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61.
Penile ectopic testis is a rare congenital abnormality. The aetiopathogenesis is still not well known.We report a case in a two-years-old child. The diagnosis was easy and required no exploration. The orchidopexy in dartos after lowering the testis was easy due to the sufficient length of the spermatic cord. Three years later, the lowered testis appeared normal. We review the other forms of penile ectopic testis reported in the literature and those requiring further exploration. 相似文献
62.
A haplotype map of allohexaploid wheat reveals distinct patterns of selection on homoeologous genomes 总被引:1,自引:0,他引:1
Katherine W Jordan Shichen Wang Yanni Lun Laura-Jayne Gardiner Ron MacLachlan Pierre Hucl Krysta Wiebe Debbie Wong Kerrie L Forrest IWGS Consortium Andrew G Sharpe Christine HD Sidebottom Neil Hall Christopher Toomajian Timothy Close Jorge Dubcovsky Alina Akhunova Luther Talbert Urmil K Bansal Harbans S Bariana Matthew J Hayden Curtis Pozniak Jeffrey A Jeddeloh Anthony Hall Eduard Akhunov 《Genome biology》2015,16(1)
BackgroundBread wheat is an allopolyploid species with a large, highly repetitive genome. To investigate the impact of selection on variants distributed among homoeologous wheat genomes and to build a foundation for understanding genotype-phenotype relationships, we performed population-scale re-sequencing of a diverse panel of wheat lines.ResultsA sample of 62 diverse lines was re-sequenced using the whole exome capture and genotyping-by-sequencing approaches. We describe the allele frequency, functional significance, and chromosomal distribution of 1.57 million single nucleotide polymorphisms and 161,719 small indels. Our results suggest that duplicated homoeologous genes are under purifying selection. We find contrasting patterns of variation and inter-variant associations among wheat genomes; this, in addition to demographic factors, could be explained by differences in the effect of directional selection on duplicated homoeologs. Only a small fraction of the homoeologous regions harboring selected variants overlapped among the wheat genomes in any given wheat line. These selected regions are enriched for loci associated with agronomic traits detected in genome-wide association studies.ConclusionsEvidence suggests that directional selection in allopolyploids rarely acted on multiple parallel advantageous mutations across homoeologous regions, likely indicating that a fitness benefit could be obtained by a mutation at any one of the homoeologs. Additional advantageous variants in other homoelogs probably either contributed little benefit, or were unavailable in populations subjected to directional selection. We hypothesize that allopolyploidy may have increased the likelihood of beneficial allele recovery by broadening the set of possible selection targets.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-015-0606-4) contains supplementary material, which is available to authorized users. 相似文献63.
Ahmadou H. Dicko Lassane Percoma Adama Sow Yahaya Adam Charles Mahama Issa Sidibé Guiguigbaza-Kossigan Dayo Sophie Thévenon William Fonta Safietou Sanfo Aligui Djiteye Ernest Salou Vincent Djohan Giuliano Cecchi Jérémy Bouyer 《PLoS neglected tropical diseases》2015,9(7)
Background
African animal trypanosomosis (AAT) is a major constraint to sustainable development of cattle farming in sub-Saharan Africa. The habitat of the tsetse fly vector is increasingly fragmented owing to demographic pressure and shifts in climate, which leads to heterogeneous risk of cyclical transmission both in space and time. In Burkina Faso and Ghana, the most important vectors are riverine species, namely Glossina palpalis gambiensis and G. tachinoides, which are more resilient to human-induced changes than the savannah and forest species. Although many authors studied the distribution of AAT risk both in space and time, spatio-temporal models allowing predictions of it are lacking.Methodology/Principal Findings
We used datasets generated by various projects, including two baseline surveys conducted in Burkina Faso and Ghana within PATTEC (Pan African Tsetse and Trypanosomosis Eradication Campaign) national initiatives. We computed the entomological inoculation rate (EIR) or tsetse challenge using a range of environmental data. The tsetse apparent density and their infection rate were separately estimated and subsequently combined to derive the EIR using a “one layer-one model” approach. The estimated EIR was then projected into suitable habitat. This risk index was finally validated against data on bovine trypanosomosis. It allowed a good prediction of the parasitological status (r2 = 67%), showed a positive correlation but less predictive power with serological status (r2 = 22%) aggregated at the village level but was not related to the illness status (r2 = 2%).Conclusions/Significance
The presented spatio-temporal model provides a fine-scale picture of the dynamics of AAT risk in sub-humid areas of West Africa. The estimated EIR was high in the proximity of rivers during the dry season and more widespread during the rainy season. The present analysis is a first step in a broader framework for an efficient risk management of climate-sensitive vector-borne diseases. 相似文献64.
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
65.
B. Fall B. Diao Y. Sow A. Sarr P.A. Fall A.K. Ndoye M. Ba B.A. Diagne 《Andrologie》2010,20(4):257-261
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66.
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
67.
