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We report a case of preputial myiasis in a child who presented with painful penile swelling suggestive of balanoposthitis. Treatment consisted of manual extraction of the worm followed by circumcision. Parasitologic study of the worm revealed a stage-three larva of Cordylobia anthropophaga. Through this case report and a review of the literature, we discuss the epidemiologic, diagnostic and therapeutic features of this disease.  相似文献   
113.

Objective

To evaluate the changes induced by retroperitoneal varicocelectomy on infertile men with nonobstructive azoospermia or severe oligozoospermia.

Patients and methods

The records were retrospectively evaluated for 46 infertile men with severe oligozoospermia (group I) and 15 infertile men with non-obstructive azoospermia (group II). The parameters of sperm before and after surgery and unassisted pregnancy rate were comparatively analysed.

Results

In the severe oligozoospermia group, the mean age of patients was 35.5 ± 6.4 (23–47 years). The mean duration of infertility was 4.9 ± 3.4 years (1–13 years). Of these patients, 41(89.1%) had bilateral varicocele and five (10.9%) had unilateral left-side varicocele. The varicocele was classified as grade I in two cases (4.3%), grade II in 39 cases (84.7%) and grade III in five cases (10.9%). After surgery, the mean sperm count increased from 1.85 ± 1.4 to 8.3 ± 10.3 millions/ml and mean sperm normal motility from 43.3 ± 21.5 to 47.6 ± 29.2%. The mean sperm abnormal morphology decreased from 65.05 ± 21.6 to 50.08 ± 26.9%. After a mean follow-up of 26.2 ± 11.6 months, the unassisted pregnancy rate in this group was 26.1%. In the non-obstructive azoospermia group (N = 15), the mean age of patients was 40.8 ± 7.2 (27–47 years). The mean duration of infertility was 6 ± 3.1 years (3–15 years). After varicocelectomy, an induction of spermatogenesis was observed in three patients (20%) with presence of motile sperm in the ejaculate. In this group, only one of the 15 men achieved unassisted pregnancy.

Conclusion

Retroperitoneal varicocele repair resulted in spermatogenesis induction with presence of motile ejaculated spermatozoa for some men with non-obstructive azoospermia. It induced spermatogenesis and fertility enhancement in men with severe oligozoospermia. Varicocele repair should be considered in men with non-obstructive azoospermia or severe oligozoospermia.  相似文献   
114.

