of S. agalactiae infected tilapia. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Towards conducting inks: Polypyrrole–silver colloids

    International Nuclear Information System (INIS)

    Omastová, Mária; Bober, Patrycja; Morávková, Zuzana; Peřinka, Nikola; Kaplanová, Marie; Syrový, Tomáš; Hromádková, Jiřina; Trchová, Miroslava; Stejskal, Jaroslav

    2014-01-01

    Graphical abstract: - Highlights: • Composite colloidal particles combining conducting polymer and metal have been prepared. • Conducting colloids are suitable for printing applications. • Polypyrrole/silver colloids are prepared in a single reaction step. • The conductivity control is discussed and still needs improvement. - Abstract: The oxidation of pyrrole with silver nitrate in the presence of suitable water-soluble polymers yields composite polypyrrole–silver colloids. The polypyrrole–silver nanoparticles stabilized with poly(N-vinylpyrrolidone) have a typical size around 350 nm and polydispersity index 0.20, i.e. a moderate polydispersity in size. Similar results have been obtained with poly(vinyl alcohol) as stabilizer. The effect of stabilizer concentration on the particle size is marginal. In the present study, several types of stabilizers have been tested in addition to currently used poly(N-vinylpyrrolidone). Transmission electron microscopy and optical microscopy revealed the gemini morphology of polypyrrole and silver colloidal nanoparticles and confirmed their size and size-distribution determined by dynamic light scattering. The use of colloidal dispersions provides an efficient tool for the UV–vis and FT Raman spectroscopic characterization of polypyrrole, including the transition between polypyrrole salt and corresponding polypyrrole base. The dispersions were used for the preparation of coatings on polyethylene terephthalate foils, and the properties for polypyrrole–silver composites have been compared with those produced from polypyrrole colloids alone

  4. The physics of the colloidal glass transition.

    Science.gov (United States)

    Hunter, Gary L; Weeks, Eric R

    2012-06-01

    As one increases the concentration of a colloidal suspension, the system exhibits a dramatic increase in viscosity. Beyond a certain concentration, the system is said to be a colloidal glass; structurally, the system resembles a liquid, yet motions within the suspension are slow enough that it can be considered essentially frozen. For several decades, colloids have served as a valuable model system for understanding the glass transition in molecular systems. The spatial and temporal scales involved allow these systems to be studied by a wide variety of experimental techniques. The focus of this review is the current state of understanding of the colloidal glass transition, with an emphasis on experimental observations. A brief introduction is given to important experimental techniques used to study the glass transition in colloids. We describe features of colloidal systems near and in glassy states, including increases in viscosity and relaxation times, dynamical heterogeneity and ageing, among others. We also compare and contrast the glass transition in colloids to that in molecular liquids. Other glassy systems are briefly discussed, as well as recently developed synthesis techniques that will keep these systems rich with interesting physics for years to come.

  5. The physics of the colloidal glass transition

    International Nuclear Information System (INIS)

    Hunter, Gary L; Weeks, Eric R

    2012-01-01

    As one increases the concentration of a colloidal suspension, the system exhibits a dramatic increase in viscosity. Beyond a certain concentration, the system is said to be a colloidal glass; structurally, the system resembles a liquid, yet motions within the suspension are slow enough that it can be considered essentially frozen. For several decades, colloids have served as a valuable model system for understanding the glass transition in molecular systems. The spatial and temporal scales involved allow these systems to be studied by a wide variety of experimental techniques. The focus of this review is the current state of understanding of the colloidal glass transition, with an emphasis on experimental observations. A brief introduction is given to important experimental techniques used to study the glass transition in colloids. We describe features of colloidal systems near and in glassy states, including increases in viscosity and relaxation times, dynamical heterogeneity and ageing, among others. We also compare and contrast the glass transition in colloids to that in molecular liquids. Other glassy systems are briefly discussed, as well as recently developed synthesis techniques that will keep these systems rich with interesting physics for years to come. (review article)

  6. Direct visualization of colloidal liquids

    Science.gov (United States)

    Durand, Richard Vernon

    We have investigated various colloidal systems consisting of aqueous suspensions of micron sized polystyrene particles. These systems are appealing because they provide a fertile testing ground for theories of both the liquid and solid states, as well as for theories describing hydrodynamic interactions. Our first study of colloidal systems was motivated by some interesting observations we made while looking at a suspension under a light microscope. We, as well as other workers, noticed that particles undergoing Brownian motion can appear to linger around each other for long periods of time. The question arose as to whether this lingering was a product of interparticle interactions, or was an artifact due to random thermal motion and projection onto a two dimensional image plane. We found that the latter was true, which drove home the idea that we must be wary of our own biases when making scientific observations. During the course of the research on this lingering behavior, we developed a mathematical technique for generating successively more accurate approximate analytical solutions to initial value linear partial differential equations which are first order in time and have no mixing of spatial and time derivatives. This formalism is especially useful for diffusion problems, since the analytical approximation conserves probability at each order of approximation. Our next experimental effort involved colloidal systems in which the suspending medium was carefully prepared to promote long ranged electrostatic interactions between the particles. The interaction potential in such a suspension has been the topic of much research recently. Using digital video microscopy, as well as techniques we developed allowing the proper analysis of two dimensional data, we found that the interaction length in our samples was surprisingly short ranged compared to what we expected based on our water purification experiments. The problems with projection effects associated with two

  7. Characterization of Metal Ion ­ Colloid Interaction: Impact On Colloid-facilitated Transport

    Science.gov (United States)

    Specht, C. H.; Schmitt, D.; Kaulisch, E.-M.; Frimmel, F. H.

    It is generally accepted, that metal transport in natural aquatic systems strongly de- pends on the metal binding form. Besides complex formation with well defined inor- ganic and organic ligands, the interaction with colloidal particles and soil material is one of the most important reactions of metal ions in aquatic systems. Mobile colloids compete with the stationary soil matrix for binding of metal ions and might facili- tate their transport. Important representatives for mineral and organic colloids are clay minerals and natural organic matter (NOM), respectively. In this work, the interaction of metal ions with clay minerals and NOM is characterized by coupling of asymmetric flow field-flow fractionation AF4 to inductively coupled plasma ­ mass spectrometry (ICPMS). A method for separating mineral from organic colloids is presented, which allows to quantify the amount of metals being bound to either colloid. For different metal ions (Cu, Zn, Pb, Pt) and a metalloid (As) a different extent of binding to either colloid was found.The information obtained from the AF4-ICPMS measurements was useful for the understanding of the observations from column experiments which were conducted to quantify the colloid-facilitated metal transport. In column experiments, the transport of the mineral colloids itself and the influence of NOM onto the colloid transport were investigated. Furthermore, the dependance of colloid transport from the ionic strength and the pH value was elucidated. In order to get information about the co-transport of metal ions by organic and mineral colloids, metal ions were adsorbed onto the colloidal material and a distribution coef- ficient of the metal ions between the colloidal phase and the solution was determined. The colloidal suspension containing both, "free" and adsorbed metal ions were then injected onto the column. The direct metal breakthrough caused by colloidal trans- port was detected at the column outlet. The results clearly

  8. Assembly of open clusters of colloidal dumbbells via droplet evaporation.

    Science.gov (United States)

    Pham Van, Hai; Fortini, Andrea; Schmidt, Matthias

    2016-05-01

    We investigate the behavior of a mixture of asymmetric colloidal dumbbells and emulsion droplets by means of kinetic Monte Carlo simulations. The evaporation of the droplets and the competition between droplet-colloid attraction and colloid-colloid interactions lead to the formation of clusters built up of colloid aggregates with both closed and open structures. We find that stable packings and hence complex colloidal structures can be obtained by changing the relative size of the colloidal spheres and/or their interfacial tension with the droplets.

  9. Laparoscopic versus open splenectomy: the impact of spleen size on outcomes.

    Science.gov (United States)

    Ardestani, Ali; Tavakkoli, Ali

    2013-09-01

    Although laparoscopic splenectomy (Lap-Spleen) has become the standard surgical approach for normal-sized spleens, open splenectomy (Open-Spleen) is still recommended by many in the setting of splenomegaly. We set out to compare the impact of spleen size on Lap-Spleen and Open-Spleen outcomes using a national database. We reviewed the American College of Surgeons' National Surgical Quality Improvement Program database to identify patients who had undergone non-emergency splenectomy during 2005-2010. To evaluate the impact of spleen size on outcomes, we considered patients with diagnoses of splenomegaly and hypersplenism as those having large spleens (Large-Sp group) and those with diagnoses of primary thrombocytopenia and immune thrombocytopenic purpura as having normal spleens (Normal-Sp group). Patients were also categorized based on surgical approach into Lap-Spleen and Open-Spleen groups. We identified 639 patients in the Large-Sp group and 879 patients in the Normal-Sp group. During 2005-2010 laparoscopy was used in 84.2% of cases in the Normal-Sp group (annual range, 77.8%-90.8%). However, the rate of laparoscopy in the Large-Sp group remained consistently below 50% with an average of 41.8% (annual range, 20%-47%). In the Lap-Spleen group, those with Large-Sp had longer operative time and length of stay and higher blood transfusion and morbidity compared with the Normal-Sp group. However, when looking specifically at the Large-Sp group, patients with Open-Spleen had more transfusion requirements, longer length of stay, and higher morbidity, compared with those with Lap-Spleen. Lap-Spleen leads to significant improvement in outcomes. These advantages were believed to be limited to normal-sized spleens, but this study demonstrates that laparoscopy can still be advantageous in patients with splenomegaly. We hope such data encourages wider utilization of laparoscopy in the setting of splenomegaly, especially among surgeons who are experienced with the technique.

  10. Effects of aluminum trichloride on the trace elements and cytokines in the spleen of rats.

    Science.gov (United States)

    Zhu, Yanzhu; Li, Xinwei; Chen, Chongxiao; Wang, Fan; Li, Jing; Hu, Chongwei; Li, Yanfei; Miao, Liguang

    2012-08-01

    The bioaccumulation and immunotoxicity of aluminum (Al) have been previously documented. Al accumulates in the organs of the organism, including spleen. Spleen is a peripheral organ of the immune system. The accumulated Al may alter the immune function. Here, we investigated the bioaccumulation of Al in spleen and its alterations in the immune system. Forty male Wistar rats (5 weeks old) weighed 110-120 g were orally exposed to aluminum trichloride (AlCl(3)) (0, 64.18, 128.36 and 256.72 mg/kg body weight) in drinking water for 120 days. The concentrations of spleen's Al, iron (Fe), copper (Cu), zinc (Zn), interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α) and growth index were examined at the end of the experiment. The results showed that the concentrations of Al and Cu in the spleen were increased in an AlCl(3)-dose dependent manner, and the concentrations of spleen's growth index, Fe, Zn, IL-2 and TNF-α were reduced in AlCl(3)-treated rats. The results suggest that AlCl(3) can suppress the growth of spleen, disorder the balance of trace elements and inhibit the immune regulation of cytokines in the spleen. It indicates that AlCl(3) suppresses the immune function of spleen. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Role of the spleen in cyclophosphamide-induced hematosuppression and extramedullary hematopoiesis in mice.

    Science.gov (United States)

    Wang, Yuli; Meng, Qinggang; Qiao, Haiquan; Jiang, Hongchi; Sun, Xueying

    2009-05-01

    Extramedullary hematopoiesis (EMH) is induced in spleens due to various diseases. The aim of this study is to investigate the role of spleen in cyclophosphamide (CTX)-induced hematosuppression and EMH in mice. Balb/c mice were IP injected with 300 mg/kg CTX 2 weeks after splenectomy or sham operation and randomly sacrificed 1, 3, 7, 14, and 21 days after injection. Blood samples were collected, and spleens were weighed, histologically analyzed, and then used for flow cytometry. There were significant differences in white blood count, red blood count, platelet numbers and hemoglobin concentration between the splenectomized and sham-operated mice after CTX injection. The cellularity of the spleen was reduced 3 days following CTX treatment but then rose 7 days after CTX treatment. The numbers of colony-forming units in the spleen reached a peak 7 days after CTX injection, then declined. Flow cytometry demonstrated the percentage of CD34(+) and CD117(+) cells in the spleen increased 7 days after CTX injection, indicating the hematopoietic stem and progenitor cells in the spleen. The study indicates that EMH occurs as a compensatory reaction to CTX-induced hematosuppression in the murine spleen, implying that conservation of the spleen may promote the recovery of cancer patients from chemotherapy-induced hematosuppression.

  12. Interactions between Biliverdin, Oxidative Damage, and Spleen Morphology after Simulated Aggressive Encounters in Veiled Chameleons.

    Directory of Open Access Journals (Sweden)

    Michael W Butler

    Full Text Available Stressors frequently increase oxidative damage--unless organisms simultaneously mount effective antioxidant responses. One putative mitigative mechanism is the use of biliverdin, an antioxidant produced in the spleen during erythrocyte degradation. We hypothesized that both wild and captive-bred male veiled chameleons (Chamaeleo calyptratus, which are highly aggressive to conspecifics, would respond to agonistic displays with increased levels of oxidative damage, but that increased levels of biliverdin would limit this increase. We found that even just visual exposure to a potential combatant resulted in decreased body mass during the subsequent 48-hour period, but that hematocrit, biliverdin concentration in the bile, relative spleen size, and oxidative damage in plasma, liver, and spleen were unaffected. Contrary to our predictions, we found that individuals with smaller spleens exhibited greater decreases in hematocrit and higher bile biliverdin concentrations, suggesting a revision to the idea of spleen-dependent erythrocyte processing. Interestingly, individuals with larger spleens had reduced oxidative damage in both the liver and spleen, demonstrating the spleen's importance in modulating oxidative damage. We also uncovered differences in spleen size and oxidative damage between wild and captive-bred chameleons, highlighting environmentally dependent differences in oxidative physiology. Lastly, we found no relationship between oxidative damage and biliverdin concentration, calling into question biliverdin's antioxidant role in this species.

  13. Colloid-facilitated metal transport in peat filters.

    Science.gov (United States)

    Kalmykova, Yuliya; Rauch, Sebastien; Strömvall, Ann-Margret; Morrison, Greg; Stolpe, Björn; Hasselliöv, Martin

    2010-06-01

    The effect of colloids on metal retention in peat columns was studied, with the focus on colloids from two sources-organic matter leached from peat, and introduced organic and hydrous ferric oxide (HFO) colloids. A significant fraction of metals was found to be associated with peat-produced organic colloids; however the concentrations of organic colloids leached are low (trace concentrations) and temporal and have a limited effect on the efficiency of peat filters. In contrast, the presence of organic and HFO colloids in the input water causes a significant decrease in the performance of peat filters. Organic colloids were identified as the main vector of cadmium, copper, nickel, and zinc, while lead is transported by both organic and HFO colloids. The colloidal distribution of metals obtained in this study has important implications for the mobility of trace metals in porous media. The occurrence of colloids in the input waters and their characteristics must be considered when designing water treatment facilities.

  14. Carbon Nanomaterials as Antibacterial Colloids

    Directory of Open Access Journals (Sweden)

    Michael Maas

    2016-07-01

    Full Text Available Carbon nanomaterials like graphene, carbon nanotubes, fullerenes and the various forms of diamond have attracted great attention for their vast potential regarding applications in electrical engineering and as biomaterials. The study of the antibacterial properties of carbon nanomaterials provides fundamental information on the possible toxicity and environmental impact of these materials. Furthermore, as a result of the increasing prevalence of resistant bacteria strains, the development of novel antibacterial materials is of great importance. This article reviews current research efforts on characterizing the antibacterial activity of carbon nanomaterials from the perspective of colloid and interface science. Building on these fundamental findings, recent functionalization strategies for enhancing the antibacterial effect of carbon nanomaterials are described. The review concludes with a comprehensive outlook that summarizes the most important discoveries and trends regarding antibacterial carbon nanomaterials.

  15. Colloidal QDs-polymer nanocomposites

    Science.gov (United States)

    Gordillo, H.; Suárez, I.; Rodríguez-Cantó, P.; Abargues, R.; García-Calzada, R.; Chyrvony, V.; Albert, S.; Martínez-Pastor, J.

    2012-04-01

    Nanometer-size colloidal semiconductor nanocrystals, or Quantum Dots (NQD), are very prospective active centers because their light emission is highly efficient and temperature-independent. Nanocomposites based on the incorporation of QDs inside a polymer matrix are very promising materials for application in future photonic devices because they combine the properties of QDs with the technological feasibility of polymers. In the present work some basic applications of these new materials have been studied. Firstly, the fabrication of planar and linear waveguides based on the incorporation of CdS, CdSe and CdTe in PMMA and SU-8 are demonstrated. As a result, photoluminescence (PL) of the QDs are coupled to a waveguide mode, being it able to obtain multicolor waveguiding. Secondly, nanocomposite films have been evaluated as photon energy down-shifting converters to improve the efficiency of solar cells.

  16. Cracking in Drying Colloidal Films

    Science.gov (United States)

    Singh, Karnail B.; Tirumkudulu, Mahesh S.

    2007-05-01

    It has long been known that thick films of colloidal dispersions such as wet clays, paints, and coatings crack under drying. Although capillary stresses generated during drying have been recently identified as the cause for cracking, the existence of a maximum crack-free film thickness that depends on particle size, rigidity, and packing has not been understood. Here, we identify two distinct regimes for crack-free films based on the magnitude of compressive strain at the maximum attainable capillary pressure and show remarkable agreement of measurements with our theory. We anticipate our results to not only form the basis for design of coating formulations for the paints, coatings, and ceramics industry but also assist in the production of crack-free photonic band gap crystals.

  17. Optimizing colloidal nanocrystals for applications

    International Nuclear Information System (INIS)

    Sytnyk, M.

    2015-01-01

    In the scientific literature colloidal nanocrystals are presented as promising materials for multiple applications, in areas covering optoelectronics, photovoltaics, spintronics, catalysis, and bio-medicine. On the marked are, however, only a very limited number of examples found, indeed implementing colloidal nanocrystals. Thus the scope of this thesis was to modify nanocrystals and to tune their properties to fulfill specific demands. While some modifications could be achieved by post synthetic treatments, one key problem of colloidal nanocrystals, hampering there widespread application is the toxicity of their constituents. To develop nanocrystals from non-toxic materials has been a major goal of this thesis as well. Roughly, the results in this thesis could be subdivided into three parts: (i) the development of ion exchange methods to tailor the properties of metallic and metal-oxide based nanocrystal heterostructures, (ii), the synthesis of semiconductor nanocrystals from non-toxic materials, and (iii) the characterization of the nanocrystals by measurements of their morphology, chemical composition, magnetic-, optical-, and electronic properties. In detail, the thesis is subdivided into an introductory chapter, 4 chapters reporting on scientific results, a chapter reporting the used methods, and the conclusions. The 4 chapters devoted to the scientific results correspond to manuscripts, which are either currently in preparation, or have been published in highly ranked scientific journals such as NanoLetters (chapter 2), ACS Nano (chapter 4), or JACS (chapter 5). Thus, these chapters provide also an extra introduction and conclusion section, as well as separate reference lists. Chapter 2 describes a cation exchange process which is used to tune and improve the magnetic properties of different iron-oxide based colloidal nanocrystal-heterostructures. The superparamagnetic blocking temperature, magnetic remanence, and coercivity is tuned by replacing Fe2+ by Co2

  18. A Study on the Significance of the Colloidal Radiogold Disappearance Rate as a Simple Clinical Liver Function Test

    International Nuclear Information System (INIS)

    Hong, Chang Gi

    1969-01-01

    Liver function in diffuse parenchymal liver such as cirrhosis of the liver depend largely on the effective hepatic blood flow rather than on the individual cell functions. Clinical methods of measuring the hepatic blood flow were developed recently by the application of colloidal disappearance rate. In order to correlate the radiogold disappearance rate to conventional biochemical liver function tests, 21 normal subjects and 80 cases of cirrhosis of the liver were studied with both methods. The results are summarized as following: 1) The validity of external counting method to measure the blood disappearance rate of colloidal radiogold was confirmed by in vitro counting of the serial blood samples. 2) The blood disappearance rate of colloidal radiogold was essentially the same as the liver uptake rate of colloidal radiogold in normal and cirrhotic subjects with various degrees of functional disturbance. And it seemed there was no serious extrahepatic removal of the colloidal radiogold. 3) The disappearance rate of colloidal radiogold was not significant changed by the posture change, but was enhanced by ingestion of 500 ml of water. 4) The disappearance rate of colloidal radiogold was not influenced y single dose of Telepaque, while BSP retention was increased after Telepaque. 5) The mean disappearance half time of colloidal radiogold in normal subjects was 2.49±0.391 (S.D.) minutes. The mean normal disappearance rate constant (K value) was 0.285±0.0428 (S.D.)/minute. 6) The colloidal radiogold disappearance half time was abnormally prolonged (over 3.2 mm) in 87.7±3.68 (S.D.) % of cirrhotic subjects. 7) In patients of liver cirrhosis the blood disappearance rate of colloidal radiogold correlated well to serum albumin and globulin levels and BSP retention which were considered to reflect functions of hepatic parenchymal cells. There was, however, no correlation between colloidal disappearance rate and thymol turbidity test, serum glutamic pyruvic transaminase

  19. Effect of desorption kinetics on colloid-facilitated transport of contaminants: Cesium, strontium, and illite colloids

    Science.gov (United States)

    Turner, Ned B.; Ryan, Joseph N.; Saiers, James E.

    2006-12-01

    To examine the importance of desorption kinetics to colloid-facilitated transport, we conducted column experiments comparing the transport of cesium and strontium through a saturated quartz sand porous medium in the absence and presence of illite colloids at two ionic strengths. Because cesium desorption from illite was anticipated to be slower than that of strontium, we expected to see a contrast in the colloid-facilitated transport of the cations. A model of colloid-facilitated transport accounting for second-order cation adsorption to and desorption from the quartz, second-order cation adsorption to and desorption from fast and slow sites on the illite colloids, and second-order colloid deposition to and release from the quartz accurately simulated the cation transport in the absence and presence of the illite colloids. The column results and model simulations revealed that cesium desorption was indeed slower than strontium desorption and that this contrast in desorption kinetics resulted in greater colloid-facilitated transport of the cesium. The desorption of both cations was slow relative to the rate of advection. The fast and slow sites on the illite colloids behaved like planar and frayed edge sites typically identified for cesium adsorption to illite. The amount of cesium adsorbed to the slow, or frayed edge, sites was similar to the frayed edge site density of illite estimated by other researchers.

  20. Linear Optical Properties of Gold Colloid

    Directory of Open Access Journals (Sweden)

    Jingmin XIA

    2015-11-01

    Full Text Available Gold colloid was prepared by reducing HAuCl4·4H2O with Na3C6H5O7·2H2O. The morphology, size of gold nanoparticles and the optical property of colloid were characterized by transmission electron microscope and UV-Vis spectrophotometer, respectively. It shows that the gold nanoparticles are in the shape of spheres with diameters less than 8 nm, and the surface plasmon resonance absorption peak is located at about 438 nm. As the volume fraction of gold particles increases, the intensity of absorption peak strengthens. The optical property of gold colloid was analyzed by Maxwell-Garnett (MG effective medium theory in the company of Drude dispersion model. The results show that the matrix dielectric constant is a main factor, which influences the optical property of gold colloid.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9558

  1. Colloidal Mineral Liquid Crystals. Formation & Manipulation

    NARCIS (Netherlands)

    Leferink op Reinink, A.B.G.M.

    2014-01-01

    The central topic of this thesis is the formation, manipulation and characterization of colloidal mineral liquid crystals. Liquid crystals are liquids containing ordered anisometric particles. A range of liquid crystalline phases exists, from solely orientationally ordered nematic phases to

  2. Hemorrhagic Colloid Cyst Presenting with Acute Hydrocephaly

    Directory of Open Access Journals (Sweden)

    Reza Akhavan

    2017-01-01

    Full Text Available Colloid cysts are benign slow-growing cystic lesions located on the roof of the third ventricle that usually present with symptoms related to gradual rise of intracranial pressure. They mostly remain asymptomatic and sometimes grow progressively and cause diverse symptoms associated with increased intracranial pressure such as headache, diplopia, and sixth cranial nerve palsy. Here we report a 47-year-old female who presented to the emergency department with acute severe headache and nausea/vomiting. On MRI examination acute hydrocephaly due to hemorrhagic colloid cyst was detected. Acute hemorrhage in colloid cysts is extremely rare and may present with symptoms of acute increase in the intracranial pressure. Intracystic hemorrhage is very rarely reported as a complication of colloid cyst presenting with paroxysmal symptoms of acute hydrocephaly.

  3. Suspensions of colloidal particles and aggregates

    CERN Document Server

    Babick, Frank

    2016-01-01

    This book addresses the properties of particles in colloidal suspensions. It has a focus on particle aggregates and the dependency of their physical behaviour on morphological parameters. For this purpose, relevant theories and methodological tools are reviewed and applied to selected examples. The book is divided into four main chapters. The first of them introduces important measurement techniques for the determination of particle size and interfacial properties in colloidal suspensions. A further chapter is devoted to the physico-chemical properties of colloidal particles—highlighting the interfacial phenomena and the corresponding interactions between particles. The book’s central chapter examines the structure-property relations of colloidal aggregates. This comprises concepts to quantify size and structure of aggregates, models and numerical tools for calculating the (light) scattering and hydrodynamic properties of aggregates, and a discussion on van-der-Waals and double layer interactions between ...

  4. Size determinations of colloidal fat emulsions

    DEFF Research Database (Denmark)

    Kuntsche, Judith; Klaus, Katrin; Steiniger, Frank

    2009-01-01

    Size and size distributions of colloidal dispersions are of crucial importance for their performance and safety. In the present study, commercially available fat emulsions (Lipofundin N, Lipofundin MCT and Lipidem) were analyzed by photon correlation spectroscopy, laser diffraction with adequate ...

  5. Transformative Colloidal Nanomaterials for Mid- Infrared Devices

    Science.gov (United States)

    2015-06-11

    conductivity in monodispersed colloidal nanocrystal films was observed first nearly a decade ago, 7 field-effect transistors achieve ever increasing...mobilities,8 there are reports of high sensitivity photoconduction,9 and photovoltaic performance is improving with already ~100% quantum efficiency.2 The...446 (2005) [2] Hillhouse, H.W., Beard, M.C., “Solar cells from colloidal nanocrystals: Fundamentals, materials, devices, and economics,” Curr. Op

  6. Tunable Time-Dependent Colloidal Interactions

    Science.gov (United States)

    Bergman, Andrew M.; Rogers, W. Benjamin; Manoharan, Vinothan N.

    Self-assembly of colloidal particles can be driven by changes in temperature, density, or the concentration of solutes, and it is even possible to program the thermal response and equilibrium phase transitions of such systems. It is still difficult, however, to tune how the self-assembly process varies in time. We demonstrate control over the time-dependence of colloidal interactions, using DNA-functionalized colloidal particles with binding energies that are set by the concentration of a free linker strand in solution. We control the rate at which this free strand is consumed using a catalytic DNA reaction, whose rate is governed by the concentration of a catalyst strand. Varying the concentration of the linker, its competitor, and the catalyst at a fixed temperature, we can tune the rate and degree of the formation of colloidal aggregates and their following disassembly. Close to the colloidal melting point, the timescales of these out-of-equilibrium assembly and disassembly processes are determined by the rate of the catalytic reaction. Far below the colloidal melting point, however, the effects from varying our linker and competitor concentrations dominate.

  7. Inventions Utilizing Microfluidics and Colloidal Particles

    Science.gov (United States)

    Marr, David W.; Gong, Tieying; Oakey, John; Terray, Alexander V.; Wu, David T.

    2009-01-01

    Several related inventions pertain to families of devices that utilize microfluidics and/or colloidal particles to obtain useful physical effects. The families of devices can be summarized as follows: (1) Microfluidic pumps and/or valves wherein colloidal-size particles driven by electrical, magnetic, or optical fields serve as the principal moving parts that propel and/or direct the affected flows. (2) Devices that are similar to the aforementioned pumps and/or valves except that they are used to manipulate light instead of fluids. The colloidal particles in these devices are substantially constrained to move in a plane and are driven to spatially order them into arrays that function, variously, as waveguides, filters, or switches for optical signals. (3) Devices wherein the ultra-laminar nature of microfluidic flows is exploited to effect separation, sorting, or filtering of colloidal particles or biological cells in suspension. (4) Devices wherein a combination of confinement and applied electrical and/or optical fields forces the colloidal particles to become arranged into three-dimensional crystal lattices. Control of the colloidal crystalline structures could be exploited to control diffraction of light. (5) Microfluidic devices, incorporating fluid waveguides, wherein switching of flows among different paths would be accompanied by switching of optical signals.

  8. Spontaneous rupture of the spleen: A rare complication in a patient with lupus nephritis on hemodialysis

    Directory of Open Access Journals (Sweden)

    Nadri Quaid

    2010-01-01

    Full Text Available Rupture of the spleen is a life threatening condition. We report a 40-year-old fe-male patient, a known case of lupus nephritis receiving hemodialysis, who developed spontaneous rupture of the spleen during the course of her illness. The patient was managed conservatively with gradual regression of hematoma without further complications.

  9. Epithelial cyst of the spleen with squamous metaplasia: a rare entity.

    Science.gov (United States)

    Shanthi, Vissa; Reddy, Vengala Chidananda; Rao, Nandam Mohan; Grandhi, Bhavana; Kona, Suneetha

    2014-04-01

    Epithelial splenic cysts are uncommon lesions which occur the spleen. The aetiopathogenesis of these cysts is not clear. We are reporting a case of an epithelial cyst which occurred in the spleen in a 40-year-old female, which was multi loculated and which had flattened lining epithelium. Some foci showed squamous metaplasia.

  10. An epidermoid cyst of accessory spleen simulating tumors of the tail of pancreas

    Directory of Open Access Journals (Sweden)

    Amit Kumar Sinha

    2015-07-01

    Full Text Available An epidermoid cyst of accessory spleen, a rare condition may present as pseudocyst of pancreas and other cystic tumors of the pancreas. This case report along with the review of literature attributes some clinical features and investigative pattern to differentiate between epidermoid cyst of accessory spleen and other cystic tumor of pancreas.

  11. Two different mechanisms of immune-complex trapping in the mouse spleen during immune responses

    NARCIS (Netherlands)

    Yoshida, K.; van den Berg, T. K.; Dijkstra, C. D.

    1993-01-01

    The capacity of immune-complex (IC) trapping was examined using purified horse radish peroxidase (HRP)-anti-HRP (PAP) on frozen sections of mouse spleen in vitro. We investigated the trapping mechanisms by applying the IC with or without fresh mouse serum added on the spleen sections of naive as

  12. Late return of function after intrathoracic torsion of the spleen in congenital diaphragmatic hernia

    DEFF Research Database (Denmark)

    Thorup, Jørgen Mogens; Pedersen, P V

    1986-01-01

    , and the spleen were intrathoracic. There was a 720 degree torsion of the splenic pedicle. After reduction, the spleen was placed in the abdomen. At scintiscans 12 days and 14 weeks after operation, no certain splenic function was demonstrated, but at follow-up up 21/2 years later the splenic scan was normal....

