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71.
The present study was conducted to determine the prevalence of helminth eggs excreted in the faeces of stray cats, dogs and in soil samples. A total of 505 fresh samples of faeces (from 227 dogs and 152 cats) and soil were collected. The egg stage was detected via microscopy after the application of formalin–ether concentration technique. Genomic DNA was extracted from the samples containing hookworm eggs and used for further identification to the species level using real-time polymerase chain reaction coupled with high resolution melting analysis. Microscopic observation showed that the overall prevalence of helminth eggs among stray cats and dogs was 75.7% (95% CI = 71.2%–79.9%), in which 87.7% of dogs and 57.9% of cats were infected with at least one parasite genus. Five genera of heliminth eggs were detected in the faecal samples, including hookworms (46.4%), Toxocara (11.1%), Trichuris (8.4%), Spirometra (7.4%) and Ascaris (2.4%). The prevalence of helminth infections among stray dogs was significantly higher than that among stray cats (p < 0.001). Only three genera of helminths were detected in soil samples with the prevalence of 23% (95% CI = 15.1%–31%), consisting of hookworms (16.6%), Ascaris (4%) and Toxocara (2.4%). The molecular identification of hookworm species revealed that Ancylostoma ceylanicum was dominant in both faecal and soil samples. The dog hookworm, Ancylostoma caninum, was also detected among cats, which is the first such occurrence reported in Malaysia till date. This finding indicated that there was a cross-infection of A. caninum between stray cats and dogs because of their coexistent within human communities. Taken together, these data suggest the potential role of stray cats and dogs as being the main sources of environmental contamination as well as for human infections.  相似文献   
72.
73.

Rationale

There is little evidence for the efficacy of handwashing for prevention of influenza transmission in resource-poor settings. We tested the impact of intensive handwashing promotion on household transmission of influenza-like illness and influenza in rural Bangladesh.

Methods

In 2009–10, we identified index case-patients with influenza-like illness (fever with cough or sore throat) who were the only symptomatic person in their household. Household compounds of index case-patients were randomized to control or intervention (soap and daily handwashing promotion). We conducted daily surveillance and collected oropharyngeal specimens. Secondary attack ratios (SAR) were calculated for influenza and ILI in each arm. Among controls, we investigated individual risk factors for ILI among household contacts of index case-patients.

Results

Among 377 index case-patients, the mean number of days between fever onset and study enrollment was 2.1 (SD 1.7) among the 184 controls and 2.6 (SD 2.9) among 193 intervention case-patients. Influenza infection was confirmed in 20% of controls and 12% of intervention index case-patients. The SAR for influenza-like illness among household contacts was 9.5% among intervention (158/1661) and 7.7% among control households (115/1498) (SAR ratio 1.24, 95% CI 0.92–1.65). The SAR ratio for influenza was 2.40 (95% CI 0.68–8.47). In the control arm, susceptible contacts <2 years old (RRadj 5.51, 95% CI 3.43–8.85), those living with an index case-patient enrolled ≤24 hours after symptom onset (RRadj 1.91, 95% CI 1.18–3.10), and those who reported multiple daily interactions with the index case-patient (RRadj 1.94, 95% CI 1.71–3.26) were at increased risk of influenza-like illness.

Discussion

Handwashing promotion initiated after illness onset in a household member did not protect against influenza-like illness or influenza. Behavior may not have changed rapidly enough to curb transmission between household members. A reactive approach to reduce household influenza transmission through handwashing promotion may be ineffective in the context of rural Bangladesh.

