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41.
The Horn of Africa forms one of the two main historical entry points of domestics into the continent and Ethiopia is particularly important in this regard. Through the analysis of mitochondrial DNA (mtDNA) d‐loop region in 309 individuals from 13 populations, we reveal the maternal genetic variation and demographic dynamics of Ethiopian indigenous goats. A total of 174 variable sites that generated 231 haplotypes were observed. They defined two haplogroups that were present in all the 13 study populations. Reference haplotypes from the six globally defined goat mtDNA haplogroups show the two haplogroups present in Ethiopia to be A and G, the former being the most predominant. Although both haplogroups are characterized by an increase in effective population sizes (Ne) predating domestication, they also have experienced a decline in Ne at different time periods, suggesting different demographic histories. We observed seven haplotypes, six were directly linked to the central haplotypes of the two haplogroups and one was central to haplogroup G. The seven haplotypes were common between Ethiopia, Kenya, Egypt, and Saudi Arabia populations, suggesting common maternal history and the introduction of goats into East Africa via Egypt and the Arabian Peninsula, respectively. While providing new mtDNA data from a historically important region, our results suggest extensive intermixing of goats mediated by human socio‐cultural and economic interactions. These have led to the coexistence of the two haplogroups in different geographic regions in Ethiopia resulting in a large caprine genetic diversity that can be exploited for genetic improvement.  相似文献   
42.
Glycophytic plants suffer from severe stress and injury when roots are exposed to high salinity in the rhizosphere. In contrast, the euhalophyte Salicornia europaea grows well at 200 mM NaCl and can withstand up to 1000 mM NaCl in the root zone. Analysis of gene expression profiles and the underlying molecular mechanisms responsible for this tolerance have been largely overlooked. Using the Illumina sequencing platform and the short-reads assembly programme Trinity, we generated a total of 40 and 39 million clean reads and further 140,086 and 122,728 unigenes from the 200 mM NaCl and 0 mM NaCl treated tissues of S. europaea roots, respectively. All unigenes in this study were functionally annotated within context of the COG, GO and KEGG pathways. Unigene functional annotation analysis allowed us to identify hundreds of ion transporters related to homeostasis and osmotic adaptation as well as a variety of proteins related to cation, amino acid, lipid and sugar transport. We found significant enrichment in response to stress including the functional categories of “antioxidant activity”, “catalytic activity” and “response to stimuli”. These findings represent for a useful resource for the scientific community working on salt tolerance mechanisms. Conversely, a total of 8639 EST-SSRs from 131,594 unigenes were identified and 4539 non-redundant SSRs primers pairs were developed. These data provide a good foundation for future studies on molecular adaptation mechanisms of euhalophytes roots under saline environments and will likely facilitate the identification of critical salt tolerance traits to be transferred in economically important crops.  相似文献   
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44.

Background

Gastrointestinal stromal tumours are rare (GIST). However, the incidence of GIST among neurofibromatosis type 1 (NF-1) patients is approximately 3.9-25%. GIST can present clinically in different ways such as abdominal pain, gastrointestinal bleeding and obstruction.

Case report

We present 51 year female patient admitted with Background of neurofibromatosis type 1 admitted with melena. OGD has been done and showed duodenitis with large volume fresh blood in distal duodenum but no obvious bleeding point. Exploratory laparotomy revealed smooth nodular masses on the serosal surface of jejunum. Small bowel resection and side-to-side anastomosis were performed. Histopathoogical examination revealed small bowel gasrointestinal stromal tumour with low risk malignant potential.

Conclusion

The incidence of GIST among neurofibromatosis type 1 (NF-1) patients is not uncommon and we should pay attention to gastrointestinal manifestation in such patients.
  相似文献   
45.
The purpose of the present study was to prepare intranasal delivery system of sildenafil citrate and estimate its relative bioavailability after nasal administration in rabbits to attain rapid onset of action with good efficacy at lower doses. Sildenafil citrate saturated solubility was determined in different solvents, cosolvents, and microemulsion systems. For nasal application, sildenafil citrate was formulated in two different systems: the first was a cosolvent system (S3) of benzyl alcohol/ethanol/water/Transcutol/taurodeoxy cholate/Tween 20 (0.5:16.8:47.7:15.9:1:18.1% w/w). The second was a microemulsion system (ME6) containing Oleic acid: Labrasol/Transcutol/water (8.33:33.3:16.66:41.66% w/w). The prepared systems were characterized in relation to their clarity, particle size, viscosity, pH, and nasal ciliotoxicity. In vivo pharmacokinetic performance of the selected system ME6 (with no nasal ciliotoxicity) was evaluated in a group of six rabbits in a randomized crossover study and compared to the marketed oral tablets. The targeted solubility (>20 mg/ml) of sildenafil citrate was achieved with cosolvent systems S1, S3, and S5 and with microemulsion systems ME3–ME6. The saturated solubility of sildenafil citrate in cosolvent system S3 and microemulsion system ME6 were 22.98 ± 1.26 and 23.79 ± 1.16 mg/ml, respectively. Microemulsion formulation ME6 showed shorter t max (0.75 h) and higher AUC(0-∞) (1,412.42 ng h/ml) compared to the oral tablets which showed t max equals 1.25 h and AUC(0-∞) of 1,251.14 ng h/ml after administration to rabbits at dose level of 5 mg/kg. The relative bioavailability was 112.89%. In conclusion, the nasal absorption of sildenafil citrate microemulsion was found to be fast, indicating the potential of nasal delivery instead of the conventional oral administration of such drug.  相似文献   
46.

