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31.
ETHNOPHARMACOLOGICAL RELEVANCE: Ginger rhizomes are used traditionally for management of different gastrointestinal disturbances. Several studies proved that the rhizome possesses diverse biological activities such as cytotoxic, antioxidant, and anti-inflammatory effects. Recently, interest in ginger for treatment of chronic inflammatory conditions has been renewed. AIM OF THE STUDY: The purpose of the present study is to evaluate the potential role of ginger extract [GE] in modulating the extent and severity of ulcerative colitis (UC), a chronically recurrent inflammatory bowel disease of unknown origin. MATERIALS AND METHODS: Male Wistar rats received 3 different doses of GE, sulfasalazine, or vehicle for 3 consecutive days before induction of UC by intra-rectal acetic acid administration, and continued further for 7 days after the induction. The colonic mucosal injury was assessed by macroscopic scoring, and histological examination. Furthermore, the mucosal content of malondialdehyde (MDA), protein carbonyl (PCO), and reduced glutathione (GSH) with the catalase (CAT) and superoxide dismutase (SOD) activity, were appraised as parameters of the redox state. Acute inflammatory response was determined by measuring myeloperoxidase (MPO), tumor necrosis factor (TNF-alpha), and prostaglandin E2 (PGE2). RESULTS: All parameters were altered in ulcerated rats, and improved in animals receiving GE, an effect that was comparable to that of the standard sulfasalazine, especially at the highest dose level. Colonic mucosal injury parallels with the histological and biochemical evaluations. CONCLUSIONS: Results showed a valuable effect of ginger extract against acetic acid-induced ulcerative colitis possibly by its antioxidant and anti-inflammatory properties. 相似文献
32.
OBJECTIVE
To assess the long‐term results in children with high‐grade renal trauma who were managed without surgery, as such treatment was initially successful but little is known about the late ipsilateral renal function and morphology.PATIENTS AND METHODS
The study included 13 children (nine boys and four girls; mean age 8 years, sd 5) with high‐grade renal injury who were managed without surgery between 1997 and 2001, and followed for a mean (sd , range) of 3 (2, 0.5–7) years. The trauma was caused by a motor‐car accident in five and falling from a height in eight children, and was on the right in 10 and on the left in three. There was gross and microscopic haematuria in 10 and three patients, respectively. The trauma was graded according to the American Association for Surgery of Trauma, with grades III, IV and V renal injury in six, four and three children, respectively. All patients were treated initially by observation; one required super‐selective embolization because of continuing haemorrhage. Three children with progressive urinary extravasation were treated with a percutaneous tube drain and JJ stent for 6 weeks. Patients were discharged after a mean (sd ) hospital stay of 9 (6) days. Ultrasonography then showed resolving haematoma in all patients with a mean (sd ) size of 7 (2) cm2. At the last follow‐up patients were re‐evaluated by a clinical examination, renal scintigraphy and computed tomography angiography.RESULTS
None of the children was hypertensive nor had any abnormality on urine analysis; all had normal serum creatinine levels, and scintigraphy and angiography showed normal contralateral kidneys in all. Ipsilateral abnormalities were detected in 12 patients, and included a single scar in five, multiple scars in six and a cystic lesion with multiple septa in one. There was no vascular complication or hydronephrosis, and no significant functional loss, with all affected kidneys having a split function of 41–50% at the last follow‐up.CONCLUSION
Although there is no late functional loss there are residual morphological changes in almost all children with high‐grade renal injury. This study provides objective support for the non‐operative management of high‐grade renal injury in children, but a prolonged follow‐up is warranted to assess the risk of progression of these abnormalities.33.
Faisal Hammad Mekky Koua Yasufumi Umena Keisuke Kawakami Jian-Ren Shen 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(10):3889-3894
Oxygen-evolving complex of photosystem II (PSII) is a tetra-manganese calcium penta-oxygenic cluster (Mn4CaO5) catalyzing light-induced water oxidation through several intermediate states (S-states) by a mechanism that is not fully understood. To elucidate the roles of Ca2+ in this cluster and the possible location of water substrates in this process, we crystallized Sr2+-substituted PSII from Thermosynechococcus vulcanus, analyzed its crystal structure at a resolution of 2.1 Å, and compared it with the 1.9 Å structure of native PSII. Our analysis showed that the position of Sr was moved toward the outside of the cubane structure of the Mn4CaO5-cluster relative to that of Ca2+, resulting in a general elongation of the bond distances between Sr and its surrounding atoms compared with the corresponding distances in the Ca-containing cluster. In particular, we identified an apparent elongation in the bond distance between Sr and one of the two terminal water ligands of Ca2+, W3, whereas that of the Sr-W4 distance was not much changed. This result may contribute to the decrease of oxygen evolution upon Sr2+-substitution, and suggests a weak binding and rather mobile nature of this particular water molecule (W3), which in turn implies the possible involvement of this water molecule as a substrate in the O-O bond formation. In addition, the PsbY subunit, which was absent in the 1.9 Å structure of native PSII, was found in the Sr-PSII structure. 相似文献
34.
