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1.
The porcine circovirus type 2 (PCV2) is a swine infectious viral pathogen of great significance in global swine herds. It was recently detected at another Province of South Africa sequel to the first detection of North American‐like strain (PCV2a) at Gauteng about two decades ago, but there is a dearth of information about the genomic features and diversity of the viral strains in circulation within the country and the entire sub‐Saharan Africa region. To date, only one complete genome of the virus from South Africa is available on global data base. This current effort is therefore geared towards the full‐genome characterization of the circulating PCV2 strains in the pigs of Eastern Cape Province. With the use of conventional polymerase chain reaction method, fifteen complete PCV2 genomes were successfully amplified, sequenced and assembled from field samples obtained from non‐vaccinated pigs in the region. Neighbor Joining and Maximum Likelihood phylogenetic analyses of the ORF2 gene and full genomes unanimously showed that most of the assembled genomes (11) belong to genotype PCV2b. Furthermore, three of the characterized sequences formed clade with other reference mutant PCV2b and PCV2b subtype 1C (i.e. PCV2d) strains from the USA, China and South Korea. The last sequence, however, clustered with other reference strains belonging to PCV2 intermediate clade 2 (PCV2‐IM2), recently identified in a global PCV2 strains phylogenetic analysis. This study reports the first complete genome sequences of PCV2b, PCV2d and PCV2‐IM2 in pigs from South Africa, and it gives a possible insight into the genetic characteristics and variability of the viral strains presently in circulation within the country. It further emphasizes the need for more stringent measures in curtailing the introduction and spread of transboundary swine pathogens in the country and entire Southern African region.  相似文献   
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OBJECTIVES: The study assessed physicians' perceptions of HIV/AIDS patients and identified the determinants of physicians' attitudes toward communication with HIV/AIDS patients in Ile-Ife, Nigeria. METHODS: A semi-structured questionnaire was used to elicit information from 110 physicians in a cross-sectional survey, while in-depth interviews were conducted with 10 people living with HIV/AIDS (PLWHA) who had been previously admitted under the care of the physicians. Univariate, bivariate and multivariate analyzes were conducted. RESULTS: Although most physicians perceived PLWHA positively and 58% of them displayed a positive attitude toward communication with PLWHA under their care, the expectations of the patients concerning HIV/AIDS communication were not being met. Only 43% of physicians expressed any degree of comfort engaging PLWHA in lengthy discussions or communicating the diagnosis of HIV to patients. The strongest correlates of physicians' positive attitude were previous exposure to HIV/AIDS counseling, the number of HIV/AIDS patients treated per month, the number of years spent in the care of PLWHA, and the gender of the physicians (p < 0.05). CONCLUSIONS: Physicians in Ile-Ife, Nigeria are not adequately equipped by way of training to effectively meet the expectations of their patients concerning HIV/AIDS communication. The large number of PLWHA in the country calls for urgent attention to address this important aspect of care.  相似文献   
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Background

The management of childhood intussusception in our sub-region is still via surgical intervention. Currently, the gold standard of treatment is non-operative reduction. We sought to assess the suitability of hydrostatic (saline) reduction of intussusception in children in our institution.

Materials and methods

A prospective study was conducted between January 2016 and June 2017 in all children with ultrasound confirmed intussusception at a tertiary teaching hospital in Nigeria. All children excluding those with signs of peritonitis, bowel gangrene and intestinal prolapse were selected for ultrasound-guided hydrostatic reduction (USGHR). We allowed a maximum of three attempts at reduction.

Results

The age range was 3 months to 48 months with a mean of 10.8?±?9.1 months. Forty percent (N?=?18) presented after 24 h of onset of symptoms. The success rate of hydrostatic reduction with saline enema was 84.4% (N?=?38). Two (4.4%) perforations occurred during the procedure. Three (7.5%) patients had recurrent intussusception within six months. The duration of symptoms greater than 24 h, age and sex of patients did not influence successful reduction p?>?0.05. The duration of admission between those who had successful non-operative reduction and those who subsequently had operative reduction and or resection attained statistical significant difference, p?=?0.001. There was no mortality. We achieved a 68% decrease in the operative reduction of intussusception using USGHR as the primary modality of treatment.

