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51.
52.
In this work, we present a novel study on the development of an electrochemical biomimetic sensor to detect the ciprofloxacin (CIP) antibiotic. A chitosan gold nanoparticles decorated molecularly imprinted polymer (Ch-AuMIP) was used to modify the glassy carbon electrode (GCE) for preparation of the sensor. The Ch-AuMIP was characterized to understand various properties like chemical composition, morphology, roughness, and conduction using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and cyclic voltammetry (CV) respectively. Several experimental conditions affecting the Ch-AuMIP/GCE sensor such as the CIP removal agent, the extraction time, the volume of Ch-AuMIP drop-cast onto GCE and the rebinding time were studied and optimized. The Ch-AuMIP sensor sensitivity was studied in the concentration range of 1–100 μmol L−1 exhibiting a limit of detection of 210 nmol L−1. The synergistic combination of Au nanoparticles and Ch-MIP helps detect the CIP antibiotic with good sensitivity and selectivity, respectively. We investigated the selectivity aspect by using some possible interfering species and the developed sensing system showed good selectivity for CIP with a 66% response compared to the other compounds (≤45% response). The proposed sensing strategy showed its applicability for successful detection of CIP in real samples like tap water, mineral water, milk, and pharmaceutical formulation. The developed sensor showed good selectivity towards CIP even among the analogue molecules of Norfloxacin (NFX) and Ofloxacin (OFX). The developed sensor was successfully applied to determine the CIP in different samples with a satisfactory recovery in the range of 94 to 106%.

In this work, we present a novel study on the development of an electrochemical biomimetic sensor to detect the ciprofloxacin (CIP) antibiotic.  相似文献   
53.
Objectives:To assess the role of the Coronavirus Disease 2019 (COVID-19) pandemic in improving personal hygiene in Saudi Arabia.Methods:We administered a questionnaire distributed online between 19 and 28 May 2020 to determine alterations in personal hygiene practices during this pandemic compared to the pre-pandemic phase.Results:We included 211 respondents from the Kingdom of Saudi Arabia (KSA) in this study. Improvement at different levels was detected in all examined personal hygiene items compared to the pre-pandemic stage. The percentages of respondents who always washed their hands after coming back home (34.1%), used soap to wash their hands (58.8%), used a hand sanitizer outside (5.2%), wore a face masks while outside (1.4%) and washed their hands before preparing and/or eating food (74.9%) was increased before the pandemic to 89.6%, 90%, 63.5%, 59.2% and 89.1% during the pandemic, respectively. The percentage of respondents who never shake hands with people they know increased from 0% before the pandemic to 62.6% during the pandemic. The mean duration of washing hands with soap significantly increased from 13.31 seconds before the pandemic to 28.01 seconds during the pandemic (p<0.0001).Conclusion:The COVID-19 pandemic resulted in a noticeable improvement in the personal hygiene habits in Saudi Arabia mainly those related to COVID-19 prevention.  相似文献   
54.
The parental rotavirus strain 116E (G9P[11]) used to generate Rotavac® vaccine was isolated in 1986 in New Delhi. Thenceforward, there is no comprehensive report on diversity of G9 rotavirus strains from 116E; therefore, the present study evaluates the VP7 gene sequence diversity of G9 strains (retrieved from GenBank) from different geographical regions (1987–2016). Additionally, 22 recently collected G9 strains from Himachal Pradesh and Delhi (2013–2016) were included in the phylogenetic analysis. Interestingly, unlike 116E which belong to lineage-II all other G9 rotavirus including these 22 samples clustered together in a separate lineage (III). Further, six amino acid substitutions including one novel, K143M (epitope 7-2) different from 116E were detected mostly in the neutralization epitopes of VP7 protein (neutralization escape mutants). Overall, the accumulation of identified substitutions in VP7 epitopes and evolution of G9 strains in India may have impact on Rotavac® efficacy.  相似文献   
55.
Integration of infant- and child-feeding index (ICFI) addressing the multidimensional child-feeding practices into one age-specific summary index is gaining importance. This cross-sectional study was aimed at understanding the association between the ICFI and the nutritional status of 259 children, aged 6-23 months, who attended the paediatric outpatient department of the Dhaka Medical College Hospital in Bangladesh. The mean length-for-age z-score (LAZ) of children aged 12-23 months was significantly (p < 0.05) higher among those who were at the upper ICFI tercile compared to those who were at the middle or lower ICFI tercile (-2.01 and -3.20 respectively). A significant correlation was found between the ICFI and the LAZ (r = 0.24, p = 0.01 and r = 0.29, p = 0.01) in children aged 6-8-months and 12-23-months. Multivariable analysis, after adjusting for potential confounders, also found a significant association between the ICFI and the LAZ (beta = 0.13, p = 0.03). The predictive capability of the proposed ICFI on nutritional status of children, especially length-for-age, needs to be further evaluated prospectively among healthy children in the community.  相似文献   
56.
Background: The incidence of HIV and AIDS continues to be a source of great concern within universities in South Africa. Furthermore, university students constitute an important community in the intervention against the HIV/AIDS epidemic. Students in the age group of 15–24 years are at a greater risk of HIV infection than any other group in the country; yet, little is known about why they continue to engage in risky sexual practices. Objectives: This study was designed to explore the sexual behaviour of students in a metropolitan Durban University of Technology in KwaZulu-Natal to understand the social factors underlying their risk of HIV infection. Methods: This is a qualitative study that used cluster sampling where the population was stratified by campus and faculty. The study population was selected using a standard randomization technique. This was a part of a multi-phased research project aimed at providing a sero-prevalence baseline and an analysis of risk-taking behaviour at a Durban University of Technology in the eThekwini Metropolitan Municipality area. Results: The study highlights peer pressure among students as an influence in promoting high-risk sexual behaviour. Within this context, the findings revealed that university students lack the ability to negotiate risk-aware decisions especially regarding sexual relationships. Conclusion: This study draws attention to the perspectives of African university students regarding their risk-taking sexual practices and selected factors which influence such behaviour. The findings are not exhaustive in exploring contextual antecedents that shape students’ sexual practices. However, they provide an important basis in understanding key factors which expose students to HIV infections. The study provides insights into opportunities for further studies as well as preventative implications.  相似文献   
57.
