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排序方式: 共有198条查询结果,搜索用时 15 毫秒
1.
Atanu Sarkar 《EcoHealth》2010,7(1):114-126
Millions of people living in India are at risk by consuming arsenic contaminated groundwater. Several technological solutions
have failed to address the problem due to segmental approaches, resulting in human suffering for a period of three decades.
The article is based on an analysis of arsenic-related health problems from an ecosystem perspective through a primary survey
conducted in five arsenic affected villages in the state of West Bengal and review of existing research and policy documents.
Although modern agricultural practices and drinking water policies have resulted in arsenic contamination of groundwater,
current mitigation policy is essentially confined to biomedical approaches, which includes potable water supply and medical
care. The study also shows that existing disparity, difficulty in coping, inaccessibility to health service and potable water
supply and lack of participation in decision making have resulted in more suffering among the poor. On the other hand, spreading
of arsenic contamination in the ecosystem remains unabated. Foods grown in the affected area have emerged as additional sources
of exposure to humans. There is lack of evidence of any perceivable benefits due to sustainable agriculture, as present nature
of agriculture practice is essentially driven by crop yield only. Further research is needed to generate credible evidence
of alternative agriculture paradigms that may eventually reduce body burden of arsenic through reduced dependency on groundwater. 相似文献
2.
Arjun H. Ananth Natarajan Manikandan Ravi Kumar Rajan Ramakrishnan Elancheran Kunasekaran Lakshmithendral Muthiah Ramanathan Atanu Bhattacharjee Senthamaraikannan Kabilan 《化学与生物多样性》2020,17(2)
Breast Cancer (BCa) is the most often diagnosed cancer among women who were in the late 1940’s. Breast cancer growth is largely dependent on the expression of estrogen and progesterone receptor. Breast cancer cells may have one, both, or none of these receptors. The treatment for breast cancer may involve surgery, hormonal therapy (Tamoxifen, an aromatase inhibitor, etc.) and oral chemotherapeutic drugs. The molecular docking technique reported the findings on the potential binding modes of the 2‐(2‐bromo‐3‐nitrophenyl)‐5‐phenyl‐1,3,4‐oxadiazole derivatives with the estrogen receptor (PDB ID: 3ERT). The 1,3,4‐oxadiazole derivatives 4a – 4j have been synthesized and described by spectroscopic method. 2‐(2‐Bromo‐6‐nitrophenyl)‐5‐(4‐bromophenyl)‐1,3,4‐oxadiazole ( 4c ) was reconfirmed by single‐crystal XRD. All the compounds have been tested in combination with generic Imatinib pharmaceutical drug against breast cancer cell lines isolated from Caucasian woman MCF‐7, MDA‐MB‐453 and MCF‐10A non‐cancer cell lines. The compounds with the methoxy (in 4c ) and methyl (in 4j ) substitution were shown to have significant cytotoxicity, with 4c showing dose‐dependent activation and decreased cell viability. The mechanism of action was reported by induced apoptosis and tested by a DNA enzyme inhibitor experiment (ELISA) for Methyl Transferase. Molecular dynamics simulations were made for hit molecule 4c to study the stability and interaction of the protein?ligand complex. The toxicity properties of ADME were calculated for all the compounds. All these results provide essential information for further clinical trials. 相似文献
3.
Najealicka Armstrong Malaisamy Ramamoorthy Delina Lyon Kimberly Jones Atanu Duttaroy 《PloS one》2013,8(1)
Silver nanoparticles (AgNPs), like almost all nanoparticles, are potentially toxic beyond a certain concentration because the survival of the organism is compromised due to scores of pathophysiological abnormalities past that concentration. However, the mechanism of AgNP toxicity remains undetermined. Instead of applying a toxic dose, we attempted to monitor the effects of AgNPs at a nonlethal concentration on wild type Drosophila melanogaster by exposing them throughout their development. All adult flies raised in AgNP doped food showed that up to 50 mg/L concentration AgNP has no negative influence on median survival; however, these flies appeared uniformly lighter in body color due to the loss of melanin pigments in their cuticle. Additionally, fertility and vertical movement ability were compromised due to AgNP feeding. Determination of the amount of free ionic silver (Ag+) led us to claim that the observed biological effects have resulted from the AgNPs and not from Ag+. Biochemical analysis suggests that the activity of copper dependent enzymes, namely tyrosinase and Cu-Zn superoxide dismutase, are decreased significantly following the consumption of AgNPs, despite the constant level of copper present in the tissue. Consequently, we propose a mechanism whereby consumption of excess AgNPs in association with membrane bound copper transporter proteins cause sequestration of copper, thus creating a condition that resembles copper starvation. This model also explains the cuticular demelanization effect resulting from AgNP since tyrosinase activity is essential for melanin biosynthesis. Finally, we claim that Drosophila, an established genetic model system, can be well utilized for further understanding of the biological effects of nanoparticles. 相似文献
4.