  13. Accessory spleen presenting as acute abdomen: A case report and operative management

    Directory of Open Access Journals (Sweden)

    A. Landmann

    2016-09-01

    Full Text Available Accessory spleens are found in 10–30% of patients and are asymptomatic. Rarely, torsion of an accessory spleen can cause abdominal pain and acute abdomen. We present the case of an 8-year-old girl who arrives to the emergency room with left upper quadrant abdominal pain. CT scan revealed a non-enhancing soft tissue mass and multiple small splenules. Laparoscopy revealed a torsed accessory spleen and malrotation. Accessory spleen is a common congenital anomaly that is frequently asymptomatic. Rarely, an accessory spleen may become torsed around its vascular pedicle resulting in severe abdominal pain. Treatment is surgical resection. Torsion of accessory splenic tissue is a rare cause of acute abdomen in pediatric patients.

  14. Observation on Therapeutic Effect of the Depression of Heart-spleen Deficiency with Wuling Capsule

    International Nuclear Information System (INIS)

    Li Jinbin; Liu Ping

    2010-01-01

    To evaluate the effect on the treatment of depression belong to the type of heart-spleen deficiency with Wuling capsule, 37 patients were assigned into two groups: the deficiency of both the heart and spleen group (I) and the non deficiency of both the heart and spleen group (II). The efficacy of two groups was surveyed and compared after taken Wuling capsule 2 and 4 weeks,respectively. After treatment, there was a difference (P 0.05). The satisfactory effects were showed on various kinds of depressions using wuling capsules,while deficiency of both the heart and spleen group effects were better than that of the non deficiency of both the heart and spleen group. (authors)

  15. Increased numbers of spleen colony forming units in B cell deficient CBA/N mice

    International Nuclear Information System (INIS)

    Wiktor-Jedrzejczak, W.; Krupienicz, A.; Scher, I.

    1986-01-01

    The formation of exogenous and endogenous spleen colonies was studied in immune-defective mice expressing the CBA/N X-linked xid gene. Bone marrow and spleen cells of immune deficient mice formed increased numbers of eight-day exogenous spleen colonies when transferred to either normal or B cell deficient lethally irradiated recipients. Moreover, defective mice showed increased formation of five-day endogenous spleen colonies (derived from transient endogenous colony forming units; T-CFU) and of ten-day endogenous spleen colonies (derived from CFU-S). Among the possible mechanisms responsible for the observed effects, the most probable appears the one in which decreased numbers of B cell precursors stimulate stem cell pools through a feedback mechanism. (orig.) [de

  16. A case of torsion of the wandering spleen presenting as hypersplenism and gastric fundal varices.

    Science.gov (United States)

    Irak, Kader; Esen, Irfan; Keskın, Murat; Emınler, Ahmet Tarık; Ayyildiz, Talat; Kaya, Ekrem; Kiyici, Murat; Gürel, Selim; Nak, Selim Giray; Gülten, Macit; Dolar, Enver

    2011-02-01

    Wandering spleen is the displacement of the spleen from its normal location due to the loss or weakening of ligaments that hold the spleen in the left upper quadrant. The possibility of torsion of the spleen is high due to the long and mobile nature of the vascular pedicle. Generally, cases are asymptomatic. Under conditions of delayed diagnosis, symptoms of splenomegaly, left portal hypertension, gastric fundal varices, and hypersplenism may present as a result of development of vascular congestion associated with chronic torsion. There are only a few cases in the literature reporting the association of wandering spleen and fundal varices. We report herein the case of a 55-year-old female who admitted to our clinic with complaints of fatigue and epigastric pain. She was determined to have gastric fundal varices and hypersplenism secondary to the development of left portal hypertension due to chronic splenic torsion.

  17. Colloid-Facilitated Transport of Radionuclides Through The Vadose Zone

    International Nuclear Information System (INIS)

    Markus Flury; James B. Harsh; John F. McCarthy' Peter C. Lichtner; John M. Zachara

    2007-01-01

    The main purpose of this project was to advance the basic scientific understanding of colloid and colloid-facilitated Cs transport of radionuclides in the vadose zone. We focused our research on the hydrological and geochemical conditions beneath the leaking waste tanks at the USDOE Hanford reservation. Specific objectives were (1) to determine the lability and thermodynamic stability of colloidal materials, which form after reacting Hanford sediments with simulated Hanford Tank Waste, (2) to characterize the interactions between colloidal particles and contaminants, i.e., Cs and Eu, (3) to determine the potential of Hanford sediments for in situ mobilization of colloids, (4) to evaluate colloid-facilitated radionuclide transport through sediments under unsaturated flow, (5) to implement colloid-facilitated contaminant transport mechanisms into a transport model, and (6) to improve conceptual characterization of colloid-contaminant-soil interactions and colloid-facilitated transport for clean-up procedures and long-term risk assessment

  18. Preferences for colloid use in Scandinavian intensive care units

    DEFF Research Database (Denmark)

    Perner, A.; Aneman, A.; Guttormsen, A.B.

    2008-01-01

    trials of ICU patients showing changes in mortality or renal function, respectively. CONCLUSION: Most Scandinavian ICUs use both synthetic and natural colloids, but HES 130/0.4 is by far the preferred colloid. Few units have protocols for colloid use, but most use them for hypovolaemia, and the majority......BACKGROUND: Fluid resuscitation is a frequent intervention in intensive care. Colloids are widely used, but recent data suggest harm by some of these solutions. This calls for more clinical studies on this matter, but the current preferences for colloid use in Scandinavian intensive care units...... the questionnaire. Most ICUs used both synthetic and natural colloids, and hydroxyethyl starch (HES) 130/0.4 was the preferred colloid in 59 units. Eleven ICUs had protocols for colloid use. The most frequent indication was second-line fluid for hypovolaemia, but one in three ICUs used colloids as first-line fluid...

  19. The 2010 patent landscape for spleen tyrosine kinase inhibitors.

    Science.gov (United States)

    Moretto, Alessandro F; Dehnhardt, Christoph; Kaila, Neelu; Papaioannou, Nikolaos; Thorarensen, Atli

    2012-05-01

    Discovery of small molecular inhibitors for treatment of rheumatoid arthritis is a major ongoing effort within the pharmaceutical industry. Spleen tyrosine kinase (SYK) is one of leading small molecular targets with regard to clinical development primarlly due to efforts by Rigel and Portola. In this review, we provide a comprehensive overview of the SYK patent landscape. The patent literature we evaluated relates to any organization that has filed applications that imply that SYK is the intended target. The interest in SYK was initiated in the early 2000's with many organizations, including several large pharmaceutical companies, and has been active for years. In general, the structural theme of most of the compounds in these applications is a traditional ATP competitive inhibitor with each organization having a different hinge binding element. In general, the attachment to the hinge is an aryl amine that is decorated with a solubilizing group. The other substituents are broadly variable across the numerous companies indicating that SYK has significant flexibility in its interactions in that portion of the kinase. This overview of the SYK patent literature and the learnings of the inhibitors' substitution patterns would be an important reference for anyone working in this area.

  20. In vivo biodegradation of colloidal quantum dots by a freshwater invertebrate, Daphnia magna

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Dongwook; Kim, Min Jung; Park, Chansik; Park, Jaehong [Department of Chemistry, Hanyang University, Seoul 133-791 (Korea, Republic of); Choi, Kyungho [Department of Environmental Health, Seoul National University, Seoul 151-742 (Korea, Republic of); Yoon, Tae Hyun, E-mail: thyoon@gmail.com [Department of Chemistry, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2012-06-15

    Impacts of planktonic invertebrate, Daphnia magna, on the speciation of colloidal quantum dots (QD) were investigated using fluorescence spectromicroscopic technique. Well-dispersed {sup GA/TOPO}QD were prepared by forming a supramolecular assembly of hydrophobic {sup TOPO}QD with biomacromolecules (i.e., Gum Arabic, GA). Biological degradation of this nanomaterial was monitored by fluorescence spectromicroscopic methods. Our study confirmed the major uptake pathway of manufactured nanomaterials and in vivo biodegradation processes in a well-known toxicity test organism, D. magna. In addition, we also found that D. magna can induce significant deterioration of aquatic media by releasing fragments of partially degraded QD colloids. These biological processes may significantly change the predicted toxicities of nanomaterials in aquatic environments. Thus, we propose that the impacts of aquatic living organisms on the environmental fate of manufactured nanomaterials (MNs) should be carefully taken into account when assessing the risk of MNs to the environment and human health.

  1. Effect of Breath Holding on Spleen Volume Measured by Magnetic Resonance Imaging.

    Science.gov (United States)

    Inoue, Yusuke; Nakajima, Ai; Mizukami, Shinya; Hata, Hirofumi

    2013-01-01

    Ultrasonographic studies have demonstrated transient reduction in spleen volume in relation to apnea diving. We measured spleen volume under various respiratory conditions by MR imaging to accurately determine the influence of ordinary breath holding on spleen volumetry. Twelve healthy adult volunteers were examined. Contiguous MR images of the spleen were acquired during free breathing and during respiratory manipulations, including breath holding at the end of normal expiration, breath holding at deep inspiration, and the valsalva maneuver, and spleen volume was measured from each image set based on the sum-of-areas method. Acquisition during free breathing was performed with respiratory triggering. The duration of each respiratory manipulation was 30 s, and five sets of MR images were acquired serially during each manipulation. Baseline spleen volume before respiratory manipulation was 173.0 ± 79.7 mL, and the coefficient of variance for two baseline measures was 1.4% ± 1.6%, suggesting excellent repeatability. Spleen volume decreased significantly just after the commencement of respiratory manipulation, remained constant during the manipulation, and returned to the control value 2 min after the cessation of the manipulation, irrespective of manipulation type. The percentages of volume reduction were 10.2% ± 2.9%, 10.2% ± 3.5%, and 13.3% ± 5.7% during expiration breath holding, deep-inspiration breath holding, and the valsalva maneuver, respectively, and these values did not differ significantly. Spleen volume is reduced during short breath-hold apnea in healthy adults. Physiological responses of the spleen to respiratory manipulations should be considered in the measurement and interpretation of spleen volume.

  2. Spleen histology in children with sickle cell disease and hereditary spherocytosis: hints on the disease pathophysiology.

    Science.gov (United States)

    Pizzi, Marco; Fuligni, Fabio; Santoro, Luisa; Sabattini, Elena; Ichino, Martina; De Vito, Rita; Zucchetta, Pietro; Colombatti, Raffaella; Sainati, Laura; Gamba, Piergiorgio; Alaggio, Rita

    2017-02-01

    Hereditary spherocytosis (HS) and sickle cell disease (SCD) are associated with splenomegaly and spleen dysfunction in pediatric patients. Scant data exist on possible correlations between spleen morphology and function in HS and SCD. This study aimed to assess the histologic and morphometric features of HS and SCD spleens, to get possible correlations with disease pathophysiology. In a large series of spleens from SCD, HS, and control patients, the following parameters were considered: (i) macroscopic features, (ii) lymphoid follicle (LF) density, (iii) presence of perifollicular marginal zones, (iv) presence of Gamna-Gandy bodies, (v) density of CD8-positive sinusoids, (vi) density of CD34-positive microvessels, (vii) presence/distribution of fibrosis and smooth muscle actin (SMA)-positive myoid cells, and (viii) density of CD68-positive macrophages. SCD and HS spleens had similar macroscopic features. SCD spleens had lower LF density and fewer marginal zones than did HS spleens and controls. SCD also showed lower CD8-positive sinusoid density, increased CD34-positive microvessel density and SMA-positive myoid cells, and higher prevalence of fibrosis and Gamna-Gandy bodies. HS had lower LF and CD8-positive sinusoid density than did controls. No significant differences were noted in red pulp macrophages. By multivariate analysis, most HS spleens clustered with controls, whereas SCD grouped separately. A multiparametric score could predict the degree of spleen changes irrespective of the underlying disease. In conclusion, SCD spleens display greater histologic effacement than HS, and SCD-related changes suggest impaired function due to vascular damage. These observations may contribute to guide the clinical management of patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Colloidal Gelation-2 and Colloidal Disorder-Order Transition-2 Investigations Conducted on STS-95

    Science.gov (United States)

    Hoffmann, Monica T.

    2000-01-01

    The Colloidal Gelation-2 (CGEL 2) and Colloidal Disorder-Order Transition-2 (CDOT 2) investigations flew on Space Shuttle Discovery mission STS-95 (also known as the John Glenn Mission). These investigations were part of a series of colloid experiments designed to help scientists answer fundamental science questions and reduce the trial and error involved in developing new and better materials. Industries dealing with semiconductors, electro-optics, ceramics, and composites are just a few that may benefit from this knowledge. The goal of the CGEL 2 investigation was to study the fundamental properties of colloids to help scientists better understand their nature and make them more useful for technology. Colloids consist of very small (submicron) particles suspended in a fluid. They play a critical role in the technology of this country, finding uses in materials ranging from paints and coatings to drugs, cosmetics, food, and drink. Although these products are routinely produced and used, there are still many aspects of their behavior about which scientists know little. Understanding their structures may allow scientists to manipulate the physical properties of colloids (a process called "colloidal engineering") to produce new materials and products. Colloid research may even improve the processing of known products to enhance their desirable properties.

  4. Dynamic of Faceted Colloidal Clusters

    Science.gov (United States)

    Sindoro, Melinda; Jee, Ah-Young; Yu, Changqian; Granick, Steve

    2014-03-01

    We study the emulsion induced clustering of faceted metal organic frameworks (MOFs) and their dynamics. Our approach to anisotropic building block is through the rational synthesis of water stable and highly uniform MOFs. This generates colloidal-sized MOFs of defined polyhedral shape with tunable size in micrometer range that are suitable for in situ imaging. The 3D clusters formations are promoted by hydrophilic MOFs particles confined in aqueous droplets of binary water-lutidine mixture at transition temperature. Below this temperature, the water droplet decreases in volume due to one phase mixing with lutidine which forces the N-mers of faceted particles to aggregate in close contact. We compare the faceted clusters formed to those made of spherical particles in term of the building block sphericity. Other focus of our study involves the dynamic of the clusters. We found that, unlike spherical clusters, these faceted N-mers are highly stable on large scale of temperature due to their dominant capillary force on their facet-to-facet contact.

  5. Molecular Recognition in the Colloidal World.

    Science.gov (United States)

    Elacqua, Elizabeth; Zheng, Xiaolong; Shillingford, Cicely; Liu, Mingzhu; Weck, Marcus

    2017-11-21

    Colloidal self-assembly is a bottom-up technique to fabricate functional nanomaterials, with paramount interest stemming from programmable assembly of smaller building blocks into dynamic crystalline domains and photonic materials. Multiple established colloidal platforms feature diverse shapes and bonding interactions, while achieving specific orientations along with short- and long-range order. A major impediment to their universal use as building blocks for predesigned architectures is the inability to precisely dictate and control particle functionalization and concomitant reversible self-assembly. Progress in colloidal self-assembly necessitates the development of strategies that endow bonding specificity and directionality within assemblies. Methodologies that emulate molecular and polymeric three-dimensional (3D) architectures feature elements of covalent bonding, while high-fidelity molecular recognition events have been installed to realize responsive reconfigurable assemblies. The emergence of anisotropic 'colloidal molecules', coupled with the ability to site-specifically decorate particle surfaces with supramolecular recognition motifs, has facilitated the formation of superstructures via directional interactions and shape recognition. In this Account, we describe supramolecular assembly routes to drive colloidal particles into precisely assembled architectures or crystalline lattices via directional noncovalent molecular interactions. The design principles are based upon the fabrication of colloidal particles bearing surface-exposed functional groups that can undergo programmable conjugation to install recognition motifs with high fidelity. Modular and versatile by design, our strategy allows for the introduction and integration of molecular recognition principles into the colloidal world. We define noncovalent molecular interactions as site-specific forces that are predictable (i.e., feature selective and controllable complementary bonding partners

  6. Study on the pathological basis of classification of spleen deficiency in chronic gastritis.

    Science.gov (United States)

    Yin, Guang-yao; Zhang, Wu-ning; Shen, Xiao-jing; He, Xue-fen; Chen, Yi

    2004-08-01

    Spleen in Traditional Chinese Medicine (TCM) is not actually the spleen in the anatomic sense designated in western medicine because its functions basically belong to the physiological category of digestive system in modern medicine, and it represents a macroscopic concept of digestion, absorption and nutrition metabolism. Spleen deficiency syndrome refers to the clinical phenomena such as hypofunction of digestion, absorption and nutrition metabolism. By integrating TCM with modern medicine, this paper is intended to explore the pathological basis of classification of spleen deficiency in chronic gastritis. By means of optical microscope, scanning electron microscope (SEM), transmission electron microscope (TEM) and histochemical staining, we conducted histopathological and subcellular ultrastructural (nuclei and mitochondrial) analysis of gastric mucosa of 188 patients of spleen deficiency, and that of 42 voluntary blood donors without clinical symptoms. The gastric mucosa of patients with spleen Qi deficiency (SQD) and spleen yang deficiency (SyangD) could either be affected by organic lesion (type G-occurring on the basis of chronic superficial gastritis (CSG), chronic atrophic gastritis (CAG)) or unaffected (type F-chiefly belonging to functional indigestion); spleen yin deficiency (SyinD) and spleen deficiency with Qi stagnation (SDQS) both occurred on the basis of CSG and CAG; and the degree of mucosa inflammatory cells infiltration, the degree of decrease in glands propria, and the incidence of IMIIb in CSG and CAG were more serious than those of G-SQD and G-SyangD, P < 0.05 - 0.01. Spleen deficiency syndrome is likely to occur on the basis of organic lesion of gastric mucosa (disease with symptoms of both CSG or CAG and spleen deficiency symptoms), as well as on the basis of inorganic lesion of gastric mucosa (nondisease with symptoms, which is, despite spleen deficiency symptoms, there is no CSG or CAG). Besides, the clinical phenomenon of disease without

  7. Review on subsurface colloids and colloid-associated contaminant transport in saturated porous media.

    Science.gov (United States)

    Kanti Sen, Tushar; Khilar, Kartic C

    2006-02-28

    In this review article, the authors present up-to-date developments on experimental, modeling and field studies on the role of subsurface colloidal fines on contaminant transport in saturated porous media. It is a complex phenomenon in porous media involving several basic processes such as colloidal fines release, dispersion stabilization, migration and fines entrapment/plugging at the pore constrictions and adsorption at solid/liquid interface. The effects of these basic processes on the contaminant transport have been compiled. Here the authors first present the compilation on in situ colloidal fines sources, release, stabilization of colloidal dispersion and migration which are a function of physical and chemical conditions of subsurface environment and finally their role in inorganic and organic contaminants transport in porous media. The important aspects of this article are as follows: (i) it gives not only complete compilation on colloidal fines-facilitated contaminant transport but also reviews the new role of colloidal fines in contaminant retardation due to plugging of pore constrictions. This plugging phenomenon also depends on various factors such as concentration of colloidal fines, superficial velocity and bead-to-particle size ratio. This plugging-based contaminant transport can be used to develop containment technique in soil and groundwater remediation. (ii) It also presents the importance of critical salt concentration (CSC), critical ionic strength for mixed salt, critical shear stressor critical particle concentration (CPC) on in situ colloidal fines release and migration and consequently their role on contaminant transport in porous media. (iii) It also reviews another class of colloidal fines called biocolloids and their transport in porous media. Finally, the authors highlight the future research based on their critical review on colloid-associated contaminant transport in saturated porous media.

  8. Tl-201 per rectum scintigraphy in chronic liver disease: assessment of Tl-201 uptake indices

    International Nuclear Information System (INIS)

    Moon, Won Jin; Choi, Yun Young; Cho, Suk Shin; Lee, Min Ho

    1999-01-01

    Heart to liver ratio on Tl-201 per rectal scintigraphy (shunt index) is known to be useful in the assessment of portal systemic shunt. We assessed Tl-201 uptake pattern and early liver/heart uptake rate of Tl-201 and correlated with shunt index in patients with chronic active hepatitis (CAH) and liver cirrhosis (LC). Fifty eight patients with biopsy-proven chronic liver disease (35 with CAH, 23 with LC) underwent Tl-201 per rectum scintigraphy after instillation of 18.5 MBq of Tl-201 into the upper rectum. We evaluated hepatic uptake (type 1: homogeneous, 2: inhomogeneous segmental, 3: inhomogeneous nonsegmental) and extrahepatic uptake of spleen, heart and kidney (grade 0: no uptake, 1: less than liver, 2: equal to liver, 3: greater than liver). We measured the early liver/heart uptake rate (the slope of the liver to heart uptake ratio for 10 mim) and shunt index (heart to liver uptake ratio). Tl-201 uptake pattern and early liver/heart uptake rate of Tl-201 was correlated with the pathologic diagnosis and shunt index. Hepatic uptake patterns of type 1 and 2 were dominant in CAH (CAH: 27/35, LC: 8/23), and type 3 in LC (CAH: 8/35, LC: 15/23)(p<0.005). The grades of extrahepatic uptake were higher in LC than in CAH (spleen: p<0.001, other soft tissue: p<0.005). The early liver/heart uptake rate of CAH (0.110±0.111) was significantly higher than that of LC (0.014±0.090)(p<0.001). The sensitivity and specificity of the early liver/heart uptake rate were 77.7% and 67.7% in differentiating LC from CAH. There was negative correlation between early liver/heart uptake rate and shunt index (r=-0.3347, p<0.01). Hepatic and extrahepatic uptake pattern and early liver/heart uptake rate on Tl-201 per rectum scintigraphy are useful in the assessment of portal systemic shunt in patients with chronic liver disease

  9. Phosphoprotein phosphatase of bovine spleen cell nuclei: physicochemical properties

    International Nuclear Information System (INIS)

    Rezyapkin, V.I.; Leonova, L.E.; Komkova, A.I.

    1986-01-01

    The physicochemical properties of phosphoprotein phosphatase (EC 1.3.1.16) from bovine spleen cell nuclei were studied. The enzyme possesses broad substrate specificity and catalyzes the dephosphorylation of phosphocasein, ATP, ADP, and p-nitrophenyl phosphate (pNPP). K/sub m/ for ATP, ADP, and pNPP are equal to 0.44, 0.43, and 1.25 mM, respectively. M/sub r/ of the enzyme, according to the data of gel filtraction of Sephadex G-75 and electrophoresis in polyacrylamide gel of various concentrations is ∼ 33,000. In electrophoresis in the presence of SDS, two protein bands with M/sub r/ 12,000 and 18,000 are detected. In the enzyme molecule, acid amino acid residues predominate; two free SH groups and two disulfide bridges are detected. Phosphoprotein phosphatase is a glycoprotein, containing ∼ 22% carbonhydrates. The protein possesses a supplementary absorption maximum at 560 nm. Ammonium molybdate is a competitive inhibitor with K/sub i/ 0.37 μM, while sodium fluoride is a noncompetitive inhibitor with K/sub i/ 1.3 mM. Incubation in the presence of 2 mM phenylmethylsulfonyl fluoride for 25 h leads to a loss of ∼ 46% of the enzymatic activity. Ammonium molybdate, sodium fluoride, and PMSF are reversible inhibitors. Modifications of the SH groups, NH 2 groups, and histidine leads to a decrease in the enzymatic activity. Incubation of phosphoprotein phosphatase with [γ- 32 P]ATP leads to the incorporation of 0.33 mole 33 P per mole of the enzyme. The mechanism of hydrolysis of the phosphodiester bond, catalyzed by the enzyme, is discussed

  10. Which common test should be used to assess spleen autotransplant effect?

    Science.gov (United States)

    Soltani, Ehsan; Aliakbarian, Mohsen; Ghaffarzadegan, Kamran

    2018-01-01

    Historically, total splenectomy was the only choice of treatment for traumatic splenic injuries. However, nonoperative management and spleen-preserving surgical techniques are preferred in modern medicine. In some situations in which the surgeon has to perform splenectomy, spleen autotransplant may preserve the splenic function. Selecting the best method for evaluating the splenic autotransplant effect has been debated for several years. In this study, we compared three common tests in evaluating the implanted spleen function. Participants included 10 patients who were candidates for laparotomy and splenectomy. After performing splenectomy, we implanted five pieces of the spleen in the greater omentum of each patient. After 3 months, the implanted spleen function was evaluated by nuclear red blood cell (RBC) scan, serum immunoglobulin (Ig) M level, and presence of Howell-Jolly (HJ) bodies in the peripheral blood smear. All patients had normal peripheral blood smear. The IgM level was lower than normal in one patient, and scintigraphy did not demonstrate the transplanted spleen in another patient. All these tests may have comparable results, but because of availability and low cost of peripheral blood smear, which is also easily performed, it can be considered as the first option to evaluate the implanted spleen function.

  11. Microscopy of vascular architecture and arteriovenous communications in the spleen of two odontocetes.

    Science.gov (United States)

    Tanaka, Y

    1994-08-01

    The red pulp of the spleens of the short-finned pilot whale (Globicephala macrorhynchus) and the Pacific bottle-nosed dolphin (Tursiops truncatus gilli) (Odontoceti) were examined by light and electron microscopy and found to comprise two venous layers, an inner and an outer. The inner layer is homologous to the intermediate zone (IZ) of primitive-type mammalian spleens and contains sinusoids consisting of endothelial cells and a thin layer of extracellular deposits. Its vascular structure is unclear. The venous vessels of this layer eventually communicate with veins of the perivenous outer layer. The perivenous layer contains veins of various sizes, interstitial elements, and trabeculae. It is filled with blood cells, particularly plasma cells, but no myeloid cells. The perivenous layer (PVL) is homologous to the red pulp of common mammalian spleens but shows signs of involution. The white pulp gives origin to arterial terminals that end in the red pulp, where they communicate directly with the sinusoidal veins producing a closed circulation. The arterial terminals do not show ellipsoids. The presence of an IZ with a closed circulation and the involution of the red pulp makes the spleen of Odeontoceti another example of a mammalian spleen of the primitive type that has been altered by the evolutionary process. Vascular remodelling of the spleen of Odontoceti seems to follow the pattern noted in the spleens of nonmammalian vertebrates.

  12. The spleen is the site where mast cells are induced in the development of food allergy.

    Science.gov (United States)

    Toyoshima, Shota; Wakamatsu, Ei; Ishida, Yasuo; Obata, Yuuki; Kurashima, Yosuke; Kiyono, Hiroshi; Abe, Ryo

    2017-01-01

    It has been reported that splenic immune responses play pivotal roles in the development of allergic diseases; however, the precise role of the spleen remains unclear. Herein, we demonstrated a novel role of the spleen in the pathogenesis of food allergy (FA). We found that mast cells (MCs) developed from progenitor cells present in spleen during an antigen-specific T-cell response in vitro. In a Th2 response-mediated FA model, significant expansion of MCs was also observed in spleen. The incidence of allergic diarrhea was profoundly reduced in splenectomized mice, whereas adoptive transfer of in vitro-induced splenic MCs into these mice restored allergic symptoms, suggesting that the splenic MCs functioned as the pathogenic cells in the development of FA. The in vitro-generated MCs required not only IL-3 but also IFN-γ, and treatment of FA-induced mice with anti-IFN-γ antibody suppressed expansion of MCs in spleen as well as diarrhea development, highlighting that IFN-γ in the spleen orchestrated the development of FA, which was followed by a Th2 response in the local lesion. Overall, we propose that the role of the spleen in the development of FA is to provide a unique site where antigen-specific T cells induce development of pathogenic MCs. © The Japanese Society for Immunology. 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan and uptake uses ...

  14. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is also known as a thyroid uptake. ...

  15. Saturated Zone Colloid-Facilitated Transport

    International Nuclear Information System (INIS)

    Wolfsberg, A.; Reimus, P.

    2001-01-01

    The purpose of the Saturated Zone Colloid-Facilitated Transport Analysis and Modeling Report (AMR), as outlined in its Work Direction and Planning Document (CRWMS MandO 1999a), is to provide retardation factors for colloids with irreversibly-attached radionuclides, such as plutonium, in the saturated zone (SZ) between their point of entrance from the unsaturated zone (UZ) and downgradient compliance points. Although it is not exclusive to any particular radionuclide release scenario, this AMR especially addresses those scenarios pertaining to evidence from waste degradation experiments, which indicate that plutonium and perhaps other radionuclides may be irreversibly attached to colloids. This report establishes the requirements and elements of the design of a methodology for calculating colloid transport in the saturated zone at Yucca Mountain. In previous Total Systems Performance Assessment (TSPA) analyses, radionuclide-bearing colloids were assumed to be unretarded in their migration. Field experiments in fractured tuff at Yucca Mountain and in porous media at other sites indicate that colloids may, in fact, experience retardation relative to the mean pore-water velocity, suggesting that contaminants associated with colloids should also experience some retardation. Therefore, this analysis incorporates field data where available and a theoretical framework when site-specific data are not available for estimating plausible ranges of retardation factors in both saturated fractured tuff and saturated alluvium. The distribution of retardation factors for tuff and alluvium are developed in a form consistent with the Performance Assessment (PA) analysis framework for simulating radionuclide transport in the saturated zone. To improve on the work performed so far for the saturated-zone flow and transport modeling, concerted effort has been made in quantifying colloid retardation factors in both fractured tuff and alluvium. The fractured tuff analysis used recent data

  16. Single photon emission computed tomography and albumin colloid imaging of the liver

    International Nuclear Information System (INIS)

    Croft, B.Y.; Teates, C.D.; Honeyman, J.C.

    1984-01-01

    A single photon emission computed tomography (ECT) system using the GE 400T Anger camera with 37 PM tubes and the SPETS software has been installed in our clinical laboratory. It has been used in the study of liver imaging with Tc-99m albumin colloid and other agents. The object of the study is to define what improvement in liver diagnosis might be made using ECT. Patients were injected with 3-4 mCi (ca 120 MBq) of colloid; five standard liver-spleen views and a 64-image ECT study were acquired. The ECT images were acquired either in a circle of the radius of the longer transverse axis of the patient or in an ellipse to match the patient contour. Studies were corrected for the attenuation of the Tc-99m gamma rays by tissue. A series of normal and abnormal patients have been studied and the data analyzed. The significant change in the technique of ECT imaging is the elliptical motion of the camera head which allows a better approximation of the patient contour and improves the spatial resolution of the images. (orig.)