Background  

Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens.  相似文献   
115.
Cyclophilins (Cyps), the intracellular receptors for Cyclosporine A (CsA), are responsible for peptidyl-prolyl cis-trans isomerisation and for chaperoning several membrane proteins. Those functions are inhibited upon CsA binding. Albeit its great benefits as immunosuppressant, the use of CsA has been limited by undesirable nephrotoxic effects, including sodium retention, hypertension, hyperkalemia, interstial fibrosis and progressive renal failure in transplant recipients. In this report, we focused on the identification of novel CypB-interacting proteins to understand the role of CypB in kidney function and, in turn, to gain further insight into the molecular mechanisms of CsA-induced toxicity. By means of yeast two-hybrid screens with human kidney cDNA, we discovered a novel interaction between CypB and the membrane Na/K-ATPase β1 subunit protein (Na/K-β1) that was confirmed by pull-down, co-immunoprecipitation and confocal microscopy, in proximal tubule-derived HK-2 cells. The Na/K-ATPase pump, a key plasma membrane transporter, is responsible for maintenance of electrical Na+ and K+ gradients across the membrane. We showed that CypB silencing produced similar effects on Na/K-ATPase activity than CsA treatment in HK-2 cells. It was also observed an enrichment of both alpha and beta subunits in the ER, what suggested a possible failure on the maturation and routing of the pump from this compartment towards the plasma membrane. These data indicate that CypB through its interaction with Na/K-β1 might regulate maturation and trafficking of the pump through the secretory pathway, offering new insights into the relationship between cyclophilins and the nephrotoxic effects of CsA.  相似文献   
116.
The spatial distribution of motile life stages of the two-spotted spider mite Tetranychus urticae Koch in Kenyan small-scale tomato fields was described by Taylor’s power law and an enumerative sampling plan was designed for research purposes. The exponential increase of T. urticae populations during three growing seasons permits the development and use of a simple exponential model for the design of a threshold-based chemical control system. For this purpose, a critical threshold of 440 motile mites per sample unit at the end of the growing season (12 weeks after transplanting) was translated into a proportion of 0.83 infested units in sample 3, i.e. five weeks after transplanting. A sequential binomial sampling plan with respect to the proportion of 0.83, five weeks after transplanting, was designed. The exponential model was extended to account for the influence of weather and host plant species. Model development and parameter estimation were based on three data sets (Kenyan tomato fields, Italian and Californian strawberry fields). The model satisfactorily predicted a positive influence on growth rates by (i) changing the host plant from tomato to strawberry, and (ii) temperature, while a negative effect resulted from (iii) rainfall; both (ii) and (iii) are controlled by temperature–rainfall interactions. In contrast, the estimated parameter values did not satisfactorily describe the expected responses at specific temperature and rainfall values. Nevertheless, the model allowed the rating of host plant species in the field. A fourth data set from Swiss apple orchards was used to test the model, and population build-up on the apple host plant appeared to be higher than on tomatoes but lower than on strawberry.  相似文献   
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119.
The study of a sea level fluctuation based on ostracods is carried out for the first time using core sediments of Mbawane and Retba Lakes, north coast of Senegal. A total of 26 species have been identified and most of them are encountered in the Gulf of Guinea shelf and its adjacent lagoons. The Retba Lake core, which is closer to the seashore, has yielded a richer and more diversified ostracod fauna composed of four assemblages. The F1 assemblage is composed of Cyprideis nigeriensis, Neomonoceratina iddoensis, and Aglaiocypris gambiensis, which characterises a slightly open lagoon developing under a humid climate with its edges covered with mangrove swamps. Assemblage F2, composed mainly of C. nigeriensis, N. iddoensis and “marine species”, which is richer and more diversified, points to a marine little gulf bordered by mangrove swamps. The F3 monospecific assemblage composed of C. nigeriensis indicates a drying confined lagoon under an arid climate. The F4 oligospecific association at the top, composed of C. nigeriensis and Pseudoconcha omatsolai, is typical of a slightly open saline lagoon under arid climate. Core sediments from Mbawane Lake have yielded scarce and badly preserved microfaunas which are distributed into three discontinuous levels that have been correlated to those of the Retba Lake core assemblages. The F1 assemblage composed of Leptocythere culpata and Xestoleberis sp. 2 corresponds to a slightly open lagoon covered at its bottom by marine macrophytes and algae. The F2 assemblage composed of N.iddoensis, Hemicytherura sp. A, Aglaiocypris gambiensis and Ruggieria tricostata characterises a more open lagoon bordered by mangrove swamps under a humid climate. The F3 assemblage is absent in the Mbawane Lake. The F4 monospecific association composed of C. nigeriensis characterises a drying lagoon under an arid climate. The overall marine influences were stronger in the Retba Lake while continental effects were dominant in Mbawane Lake during the same period. The two marine intrusions mentioned above may correspond to those of the Dakarian (3000 years B.P.) and the Saint-Louisian eras (2000–680 years B.P.) that existed during the Upper Holocene on the Senegalese coast.  相似文献   
120.
We investigated possible healing effects of melatonin (MEL) on biochemical and histological changes in the lungs of rat offspring caused by exposure to nicotine (NT) in utero. Pregnant rats were divided randomly into five groups. The SP group was treated with physiological saline. The EA group was treated with ethyl alcohol. The MEL group was treated with MEL. The NT group was treated with NT. The NT + MEL group was treated with NT and MEL. At the end of the study, the biochemistry and histopathology of lung tissue of the offspring were examined. Reduced alveolar development and increased numbers of alveolar macrophages and mast cells were observed in the NT group compared to the SP, EA and MEL groups. We also found increased malondialdehyde (MDA) levels and decreased total glutathione (GSH) levels in the NT group. Application of MEL ameliorated the histological and biochemical damage caused by NT. The number of alveoli was greater in the NT + MEL group than in the NT group. Also, the increased numbers of alveolar macrophages and mast cells resulting from exposure to NT were decreased following MEL treatment. We found that MEL caused a significant decrease in the level of MDA. Maternal exposure to NT caused significant structural and biochemical changes in the lungs of the offspring and administration of MEL ameliorated the changes.  相似文献   
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