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341.
342.
Wu J van Geen A Ahmed KM Alam YA Culligan PJ Escamilla V Feighery J Ferguson AS Knappett P Mailloux BJ McKay LD Serre ML Streatfield PK Yunus M Emch M 《PloS one》2011,6(12):e29593
Background
Millions of households throughout Bangladesh have been exposed to high levels of arsenic (As) causing various deadly diseases by drinking groundwater from shallow tubewells for the past 30 years. Well testing has been the most effective form of mitigation because it has induced massive switching from tubewells that are high (>50 µg/L) in As to neighboring wells that are low in As. A recent study has shown, however, that shallow low-As wells are more likely to be contaminated with the fecal indicator E. coli than shallow high-As wells, suggesting that well switching might lead to an increase in diarrheal disease.Methods
Approximately 60,000 episodes of childhood diarrhea were collected monthly by community health workers between 2000 and 2006 in 142 villages of Matlab, Bangladesh. In this cross-sectional study, associations between childhood diarrhea and As levels in tubewell water were evaluated using logistic regression models.Results
Adjusting for wealth, population density, and flood control by multivariate logistic regression, the model indicates an 11% (95% confidence intervals (CIs) of 4–19%) increase in the likelihood of diarrhea in children drinking from shallow wells with 10–50 µg/L As compared to shallow wells with >50 µg/L As. The same model indicates a 26% (95%CI: 9–42%) increase in diarrhea for children drinking from shallow wells with ≤10 µg/L As compared to shallow wells with >50 µg/L As.Conclusion
Children drinking water from shallow low As wells had a higher prevalence of diarrhea than children drinking water from high As wells. This suggests that the health benefits of reducing As exposure may to some extent be countered by an increase in childhood diarrhea. 相似文献343.
Julhash U. Kazi Jianmin Sun Bengt Phung Fahad Zadjali Amilcar Flores-Morales Lars R?nnstrand 《The Journal of biological chemistry》2012,287(43):36509-36517
The receptor tyrosine kinase Flt3 is an important growth factor receptor in hematopoiesis, and gain-of-function mutations of the receptor contribute to the transformation of acute myeloid leukemia. SOCS6 (suppressor of cytokine signaling 6) is a member of the SOCS family of E3 ubiquitin ligases that can regulate receptor tyrosine kinase signal transduction. In this study, we analyzed the role of SOCS6 in Flt3 signal transduction. The results show that ligand stimulation of Flt3 can induce association of SOCS6 and Flt3 and tyrosine phosphorylation of SOCS6. Phosphopeptide fishing indicated that SOCS6 binds directly to phosphotyrosines 591 and 919 of Flt3. By using stably transfected Ba/F3 cells with Flt3 and/or SOCS6, we show that the presence of SOCS6 can enhance ubiquitination of Flt3, as well as internalization and degradation of the receptor. The presence of SOCS6 also induces weaker activation of Erk1/2, but not Akt, in transfected Ba/F3 and UT-7 cells and in OCI-AML-5 cells. The absence of SOCS6 promotes Ba/F3 and UT-7 cell proliferation induced by oncogenic internal tandem duplications of Flt3. Taken together, these results suggest that SOCS6 negatively regulates Flt3 activation, the downstream Erk signaling pathway, and cell proliferation. 相似文献
344.