  17. Colloids with continuously tunable surface charge.

    Science.gov (United States)

    van Ravensteijn, Bas G P; Kegel, Willem K

    2014-09-09

    In this paper, we present a robust way to tune the surface potential of polystyrene colloids without changing the pH, ionic strength, etc. The colloids are composed of a cross-linked polystyrene core and a cross-linked vinylbenzyl chloride layer. Besides the chlorine groups, the particle surface contains sulfate/sulfonate groups (arising from the polymerization initiators) that provide a negative surface potential. Performing a Menschutkin reaction on the surface chlorine groups with tertiary amines allows us to introduce quaternary, positively charged amines. The overall charge on the particles is then determined by the ratio between the sulfate/sulfonate moieties and the quaternary amines. Using this process, we were able to invert the charge in a continuous manner without losing colloidal stability upon passing the isoelectric point. The straightforward reaction mechanism together with the fact that the reaction could be quenched rapidly resulted in a colloidal system in which the ζ potential can be tuned between -80 and 45 mV. As proof of principle, the positively charged particles were used in heterocoagulation experiments with nanometer- and micrometer-sized negatively charged silica particles to create geometrically well-defined colloidal (nano) clusters.

  18. Size Segregation in Sheared Jammed Colloids

    Science.gov (United States)

    Mbi, Armstrong; Blair, Daniel

    2013-03-01

    It is well known that granular materials can spontaneously size segregate when continuously driven. However, in jammed colloidal suspensions, this phenomenon is not well understood. Colloidal dispersions provide a unique system to study the structure and dynamics of jammed matter. In this talk, we present results of size segregation of a continuously sheared binary colloidal suspension well above point J. Our colloidal system is comprised of indexed-matched bi-disperse silica particles with diameters a = { 2 . 3 μm and 3 . 2 μm } and at ϕ 61 % , well above the colloidal glass transition. We apply a highly controlled shear at a constant shear rate through the use of a rheometer. By coupling our rheometer with a high-speed laser scanning confocal microscope, we directly image the structure and flow profiles of the suspension as it un-jams. We observe migration of the small and large species; large particles move to the top while the small particles move toward the bottom conserving the total volume fraction in all regions. Moreover, we find that an associating feature of segregation is a sustained shear band. Our results are consistent with a recently proposed void filling and squeeze expulsion mechanism. Funding is provided by NSF DMR #0847490.

  19. Sorption behavior of cesium onto bentonite colloid

    International Nuclear Information System (INIS)

    Iijima, Kazuki; Masuda, Tsuguya; Tomura, Tsutomu

    2004-01-01

    It is considered that bentonite colloid might be generated from bentonite which will be used as buffer material in geological disposal system, and can facilitate the migration of radionuclides by means of sorption. In order to examine this characteristic, sorption and desorption experiments of Cs onto bentonite colloid were carried out to obtain its distribution coefficient (Kd) and information on the reversibility of its sorption. In addition, particle size distribution and shape of colloid were investigated and their effect on the sorption behavior was discussed. Kds for Cs were around 20 m 3 /kg for sorption and 30 m 3 /kg for desorption, in which sorbed Cs was desorbed by 8.4x10 -4 mol/l of NaCl solution. These values did not show any dependencies on Cs concentration and duration of sorption and desorption. The first 20% of sorbed Cs was desorbed reversibly at least. Most of colloidal particles were larger than 200 nm and TEM micrographs showed they had only several sheets of the clay crystal. Obtained Kds for colloidal bentonite were larger than those for powdered bentonite. This can be caused by difference of competing ions in the solution, characteristics of contained smectite, or sorption site density. (author)

  20. Influence of particle shape on plasma protein adsorption and macrophage uptake.

    Science.gov (United States)

    Jansch, M; Jindal, A B; Sharmila, B Majee; Samad, A; Devarajan, P V; Müller, R H

    2013-01-01

    The purpose of this study was to evaluate the plasma protein adsorption behavior onto different LIPOMER nanoparticles, especially looking for the first time, if the particle shape affects the protein adsorption pattern. The potential in vivo fate is discussed and compared with previous in vivo animal studies. The two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) was used for identification of adsorbed plasma proteins. Qualitative similar patterns were obtained from the protein adsorption analysis and four apolipoproteins with considerable quantitative differences were identified. Besides the quantitative differences in the adsorbed apolipoproteins, in vitro uptake in the human macrophage cell line U-937 of histocytic lymphoma organ revealed significantly lower uptake of the irregular glycerol monostearate LIPOMER nanoparticles. Therefore, protein adsorption does not seem to play a role in the splenotropic behavior in the sense, that adsorption of opsonins, especially spleen-specific opsonins are required for the uptake. The splenotropic uptake might be favored because all LIPOMER nanoparticles did not adsorb opsonins at all, mediating competitive uptake by liver macrophages. Differences in the in vivo uptake by the spleen were attributed to differences in particle shape with potential super position effect by the quantitative differences in the adsorbed proteins.

  1. Release and retention of labelled DNA in the thymus and spleen of irradiated mice

    International Nuclear Information System (INIS)

    Suciu, D.; Uray, Z.; Abraham, A.D.

    1976-01-01

    The process of release and retention of labelled DNA in thymus and spleen of normal and irradiated ( 06 Co) mice has been studied after administration of 3 H-thymidine. The results indicate that the dividing fraction of lymphoid cells is more resistant to radiation than the fraction of nondividing lymphoytes. The time courses of the specific activities of DNA in thymus and spleen were different especially after irradiation with lethal doses. It is suggested that the process of depletion in the lymphoid series is probably similar for both thymus and spleen but, the different cellular composition of these organs led to apparently unrelated results. (orig.) [de

  2. Torsion of a wandering spleen. A rare cause of acute abdomen

    Directory of Open Access Journals (Sweden)

    Nwashilli N. Jude

    2015-12-01

    Full Text Available Wandering spleen is a rare condition that accounts for less than 0.25% of all indications for splenectomy. It is characterized by ectopic localization of the spleen owing to the lack or weakening of its ligaments. Torsion is the most common complication due to its long pedicle and high mobility, which may result in acute abdomen. We report a case of torsion in a wandering spleen in a 28-year-old male presenting with an acute abdomen that was treated by splenectomy.

  3. Active suppression of in vitro reactivity of spleen cells after BCG treatment

    International Nuclear Information System (INIS)

    Orbach-Arbouys, S.; Poupon, M.F.

    1978-01-01

    It was found that spleen cells from mice injected i.v. with large doses of BCG responded to PHA stimulation less intensely than did normal spleen cells. It was shown that nylon wool column purified BCG treated T cells also had a low PHA reactivity. Unfractionated spleen cells, adherent cells or T-enriched populations from BCG treated mice, when added to normal T cells lowered their PHA reactivity. When the same BCG treated cell populations were added to tumor cells in vitro, they inhibited their growth. (author)

  4. Knowledge of the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages.

    Science.gov (United States)

    Paraskevas, George K; Koutsouflianiotis, Konstantinos N; Nitsa, Zoi; Demesticha, Theano; Skandalakis, Panagiotis

    2016-01-01

    The evolution of knowledge regarding the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages is described, and general perceptions about this organ during different eras along this time line are presented. The original words of great physicians from the period of time stretching from Ancient Egypt to the Avicennan era are quoted and discussed to demonstrate how knowledge of the spleen has evolved and to present the theories that dominated each era. Furthermore, theories about illnesses relating to the spleen are reported, which show how this organ was perceived-in terms of its function and anatomy-during each era.

  5. Size matters: Spleen and lung volumes predict performance in human apneic diving

    Directory of Open Access Journals (Sweden)

    Erika eSchagatay

    2012-06-01

    Full Text Available Humans share with e.g. seals the ability to contract the spleen and increase circulating hematocrit, which may improve apneic performance by enhancing gas storage. Seals have large spleens and while human spleen size is small in comparison, it shows great individual variation. Unlike many marine mammals, human divers rely to a great extent on lung oxygen stores, but the impact of lung volume on competitive apnea performance has never been determined. We studied if spleen- and lung size correlated with performance in elite apnea divers. Volunteers were 14 male apnea world championship participants, with a mean(SE of 5.8(1.2 years of previous apnea training. Spleen volume was calculated from spleen length, width and thickness measured via ultrasound during rest, and vital capacity via spirometry. Accumulated competition scores from dives of maximal depth, time and distance were compared to anthropometric measurements and training data. Mean dive performance was 75(4 m for constant weight depth, 5 min 53(39 s for static apnea and 139(13 m for dynamic apnea distance. Subjects’ mean height was 184(2 cm, weight 82(3 kg, vital capacity (VC 7.3(0.3 L and spleen volume 336(32 ml. Spleen volume did not correlate with subject height or weight, but was positively correlated with competition score (r=0.57; P<0.05. Total competition score was also positively correlated with VC (r=0.54; P<0.05. The three highest scoring divers had the greatest spleen volumes, averaging 538(53 ml, while the three lowest scoring divers had a volume of 270(71 ml (P<0.01. VC was also greater in the high-scorers, at 7.9(0.36 L as compared to 6.7(0.19 L in the low-scorers (P<0.01. Spleen volume was reduced to half after 2 min of apnea in the highest scoring divers, and the estimated resting apnea time gain from the difference between high and low scorers was 15 s for spleen volume and 60 s for VC. We conclude that both spleen- and lung volume predict apnea performance in elite

  6. Computed tomography of the spleen and liver in sickle cell disease

    International Nuclear Information System (INIS)

    Magid, D.; Fishman, E.K.; Siegelman, S.S.

    1984-01-01

    The spleen was assessed in 10 patients with sickle cell disease studied with computed tomography (CT) for abdominal pain and/or unexplained fever. Patients with homozygous sickle cell anemia were found to have small, densely calcified spleens with occasional low-density infarcts. Five of six had hepatomegaly, and there was one case each of hepatic abscess, infarcts, and hemochromatosis. All patients with heterozygous sickle cell disease were found to have splenomegaly, with a variety of findings including acute hemorrhage, acute and chronic infarcts, rupture, and possible sequestration. It was concluded that CT is useful for evaluating the status of the spleen and liver in symptomatic patients with sickle cell disease

  7. Influence of heteroaggregation processes between intrinsic colloids and carrier colloids on cerium(III) mobility through fractured carbonate rocks.

    Science.gov (United States)

    Tran, Emily; Klein Ben-David, Ofra; Teutch, Nadya; Weisbrod, Noam

    2016-09-01

    Colloid facilitated transport of radionuclides has been implicated as a major transport vector for leaked nuclear waste in the subsurface. Sorption of radionuclides onto mobile carrier colloids such as bentonite and humic acid often accelerates their transport through saturated rock fractures. Here, we employ column studies to investigate the impact of intrinsic, bentonite and humic acid colloids on the transport and recovery of Ce(III) through a fractured chalk core. Ce(III) recovery where either bentonite or humic colloids were added was 7.7-26.9% Ce for all experiments. Greater Ce(III) recovery was observed when both types of carrier colloids were present (25.4-37.4%). When only bentonite colloids were present, Ce(III) appeared to be fractionated between chemical sorption to the bentonite colloid surfaces and heteroaggregation of bentonite colloids with intrinsic carbonate colloids, precipitated naturally in solution. However, scanning electron microscope (SEM) images and colloid stability experiments reveal that in suspensions of humic acid colloids, colloid-facilitated Ce(III) migration results only from the latter attachment mechanism rather than from chemical sorption. This observed heteroaggregation of different colloid types may be an important factor to consider when predicting potential mobility of leaked radionuclides from geological repositories for spent fuel located in carbonate rocks. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. A general approach for monodisperse colloidal perovskites, Chemistry of Materials

    NARCIS (Netherlands)

    Demirors, A.F.|info:eu-repo/dai/nl/30483176X; Imhof, A.|info:eu-repo/dai/nl/145641600

    2009-01-01

    We describe a novel general method for synthesizing monodisperse colloidal perovskite particles at room temperature by postsynthesis addition of metal hydroxides to amorphous titania colloids. In previous work, we used titania particles to synthesize homogenously mixed silica-titania composite

  9. Inorganic passivation and doping control in colloidal quantum dot photovoltaics

    KAUST Repository

    Hoogland, Sjoerd H.

    2012-01-01

    We discuss strategies to reduce midgap trap state densities in colloidal quantum dot films and requirements to control doping type and magnitude. We demonstrate that these improvements result in colloidal quantum dot solar cells with certified 7.0% efficiency.

  10. Colloid-templated multisectional porous polymeric fibers.

    Science.gov (United States)

    Song, Jung Hun; Kretzschmar, Ilona

    2008-10-07

    A fabrication method for porous polymeric fibers (PPFs) is reported. We show that a multisectional colloidal crystal can be assembled within a microcapillary by alternating dipping into colloidal solutions of varying size. Subsequent infiltration with curable polymer and washing with suitable solvents results in porous fibers with a cylindrical cross section. Along the length of the fiber, alternating sections of controlled length, pore size, and pore size distribution exist. These fibers present interesting materials for neural scaffolding, catalysis, and possibly photonics if produced with a high degree of crystallinity. The surface pores and bulk porosity of the fibers are characterized by variable-pressure scanning electron microscopy (vp-SEM). Careful analysis shows that the surface pores vary with the colloidal template diameter and polymer infiltration time.

  11. Vector assembly of colloids on monolayer substrates

    Science.gov (United States)

    Jiang, Lingxiang; Yang, Shenyu; Tsang, Boyce; Tu, Mei; Granick, Steve

    2017-06-01

    The key to spontaneous and directed assembly is to encode the desired assembly information to building blocks in a programmable and efficient way. In computer graphics, raster graphics encodes images on a single-pixel level, conferring fine details at the expense of large file sizes, whereas vector graphics encrypts shape information into vectors that allow small file sizes and operational transformations. Here, we adapt this raster/vector concept to a 2D colloidal system and realize `vector assembly' by manipulating particles on a colloidal monolayer substrate with optical tweezers. In contrast to raster assembly that assigns optical tweezers to each particle, vector assembly requires a minimal number of optical tweezers that allow operations like chain elongation and shortening. This vector approach enables simple uniform particles to form a vast collection of colloidal arenes and colloidenes, the spontaneous dissociation of which is achieved with precision and stage-by-stage complexity by simply removing the optical tweezers.

  12. Colloid and interface chemistry for nanotechnology

    CERN Document Server

    Kralchevsky, Peter; Ravera, Francesca

    2016-01-01

    Colloid and interface science dealt with nanoscale objects for nearly a century before the term nanotechnology was coined. An interdisciplinary field, it bridges the macroscopic world and the small world of atoms and molecules. Colloid and Interface Chemistry for Nanotechnology is a collection of manuscripts reflecting the activities of research teams that have been involved in the networking project Colloid and Interface Chemistry for Nanotechnology (2006-2011), Action D43, the European Science Foundation. The project was a part of the intergovernmental framework for Cooperation in Science and Technology (COST), allowing the coordination of nationally funded research across Europe. With contributions by leading experts, this book covers a wide range of topics. Chapters are grouped into three sections: "Nanoparticle Synthesis and Characterization," "New Experimental Tools and Interpretation," and "Nanocolloidal Dispersions and Interfaces." The topics covered belong to six basic research areas: (1) The synthes...

  13. Energy transport velocity in bidispersed magnetic colloids.

    Science.gov (United States)

    Bhatt, Hem; Patel, Rajesh; Mehta, R V

    2012-07-01

    Study of energy transport velocity of light is an effective background for slow, fast, and diffuse light and exhibits the photonic property of the material. We report a theoretical analysis of magnetic field dependent resonant behavior in forward-backward anisotropy factor, light diffusion constant, and energy transport velocity for bidispersed magnetic colloids. A bidispersed magnetic colloid is composed of micrometer size magnetic spheres dispersed in a magnetic nanofluid consisting of magnetic nanoparticles in a nonmagnetic liquid carrier. Magnetic Mie resonances and reduction in energy transport velocity accounts for the possible delay (longer dwell time) by field dependent resonant light transport. This resonant behavior of light in bidispersed magnetic colloids suggests a novel magnetophotonic material.

  14. THE CELLULAR TRANSFORMATION OF INJECTED COLLOIDAL IRON COMPLEXES INTO FERRITIN AND HEMOSIDERIN IN EXPERIMENTAL ANIMALS

    Science.gov (United States)

    Richter, Goetz W.

    1959-01-01

    As revealed by electron microscopy and electron diffraction, the physical state of ferric hydroxide micelles contained in iron-dextran, saccharated iron oxide, and hydrous ferric oxide ("ferric hydroxide") differs notably from the state of the ferric hydroxide in ferritin or hemosiderin. By virtue of this difference one can trace the intracellular transformation of colloidal iron, administered parenterally, into ferritin and hemosiderin. One hour after intraperitoneal injection of iron-dextran or saccharated iron oxide into mice, characteristic deposits were present in splenic macrophages, in sinusoidal endothelial cells of spleen and liver, and in vascular endothelial cells of various renal capillaries. Four hours after injection, small numbers of ferritin molecules were identifiable about intracellular aggregates of injected iron compounds; and by the 6th day, ferritin was abundant in close proximity to deposits of injected iron compounds. The latter were frequently situated in cytoplasmic vesicles delimited by single membranes. These vesicles were most frequently found in tissue obtained during the first 6 days after injection; and in certain of the vesicles ferritin molecules surrounded closely packed aggregates of injected material. Much unchanged ferric hydroxide was still present in macrophages and vascular endothelial cells 3 to 4 weeks after injection. While electron microscopy left no doubt about the identity of injected ferric hydroxide on the one hand, and of ferritin or hemosiderin on the other, histochemical tests for iron failed in this respect. Precipitation of ferric hydroxide (hydrous ferric oxide) from stabilized colloidal dispersions of iron-dextran was brought about in vitro by incubation with minced mouse tissue (e.g. liver), but not by incubation with mouse serum or blood. Subcutaneous injections of hydrous gel of ferric oxide into mice initially produced localized extracellular precipitates. Most of the material was still extracellular 16

  15. Colloid migration in groundwaters: Geochemical interactions of radionuclides with natural colloids. Final report

    International Nuclear Information System (INIS)

    Kim, J.J.; Longworth, G.; Hasler, S.E.; Gardiner, M.; Fritz, P.; Klotz, D.; Lazik, D.; Wolf, M.; Geyer, S.; Alexander, J.L.; Read, D.; Thomas, J.B.

    1994-08-01

    In this joint research programme the significance of groundwater colloids in far field radionuclide migration has been studied. The characterization, quantification and theoretical interpretation of colloid-borne transport phenomena for radionuclides were the main objectives of this research programme. Groundwaters, colloids and sediments were sampled from aquifer system overlying a saltdome in the Gorleben area in northern Germany and were characterized by various analytical methods (ICP-MS, ICP-AES, neutron activation analysis (NAA), DOC-Analyser, HPIC, potentiometric titration). Different natural isotopes ( 2 H, 3 H, 13 C, 14 C, 18 O, 34 S, U/Th decay series) were determined and their ratios were compared with one another in the order to ascertain the provenance of the groundwater colloids. The investigated groundwaters contain substantial amounts of colloids mainly composed of humic and fulvic acids loaded with various metal ions. The chemical interaction of radionuclide ions of various oxidation states (Am, Eu, for M(III), Th, Pu for M(IV), Np for M(V) and U for M(VI)) with groundwater colloids was investigated in order to elucidate the colloid facilitated migration behaviour of actinides in a given aquifer system. Transport process studies with generated pseudocolloids of radionuclides in various oxidation states were undertaken in scaled column experiments, pre-equilibrated with colloid rich Gorleben groundwater. A modelling programme was developed to predict chemical transport of radionuclides in the presence of humic colloids using a modified version of the CHEMTARD code. Modelling predictions have generated acceptable results for Eu, Am and U and poorer agreement between experimental and modelling results for Th and Np as a result of more limited data. (orig.)

  16. Colloid migration in groundwaters: Geochemical interactions of radionuclides with natural colloids. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.J. [Technische Univ. Muenchen, Garching (Germany). Inst. fuer Radiochemie; Delakowitz, B. [Technische Univ. Muenchen, Garching (Germany). Inst. fuer Radiochemie; Zeh, P. [Technische Univ. Muenchen, Garching (Germany). Inst. fuer Radiochemie; Probst, T. [Technische Univ. Muenchen, Garching (Germany). Inst. fuer Radiochemie; Lin, X. [Technische Univ. Muenchen, Garching (Germany). Inst. fuer Radiochemie; Ehrlicher, U. [Technische Univ. Muenchen, Garching (Germany). Inst. fuer Radiochemie; Schauer, C. [Technische Univ. Muenchen, Garching (Germany). Inst. fuer Radiochemie; Ivanovich, M. [AEA Environment and Energy, Harwell (United Kingdom); Longworth, G. [AEA Environment and Energy, Harwell (United Kingdom); Hasler, S.E. [AEA Environment and Energy, Harwell (United Kingdom); Gardiner, M. [AEA Decommissioning and Radwaste, Harwell (United Kingdom); Fritz, P. [Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany); Klotz, D. [Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany); Lazik, D. [Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany); Wolf, M. [Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany); Geyer, S. [Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany); Alexander, J.L. [Atkins (W.S.) Engineering Sciences, Epsom (United Kingdom); Read, D. [Atkins (W.S.) Engineering Sciences, Epsom (United Kingdom); Thomas, J.B. [Atkins (W.S.) Engineering Sciences, Epsom (United Kingdom)

    1994-08-01

    In this joint research programme the significance of groundwater colloids in far field radionuclide migration has been studied. The characterization, quantification and theoretical interpretation of colloid-borne transport phenomena for radionuclides were the main objectives of this research programme. Groundwaters, colloids and sediments were sampled from aquifer system overlying a saltdome in the Gorleben area in northern Germany and were characterized by various analytical methods (ICP-MS, ICP-AES, neutron activation analysis (NAA), DOC-Analyser, HPIC, potentiometric titration). Different natural isotopes ({sup 2}H, {sup 3}H, {sup 13}C, {sup 14}C, {sup 18}O, {sup 34}S, U/Th decay series) were determined and their ratios were compared with one another in the order to ascertain the provenance of the groundwater colloids. The investigated groundwaters contain substantial amounts of colloids mainly composed of humic and fulvic acids loaded with various metal ions. The chemical interaction of radionuclide ions of various oxidation states (Am, Eu, for M(III), Th, Pu for M(IV), Np for M(V) and U for M(VI)) with groundwater colloids was investigated in order to elucidate the colloid facilitated migration behaviour of actinides in a given aquifer system. Transport process studies with generated pseudocolloids of radionuclides in various oxidation states were undertaken in scaled column experiments, pre-equilibrated with colloid rich Gorleben groundwater. A modelling programme was developed to predict chemical transport of radionuclides in the presence of humic colloids using a modified version of the CHEMTARD code. Modelling predictions have generated acceptable results for Eu, Am and U and poorer agreement between experimental and modelling results for Th and Np as a result of more limited data. (orig.)

  17. Active structuring of colloidal armour on liquid drops

    OpenAIRE

    Dommersnes, Paul; Rozynek, Zbigniew; Mikkelsen, Alexander; Castberg, Rene; Kjerstad, Knut; Hersvik, Kjetil; Fossum, Jon Otto

    2013-01-01

    Adsorption and assembly of colloidal particles at the surface of liquid droplets are at the base of particle-stabilized emulsions and templating. Here we report that electrohydrodynamic and electro-rheological effects in leaky-dielectric liquid drops can be used to structure and dynamically control colloidal particle assemblies at drop surfaces, including electric-fieldassisted convective assembly of jammed colloidal ‘ribbons’, electro-rheological colloidal chains confined to a...

  18. Fatal Colloid Cysts: A Systematic Review.

    Science.gov (United States)

    Lagman, Carlito; Rai, Kanwaldeep; Chung, Lawrance K; Nagasawa, Daniel T; Beckett, Joel S; Tucker, Alexander M; Yang, Isaac

    2017-11-01

    To accurately describe patient characteristics and the clinical presentation of fatal colloid cysts. A systematic literature search of 3 popular databases was performed. Inclusion criteria were individuals with sudden-onset death and colloid cysts identified on imaging and/or autopsy. The cause of death must have been ascribed to the colloid cyst to be eligible for data extraction. Deaths precipitated by lumbar puncture were excluded. Clinical data were extracted and descriptive statistics were ascertained. Subgroup analyses were performed to compare adults with pediatric patients. A total of 107 patients were included in the quantitative synthesis. The mean age was 28.5 years (standard deviation 13.3, range 6-79 years). Male and female patients were affected equally. Headache was the most frequent symptom (n = 86, 80%). There were 6 patients (5 adults and 1 child) who reported positional headaches. The mean duration of signs and symptoms was shorter in adults versus pediatric patients (2.1 days vs. 6.5 days, P = 0.02), and more adults presented with signs and symptoms for less than 24 hours than did pediatric patients (38% vs. 6%, P = 0.01). Colloid cyst mean diameter was 2.0 cm (standard deviation 1.1, range 0.5-7.9 cm) and 96% measured 1 cm or larger. Our data suggests that the prodrome preceding sudden death in the setting of a colloid cyst may be shorter in adults. Also, most fatal colloid cysts measured 1 cm or larger. Copyright © 2017. Published by Elsevier Inc.

  19. Colloid straining within saturated heterogeneous porous media.

    Science.gov (United States)

    Porubcan, Alexis A; Xu, Shangping

    2011-02-01

    The transport of 0.46 μm, 2.94 μm, 5.1 μm and 6.06 μm latex particles in heterogeneous porous media prepared from the mixing of 0.78 mm, 0.46 mm and 0.23 mm quartz sands was investigated through column transport experiments. It was observed that the 0.46 μm particles traveled conservatively within the heterogeneous porous media, suggesting that under the experimental conditions employed in this research the strong repulsive interactions between the negatively charged latex particles and the clean quartz sands led to minimal colloid immobilization due to physicochemical filtration. The immobilization of the 2.94 μm, 5.1 μm and 6.06 μm latex particles was thus attributed to colloid straining. Experimental results showed that the straining of colloidal particles within heterogeneous sand mixtures increased when the fraction of finer sands increased. The mathematical model that was developed and tested based on results obtained using uniform sands (Xu et al., 2006) was found to be able to describe colloid straining within heterogeneous porous media. Examination of the relationship between the best-fit values of the clean-bed straining rate coefficients (k(0)) and the ratio of colloid diameter (d(p)) and sand grain size (d(g)) indicated that when number-average sizes were used to represent the size of the heterogeneous porous media, there existed a consistent relationship for both uniform sands and heterogeneous sand mixtures. Similarly, the use of the number-averaged sizes for the heterogeneous porous media produced a uniform relationship between the colloid straining capacity term (λ) and the ratio of d(p)/d(g) for all the sand treatments. © 2010 Elsevier Ltd. All rights reserved.

  20. Dynamics of colloidal particles in ice

    KAUST Repository

    Spannuth, Melissa

    2011-01-01

    We use x-ray photon correlation spectroscopy (XPCS) to probe the dynamics of colloidal particles in polycrystalline ice. During freezing, the dendritic ice morphology and rejection of particles from the ice created regions of high particle density, where some of the colloids were forced into contact and formed disordered aggregates. The particles in these high density regions underwent ballistic motion, with a characteristic velocity that increased with temperature. This ballistic motion is coupled with both stretched and compressed exponential decays of the intensity autocorrelation function. We suggest that this behavior could result from ice grain boundary migration. © 2011 American Institute of Physics.

  1. Introduction to Applied Colloid and Surface Chemistry

    DEFF Research Database (Denmark)

    Kontogeorgis, Georgios; Kiil, Søren

    Colloid and Surface Chemistry is a subject of immense importance and implications both to our everyday life and numerous industrial sectors, ranging from coatings and materials to medicine and biotechnology. How do detergents really clean? (Why can’t we just use water ?) Why is milk “milky” Why do......, to the benefit of both the environment and our pocket. Cosmetics is also big business! Creams, lotions and other personal care products are really just complex emulsions. All of the above can be explained by the principles and methods of colloid and surface chemistry. A course on this topic is truly valuable...

  2. Self-assembly of colloidal surfactants

    Science.gov (United States)

    Kegel, Willem

    2012-02-01

    We developed colloidal dumbbells with a rough and a smooth part, based on a method reported in Ref. [1]. Specific attraction between the smooth parts occurs upon addition of non-adsorbing polymers of appropriate size. We present the first results in terms of the assemblies that emerge in these systems. [4pt] [1] D.J. Kraft, W.S. Vlug, C.M. van Kats, A. van Blaaderen, A. Imhof and W.K. Kegel, Self-assembly of colloids with liquid protrusions, J. Am. Chem. Soc. 131, 1182, (2009)

  3. Suspended particles, colloids and radionuclide transport

    International Nuclear Information System (INIS)

    Chapman, N.; McKinley, I.; Shea, M.; Smellie, J.

    1993-01-01

    Radionuclide can be transported either in true solution or associated with suspended particles and colloids. The definitions of colloids and suspended particles are introduced and the mechanisms by which they can influence radionuclide transport discussed. The aim of the Pocos de Caldas investigations was to characterise the natural particulate material in the groundwater, to investigate the association of trace elements with this material and to obtain information on the stability and mobility of the particles. The concentration of suspended particles measured in the groundwater samples were low; the particles also appear to be immobile. (author) 4 figs

  4. Measuring the osmotic pressure of active colloids

    Science.gov (United States)

    Wang, Michael; Soni, Vishal; Magkiriadou, Sofia; Ferrari, Melissa; Youssef, Mina; Driscoll, Michelle; Sacanna, Stefano; Chaikin, Paul; Irvine, William

    We study the behavior of a system of colloidal spinners, consisting of weakly magnetic colloids driven by a rotating magnetic field. First the particles are allowed to sediment to an equilibrium density profile in a gravitational field, from which we measure the equilibrium equation of state. By spinning the particles at various frequencies, we introduce activity into the system through the hydrodynamic interactions between particles. We observe that the activity expands the sedimentation profile to a new steady state, from which we measure the pressure as a function of the density and activity. We compare the effects of activity on the pressure and mean-squared displacement of spinners and tracer particles.

  5. Comparison of intravenous colloid and colloid‑crystalloid ...

    African Journals Online (AJOL)

    2013-09-25

    Sep 25, 2013 ... one crystalloid to colloid ratio in such comparisons. Conflicting results emanate from such studies. Aim: This study was designed to compare the efficacy of equipotent volumes of colloid and crystalloid‑colloid combination in spinal anesthesia‑induced hypotension prophylaxis during cesarean section.

  6. Interplay between Colloids and Interfaces : Emulsions, Foams and Microtubes

    NARCIS (Netherlands)

    de Folter, J.W.J.

