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11.
The housefly, Musca domestica L., is one of the most common insects, associated with vectoring of various etiological agents. In order to search for effective control agent, the essential oil of sweet orange [Citrus sinensis (L.) Osbeck] was evaluated for its insecticidal activity against the larvae and pupae of housefly using contact toxicity and fumigation bioassays. In the contact toxicity assay, lethal concentration, LC50 of C. sinensis essential oil against housefly larvae, varied between 3.93 and 0.71 μl/cm2 for different observation days, while lethal time, LT50, varied between 5.8 to 2.3 days. Mortality of larvae were significant with different concentrations (F = 2.79, df = 4, P < 0.05) and time (F = 6.69, df = 3, P < 0.01). In fumigant assay for housefly larvae, LC50 of 71.2 and 52.6 μl/l was obtained in 24 and 48 h, respectively. Scanning electron microscopy of oil treated larvae revealed extreme dehydration and surface distortion while control larvae were free from any of the above symptoms and presented smooth surface, conforming effect of essential oil on housefly larvae. Percentage inhibition rate of oil against housefly pupae was 27.3–72.7% for contact toxicity and 46.4–100% for fumigation assay. Compositional analysis of C. sinensis essential oil using gas chromatography/mass spectrometry (GC-MS) revealed d-limonene (73.24%), α-pinene (5.86%) and myrcene (4.45%) as major components whereas its vapour profile (solid-phase micro extraction-GC/MS) was dominated by d-limonene at 92.57%. Significant activity of C. sinensis essential oil against larvae and pupae of housefly, pave the way for its use as eco-friendly housefly control measure.  相似文献   
12.
Mutations in the cystathionine beta‐synthase (CBS) gene are the cause of classical homocystinuria, the most common inborn error in sulfur metabolism. The c.797 G>A (p.R266K) mutation in CBS was originally described in several Norwegian pyridoxine responsive CBS deficient patients, and heterologous gene expression studies have shown that the protein has near wild‐type levels of enzyme activity. Here, we characterize a transgenic mouse lacking endogenous Cbs and expressing p.R266K human CBS protein from a zinc inducible metallothionein promoter (Tg‐R266K Cbs‐/‐). Unlike mice expressing other mutant CBS alleles, the Tg‐R266K transgene is unable to efficiently rescue neonatal lethality of Cbs‐/‐ on a C57BL/6J background. On a C3H/HeJ background, zinc‐induced Tg‐R266K Cbs‐/‐ mice express CBS mRNA, but have very low levels of CBS protein and enzyme activity, resulting in extreme elevations in serum total homocysteine (tHcy). Treatment with pyridoxine did not have any appreciable effect on tHcy, indicating this allele is not pyridoxine responsive in mice. However, treatment with the proteasome inhibitor bortezomib resulted in an 97% reduction in tHcy and a 2381% increase in liver CBS activity. These studies show that the p.R266K mutation causes increased proteasomal degradation in vivo, and that treatments that stabilize the protein can be used to reverse its effect.  相似文献   
13.
This paper presents findings on hysterectomy prevalence from a 2010 cross-sectional household survey of 2,214 rural and 1,641 urban, insured and uninsured women in low-income households in Ahmedabad city and district in Gujarat, India. The study investigated why hysterectomy was a leading reason for use of health insurance by women insured by SEWA, a women's organisation that operates a community-based health insurance scheme. Of insured women, 9.8% of rural women and 5.3% of urban women had had a hysterectomy, compared to 7.2% and 4.0%, respectively, of uninsured women. Approximately one-third of all hysterectomies were in women younger than 35 years of age. Rural women used the private sector more often for hysterectomy, while urban use was almost evenly split between the public and private sectors. SEWA's community health workers suggested that such young women underwent hysterectomies due to difficulties with menstruation and a range of gynaecological morbidities. The extent of these and of unnecessary hysterectomy, as well as providers' attitudes, require further investigation. We recommend the provision of information on hysterectomy as part of community health education for women, and better provision of basic gynaecological care as areas for advocacy and action by SEWA and the public health community in India.  相似文献   
14.