H A Hammad M M el Fattah M Moris E H Madina A A el Abbasy A T Soliman 《Journal of tropical pediatrics》1990,36(3):126-127
Several different hepatic parenchymal lesions, including chronic hepatitis and cirrhosis, have been increasingly reported in children with schistosomal hepatic fibrosis (SHF) despite the known mesenchymal nature of the disease. The prevalence of persistent hepatitis (B) surface (HBs) antigenaemia and some hepatic functions have been determined in 52 children with SHF as well as in 100 age-matched healthy children. High prevalence of chronic HBs antigenaemia (58 per cent) has been demonstrated in children with SHF, but only in 2 per cent of the normal children. This denotes that children with SHF represent a dangerous reservoir for hepatitis B infection to the community. Serum alanine transferase (ALT) was higher than normal in 58 per cent of HBS seropositive patients and in none of the seronegative patients. This points to the risk of continual hepatic parenchymal injury to the HBs seropositive patients with schistosomiasis. 相似文献
35.
Inequalities in health: a comparative study between ethnic Norwegians and Pakistanis in Oslo, Norway
Hammad Raza Syed Odd Steffen Dalgard Akhtar Hussain Ingvild Dalen Bjorgulf Claussen Nora L Ahlberg 《International journal for equity in health》2006,5(1):7-9
Background
The objective of the study was to observe the inequality in health from the perspective of socio-economic factors in relation to ethnic Pakistanis and ethnic Norwegians in Oslo, Norway. 相似文献36.
37.
38.
A MEMS (micro-electro-mechanical systems) micropump with circular bossed membrane designed for nanoliter drug delivery is characterized in this article. A quasistatic model under consideration of low operating frequency is used to characterize this micropump. The mathematical model is an ordinary differential equation that describes the behavior of the micropump by including its key components of bossed membrane and inlet/outlet microvalves. Characterizations of bossed membrane and microvalves are carried out separately in the finite element analysis ANSYS package. The stroke volume of the membrane is calculated within the range that the linear deflection theory is valid. Analysis of the microvalve is a challenging task in microfluidics because it is a coupled field (solid-fluid coupling) problem. To solve the structural (solid) or fluid part separately is impractical in characterizing drug-delivery micropumps. Based on sequential weak solid-fluid coupling in ANSYS/FLOTRAN, the flow rates across the inlet and outlet microvalves are analyzed and simulated. Because the quasistatic equation contains several nonlinear terms, closed-form analytical solution for this equation is impossible; thus MATLAB is used to solve it numerically. The transient flow rate of the micropump is obtained by substituting the pressure in microchamber into the flow rate function of outlet microvalves. Integration of the function over 1 driving cycle and multiplication by the driving frequency provides the drug-delivery rate of the micropump. 相似文献
39.
Alloreactive T cell populations can show skewing of T-cell antigen receptor (TCR) Vbeta gene usage. The aims of the experiments were to compare in vivo and in vitro T cell alloresponses against donor alloantigens for TCR Vbeta gene usage. T-cell cultures from renal biopsies taken during acute rejection and pretransplant mixed lymphocyte cultures (MLC) were established from five renal transplant patients. TCR Vbeta gene usage, assessed with Vbeta family specific antibodies, showed that up to five different Vbeta families were significantly expanded. In four of five cases, there was close concordance between Vbeta families expanded from the biopsy and in MLC. T-cell clones from one renal biopsy were specific for the mismatched donor alloantigen and showed similar TCR Vbeta gene usage to the original T-cell line. The results show very similar patterns of TCR Vbeta gene usage in alloreactive T cells generated ex vivo or in vitro. 相似文献
40.
Erosions and urinary retention following polypropylene synthetic sling: Australasian survey 总被引:4,自引:0,他引:4
INTRODUCTION: There are few published reports on the incidence and management of urethral and vaginal erosions following the use of polypropylene synthetic slings. Moreover, there is very little Australasian data on their use for management of female urinary incontinence or on their associated complications. METHODS: A 1-page survey was mailed to the Australian and New Zealand members of the Urological Society of Australasia (N=326). The survey included questions on the use of polypropylene synthetic sling and the incidence and management of post-operative vaginal and urethral erosions and urinary retention. RESULTS: 198 surveys were returned (response rate: 61%). Polypropylene synthetic sling procedure is practiced by 39% of the respondents with a total of 1459 cases (TVT: 993, SPARC: 466). The incidence of vaginal erosions, urethral erosions and urinary retention was 1.2%, 0.6% and 6.5%, respectively. Thirty five percent of vaginal erosions were asymptomatic and only identified on routine post-operative vaginal examination. One third of urethral erosions presented more than 1 year after surgery and 89% of these were symptomatic. Thirty four percent of patients with urinary retention required surgical intervention to correct the retention. CONCLUSIONS: The incidence of urethral and vaginal erosions following polypropylene synthetic sling procedures is lower than that with other synthetic slings. However, a high index of suspicion and long-term follow-up are required to identify and manage these complications of this relatively new procedure. 相似文献