    2013-01-01

    The central theme of this thesis is the interplay between colloids and interfaces. The adsorption of colloids at fluid-fluid interfaces is the main topic and covers Chapters 2-6. Pickering emulsions where colloidal particles act as emulsion stabilizers in the absence of surfactants are studied in a

  7. Colloid mobilization and transport during capillary fringe fluctuations.

    Science.gov (United States)

    Aramrak, Surachet; Flury, Markus; Harsh, James B; Zollars, Richard L

    2014-07-01

    Capillary fringe fluctuations due to changing water tables lead to displacement of air-water interfaces in soils and sediments. These moving air-water interfaces can mobilize colloids. We visualized colloids interacting with moving air-water interfaces during capillary fringe fluctuations by confocal microscopy. We simulated capillary fringe fluctuations in a glass-bead-filled column. We studied four specific conditions: (1) colloids suspended in the aqueous phase, (2) colloids attached to the glass beads in an initially wet porous medium, (3) colloids attached to the glass beads in an initially dry porous medium, and (4) colloids suspended in the aqueous phase with the presence of a static air bubble. Confocal images confirmed that the capillary fringe fluctuations affect colloid transport behavior. Hydrophilic negatively charged colloids initially suspended in the aqueous phase were deposited at the solid-water interface after a drainage passage, but then were removed by subsequent capillary fringe fluctuations. The colloids that were initially attached to the wet or dry glass bead surface were detached by moving air-water interfaces in the capillary fringe. Hydrophilic negatively charged colloids did not attach to static air-bubbles, but hydrophobic negatively charged and hydrophilic positively charged colloids did. Our results demonstrate that capillary fringe fluctuations are an effective means for colloid mobilization.

  8. False-positive 111In-pentetreotide Uptake in Gastritis

    International Nuclear Information System (INIS)

    Usmani, Sharjeel; Alshammari, Alshaima

    2013-01-01

    111 In-pentetreotide [ 111 In-octreoscan] is the most widely used radiolabeled somatostatin analog for evaluating neuroendocrine tumor overexpression of somatostatin receptors. False-positives studies of somatostatin receptor scintigraphy have been reported and often the cause is unexplained but assumed to be due to high number of somatostatin receptors in other pathologies. Causes of false-positives include visualization of the gallbladder, nasal mucosa and pulmonary hilar areas in respiratory infections, thyroid abnormalities, accessory spleens, recent Cerebrovascular accidents (CVA's) and activity at the site of a recent surgical incision. In infection or inflammation the cause of false-positive uptake is probably the result of tracer binding by somatostatin receptors on the inflammatory leukocytes. In this case report, we report, a 44-year-old male patient with false-positive 111 In-pentetreotide uptake due to gastritis

  9. Imaging of liver and spleen candidiasis in patients with acute leukemia

    International Nuclear Information System (INIS)

    Seino, Yasuo; Tamakawa, Y.; Kato, T.; Kimura, Y.; Miyazaki, S.; Miura, R.; Ishida, H.

    1988-01-01

    Four patients with acute leukemia were found to have candidal abscess of liver and spleen. CT and US showed hepatosplenomegaly and microabscess. These findings might be useful in diagnosis of visceral candidiasis. (author)

  10. Imaging of liver and spleen candidiasis in patients with acute leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Seino, Yasuo; Tamakawa, Y.; Kato, T.; Kimura, Y.; Miyazaki, S.; Miura, R.; Ishida, H.

    1988-01-01

    Four patients with acute leukemia were found to have candidal abscess of liver and spleen. CT and US showed hepatosplenomegaly and microabscess. These findings might be useful in diagnosis of visceral candidiasis.

  11. Single-incision laparoscopic splenectomy and splenic autotransplantation for an enlarged wandering spleen with torsion.

    Science.gov (United States)

    Katsura, Shunsaku; Kawamura, Daichi; Harada, Eijiro; Enoki, Tadahiko; Hamano, Kimikazu

    2014-06-01

    A wandering spleen is a rare condition in which the spleen is not located in the left upper quadrant, but instead is found in the lower abdomen or in the pelvic region because of the laxity of the peritoneal attachments. The unusually long pedicle is susceptible to twisting, which can lead to ischemia, and eventually to necrosis. We herein report a case of an enlarged wandering spleen with torsion, successfully treated by single-incision laparoscopic splenectomy and autotransplantation. The transplanted splenic tissues could be identified on a spleen scintigram obtained 3 months after the surgery. Howell-Jolly bodies were not observed in blood specimens. This procedure is able to prevent an overwhelming postsplenectomy infection, and leads to satisfactory cosmetic results.

  12. Enhancement of erythroid colony formation in vitro by spleen extract from irradiated rats

    International Nuclear Information System (INIS)

    Kasai, Shiro; Terasawa, Waka; Kodama, Hiroaki; Terasawa, Takashi

    1980-01-01

    The effect of spleen extract from irradiated rats on CFU-e and BFU-e colony formation of rat bone marrow cells was investigated by using modified plasma clot culture media. In the presence of erythropoietin (Ep), CFU-e colony formation peaked at 48 hr of culture, and the Ep-induced increase of CFU-e colonies was dose-dependent. The addition of spleen extract enhanced the colony formation more than two-fold in the Ep-containing culture. BFU-e colony formation was also enhanced by the addition of spleen extract. These results indicate that spleen extract from irradiated rats contains factor(s) which stimulates the proliferation of erythroid progenitors. (author)

  13. Scintigraphic diagnosis and computed tomographic localization of an accessory spleen following relapse of chronic immune thrombocytopaenia

    International Nuclear Information System (INIS)

    Cardaci, G.T.; Blake, M.P.

    1992-01-01

    Chronic immune thrombocytopaenia is an immunologically mediated disorder resulting in disordered platelet kinetics and potentially life-threatening disease. Failure of medical therapy is an indication for splenectomy, and responses are seen in 80% of patients following this procedure. An important cause of relapse following splenectomy is the presence of an accessory spleen. A patient with Hodgkin's Disease developed chronic immune thrombocytopaenia despite previous splenectomy. A remission was induced with immunosuppressive therapy, but he later relapsed. An accessory spleen was detected using 99 m Tc denatured red blood cells and localized using computed tomography. Resection of the accessory spleen resulted in clinical remission. As accessory spleens are often small in size, combined modality imaging is recommended in the evaluation of this disorder. 15 refs., 2 figs

  14. Patient-specific dosimetry for intracavitary 32P-chromic phosphate colloid therapy of cystic brain tumours.

    Science.gov (United States)

    Denis-Bacelar, Ana M; Romanchikova, Marina; Chittenden, Sarah; Saran, Frank H; Mandeville, Henry; Du, Yong; Flux, Glenn D

    2013-10-01

    (32)P-chromic phosphate colloid treatments of astrocytoma and craniopharyngioma cystic brain tumours in paediatric patients are conventionally based on a sphere model under the assumption of uniform uptake. The aims of this study were to determine the distribution of the absorbed dose delivered by (32)P on a patient-specific basis and to evaluate the accuracy with which this can be predicted from a pretherapy administration of (99m)Tc-Sn colloid. Three patients were treated with (32)P-chromic phosphate colloid following (99m)Tc-Sn colloid administrations. Convolution dosimetry was performed using pretherapy and posttherapy sequential SPECT imaging, and verified with EGSnrc Monte Carlo radiation transport simulations. Mean absorbed doses to the cyst wall and dose-volume histograms were also calculated and compared with those obtained by the sphere model approach. Highly nonuniform uptake distributions of both the (99m)Tc and (32)P colloids were observed and characterized by dose-volume histograms to the cyst wall. Mean absorbed doses delivered to the cyst wall, obtained with the convolution method, were on average 21 % (SD 18 %) and 50 % (SD 30 %) lower than those predicted by the (99m)Tc distribution and the uniform assumption of the sphere model, respectively. Absorbed doses delivered to the cyst wall by (32)P are more accurately predicted from image-based patient-specific convolution dosimetry than from simple sphere models. These results indicate the necessity to perform personalized treatment planning and verification for intracavitary irradiation of cystic brain tumours treated with radiocolloids. Patient-specific dosimetry can be used to guide the frequency and levels of repeated administrations and would facilitate data collection and comparison to support the multicentre trials necessary to progress this therapy.

  15. Loss of Sympathetic Nerves in Spleens from Patients with End Stage Sepsis

    Directory of Open Access Journals (Sweden)

    Donald B. Hoover

    2017-12-01

    Full Text Available The spleen is an important site for central regulation of immune function by noradrenergic sympathetic nerves, but little is known about this major region of neuroimmune communication in humans. Experimental studies using animal models have established that sympathetic innervation of the spleen is essential for cholinergic anti-inflammatory responses evoked by vagal nerve stimulation, and clinical studies are evaluating this approach for treating inflammatory diseases. Most data on sympathetic nerves in spleen derive from rodent studies, and this work has established that remodeling of sympathetic innervation can occur during inflammation. However, little is known about the effects of sepsis on spleen innervation. Our primary goals were to (i localize noradrenergic nerves in human spleen by immunohistochemistry for tyrosine hydroxylase (TH, a specific noradrenergic marker, (ii determine if nerves occur in close apposition to leukocytes, and (iii determine if splenic sympathetic innervation is altered in patients who died from end stage sepsis. Staining for vesicular acetylcholine transporter (VAChT was done to screen for cholinergic nerves. Archived paraffin tissue blocks were used. Control samples were obtained from trauma patients or patients who died after hemorrhagic stroke. TH + nerves were associated with arteries and arterioles in all control spleens, occurring in bundles or as nerve fibers. Individual TH + nerve fibers entered the perivascular region where some appeared in close apposition to leukocytes. In marked contrast, spleens from half of the septic patients lacked TH + nerves fibers and the average abundance of TH + nerves for the septic group was only 16% of that for the control group (control: 0.272 ± 0.060% area, n = 6; sepsis: 0.043 ± 0.026% area, n = 8; P < 0.005. All spleens lacked cholinergic innervation. Our results provide definitive evidence for the distribution of noradrenergic

  16. Aniline-induced nitrosative stress in rat spleen: Proteomic identification of nitrated proteins

    International Nuclear Information System (INIS)

    Fan Xiuzhen; Wang Jianling; Soman, Kizhake V.; Ansari, G.A.S.; Khan, M. Firoze

    2011-01-01

    Aniline exposure is associated with toxicity to the spleen which is characterized by splenomegaly, hyperplasia, fibrosis, and a variety of sarcomas on chronic exposure in rats. However, mechanisms by which aniline elicits splenotoxic responses are not well understood. Earlier we have shown that aniline exposure leads to increased nitration of proteins in the spleen. However, nitrated proteins remain to be characterized. Therefore, in the current study using proteomic approaches, we focused on characterizing the nitrated proteins in the spleen of aniline-exposed rats. Aniline exposure led to increased tyrosine nitration of proteins, as determined by 2D Western blotting with anti-3-nitrotyrosine specific antibody, compared to the controls. The analyzed nitrated proteins were found in the molecular weight range of 27.7 to 123.6 kDa. A total of 37 nitrated proteins were identified in aniline-treated and control spleens. Among them, 25 were found only in aniline-treated rats, 11 were present in both aniline-treated and control rats, while one was found in controls only. The nitrated proteins identified mainly represent skeletal proteins, chaperones, ferric iron transporter, enzymes, nucleic acids binding protein, and signaling and protein synthesis pathways. Furthermore, aniline exposure led to significantly increased iNOS mRNA and protein expression in the spleen, suggesting its role in increased reactive nitrogen species formation and contribution to increased nitrated proteins. The identified nitrated proteins provide a global map to further investigate alterations in their structural and functional properties, which will lead to a better understanding of the role of protein nitration in aniline-mediated splenic toxicity. - Highlights: → Proteomic approaches are used to identify nitrated proteins in the spleen. → Twenty five nitrated proteins were found only in the spleen of aniline-treated rats. → Aniline exposure led to increased iNOS mRNA and protein

  17. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... When radiotracer is taken by mouth, in either liquid or capsule form, it is typically swallowed up ... radioactive iodine (I-123 or I-131) in liquid or capsule form to swallow. The thyroid uptake ...

  18. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... is taken by mouth, in either liquid or capsule form, it is typically swallowed up to 24 ... I-123 or I-131) in liquid or capsule form to swallow. The thyroid uptake will begin ...

  19. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... which are encased in metal and plastic and most often shaped like a box, attached to a ... will I experience during and after the procedure? Most thyroid scan and thyroid uptake procedures are painless. ...

  20. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... eat for several hours before your exam because eating can affect the accuracy of the uptake measurement. ... of any allergies you may have or other problems that may have occurred during a previous nuclear ...

  1. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... eat for several hours before your exam because eating can affect the accuracy of the uptake measurement. ... often unattainable using other imaging procedures. For many diseases, nuclear medicine scans yield the most useful information ...

  2. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... of page What will I experience during and after the procedure? Most thyroid scan and thyroid uptake ... you otherwise, you may resume your normal activities after your nuclear medicine scan. If any special instructions ...

  3. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Because nuclear medicine procedures are able to pinpoint molecular activity within the body, they offer the potential ... or imaging device that produces pictures and provides molecular information. The thyroid scan and thyroid uptake provide ...

  4. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... scan and thyroid uptake provide information about the structure and function of the thyroid. The thyroid is ... computer, create pictures offering details on both the structure and function of organs and tissues in your ...

  5. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... scan and uptake uses small amounts of radioactive materials called radiotracers, a special camera and a computer ... last two months that used iodine-based contrast material. Your doctor will instruct you on how to ...

  6. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... eat for several hours before your exam because eating can affect the accuracy of the uptake measurement. ... its radioactivity over time. It may also pass out of your body through your urine or stool ...

  7. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is ... thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that uses ...

  8. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... procedures within the last two months that used iodine-based contrast material. Your doctor will instruct you ... a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is also known as a ...

  9. Sampling and analysis of groundwater colloids. A literature review

    International Nuclear Information System (INIS)

    Takala, M.; Manninen, P.

    2006-03-01

    The purpose of this literature study was to give basic information of colloids: their formation, colloid material, sampling and characterisation of groundwater colloids. Colloids are commonly refereed to as particles in the size range of 1 nm to 1000 nm. They are defined as a suspension of solid material in a liquid that does not appear to separate even after a long period of time. Colloids can be formed from a variety of inorganic or organic material. Inorganic colloids in natural groundwaters are formed by physical fragmentation of the host rock or by precipitation. The water chemistry strongly controls the stability of colloids. The amount of colloid particles in a solution tends to decrease with the increasing ionic strength of the solution. Increases in pH and organic material tend to increase the stability of colloids. The mobility of colloids in a porous medium is controlled mainly by groundwater movement, sedimentation, diffusion and interception. Factors controlling sampling artefacts are oxygen diffusion: leads to e.g. calcite precipitation, pumping rates and filtering techniques. Efforts to minimise artefact formation should be taken if the scope of the sampling programme is to study the colloid particles. The colloid phase size distribution can be determined by light scattering systems, laser induced break down or by single particle analysis using SEM micrographs. Elemental compositions can be analysed with EDS spectrometry from single colloid particles. Bulk compositions of the colloid phase can be analysed with e.g. ICP-MS analyser. The results of this study can be used as guidelines for groundwater colloid samplings. Recommendations for future work are listed in the conclusions of this report. (orig.)

  10. Pore water colloid properties in argillaceous sedimentary rocks.

    Science.gov (United States)

    Degueldre, Claude; Cloet, Veerle

    2016-11-01

    The focus of this work is to evaluate the colloid nature, concentration and size distribution in the pore water of Opalinus Clay and other sedimentary host rocks identified for a potential radioactive waste repository in Switzerland. Because colloids could not be measured in representative undisturbed porewater of these host rocks, predictive modelling based on data from field and laboratory studies is applied. This approach allowed estimating the nature, concentration and size distributions of the colloids in the pore water of these host rocks. As a result of field campaigns, groundwater colloid concentrations are investigated on the basis of their size distribution quantified experimentally using single particle counting techniques. The colloid properties are estimated considering data gained from analogue hydrogeochemical systems ranging from mylonite features in crystalline fissures to sedimentary formations. The colloid concentrations were analysed as a function of the alkaline and alkaline earth element concentrations. Laboratory batch results on clay colloid generation from compacted pellets in quasi-stagnant water are also reported. Experiments with colloids in batch containers indicate that the size distribution of a colloidal suspension evolves toward a common particle size distribution independently of initial conditions. The final suspension size distribution was found to be a function of the attachment factor of the colloids. Finally, calculations were performed using a novel colloid distribution model based on colloid generation, aggregation and sedimentation rates to predict under in-situ conditions what makes colloid concentrations and size distributions batch- or fracture-size dependent. The data presented so far are compared with the field and laboratory data. The colloid occurrence, stability and mobility have been evaluated for the water of the considered potential host rocks. In the pore water of the considered sedimentary host rocks, the clay

  11. Outcome of children with blunt liver or spleen injuries: Experience from a single institution in Korea.

    Science.gov (United States)

    Kim, Ki Hoon; Kim, Jin Soo; Kim, Woon-Won

    2017-02-01

    The aim of this study is to evaluate the demographics, injury pattern, and treatment outcomes among children hospitalized for the management of blunt liver and spleen injury at a single institution in Korea, and to document trends in treatment strategies of children with blunt torso trauma. Children (injuries, hospitalized at our center between May 2010 and February 2016, were included in the present study. Data were retrospectively analyzed for demographic and injury-related information were obtained. During the study period, 34 patients with blunt liver injury and 21 patients with blunt spleen injury presented at the center. The most common cause of liver and spleen injury was motor vehicle collision, followed by fall. Thirty patients (88.2%) with liver injuries and 18 patients (85.7%) with spleen injuries were managed conservatively. No cases of mortality occurred in patients with spleen injury group; one patient (2.9%) died in patients with liver injury due to uncontrolled bleeding. Our data demonstrated that 85.7% of patients with spleen injuries and 88.2% of patients with liver injuries were managed nonoperatively. Operative management was chosen more selectively, being applied in patients with high grade organ injury scores or abrupt changes in vital status. Our findings will contribute to the available data concerning children with traumatic injuries in Korea. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  12. Role of the spleen in the maturation of B-lymphocytes

    International Nuclear Information System (INIS)

    Strober, S.

    1976-01-01

    Spleen cells from unimmunized Lewis rats were fractionated by 1 x g velocity sedimentation and assayed for their ability to restore the adoptive primary antibody response to horse spleen ferritin in irradiated syngeneic recipients given T cell supplementation. Large, medium and small cell fractions all showed virgin B cell activity. Similar studies with thoractic duct cells show that virgin B cell activity is restricted to the small and medium cells. Large spleen cells produced a 2-ME sensitive adoptive antibody response which persisted for 21 days. All antibody produced by small cells at 21 days was 2-ME resistant. Examination of spleen cells during recovery from sublethal irradiation showed that virgin B cell activity was first detected at 14 days, and is confined to the large cell fraction. Experiments with congenic rats which differ at the immunoglobulin (Ig) light chain allotype showed that small cells from the bone marrow injected intravenously can transform into large Ig-bearing cells in the spleen. The relationship of the subclasses of virgin B cells in the spleen to B cell maturation is discussed

  13. [Clinical and experimental study on treatment of anorexy in children with the activating spleen prescription].

    Science.gov (United States)

    Wang, S C; You, R D

    1991-02-01

    The treatment of 488 cases with anorexy in children showed that the curative effect of the group using Chinese medicines based on the differentiation of symptoms and signs by (1) activating the Spleen, (2) invigorating and activating the spleen was significantly higher than the control using concentrated vitamin B complex (P less than 0.001). The results of the experimental study were as follows: Erbao instant granules (the medicine for activating the Spleen) had the effect of raising the D-xylose excretion rate of urine; increasing the ratio of T-lymph cells in blood; raising the quality of 8 mineral elements in hair and the quality of SIgA in saliva; adjusting the abnormal peristalsis of the experimental rabbits and promoting the ability that duodenums which had been separated from rabbits had to absorb different amino acids and glucose. Jian'er syrup (the medicine for invigorating and activating the Spleen) had the effect of raising the quality of 14 mineral elements in hair; increasing the ratio of T-lymph cells in blood; increasing the index of thymus and spleen in the experimental rats and stimulating them to produce hemolysin. The authors tend to think that the therapeutic principle of activating the Spleen can improve appetite, help the body to absorb and utilize various nutrients which contain many kinds of essential trace elements.

  14. Incorporating parasite systematics in comparative analyses of variation in spleen mass and testes sizes of rodents.

    Science.gov (United States)

    Ponlet, Nicolas; Chaisiri, Kitipong; Claude, Julien; Morand, Serge

    2011-11-01

    Parasite diversity is hypothesized to act on host life-history traits through investment in immunity. In order to incorporate the diversity of the parasite community that an individual host or a host species may face, two indices can be used: Taxonomic Species Richness and Taxonomic Entropy, where the taxonomic information is incorporated with the taxonomic weight. We tested whether these indices correlate with several morphological traits potentially implicated in immune defence and in reproduction, using data on gastrointestinal helminths and their rodent hosts sampled in Southeast Asia. We found no relationship between parasite diversity indices and either spleen mass or testes size at the intraspecific level, i.e. at the level of individuals. At the interspecific level, we found no relationship between the parasite diversity indices and testes size. However, we found that female spleen mass is significantly influenced by the specific species richness of parasites, whereas male spleen mass is influenced by individual mean parasite diversity indices. We concluded that female spleen mass may have evolved in response to gastrointestinal helminth pressure acting at species levels, while in males, the individual spleen mass could be constrained by other factors, such as the blood storage function of the spleen.

  15. Age dependence of spleen- and muscle-corrected hepatic signal enhancement on hepatobiliary phase gadoxetate MRI

    Energy Technology Data Exchange (ETDEWEB)

    Matoori, Simon [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Clinic St. Anna, Clinical Research Group, Lucerne (Switzerland); Froehlich, Johannes M. [Hirslanden Clinic St. Anna, Clinical Research Group, Lucerne (Switzerland); ETH Zurich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zurich (Switzerland); Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Breitenstein, Stefan [Cantonal Hospital Winterthur, Department of Surgery, Clinic for Visceral and Thoracic Surgery, Winterthur (Switzerland); Doert, Aleksis [Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Pozdniakova, Viktoria [Stavanger University Hospital, Department of Radiology, Stavanger (Norway); Koh, Dow-Mu [Royal Marsden Hospital, Department of Radiology, Surrey, England (United Kingdom); Gutzeit, Andreas [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Clinic St. Anna, Clinical Research Group, Lucerne (Switzerland); Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland)

    2016-06-15

    To identify correlations of signal enhancements (SE) and SE normalized to reference tissues of the spleen, kidney, liver, musculus erector spinae (MES) and ductus hepatocholedochus (DHC) on hepatobiliary phase gadoxetate-enhanced MRI with patient age in non-cirrhotic patients. A heterogeneous cohort of 131 patients with different clinical backgrounds underwent a standardized 3.0-T gadoxetate-enhanced liver MRI between November 2008 and June 2013. After exclusion of cirrhotic patients, a cohort of 75 patients with no diagnosed diffuse liver disease was selected. The ratio of signal intensity 20 min post- to pre-contrast administration (SE) in the spleen, kidney, liver, MES and DHC, and the SE of the kidney, liver and DHC normalized to the reference tissues spleen or MES were compared to patient age. Patient age was inversely correlated with the liver SE normalized to the spleen and MES SE (both p < 0.001) and proportionally with the SE of the spleen (p = 0.043), the MES (p = 0.030) and the kidney (p = 0.022). No significant correlations were observed for the DHC (p = 0.347) and liver SE (p = 0.606). The age dependence of hepatic SE normalized to the enhancement in the spleen and MES calls for a cautious interpretation of these quantification methods. (orig.)

  16. Spleen Stiffness Correlates with the Presence of Ascites but Not Esophageal Varices in Chronic Hepatitis C Patients

    Directory of Open Access Journals (Sweden)

    Kazuyo Mori

    2013-01-01

    Full Text Available Although spleen stiffness has recently been identified as potential surrogate marker for portal hypertension, the relationship between spleen stiffness and portal hypertension has not been fully elucidated. We attempted to determine the relationship between the liver or spleen stiffness and the presence of ascites or esophageal varices by acoustic radiation force impulse (ARFI imaging. A total of 33 chronic hepatitis C (CHC patients (median age 68; range 51–84 were enrolled. We evaluated the relationship between the liver or spleen stiffness and indicators of portal hypertension as well as clinical and biochemical parameters. Fourteen healthy volunteers were used for validating the accuracy of AFRI imaging. The liver and spleen stiffness increased significantly with progression of liver disease. A significant positive correlation was observed between the liver and spleen stiffness. However, spleen stiffness, but not liver stiffness, was significantly associated with the presence of ascites (, while there was no significant association between the spleen stiffness and spleen index/presence of esophageal varices in CHC patients. The area under the receiver operating characteristic curve based on the spleen stiffness was 0.80. In conclusion, spleen stiffness significantly correlates with the presence of ascites but not esophageal varices in CHC patients.

  17. Size determinations of plutonium colloids using autocorrelation photon spectroscopy

    International Nuclear Information System (INIS)

    Triay, I.R.; Rundberg, R.S.; Mitchell, A.J.; Ott, M.A.; Hobart, D.E.; Palmer, P.D.; Newton, T.W.; Thompson, J.L.

    1989-01-01

    Autocorrelation Photon Spectroscopy (APS) is a light-scattering technique utilized to determine the size distribution of colloidal suspensions. The capabilities of the APS methodology have been assessed by analyzing colloids of known sizes. Plutonium(IV) colloid samples were prepared by a variety of methods including: dilution; peptization; and alpha-induced auto-oxidation of Pu(III). The size of theses Pu colloids was analyzed using APS. The sizes determined for the Pu colloids studied varied from 1 to 370 nanometers. 7 refs., 5 figs., 3 tabs

  18. Pore water colloid properties in argillaceous sedimentary rocks

    Energy Technology Data Exchange (ETDEWEB)

    Degueldre, Claude, E-mail: c.degueldre@lancaster.ac.uk [Engineering Department, University of Lancaster, LA1 4YW Lancaster (United Kingdom); ChiAM & Institute of Environment, University of Geneva, 1211 Genève 4, Swizerland (Switzerland); Earlier, NES, Paul Scherrer Institute, 5232 Villigen (Switzerland); Cloet, Veerle [NAGRA, Hardstrasse 73, 5430 Wettingen (Switzerland)

    2016-11-01

    The focus of this work is to evaluate the colloid nature, concentration and size distribution in the pore water of Opalinus Clay and other sedimentary host rocks identified for a potential radioactive waste repository in Switzerland. Because colloids could not be measured in representative undisturbed porewater of these host rocks, predictive modelling based on data from field and laboratory studies is applied. This approach allowed estimating the nature, concentration and size distributions of the colloids in the pore water of these host rocks. As a result of field campaigns, groundwater colloid concentrations are investigated on the basis of their size distribution quantified experimentally using single particle counting techniques. The colloid properties are estimated considering data gained from analogue hydrogeochemical systems ranging from mylonite features in crystalline fissures to sedimentary formations. The colloid concentrations were analysed as a function of the alkaline and alkaline earth element concentrations. Laboratory batch results on clay colloid generation from compacted pellets in quasi-stagnant water are also reported. Experiments with colloids in batch containers indicate that the size distribution of a colloidal suspension evolves toward a common particle size distribution independently of initial conditions. The final suspension size distribution was found to be a function of the attachment factor of the colloids. Finally, calculations were performed using a novel colloid distribution model based on colloid generation, aggregation and sedimentation rates to predict under in-situ conditions what makes colloid concentrations and size distributions batch- or fracture-size dependent. The data presented so far are compared with the field and laboratory data. The colloid occurrence, stability and mobility have been evaluated for the water of the considered potential host rocks. In the pore water of the considered sedimentary host rocks, the clay

  19. Synthesis and Characterization of Colloidal MCM-41

    Czech Academy of Sciences Publication Activity Database

    Rathouský, Jiří; Zukalová, Markéta; Kooyman, P. J.; Zukal, Arnošt

    2004-01-01

    Roč. 241, - (2004), s. 81-86 ISSN 0927-7757 Institutional research plan: CEZ:AV0Z4040901 Keywords : colloidal MCM-41 * homogeneous precipitation * salt effect in the synthesis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.513, year: 2004

  20. Purification of rhamnolipid using colloidal magnetic nanoparticles ...

    African Journals Online (AJOL)

    Phospholipid-coated colloidal magnetic nanoparticles with mean magnetite core size of 9 nm are shown to be effective ion exchange media for the recovery and purification of Rhaminolipid from culture mixtures. These particles have high adsorption capacity for purification (an order of magnitude larger than the best ...

  1. Rheology and dynamics of colloidal superballs.

    Science.gov (United States)

    Royer, John R; Burton, George L; Blair, Daniel L; Hudson, Steven D

    2015-07-28

    Recent advances in colloidal synthesis make it possible to generate a wide array of precisely controlled, non-spherical particles. This provides a unique opportunity to probe the role that particle shape plays in the dynamics of colloidal suspensions, particularly at higher volume fractions, where particle interactions are important. We examine the role of particle shape by characterizing both the bulk rheology and micro-scale diffusion in a suspension of pseudo-cubic silica superballs. Working with these well-characterized shaped colloids, we can disentangle shape effects in the hydrodynamics of isolated particles from shape-mediated particle interactions. We find that the hydrodynamic properties of isolated superballs are marginally different from comparably sized hard spheres. However, shape-mediated interactions modify the suspension microstructure, leading to significant differences in the self-diffusion of the superballs. While this excluded volume interaction can be captured with a rescaling of the superball volume fraction, we observe qualitative differences in the shear thickening behavior of moderately concentrated superball suspensions that defy simple rescaling onto hard sphere results. This study helps to define the unknowns associated with the effects of shape on the rheology and dynamics of colloidal solutions.

  2. Patchy particles made by colloidal fusion

    Science.gov (United States)

    Gong, Zhe; Hueckel, Theodore; Yi, Gi-Ra; Sacanna, Stefano

    2017-10-01

    Patches on the surfaces of colloidal particles provide directional information that enables the self-assembly of the particles into higher-order structures. Although computational tools can make quantitative predictions and can generate design rules that link the patch motif of a particle to its internal microstructure and to the emergent properties of the self-assembled materials, the experimental realization of model systems of particles with surface patches (or `patchy' particles) remains a challenge. Synthetic patchy colloidal particles are often poor geometric approximations of the digital building blocks used in simulations and can only rarely be manufactured in sufficiently high yields to be routinely used as experimental model systems. Here we introduce a method, which we refer to as colloidal fusion, for fabricating functional patchy particles in a tunable and scalable manner. Using coordination dynamics and wetting forces, we engineer hybrid liquid-solid clusters that evolve into particles with a range of patchy surface morphologies on addition of a plasticizer. We are able to predict and control the evolutionary pathway by considering surface-energy minimization, leading to two main branches of product: first, spherical particles with liquid surface patches, capable of forming curable bonds with neighbouring particles to assemble robust supracolloidal structures; and second, particles with a faceted liquid compartment, which can be cured and purified to yield colloidal polyhedra. These findings outline a scalable strategy for the synthesis of patchy particles, first by designing their surface patterns by computer simulation, and then by recreating them in the laboratory with high fidelity.

