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41.
42.
Sertoli cells are important for maintenance of the immune privileged environment of the testis and prolong survival of cotransplanted cells. The objective of the current study was to examine the immunoprotective properties of a mouse Sertoli cell line (MSC-1) in order to identify a Sertoli cell line that could be used to aid in investigation of the immunoprotective abilities of Sertoli cells. BALB/c islets were cotransplanted with 0-9 million primary BALB/c Sertoli cells or MSC-1 cells into diabetic C3H or BALB/c mice and protection of grafted islets was examined by monitoring blood glucose levels and immunohistochemical analysis. Additionally, expression of potential immunoprotective factors in MSC-1 cells was examined. Cotransplantation of islets with 3 million primary Sertoli cells significantly prolonged islet allograft survival (61.1 +/- 6.9 days; p < 0.05) compared with control mice that received allogeneic islets alone (26.9 +/- 2.1 days). Grafts collected from normoglycemic C3H mice at 100 days posttransplant contained insulin-positive beta-cells adjacent to allogeneic Sertoli cells arranged in tubule-like structures. In contrast, cotransplantation of islet allografts with MSC-1 cells did not prolong islet survival (average 29.8 +/- 3.3 days) regardless of the number of MSC-1 cells transplanted and the rejected grafts contained very few beta-cells and randomly arranged MSC-1 cells. The lack of islet cell survival was not due to detrimental effects of MSC-1 cells because syngneic islets cotransplanted with MSC-1 cells were functional throughout the study. MSC-1 cells were found to express known Sertoli cell-expressed, immunoprotective factors, clusterin, Fas ligand, and transforming growth factor-beta1, suggesting additional factors may be involved in Sertoli cell immune privilege. These data indicate the MSC-1 cell line lacks the immunoprotective properties associated with primary Sertoli cells. Further study of this cell line could be useful in examining the mechanisms that enable Sertoli cells to provide immune privilege. 相似文献
43.
Piyush Patel George Philip William Yang Robert Call Friedrich Horak Craig LaForce Leen Gilles Graigory C Garrett S Balachandra Dass Barbara A Knorr Theodore F Reiss 《Annals of allergy, asthma & immunology》2005,95(6):551-557
BACKGROUND: Perennial allergic rhinitis (PAR) is a persistent allergic inflammation of the upper respiratory tract due to year-round allergen exposure. OBJECTIVE: To evaluate the leukotriene receptor antagonist montelukast for the treatment of PAR. METHODS: Protocol 265 was a 2-arm study performed during the winter. After a placebo run-in period, adults with perennial allergen sensitivity and active symptoms of PAR were randomized to receive 10 mg of montelukast (n=1002) or placebo (n=990) once daily during a 6-week, double-blind, active-treatment period. The primary end point was the daytime nasal symptoms score, defined as the average of scores for nasal congestion, rhinorrhea, and sneezing rated daily by patients. RESULTS: Statistically significant improvements in PAR symptoms were seen in patients treated with montelukast. Their daytime nasal symptoms scores were reduced during treatment compared with those of the placebo group: the difference between treatments in least squares mean change from baseline was -0.08 (95% confidence interval [CI], -0.12 to -0.04; P < .001). Montelukast treatment also improved global evaluations of allergic rhinitis by patients and Rhinoconjunctivitis Quality of Life Questionnaire scores: differences vs the placebo group were -0.15 (95% CI, -0.27 to -0.04; P < .01) and -0.15 (95% CI, -0.24 to -0.06; P < .001), respectively. Other end points that showed statistically significant improvement with montelukast treatment were nighttime symptoms and each of the 4 nasal symptoms (congestion, rhinorrhea, sneezing, and itching). The treatment effects of montelukast were stable and persistent during the entire 6 weeks of treatment. CONCLUSION: Montelukast provided statistically significant relief of PAR symptoms during 6 weeks of treatment. 相似文献
44.
Using histochemical techniques γ-glutamyl transpeptidase activity has been localized mainly in the cuticle-hypodermis in Ascaris suum. The specific activity of γ-glutamyl transpeptidase was 3.87 ± 0.49 μmol h−1 (g tissue)−1 in cuticle-hypodermis as compared to gastrointestinal tract, where it was 0.07 ± 0.02 μmol h−1 (g tissue)−1, and muscle and reproductive tract where it was <0.001 μmol h−1 (g tissue)−1. When cuticle sections were incubated with labelled glutamine a large portion of the glutamine nitrogen was recovered as ammonia which indicated glutamine uptake and utilization by the cuticle-hypodermis. Collectively these histochemical and biochemical data support the fact that γ-glutamyl transpeptidase activity is found in the cuticle-hypodermis of A. suum and this may be an indication that amino acid absorption could occur through the cuticle via the γ-glutamyl cycle. 相似文献
45.
46.
Efforts in treatment have concentrated on the development of an ideal carrier for effective delivery of therapeutic agents into affected regions of a human body. Ideally, drugs would have to be delivered as close as possible, if not within, the affected cell. From its seminal production 30 years ago for the purpose of membrane research, the liposome has passed through various stages of development to become a vehicle of choice for numerous therapeutic applications. One category of these vesicles, positively charged or cationic liposomes, are commonly used for transfer of reporter and therapeutic genes into both mammalian and nonmammalian cells both in vitro and in vivo. While cationic liposomes have many advantages over other forms of delivery mechanisms, several problems hinder their efficient use. Development of a better liposomal transfection agent may indeed require a closer look at the present cationic vesicles, the biological milieu to which they are exposed, mechanisms of membrane breaching, and limitations to entry into the nucleus. This review discusses these limitations and suggests potential ways of improving liposomal delivery of genes in the context of solid tumors. 相似文献
47.
