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31.
Oral cancer is a major cause of cancer morbidity and mortality worldwide and is prevalent in most areas where tobacco related practices are observed. Essential elements play a role in many biochemical reactions as a micro-source and there is growing evidence that their concentrations are altered on the onset and progress of malignant disease. In this study the levels of copper (Cu), zinc (Zn), selenium (Se) and molybdenum (Mo) in serum of patients with oral sub mucous fibrosis (OSMF) (n = 30) and oral squamous cell carcinoma (OSCC) (n = 30); were determined and the alterations of these critical parameters were analyzed in comparison with controls (n = 30) to identify predictors amongst these parameters for disease occurrence and progression. The serum Cu and Zn were established using Flame Atomic Absorption Spectrometry. Serum estimation of Se and Mo was done by graphite furnace atomic absorption spectrometry (GFAAS). Data analysis revealed a marked, progressive and significant increase in Cu levels in precancer (OSMF) and cancer (OSCC) groups as compared to the normal group. The level of Zn in serum was slightly elevated in OSMF and OSCC though not statistically significant. Cu/Zn ratio was slightly but not significantly elevated. Serum levels of Se and Mo were significantly decreased in the precancer and cancer groups as compared to the normals.  相似文献   
32.

Background

Optimum efficiency of the folate pathway is considered essential for adequate ovarian function. 677 C>T substitution in the 5, 10-methylene tertrahydrofolatereductase (MTHFR) gene compromises activity of the MTHFR enzyme by about 50%. The significance of correlation between 677C>T substitution and PCOS remains dubious due to the low power of published studies.

Methods and Results

We analyzed MTHFR 677 C>T site in ethnically two different PCOS case-control groups (total 261 cases and 256 controls) from India. The data analysis revealed a lack of association between this polymorphism and PCOS [OR = 1.11 (95%CI = 0.71–1.72), P = 0.66]. Group-wise analysis on the basis of ethnicity also revealed no association in any of the ethnic groups [Indo-Europeans, P = 1; Dravidians, P = 0.70]. Homocysteine levels did not differ significantly between cases (15.51 μmol/L, SD = 2.89) and controls (15.89 μmol/L, SD = 2.23). We also undertook a meta-analysis on 960 cases and 1028 controls, which suggested a significant association of the substitution with PCOS in the dominant model of analysis (OR = 1.47 (95%CI = 1.04–2.09), P = 0.032]. Trial sequential analysis corroborated findings of the traditional meta-analysis. However, we found that the conclusions of meta-analysis were strongly influenced by studies that deviated from the Hardy Weinberg equilibrium. A careful investigation of each study and a trial sequential analysis suggested that 677 C>T substitution holds no clinical significance in PCOS in most of the populations.

Conclusion

In conclusion, MTHFR 677 C>T polymorphism does not affect PCOS risk in India. The association seen in the meta-analysis is due to an outlier study and studies showing deviation from the Hardy Weinberg equilibrium.  相似文献   
33.

Background

The World Health Organization recommends direct observation of treatment (DOT) to support patients with tuberculosis (TB) and to ensure treatment completion. As per national programme guidelines in India, a DOT provider can be anyone who is acceptable and accessible to the patient and accountable to the health system, except a family member. This poses challenges among children with TB who may be more comfortable receiving medicines from their parents or family members than from unfamiliar DOT providers. We conducted a non-inferiority trial to assess the effect of family DOT on treatment success rates among children with newly diagnosed TB registered for treatment during June–September 2012.

Methods

We randomly assigned all districts (n = 30) in Gujarat to the intervention (n = 15) or usual-practice group (n = 15). Adult family members in the intervention districts were given the choice to become their child’s DOT provider. DOT was provided by a non-family member in the usual-practice districts. Using routinely collected clinic-based TB treatment cards, we compared treatment success rates (cured and treatment completed) between the two groups and the non-inferiority limit was kept at 5%.

Results

Of 624 children with newly diagnosed TB, 359 (58%) were from intervention districts and 265 (42%) were from usual-practice districts. The two groups were similar with respect to baseline characteristics including age, sex, type of TB, and initial body weight. The treatment success rates were 344 (95.8%) and 247 (93.2%) (p = 0.11) among the intervention and usual-practice groups respectively.

Conclusion

DOT provided by a family member is not inferior to DOT provided by a non-family member among new TB cases in children and can attain international targets for treatment success.

Trial Registration

Clinical Trials Registry–India, National Institute of Medical Statistics (Indian Council of Medical Research) CTRI/2015/09/006229  相似文献   
34.
35.
Context: Asenapine maleate (ASPM) is an antipsychotic drug for the treatment of schizophrenia and bipolar disorder. Extensive metabolism makes the oral route inconvenient for ASPM.

Objective: The objective of this study is to increase ASPM bioavailability via transdermal route by improving the skin permeation using combined strategy of chemical and nano-carrier (transfersomal) based approaches.

Materials and methods: Transfersomes were prepared by the thin film hydration method using soy-phosphatidylcholine (SPC) and sodium deoxycholate (SDC). Transfersomes were characterized for particle size, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency, surface morphology, and in vitro skin permeation studies. Various chemical enhancers were screened for skin permeation enhancement of ASPM. Optimized transfersomes were incorporated into a gel base containing suitable chemical enhancer for efficient transdermal delivery. In vivo pharmacokinetic study was performed in rats to assess bioavailability by transdermal route against oral administration.