Bodo Brand Anja Hartmann Dirk Repsilber Bettina Griesbeck-Zilch Olga Wellnitz Christa Kühn Siriluck Ponsuksili Heinrich HD Meyer Manfred Schwerin 《遗传、选种与进化》2011,43(1):24
Background
During the past ten years many quantitative trait loci (QTL) affecting mastitis incidence and mastitis related traits like somatic cell score (SCS) were identified in cattle. However, little is known about the molecular architecture of QTL affecting mastitis susceptibility and the underlying physiological mechanisms and genes causing mastitis susceptibility. Here, a genome-wide expression analysis was conducted to analyze molecular mechanisms of mastitis susceptibility that are affected by a specific QTL for SCS on Bos taurus autosome 18 (BTA18). Thereby, some first insights were sought into the genetically determined mechanisms of mammary gland epithelial cells influencing the course of infection.Methods
Primary bovine mammary gland epithelial cells (pbMEC) were sampled from the udder parenchyma of cows selected for high and low mastitis susceptibility by applying a marker-assisted selection strategy considering QTL and molecular marker information of a confirmed QTL for SCS in the telomeric region of BTA18. The cells were cultured and subsequently inoculated with heat-inactivated mastitis pathogens Escherichia coli and Staphylococcus aureus, respectively. After 1, 6 and 24 h, the cells were harvested and analyzed using the microarray expression chip technology to identify differences in mRNA expression profiles attributed to genetic predisposition, inoculation and cell culture.Results
Comparative analysis of co-expression profiles clearly showed a faster and stronger response after pathogen challenge in pbMEC from less susceptible animals that inherited the favorable QTL allele ''Q'' than in pbMEC from more susceptible animals that inherited the unfavorable QTL allele ''q''. Furthermore, the results highlighted RELB as a functional and positional candidate gene and related non-canonical Nf-kappaB signaling as a functional mechanism affected by the QTL. However, in both groups, inoculation resulted in up-regulation of genes associated with the Ingenuity pathways ''dendritic cell maturation'' and ''acute phase response signaling'', whereas cell culture affected biological processes involved in ''cellular development''.Conclusions
The results indicate that the complex expression profiling of pathogen challenged pbMEC sampled from cows inheriting alternative QTL alleles is suitable to study genetically determined molecular mechanisms of mastitis susceptibility in mammary epithelial cells in vitro and to highlight the most likely functional pathways and candidate genes underlying the QTL effect. 相似文献68.
Arame Ndiaye Karmadine Hima Gauthier Dobigny Aliou Sow Ambroise Dalecky Khalilou Bâ Massamba Thiam Laurent Granjon 《Zoologischer Anzeiger》2014
Aridification processes that affected the Sahelian area of West Africa during the last decades have induced significant changes in plant and animal communities of this region. In rodents, the genus Gerbillus characteristic of North African and Asian arid habitats has been affected by this climatic and environmental trends. Several species of this genus showed a southward range expansion in recent years into the Sahelian bioclimatic zone. Recent sampling in several localities of West Africa (Mali, Niger and Senegal) enabled us to collect numerous specimens of small gerbils. An integrative study of these samples using molecular, morphological and cytogenetical methods revealed that many of them were attributable to Gerbillus nancillus, a secretive and poorly known species. Gerbillus nancillus appears characterized by a well differentiated karyotype with 2n = 56 chromosomes, and to represent a unique genetic lineage within this genus. Body and skull measurements of G. nancillus were compared with those of the morphologically similar Gerbillus henleyi, which provided diagnostic clues between them. These new data significantly expand the distribution area of G. nancillus, which now ranges from Sudan in the East to Senegal in the West. G. nancillus is here reported from numerous new localities in Niger and Mali, and for the first time in Senegal, which raises questions about the origin of its presence and the colonization routes it followed to get there. We also show that G. henleyi and G. nancillus are sympatric and apparently often syntopic in the sub-Saharan part of the distribution of G. henleyi. 相似文献
69.
S. L. S. Sow G. Khoo L. K. Chong T. J. Smith P. L. Harrison H. K. A. Ong 《World journal of microbiology & biotechnology》2014,30(2):757-766
Disused tin-mining ponds make up a significant amount of water bodies in Malaysia particularly at the Kinta Valley in the state of Perak where tin-mining activities were the most extensive, and these abundantly available water sources are widely used in the field of aquaculture and agriculture. However, the natural ecology and physicochemical conditions of these ponds, many of which have been altered due to secondary post-mining activities, remains to be explored. As ammonia-oxidizing bacteria (AOB) are directly related to the nutrient cycles of aquatic environments and are useful bioindicators of environmental variations, the focus of this study was to identify AOBs associated with disused tin-mining ponds that have a history of different secondary activities in comparison to ponds which were left untouched and remained as part of the landscape. The 16S rDNA gene was used to detect AOBs in the sediment and water sampled from the three types of disused mining ponds, namely ponds without secondary activity, ponds that were used for lotus cultivation and post-aquaculture ponds. When the varying pond types were compared with the sequence and phylogenetic analysis of the AOB clone libraries, both Nitrosomonas and Nitrosospira-like AOB were detected though Nitrosospira spp. was seen to be the most ubiquitous AOB as it was present in all ponds types. However, AOBs were not detected in the sediments of idle ponds. Based on rarefaction analysis and diversity indices, the disused mining pond with lotus culture indicated the highest richness of AOBs. Canonical correspondence analysis indicated that among the physicochemical properties of the pond sites, TAN and nitrite were shown to be the main factors that influenced the community structure of AOBs in these disused tin-mining ponds. 相似文献