Delayed recovery of skeletal muscle mass following hindlimb immobilization in mTOR heterozygous mice
The present study addressed the hypothesis that reducing mTOR, as seen in mTOR heterozygous (+/-) mice, would exaggerate the changes in protein synthesis and degradation observed during hindlimb immobilization as well as impair normal muscle regrowth during the recovery period. Atrophy was produced by unilateral hindlimb immobilization and data compared to the contralateral gastrocnemius. In wild-type (WT) mice, the gradual loss of muscle mass plateaued by day 7. This response was associated with a reduction in basal protein synthesis and development of leucine resistance. Proteasome activity was consistently elevated, but atrogin-1 and MuRF1 mRNAs were only transiently increased returning to basal values by day 7. When assessed 7 days after immobilization, the decreased muscle mass and protein synthesis and increased proteasome activity did not differ between WT and mTOR(+/-) mice. Moreover, the muscle inflammatory cytokine response did not differ between groups. After 10 days of recovery, WT mice showed no decrement in muscle mass, and this accretion resulted from a sustained increase in protein synthesis and a normalization of proteasome activity. In contrast, mTOR(+/-) mice failed to fully replete muscle mass at this time, a defect caused by the lack of a compensatory increase in protein synthesis. The delayed muscle regrowth of the previously immobilized muscle in the mTOR(+/-) mice was associated with a decreased raptor?4EBP1 and increased raptor?Deptor binding. Slowed regrowth was also associated with a sustained inflammatory response (e.g., increased TNFα and CD45 mRNA) during the recovery period and a failure of IGF-I to increase as in WT mice. These data suggest mTOR is relatively more important in regulating the accretion of muscle mass during recovery than the loss of muscle during the atrophy phase, and that protein synthesis is more sensitive than degradation to the reduction in mTOR during muscle regrowth. 相似文献
345.
Tanusree Sen Nilkantha Sen Maartje G. Noordhuis Rajani Ravi T-C Wu Patrick K. Ha David Sidransky Mohammad Obaidul Hoque 《PloS one》2012,7(11)
Oxoglutarate dehydrogenase (OGDH) is the first and rate-limiting component of the multi-enzyme OGDH complex (OGDHC) whose malfunction is associated with neuro-degeneration. The essential role of this complex is in the degradation of glucose and glutamate and the OGDHL gene (one component of OGDHC) is down-regulated by promoter hypermethylation in many different cancer types. These properties suggest a potential growth modulating role of OGDHL in cancer; however, the molecular mechanism through which OGDHL exerts its growth modulating function has not been elucidated.Here, we report that restoration of OGDHL expression in cervical cancer cells lacking endogenous OGDHL expression suppressed cell proliferation, invasion and soft agar colony formation in vitro. Knockdown of OGDHL expression in cervical cancer cells expressing endogenous OGDHL had the opposite effect. Forced expression of OGDHL increased the production of reactive oxygen species (ROS) leading to apoptosis through caspase 3 mediated down-regulation of the AKT signaling cascade and decreased NF-κB phosphorylation. Conversely, silencing OGDHL stimulated the signaling pathway via increased AKT phosphorylation. Moreover, the addition of caspase 3 or ROS inhibitors in the presence of OGDHL increased AKT signaling and cervical cancer cell proliferation.Taken together, these data suggest that inactivation of OGDHL can contribute to cervical tumorigenesis via activation of the AKT signaling pathway and thus support it as an important anti-proliferative gene in cervical cancer. 相似文献
346.
Mohammad R. Hoque Xavier Gabarrell i Durany Cristina Sendra i Sala Gara Villalba Méndez Laura Talens Peiró Teresa Vicent Huguet 《Journal of Industrial Ecology》2012,16(5):699-709
We used a thermodynamic framework to characterize the resource consumption of the construction sector in 2001 in Catalonia, the northeast region of Spain. The analysis was done with a cradle‐to‐product life cycle approach using material flow analysis (MFA) and exergy accounting methodologies to quantify the total material and energy inputs in the sector. The aim was to identify the limitations of resource metabolism in the sector and to pinpoint the opportunities for improved material selection criteria, processing, reuse, and recycling for sustainable resource use. The results obtained from MFA showed that nonrenewables such as minerals and natural rocks, cement and derivatives, ceramics, glass, metals, plastics, paints and other chemicals, electric and lighting products, and bituminous mix products accounted for more than 98% of the input materials in the construction sector. The exergy analysis quantified a total 113.1 petajoules (PJ) of exergy inputs in the sector; utilities accounted for 57% of this exergy. Besides exergy inputs, a total of 6.85 million metric tons of construction and demolition waste was generated in 2001. With a recycling rate of 6.5%, the sector recovered 1.3 PJ of exergy. If the sector were able to recycle 80% of construction and demolition waste, then exergy recovery would be 10.3 PJ. Hence the results of this analysis indicate that improvements are required in manufacturing processes and recycling activities, especially of energy‐intensive materials, in order to reduce the inputs of utilities and the extraction of primary materials from the environment. 相似文献
347.