Trial Registration

ClinicalTrials.gov NCT00880659  相似文献   
74.
We studied the in-vitro/in-vivo interactions between HCC/HSCs in early and advanced fibrosis-models. Hep3B-mono-cultures secreted high levels of αFetoProtein (αFP). Human-HSCs co-cultured with Hep3B-cells significantly decreased αFP and increased their apoptosis. Confocal-microscopy demonstrated Hep3B-phagocytosis inside the HSCs suggesting a direct cellular-contact mediating anti-tumor effect. Leptin-activated HSCs further suppressed Hep3B-cells with increased ROS and decreased GSH. Following intrahepatic-Hep3B-cell injections, mice with established “advanced liver-fibrosis”; had higher tumor-size and αFP serum-levels as compared to non-fibrotic livers. Mice with “early liver-fibrosis”, which initiated post tumor induction had a significant decrease in tumor and high Malondialdehyde (MDA) serum levels compared to advanced-fibrosis animals.At early-fibrosis stages, activated-HSCs express direct anti-tumor effects by phagocytosis and apoptosis of tumor-cells mediated by oxidative stress.  相似文献   
75.
Five local Malaysian patients with clinical manifestations consistent with lymphatic filariasis were referred to our medical centre between 2003 and 2006. Although no microfilariae (mf) were detected in their nocturnal blood samples, all were diagnosed to have lymphatic filariasis on the basis of clinical findings and positive serology results. PCR on their blood samples revealed that two of the patients were infected with Brugia pahangi, an animal filarial worm hitherto not known to cause human disease in the natural environment. All the patients were successfully treated with anti-filarial drugs: four patients were treated with a combination of diethylcarbamazine (DEC) and albendazole, and one with doxycycline. Four of them were residents of Petaling Jaya, a residential suburbia located 10 km southwest of Kuala Lumpur city, Malaysia. The fifth patient was a frequent visitor of the suburbia. This suburbia has no history or record of B. malayi infection. The most likely vector of the worm was Armigeres subalbatus as extensive entomological surveys within the suburbia revealed only adult females of this mosquito species were infected with B. pahangi larvae. Wild monkeys caught in the suburbia were free from B. pahangi mf, but domestic cats were mf positive. This suggests that infected cats might be the source of the zoonotic infection in the suburbia.  相似文献   
76.
Mahmud A  Discher DE 《IUBMB life》2011,63(8):607-612
Systemic delivery of therapeutic agents via inhalation of particulates remains an attractive, noninvasive means of administration due to the possibilities of high bioavailability and high patient compliance. Optimization of particle shapes and particle properties for deep lung deposition after inhalation continues to be one of the key challenges. Here, we review several aspects of nanoparticle design for deep lung deposition as well as the nature and extent of translocation through the air-blood barrier for local or systemic vascular targeting. We describe filamentous influenza virus in comparison to worm-like "filomicelle" polymers as one example of a nature inspired design.  相似文献   
77.
Cyclic peptides are attractive candidates for synthetic affinity ligands due to their favorable properties, such as resistance to proteolysis, and higher affinity and specificity relative to linear peptides. Here we describe the discovery, synthesis and characterization of novel cyclic peptide affinity ligands that bind the Fc portion of human Immunoglobulin G (IgG; hFc). We generated an mRNA display library of cyclic pentapeptides wherein peptide cyclization was achieved with high yield and selectivity, using a solid‐phase crosslinking reaction between two primary amine groups, mediated by a homobifunctional linker. Subsequently, a pool of cyclic peptide binders to hFc was isolated from this library and chromatographic resins incorporating the selected cyclic peptides were prepared by on‐resin solid‐phase peptide synthesis and cyclization. Significantly, this approach results in resins that are resistant to harsh basic conditions of column cleaning and regeneration. Further studies identified a specific cyclic peptide—cyclo[Link‐M‐WFRHY‐K]—as a robust affinity ligand for purification of IgG from complex mixtures. The cyclo[Link‐M‐WFRHY‐K] resin bound selectively to the Fc fragment of IgG, with no binding to the Fab fragment, and also bound immunoglobulins from a variety of mammalian species. Notably, while the recovery of IgG using the cyclo[Link‐M‐WFRHY‐K] resin was comparable to a Protein A resin, elution of IgG could be achieved under milder conditions (pH 4 vs. pH 2.5). Thus, cyclo[Link‐M‐WFRHY‐K] is an attractive candidate for developing a cost‐effective and robust chromatographic resin to purify monoclonal antibodies (mAbs). Finally, our approach can be extended to efficiently generate and evaluate cyclic peptide affinity ligands for other targets of interest. Biotechnol. Bioeng. 2013; 110: 857–870. © 2012 Wiley Periodicals, Inc.  相似文献   
78.
Six amino acids viz. DL-methionine, DL-valine, DL-serine, DL-phenylalanine, L-proline and L-histidine were tested against root knot of tomato caused by Meloidogyne javanica. All amino acids showed significant response in plant growth characters with corresponding reduction in the number of galls, adult females, egg masses and juvenile stages within the treated plants. DL-phenylalanine gave significantly higher response in reducing the hatch of egg masses and survival of juveniles in in vitro test compared to control. The highest plant growth and maximum reduction of galling incidence of tomato were recorded in the DL-phenylalanine- treated plants followed by L-proline and L-histidine. All the amino acids gave positive response in suppressing the development of the nematode in the treated plants.  相似文献   
79.
80.
In recent literature, prospective application of life cycle assessment (LCA) at low technology readiness levels (TRL) has gained immense interest for its potential to enable development of emerging technologies with improved environmental performances. However, limited data, uncertain functionality, scale up issues and uncertainties make it very challenging for the standard LCA guidelines to evaluate emerging technologies and requires methodological advances in the current LCA framework. In this paper, we review published literature to identify major methodological challenges and key research efforts to resolve these issues with a focus on recent developments in five major areas: cross‐study comparability, data availability and quality, scale‐up issues, uncertainty and uncertainty communication, and assessment time. We also provide a number of recommendations for future research to support the evaluation of emerging technologies at low technology readiness levels: (a) the development of a consistent framework and reporting methods for LCA of emerging technologies; (b) the integration of other tools with LCA, such as multicriteria decision analysis, risk analysis, technoeconomic analysis; and (c) the development of a data repository for emerging materials, processes, and technologies.  相似文献   
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