Abstract

A cross-linked hydrogel was synthesized using a hybrid backbone of karaya gum starch and grafted with polyacrylic acid. It showed a maximum swelling ratio (SR) of 30.5?g/g at pH 10 and was explored as an oral drug delivery carrier using paracetamol and aspirin as model drugs. In vitro release experiments revealed that maximum drug release at pH 7.4 in comparison to pH 1.2 (simulated intestinal vs gastric fluid) and neutral medium. The release profiles of these drugs showed no initial burst. It also showed good hemocompatibilty and non-cytotoxicity for its employment as a site specific drug delivery agent.  相似文献   
15.
Locked-in syndrome is characterized by upper motor neuron quadriplegia, paralysis of lower cranial nerves, bilateral horizontal gaze palsy and anarthria, with preserved consciousness. It is due to a ventral pontine lesion following a basilar artery occlusion. We report the first Indian case report of locked-in syndrome, a 10-year old girl in whom the syndome was preceded by a ‘herald hemiparesis’. Although the exact etiology for the basilar artery occlusion could not be determined, treatment with low molecular weight heparin and warfarin was followed by partial recovery.  相似文献   
16.
A rapid, selective and stability indicating high performance liquid chromatographic method was developed and validated for the estimation of venlafaxine in pharmaceutical dosage forms. The analysis was done on a Spherisorb C8 (4.6×250 mm, 5 μm) column. The mobile phase consisted of acetonitrile:sodium dihydrogen orthophosphate [0.04 M], pH 6.8 (75:25) at a flow rate of 1.5 ml/min. Detection was carried out at a wavelength of 224 nm. The developed method was found to give good separation between the pure drug and the degraded product. The polynomial regression data for the calibration plots showed good linear relationship in the concentration range of 1–10 μg/ml with r=0.9999. The method was validated for precision, accuracy, ruggedness and recovery. The minimum detectable and minimum quantifiable amounts were found to be 150 and 600 ng/ml, respectively. The drug was stable under basic and oxidative conditions. However, the sample treated with acid showed an additional peak at a retention time of 4.32 min other than the main peak at a retention time of 5.32 min. Statistical analysis proves that the method is reproducible and selective for the estimation of venlafaxine. As the method could effectively separate the drug from the degradation product, it can be employed as a stability indicating one.  相似文献   
17.
Previous studies have identified low patient accrual in large-scale cancer clinical trials, particularly for underrepresented groups, such as ethnic minorities, females, and patients >65 years. As there have been few studies examining participation in cancer genetics epidemiologic research, our objective was to identify clinical and demographic factors predicting enrollment in these studies. A total of 1,111 patients diagnosed with colorectal cancer presenting to a gastrointestinal oncology clinic were approached to enroll in a study investigating the role of the MSH6 gene in familial colorectal cancer. Patient consent was sought for providing a blood specimen for DNA analysis and review of medical records/tumor specimens and contacting family members to confirm the family history of cancer. Seven predictor variables for enrollment (age, sex, ethnicity, family history of colorectal cancer in a first-degree relative, presence of children, insurance type, and type of visit) were analyzed using logistic regression analysis to determine the effect on decision to enroll. Of 1,111 patients approached, 696 (62.6%) enrolled in the study. Of these approached individuals, 4.2% were of nonwhite ethnicity and 33.5% were age > or =65 years. Patients of white ethnicity [odds ratio (OR), 2.10; P = 0.018], males (OR, 1.47; P = 0.002), those ages < or =65 years (OR, 1.42; P = 0.009), and those with a first-degree relative with colorectal cancer (OR, 1.57; P = 0.005) were significantly more likely to enroll. Fewer than 4% of all participants denied permission for the study researchers to access information from medical records or to be recontacted by researchers to discuss the enrollment of additional family members. Our data suggest that, once subjects decided to enroll, the majority (88%) was comfortable with consenting to all study components, including the creation of cell lines and future recontact. Low participation rates for ethnic minorities, females, and elderly patients are similar for both cancer genetics and clinical trial studies.  相似文献   
18.