George Philip Cesar Villarán David S Pearlman Tom Loeys S Balachandra Dass Theodore F Reiss 《The Journal of asthma》2007,44(3):213-217
The objective of this double-blind cross-over study was to evaluate montelukast for the prevention of exercise-induced bronchoconstriction (EIB). Sixty-two patients with EIB (post-exercise decrease in forced expiratory volume in 1 second (FEV1) ≥ 20% at pre-randomization) were randomized to montelukast 10 mg or placebo, followed by exercise-challenge 2, 12, and 24 hours postdose. The primary endpoint was the maximum percent-fall in FEV1 (from pre-exercise FEV1) during 60 minutes after exercise-challenge at 2 hours postdose. This endpoint was improved after montelukast (mean ± SD = 11.7% ± 10.8) versus placebo (17.5% ± 13.8) (p ≤ 0.001); numerically greater improvements were seen at 12 hours and 24 hours. A quicker time to recovery after challenge (p ≤ 0.001) and a smaller area under the curve for percent-fall in FEV1 during 60 minutes after challenge (p ≤ 0.01) were seen with montelukast at 2 hours. At this timepoint, more patients taking montelukast (45/54) than taking placebo (37/54) were protected against EIB (p = 0.039). We concluded that montelukast provided significant protection against EIB at 2 hours after a single dose. 相似文献
48.
Rupinder Kaur Pooja Rani Divye Malhotra Rajwant Kaur Praveen Kumar Dass 《Oral and maxillofacial surgery》2016,20(3):331-336
Background
Reports of post herpetic maxillofacial complications have been very rarely documented in the literature that includes periapical lesions, calcified and devitalized pulps, resorption of roots, osteonecrosis, and spontaneous exfoliation of teeth. The atypical feature of the case of concern to the dental surgeon is the rare complication of spontaneous tooth exfoliation following herpes zoster.Case report
This case reports a male patient of age 47 years who reported to the Department of Periodontology with the chief complaint of mobility in the left upper central incisor. Patient history revealed herpes zoster infection that began 11 days earlier along with underlying diabetes mellitus condition. We hereby report a known diabetic patient with history of herpes zoster infection who presented with rare complication of spontaneous tooth exfoliation involving the maxillary division of the trigeminal nerve.Discussion
Limited number of cases has been reported in the literature regarding spontaneous teeth exfoliation secondary to herpes zoster. The exact pathogenesis regarding the spontaneous exfoliation of teeth in herpes zoster patient is still controversial. Thus, an oral health care provider should be aware of this rare complication while managing a case of tooth mobility with the previous history of herpes zoster of trigeminal nerve.49.
A prospective randomized trial of 130 patients was carried out to compare simple ligature with invagination of the appendix stump. There were 64 and 66 patients, respectively, in the two groups and they were well matched for age, sex, weight and severity of appendicitis. One patient in the invagination group developed wound infection but there was no infection in the other group. This difference was not statistically significant (P greater than 0.5) and there was no evidence of adhesive ileus in either group after a mean follow-up period of nine months. We recommend simple ligature of the appendix stump as a safe procedure. 相似文献
50.
Growth hormone secretagogue receptors in rat and human gastrointestinal tract and the effects of ghrelin 总被引:10,自引:0,他引:10
Dass NB Munonyara M Bassil AK Hervieu GJ Osbourne S Corcoran S Morgan M Sanger GJ 《Neuroscience》2003,120(2):443-453
The peptide hormone ghrelin is known to be present within stomach and, to a lesser extent, elsewhere in gut. Although reports suggest that gastric function may be modulated by ghrelin acting via the vagus nerve, the gastrointestinal distribution and functions of its receptor, the growth hormone secretagogue receptor (GHS-R), are not clear and may show signs of species-dependency. This study sought to determine the cellular localisation and distribution of GHS-R-immunoreactivity (-Ir) using immunofluorescent histochemistry and explore the function of ghrelin in both human and rat isolated gastric and/or colonic circular muscle preparations in which nerve-mediated responses were evoked by electrical field stimulation. The expression of GHS-R-Ir differed to a greater extent between species than between gut regions of the same species. Both the human and rat gastric and colonic preparations (n=3 each) expressed GHS-R-Ir within neuronal cell bodies and fibres, cells associated with gastric glands and putative entero-endocrine and/or mast cells. Smooth muscle cells and epithelia were devoid of GHS-R-Ir and only rat preparations expressed GHS-R-Ir on nerve fibres associated with the muscle layers. GHS-R-Ir was fully competed in all cases in pre-adsorption studies and antiserum specificity was confirmed using a cell line transiently expressing the rat GHS-R. In rat isolated forestomach circular muscle, ghrelin 0.1-10 microM had no effect on smooth muscle tension but concentration-dependently facilitated the amplitude of contractions evoked by excitatory nerve stimulation (n=4-7; P<0.05 for each concentration versus vehicle; n=18). When examined under similar conditions, in both rat distal colon (n=4-6, P>0.05 each) and human ascending (n=3) and sigmoid (n=1) colon, these concentrations of ghrelin were without effect (P>0.05 each). The data suggest that ghrelin has the potential to profoundly affect gastrointestinal functions in both species and at least one of these functions is to exert a gastric prokinetic activity. Moreover, we suggest that this activity of ghrelin is mediated via the enteric nervous system, in addition to known vagus nerve-dependent mechanisms. 相似文献