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41.
To determine the effect of maternal anaemia on pregnancy outcome and describe its impact on infant haemoglobin level in the first 18 months of life, we conducted a prospective study of 617 pregnant women and their children in Benin. Prevalence of maternal anaemia at delivery was 39.5%, and 61.1% of newborns were anaemic at birth. Maternal anaemia was not associated with low birth weight [OR = 1.2 (0.6-2.2)] or preterm birth [OR = 1.3 (0.7-2.4)], whereas the newborn's anaemia was related to maternal anaemia [OR = 1.8 (1.2-2.5)]. There was no association between an infant's haemoglobin level until 18 months and maternal anaemia. However, malaria attacks during follow-up, male gender and sickle cell trait were all associated with a lower infant haemoglobin level until 18 months, whereas good infant feeding practices and a polygamous family were positively associated with a higher haemoglobin level during the first 18 months of life.  相似文献   
42.

Background

Previous work from our group demonstrated improved memory function in bariatric surgery patients at 12 weeks postoperatively relative to controls. However, no study has examined longer-term changes in cognitive functioning following bariatric surgery.

Methods

A total of 137 individuals (95 bariatric surgery patients and 42 obese controls) were followed prospectively to determine whether postsurgery cognitive improvements persist. Potential mechanisms of change were also examined. Bariatric surgery participants completed self-report measurements and a computerized cognitive test battery prior to surgery and at 12-week and 12-month follow-up; obese controls completed measures at equivalent time points.

Results

Bariatric surgery patients exhibited cognitive deficits relative to well-established standardized normative data prior to surgery, and obese controls demonstrated similar deficits. Analyses of longitudinal change indicated an interactive effect on memory indices, with bariatric surgery patients demonstrating better performance postoperatively than obese controls.

Conclusions

While memory performance was improved 12 months postbariatric surgery, the mechanisms underlying these improvements were unclear and did not appear attributable to obvious postsurgical changes, such as reductions in body mass index or comorbid medical conditions. Future studies employing neuroimaging, metabolic biomarkers, and more precise physiological measurements are needed to determine the mechanisms underlying memory improvements following bariatric surgery.  相似文献   
43.
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   
44.
The systemic mycoses like paracoccidioidomycosis and histoplasmosis, are the main cause of adrenal insufficiency in the countries where they arc endemic. In Venezuela an elevated frequency of these mycoses has been registered. The objective of this study was to evaluate the glucocorticoid adrenal function in patients with paracoccidioidomycosis and histoplasmosis hospitalized in the University Hospital "Ruiz y Pácz" of Ciudad Bolivar (Bolivar state) and in the Hospital "Luis Felipe Rojas Guevara", of El Tigre (Anzoátegui state), Venezuela, between January 2003 and January 2004. The test of fast stimulation with synthetic adrenocorticotrophin hormone (ACTH) was applied to a total of 12 patients with diagnosis of some of these mycoses and data of epidemiologic interest were taken. The proportion men:women was of 5:1, the average age was 35.1 +/- 0.37 years, similar to the control group. Basal plasmatic cortisol levels were within the normal rank in all the patients. After the injection of synthetic ACTH, an increase of plasmatic cortisol values in the same rank for patients with a normal adrenal function was observed, but it was significantly lower than the observed for the control group. These results suggest that there is an adrenal gland functional reserve diminution in patients with either Paracoccidioidomycosis or Histoplasmosis. In patients with systemic mycoses, it is important to evaluate the response to the test of fast stimulation with ACTH due to the frequency of impairment of the glucocorticoid adrenal function in our location.  相似文献   
45.
This work is focused on the synthesis of polycaprolactone nanoparticles, coated with chitosan, in a confined impinging jet reactor using the solvent displacement method. The role of the various reacting species was investigated, evidencing that a biocompatible polymer, for example, polycaprolactone, is required to support chitosan to obtain a monomodal particle size distribution, with low particle diameters. A surfactant is required to reduce the nanoparticle size (down to a mean diameter of about 260 nm) and obtain a positive zeta potential (about +31 mV), perfectly suitable for pharmaceutical applications. Different surfactants were tested, and Poloxamer 388 appeared to be preferable to polyvinyl alcohol. The effect of the concentration of Poloxamer 388 (in the range 0.5-5 mg mL?1) and of chitosan (in the range 1.5-5 mg mL?1) on both the mean particle size and zeta potential was also investigated, evidencing that chitosan concentration has the strongest effect on both parameters. Finally, the effect of solvent evaporation, quenching and feed flow rate was investigated, showing that the evaporation stage does not affect particle characteristics, quenching is required to avoid particle aggregation, and a minimum liquid flow rate of 80 mL min?1 is required in the considered reactor to minimize the particle size.  相似文献   
46.