Results and discussion: Optimized transfersomes with drug:SPC:SDC weight ratio of 5:75:10 were spherical with an average size of 126.0?nm, PDI of 0.232, ZP of??43.7?mV, and entrapment efficiency of 54.96%. Ethanol (20% v/v) showed greater skin permeation enhancement. The cumulative amount of ASPM permeated after 24?h (Q24) by individual effect of ethanol and transfersome, and in combination was found to be 160.0, 132.9, and 309.3?μg, respectively, indicating beneficial synergistic effect of combined approach. In vivo pharmacokinetic study revealed significant (p?Conclusion: Dual strategy of permeation enhancement was successful in increasing the transdermal permeation and bioavailability of ASPM.  相似文献   
36.
The multivariate statistical methods (cluster analysis and discriminant analysis [DA]) are used to evaluate the quality of water spatiotemporally in the Brahmani River basin. A total of 15 water quality indicators (pH, Chloramines, Sodium, Sulfate, Phosphate, Potassium, Boron, Fluoride, Cadmium, Copper, Lead, Nickel, Zinc, Iron, and Total Chromium) are collected for 13 years in two seasons (the dry and the wet season) from nine sampling stations. These stations are grouped into four clusters (Considerable [Co], Low Pollution [LP], Moderate Pollution [MP], and Extreme Pollution [(EP]) by hierarchical agglomerative cluster analysis based on the similarities of water quality characteristics. The nine important influencing discriminating water quality indicators are extracted by stepwise method of temporal DA,where as eight important influencing indicators for dry season and eight indicators (Potassium, Phosphate, Fluoride, Copper, Lead, Nickel, Iron, and Total Chromium) for wet season are found out by the spatial DA. The pollution status in the river basin was observed from overall trend in (Considerable) Co to (Extreme Pollution) EP regions. The study could be very useful in prioritizing the important sites for water resources and pollution management.  相似文献   
37.
The skin secretions of Australian tree frogs are rich in peptides with potential antimicrobial activity. They interrupt bacterial cell membranes, although precisely how and whether all peptides have the same mechanism is not known. The interactions of three of these peptides—aurein 1.2, maculatin 1.1, and caerin 1.1 with supported phospholipid bilayers—are examined here using quartz crystal microbalance and atomic force microscopy. These approaches enabled us to reveal variations in material structure and density as a function of distance from the sensor surface when comparing mass sensorgrams over a range of harmonics of the natural resonance of the sensor crystal and hence obtain for the first time to our knowledge a mechanistic assessment of membrane disruption. We found that caerin inserted into the bilayer in a transmembrane manner, regardless of concentration and phospholipid composition consistent with a pore-forming mechanism. In contrast, maculatin and aurein interacted with membranes in a concentration-dependent manner. At low concentrations (<5 μM), maculatin exhibited transmembrane incorporation whereas aurein was limited to surface association. Upon reaching a threshold value of concentration, both peptides lysed the membrane. In the case of maculatin, the lysis progressed in a slow, concentration-dependent manner, forming mixed micelles, as shown by atomic force microscopy imaging. Aurein-induced lysis proceeded to a sudden disruption, which is consistent with the “carpet” mechanism. Both maculatin and aurein exhibit specificity toward phospholipids and thus have potential as candidates as antimicrobial drugs.  相似文献   
38.
Adhesion to the extracellular matrix regulates numerous changes in the actin cytoskeleton by regulating the activity of the Rho family of small GTPases. Here, we report that adhesion and the associated changes in cell shape and cytoskeletal tension are all required for GTP-bound RhoA to activate its downstream effector, ROCK. Using an in vitro kinase assay for endogenous ROCK, we found that cells in suspension, attached on substrates coated with low density fibronectin, or on spreading-restrictive micropatterned islands all exhibited low ROCK activity and correspondingly low myosin light chain phosphorylation, in the face of high levels of GTP-bound RhoA. In contrast, allowing cells to spread against substrates rescued ROCK and myosin activity. Interestingly, inhibition of tension with cytochalasin D or blebbistatin also inhibited ROCK activity within 20 min. The abrogation of ROCK activity by cell detachment or inhibition of tension could not be rescued by constitutively active RhoA-V14. These results suggest the existence of a feedback loop between cytoskeletal tension, adhesion maturation, and ROCK signaling that likely contributes to numerous mechanochemical processes.  相似文献   
39.
The secretome of the pouch skin of the model marsupial the tammar wallaby, Macropus eugenii has been investigated using techniques of two-dimensional gel electrophoresis, in-gel trypsin digestion followed by nanoliquid chromatography coupled tandem mass spectrometry (LC-MS/MS). Differences in the patterns of secreted proteins were observed in the female pouch at three stages of maturity — reproductively immature; reproductively mature and active and mature, postreproductively active. Skin from the underarm area of mature females had a markedly different secreted protein profile. The greatest diversity of proteins was seen in the mature reproductive pouch and from an opportunistic sample collected from the pouch another mature female marsupial, the common wombat, Vombatus ursinus. A total of 20 proteins were confidently identified from the pouch skin secretions of the tammar wallaby and wombats, whilst 20 proteins were tentatively identified. In all skin secretomes, globins were the most abundant proteins whilst the antimicrobial, dermcidin was detected in the wombat sample. Some proteins such as keratin and actin could be sourced to sloughed and degraded skin cells. A number of proteins were present at such low concentrations that confident identification was not possible. This was compounded by the lack of a comprehensive database of marsupial proteins which constrains the reliability of automated identification protocols.  相似文献   
40.
Biological Trace Element Research - This research article aims to establish the intake ratio of probiotic Lactobacillus plantarum 299v with iron supplement pearl millet by central composite design...  相似文献   
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