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101.
The role of endoscopic ultrasound (EUS) in the diagnosis of biliary strictures is well established, and emerging evidence suggests it may also play a therapeutic role. Differentiating between benign and malignant causes of biliary strictures can be challenging, but EUS can aid in their diagnosis and may predict resectability. The diagnostic yield of EUS combined with fine-needle aspiration (FNA) is excellent, especially in distal bile duct strictures, and far surpasses endoscopic retrograde cholangiopancreatography (ERCP) with brushings. Intraductal ultrasound may add to the diagnostic sensitivity of ERCP with brushings when no mass is seen on cross-sectional imaging or EUS, or when EUS with FNA is negative and suspicion of cancer persists. EUS-guided cholangiography is an emerging technique that may aid biliary decompression when ERCP has failed or is not possible; however, new therapeutic echoendoscopes or accessories are needed before the use of this technique can become more widespread.  相似文献   
102.
Mishra A  Hogan SP  Brandt EB  Rothenberg ME 《Blood》2000,96(4):1538-1544
The gastrointestinal immune system is traditionally thought to be composed of lymphocytes located within Peyer's patches and the lamina propria. We have recently reported that eosinophils also reside in the gastrointestinal tract during healthy states, in particular, within the lamina propria, and that these cells substantially increase after oral allergen exposure. We now demonstrate the presence of eosinophils in Peyer's patches and characterize the signals that regulate the accumulation of eosinophils in Peyer's patches. In contrast to the lamina propria, intestinal Peyer's patches have very low levels of eosinophils under healthy states. However, elevated levels of interleukin-5 (IL-5), generated by transgenic or pharmacologic approaches, result in a dramatic increase in eosinophil levels in Peyer's patches. Most eosinophils are located in the outer cortex and interfollicular regions of the Peyer's patches. To dissect the mechanism of eosinophil trafficking to Peyer's patches, the role of eotaxin was examined. Mice transgenic for IL-5 and genetically deficient in eotaxin were found to have reduced levels of eosinophils in Peyer's patches compared with IL-5-transgenic mice. To prove that eosinophils also traffic to Peyer's patches in wild-type mice, allergic hypersensitivity was induced and Peyer's patches were examined. Exposure to mucosal allergen promoted marked accumulation of eosinophils in Peyer's patches and this process was attenuated in eotaxin-deficient mice. In summary, these data demonstrate that elevated levels of IL-5 and mucosal allergen exposure promote eotaxin-dependent eosinophil trafficking to Peyer's patches. These studies suggest that eosinophils may cooperate with lymphocytes in the development of mucosal immune responses in the gastrointestinal tract. (Blood. 2000;96:1538-1544)  相似文献   
103.

Background

Extended phenotyping is one of the important method of reducing red cell alloimmunisation. Extended phenotyping of red cells from voluntary donors have many uses in addition to its application in population genetics. As there was very little data extended phenotyping on a cohort of Indian Voluntary blood donors this project was undertaken.

Study design & methodology

200 regular voluntary blood donors having ‘O’ blood group were included for red cell antigen typing of Rh (D,C,E,c,e), Kell (K, k, Kpa, Kpb), Duffy (Fya, Fyb), Kidd (Jka, Jkb), Lewis(Lea, Leb), P(P1), MNS (M, N,S,s), and Lutheran (Lua, Lub), Colton (Coa, Cob), Diago (Diaa, Wra), Vw and Xga antigens using conventional antisera provided by DIAGAST. Calculations of antigen and phenotypes frequencies were expressed as percentages.

Results

Out of 200 ‘O’ group blood donors, 96.5% were Rh D and 2.5% were K positive. Amongst Rh antigens, e was the most common (100%) followed by D, C (91.0%), c (50.5%) and E (16.5%) with DCe/DCe (R1R1, 48.0%) being the most common phenotype. In Kell blood group system, we found k antigen to be 100% and a rare phenotype Kp (a?+?b+) was found in 1% of the donors. For Kidd and Duffy blood group systems, Jk (a?+?b+) and Fy (a?+?b-) were the most common phenotypes (39.0% and 64.0%, respectively). In the MNS blood group system, M?+?N+ (67.5%) and S?+?s+(43.5%) were the most common phenotypes. There were antigens like Cw(3.5%), K(2.3%), Kpa(1.2%), Ina(1.0%), Vw(1.2%), Coa(4.5%), Cob(1%), Lua(1.75%), Dia+(1.2%), and Wra+(0.6%) with frequency < 5% in the donor population.

Conclusion

Extensively antigen phenotypes group ‘O’ red cells showed significant variation with other population from India as well as with Caucasian and black population. Extensive phenotyping ‘O’ group regular blood donors of red cell antigens is very useful to prepare in-house red cell panels for identification of alloantibodies.  相似文献   
104.
105.
Schwannomas are benign, encapsulated, primary neurilemmal tumors composed of proliferating Schwann cells. Schwannomas are commonly seen in the orbit, but are rare on the epibulbar surface. Herein, we report a case of a 12-year-old boy who presented to us with a slow-growing painless subconjunctival mass in the left eye. There was no intraocular extension of the mass and intra-operatively, the mass could be clearly delineated and was excised off the underlying sclera. Histopathological examination of the mass showed typical features of schwannoma and immunohistochemistry helped to confirm the diagnosis. There was no recurrence of the lesion observed at follow-up 26 months after surgery. Here, we describe this uncommon tumor and review the available literature. Although rare, an epibulbar schwannoma should be considered in the differential diagnosis of an amelanotic, painless subconjunctival nodular mass. Excision of the lesion is the recommended treatment.  相似文献   
106.
107.

Aim:

Black grape peel possesses a substantial amount of polyphenolic antimicrobial compounds that can be used for controlling the growth of pathogenic microorganisms. The purpose of this study was to assess antibacterial and antifungal activity of black grape peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds, respectively.