  3. Natural and Synthetic Colloids in Veterinary Medicine.

    Science.gov (United States)

    Brooks, Aimee; Thomovsky, Elizabeth; Johnson, Paula

    2016-06-01

    This review article covers basic physiology underlying the clinical use of natural and artificial colloids as well as provide practice recommendations. It also touches on the recent scrutiny of these products in human medicine and how this may have an effect on their use in veterinary medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Towards conducting inks: polypyrrole-silver colloids

    Czech Academy of Sciences Publication Activity Database

    Omastová, M.; Bober, Patrycja; Morávková, Zuzana; Peřinka, N.; Kaplanová, M.; Syrový, T.; Hromádková, Jiřina; Trchová, Miroslava; Stejskal, Jaroslav

    2014-01-01

    Roč. 122, 10 March (2014), s. 296-302 ISSN 0013-4686 R&D Projects: GA TA ČR TE01020022; GA ČR(CZ) GA13-00270S Institutional support: RVO:61389013 Keywords : conducting inks * polypyrrole * colloids Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 4.504, year: 2014

  5. Cubic colloids : Synthesis, functionalization and applications

    NARCIS (Netherlands)

    Castillo, S.I.R.

    2015-01-01

    This thesis is a study on cubic colloids: micron-sized cubic particles with rounded corners (cubic superballs). Owing to their shape, particle packing for cubes is more efficient than for spheres and results in fascinating phase and packing behavior. For our cubes, the particle volume fraction when

  6. Synthesis and properties of colloidal heteronanocrystals

    NARCIS (Netherlands)

    de Mello Donegá, C.

    2011-01-01

    Colloidal heteronanocrystals (HNCs) can be regarded as solution-grown inorganic–organic hybrid nanomaterials, since they consist of inorganic nanoparticles that are coated with a layer of organic ligand molecules. The hybrid nature of these nanostructures provides great flexibility in engineering

  7. The Challenge of Colloidal Nanoparticle Synthesis

    NARCIS (Netherlands)

    Groeneveld, Esther; de Mello-Donega, Celso

    2014-01-01

    Inorganic nanoparticles have developed into one of the main pillars of Nanoscience. Colloidal nanoparticles are particularly attractive as they consist of inorganic particles that are coated with a layer of organic ligand molecules. The hybrid nature of these nanostructures greatly expands the

  8. Chemical modification of colloidal masks for nanolithography

    NARCIS (Netherlands)

    Vossen, D.L.J.; Penninkhof, J.J.; van Blaaderen, A.

    2008-01-01

    A method is presented to tune the holes in colloidal masks used for nanolithography. Using a simple wet-chemical method, a thin layer of silica is grown on masks of silica particles. The size of the holes is controlled by the amount of tetraethoxysilane (TEOS) added. More accurate tuning of the hole

  9. Designing Zirconium Coated Polystyrene Colloids and Application

    Directory of Open Access Journals (Sweden)

    Diana Chira

    2009-01-01

    Full Text Available A simple technique has been developed to prepare core colloids that are modified using zirconium oxychloride, based on heating a solution of core colloid composites, consisting of poly (ethylenimine (PEI and zirconium oxychloride. The interaction of zirconium oxychloride with the polystyrene (PS core colloids has been investigated using Fourier transform-infrared spectroscopy (FT-IR, energy dispersive X-ray spectroscopy (EDX, and scanning electron microscopy (SEM data. FT-IR studies confirm the occurrence of amine groups present in PEI which are oxidized to carboxyl groups after the reaction. The EDX data and the SEM images confirm the presence of zirconium particles immobilized on the polystyrene surfaces. Demeton, a highly toxic nerve agent, was used due to its ability to easily bind through its organophosphate group illustrating a practical application of the PS-PEI-Zr particles. Attenuated Total Reflection (ATR Spectroscopy was used to assess the interactions between the toxic nerve agent demeton-S and the PS-PEI-Zr particles. The results show that the presented technique for coating polystyrene core colloids with zirconium was successfully accomplished, and the newly formed particles easily bond with demeton agents through the P=O functional group.

  10. Dipolar structures in colloidal magnetite dispersions

    NARCIS (Netherlands)

    Klokkenburg, Mark

    2007-01-01

    Dipolar structures in liquid colloidal dispersions comprising well-defined magnetite (Fe3O4) nanoparticles with a permanent magnetic dipole moment are analyzed on a single-particle level by in situ cryogenic transmission electron microscopy (2D). Compared to conventional ferrofluids, these

  11. The colloidal chemistry of ceramic clays

    Science.gov (United States)

    Phelps, G. W.

    1984-01-01

    The colloidal chemistry and mineralogy of two argil minerals were studied. Deposits of kaolin and of ceramic clays in the United States and England are discussed for the probable mechanism of formation. The structural modifications of the bed, original material associated with the clays and the proper use of flocculants are discussed.

  12. Switching Colloidal Superstructures by Critical Casimir Forces.

    Science.gov (United States)

    Nguyen, Truc A; Newton, Arthur; Veen, Sandra J; Kraft, Daniela J; Bolhuis, Peter G; Schall, Peter

    2017-09-01

    Recent breakthroughs in colloidal synthesis promise the bottom-up assembly of superstructures on nano- and micrometer length scales, offering molecular analogues on the colloidal scale. However, a structural control similar to that in supramolecular chemistry remains very challenging. Here, colloidal superstructures are built and controlled using critical Casimir forces on patchy colloidal particles. These solvent-mediated forces offer direct analogues of molecular bonds, allowing patch-to-patch binding with exquisite temperature control of bond strength and stiffness. Particles with two patches are shown to form linear chains undergoing morphological changes with temperature, resembling a polymer collapse under poor-solvent conditions. This reversible temperature switching carries over to particles with higher valency, exhibiting a variety of patch-to-patch bonded structures. Using Monte Carlo simulations, it is shown that the collapse results from the growing interaction range favoring close-packed configurations. These results offer new opportunities for the active control of complex structures at the nano and micrometer scale, paving the way to novel temperature-switchable materials. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Colloidal models. A bit of history

    NARCIS (Netherlands)

    Lyklema, J.

    2015-01-01

    This paper offers an anthology on developments in colloid and interface science emphasizing themes that may be of direct or indirect interest to Interfaces Against Pollution. Topics include the determination of Avogadro’s number, development in the insight into driving forces for double layer

  14. Dynamics of Colloids Confined in Microcylinders

    NARCIS (Netherlands)

    Ghosh, Somnath; Wijnperle, Daniël; Mugele, Friedrich Gunther; Duits, Michael H.G.

    2016-01-01

    We studied both global and local effects of cylindrical confinement on the diffusive behavior of hard sphere (HS) colloids. Using confocal scanning laser microscopy (CSLM) and particle tracking, we measured the mean squared displacement (MSD) of 1 micron sized silica particles in water–glycerol.

  15. Active colloidal propulsion over a crystalline surface

    Science.gov (United States)

    Choudhury, Udit; Straube, Arthur V.; Fischer, Peer; Gibbs, John G.; Höfling, Felix

    2017-12-01

    We study both experimentally and theoretically the dynamics of chemically self-propelled Janus colloids moving atop a two-dimensional crystalline surface. The surface is a hexagonally close-packed monolayer of colloidal particles of the same size as the mobile one. The dynamics of the self-propelled colloid reflects the competition between hindered diffusion due to the periodic surface and enhanced diffusion due to active motion. Which contribution dominates depends on the propulsion strength, which can be systematically tuned by changing the concentration of a chemical fuel. The mean-square displacements (MSDs) obtained from the experiment exhibit enhanced diffusion at long lag times. Our experimental data are consistent with a Langevin model for the effectively two-dimensional translational motion of an active Brownian particle in a periodic potential, combining the confining effects of gravity and the crystalline surface with the free rotational diffusion of the colloid. Approximate analytical predictions are made for the MSD describing the crossover from free Brownian motion at short times to active diffusion at long times. The results are in semi-quantitative agreement with numerical results of a refined Langevin model that treats translational and rotational degrees of freedom on the same footing.

  16. Crystal nucleation of colloidal hard dumbbells

    NARCIS (Netherlands)

    Ni, R.; Dijkstra, M.

    2011-01-01

    Using computer simulations, we investigate the homogeneous crystal nucleation in suspensions of colloidal hard dumbbells. The free energy barriers are determined by Monte Carlo simulations using the umbrella sampling technique. We calculate the nucleation rates for the plastic crystal and the

  17. Self-assembly of patchy colloidal dumbbells

    NARCIS (Netherlands)

    Avvisati, Guido; Vissers, Teun; Dijkstra, Marjolein

    2015-01-01

    We employ Monte Carlo simulations to investigate the self-assembly of patchy colloidal dumbbells interacting via a modified Kern-Frenkel potential by probing the system concentration and dumbbell shape. We consider dumbbells consisting of one attractive sphere with diameter sigma(1) and one

  18. Colloidal photonic crystals: from lasing to microfluidics

    Science.gov (United States)

    Clays, Koen; Zhong, Kuo; Song, Kai

    2017-08-01

    Colloidal photonic crystals are photonic crystals made by bottom-up physical chemistry strategies from monodisperse colloidal particles. The self-assembly process is automatically leading to inherently three-dimensional structures with their optical properties determined by the periodicity, induced by this ordering process, in the dielectric properties of the colloidal material. The best-known optical effect is the photonic band gap, the range of energies, or wavelengths, that is forbidden for photons to exist in the structure. This photonic band gap is similar to the electronic band gap of electronic semiconductor crystals. We have previously shown how with the proper photonic band gap engineering, we can insert allowed pass band defect modes and use the suppressing band gap in combination with the transmitting pass band to induce spectral narrowing of emission. We show now how with a high-quality narrow pass band in a broad stop band, it is possible to achieve photonic crystal lasing in self-assembled colloidal photonic crystals with a planar defect. In addition, with proper surface treatment in combination with patterning, we prepare for addressable integrated photonics. Finally, by incorporating a water in- and outlet, we can create optomicrofluidic structures on a photonic crystal allowing the optical probing of microreactors or micro-stopped-flow in the lab-on-an-optical-chip.

  19. Prospects of Colloidal Copper Chalcogenide Nanocrystals

    NARCIS (Netherlands)

    van der Stam, W.; Berends, A.C.; de Mello-Donega, Celso

    2016-01-01

    Over the past few years, colloidal copper chalcogenide nanocrystals (NCs) have emerged as promising alternatives to conventional Cd and Pb chalcogenide NCs. Owing to their wide size, shape, and composition tunability, Cu chalcogenide NCs hold great promise for several applications, such as

  20. Growth and Interaction of Colloid Nuclei

    Science.gov (United States)

    Lam, Michael-Angelo; Khusid, Boris; Meyer, William; Kondic, Lou

    2017-11-01

    We study evolution of colloid systems under zero-gravity conditions. In particular, we focus on the regime where there is a coexistence between a liquid and a solid state. Under zero gravity, the dominating process in the bulk of the fluid phase and the solid phase is diffusion. At the moving solid/liquid interface, osmotic pressure is balanced by surface tension, as well as balancing fluxes (conservation of mass) with the kinematics of nuclei growth (Wilson-Frenkel law). Due to the highly nonlinear boundary condition at the moving boundary, care has to be taken when performing numerical simulations. In this work, we present a nonlinear model for colloid nuclei growth. Numerical simulations using a finite volume method are compared with asymptotic analysis of the governing equation and experimental results for nuclei growth. Novel component in our numerical simulations is the inclusion of nonlinear (collective) diffusion terms that depend on the chemical potentials of the colloid in the solid and fluid phase. The results include growth and dissolution of a single colloidal nucleus, as well as evolution of multiple interacting nuclei. Supported by NASA Grant No. NNX16AQ79G.

  1. Random packing of colloids and granular matter

    NARCIS (Netherlands)

    Wouterse, A.

    2008-01-01

    This thesis deals with the random packing of colloids and granular matter. A random packing is a stable disordered collection of touching particles, without long-range positional and orientational order. Experimental random packings of particles with the same shape but made of different materials

  2. Room temperature synthesis of colloidal platinum nanoparticles

    Indian Academy of Sciences (India)

    Unknown

    1988) and application also in optical, electronic and mag- netic devices (Schon and Simon 1995). The catalytic reacti- vity depend on size and shape of nanoparticles and therefore synthesis of controlled shapes and size of colloidal platinum particles could be critical for these applications. Nanostructured materials promise ...

  3. Programming Hierarchical Self-Assembly of Patchy Particles into Colloidal Crystals via Colloidal Molecules.

    Science.gov (United States)

    Morphew, Daniel; Shaw, James; Avins, Christopher; Chakrabarti, Dwaipayan

    2018-03-27

    Colloidal self-assembly is a promising bottom-up route to a wide variety of three-dimensional structures, from clusters to crystals. Programming hierarchical self-assembly of colloidal building blocks, which can give rise to structures ordered at multiple levels to rival biological complexity, poses a multiscale design problem. Here we explore a generic design principle that exploits a hierarchy of interaction strengths and employ this design principle in computer simulations to demonstrate the hierarchical self-assembly of triblock patchy colloidal particles into two distinct colloidal crystals. We obtain cubic diamond and body-centered cubic crystals via distinct clusters of uniform size and shape, namely, tetrahedra and octahedra, respectively. Such a conceptual design framework has the potential to reliably encode hierarchical self-assembly of colloidal particles into a high level of sophistication. Moreover, the design framework underpins a bottom-up route to cubic diamond colloidal crystals, which have remained elusive despite being much sought after for their attractive photonic applications.

  4. Assembly of Colloidal Materials Using Bioadhesive Interactions

    Science.gov (United States)

    Hammer, Daniel A.; Hiddessen, Amy L.; Tohver, Valeria; Crocker, John C.; Weitz, David A.

    2002-01-01

    We have pursued the use of biological crosslinking molecules of several types to make colloidal materials at relatively low volume fraction of colloidal particles. The objective is to make binary alloys of colloidal particles, made of two different colloidal particles coated with complementary biological lock-and-key binding molecules, which assemble due to the biological specificity. The long-term goal is to use low affinity lock-and-key biological interactions, so that the can anneal to form crystalline states. We have used a variety of different surface chemistries in order to make colloidal materials. Our first system involved using selectin-carbohydrate (sialyl-Lewis) interactions; this chemistry is derived from immune system. This chemical interaction is of relatively low affinity, with timescales for dissociation of several seconds. Furthermore, the adhesion mediated by these molecules can be reversed by the chelation of calcium atoms; thus assembled structures can be disassembled reversibly. Our second system employed avidin-biotin chemistry. This well-studied system is of high affinity, and is generally irreversible on a laboratory time-scale. Thus, we would expect selectin-carbohydrate interactions at high molecular density and avidin-biotin interactions to give kinetically-trapped structures; however, at low densities, we would expect significant differences in the structure and dynamics of the two materials, owing to their very different release rates. We have also begun to use a third chemistry - DNA hybridization. By attaching single stranded DNA oligonucleotide chains to beads, we can drive the assembly of colloidal materials by hybridization of complementary DNA chains. It is well known that DNA adenosine-thymine (A-T) and guanine-cytosine (G-C) bases hybridize pairwise with a Gibbs free energy change of 1.7 kcal/mol per base; thus, the energy of the assembly can be modulated by altering the number of complementary bases in the DNA chains. Using

  5. Colloid suspension stability and transport through unsaturated porous media

    Energy Technology Data Exchange (ETDEWEB)

    McGraw, M.A.; Kaplan, D.I.

    1997-04-01

    Contaminant transport is traditionally modeled in a two-phase system: a mobile aqueous phase and an immobile solid phase. Over the last 15 years, there has been an increasing awareness of a third, mobile solid phase. This mobile solid phase, or mobile colloids, are organic or inorganic submicron-sized particles that move with groundwater flow. When colloids are present, the net effect on radionuclide transport is that radionuclides can move faster through the system. It is not known whether mobile colloids exist in the subsurface environment of the Hanford Site. Furthermore, it is not known if mobile colloids would likely exist in a plume emanating from a Low Level Waste (LLW) disposal site. No attempt was made in this study to ascertain whether colloids would form. Instead, experiments and calculations were conducted to evaluate the likelihood that colloids, if formed, would remain in suspension and move through saturated and unsaturated sediments. The objectives of this study were to evaluate three aspects of colloid-facilitated transport of radionuclides as they specifically relate to the LLW Performance Assessment. These objectives were: (1) determine if the chemical conditions likely to exist in the near and far field of the proposed disposal site are prone to induce flocculation (settling of colloids from suspension) or dispersion of naturally occurring Hanford colloids, (2) identify the important mechanisms likely involved in the removal of colloids from a Hanford sediment, and (3) determine if colloids can move through unsaturated porous media.

  6. Dynamic Colloidal Molecules Maneuvered by Light-Controlled Janus Micromotors.

    Science.gov (United States)

    Gao, Yirong; Mou, Fangzhi; Feng, Yizheng; Che, Shengping; Li, Wei; Xu, Leilei; Guan, Jianguo

    2017-07-12

    In this work, we propose and demonstrate a dynamic colloidal molecule that is capable of moving autonomously and performing swift, reversible, and in-place assembly dissociation in a high accuracy by manipulating a TiO 2 /Pt Janus micromotor with light irradiation. Due to the efficient motion of the TiO 2 /Pt Janus motor and the light-switchable electrostatic interactions between the micromotor and colloidal particles, the colloidal particles can be captured and assembled one by one on the fly, subsequently forming into swimming colloidal molecules by mimicking space-filling models of simple molecules with central atoms. The as-demonstrated dynamic colloidal molecules have a configuration accurately controlled and stabilized by regulating the time-dependent intensity of UV light, which controls the stop-and-go motion of the colloidal molecules. The dynamic colloidal molecules are dissociated when the light irradiation is turned off due to the disappearance of light-switchable electrostatic interaction between the motor and the colloidal particles. The strategy for the assembly of dynamic colloidal molecules is applicable to various charged colloidal particles. The simulated optical properties of a dynamic colloidal molecule imply that the results here may provide a novel approach for in-place building functional microdevices, such as microlens arrays, in a swift and reversible manner.

  7. Colloid-Mediated Transport of PPCPs through Porous Media

    Science.gov (United States)

    Chen, Xijuan; Xing, Yingna; Chen, Xin; Zhuang, Jie

    2017-04-01

    Pharmaceutical and personal care products (PPCPs) enter the soil through reclaimed water irrigation and biosolid land application. Colloids, such as clays that are present in soil, may interact with PPCPs to affect their fate and transport in the subsurface environment. This study addresses how soil colloids mediate the sorption and transport behaviors of PPCPs through laboratory column experiments. The affinities of PPCPs for colloids as well as the influence factors were investigated. For PPCPs that have high sorption (e.g., ciprofloxacin with Kd ˜104-5 L/kg) on soil colloids, the transport is dominantly controlled by colloids, with a higher extent of colloid-facilitated effect at lower ionic strength. For PPCPs that have intermediate sorption (e.g., tetracycline with Kd ˜103-4 L/kg) on soil colloids, the mobility of dissolved and colloid-bound PPCPs respond oppositely to the effect of changes in solution ionic strength, making the net effect of soil colloids on PPCP transport variable with soil solution chemistry. For PPCPs with low sorption (e.g., ibuprofen with Kd ˜102-3 L/kg) on soil colloids, other measures (such as pre-filtration) must be taken. This study suggested that colloids are significant carriers of PPCPs in the subsurface environment and could affect their off-site environmental risks.

  8. Colloid Mobilization and Transport during Capillary Fringe Fluctuations

    Science.gov (United States)

    Aramrak, Surachet; Flury, Markus

    2016-04-01

    Capillary fringe fluctuations due to changing water tables lead to displacement of air-water interfaces in soils and sediments. These moving air-water interfaces can mobilize colloids. We visualized colloids interacting with moving air-water interfaces during capillary fringe fluctuations by confocal microscopy. We simulated capillary fringe fluctuations in a glass-bead filled column. Confocal images showed that the capillary fringe fluctuations affect colloid transport behavior. Hydrophilic negatively-charged colloids initially suspended in the aqueous phase were deposited at the solid-water interface after a drainage passage, but then were removed by subsequent capillary fringe fluctuations. The colloids that were initially attached to the wet or dry glass bead surface were detached by moving air-water interfaces in the capillary fringe. Hydrophilic negatively-charged colloids did not attach to static air-bubbles, but hydrophobic negatively-charged and hydrophilic positively-charged colloids did.

  9. Active structuring of colloidal armour on liquid drops

    Science.gov (United States)

    Dommersnes, Paul; Rozynek, Zbigniew; Mikkelsen, Alexander; Castberg, Rene; Kjerstad, Knut; Hersvik, Kjetil; Otto Fossum, Jon

    2013-06-01

    Adsorption and assembly of colloidal particles at the surface of liquid droplets are at the base of particle-stabilized emulsions and templating. Here we report that electrohydrodynamic and electro-rheological effects in leaky-dielectric liquid drops can be used to structure and dynamically control colloidal particle assemblies at drop surfaces, including electric-field-assisted convective assembly of jammed colloidal ‘ribbons’, electro-rheological colloidal chains confined to a two-dimensional surface and spinning colloidal domains on that surface. In addition, we demonstrate the size control of ‘pupil’-like openings in colloidal shells. We anticipate that electric field manipulation of colloids in leaky dielectrics can lead to new routes of colloidosome assembly and design for ‘smart armoured’ droplets.

  10. LONG-TERM COLLOID MOBILIZATION AND COLLOID-FACILITATED TRANSPORT OF RADIONUCLIDES IN A SEMI-ARID VADOSE ZONE

    Energy Technology Data Exchange (ETDEWEB)

    Markus Flury; James B. Harsh; Fred Zhang; Glendon W. Gee; Earl D. Mattson; Peter C. L

    2012-08-01

    The main purpose of this project was to improve the fundamental mechanistic understanding and quantification of long-term colloid mobilization and colloid-facilitated transport of radionuclides in the vadose zone, with special emphasis on the semi-arid Hanford site. While we focused some of the experiments on hydrogeological and geochemical conditions of the Hanford site, many of our results apply to colloid and colloid-facilitated transport in general. Specific objectives were (1) to determine the mechanisms of colloid mobilization and colloid-facilitated radionuclide transport in undisturbed Hanford sediments under unsaturated flow, (2) to quantify in situ colloid mobilization and colloid-facilitated radionuclidetransport from Hanford sediments under field conditions, and (3) to develop a field-scale conceptual and numerical model for colloid mobilization and transport at the Hanford vadose zone, and use that model to predict long-term colloid and colloid- facilitated radionuclide transport. To achieve these goals and objectives, we have used a combination of experimental, theoretical, and numerical methods at different spatial scales, ranging from microscopic investigationsof single particle attachment and detachment to larger-scale field experiments using outdoor lysimeters at the Hanford site. Microscopic and single particle investigations provided fundamental insight into mechanisms of colloid interactions with the air-water interface. We could show that a moving air water interface (such as a moving water front during infiltration and drainage) is very effective in removing and mobilizing particles from a stationary surface. We further demonstrated that it is particularly the advancing air-water interface which is mainly responsible for colloid mobilization. Forces acting on the colloids calculated from theory corroborated our experimental results, and confirm that the detachment forces (surface tension forces) during the advancing air-water interface

  11. Preferences for colloid use in Scandinavian intensive care units.

    Science.gov (United States)

    2008-07-01

    Fluid resuscitation is a frequent intervention in intensive care. Colloids are widely used, but recent data suggest harm by some of these solutions. This calls for more clinical studies on this matter, but the current preferences for colloid use in Scandinavian intensive care units (ICUs) are unknown. In March-May 2007, 120 Scandinavian ICUs were invited to answer a web-based survey consisting of 18 questions on types of colloids, indications, contraindications and rationale of use. Seventy-three ICUs, of which 31 were university hospital units, answered the questionnaire. Most ICUs used both synthetic and natural colloids, and hydroxyethyl starch (HES) 130/0.4 was the preferred colloid in 59 units. Eleven ICUs had protocols for colloid use. The most frequent indication was second-line fluid for hypovolaemia, but one in three ICUs used colloids as first-line fluid. Thirty-five ICUs had contraindications, which were mainly for the use of synthetic colloids (acute renal failure 25 units, bleeding 15 units). Most units based the use of colloids on theoretical knowledge and tradition. Sixty-five and 54 ICUs were ready to change colloid use based on data from randomised trials of ICU patients showing changes in mortality or renal function, respectively. Most Scandinavian ICUs use both synthetic and natural colloids, but HES 130/0.4 is by far the preferred colloid. Few units have protocols for colloid use, but most use them for hypovolaemia, and the majority have no contraindications. Most ICUs are ready to change colloid use if randomised trials in ICU patients show changes in mortality or renal function.

  12. Colloids from the aqueous corrosion of uranium nuclear fuel

    Science.gov (United States)

    Kaminski, M. D.; Dimitrijevic, N. M.; Mertz, C. J.; Goldberg, M. M.

    2005-12-01

    Colloids may enhance the subsurface transport of radionuclides and potentially compromise the long-term safe operation of the proposed radioactive waste repository at Yucca Mountain. Little data is available on colloid formation for the many different waste forms expected to be buried in the repository. This work expands the sparse database on colloids formed during the corrosion of metallic uranium nuclear fuel. We characterized spherical UO 2 and nickel-rich montmorilonite smectite-clay colloids formed during the corrosion of uranium metal fuel under bathtub conditions at 90 °C. Iron and chromium oxides and calcium carbonate colloids were present but were a minor population. The estimated upper concentration of the UO 2 and clays was 4 × 10 11 and 7 × 10 11-3 × 10 12 particles/L, respectively. However, oxygen eventually oxidized the UO 2 colloids, forming long filaments of weeksite K 2(UO 2) 2Si 6O 15 · 4H 2O that settled from solution, reducing the UO 2 colloid population and leaving predominantly clay colloids. The smectite colloids were not affected by oxygen. Plutonium was not directly observed within the UO 2 colloids but partitioned completely to the colloid size fraction. The plutonium concentration in the colloidal fraction was slightly higher than the value used in the viability assessment model, and does not change in concentration with exposure to oxygen. This paper provides conclusive evidence for single-phase radioactive colloids composed of UO 2. However, its impact on repository safety is probably small since oxygen and silica availability will oxidize and effectively precipitate the UO 2 colloids from concentrated solutions.

  13. Transformation of organo-ferric peat colloids by a heterotrophic bacterium

    Science.gov (United States)

    Oleinikova, Olga V.; Shirokova, Liudmila S.; Gérard, Emmanuele; Drozdova, Olga Yu.; Lapitskiy, Sergey A.; Bychkov, Andrey Yu.; Pokrovsky, Oleg S.

    2017-05-01

    Bacterial mineralization of allochthonous (soil) dissolved organic matter (DOM) in boreal waters governs the CO2 flux from the lakes and rivers to the atmosphere, which is one of the main factor of carbon balance in high latitudes. However, the fate of colloidal trace element (TE) during bacterial processing of DOM remains poorly constrained. We separated monoculture of Pseudomonas saponiphila from a boreal creek and allowed it to react with boreal Fe-rich peat leachate of approximate colloidal (3 kDa-0.45 μm) composition C1000Fe12Al3.3Mg2Ca3.7P1.2Mn0.1Ba0.5 in nutrient-free media. The total net decrease of Dissolved Organic Carbon (DOC) concentration over 4 day of exposure was within 5% of the initial value, whereas the low molecular weight fraction of Corg (LMWbio-uptake or coagulation. There was a relative depletion in Fe over Corg of 0.45 μm, colloidal and LMW fraction in the course of peat leachate interaction with P. saponiphila. Al, Mn, Ni, Cu, Ga, REEs, Y, U were mostly affected by bacterial presence and exhibited essentially the adsorption at the cell surface over first hours of reaction, in contrast to Fe, Ti, Zr, and Nb that showed both short-term adsorption and long-term removal by physical coagulation/coprecipitation with Fe hydroxide. The low molecular weight fraction (LMWadsorption or removal than the high molecular weight (HMW) colloidal fractions (<0.45 μm and <50 kDa). The climate change-induced acceleration of heterotrophic bacterial activity in boreal and subarctic waters may lead to preferential removal of Fe over DOC from conventionally dissolved fraction and the decrease of the proportion of LMW < 3 kDa fraction and the increase of HMW colloids. Enhanced heterotrophic mineralization of organo-ferric colloids under climate warming scenario may compensate for on-going "browning" of surface waters.

  14. Autotransplantation of Spleen Mitigates Drug-Induced Liver Damage in Splenectomized Mice.

    Science.gov (United States)

    Grunewald, Sabrine Teixeira Ferraz; Rezende, Alice Belleigoli; Figueiredo, Bárbara Bruna Muniz; Mendonça, Ana Carolina de Paula; Almeida, Caroline de Souza; de Oliveira, Erick Esteves; de Paoli, Flávia; Teixeira, Henrique Couto

    2017-12-01

    The spleen presents numerous functions, including the production of immunoglobulins and blood filtration, removing microorganisms and cellular debris. The spleen also has anatomical and functional relationship with the liver, but there are few studies on this topic. The aim of this study was to assess the effect of splenectomy and autologous spleen transplantation on both filtering functions of spleen and acetaminophen-induced hepatotoxicity. Fifty-two BALB/c mice were randomized into four groups: splenectomized; splenectomy and splenic autotransplantation in the greater omentum; sham operated control; and non-operated control. At day 7th, 14th, and 28th after surgery, splenic filtration was assessed by counting Howell-Jolly bodies (HJB) and pitted red cells (PIT). The animals received 400 mg/kg acetaminophen by gavage at day 28 th and after 12 or 24 hours were euthanized for evaluation of splenic and hepatic morphology. The splenectomized group demonstrated reduced filtration of HJB and PIT in all analyzes, while the autotransplanted group developed progressive recovery of function after the 14th day. At day 28 after surgery the implants showed similar histology in comparison to normal spleen. Liver histology showed more intense centrilobular necrosis in splenectomized group in comparison to the others, suggesting a protective role of spleen in acetaminophen-induced liver injury. Splenic implants showed structural and functional recovery, demonstrating the ability of autologous implant to rescue filtering function of intact spleen. Furthermore, the integrity of splenic function appears to influence liver morphology, since the presence of the splenic implants mitigated the effects of chemically-induced liver damage.