Background

Microarray technology, as well as other functional genomics experiments, allow simultaneous measurements of thousands of genes within each sample. Both the prediction accuracy and interpretability of a classifier could be enhanced by performing the classification based only on selected discriminative genes. We propose a statistical method for selecting genes based on overlapping analysis of expression data across classes. This method results in a novel measure, called proportional overlapping score (POS), of a feature’s relevance to a classification task.

Results

We apply POS, along‐with four widely used gene selection methods, to several benchmark gene expression datasets. The experimental results of classification error rates computed using the Random Forest, k Nearest Neighbor and Support Vector Machine classifiers show that POS achieves a better performance.

Conclusions

A novel gene selection method, POS, is proposed. POS analyzes the expressions overlap across classes taking into account the proportions of overlapping samples. It robustly defines a mask for each gene that allows it to minimize the effect of expression outliers. The constructed masks along‐with a novel gene score are exploited to produce the selected subset of genes.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2105-15-274) contains supplementary material, which is available to authorized users.  相似文献   
47.
In the present study, the effect of arjunolic acid on testicular damage induced by intraperitoneal injection of rats with 7 mg/kg cisplatin was studied. Cisplatin induced a significant reduction in testicular weights, plasma testosterone, and testicular reduced glutathione levels in addition to a significant elevation of testicular malondialdehyde levels and testicular gene expressions of inducible nitric oxide synthase (iNOS), tumor necrosis factor‐α (TNF‐α), and p38 mitogen‐activated protein kinase (MAPK) when compared with the control group (p < 0.05). Lower tubular diameters and depletion of germ cells and irregular small seminiferous tubules with Sertoli cells only were observed in the cisplatin group. Arjunolic acid administration significantly corrected the changes in both biochemical and histopathological parameters. Arjunolic acid plays a significant protective role against cisplatin‐induced testicular injury by attenuating oxidative stress parameters along with downregulation of iNOS, TNF‐α, and p38‐MAPK testicular expressions.  相似文献   
48.
Heart failure (HF) is one of diabetic complications. This work was designed to investigate the possible modulatory effect of curcumin against streptozotocin‐induced diabetes and consequently HF in rats. Rats were divided into control, vehicle‐treated, curcumin‐treated, diabetic‐untreated, diabetic curcumin–treated, and diabetic glibenclamide–treated groups. Animal treatment was started 5 days after induction of diabetes and extended for 6 weeks. Diabetic rats showed significant increase in serum glucose, triglycerides, total cholesterol, low‐density lipoprotein‐cholesterol, very low density lipoprotein‐cholesterol, nitric oxide, lactate dehydrogenase, cardiac malondialdehyde, plasma levels of interleukin‐6, and tumor necrosis factor‐alpha, and also showed marked decrease in serum high‐density lipoprotein‐cholesterol, cardiac reduced glutathione, and cardiac antioxidant enzymes (catalase, superoxide dismutase, and glutathione‐S‐transferase). However, curcumin or glibenclamide treatment significantly mitigated such changes. In conclusion, curcumin has a beneficial therapeutic effect in diabetes‐induced HF, an effect that might be attributable to its antioxidant and suppressive activity on cytokines.  相似文献   
49.
BackgroundType 2 diabetes (T2DM) is a chronic metabolic disorder. Although therapeutic pharmaceutical agents continue to advance, herbal medicines are potential complementary treatments for the promotion of glucose homeostasis, with minimal adverse effects. Conventionally, ellagic acid (EA) has been utilized for the therapy of a range of pathologies owing to its anti-inflammatory and anti-diabetic actions.ObjectiveThe aim of this study is to determine the activity of EA on serum α-amylase and lipase titers, and on pancreatic tumor necrosis factor-α (TNF-α), proliferating cell nuclear antigen (PCNA) and interleukin-6 (IL-6) concentrations using the streptozocin-induced T2DM rodent model.MethodsEA extract synthesized from fresh strawberry fruit was employed for therapy. 50 adults male Wistar rats were randomized into either control, EA, diabetic, co-treated or post- treated cohorts.ResultsEA diminished fasting blood glucose levels, altered lipase, amylase, IL-6, PCNA and TNF- α expression and enhanced islet cell renewal, insulin, and immunoreactivities.ConclusionInflammatory indicators are elevated in the presence of T2DM. Extract of EA has overall tissue reparative and safeguarding properties, as indicated by the augmented β- cell population and enhanced glucose homeostasis. Thus, EA may be an innovative treatment approach for the maintenance of normoglycemia in individuals with T2DM.  相似文献   
50.
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