Materials and Methods:

Peel of grape was subjected to polyphenolic extraction using different solvents viz., water, ethanol, acetone, and methanol. Antibiotic-resistant strains of Staphylococcus aureus, Enterococcus faecalis, Enterobacter aerogenes, Salmonella typhimurium, and Escherichia coli were screened for the antibacterial activity of different grape extracts. Antibacterial activity was analyzed using agar well diffusion method. Penicillium chrysogenum, Penicillium expansum, Aspergillus niger and Aspergillus versicolor were screened for the antifungal activity. Antifungal activity was determined by counting nongerminated spores in the presence of peel extracts.

Results:

As compared to other solvent extracts, methanol extracts possessed high antibacterial and antifungal activity. S. typhimurium and E. coli showed complete resistance against antibacterial action at screened concentrations of grape peel extracts. Maximum zone of inhibition was found in case of S. aureus, i.e., 22 mm followed by E. faecalis and E. aerogenes, i.e., 18 and 21 mm, respectively, at 1080 mg tannic acid equivalent (TAE)/ml. The maximum and minimum percent of growth inhibition was shown by P. expansum and A. niger as 73% and 15% at 1080 TAE/ml concentration of grape peel extract, respectively.

Conclusions:

Except S. typhimurium and E. coli, growth of all bacterial and mold species were found to be significantly (P < 0.05) inhibited by all the solvent extracts.KEY WORDS: Antibacterial activity, antifungal activity, polyphenolic compounds, Vitis vinifera L, zone of inhibition  相似文献   
108.
In the present investigation we have prepared and characterized curcumin (CN)-containing chitosan nanoparticles (CS-NPs) coated with Eudragit FS 30D for colon-specific drug delivery for treatment of ulcerative colitis. Methods: CS-NPs were prepared by ionic gelation using tripolyphosphate. To specify pH sensitive delivery, CS–CN-NPs were coated with Eudragit FS 30D by using a solvent evaporation method. Different process parameters were evaluated, and the optimized formulation was characterized by particle size, size distribution, zeta potential and encapsulation efficiency before lyophilization. The lyophilized product was further subjected to Fourier-transform infrared spectroscopy, and particle morphology and in vitro drug release in different media were studied. Results: the kinetics of in vitro drug release from the CS–CN-NPs revealed sustained release behaviour of the developed carriers. In vivo biodistribution study by gamma-scintigraphy showed good accumulation of the developed nanocarriers in the colonic region. Conclusion: sustained and pH stimulated delivery of CN to the colon was successfully attained via coating of CS-NPs with Eudragit FS 30D to circumvent poor absorption and availability of CN.

In the present investigation we have prepared and characterized curcumin (CN)-containing chitosan nanoparticles (CS-NPs) coated with Eudragit FS 30D for colon-specific drug delivery for treatment of ulcerative colitis.  相似文献   
109.
Heroin use and addiction pose serious risks and side effects due to overdose. Quantification of heroin in biological samples is challenging due to rapid deacetylation of heroin to its active metabolites. In this study, we report the quantification of metabolic degradation of heroin by-products in biological urine samples. The presence of the drug was monitored after oral administration of heroin at different time intervals. Various biophysical techniques, such as high performance liquid chromatography (HPLC) and mass spectrometry (MS) were used to evaluate the presence of the drug. A competitive fluorescence based immunoassay was developed with a limit of detection (LOD) up to 0.01 ng mL−1 and the IC50 value was 0.1 ng mL−1, while the dipstick assay shows a LOD up to 5 ng mL−1. Rapid detection of narcotic drugs was carried out for biological urine samples collected at various time points. Validation of the developed dipstick was carried out for the standard as well as the spiked urine samples by fluorescence based immunoassay (FIA), using anti-morphine antibodies. A strong correlation (R = 0.94) was obtained between the developed dipstick and FIA assay for biological urine samples collected at various time points. The developed immunochromatographic dipstick is highly sensitive, field applicable and cost effective, and can serve as a first choice for the monitoring of narcotic drugs in blood, urine and saliva in drug addicts and athletes.

Pathway of heroin degradation post oral administration in mice.  相似文献   
110.
Autoimmune hemolytic anaemia (AIHA) has traditionally been classified based on the temperature sensitivity of the autoagglutinins as warm (WAIHA), cold (CAIHA) and mixed type. Autoagglutinin may be of IgG or IgM type. The present prospective study was conducted to evaluate the profile of clinical picture, severity of haemolysis, treatment response of steroid. This study on patients of adult primary AIHA was conducted by taking complete history followed by detail physical examination. Laboratory investigations were performed to establish haemolytic anaemia and to assess severity of haemolysis. Immunehematological work up including blood grouping, direct antiglobulin test (DAT), IAT, antibody screening, adsorption elution was performed to diagnose type of AIHA. All cases were followed up to assess the response to prednisolone. All the data were collected and analysed by SPSS 19. Out of 62 primary AIHA cases, female were affected more than male (41:21). WAIHA is most common type (42, 67.8%) followed by mixed (20.9%) and cold AIHA (11.3%). Severity of haemolysis showed significant correlation with the DAT strength and not with type of AIHA. (P < 0.05) On oral prednisolone, 22 cases attended complete remission, while relapse, drug dependency and partial remission was achieved in 13, 9, 3 cases respectively. Severity of haemolysis in AIHA is directly related with DAT strength. WAIHA is most common type and can be managed with oral prednisolone (cr 45.2%), without red cell transfusion in most of cases. Mixed type AIHA cases were presented mostly with severe haemolysis, with minimum therapeutic response to prednisolone and maximum relapse/drug dependency.  相似文献   
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