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901.

Background

Despite the fact that a large proportion of children with fever in Africa present at primary health care facilities, few studies have been designed to specifically study the causes of uncomplicated childhood febrile illness at this level of care, especially in areas like Zanzibar that has recently undergone a dramatic change from high to low malaria transmission.

Methods

We prospectively studied the aetiology of febrile illness in 677 children aged 2–59 months with acute uncomplicated fever managed by IMCI (Integrated Management of Childhood Illness) guidelines in Zanzibar, using point-of-care tests, urine culture, blood-PCR, chest X-ray (CXR) of IMCI-pneumonia classified patients, and multiple quantitative (q)PCR investigations of nasopharyngeal (NPH) (all patients) and rectal (GE) swabs (diarrhoea patients). For comparison, we also performed NPH and GE qPCR analyses in 167 healthy community controls. Final fever diagnoses were retrospectively established based on all clinical and laboratory data. Clinical outcome was assessed during a 14-day follow-up. The utility of IMCI for identifying infections presumed to require antibiotics was evaluated.

Findings

NPH-qPCR and GE-qPCR detected ≥1 pathogen in 657/672 (98%) and 153/164 (93%) of patients and 158/166 (95%) and 144/165 (87%) of controls, respectively. Overall, 57% (387/677) had IMCI-pneumonia, but only 12% (42/342) had CXR-confirmed pneumonia. Two patients were positive for Plasmodium falciparum. Respiratory syncytial virus (24.5%), influenza A/B (22.3%), rhinovirus (10.5%) and group-A streptococci (6.4%), CXR-confirmed pneumonia (6.2%), Shigella (4.3%) were the most common viral and bacterial fever diagnoses, respectively. Blood-PCR conducted in a sub-group of patients (n = 83) without defined fever diagnosis was negative for rickettsiae, chikungunya, dengue, Rift Valley fever and West Nile viruses. Antibiotics were prescribed to 500 (74%) patients, but only 152 (22%) had an infection retrospectively considered to require antibiotics. Clinical outcome was generally good. However, two children died. Only 68 (11%) patients remained febrile on day 3 and three of them had verified fever on day 14. An additional 29 (4.5%) children had fever relapse on day 14. Regression analysis determined C-reactive Protein (CRP) as the only independent variable significantly associated with CXR-confirmed pneumonia.