Conclusion

Our study found out that USGHR is a suitable alternative for the treatment of childhood intussusception.
  相似文献   
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The CliRpath Excimer Laser System to Enlarge Lumen Openings (CELLO) registry included patients treated with modified excimer laser catheters for the endovascular treatment of peripheral artery disease affecting the superficial femoral artery (SFA) and proximal popliteal artery. The aim of this study was to assess, via intravascular ultrasound (IVUS) the dissections in the vessel wall following treatment with the laser catheters. IVUS grayscale images from the CELLO registry were systematically reviewed for dissections in the treated vessel segments by two investigators. Images from 33 patients; 66 pullbacks (1867 IVUS frames in 2 phases), were successfully matched frame-to-frame to evaluate identical segments of the treated vessels in the two phases; post-2 mm Turbo-Elite laser pilot channel creation and post Turbo-Booster laser atherectomy. Dissections were categorized as; (1) intimal, (2) medial, (3) intramural hematoma, and (4) adventitial according to the ACC Clinical Expert Consensus Document classification of dissections. An average of 57 frames was evaluated per pullback, giving a total of 3734 frames (1867 matched for pre-ablation (post channel creation) and post-ablation phases). Treatments with the modified Excimer laser catheters resulted in a significant increase in lumen area of 5.5?±?3.2-mm2 (95% CI 4.3–6.8, p?<?0.0001) and reduction in plaque plus media volume of ?10.6?±?36.0 mm3 (95% CI ?25.8 to 4.6, p?=?0.1619) whilst giving rise to mainly intramural hematoma formations post Turbo-Booster laser treatment in 55% of frames assessed and 24% medial dissections with less than 1% adventitial disruption. The Excimer laser based Turbo-Booster treatment of peripheral artery lesions resulted in significant plaque debulking and increased lumen diameter with negligible degree of adventitial layer injury.  相似文献   
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Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions.  相似文献   
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Development of homogenous metal matrix nanocomposites with uniform distribution of nanoreinforcement, preserved matrix nanostructure features, and improved properties, was possible by means of innovative processing techniques. In this work, Al-SiC nanocomposites were synthesized by mechanical milling and consolidated through spark plasma sintering. Field Emission Scanning Electron Microscope (FE-SEM) with Energy Dispersive X-ray Spectroscopy (EDS) facility was used for the characterization of the extent of SiC particles’ distribution in the mechanically milled powders and spark plasma sintered samples. The change of the matrix crystallite size and lattice strain during milling and sintering was followed through X-ray diffraction (XRD). The density and hardness of the developed materials were evaluated as function of SiC content at fixed sintering conditions using a densimeter and a digital microhardness tester, respectively. It was found that milling for 24 h led to uniform distribution of SiC nanoreinforcement, reduced particle size and crystallite size of the aluminum matrix, and increased lattice strain. The presence and amount of SiC reinforcement enhanced the milling effect. The uniform distribution of SiC achieved by mechanical milling was maintained in sintered samples. Sintering led to the increase in the crystallite size of the aluminum matrix; however, it remained less than 100 nm in the composite containing 10 wt.% SiC. Density and hardness of sintered nanocomposites were reported and compared with those published in the literature.  相似文献   
9.
The majority of clinical trials of neo‐adjuvant therapy for breast cancer have been conducted in resource‐rich countries. We chose Nigeria, a resource‐poor country, as the major site for a phase II feasibility open‐label multicenter clinical trial designed to evaluate the efficacy, safety, and tolerability of neo‐adjuvant capecitabine in locally advanced breast cancer (LABC). Planned treatment consisted of 24 weeks of capecitabine at a dose of 1,000 mg/m2 twice daily (2,000 mg/m2 total per day). The primary endpoints were overall, partial, complete clinical response rate (OCR, PCR, CCR) and complete pathologic response (cPR). A total of 16 patients were recruited from August 2007 to April 2010. The study was terminated early as a result of slow accrual. After the first three cycles of therapy, PCR were seen in five of 16 patients (31%; 95% CI 11–59%). Of the remaining 11 patients, eight had no response (NR) or stable disease (SD), and three had progressive disease (PD). Seven patients proceeded with further therapy of which had SD. OCR at the end of eight cycles was 44% (95% CI 20–70%). Clinical response and radiologic response by ultrasonomammography were highly concordant (spearman correlation 0.70). The most common adverse effect was Grade 1 hand–foot syndrome, which was seen in 75% of patients. Despite several limitations, we successfully carried out this phase II feasibility study of neo‐adjuvant capecitabine for LABC in Nigeria. Capecitabine monotherapy showed good overall response rates with minimal toxicity and further studies are warranted.  相似文献   
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