  15. Ginsenoside Rg1 improves bone marrow haematopoietic activity via extramedullary haematopoiesis of the spleen.

    Science.gov (United States)

    Liu, Hua-Hsing; Chen, Fei-Peng; Liu, Rong-Kai; Lin, Chun-Lin; Chang, Ko-Tung

    2015-11-01

    Cyclophosphamide (CY) is a chemotherapeutic agent used for cancer and immunological diseases. It induces cytotoxicity of bone marrow and causes myelosuppression and extramedullary haematopoiesis (EMH) in treated patients. EMH is characterized with the emergence of multipotent haematopoietic progenitors most likely in the spleen and liver. Previous studies indicated that a Chinese medicine, ginsenoside Rg1, confers a significant effect to elevate the number of lineage (Lin(-) ) Sca-1(+) c-Kit(+) haematopoietic stem and progenitor cells (HSPCs) and restore the function of bone marrow in CY-treated myelosuppressed mice. However, whether the amelioration of bone marrow by Rg1 accompanies an alleviation of EMH in the spleen was still unknown. In our study, the cellularity and weight of the spleen were significantly reduced after Rg1 treatment in CY-treated mice. Moreover, the number of c-Kit(+) HSPCs was significantly decreased but not as a result of apoptosis, indicating that Rg1 alleviated EMH of the spleen induced by CY. Unexpectedly, the proliferation activity of c-Kit(+) HSPCs was only up-regulated in the spleen, but not in the bone marrow, after Rg1 treatment in CY-treated mice. We also found that a fraction of c-Kit(+) /CD45(+) HSPCs was simultaneously increased in the circulation after Rg1 treatment. Interestingly, the effects of Rg1 on the elevation of HSPCs in bone marrow and in the peripheral blood were suppressed in CY-treated splenectomized mice. These results demonstrated that Rg1 improves myelosuppression induced by CY through its action on the proliferation of HSPCs in EMH of the spleen and migration of HSPCs from the spleen to the bone marrow. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  16. Studies on the preparation and evaluation of colloidal chromic phosphate - 32P for possible therapeutic use

    International Nuclear Information System (INIS)

    Prabhakar, G.; Mehra, K.S.; Ramamoorthy, N.

    2001-01-01

    Radionuclide therapy has become the focus of recent attention in nuclear medicine, thanks to the emergence of new therapeutic radionuclides as well as the known prospects of local instillation approach and the exciting promise of targeted therapy concept. This has naturally led to a revived interest in the use of established products of earlier generation also, for example 32 P compounds. In response to such a demand of nuclear medicine physicians in India, 32 P labelled colloidal chromic phosphate suspension (CCPS) was prepared by suitable modifications to a reported procedure. 51 Cr was used as tracer for initial studies of standardisation, in order to avail the benefits of relatively greater ease and higher efficiency of assay of gamma activity at low levels. Recovery of the colloid and purification were accomplished by dialysis leading to about 60% radiochemical (RC) yield. The RC purity of the CCPS formulated in 30% dextrose solution was over 98% as assessed by paper chromatography. The particle size was below 5μM, with nearly 99% of the particles present in the size range of 0.6-2.5 μM. The stability of the colloid was found to be not less than 7 days, in terms of soluble phosphate content of the CCPS. The consistency of biological behaviour of CCPS was attempted to be studied by i.v. administration in test animals, although the envisaged end use is only by local instillation. The animal studies revealed prominent lung uptake (∼70%) indicating the presence of >10μM particles formed in vivo, most probably due to agglomeration in serum. The easy reliable preparation of CCPS in acceptable yield, purity and particle size distribution demonstrated in the present study, considered along with the added advantages of abundant, economic availability and convenient production logistics of no-carrier-added 32 P, would merit further investigations on CCPS and similar *M(III)-phosphate colloids for possible therapeutic applications. (author)

  17. [Ginkgo biloba extract enhances the immune function of spleen and thymus in SD rats].

    Science.gov (United States)

    Wang, Yong; Si, Lifang; Li, Xiangneng; Li, Zhansheng

    2015-06-01

    To study the effect of Ginkgo biloba extract (GBE) on the immune function of spleen and thymus in SD rats. Forty SD rats were randomly divided into four groups (10 rats each group). Three experimental groups were given GBE daily by gavage in doses of 40, 120, 360 mg/(kg.d), respectively. Animals in the control group were fed the same amount of PBS. After 28 days, the rats were sacrificed by chloral hydrate anesthesia. The spleen and thymus were harvested to determine the organ index first. MTT assay was used to detect the concanavalin A (ConA)-induced splenic lymphocyte proliferation and transformation. Neutral red assay was performed to measure the rat peritoneal macrophage phagocytosis. The ultrastructural changes of spleen and thymus were observed under scanning electron microscope. Administration of GBE in the rats increased the mass indexes of rat thymus and spleen, dose-dependently elevated the lymphocyte proliferative responses and enhanced the peritoneal macrophage phagocytosis. In experimental groups, the numbers of mature spleen and thymus lymphocytes were significantly raised in comparison with the control rats. GBE plays a regulatory role in immune function of the rat by increasing the mass of immune organs, increasing the number of mature T lymphocytes as well as their proliferative responses, and enhancing the phagocytic capacity of peritoneal macrophages.

  18. Autophagy induces apoptosis and death of T lymphocytes in the spleen of pigs infected with CSFV.

    Science.gov (United States)

    Gou, Hongchao; Zhao, Mingqiu; Fan, Shuangqi; Yuan, Jin; Liao, Jiedan; He, Wencheng; Xu, Hailuan; Chen, Jinding

    2017-10-19

    Lymphocyte depletion and immunosuppression are typical clinical characteristics of pigs infected with classical swine fever virus (CSFV). The apoptosis of virus-infected and bystander cells plays a role in the immunopathology of classical swine fever (CSF). Here, we offer the first evidence that autophagy is involved in apoptosis and death of T lymphocytes in the spleen of pigs infected with CSFV. Using immunohistochemical assays, we observed that more LC3II-positive cells appear in the T-cell zone of spleens. Spleen cell apoptosis was demonstrated using flow cytometry and TUNEL staining. Confocal immunofluorescence revealed that partial LC3II-positive cells were simultaneously TUNEL-positive. By cultivating spleen cells ex vivo, we demonstrated that the inhibition of autophagy by 3-MA treatment inhibited apoptosis and death of T lymphocytes caused by CSFV infection but did not have this effect  on B lymphocytes. Further observations demonstrated that uninfected cells in the spleen were also undergoing autophagy in vivo. In summary, these results linked autophagy with the apoptosis and cell death of splenic T cells, providing a new outlook to understand the mechanism of T lymphocyte depletion and immunosuppression during CSF.

  19. [Acute torsion of wandering spleen: a rare cause of acute abdomen].

    Science.gov (United States)

    de Andrés-Asenjo, Beatriz; Fernández-González, Nuria

    2012-01-01

    Wandering spleen is a rare clinical entity characterized by an anomalous position of the spleen in the abdomen due to impaired splenic ligamentous attachments that produce an elongation of the vascular pedicle. This makes a partial or complete volvulus of the vascular axis more likely. Wandering spleen's clinical presentation is variable--from an asymptomatic patient to one with chronic abdominal pain or an acute abdomen. The most common complication is the acute torsion of the splenic pedicle causing acute abdominal pain. A 30-year-old woman who turned up at the Emergency Department with acute abdominal pain. Diagnostic imaging (ultrasonography and computerized axial tomography) revealed a huge spleen in an abnormal location and without vascularization. An urgent splenectomy was performed. Acute torsion of wandering spleen is a rare cause of acute abdomen, which makes early diagnosis difficult and can result in delayed treatment. This would lead to having to perform a splenectomy. Due to splenic necrosis or infarction, which increases the risk of postsplenectomy sepsis.

  20. Ames hypopituitary dwarf mice demonstrate imbalanced myelopoiesis between bone marrow and spleen.

    Science.gov (United States)

    Capitano, Maegan L; Chitteti, Brahmananda R; Cooper, Scott; Srour, Edward F; Bartke, Andrzej; Broxmeyer, Hal E

    2015-06-01

    Ames hypopituitary dwarf mice are deficient in growth hormone, thyroid-stimulating hormone, and prolactin. The phenotype of these mice demonstrates irregularities in the immune system with skewing of the normal cytokine milieu towards a more anti-inflammatory environment. However, the hematopoietic stem and progenitor cell composition of the bone marrow (BM) and spleen in Ames dwarf mice has not been well characterized. We found that there was a significant decrease in overall cell count when comparing the BM and spleen of 4-5 month old dwarf mice to their littermate controls. Upon adjusting counts to differences in body weight between the dwarf and control mice, the number of granulocyte-macrophage progenitors, confirmed by immunophenotyping and colony-formation assay was increased in the BM. In contrast, the numbers of all myeloid progenitor populations in the spleen were greatly reduced, as confirmed by colony-formation assays. This suggests that there is a shift of myelopoiesis from the spleen to the BM of Ames dwarf mice; however, this shift does not appear to involve erythropoiesis. The reasons for this unusual shift in spleen to marrow hematopoiesis in Ames dwarf mice are yet to be determined but may relate to the decreased hormone levels in these mice. Copyright © 2015. Published by Elsevier Inc.

  1. Spleen and thymic sonography as estimator of the immune response in children with repeated infections

    International Nuclear Information System (INIS)

    Rabaza, Jesus; Fundora, Hermes; Rodriguez, Alexis; Hernandez, Maria de los Angeles

    2010-01-01

    The spleen is a secondary lymphoid organ. The spleen has many functions: IgM class antibody production and phagocytosis of encapsulated bacteria. We propose to measure the dimensions of the spleen in children with repeated infections, in order to describe them as a diagnosis marker and to explore the probable correlation between the thymic characteristics and the dimensions of the spleen. We study 81 patients that attended the consultation of Immunology from Aballi hospital with repeated infections and they were from 8 months to 9 years old. Children with nutritional value up to the third percentile and those taking steroids 45 days before the study were excluded. We measured the thymic and splenic areas by mediastinal and abdominal echography. The length, the splenic index and the weight are less in patients with repeated infections. These data were significant in 12 to 23 month of age group. The length and the splenic index were less in patients with depletion of thymic area. The sonographic evaluation of the spleen is very important in patients from 1 to 2 years old and in patients with thymic depletion, because they are on the age of vaccine administration according to the Cuban schedule and having affected a main organ for immune response might be a reason for them to show a deficient response and need special schedules

  2. Trivial trauma and delayed rupture of a normal spleen: a case report

    Directory of Open Access Journals (Sweden)

    Sowers Nicholas

    2011-12-01

    Full Text Available Abstract Introduction Although a majority of splenic ruptures present acutely with a known mechanism of injury, a minority of patients present days to weeks following trauma with a delayed rupture. Also uncommon is the atraumatic rupture, the vast majority of which occur in patients with underlying splenic pathology. A handful of cases of apparently spontaneous rupture of a normal spleen are reported; however, there is debate about whether these actually represent delayed ruptures following a history of trauma that is not elicited. Although a few cases of delayed rupture of the spleen following trivial trauma have been reported, the majority of these present evidence of an underlying disease process. We found only two such cases that documented a normal spleen and three cases where underlying splenic pathology was not reported. We review the literature and discuss the phenomenon of delayed rupture of the normal spleen following trivial trauma. Case presentation A 27-year-old Caucasian man with no underlying splenic pathology presented with splenic rupture one week after playfully wrestling with his partner. The patient did not present at the time of the injury and only recalled it upon repeated questioning after computed tomography diagnosis. Conclusions This case lends support to the theory that the normal spleen can rupture some time after trivial trauma, which seems like a more plausible explanation than rupture without cause. However, given the dearth of similar reports in the literature, the possibility remains that the association we have observed is not causational.

  3. Atheroprotector role of the spleen based on the teaching of Avicenna (Ibn Sina).

    Science.gov (United States)

    Emtiazy, Majid; Choopani, Rasool; Khodadoost, Mahmood; Tansaz, Mojgan; Nazem, Esmaiel

    2013-07-15

    Many studies have proven atherosclerosis is an inflammatory immune disease. The spleen plays an important immune role in the human body. Splenectomy is often used in several clinical disorders; but recent studies have shown that splenectomy may be effective in the development of atheroma lesions. Ibn Sina or Avicenna was known as one of the greatest philosopher and physician in Islam and in Medicine. He is remembered for his masterpiece, The "Al-Qanun fi al-Tibb" or "Qanun of medicine". According to the "Al-Qanun fi al-Tibb", spleen as storage organ plays an important role in absorption and secretion of the black bile in the human body. Therefore any disruption in the function of the spleen can lead to various diseases such as atherosclerosis. Based on his description, it is clear that Ibn Sina first described the role of spleen in prevention of atherosclerosis. In this review, we discuss the Avicenna (Ibn Sina) aspect of atheroprotector role of the spleen. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  4. Survival of motor neurone protein is required for normal postnatal development of the spleen.

    Science.gov (United States)

    Thomson, Alison K; Somers, Eilidh; Powis, Rachael A; Shorrock, Hannah K; Murphy, Kelley; Swoboda, Kathryn J; Gillingwater, Thomas H; Parson, Simon H

    2017-02-01

    Spinal muscular atrophy (SMA), traditionally described as a predominantly childhood form of motor neurone disease, is the leading genetic cause of infant mortality. Although motor neurones are undoubtedly the primary affected cell type, the severe infantile form of SMA (Type I SMA) is now widely recognised to represent a multisystem disorder where a variety of organs and systems in the body are also affected. Here, we report that the spleen is disproportionately small in the 'Taiwanese' murine model of severe SMA (Smn -/- ;SMN2 tg/0 ), correlated to low levels of cell proliferation and increased cell death. Spleen lacks its distinctive red appearance and presents with a degenerated capsule and a disorganised fibrotic architecture. Histologically distinct white pulp failed to form and this was reflected in an almost complete absence of B lymphocytes necessary for normal immune function. In addition, megakaryoctyes persisted in the red pulp. However, the vascular density remained unchanged in SMA spleen. Assessment of the spleen in SMA patients with the infantile form of the disease indicated a range of pathologies. We conclude that development of the spleen fails to occur normally in SMA mouse models and human patients. Thus, further analysis of immune function is likely to be required to fully understand the full extent of systemic disease pathology in SMA. © 2016 Anatomical Society.

  5. Factors influencing liver and spleen volume changes after donor hepatectomy for living donor liver transplantation

    International Nuclear Information System (INIS)

    Bae, Ji Hee; Ryeom, Hunku; Song, Jung Hup

    2013-01-01

    To define the changes in liver and spleen volumes in the early postoperative period after partial liver donation for living-donor liver transplantation (LDLT) and to determine factors that influence liver and spleen volume changes. 27 donors who underwent partial hepatectomy for LDLT were included in this study. The rates of liver and spleen volume change, measured with CT volumetry, were correlated with several factors. The analyzed factors included the indocyanine green (ICG) retention rate at 15 minutes after ICG administration, preoperative platelet count, preoperative liver and splenic volumes, resected liver volume, resected-to-whole liver volume ratio (LV R /LV W ), resected liver volume to the sum of whole liver and spleen volume ratio [LV R /(LV W + SV 0 )], and pre and post hepatectomy portal venous pressures. In all hepatectomy donors, the volumes of the remnant liver and spleen were increased (increased rates, 59.5 ± 50.5%, 47.9 ± 22.6%). The increment rate of the remnant liver volume revealed a positive correlation with LV R /LV W (r = 0.759, p R /LV W influences the increment rate of the remnant liver volume.

  6. Cotransport of bismerthiazol and montmorillonite colloids in saturated porous media

    Science.gov (United States)

    Shen, Chongyang; Wang, Hong; Lazouskaya, Volha; Du, Yichun; Lu, Weilan; Wu, Junxue; Zhang, Hongyan; Huang, Yuanfang

    2015-06-01

    While bismerthiazol [N,N‧-methylene-bis-(2-amino-5-mercapto-1,3,4-thiadiazole)] is one of the most widely used bactericides, the transport of bismerthiazol in subsurface environments is unclear to date. Moreover, natural colloids are ubiquitous in the subsurface environments. The cotransport of bismerthiazol and natural colloids has not been investigated. This study conducted laboratory column experiments to examine the transport of bismerthiazol in saturated sand porous media both in the absence and presence of montmorillonite colloids. Results show that a fraction of bismerthiazol was retained in sand and the retention was higher at pH 7 than at pH 4 and 10. The retention did not change with ionic strength. The retention was attributed to the complex of bismerthiazol with metals/metal oxides on sand surfaces through ligand exchange. The transport of bismerthiazol was enhanced with montmorillonite colloids copresent in the solutions and, concurrently, the transport of montmorillonite colloids was facilitated by the bismerthiazol. The transport of montmorillonite colloids was enhanced likely because the bismerthiazol and the colloids competed for the attachment/adsorption sites on collector surfaces and the presence of bismerthiazol changed the Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction energies between colloids and collectors. The transport of bismerthiazol was inhibited if montmorillonite colloids were pre-deposited in sand because bismerthiazol could adsorb onto the colloid surfaces. The adsorbed bismerthiazol could be co-remobilized with the colloids from primary minima by decreasing ionic strength. Whereas colloid-facilitated transport of pesticides has been emphasized, our study implies that transport of colloids could also be facilitated by the presence of pesticides.

  7. Pore-scale study of flow rate on colloid attachment and remobilization in a saturated micromodel

    NARCIS (Netherlands)

    Zhang, Qiulan; Raoof, A.; Hassanizadeh, S.M.

    2015-01-01

    Colloid attachment is an important retention mechanism. It is influenced by colloid size, pore size, and flow rate, among other factors. In this work, we studied colloid attachment experimentally under various flow rates, as well as colloid release in response to a rapid change of flow rate. Colloid

  8. Colloidal Dancers: Designing networks of DNA-functionalized colloids for non-random walks

    Science.gov (United States)

    Gehrels, Emily W.; Rogers, W. Benjamin; Zeravcic, Zorana; Manoharan, Vinothan N.

    2014-03-01

    We present experimental developments of a system of DNA-functionalized colloidal particles with the goal of creating directed motion (`dancing') along patterned substrates in response to temperature cycling. We take advantage of toehold exchange in the design of the DNA sequences that mediate the colloidal interactions to produce broadened, flat, or even re-entrant binding and unbinding transitions between the particles and substrate. Using this new freedom of design, we devise systems where, by thermal ratcheting, we can externally control the direction of motion and sequence of steps of the colloidal dancer. In comparison to DNA-based walkers, which move autonomously and whose motion is controlled by the substrate, our colloidal dancers respond to external driving, and their motion can be controlled in situ. Our use of DNA-functionalized colloidal particles instead of pure DNA systems also enables walking on the mesoscale in contrast to the molecular length scales previously demonstrated, allowing for the future prospect of directed transport over larger distances.

  9. Colloid-probe AFM studies of the interaction forces of proteins adsorbed on colloidal crystals.

    Science.gov (United States)

    Singh, Gurvinder; Bremmell, Kristen E; Griesser, Hans J; Kingshott, Peter

    2015-04-28

    In recent years, colloid-probe AFM has been used to measure the direct interaction forces between colloidal particles of different size or surface functionality in aqueous media, as one can study different forces in symmerical systems (i.e., sphere-sphere geometry). The present study investigates the interaction between protein coatings on colloid probes and hydrophilic surfaces decorated with hexagonally close packed single particle layers that are either uncoated or coated with proteins. Controlled solvent evaporation from aqueous suspensions of colloidal particles (coated with or without lysozyme and albumin) produces single layers of close-packed colloidal crystals over large areas on a solid support. The measurements have been carried out in an aqueous medium at different salt concentrations and pH values. The results show changes in the interaction forces as the surface charge of the unmodified or modified particles, and ionic strength or pH of the solution is altered. At high ionic strength or pH, electrostatic interactions are screened, and a strong repulsive force at short separation below 5 nm dominates, suggesting structural changes in the absorbed protein layer on the particles. We also study the force of adhesion, which decreases with an increment in the salt concentration, and the interaction between two different proteins indicating a repulsive interaction on approach and adhesion on retraction.

  10. Interaction between colloidal particles. Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    Longcheng Liu; Neretnieks, Ivars (Royal Inst. of Technology, Stockholm (Sweden). School of Chemical Science and Engineering, Dept. of Chemical Engineering and Technology)

    2010-02-15

    This report summarises the commonly accepted theoretical basis describing interaction between colloidal particles in an electrolyte solution. The two main forces involved are the van der Waals attractive force and the electrical repulsive force. The report describes in some depth the origin of these two forces, how they are formulated mathematically as well as how they interact to sometimes result in attraction and sometimes in repulsion between particles. The report also addresses how the mathematical models can be used to quantify the forces and under which conditions the models can be expected to give fair description of the colloidal system and when the models are not useful. This report does not address more recent theories that still are discussed as to their applicability, such as ion-ion correlation effects and the Coulombic attraction theory (CAT). These and other models will be discussed in future reports

  11. Collective motion in populations of colloidal robots

    Science.gov (United States)

    Bartolo, Denis; Bricard, Antoine; Caussin, Jean-Baptiste; Dauchot, Olivier; Desreumaux, Nicolas

    2014-03-01

    Could the behavior of bacteria swarms, fish schools, and bird flocks be understood within a unified framework? Can one ignore the very details of the interaction mechanisms at the individual level to elucidate how strikingly similar collective motion emerges at the group level in this broad range of motile systems? These seemingly provocative questions have triggered significant advance in the physics and the biology, communities over the last decade. In the physics language these systems, made of motile individuals, can all be though as different realizations of ``active matter.'' In this talk, I will show how to gain more insight into this vivid field using self-propelled colloids as a proxy for motile organism. I will show how to motorize colloidal particles capable of sensing the orientation of their neighbors. Then, I will demonstrate that these archetypal populations display spontaneous transitions to swarming motion, and to global directed motion with very few density and orientation fluctuations.

  12. Laser diffraction analysis of colloidal crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sogami, Ikuo S.; Shinohara, Tadatomi; Yoshiyama, Tsuyoshi [Kyoto Sangyo Univ., Department of Physics, Kyoto (Japan)

    2001-10-01

    Laser diffraction analysis is made on crystallization in salt-free aqueous suspensions of highly-charged colloidal particles for semi-dilute specimens of concentration 0.1-10.0 vol%. Kossel diffraction patterns which represent faithfully accurate information on lattice symmetries in the suspensions enable us to investigate the time evolution of colloidal crystals. The results show that the crystallization proceeds by way of the following intermediate phase transitions: two-dimensional hcp structure {yields} random layer structure {yields} layer structure with one sliding degree of freedom {yields} stacking disorder structure {yields} stacking structure with multivariant periodicity {yields} fcc twin structure with twin plane (111) {yields} normal fcc structure {yields} bcc twin structure with twin plane (11-bar2) or (1-bar12) {yields} normal bcc structure. For concentrated suspensions (>2 vol %), the phase transition ceases to proceed at the normal fcc structure. (author)

  13. Colloid transport code-nuclear user's manual

    International Nuclear Information System (INIS)

    Jain, R.

    1992-01-01

    This report describes the CTCN computer code, designed to solve the equations of transient colloidal transport of radionuclides in porous and fractured media. This Fortran 77 package solves systems of coupled nonlinear differential equations with a wide range of boundary conditions. The package uses the Method of Lines technique with a special section which forms finite-difference discretizations in up to four spatial dimensions to automatically convert the system into a set of ordinary differential equations. The CTCN code then solves these equations using a robust, efficient ODE solver. Thus CTCN can be used to solve population balance equations along with the usual transport equations to model colloid transport processes or as a general problem solver to treat up to four-dimensional differential systems

  14. Crust formation in drying colloidal suspensions

    KAUST Repository

    Style, R. W.

    2010-06-30

    During the drying of colloidal suspensions, the desiccation process causes the suspension near the air interface to consolidate into a connected porous matrix or crust. Fluid transport in the porous medium is governed by Darcy\\'s law and the equations of poroelasticity, while the equations of colloid physics govern processes in the suspension. We derive new equations describing this process, including unique boundary conditions coupling the two regions, yielding a moving-boundary model of the concentration and stress profiles during drying. A solution is found for the steady-state growth of a nedimensional crust during constant evaporation rate from the surface. The solution is used to demonstrate the importance of the system boundary conditions on stress profiles and diffusivity in a drying crust. © 2011 The Royal Society.

  15. Hybrid colloidal plasmonic-photonic crystals.

    Science.gov (United States)

    Romanov, Sergei G; Korovin, Alexander V; Regensburger, Alois; Peschel, Ulf

    2011-06-17

    We review the recently emerged class of hybrid metal-dielectric colloidal photonic crystals. The hybrid approach is understood as the combination of a dielectric photonic crystal with a continuous metal film. It allows to achieve a strong modification of the optical properties of photonic crystals by involving the light scattering at electronic excitations in the metal component into moulding of the light flow in series to the diffraction resonances occurring in the body of the photonic crystal. We consider different realizations of hybrid plasmonic-photonic crystals based on two- and three-dimensional colloidal photonic crystals in association with flat and corrugated metal films. In agreement with model calculations, different resonance phenomena determine the optical response of hybrid crystals leading to a broadly tuneable functionality of these crystals. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Particles with changeable topology in nematic colloids

    International Nuclear Information System (INIS)

    Ravnik, Miha; Čopar, Simon; Žumer, Slobodan

    2015-01-01

    We show that nematic colloids can serve as a highly variable and controllable platform for studying inclusions with changeable topology and their effects on the surrounding ordering fields. We explore morphing of toroidal and knotted colloidal particles into effective spheres, distinctively changing their Euler characteristic and affecting the surrounding nematic field, including topological defect structures. With toroidal particles, the inner nematic defect eventually transitions from a wide loop to a point defect (a small loop). Trefoil particles become linked with two knotted defect loops, mutually forming a three component link, that upon tightening transform into a two-component particle-defect loop link. For more detailed topological analysis, Pontryagin-Thom surfaces are calculated and visualised, indicating an interesting cascade of defect rewirings caused by the shape morphing of the knotted particles. (paper)

  17. Colloidal attraction induced by a temperature gradient.

    Science.gov (United States)

    Di Leonardo, R; Ianni, F; Ruocco, G

    2009-04-21

    Colloidal crystals are of extreme importance for applied research and for fundamental studies in statistical mechanics. Long-range attractive interactions, such as capillary forces, can drive the spontaneous assembly of such mesoscopic ordered structures. However, long-range attractive forces are very rare in the colloidal realm. Here we report a novel strong, long-ranged attraction induced by a thermal gradient in the presence of a wall. By switching the thermal gradient on and off, we can rapidly and reversibly form stable hexagonal 2D crystals. We show that the observed attraction is hydrodynamic in nature and arises from thermally induced slip flow on particle surfaces. We used optical tweezers to measure the force law directly and compare it to an analytical prediction based on Stokes flow driven by Marangoni-like forces.

  18. Viscoelasticity of colloidal polycrystals doped with impurities

    Science.gov (United States)

    Louhichi, Ameur; Tamborini, Elisa; Oberdisse, Julian; Cipelletti, Luca; Ramos, Laurence

    2015-09-01

    We investigate how the microstructure of a colloidal polycrystal influences its linear visco-elasticity. We use thermosensitive copolymer micelles that arrange in water in a cubic crystalline lattice, yielding a colloidal polycrystal. The polycrystal is doped with a small amount of nanoparticles, of size comparable to that of the micelles, which behave as impurities and thus partially segregate in the grain boundaries. We show that the shear elastic modulus only depends on the packing of the micelles and varies neither with the presence of nanoparticles nor with the crystal microstructure. By contrast, we find that the loss modulus is strongly affected by the presence of nanoparticles. A comparison between rheology data and small-angle neutron-scattering data suggests that the loss modulus is dictated by the total amount of nanoparticles in the grain boundaries, which in turn depends on the sample microstructure.

  19. Colloid Release From Differently Managed Loess Soil

    DEFF Research Database (Denmark)

    Vendelboe, Anders Lindblad; Schjønning, Per; Møldrup, Per

    2012-01-01

    The content of water-dispersible colloids (WDC) in a soil can have a major impact on soil functions, such as permeability to water and air, and on soil strength, which can impair soil fertility and workability. In addition, the content of WDC in the soil may increase the risk of nutrient loss...... and of colloid-facilitated transport of strongly sorbing compounds. In the present study, soils from the Bad Lauchstadt long-term static fertilizer experiment with different management histories were investigated to relate basic soil properties to the content of WDC, the content of water-stable aggregates (WSA......), and aggregate tensile strength. Our studies were carried out on soils on identical parent material under controlled management conditions, enabling us to study the long-term effects on soil physical properties with few explanatory variables in play. The content of WDC and the amount of WSA were measured...

  20. Ultrasmall colloidal PbS quantum dots

    International Nuclear Information System (INIS)

    Reilly, Nick; Wehrung, Michael; O'Dell, Ryan Andrew; Sun, Liangfeng

    2014-01-01

    Ultrasmall colloidal lead sulfide quantum dots can increase the open circuit voltages of quantum-dot-based solar cells because of their large energy gap. Their small size and visible or near infrared light-emitting property make them attractive to the applications of biological fluorescence labeling. Through a modified organometallic route, we can synthesize lead sulfide quantum dots as small as 1.6 nm in diameter. The low reaction temperature and the addition of a chloroalkane cosolvent decrease the reaction rate, making it possible to obtain the ultrasmall quantum dots. - Highlights: • Ultrasmall colloidal PbS quantum dots as small as 1.6 nm in diameter are synthesized. • The quantum dots emit red light with photoluminescence peak at 760 nm. • The growth temperature is as low as 50 °C. • Addition of cosolvent 1,2-dichloroethane in the reaction decreases the reaction rate

  1. Gray Correlation Analysis on the Relationship Between Colloidal Structure and Chemical Component of Asphalt Colloid and Performance

    Directory of Open Access Journals (Sweden)

    X. J. Cao

    2015-01-01

    Full Text Available Asphalt is considered a colloidal material and it is important to study the relationship between its colloidal structure, chemical components and performance. The aromatic nucleus content of asphalt at different depth analysed by attenuated total reflection (ATR was taken as the index of colloid structure. The gray correlation was used to analyse the relationship between colloidal structure and chemical components of asphalt gel and performance. The results show that the correlation degree between the index of colloidal structure and saturates and resins is high, which proves that saturates and resins play an important role in asphalt colloid structure. With regard to the asphalt performance indexes, the complex modulus G* and the tangent of the phase angle (tan δ have good correlation with the index of colloidal structure at the temperature of 30 – 70 °C but poor correlation at the temperature of 70 – 90 °C. Low temperature performance has a good correlation with colloid structure index, and tg can better reflect the characteristics of colloidal structure. The analysis shows that the colloidal structure of asphalt is a complex system and it is necessary to use more than one index to characterize the performance.

  2. Influence of biofilms on the movement of colloids in porous media. Implications for colloid facilitated transport in subsurface environments.

    Science.gov (United States)

    Leon Morales, Carlos Felipe; Strathmann, Martin; Flemming, Hans-Curt

    2007-05-01

    Colloid transport through porous media can be influenced by the presence of biofilms. Sterile and non-sterile sand columns were investigated using Laponite RD as model colloid and a highly mucoid strain of Pseudomonas aeruginosa as model biofilm former. Laponite RD was marked specifically by fluorescent complexes with rhodamine 6G. Breakthrough curves (BTCs) were used as parameters for determination of colloid transport characteristics. In the sterile columns, the colloid was mobile (collision efficiencies from 0.05 to 0.08) both after the presence of Na(+) and Ca(2+) ions followed by deionised water influent. In the biofilm-grown column, the same treatment did not result in colloid retention in the case of Na(+) exposure, but in altered or enhanced colloid transport. In the case of Ca(2+) ions exposure, colloid retention increased with biofilm age. After 3 weeks, almost complete retention was observed. Similar observations were made in columns packed with material from slow sand filtration units. These data reveal the complex interactions between biofilms, cations and colloid transport. Changes in the electrolyte composition of water percolating the subsurface can frequently occur and will result in different colloid transport characteristics with regard to the dominating species of ions and the relative abundance of microbial biofilms. This has to be considered when modelling colloid transport through the subsurface.