Conclusions

This is the first study on uncomplicated febrile illness in African children that both applied a comprehensive laboratory panel and a healthy control group. A majority of patients had viral respiratory tract infection. Pathogens were frequently detected by qPCR also in asymptomatic children, demonstrating the importance of incorporating controls in fever aetiology studies. The precision of IMCI for identifying infections requiring antibiotics was low.  相似文献   
902.
Some important optoelectronic properties of naphtho[2,1-b:6,5-b′]difuran (DPNDF) and its two derivatives have been limelighted by applying the density functional theory (DFT). Due to their low cost, high stability and earth abundance, the DPNDF and its derivatives are considered as potential organic semiconductor materials for their optoelectronics applications. Highly proficient derivatives are obtained systematically by attaching –CN (cyanide) to DPNDF at various sites. Our calculations indicate that DPNDF has a wide and direct band gap with an energy gap of 3.157 eV. Whereas the band gaps of its derivatives are found to be decreased by 88 meV for derivative “a” and 300 meV for derivative “b” as a consequence of p orbitals present in C and N atoms in derivative structures. The narrowing of the energy gap and density of states for the derivatives of DPNDF in the present investigation suggest that energy gap can be engineered for desirable optoelectronic applications via derivatives designing. Furthermore, their obtained results for optical parameters such as the dielectric and conductivity functions, reflectivity, refractive index, and the extinction coefficients endorses their aptness for optoelectronic applications.
Graphical Abstract Real part of dielectric function for derivative “b”
  相似文献   
903.
A study was carried out with maize as the test crop to investigate the bioavailability and leachability of heavy metals (HM) from HM-contaminated soils treated with composted manure. The application of composted manure increased the maize shoot growth by 32.3% and root growth by 30.5% compared with fresh manure. The concentration of HM in maize shoot varied in the order lead (Pb) > nickel (Ni) > zinc (Zn) > chromium (Cr) > copper (Cu) > cadmium (Cd). Whether for the shoot or root, the heavy metal concentrations decreased as the length of manure composting increased, but concentrations were higher in the root than the shoot. Composting decreased the bioavailability and leachability of HM and, hence, their export to the environment more effectively than direct use of fresh manure. Thus, the use of composted manure in place of fresh manure in polluted soils would be more beneficial for mitigating HM pollution.  相似文献   
904.
In the present work, the response surface methodology (RSM) based on a central composite rotatable design (CCRD), was used to determine optimum conditions for the extraction of antioxidant compounds from Origanum vulgare leaves. Four process variables were evaluated at three levels (31 experimental designs): methanol (70%, 80%, and 90%), the solute:solvent ratio (1:5, 1:12.5, 1:20), the extraction time (4, 10, 16 h), and the solute particle size (20, 65, 110 micron). Using RSM, a quadratic polynomial equation was obtained by multiple regression analysis for predicting optimization of the extraction protocol. Analysis of variance (ANOVA) was applied and the significant effect of the factors and their interactions were tested at 95% confidence interval. The antioxidant extract (AE) yield was significantly influenced by solvent composition, solute to solvent ratio, and time. The maximum AE was obtained at methanol (70%), liquid solid ratio (20), time (16 h), and particle size (20 micron). Predicted values thus obtained were closer to the experimental value indicating suitability of the model. Run 25 (methanol:water 70:30; solute:solvent 1:20; extraction time 16 h and solute particle size 20) showed highest TP contents (18.75 mg/g of dry material, measured as gallic acid equivalents) and DPPH radical scavenging activity (IC50 5.04 μg/mL). Results of the present study indicated good correlation between TP contents and DPPH radical scavenging activity. Results of the study indicated that phenolic compounds are powerful scavengers of free radical as demonstrated by a good correlation between TP contents and DPPH radical scavenging activity.  相似文献   
905.
906.
The Fanconi anemia (FA) core complex plays a central role in the DNA damage response network involving breast cancer susceptibility gene products, BRCA1 and BRCA2. The complex consists of eight FA proteins, including a ubiquitin ligase (FANCL) and a DNA translocase (FANCM), and is essential for monoubiquitination of FANCD2 in response to DNA damage. Here, we report a novel component of this complex, termed FAAP100, which is essential for the stability of the core complex and directly interacts with FANCB and FANCL to form a stable subcomplex. Formation of this subcomplex protects each component from proteolytic degradation and also allows their coregulation by FANCA and FANCM during nuclear localization. Using siRNA depletion and gene knockout techniques, we show that FAAP100-deficient cells display hallmark features of FA cells, including defective FANCD2 monoubiquitination, hypersensitivity to DNA crosslinking agents, and genomic instability. Our study identifies FAAP100 as a new critical component of the FA-BRCA DNA damage response network.  相似文献   
907.
N G-Nitro-l-arginine methyl ester hydrochloride (L-NAME) is a non-specific nitric oxide (NO) inhibitor and it has been used to eliminate the role of NO in many studies like animal models for hypertension. In this study, we aimed to investigate whether lisinopril treatment has any biochemical and/or histopathological effect on rat liver tissue in a L-NAME-induced hypertension model. Forty-eight 6-weeks-old male Spraque–Dawley rats were used in the study. The animals used in the study were randomly divided into four equal groups. To induce hypertension, L-NAME was added to drinking water at a concentration of 600 mg/l and each rat was given 75 mg/kg/day of L-NAME for 6 weeks. Tail cuff systolic blood pressure (SBP) was measured at first, third, and sixth weeks. There was a significant difference between the experiment groups and controls. In only lisinopril given and L-NAME plus lisinopril administered groups, each rat was given 10 mg/kg of lisinopril for 6 weeks. At the end of the study, the animals were sacrificed. Blood and tissue samples were collected for biochemical and histopathological analysis. It has been observed that mean NO level was significantly decreased in L-NAME given group (p<0.05). Mean ALT levels were significantly increased in lisinopril and L-NAME plus lisinopril given groups, when compared with the control group (p<0.05). AST levels were in normal range in all groups (p>0.05). Hepatocyte degeneration was prominent in lisinopril given group, whereas mononuclear cell infiltration was significant in L-NAME given groups. Although the beneficial effects in L-NAME-induced hypertension treatment, lisinopril can lead to some unexpected results like hepatocyte degeneration, serum enzyme level elevation, and slight mononuclear cell infiltration.  相似文献   
908.
Intragenic homozygous deletions in the Large gene are associated with a severe neuromuscular phenotype in the myodystrophy (myd) mouse. These mutations result in a virtual lack of glycosylation of α-dystroglycan. Compound heterozygous LARGE mutations have been reported in a single human patient, manifesting with mild congenital muscular dystrophy (CMD) and severe mental retardation. These mutations are likely to retain some residual LARGE glycosyltransferase activity as indicated by residual α-dystroglycan glycosylation in patient cells. We hypothesized that more severe LARGE mutations are associated with a more severe CMD phenotype in humans. Here we report a 63-kb intragenic LARGE deletion in a family with Walker-Warburg syndrome (WWS), which is characterized by CMD, and severe structural brain and eye malformations. This finding demonstrates that LARGE gene mutations can give rise to a wide clinical spectrum, similar as for other genes that have a role in the post-translational modification of the α-dystroglycan protein. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
909.
Polo box domain (PBD) from Polo-Like Kinase-1 (PLK-1) a cell cycle regulator is one of the important non-kinase targets implicated in various cancers. The crystal structure of PLK-1 PBD bound to phosphopeptide inhibitor is available and acylthiourea derivatives have been reported as potent PBD inhibitors. In this work, structure and ligand-based pharmacophore methods have been used to identify new PBD inhibitors. The binding of acylthiourea analogs and new inhibitors to PBD were assessed using molecular docking and molecular dynamics simulations to understand their binding interactions, investigate the complex stability and reveal the molecular basis for inhibition. This study provides the binding free energies and residue-wise contributions to decipher the essential interactions in the protein-inhibitor complementarity for complex formation and the design of new PBD inhibitors with better binding.