ABSTRACTChemotherapy administration may result in the disruption of circadian rhythms and impairment of quality of life (QoL) of cancer patients. Nevertheless, we have little knowledge on the long-term consequences of chemotherapy and the effects of hospitalization. In the present study, we employed the two-factor repeated-measure cross-sectional design to determine the effects of chemotherapy and hospitalization on rest-activity (RA) rhythm and QoL of breast cancer patients. Initially, we randomly selected 39 inpatients and 42 outpatients, scheduled to receive six cycles of chemotherapy, from the Regional Cancer Center (RCC), Raipur, India. Finally, 30 patients in each group were included in the current study. We monitored circadian RA rhythm and QoL using wrist actigraphy and QLQ-C30 and QLQ-BR23, respectively, during the 1st (C1), 3rd (C3) and 6th (C6) chemotherapy cycles. Results revealed that with the progression of chemotherapy cycles (from C1 to C6), all rhythm parameters, namely mesor, amplitude, acrophase, rhythm quotient (RQ), circadian quotient (CQ), peak activity (PA), dichotomy index and autocorrelation coefficient, significantly decreased in both cancer in- and outpatients. In both groups of patients and during C1–C6, all functional and global QoL measures of QLQ-C30 and QLQ-BR23 significantly decreased and the symptoms significantly increased, except constipation, body image, sexual functioning and future perspectives in outpatients. The hospitalization exacerbated the problems associated with the RA rhythm and the QoL of the patients. In conclusion, the current study highlighted the negative consequences of hospitalization among inpatients, irrespective of the stage of cancer. We, therefore, recommend that cancer patients should be administered with chemotherapy as outpatients. The proposed protocol might have a covert bearing on the expression of better physiological state leading to satisfactory treatment outcomes. 相似文献
5.
BackgroundThe global epidemic of Type-2-Diabetes (T2D) highlights the need for novel therapeutic targets and agents. Roux-en-Y-Gastric-Bypass (RYGB) is the most effective treatment. Studies investigating the mechanisms of RYGB suggest a role for post-operative changes in portal glucose levels. We investigate the impact of stimulating portal glucose sensors on systemic glucose levels in health and T2D, and evaluated the role of sodium-glucose-cotransporter-3 (SGLT3) as the possible sensor.MethodsSystemic glucose and hormone responses to portal stimulation were measured. In Sprague-Dawley (SD) rats, post-prandial state was simulated by infusing glucose into the portal vein. The SGLT3 agonist, alpha-methyl-glucopyranoside (αMG), was then added to further stimulate the portal sensor. To elucidate the neural pathway, vagotomy or portal denervation was followed by αMG+glucose co-infusion. The therapeutic potential of portal glucose sensor stimulation was investigated by αMG-only infusion (vs. saline) in SD and Zucker-Diabetic-Fatty (ZDF) rats. Hepatic mRNA expression was also measured.ResultsαMG+glucose co-infusion reduced peak systemic glucose (vs. glucose alone), and lowered hepatic G6Pase expression. Portal denervation, but not vagotomy, abolished this effect. αMG-only infusion lowered systemic glucose levels. This glucose-lowering effect was more pronounced in ZDF rats, where portal αMG infusion increased insulin, C-peptide and GIP levels compared to saline infusions.ConclusionsThe portal vein is capable of sensing its glucose levels, and responds by altering hepatic glucose handling. The enhanced effect in T2D, mediated through increased GIP and insulin, highlights a therapeutic target that could be amenable to pharmacological modulation or minimally-invasive surgery. 相似文献
6.