Hoque R Sohail MA Salhanick S Malik AF Ghani A Robson SC Mehal WZ 《American journal of physiology. Gastrointestinal and liver physiology》2012,302(10):G1171-G1179
Inflammation contributes to liver injury in acetaminophen (APAP) hepatotoxicity in mice and is triggered by stimulation of immune cells. The purinergic receptor P2X7 is upstream of the nod-like receptor family, pryin domain containing-3 (NLRP3) inflammasome in immune cells and is activated by ATP and NAD that serve as damage-associated molecular patterns. APAP hepatotoxicity was assessed in mice genetically deficient in P2X7, the key inflammatory receptor for nucleotides (P2X7-/-), and in wild-type mice. P2X7-/- mice had significantly decreased APAP-induced liver necrosis. In addition, APAP-poisoned mice were treated with the specific P2X7 antagonist A438079 or etheno-NAD, a competitive antagonist of NAD. Pre- or posttreatment with A438079 significantly decreased APAP-induced necrosis and hemorrhage in APAP liver injury in wild-type but not P2X7-/- mice. Pretreatment with etheno-NAD also significantly decreased APAP-induced necrosis and hemorrhage in APAP liver injury. In addition, APAP toxicity in mice lacking the plasma membrane ecto-NTPDase CD39 (CD39-/-) that metabolizes ATP was examined in parallel with the use of soluble apyrase to deplete extracellular ATP in wild-type mice. CD39-/- mice had increased APAP-induced hemorrhage and mortality, whereas apyrase also decreased APAP-induced mortality. Kupffer cells were treated with extracellular ATP to assess P2X7-dependent inflammasome activation. P2X7 was required for ATP-stimulated IL-1β release. In conclusion, P2X7 and exposure to the ligands ATP and NAD are required for manifestations of APAP-induced hepatotoxicity. 相似文献
348.
Badrul Haque Kazi Mohibur Rahman Azharul Hoque ATM Hasibul Hasan Rajib Nayan Chowdhury Sharif Uddin Khan Mondal Badrul Alam Mansur Habib Quazi Deen Mohammad 《BMC neurology》2012,12(1):1-4
Background
The correlation between intracranial pressure (ICP) and intraocular pressure (IOP) is still controversial in literature and hence whether IOP can be used as a non-invasive surrogate of ICP remains unknown. The aim of the current study was to further clarify the potential correlation between ICP and IOP.Methods
The IOP measured with Goldmann applanation tonometer was carried out on 130 patients whose ICP was determined via lumber puncture. The Pearson correlation coefficient between ICP and IOP was calculated, the fisher line discriminated analysis to evaluate the effectivity of using IOP to predict the ICP level.Results
A significant correlation between ICP and IOP was found. ICP was correlated significantly with IOP of the right eyes (p?<?0.001) and IOP of the left eyes (p?=?0.001) and mean IOP of both eyes (p?<?0.001), respectively. However, using IOP as a measurement to predict ICP, the accuracy rate was found to be 65.4%.Conclusion
Our data suggested that although a significant correlation exists between ICP and IOP, caution needs to be taken when using IOP readings by Goldmann applanation tonometer as a surrogate for direct cerebrospinal fluid pressure measurement of ICP. 相似文献349.
350.
Sayem Ahmed Mohammad Enamul Hoque Abdur Razzaque Sarker Marufa Sultana Ziaul Islam Rukhsana Gazi Jahangir A. M. Khan 《PloS one》2016,11(2)