  3. Depleted Bulk Heterojunction Colloidal Quantum Dot Photovoltaics

    KAUST Repository

    Barkhouse, D. Aaron R.

    2011-05-26

    The first solution-processed depleted bulk heterojunction colloidal quantum dot solar cells are presented. The architecture allows for high absorption with full depletion, thereby breaking the photon absorption/carrier extraction compromise inherent in planar devices. A record power conversion of 5.5% under simulated AM 1.5 illumination conditions is reported. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. The Silicon:Colloidal Quantum Dot Heterojunction

    KAUST Repository

    Masala, Silvia

    2015-10-13

    A heterojunction between crystalline silicon and colloidal quantum dots (CQDs) is realized. A special interface modification is developed to overcome an inherent energetic band mismatch between the two semiconductors, and realize the efficient collection of infrared photocarriers generated in the CQD film. This junction is used to produce a sensitive near infrared photodetector. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Thermal Jamming of a Colloidal Glass

    KAUST Repository

    Agarwal, Praveen

    2011-12-01

    We investigate the effect of temperature on structure and dynamics of a colloidal glass created by tethering polymers to the surface of inorganic nanoparticles. Contrary to the conventional assumption, an increase in temperature slows down glassy dynamics of the material, yet causes no change in its static structure factor. We show that these findings can be explained within the soft glassy rheology framework if the noise temperature X of the glass phase is correlated with thermodynamic temperature. © 2011 American Physical Society.

  6. Changes of red blood cell aggregation parameters in a long-term follow-up of splenectomy, spleen-autotransplantation and partial or subtotal spleen resections in a canine model.

    Science.gov (United States)

    Miko, Iren; Nemeth, Norbert; Peto, Katalin; Furka, Andrea; Toth, Laszlo; Furka, Istvan

    2017-01-01

    Decrease or loss in splenic filtration function may influence the hemorheological state. To follow-up the long-term effects of splenectomy, spleen autotransplantation and spleen resections on red blood cell aggregation in a canine model. Beagle dogs were subjected to control (n = 6), splenectomy (SE, n = 4), spleen autotransplantation (AU, Furka's spleen-chip method, n = 8) or partial and subtotal spleen resection (n = 4/each) groups, and followed-up for 18 postoperative (p.o.) months. Erythrocyte aggregation was determined in parallel by light-transmittance aggregometry (Myrenne MA-1 aggregometer) and syllectometry (LoRRca). Erythrocyte aggregation decreased three months after splenectomy, with lower aggregation index and elongated aggregation time. It was more or less associated with relatively lower hematocrit and fibrinogen concentration. However, in autotransplantated animals a relatively higher fibrinogen did not increase the aggregation markedly. Spleen resection resulted in the most controversial red blood cell aggregation findings, and it seems, that the degree of the resection is an influencing factor. Splenectomy alters erythrocyte aggregation, spleen autotransplantation can be useful to preserve filtration function. However, the degree of restoration shows individual differences with a kind of 'functional periodicity'. Spleen resection controversially influences erythrocyte aggregation parameters. The subtotal resection is supposed to be worse than spleen autotransplantation.

  7. Transport of Intrinsic Plutonium Colloids in Saturated Porous Media

    Science.gov (United States)

    Zhou, D.; Abdel-Fattah, A.; Boukhalfa, H.; Ware, S. D.; Tarimala, S.; Keller, A. A.

    2011-12-01

    Actinide contaminants were introduced to the subsurface environment as a result of nuclear weapons development and testing, as well as for nuclear power generation and related research activities for defense and civilian applications. Even though most actinide species were believed to be fairly immobile once in the subsurface, recent studies have shown the transport of actinides kilometers away from their disposal sites. For example, the treated liquid wastes released into Mortandad Canyon at the Los Alamos National Laboratory were predicted to travel less than a few meters; however, plutonium and americium have been detected 3.4 km away from the waste outfall. A colloid-facilitated mechanism has been suggested to account for this unexpected transport of these radioactive wastes. Clays, oxides, organic matters, and actinide hydroxides have all been proposed as the possible mobile phase. Pu ions associated with natural colloids are often referred to as pseudo-Pu colloids, in contrast with the intrinsic Pu colloids that consist of Pu oxides. Significant efforts have been made to investigate the role of pseudo-Pu colloids, while few studies have evaluated the environmental behavior of the intrinsic Pu colloids. Given the fact that Pu (IV) has extremely low solubility product constant, it can be inferred that the transport of Pu in the intrinsic form is highly likely at suitable environmental conditions. This study investigates the transport of intrinsic Pu colloids in a saturated alluvium material packed in a cylindrical column (2.5-cm Dia. x 30-cm high) and compares the results to previous data on the transport of pseudo Pu colloids in the same material. A procedure to prepare a stable intrinsic Pu colloid suspension that produced consistent and reproducible electrokinetic and stability data was developed. Electrokinetic properties and aggregation stability were characterized. The Pu colloids, together with trillium as a conservative tracer, were injected into the

  8. Multidetector computed tomography findings of mesenteroaxial gastric volvulus combined with torsion of wandering spleen: A case report and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Youn, In Kyung; Ku, Young Mi; Lee, Su Lim [Dept. of Radiology, Uijeongbu St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu (Korea, Republic of)

    2016-05-15

    Gastric volvulus, defined as an abnormal rotation of stomach, may be idiopathic or secondary to abnormal fixation of intraperitoneal visceral ligaments. Wandering spleen is a movable spleen resulting from absence or underdevelopment of the splenic supporting ligaments that suspend the spleen to its normal position in the left part of the supramesocolic compartment of the abdomen. Wandering spleen increases the risk of splenic torsion. Both gastric volvulus and splenic torsion are potentially life-threatening if not urgently managed with surgery. Prompt and accurate diagnosis based on multidetector computed tomography (MDCT) is crucial to prevent unforeseen complications. Gastric volvulus and coexistent torsion of wandering spleen is a very rare condition. Herein, we described a case of gastric volvulus associated with wandering spleen and intestinal non-rotation in a 15-year-old girl focusing on MDCT findings.

  9. Shear-wave elastography of the liver and spleen identifies clinically significant portal hypertension

    DEFF Research Database (Denmark)

    Jansen, Christian; Bogs, Christopher; Verlinden, Wim

    2017-01-01

    BACKGROUND & AIMS: Clinically significant portal hypertension (CSPH) is associated with severe complications and decompensation of cirrhosis. Liver stiffness measured either by transient elastography (TE) or Shear-wave elastography (SWE) and spleen stiffness by TE might be helpful in the diagnosis...... of CSPH. We recently showed the algorithm to rule-out CSPH using sequential liver- (L-SWE) and spleen-Shear-wave elastography (S-SWE). This study investigated the diagnostic value of S-SWE for diagnosis of CSPH. METHODS: One hundred and fifty-eight cirrhotic patients with pressure gradient measurements...... were included into this prospective multicentre study. L-SWE was measured in 155 patients, S-SWE in 112 patients, and both in 109 patients. RESULTS: Liver-shear-wave elastography and S-SWE correlated with clinical events and decompensation. SWE of liver and spleen revealed strong correlations...

  10. A new procedure for imaging liver and spleen with water soluble contrast media in liposomes

    International Nuclear Information System (INIS)

    Zherbin, E.A.; Davidenkova, E.F.; Khanson, K.P.; Gubareva, A.V.; Zhdanova, N.V.; Aliyakparov, M.T.; Loshakova, L.V.; Fomina, Eh.V.; Rozenberg, O.A.

    1983-01-01

    The problems of long-term, reversible, and safe contrast investigation of liver and spleen and reduction of the irritating action of water-soluble contrast media on the wall of blood vessels are unresolved. The production and experimental application of contrast media encapsulated in liposomes are described. It is possible to produce a liposome preparation with 10-20 % Verografin content. After intravenous injection it leads to a quick (after 16-30 min), persisting (10-12 h) and reversible (24-30 h) contrast imaging of liver and spleen in rodents. The contrast medium has no pathological effects on heart, blood and circulatory system and on the morphology of liver, spleen, heart, lungs, kidneys and urinary bladder. The perspectives of clinical application of such contrast media are discussed. (author)

  11. Yersinia enterocolitica-associated generalized microinfarctions of bone and spleen in a child

    International Nuclear Information System (INIS)

    Reiss-Zimmermann, Martin; Sorge, Ina; Hirsch, Wolfgang; Schille, Regine; Beer, Joerg

    2007-01-01

    We report a case of unusual extraintestinal yersiniosis in a 16-year-old girl with generalized microinfarctions of the bone and spleen. For the past 2 years she had been repeatedly admitted to our hospital with reactive arthritis, erythema nodosum and iridocyclitis of unknown aetiology. Ultrasound showed multiple round hypoechoic lesions in the spleen that were shown to have low T2 signal on MRI. MRI also showed disseminated nodular lesions of the skeleton that were low T1 and high T2 signal and demonstrated inhomogeneous contrast enhancement. The patient is currently in good health on low-dose nonsteroidal immunosuppressive therapy. This is a unique case of microinfarctions of the skeleton and spleen caused by a severe postinfectious autoimmune reaction following extraintestinal Yersinia enterocolitica infection. (orig.)

  12. Yersinia enterocolitica-associated generalized microinfarctions of bone and spleen in a child

    Energy Technology Data Exchange (ETDEWEB)

    Reiss-Zimmermann, Martin; Sorge, Ina; Hirsch, Wolfgang [University Hospital Leipzig, Paediatric Radiology, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Schille, Regine [University Hospital Leipzig, Paediatric Department, Leipzig (Germany); Beer, Joerg [University of Leipzig, Institute for Medical Microbiology and Epidemiology of Infectious Diseases, Leipzig (Germany)

    2007-12-15

    We report a case of unusual extraintestinal yersiniosis in a 16-year-old girl with generalized microinfarctions of the bone and spleen. For the past 2 years she had been repeatedly admitted to our hospital with reactive arthritis, erythema nodosum and iridocyclitis of unknown aetiology. Ultrasound showed multiple round hypoechoic lesions in the spleen that were shown to have low T2 signal on MRI. MRI also showed disseminated nodular lesions of the skeleton that were low T1 and high T2 signal and demonstrated inhomogeneous contrast enhancement. The patient is currently in good health on low-dose nonsteroidal immunosuppressive therapy. This is a unique case of microinfarctions of the skeleton and spleen caused by a severe postinfectious autoimmune reaction following extraintestinal Yersinia enterocolitica infection. (orig.)

  13. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake ...

  14. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... type your comment or suggestion into the following text box: Comment: E-mail: Area code: Phone no: ... of a typical probe counter used for thyroid uptake exams. The patient sits with the camera directed at the neck for five minutes, and then the leg for ...

  15. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... of page Additional Information and Resources RTAnswers.org Radiation Therapy for Head and Neck Cancer top of page ... and Neck Cancer Treatment Radioactive Iodine (I-131) Therapy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear ... to Thyroid Scan and Uptake ...

  16. An evaporation model of colloidal suspension droplets

    Science.gov (United States)

    Sartori, Silvana; Li\\ Nán, Amable; Lasheras, Juan C.

    2009-11-01

    Colloidal suspensions of polymers in water or other solvents are widely used in the pharmaceutical industry to coat tablets with different agents. These allow controlling the rate at which the drug is delivered, taste or physical appearance. The coating is performed by simultaneously spraying and drying the tablets with the colloidal suspension at moderately high temperatures. The spreading of the coating on the pills surface depends on the droplet Webber and Reynolds numbers, angle of impact, but more importantly on the rheological properties of the drop. We present a model for the evaporation of a colloidal suspension droplet in a hot air environment with temperatures substantially lower than the boiling temperature of the carrier fluid. As the liquid vaporizes from the surface, a compacting front advances into the droplet faster than the liquid surface regresses, forming a shell of a porous medium where the particles reach their maximum packing density. While the surface regresses, the evaporation rate is determined by both the rate at which heat is transported to the droplet surface and the rate at which liquid vapor is diffused away from it. This regime continues until the compacting front reaches the center of the droplet, at which point the evaporation rate is drastically reduced.

  17. Patchy polymer colloids with tunable anisotropy dimensions.

    Science.gov (United States)

    Kraft, Daniela J; Hilhorst, Jan; Heinen, Maria A P; Hoogenraad, Mathijs J; Luigjes, Bob; Kegel, Willem K

    2011-06-09

    We present the synthesis of polymer colloids with continuously tunable anisotropy dimensions: patchiness, roughness, and branching. Our method makes use of controlled fusion of multiple protrusions on highly cross-linked polymer particles produced by seeded emulsion polymerization. Carefully changing the synthesis conditions, we can tune the number of protrusions, or branching, of the obtained particles from spheres with one to three patches to raspberry-like particles with multiple protrusions. In addition to that, roughness is generated on the seed particles by adsorption of secondary nucleated particles during synthesis. The size of the roughness relative to the smooth patches can be continuously tuned by the initiator, surfactant, and styrene concentrations. Seed colloids chemically different from the protrusions induce patches of different chemical nature. The underlying generality of the synthesis procedure allows for application to a variety of seed particle sizes and materials. We demonstrate the use of differently sized polyNIPAM (poly-N-isopropylacrylamide), as well as polystyrene and magnetite filled polyNIPAM seed particles, the latter giving rise to magnetically anisotropic colloids. The high yield together with the uniform, anisotropic shape make them interesting candidates for use as smart building blocks in self-assembling systems.

  18. C-cells in colloid goiter

    Directory of Open Access Journals (Sweden)

    Lima Marcus A.

    2003-01-01

    Full Text Available PURPOSE: The aim of this investigation was to quantitatively evaluate C-cells in colloid goiters, analyzing 36 thyroids that were obtained through thyroidectomy from 24 patients with goiter and 12 normal glands from adult patients without thyroid disease, which were used as the control group. MATERIAL AND METHODS: On average, 6 different thyroid areas were sampled and labeled by immunohistochemistry with a monoclonal anticalcitonin antibody, utilizing the avidin-biotin-peroxidase complex. C-cells were counted in fields measuring 1 square centimeter, and the mean number of cells per field was then calculated. Data were statistically analyzed using the Mann-Whitney test. RESULTS: In the colloid goiter group, the number of C-cells ranged from 0 to 23 per field, while in normal controls they ranged from 20 to 148 per field. CONCLUSIONS: These results demonstrate a significant decrease of C-cell number in the colloid goiter group compared with control group, indicating that the hyperplastic process is restricted to follicular cells, to the detriment of C-cells, which probably cease to receive trophic stimuli.

  19. Colloidal forming of metal/ceramic composites

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Herencia, A.J.; Gutierrez, C.A.; Millan, A.J.; Nieto, M.I.; Moreno, R. [Inst. de Ceramica y Vidrio, Madrid (Spain)

    2002-07-01

    Metal/Ceramic composites have very attractive properties as either structural or electronic materials. For certain applications, complex microstructures and shapes are required. Colloidal processing of ceramics has proved to provide better properties and allows to obtain near net complex shaped parts. However colloidal processing has not received a similar attention in powder metallurgy. This work deals with the colloidal approach to the forming of metallic and metal/ceramic composites in an aqueous medium. Rheological behavior of concentrated pure nickel, nickel/alumina and nickel/zirconia suspensions is studied and optimized for obtaining flat surfaces or near net shaped parts by tape casting and gel casting respectively. In each case the influence of the processing additives (acrylic binders for tape casting and carrageenans for gel casting) on the rheological behavior of the slurries is determined. Pure nickel and nickel/ceramic composites with different compositions have been prepared. Static and dynamic sintering studies were performed at different conditions in order to control the porosity and microstructure of the final bodies, which were characterized by optical microscopy. (orig.)

  20. Colloidal Switches by Electric and Magnetic Fields.

    Science.gov (United States)

    Demirörs, Ahmet Faik; Beltramo, Peter J; Vutukuri, Hanumantha Rao

    2017-05-24

    External electric and magnetic fields have already been proven to be a versatile tool to control the particle assembly; however, the degree of control of the dynamics and versatility of the produced structures is expected to increase if both can be implemented simultaneously. For example, while micromagnets can rapidly assemble superparamagnetic particles, repeated, rapid disassembly or reassembly is not trivial because of the remanence and coercivity of metals used in such applications. Here, an interdigitated design of micromagnet and microfabricated electrodes enables rapid switching of colloids between their magnetic and electric potential minima. Active control over colloids between two such adjacent potential minima enables a fast on/off mechanism, which is potentially important for optical switches or display technologies. Moreover, we demonstrate that the response time of the colloids between these states is on the order of tens of milliseconds, which is tunable by electric field strength. By carefully designing the electrode pattern, our strategy enables the switchable assembly of single particles down to few microns and also hierarchical assemblies containing many particles. Our work on precise dynamic control over the particle position would open new avenues to find potential applications in optical switches and display technologies.

  1. Armoring confined bubbles in concentrated colloidal suspensions

    Science.gov (United States)

    Yu, Yingxian; Khodaparast, Sepideh; Stone, Howard

    2016-11-01

    Encapsulation of a bubble with microparticles is known to significantly improve the stability of the bubble. This phenomenon has recently gained increasing attention due to its application in a variety of technologies such as foam stabilization, drug encapsulation and colloidosomes. Nevertheless, the production of such colloidal armored bubble with controlled size and particle coverage ratio is still a great challenge industrially. We study the coating process of a long air bubble by microparticles in a circular tube filled with a concentrated microparticles colloidal suspension. As the bubble proceeds in the suspension of particles, a monolayer of micro-particles forms on the interface of the bubble, which eventually results in a fully armored bubble. We investigate the phenomenon that triggers and controls the evolution of the particle accumulation on the bubble interface. Moreover, we examine the effects of the mean flow velocity, the size of the colloids and concentration of the suspension on the dynamics of the armored bubble. The results of this study can potentially be applied to production of particle-encapsulated bubbles, surface-cleaning techniques, and gas-assisted injection molding.

  2. Comparison of chromium and nickel uptake of plants grown in different soils

    Energy Technology Data Exchange (ETDEWEB)

    Vago, I. [University of Agriculture, Faculty of Agronomy, H-4015 Debrecen, P.O. Box 36 (Hungary); Gyoeri, Z. [University of Agriculture, Faculty of Agronomy, H-4015 Debrecen, P.O. Box 36 (Hungary); Loch, J. [University of Agriculture, Faculty of Agronomy, H-4015 Debrecen, P.O. Box 36 (Hungary)

    1996-03-01

    The chromium and nickel uptake of ryegrass has been examined in pot experiments in extremely different soils, poor sandy and fertile black chernozem. The effect of calcium carbonate doses and nitrogen supply on heavy metal uptake of the plant has been studied for chromium and nickel loadings (0-100 mg/kg Cr{sup 3+} or Ni{sup 2+}) applied as inorganic salts. The ability to uptake Cr{sup 3+} and Ni{sup 2+} differs significantly and is highly affected by the characteristics of soils, and depends on the metal investigated. The heavy metal uptake of the plant differs significantly in acid, colloid deficient sandy soils; while artificial chromium contamination did not modify the dry-matter production in the pots in either soil, a large quantity of nickel reduced the yields significantly. Nitrogen application did not change significantly the uptake of heavy metals. Lime application reduced the Ni{sup 2+} uptake of plants considerably, especially in sandy soil. In case of a calcium carbonate addition the dry-matter production of the plant was not affected by nickel. In chernozem soil the effect of lime application - i.e., the reduction of nickel uptake - was of a lesser degree. The significantly lesser Cr{sup 3+} uptake was further limited by a calcium carbonate application for both soils studied. A graphic presentation of these effects is given. (orig.). With 3 figs., 3 tabs.

  3. Design and elaboration of colloidal molecules: an overview.

    Science.gov (United States)

    Duguet, Etienne; Désert, Anthony; Perro, Adeline; Ravaine, Serge

    2011-02-01

    The concept of colloidal molecules was first evoked by van Blaaderen in 2003 for describing small non-spherical colloids made of the aggregation of a small number of particles. He predicted original properties to the complex assemblies of such colloids, in particular in optics. This critical review deals with the different strategies reported for creating robust clusters of spherical particles which could mimic the space-filling models of simple conventional molecules. These routes concern either the controlled clustering of preformed colloids directed by coalescence, physical routes, chemical routes, or 2-D/3-D geometrical confinement, or strategies starting from a single colloid which is decorated by satellite colloids by taking advantage of controlled phase separation or nucleation and growth phenomena. These routes are compared from the viewpoint of the accessible shapes, their tunability and scalability (146 references).

  4. Colloid migration in groundwaters: Geochemical interactions of radionuclides with natural colloids. 5. progress report

    International Nuclear Information System (INIS)

    Kim, J.I.; Delakowitz, B.; Zeh, P.; Probst, T.; Lin, X.; Ehrlicher, U.; Schauer, C.; Ivanovich, M.; Longworth, G.; Hasler, S.E.; Gardiner, M.; Fritz, P.; Klotz, D.; Lazik, D.; Wolf, M.; Geyer, S.; Alexander, J.L.; Read, D.; Thomas, J.B.

    1994-02-01

    The aim of the joint research programme is to determine the significance of groundwater colloids in far field radionuclide migration. The characterization, quantification and theoretical interpretation of colloid-borne transport phenomena of radionuclides in selected Gorleben aquifer systems are the main objectives of the present research programme. Gorleben aquifer systems are chosen because they are well characterized in terms of their hydrological and geological properties and because they contain substantial amounts of colloids of different chemical compositions as well as considerable quantities of chemical homologues and natural analogues of radionuclides, e.g. M(III), M(IV), M(VI), and Th and U decay series. The research tasks are investigated jointly by the four laboratories (listed below) in close coordination of experimental capacities of each laboratory. (orig.)

  5. Copper induced immunotoxicity promote differential apoptotic pathways in spleen and thymus

    International Nuclear Information System (INIS)

    Mitra, Soham; Keswani, Tarun; Ghosh, Nabanita; Goswami, Suranjana; Datta, Anuradha; Das, Salomie; Maity, Subhajit; Bhattacharyya, Arindam

    2013-01-01

    Highlights: ► Copper-induced ROS generation and mitochondrial trans-membrane potential changes result in different consequences in spleen and thymus. ► Inflammation appeared in both the spleen and thymus after to copper treatment. ► Apoptosis in the spleen appears to follow a p53-independent pathway. ► Apoptosis in the thymus appears to follow a p53-dependent intrinsic and extrinsic pathway. ► In both the spleen and thymus, the CD4+ T cell population decreased and CD8+ T cell population increased after copper treatment. - Abstract: Inorganic copper, such as that in drinking water and copper supplements, largely bypasses the liver and enters the free copper pool of the blood directly and that promote immunosuppression. Nevertheless, the signaling pathways underlying copper-induced immune cell death remains largely unclear. According to our previous in vivo report, to evaluate the further details of the apoptotic mechanism, we have investigated how copper regulates apoptotic pathways in spleen and thymus. We have analyzed different protein expression by western blotting and immunohistochemistry and mRNA expression by RT-PCR and gel electrophoresis. We also have measured mitochondrial trans-membrane potential, ROS and CD4 + and CD8 + population by flow cytometry. Sub lethal doses of copper in spleen and thymus of in vivo Swiss albino mice promote different apoptotic pathways. In case of spleen, ROS generation and mitochondrial trans-membrane potential changes promotes intrinsic pathway of apoptosis that was p53 independent, ultimately leads to decrease in CD4 + T cell population and increase in CD8 + T cell population. However in case of thymus, ROS generation and mitochondrial trans-membrane potential changes lead to death receptor that regulate extrinsic and intrinsic pathways of apoptosis and the apoptotic mechanism which was p53 dependent. Due to copper treatment, thymic CD4 + T cell population decreased and CD8 + T cell population was increased or

  6. Reactive Hypertrophy of an Accessory Spleen Mimicking Tumour Recurrence of Metastatic Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Christin Tjaden

    2011-01-01

    Full Text Available De novo occurrence of an accessory spleen after splenectomy is worth noting for two reasons. First, it is known that splenectomy can cause reactive hypertrophy of initially inactive and macroscopically invisible splenic tissue. Second, it can mimic tumour recurrence in situations in which splenectomy has been performed for oncological reasons. This might cause difficulties in differential diagnosis and the clinical decision for reoperation. We report the case of a patient with suspected recurrence of renal cell carcinoma after total pancreatectomy and splenectomy for metastatic renal cell carcinoma, which finally revealed an accessory spleen as the morphological correlate of the newly diagnosed mass in the left retroperitoneum.

  7. Effect of rapamycin on spleen size in longstanding renal transplant recipients.

    Science.gov (United States)

    Araújo, N C; Sampaio Gonçalves de Lucena, S B; da Silveira Rioja, S

    2014-06-01

    Based on evidence available in the literature, rapamycin, a mammalian target of rapamycin (mTOR) inhibitor, but not calcineurin inhibitors (CNIs), has been shown to decrease spleen size. Small spleen, in some instances, is associated with hyposplenism, a condition recently reported in patients with longstanding renal transplant. Accordingly, the effect of immunosuppressive drugs on spleen size was evaluated. Renal transplant recipients (35 taking mTOR and 68 CNI) were included, in whom a standardized investigation of the kidney allograft and spleen with the use of color Doppler ultrasound was performed and a peripheral smear were reviewed for the presence of Howell-Jolly bodies (HJBs). We enrolled 103 patients (64 men; 66 from a deceased donor). The mean age was 47.7 years (range, 23.0-74.0 y). Mean transplant duration was 1,899 days (range, 181-6,883 d). According to the presence of HJBs, the prevalence of hyposplenism was 47.6% for the entire cohort. The differences between the mTOR and CNI groups regarding sex and the presence of HJBs were not statistically significant (P > .05). Age, creatinine, hemoglobin, leukocytes, platelets, and Doppler parameters in spleen and kidney were similar in both groups (P > .05). mTOR patients had a decreased spleen length size (90.09 ± 13.02 mm vs 111.95 ± 18.66 mm; P < .001), a longer transplant duration (3,576 ± 1,594 d vs 1,036 ± 1,369 d; P < .001) and higher serum cholesterol (227.50 ± 38.75 mg/dL vs 182.67 ± 37.74 mg/dL; P < .001) and triglycerides (194.23 ± 79.88 mg/dL vs 148.70 ± 55.54 mg/dL; P = .003) levels compared with the CNI group. A multivariate analysis showed mTOR inhibitor to be the most important predictor of spleen size. In both the mTOR and CNI groups, the comparison between the subgroups of present and absent HJBs did not show any difference. The findings of this study suggest that small spleens in transplant recipients may be linked to treatment with an mTOR inhibitor, although this apparently does

  8. Determination of T1- and T2-relaxation times in the spleen of patients with splenomegaly

    DEFF Research Database (Denmark)

    Thomsen, C; Josephsen, P; Karle, H

    1990-01-01

    Twenty-nine patients with known splenomegaly and seven healthy volunteers were examined. The T1 and T2 relaxation times were read out from a region of interest centrally in the spleen. Even though different mean T1 and T2 relaxation times were found between the groups, the great scatter and the c......Twenty-nine patients with known splenomegaly and seven healthy volunteers were examined. The T1 and T2 relaxation times were read out from a region of interest centrally in the spleen. Even though different mean T1 and T2 relaxation times were found between the groups, the great scatter...

  9. Shape Separation of Colloidal Metal Nanoparticles via Size Exclusion Chromatography

    OpenAIRE

    Marvi, Sarrah

    2016-01-01

    The inherent polydispersity of solution-based, colloidal nanoparticle syntheses has necessitated the development of facile post-processing methods for the purification of anisotropic nanoparticles. Here, the use of size exclusion chromatography is explored for the shape separation of colloidal silver nanocube and colloidal gold bipyramid solutions. Multiple column packing materials, pore sizes, and mobile phases were tested to address the prevalent issues of metal adsorption to the high surfa...

  10. Colloids dragged through a polymer solution: experiment, theory and simulation

    OpenAIRE

    Gutsche, Christof; Kremer, Friedrich; Krüger, Matthias; Rauscher, Markus; Weeber, Rudolf; Harting, Jens

    2007-01-01

    We present micro-rheological measurments of the drag force on colloids pulled through a solution of lambda-DNA (used here as a monodisperse model polymer) with an optical tweezer. The experiments show a violation of the Stokes-Einstein relation based on the independently measured viscosity of the DNA solution: the drag force is larger than expected. We attribute this to the accumulation of DNA infront of the colloid and the reduced DNA density behind the colloid. This hypothesis is corroborat...

  11. Reduced Noradrenergic Signaling in the Spleen Capsule in the Absence of CB1and CB2Cannabinoid Receptors.

    Science.gov (United States)

    Simkins, Tyrell J; Fried, David; Parikh, Kevin; Galligan, James J; Goudreau, John L; Lookingland, Keith J; Kaplan, Barbara L F

    2016-12-01

    The spleen is a visceral organ that contracts during hypoxia to expel erythrocytes and immune cells into the circulation. Spleen contraction is under the control of noradrenergic sympathetic innervation. The activity of noradrenergic neurons terminating in the spleen capsule is regulated by α2-adrenergic receptors (AR). Interactions between endogenous cannabinoid signaling and noradrenergic signaling in other organ systems suggest endocannabinoids might also regulate spleen contraction. Spleens from mice congenitally lacking both CB 1 and CB 2 cannabinoid receptors (Cnr1 -/- /Cnr2 -/- mice) were used to explore the role of endocannabinoids in spleen contraction. Spleen contraction in response to exogenous norepinephrine (NE) was found to be significantly lower in Cnr1 -/- /Cnr2 -/- mouse spleens, likely due to decreased expression of capsular α1AR. The majority of splenic Cnr1 mRNA expression is by cells of the spleen capsule, suggestive of post-synaptic CB 1 receptor signaling. Thus, these studies demonstrate a role for CB 1 and/or CB 2 in noradrenergic splenic contraction.

  12. Automatized spleen segmentation in non-contrast-enhanced MR volume data using subject-specific shape priors

    Science.gov (United States)

    Gloger, Oliver; Tönnies, Klaus; Bülow, Robin; Völzke, Henry

    2017-07-01

    To develop the first fully automated 3D spleen segmentation framework derived from T1-weighted magnetic resonance (MR) imaging data and to verify its performance for spleen delineation and volumetry. This approach considers the issue of low contrast between spleen and adjacent tissue in non-contrast-enhanced MR images. Native T1-weighted MR volume data was performed on a 1.5 T MR system in an epidemiological study. We analyzed random subsamples of MR examinations without pathologies to develop and verify the spleen segmentation framework. The framework is modularized to include different kinds of prior knowledge into the segmentation pipeline. Classification by support vector machines differentiates between five different shape types in computed foreground probability maps and recognizes characteristic spleen regions in axial slices of MR volume data. A spleen-shape space generated by training produces subject-specific prior shape knowledge that is then incorporated into a final 3D level set segmentation method. Individually adapted shape-driven forces as well as image-driven forces resulting from refined foreground probability maps steer the level set successfully to the segment the spleen. The framework achieves promising segmentation results with mean Dice coefficients of nearly 0.91 and low volumetric mean errors of 6.3%. The presented spleen segmentation approach can delineate spleen tissue in native MR volume data. Several kinds of prior shape knowledge including subject-specific 3D prior shape knowledge can be used to guide segmentation processes achieving promising results.