Purpose

The aim of this study is to examine the prevalence and correlates of perceived health care stigma among female sex workers (FSWs) and men who have sex with men (MSM), including other stigma types, suicidal ideation, and participation in social activities.

Methods

FSWs (N = 350) and MSM (N = 330) aged ≥18 were recruited in Bobo-Dioulasso, Burkina Faso. Perceived health care stigma was defined as either ever being afraid of or avoiding health care services because someone might find out the participant has sex with men (for MSM) or sells sex (for FSW). Correlates of perceived health care stigma were examined using multivariable logistic regression.

Results

The prevalence of perceived health care stigma was 14.9% (52/350) and 24.5% (81/330) in FSWs and MSM, respectively. Among FSWs, experienced or social stigma, including verbal harassment (adjusted odds ratio [aOR] = 3.59, 95% confidence interval [CI] 1.48–8.71), feeling rejected by friends (aOR = 2.30, 95% CI 1.14–4.64), and feeling police refused to protect them (aOR = 2.58, 95% CI 1.27–5.25), was associated with perceived health care stigma. Among MSM, experiencing verbal harassment (aOR = 1.95, 95% CI 1.09–3.50) and feeling scared to walk in public (aOR = 2.93, 95% CI 1.47–5.86) were associated with perceived health care stigma.

Conclusions

In these key populations, perceived health care stigma was prevalent and associated with experienced and social stigmas. To increase coverage of effective HIV services, interventions should incorporate approaches to comprehensively mitigate stigma.  相似文献   
47.
Genetic analysis of circulating avian influenza viruses (AIVs) in wild birds at different geographical regions during the same period could improve our knowledge about virus transmission dynamics in natural hosts, virus evolution as well as zoonotic potential. Here, we report the genetic and molecular characterization of H6N2 influenza viruses isolated from migratory birds in Turkey, Egypt, and Uganda during 2017–2018. The Egyptian and Turkish isolates were genetically closer to each other than they were to the virus isolated from Uganda. Our results also suggest that multiple reassortment events were involved in the genesis of the isolated viruses. All viruses contained molecular markers previously associated with increased replication and/or pathogenicity in mammals. The results of this study indicate that H6N2 viruses carried by migratory birds on the West Asian/East African and Mediterranean/Black Sea flyways have the potential to transmit to mammals including humans. Additionally, adaptation markers in these viruses indicate the potential risk for poultry, which also increases the possibility of human exposure to these viruses.  相似文献   
48.
49.
50.
Whole-parasite malaria vaccines have shown promise in clinical trials. We recently reported the first human trial of a malaria vaccine based on Plasmodium falciparum genetically attenuated parasites (PfGAP). Herein we report for the first time that PfGAP induces prolonged functional humoral responses in humans. Six volunteers were exposed to 5 bites of PfGAP-infected mosquitoes followed by approximately 200 bites. Plasma collected from all volunteers 3 months after the last exposure efficiently inhibits invasion of hepatocytes by P. falciparum sporozoites. The level of inhibition observed is comparable to that attained using plasma collected after 4–5 intravenously administrations of high numbers of irradiated sporozoites, validating the potential of PfGAP malaria vaccines. Our data highlight the role of antibody responses in pre-erythrocytic stages of human malaria, and suggests that to be protective, malaria vaccines might need to elicit long-lasting functional antibodies in addition to cellular responses.  相似文献   
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