Malaria is one of the serious diseases threatening human health in Pakistan and contributes to a large proportion of the total malaria deaths in South Asia. However, little is known about the nature and extent of genetic diversity of the malarial parasites circulating in Pakistan. This study was designed to assess the infection status of Plasmodium and the genetic diversity of Plasmodium vivax and Plasmodium falciparum by analyzing msp-3α, msp-3β and msp-1, msp-2 genes respectively using allele specific nested PCR and RFLP assays. For this purpose, 130 field isolates were collected from the individuals who exhibited clinical symptoms associated with malaria in the Kohat region of Khyber Pakhtoonkhwa (KPK), Pakistan. Among 130 blood samples collected, P. vivax was detected in 105/130 (80.8%) and P. falciparum in 21/130 (16.2%). Mixed infections with both parasites were detected in 4/130 (3%) of the isolates. A large number of distinguishable alleles were found for msp genetic markers: 10 alleles for msp-3α and seven for msp-3β with one mixed infection in case of msp-3β. The genotyping of P. falciparum showed that K1+MAD20 mixed genotype was dominant in msp-1 and FC27 in msp-2. The results collectively suggest that P. vivax and P. falciparum populations in this region are highly polymorphic and mixed infections are prevalent.  相似文献   
58.
Neurofibrillary degeneration appears to be required for the clinical expression of Alzheimer disease (AD) and related tauopathies. Given the polyetiology of these diseases and the pivotal involvement of neurofibrillary degeneration in their pathogenesis, inhibition of this lesion offers a promising therapeutic target. Studies from our laboratories have shown that there is a protein phosphorylation/dephosphorylation imbalance and that the microtubule associated protein tau is abnormally hyperphosphorylated in the brain of patients with AD and in this form it is the major protein subunit of paired helical filaments/neurofibrillary tangles (PHF/NFT). The abnormal tau which is polymerized into PHF/NFT neither promotes or inhibits in vitro microtubule assembly. In contrast the cytosolic abnormally hyperphosphorylated tau from AD brain, the AD P-tau neither associates with tubulin nor promotes in vitro microtubule assembly but instead it sequesters normal tau, MAP1 and MAP2 and inhibits microtubule assembly. The AD P-tau readily self-assembles in vitro into tangles of PHF/straight filaments under physiological conditions of protein concentration, pH, ionic strength and reducing conditions and this self assembly requires the abnormal hyperphosphorylation of this protein. The activity of phosphoseryl/phosphothreonyl protein phosphatase (PP)-2A which regulates the phosphorylation of tau, is compromised in AD brain. Thus, modulation of the activities of protein phosphatase-2A and tau kinases and inhibition of the sequestration of normal MAPs by AD P-tau offer promising therapeutic opportunities to inhibit neurofibrillary degeneration and the diseases characterized by this lesion.  相似文献   
59.
Detection and diagnosis of blood in feces and urine: an overview   总被引:5,自引:0,他引:5  
BACKGROUND: Detection of blood in feces or urine has long been regarded as an indicator of patient's state of health. The ease with which feces or urine may be obtained and patient's willingness to provide the specimen make detection of fecal occult blood or urine analysis one of the most commonly performed screening examinations. Historically, the inspection of feces or urine for diagnostic purpose has been practiced for centuries. Of late, management of renal or urinary tract abnormalities or investigation of anemia, gastrointestinal diseases and for early detection of colorectal cancer has assumed greater importance. METHODS: The never-ending list of techniques for the diagnosis of disorders producing bleeding such as urine microscopy, urine cytology, urine based marker test, cytoscopy, ultra sonography, computed tomography, magnetic resonance imaging, to mention a few, and four categories of detection of fecal occult blood namely, radioanalytical, physical, immunochemical and chemical methods makes the study very interesting. PURPOSE: This review attempts to overview various techniques, methods and methodologies for the diagnosis and detection of blood in feces and urine, in the direction of looking at past and current tests with an eye on future needs.  相似文献   
60.
Biochemical alterations in guinea pig lungs caused by hematite dust were followed at 150 days after intratracheal administration of the dust. In vivo dust exposure caused a significant increase in mitochondrial protein content and cytochrome c oxidase activity whereas diaphorase activity remained unaltered. Mitochondria from the exposed animals were apparently in a swollen state and their contraction profile upon the addition of ATP reflected permeability changes. However, in vitro dust caused no significant alterations. Significant increases in glycogen content along with an insignificant decrease in glycogen phosphorylase activity were also observed in hematite-treated guinea pig lungs. Decrease in drug-metabolizing enzymes such as aniline hydroxylase and tyrosine aminotransferase activities were also evident in the postmitochondrial fraction of the siderotic lungs. [3H]Leucine-incorporation studies showed increased protein synthesis in the postmitochondrial fraction. Increase in protein synthesis in mitochondria was only marginal whereas in whole homogenate it decreased considerably. Experiments employing dust tagged with radioactive iron indicated the rapid mobilization of iron from lung and its distribution to various organs. The presence of iron-binding protein was confirmed by employing Sephadex gel-filtration techniques.  相似文献   
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