  13. Spectroscopic studies on colloid-borne uranium

    International Nuclear Information System (INIS)

    Ulrich, K.U.; Weiss, S.; Foerstendorf, H.; Brendler, V.; Zaenker, H.; Rossberg, A.; Scheinost, A.C.

    2005-01-01

    Full text of publication follows: Information on molecular speciation provides a basis for the reliable assessment of actinide migration in the environment. We use several methods for the separation of colloids from liquids (e.g. ultracentrifugation, ultrafiltration) in combination with spectroscopic techniques (EXAFS, ATR-FTIR, Moessbauer) and modeling of surface complexation reactions. This enables us to investigate the speciation of colloid-borne uranium in waters occurring in or escaping from abandoned uranium mines during the remediation process. Mine flooding was simulated on a 100 L scale by mixing acid mine water of elevated U concentration with oxic, near-neutral groundwater until pH ∼ 5.5 was reached. The freshly formed colloids adsorbed 95% of the total uranium and consisted mainly of 2-line ferri-hydrite (Fh) besides traces of aluminum, sulfur, silica, and carbon compounds. EXAFS analysis at the U-LIII absorption edge suggested a bidentate surface complex of UO 2 2+ on FeO 6 octahedra, but two minor backscattering contributions in close vicinity to the absorber remained unexplained. Since only Al could be excluded as backscattering atom, we studied U sorption on Fh at pH 5.5 in presence and in absence of sulfate, silicate, and atmospheric CO 2 to clarify the bond structure. EXAFS showed the unknown backscattering contributions in all the sorption samples regardless of the presence or absence of the tested components. Contrary to structural models proposed in the literature, bi-dentately complexed carbonate ligands do not explain our experimental EXAFS data. But ATR-IR spectra showed that U-carbonato complexes must be involved in the sorption of uranyl on Fh. These results are not contradictory if the carbonate ligands were bound mono-dentately. Nevertheless, carbon cannot act as backscattering atom in carbonate-free samples prepared in N 2 atmosphere. We propose a new structural model including exclusively Fe, H, and O atoms in which the bi

  14. Giant Leaking Colloid Cyst Presenting with Aseptic Meningitis

    DEFF Research Database (Denmark)

    Bakhtevari, Mehrdad Hosseinzadeh; Sharifi, Guive; Jabbari, Reza

    2015-01-01

    BACKGROUND: Colloid cysts are benign third ventricle lesions that need to be diagnosed correctly because of their association with sudden death. Chemical or aseptic meningitis is a rare presentation of a colloid cyst. METHODS: We present a case of a 69-year-old man with fever, alteration of mental...... status, and meningismus. Microbiological examination of the cerebrospinal fluid revealed aseptic meningitis. Brain imaging revealed a third ventricular colloid cyst with hydrocephalus. RESULTS: The tumor was resected via endoscopic intervention. There were no persistent operative complications related...... to the endoscopic procedure. CONCLUSIONS: Chemical or aseptic meningitis is an unusual clinical manifestation of a colloid cyst, complicating the differential diagnosis, especially in the elderly....

  15. Effective electrostatic interactions in colloid-nanoparticle mixtures

    Science.gov (United States)

    Denton, Alan R.

    2017-12-01

    Interparticle interactions and bulk properties of colloidal suspensions can be substantially modified by the addition of nanoparticles. Extreme asymmetries in size and charge between colloidal particles and nanoparticles present severe computational challenges to molecular-scale modeling of such complex systems. We present a statistical mechanical theory of effective electrostatic interactions that can greatly ease large-scale modeling of charged colloid-nanoparticle mixtures. By applying a sequential coarse-graining procedure, we show that a multicomponent mixture of charged colloids, nanoparticles, counterions, and coions can be mapped first onto a binary mixture of colloids and nanoparticles and then onto a one-component model of colloids alone. In a linear-response approximation, the one-component model is governed by a single effective pair potential and a one-body volume energy, whose parameters depend nontrivially on nanoparticle size, charge, and concentration. To test the theory, we perform molecular dynamics simulations of the two-component and one-component models and compute structural properties. For moderate electrostatic couplings, colloid-colloid radial distribution functions and static structure factors agree closely between the two models, validating the sequential coarse-graining approach. Nanoparticles of sufficient charge and concentration enhance screening of electrostatic interactions, weakening correlations between charged colloids and destabilizing suspensions, consistent with experiments.

  16. Sodium meta-autunite colloids: Synthesis, characterization,stability

    Energy Technology Data Exchange (ETDEWEB)

    zzuoping@lbl.gov

    2004-04-10

    Waste forms of U such as those in the United States Department of Energy's Hanford Site often contain high concentrations of Na and P. Low solubility sodium uranyl phosphates such as sodium meta-autunite have the potential to form mobile colloids that can facilitate transport of this radionuclide. In order to understand the geochemical behavior of uranyl phosphate colloids, we synthesized sodiummeta-autunite colloids, and characterized their morphology, chemical composition, structure, dehydration, and surface charge. The stability of these synthetic plate-shaped colloids was tested with respect to time and pH. The highest aggregation rate was observed at pH 3, and the rate decreases as pH increases, indicating that higher stability of colloid dispersion under neutral and alkaline pH conditions. The synthetic colloids are all negatively charged and no isoelectric points were found over a pH range of 3 to 9. The zeta-potentials of the colloids in the phosphate solution show a strong pH-dependence in the more acidic range over time, but are relatively constant in the neutral and alkaline pH range. The geochemical behavior of the synthetic colloids can be interpreted using DLVO theory. The results suggest that formation of mobile sodium meta-autunite colloids can enhance the transport of U in some contaminated sediments.

  17. Morphological deformation during evaporation induced assembly of mixed colloidal suspension

    Science.gov (United States)

    Sen, D.; Melo, J. S.; Bahadur, J.; Mazumder, S.; Bhattacharya, S.; D'Souza, S. F.

    2010-12-01

    Sphere to deformed doughnut type transformation of colloidal droplets during evaporation induced assembly of colloidal silica and E. coli was observed. Distortion modulations get amplified with increase in volume fraction of anisotropic soft colloidal component. Reduction in elastic constants of formed shell, at the boundary of a drying droplet, and the anisotropic nature of bacterial component facilitate the deformation process. The charge modification of E. coli surface by Poly cationic Polytheleneimine ceases the morphological transformation and results spherical assembled grains. Hierarchical structures of these assembled colloidal grains have been probed using electron microscopy and small- angle neutron scattering techniques.

  18. Partial structure factors in star polymer/colloid mixtures

    CERN Document Server

    Stellbrink, J; Richter, D; Moussaid, A; Schofield, A B; Poon, W C K; Pusey, P N; Lindner, P; Dzubiella, J; Likos, C N; Löwen, H

    2002-01-01

    Addition of polymer to colloidal suspensions induces an attractive part to the colloid pair potential, which is of purely entropic origin (''depletion interaction''). We investigated the influence of polymer branching on depletion forces by studying mixtures of hard sphere colloids and star polymers with increasing arm number f=2-32, but constant R sub g approx 500 A. We found a pronounced effect of branching on the position of the gas/liquid demixing transition. Using small angle neutron scattering (SANS) we were able to measure partial structure factors in star polymer/colloid mixtures. The relative distance to the demixing transition is reflected in our scattering data. (orig.)

  19. Infrared colloidal lead chalcogenide nanocrystals: synthesis, properties, and photovoltaic applications.

    Science.gov (United States)

    Fu, Huiying; Tsang, Sai-Wing

    2012-04-07

    Simple solution phase, catalyst-free synthetic approaches that offer monodispersed, well passivated, and non-aggregated colloidal semiconductor nanocrystals have presented many research opportunities not only for fundamental science but also for technological applications. The ability to tune the electrical and optical properties of semiconductor nanocrystals by manipulating the size and shape of the crystals during the colloidal synthesis provides potential benefits to a variety of applications including photovoltaic devices, light-emitting diodes, field effect transistors, biological imaging/labeling, and more. Recent advances in the synthesis and characterization of colloidal lead chalcogenide nanocrystals and the achievements in colloidal PbS or PbSe nanocrystals solar cells have demonstrated the promising application of infrared-emitting colloidal lead chalcogenide nanocrystals in photovoltaic devices. Here, we review recent progress in the synthesis and optical properties of colloidal lead chalcogenide nanocrystals. We focus in particular upon the size- and shape-controlled synthesis of PbS, PbSe, and PbTe nanocrystals by using different precursors and various stabilizing surfactants for the growth of the colloidal nanocrystals. We also summarize recent advancements in the field of colloidal nanocrystals solar cells based on colloidal PbS and PbSe nanocrystals. This journal is © The Royal Society of Chemistry 2012

  20. Statics and dynamics of colloidal particles on optical tray arrays

    Energy Technology Data Exchange (ETDEWEB)

    Reichardt, Charles [Los Alamos National Laboratory; Reichhardt, Cynthia J [Los Alamos National Laboratory

    2009-01-01

    We examine the statics and dynamics of charged colloids interacting with periodic optical trap arrays. In particular we study the regime where more than one colloid is confined in each trap, creating effective dimer, trimer, and higher order states called colloidal molecular crystals. The n-mer states have all effective orientational degree of freedom which can be controlled with an external driving field. In general, the external field causes a polarization effect where the orientation of the n-mers aligns with the external field, similar to liquid crystal systems. Additionally, under a rotating external drive the n-mers can rotate with the drive. In some cases a series of structural transitions in the colloidal crystal states occur in the rotating field due to a competition between the ordering of the colloidal molecular crystals and the polarization effect which orients the n-mers in the direction of the drive. We also show that for some parameters, the n-mers continuously rotate with the drive without witching, that depinning transitions can occur where the colloids jump from well to well, and that there are a number of distinct dynamical transitions between the phases. Finally, we illustrate colloidal orderings at fillings of more than four colloids per trap, indicating that it is possible to create higher order colloidal crystal cluster phases.

  1. An agglomeration-based model for colloid filtration.

    Science.gov (United States)

    Chatterjee, Jaideep; Gupta, Santosh Kumar

    2009-05-15

    This paper develops a model for colloid filtration which accounts for the possibility of aggregation of the colloidal particles in the aqueous phase. Depth-wise variation of liquid-phase colloid concentration, C(x), is measured experimentally in the presence of monovalent cations at different concentrations and divalent cations, which confirm that log of C(x) deviates significantly from linearity for all of the above cases. It is also observed that in all systems showing significant removal, preaggregation of the colloids is observed, which confirms the correlation between aggregation of colloids with their retention in saturated porous media, which has been reported earlier. A new model for depth filtration which is based on material balances of the different sized aggregates, which could be present in the colloidal dispersion, is developed. This resulting model, based on differential deposition rates for different sized aggregates, shows good match with the experimentally observed variation of C(x) with depth, for all of the above conditions. A method for estimating model parameters from data is developed. This model remains independent of the actual deposition mechanism, which could be secondary minima attachment of these colloidal aggregates or the entrapment of these colloidal aggregates in regions of confined geometry. This model can be extended to predict the transport of colloids in groundwater.

  2. Infrared colloidal lead chalcogenide nanocrystals: Synthesis, properties, and photovoltaic applications

    Science.gov (United States)

    Fu, Huiying; Tsang, Sai-Wing

    2012-03-01

    Simple solution phase, catalyst-free synthetic approaches that offer monodispersed, well passivated, and non-aggregated colloidal semiconductor nanocrystals have presented many research opportunities not only for fundamental science but also for technological applications. The ability to tune the electrical and optical properties of semiconductor nanocrystals by manipulating the size and shape of the crystals during the colloidal synthesis provides potential benefits to a variety of applications including photovoltaic devices, light-emitting diodes, field effect transistors, biological imaging/labeling, and more. Recent advances in the synthesis and characterization of colloidal lead chalcogenide nanocrystals and the achievements in colloidal PbS or PbSe nanocrystals solar cells have demonstrated the promising application of infrared-emitting colloidal lead chalcogenide nanocrystals in photovoltaic devices. Here, we review recent progress in the synthesis and optical properties of colloidal lead chalcogenide nanocrystals. We focus in particular upon the size- and shape-controlled synthesis of PbS, PbSe, and PbTe nanocrystals by using different precursors and various stabilizing surfactants for the growth of the colloidal nanocrystals. We also summarize recent advancements in the field of colloidal nanocrystals solar cells based on colloidal PbS and PbSe nanocrystals.

  3. Oppositely charged colloids out of equilibrium

    Science.gov (United States)

    Vissers, T.

    2010-11-01

    Colloids are particles with a size in the range of a few nanometers up to several micrometers. Similar to atomic and molecular systems, they can form gases, liquids, solids, gels and glasses. Colloids can be used as model systems because, unlike molecules, they are sufficiently large to be studied directly with light microscopy and move sufficiently slow to study their dynamics. In this thesis, we study binary systems of polymethylmethacrylate (PMMA) colloidal particles suspended in low-polar solvent mixtures. Since the ions can still partially dissociate, a surface charge builds up which causes electrostatic interactions between the colloids. By carefully tuning the conditions inside the suspension, we make two kinds of particles oppositely charged. To study our samples, we use Confocal Laser Scanning Microscopy (CLSM). The positively and negatively charged particles can be distinguished by a different fluorescent dye. Colloids constantly experience a random motion resulting from random kicks of surrounding solvent molecules. When the attractions between the oppositely charged particles are weak, the particles can attach and detach many times and explore a lot of possible configurations and the system can reach thermodynamic equilibrium. For example, colloidal ‘ionic’ crystals consisting of thousands to millions of particles can form under the right conditions. When the attractions are strong, the system can become kinetically trapped inside a gel-like state. We observe that when the interactions change again, crystals can even emerge again from this gel-like phase. By using local order parameters, we quantitatively study the crystallization of colloidal particles and identify growth defects inside the crystals. We also study the effect of gravity on the growth of ionic crystals by using a rotating stage. We find that sedimentation can completely inhibit crystal growth and plays an important role in crystallization from the gel-like state. The surface

  4. Biogeochemical Factors Influencing the Transport and Fate of Colloids and Colloid-Associated Contaminants in the Vadose Zone

    Science.gov (United States)

    Bradford, S. A.

    2016-12-01

    The vadose zone exhibits large spatial and temporal variability in many physical, chemical, and biological factors that strongly influence the transport and fate of colloids (e.g., microbes, nanoparticles, clays, and dissolved organic matter) and colloid-associated contaminants (e.g., heavy metals, radionuclides, pesticides, and antibiotics). This presentation highlights our research activities to better understand and predict the influence of specific biogeochemical processes on colloid and colloid-facilitated transport. Results demonstrate the sensitivity of colloid transport, retention, release, and clogging to transients in solution chemistry (e.g., ionic strength, pH, cation and anion type, and surfactants), water velocity and saturation, and preferential flow. Mathematical modeling at interface-, pore-, and continuum-scales is shown to be a critical tool to quantify the relative importance and coupling of these biogeochemical factors on colloid and contaminant transport and fate, which otherwise might be experimentally intractable. Existing gaps in knowledge and model limitations are identified.

  5. Radiopharmaceutical cellular uptake mechanisms

    International Nuclear Information System (INIS)

    Stefanescu, Cipriana; Rusu, V.

    1996-01-01

    Cellular radiopharmaceutical specificity depends mainly of the uptake mechanisms. Usually, this can be one of the classical membrane transport type (a passive or active transport, a receptor mediated one or a combination of them). It can also be an electrochemical gradient dependent membrane transport in relation with Nernst equation, as in case of 99m Tc MIBI, the representative molecule of a widely studied family tracers, with applications in cardiac and oncological scintigraphy. Another mechanism can be an ATP dependent active transport, that results in the most important 201 Tl inflow. 201 Tl inflow is also an example of multiple mechanisms involved in cellular ionic inflow. Over 30% of 201 Tl transport imply other ways, like Na + - K + - Cl - co-transport. For a given tracer, the mechanism may depend also on the cell type. In conclusion, knowledge of the radiotracer uptake mechanisms allows finding the 'ideal' radiotracer with high specificity for the tissue to be visualized. (authors)

  6. Recombinant Protein Polymers for Colloidal Stabilization and Improvement of Cellular Uptake of Diamond Nanosensors

    NARCIS (Netherlands)

    Zheng, Tingting; Martinez, Felipe Perona; Storm, Ingeborg Maria; Rombouts, Wolf; Sprakel, Joris; Schirhagl, Romana; de Vries, Renko

    2017-01-01

    Fluorescent nanodiamonds are gaining increasing attention as fluorescent labels in biology in view of the fact that they are essentially nontoxic, do not bleach, and can be used as nanoscale sensors for various physical and chemical properties. To fully realize the nanosensing potential of

  7. Determination of normal dimension of the spleen by ultrasound in an ...

    African Journals Online (AJOL)

    Materials and Methods: A prospective study of normal spleen ultrasound-based measurements in 200 Nigerian adults at the University of Benin Teaching Hospital Benin, Nigeria. Results: There were 91 males and 109 females; their age ranged between 20 and 60 years. For the males the mean age was 32.4 years (± 9.2 ...

  8. The involvement of the spleen during chronic phase of Schistosoma mansoni infection in galectin-3-/- mice.

    Science.gov (United States)

    Brand, Camila; Oliveira, Felipe L; Takiya, Christina M; Palumbo, Antônio; Hsu, Daniel K; Liu, Fu-Tong; Borojevic, Radovan; Chammas, Roger; El-Cheikh, Márcia C

    2012-08-01

    Schistosoma mansoni synthesizes glycoconjugates which interact with galectin-3, eliciting an intense humoral immune response. Moreover, it was demonstrated that galectin-3 regulates B cell differentiation into plasma cells. Splenomegaly is a hallmark event characterized by polyclonal B cell activation and enhancement of antibody production. Here, we investigated whether galectin-3 interferes with spleen organization and B cell compartment during chronic schistosomiasis, using wild type (WT) and galectin-3-/- mice. In chronically-infected galectin-3-/- mice the histological architecture of the spleen, including white and red pulps, was disturbed with heterogeneous lymphoid follicles, an increased number of plasma cells (CD19-B220-/lowCD138+) and a reduced number of macrophages (CD19-B220-Mac-1+CD138-) and B lymphocytes (CD19+B220+/highCD138-), compared with the WT infected mice. In the absence of galectin-3 there was an increase of annexin-V+PI- cells and a major presence of apoptotic cells in spleen compared with WT infected mice. In spleen of WT infected mice galectin-3 was largely expressed in lymphoid follicles and extrafollicular sites. Thus, we propose that galectin-3 plays a role in splenic architecture, controlling distinct events such as apoptosis, macrophage activity, B cell differentiation and plasmacytogenesis in the course of S. mansoni infection.

  9. Amelioratory Effect of Nanoconjugated Vancomycin on Spleen during VRSA-Induced Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Subhankari Prasad Chakraborty

    2011-01-01

    Full Text Available Objective. The aim of the present study was to evaluate the possible antioxidant effects of nanoconjugated vancomycin against VRSA infection on select makers of oxidative damage and antioxidant status in spleen. Methods. A coagulase-positive VRSA strain was used for this study. VRSA infection was developed in Swiss mice by intraperitoneal injection of 5 × 106 CFU/mL bacterial solutions. VRSA-infected mice were treated with nanoconjugated vancomycin at its effective dose for 10 days. After decapitation, blood was used for determination of viable bacteria count and spleen was excised from control and experimental groups, homogenized and used for different biochemical estimations. Results. Nitrate level, myeloperoxidase activity, lipid peroxidation, protein oxidation, oxidized glutathione, and DNA fragmentation level were increased significantly (P<0.05 in spleen of VRSA-infected group as compared to control group, and reduced glutathione level, activity of SOD, CAT, GPx, GR, and GST were decreased significantly (P<0.05; which were increased or decreased significantly (P<0.05 near to normal in nanoconjugated vancomycin-treated group. Conclusion. These findings suggest the potential use and beneficial role of nanoconjugated vancomycin against VRSA-infection-induced oxidative stress and DNA damage in spleen.

  10. Spontaneous rupture of the spleen – a rare and potentially fatal ...

    African Journals Online (AJOL)

    Following prompt and aggressive surgical intervention, both mother and baby survived. S Afr J Obstet Gynaecol 2015;21(2):50-51. DOI:10.7196.SAJOG.858. Spontaneous rupture of the spleen – a rare and potentially fatal surgical emergency in the second trimester: Report of a case. M Heetun, MRCS; R Parameswaran, ...

  11. Recruitment of macrophages from the spleen contributes to myocardial fibrosis and hypertension induced by angiotensin II

    Directory of Open Access Journals (Sweden)

    Ning-Ping Wang

    2017-05-01

    Full Text Available Introduction: The purpose of this study was to determine whether macrophages migrated from the spleen are associated with angiotensin II-induced cardiac fibrosis and hypertension. Methods: Sprague-Dawley rats were subjected to angiotensin II infusion in vehicle (500 ng/kg/min for up to four weeks. In splenectomy, the spleen was removed before angiotensin II infusion. In the angiotensin II AT1 receptor blockade, telmisartan was administered by gastric gavage (10 mg/kg/day during angiotensin II infusion. The heart and aorta were isolated for Western blot analysis and immunohistochemistry. Results: Angiotensin II infusion caused a significant reduction in the number of monocytes in the spleen through the AT1 receptor-activated monocyte chemoattractant protein-1. Comparison of angiotensin II infusion, splenectomy and telmisartan comparatively reduced the recruitment of macrophages into the heart. Associated with this change, transforming growth factor β1 expression and myofibroblast proliferation were inhibited, and Smad2/3 and collagen I/III were downregulated. Furthermore, interstitial/perivascular fibrosis was attenuated. These modifications occurred in coincidence with reduced blood pressure. At week 4, invasion of macrophages and myofibroblasts in the thoracic aorta was attenuated and expression of endothelial nitric oxide synthase was upregulated, along with a reduction in aortic fibrosis. Conclusions: These results suggest that macrophages when recruited into the heart and aorta from the spleen potentially contribute to angiotensin II-induced cardiac fibrosis and hypertension.

  12. Body mass, spleen mass and level of thyroid hormones in juvenile hypothyroid rats

    Directory of Open Access Journals (Sweden)

    Roksandić Dragutin

    2006-01-01

    Full Text Available In this paper, the effect of hypothyroidism on body mass and spleen mass of rats was examined during the prenatal and early juvenile periods. Hypothyroidism was induced by the application of propylthiouracil (PTU in drinking water to the mothers from the first day of gravidity and during lactation, and the offspring were sacrificed on the 14th and 21st days after birth. The body mass of the juvenile rats was measured just before they were sacrificed. The concentrations of triiodothyronine (T3 and thyroxine (T4 in blood serum were determined in control and treated juvenile rats. The results indicate that PTU leads to a reduction in T3 and T4 serum concentrations in treated juvenile rats. Treated juvenile rats had a bigger body mass and spleen mass in comparison with control animals. These data indicate that hypothyroidism induced in the prenatal and early juvenile period leads to an increase in the body mass and spleen mass and disrupts the normal development of the spleen in the course of the examined period. .

  13. Lysosomal acid lipase deficiency in rats: Lipid analyses and lipase activities in liver and spleen

    International Nuclear Information System (INIS)

    Kuriyama, M.; Yoshida, H.; Suzuki, M.; Fujiyama, J.; Igata, A.

    1990-01-01

    We report the biological characterization of an animal model of a genetic lipid storage disease analogous to human Wolman's disease. Affected rats accumulated cholesteryl esters (13.3-fold), free cholesterol (2.8-fold), and triglycerides (5.4-fold) in the liver, as well as cholesteryl esters (2.5-fold) and free cholesterol (1.33-fold) in the spleen. Triglycerides did not accumulate, and the levels actually decreased in the spleen. Analysis of the fatty acid composition of the cholesteryl esters and triglycerides showed high percentages of linoleic acid (18:2) and arachidonic acid (20:4) in both organs, especially in the liver. No accumulation of phospholipids, neutral glycosphingolipids, or gangliosides was found in the affected rats. Acid lipase activity for [14C]triolein, [14C]cholesteryl oleate, and 4-methyl-umbelliferyl oleate was deficient in both the liver and spleen of affected rats. Lipase activity at neutral pH was normal in both liver and spleen. Heterozygous rats showed intermediate utilization of these substrates in both organs at levels between those for affected rats and those for normal controls, although they did not accumulate any lipids. These data suggest that these rats represent an animal counterpart of Wolman's disease in humans

  14. Spontaneous rupture of the spleen – a rare and potentially fatal ...

    African Journals Online (AJOL)

    Spontaneous (non-traumatic) rupture of the normal spleen in pregnancy is a rare clinical event that can endanger the lives of both mother and baby. The aetiology of the condition is unknown, but it occurs most commonly in multiple pregnancies and in the third trimester. We present a case of a spontaneous splenic rupture ...

  15. Coconut water solutions for the preservation of spleen, ovary, and skin autotransplants in rats.

    Science.gov (United States)

    Schettino César, J M; Petroianu, A; de Souza Vasconcelos, L; Cardoso, V N; das Graças Mota, L; Barbosa, A J A; Vianna Soares, C D; Lima de Oliveira, A

    2015-03-01

    The purpose of this study was to evaluate the efficacy of coconut water in the preservation of spleen, ovary, and skin autotransplantations in rats. Fifty female Wistar rats were divided randomly into 5 groups on the basis of the following tissue graft preservation solutions: group 1, lactated Ringer's; group 2, Belzer's solution; group 3, mature coconut water; group 4, green coconut water; and group 5, modified green coconut water. In group 5, the green coconut water solution was modified to obtain the same electrolyte composition as Belzer's solution. The spleen, ovaries, and a skin fragment were removed from each animal, stored for 6 hours in one of the solutions, and then re-implanted. The recoveries of tissue functions were assessed 90 days after surgery by means of spleen scintigraphy and blood tests. The implanted tissues were collected for histological analyses. Higher immunoglobulin G levels were observed in the animals of group 5 than in the animals of group 1. Differences in follicle-stimulating hormone levels were observed between groups 1 and 2 (P coconut water group (P coconut water allowed for the preservation of the spleen, ovaries, and skin for 6 hours, and the normal functions of these tissues were maintained in rats. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Robot-assisted spleen preserving pancreatic surgery in MEN1 patients

    NARCIS (Netherlands)

    Nell, Sjoerd; Brunaud, Laurent; Ayav, Ahmet; Bonsing, Bert A.; Groot Koerkamp, Bas; Nieveen van Dijkum, Els J.; Kazemier, Geert; de Kleine, Ruben H. J.; Hagendoorn, Jeroen; Molenaar, I. Quintus; Valk, Gerlof D.; Borel Rinkes, Inne H. M.; Vriens, Menno R.

    2016-01-01

    Multiple Endocrine Neoplasia type 1 (MEN1) patients often undergo multiple pancreatic operations at a young age. To describe robot-assisted and laparoscopic spleen-preserving pancreatic surgery in MEN1 patients, and to compare both techniques. Robot-assisted pancreatectomies of the DutchMEN1 study

  17. Robot-assisted spleen preserving pancreatic surgery in MEN1 patients

    NARCIS (Netherlands)

    Nell, Sjoerd; Brunaud, Laurent; Ayav, Ahmet; Bonsing, Bert A.; Groot Koerkamp, Bas; Nieveen van Dijkum, Els J.; Kazemier, Geert; de Kleine, Ruben H J; Hagendoorn, Jeroen; Molenaar, I. Quintus; Valk, Gerlof D.; Borel Rinkes, Inne H M; Vriens, Menno R.

    2016-01-01

    Background: Multiple Endocrine Neoplasia type 1 (MEN1) patients often undergo multiple pancreatic operations at a young age. Objective: To describe robot-assisted and laparoscopic spleen-preserving pancreatic surgery in MEN1 patients, and to compare both techniques. Methods: Robot-assisted

  18. Robot-assisted spleen preserving pancreatic surgery in MEN1 patients

    NARCIS (Netherlands)

    Nell, Sjoerd; Brunaud, Laurent; Ayav, Ahmet; Bonsing, Bert A.; Koerkamp, Bas Groot; van Dijkum, Els J. Nieveen; Kazemier, Geert; de Kleine, Ruben H. J.; Hagendoorn, Jeroen; Molenaar, I. Quintus; Valk, Gerlof D.; Rinkes, Inne H. M. Borel; Vriens, Menno R.

    2016-01-01

    BackgroundMultiple Endocrine Neoplasia type 1 (MEN1) patients often undergo multiple pancreatic operations at a young age. ObjectiveTo describe robot-assisted and laparoscopic spleen-preserving pancreatic surgery in MEN1 patients, and to compare both techniques. MethodsRobot-assisted

  19. Solitary metastasis of ampullary carcinoma to the spleen: a case report.

    Science.gov (United States)

    Phan, Tri M

    2018-04-01

    Here, we report a first case of ampullary cancer with solitary metastasis of the spleen, which was successfully treated with pancreatoduodenectomy and splenectomy and was discharged 7 days after the operation with outpatient chemotherapy. In such cases, physicians should consider splenectomy as an effective treatment option.

  20. Coexisting Sclerosing Angiomatoid Nodular Transformation of the Spleen with Multiple Calcifying Fibrous Pseudotumors in a Patient

    Directory of Open Access Journals (Sweden)

    Jen-Chieh Lee

    2007-01-01

    Full Text Available Primary tumor or tumor-like lesions of the spleen are rare. Among them, vascular lesions are the most common. Vascular tumor of the spleen is different from the usual hemangioma of soft tissue because the vascular structure of the spleen is unique. Sclerosing angiomatoid nodular transformation (SANT is a recently described vascular lesion of the spleen. Grossly, it is a multinodular, well-circumscribed tumor containing a hypervascular core. Microscopically, it comprises three types of vessels, and each type recapitulates the immunohistochemical characteristics of the normal vascular elements of the splenic red pulp, i.e. capillaries, sinusoids, and small veins, respectively. Because of the rarity of this entity, its actual pathogenesis is still unknown. In this study, we report a case of SANT occurring in a 43-year-old woman, in whom there were also multiple calcifying fibrous pseudotumors (CFPTs in the abdominal cavity. Both SANT and CFPT are thought to be variants of inflammatory pseudotumor. Coexistence of these two rare entities in a patient has never been reported, and this fact suggests that there might be a common mechanism contributing to the formation of these two types of lesions. [J Formos Med Assoc 2007;106(3:234-239