Environmental tobacco smoke (ETS) poses an underappreciated risk to adolescent health. This study examined perceptions of adolescents (n = 574) regarding ETS. About one half (54%) were exposed to ETS the previous week, and one third (30%) were exposed to 3 or more hours of ETS the past week. Concurrently, 29% believed that breathing someone else's cigarette smoke had little or no effect on their health. Most adolescents (56%) believed that smoking should not be allowed in restaurants without bars but were less supportive of prohibiting smoking in restaurants with bars (20%) or in bars (14%). Two thirds (69%) of adolescents believed that the government should be involved in making laws that protect the health of people who work in bars and restaurants. Almost one half (49%) believed that the government should be involved in passing laws that make it illegal for people to smoke in public places. Odds ratios revealed that females, nonwhites, younger students, nonsmoking students, and students who believed that ETS exposure had a moderate or major effect on health were statistically significantly more likely to support clean indoor air ordinances in select locations compared to males, whites, older students, students who smoke, and students who perceived that ETS exposure has little to no effect on health.  相似文献   
19.
Colorectal cancer accounts for more than 10% of all cancer deaths but is curable, if detected early. We reported previously on a stool-based screening test in which DNA from stool samples is subjected to genome analysis; sensitivity of the test has been limited in part by inefficiency of retrieving DNA from stool. Our aim was to test the impact of a new purification method that would increase the yield of human DNA from stool. DNA from 86 cancer and 100 non-cancer subjects (diagnosed by colonoscopy) were purified from stool with a new method for DNA recovery based on sequence-specific capture with acrylamide gel immobilized capture probes as well as with a previously developed magnetic bead-capture procedure. The new purification method gives an average 5.4-fold increase in the quantity of human DNA that can routinely be retrieved from fecal samples. The increased recovery of DNA corresponds with an increase in assay sensitivity from 53% (CI: 42 to 64%) to 70% (CI: 59 to 79%); P = 0.0005 (by McNemar's test), with no change in specificity. The newly developed sample preparation method mitigates a major problem in detecting rare cancer-associated genetic changes in heterogeneous clinical samples such as stool.  相似文献   
20.
There is an emerging evidence that plumbagin (5-hydroxy-2-methyl-1, 4-naphthoquinone) may have potential as a chemotherapeutic agent. However, the growth inhibitory mechanisms of plumbagin have remained unexplored. The aim of the study was to determine whether plumbagin-induced cell death in human cervical cancer cell line, ME-180, exhibited biochemical characteristics of apoptosis and to check whether N-acetyl-l-cysteine (NAC), which is a free radical scavenger, can reverse the cytotoxic effects of plumbagin. It can be concluded from the results that plumbagin inhibits the growth of ME-180 cells in a concentration and time-dependent manner. The cytotoxic effect of plumbagin induced cell death is through the generation of reactive oxygen species (ROS) and subsequent induction of apoptosis as demonstrated by the present data. Treatment of cells with plumbagin caused loss of mitochondrial membrane potential (DeltaPsi(m)), and morphological changes characteristic of apoptosis, such as the translocation of phosphatidyl serine, nuclear condensation, and DNA fragmentation. Moreover, plumbagin-induced apoptosis involved release of mitochondrial cytochrome c and apoptosis inducing factor (AIF), thus activation of caspase-dependent and -independent pathways, as shown by the plumbagin-mediated activation of caspase-3 and -9. Our results also show that pretreatment of ME-180 cells with NAC blocks plumbagin-induced loss of DeltaPsi(m) and subsequent release of cytochrome c, AIF, and caspase-9 and -3 activation, thus inhibiting the apoptotic ability of plumbagin.  相似文献   
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