Communicated by Ramaswamy H. Sarma  相似文献   

910.
A potent male attractant of sweetpotato weevil helps in monitoring and control of sweetpotato weevil in many production areas around the world. At present, it has not been used in Malaysia. Cost of the components of a trapping system is a major constraint in the adoption of male lure‐baited trapping by growers in Malaysia. Seven field trapping experiments were conducted from February 2013 to November 2015 as part of an effort to develop a simple, easy to construct, cost‐effective and efficient sex pheromone‐baited trap acceptable for use by farmers in Malaysia for monitoring and control of sweetpotato weevil (Cylas formicarius Fabricius). Overall, sweetpotato weevil trap catch was significantly affected by the number of windows in the trap, the killing agent used in the trap and the position of the trap relative to sweetpotato foliage, while trap size and trap colour did not significantly affect trap catch. Trap catch was best in plastic pole traps made from polyethylene terephthalate, with four window opening to facilitate weevil entry, with detergent solution as a killing agent and with the trap positioned from 0 to 40 cm above the crop canopy level. In a comparison study with commercial trap designs, sex pheromone‐baited plastic pole traps caught 60%–78% more weevils than were caught in sex pheromone‐baited delta traps, wing traps or unitraps. Optimization of trap characteristics is important for improving the performance of pheromone‐baited traps for use in population monitoring or mass‐trapping efforts to minimize crop damage by sweetpotato weevil infestation.  相似文献   
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