The synthesis of small-sized quantum dots (QDs) (1–10 nm) via the green route has garnered great interest regarding their prospective use in many biological applications (diagnosis, drug delivery and in vivo sensing); this is difficult to achieve using chemical synthesis methods, which produce larger size QD particles and also require hazardous reagents. Here, we synthesized biogenic cadmium sulphide (CdS) QDs using green tea extract as the reducing agent to produce particles that were homogeneous and a smaller size of 2–4 nm. We also elucidated the (a) protein binding, (b) antibacterial use and (c) sensing applications of biogenic CdS QDs in this present work. The biosynthesized CdS QDs were found to have extensive antibacterial activity against both Gram-negative Escherichia coli and Gram-positive Enterococcus faecalis bacterial strains. The introduction of QDs in biological medium can lead to the formation of protein–QD complexes; therefore we investigated the binding interaction of CdS QDs with the carrier protein human serum albumin (HSA) in vitro. The synthesized CdS QDs quenched the intrinsic fluorescence of HSA through a static quenching mechanism and the binding constant (Kb) was in the order of 104 M−1. It was also observed that the presence of biogenic CdS QDs affected the HSA–ligand interactions in vitro. The synthesized CdS made highly effective sensors for tetracycline, rifampicin, and bilirubin with limit of detection (LOD) values of 99, 141 and 29 ng/ml, respectively. 相似文献
7.
Babichuk Nicole Sarkar Atanu Mulay Shree Knight John Bautista Joseph James Young Cora J. 《EcoHealth》2022,19(1):99-113
EcoHealth - Presence of PBDEs tested in 127 liver samples from Atlantic Cod (Gadus morhua) and Turbot (Scophthalmus Maximus) and 80 adult participants from two rural Newfoundland communities.... 相似文献
8.
Das Aparimita Ganesan Harsha Sriramulu Sushmitha Marotta Francesco Kanna N. R. Rajesh Banerjee Antara He Fang Duttaroy Asim K. Pathak Surajit 《Molecular and cellular biochemistry》2021,476(11):4117-4131
Molecular and Cellular Biochemistry - Oxidative stress has been known to be the underlying cause in many instances of cancer development. The new aspect of cancer genesis that has caught the... 相似文献
9.
The specificity of protein–nucleic acid recognition is believed to originate largely from hydrogen bonding between protein polar atoms, primarily side-chain and polar atoms of nucleic acid bases. One way to design new nucleic acid binding proteins of novel specificity is by structure-guided alterations of the hydrogen bonding patterns of a nucleic acid–protein complex. We have used cI repressor of bacteriophage λ as a model system. In the λ-repressor–DNA complex, the -NH2 group (hydrogen bond donor) of lysine-4 of λ-repressor forms hydrogen bonds with the amide carbonyl atom of asparagine-55 (acceptor) and the O6 (acceptor) of CG6 of operator site OL1. Substitution of lysine-4 (two donors) by iso-steric S-(2-hydroxyethyl)-cysteine (one donor and one acceptor), by site-directed mutagenesis and chemical modification, leads to switch of binding specificity of λ-repressor from C:G to T:A at position 6 of OL1. This suggests that unnatural amino acid substitutions could be a simple way of generating nucleic acid binding proteins of altered specificity. 相似文献
10.
Twenty four shift workers (8 from a steel industry and 16 from a Government hospital) participated in the study. The subjects
were instructed to self-measure oral temperature, 4 6 times a day for about three weeks. Sleep quantity and quality for each
subject were analysed with the help of an appropriate inventory. The data were analysed by cosinor and power spectrum methods.
The frequency of circadian rhythm detection was in the order of 48% in senior nurses, 29% in steel plant workers and 14% in
junior nurses. These were also complemented by the results of power spectrum analysis. Present results suggest that rhythms
of subjective fatigue and subjective drowsiness are governed neither by oral temperature oscillator nor by the sleep/wake
cycle oscillator. The results show that shift rotation pattern chiefly modulates the circadian time structure of shift workers.
It is also suggested that the phenomenon of circadian rhythm desynchronization in oral temperature appears to be independent
of per day total sleep length. 相似文献