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81.

Background

Chronic stimulant abuse is associated with both impairment in decision making and structural abnormalities in brain gray and white matter. Recent data suggest these structural abnormalities may be related to functional impairment in important behavioral processes.

Methodology/Principal Findings

In 15 cocaine-dependent and 18 control subjects, we examined relationships between decision-making performance on the Iowa Gambling Task (IGT) and white matter integrity as measured by diffusion tensor imaging (DTI). Whole brain voxelwise analyses showed that, relative to controls, the cocaine group had lower fractional anisotropy (FA) and higher mean of the second and third eigenvalues (λ⊥) in frontal and parietal white matter regions and the corpus callosum. Cocaine subjects showed worse performance on the IGT, notably over the last 40 trials. Importantly, FA and λ⊥ values in these regions showed a significant relationship with IGT performance on the last 40 trials.

Conclusions

Compromised white matter integrity in cocaine dependence may be related to functional impairments in decision making.  相似文献   
82.
To investigate the effect of exogenously applied 28-homobrassinolide (HBL) on drought-stressed plants, photosynthesis and antioxidant systems were examined in Indian mustard (Brassica juncea L.). Seedlings of Indian mustard were subjected to drought stress for 7 days at the 8–14 (DS1)/15–21 (DS2) days’ stage of growth and then returned to normal conditions of growth. These seedlings were sprayed with HBL (0.01 μM) at the 30-day stage and were sampled at 60 days to assess the changes in growth, photosynthesis and antioxidant enzymes. Plants exposed to stress at either of the stages of growth exhibited a significant decrease in growth and photosynthesis. The exposure of plants to stress at an earlier stage (DS1) was more inhibitory than that at a later stage (DS2). However, the follow-up treatment with HBL significantly improved the values of these parameters and also overcame the inhibitory effect of water stress. The activity of antioxidant enzymes [catalase (E.C. 1.11.1.6), peroxidase (E.C. 1.11.1.7) and superoxide dismutase (E.C. 1.15.1.1)] and proline content in leaves exhibited an increase in response to both the treatment factors, where their interaction had an additive effect. It was, therefore, concluded that the elevated antioxidant system, at least in part, was responsible for amelioration of the drought stress.  相似文献   
83.
Quaternary amine of diethylaminoethyl rosin ester (QRMAE), chemically synthesized biocompatible rosin based cationic surfactant, has various biological applications including its use as a food product additive. In this study, we examined the amorphous aggregation behavior of mammalian serum albumins at pH 7.5, i.e., two units above their isoelectric points (pI ~5.5), and the roles played by positive charge and hydrophobicity of exogenously added rosin surfactant QRMAE. The study was carried out on five mammalian serum albumins, using various spectroscopic methods, dye binding assay, circular dichroism and electron microscopy. The thermodynamics of the binding of mammalian serum albumins to cationic rosin modified surfactant were established using isothermal titration calorimetry (ITC). It was observed that a suitable molar ratio of protein to QRMAE surfactant enthusiastically induces amorphous aggregate formation at a pH above two units of pI. Rosin surfactant QRMAE-albumins interactions revealed a unique interplay between the initial electrostatic and the subsequent hydrophobic interactions that play an important role towards the formation of hydrophobic interactions-driven amorphous aggregate. Amorphous aggregation of proteins is associated with varying diseases, from the formation of protein wine haze to the expansion of the eye lenses in cataract, during the expression and purification of recombinant proteins. This study can be used for the design of novel biomolecules or drugs with the ability to neutralize factor(s) responsible for the aggregate formation, in addition to various other industrial applications.  相似文献   
84.
Staphylococcus aureus causes life-threatening pneumonia in hospitals and deadly superinfection during viral influenza. The current study investigated the role of surfactant protein A (SP-A) in opsonization and clearance of S. aureus. Previous studies showed that SP-A mediates phagocytosis via the SP-A receptor 210 (SP-R210). Here, we show that SP-R210 mediates binding and control of SP-A-opsonized S. aureus by macrophages. We determined that SP-A binds S. aureus through the extracellular adhesin Eap. Consequently, SP-A enhanced macrophage uptake of Eap-expressing (Eap(+)) but not Eap-deficient (Eap(-)) S. aureus. In a reciprocal fashion, SP-A failed to enhance uptake of Eap(+) S. aureus in peritoneal Raw264.7 macrophages with a dominant negative mutation (SP-R210(DN)) blocking surface expression of SP-R210. Accordingly, WT mice cleared infection with Eap(+) but succumbed to sublethal infection with Eap- S. aureus. However, SP-R210(DN) cells compensated by increasing non-opsonic phagocytosis of Eap(+) S. aureus via the scavenger receptor scavenger receptor class A (SR-A), while non-opsonic uptake of Eap(-) S. aureus was impaired. Macrophages express two isoforms: SP-R210(L) and SP-R210(S). The results show that WT alveolar macrophages are distinguished by expression of SP-R210(L), whereas SR-A(-/-) alveolar macrophages are deficient in SP-R210(L) expressing only SP-R210(S). Accordingly, SR-A(-/-) mice were highly susceptible to both Eap(+) and Eap(-) S. aureus. The lungs of susceptible mice generated abnormal inflammatory responses that were associated with impaired killing and persistence of S. aureus infection in the lung. In conclusion, alveolar macrophage SP-R210(L) mediates recognition and killing of SP-A-opsonized S. aureus in vivo, coordinating inflammatory responses and resolution of S. aureus pneumonia through interaction with SR-A.  相似文献   
85.
Three experiments were carried out to determine whether dietary wood (oak) charcoal applied during entire or phase feeding period would affect growth performance, abdominal fat weight, carcass weight, carcass yield, carcass composition and nutrient excretion of broilers and to determine whether dietary wood charcoal supplementation would affect laying performance and egg quality of laying hens. In the first experiment, different inclusion levels (0, 25, 50 and 100 g/kg feed) of wood charcoal in the diet were examined for a 6-week-period using broiler chicks of initial age 1 week. Dietary wood charcoal significantly increased feed intake (P<0.001), body weight gain (P<0.001) and improved feed conversion ratio (P<0.05) up to 28 days of age. However, at 49 days of age, charcoal inclusion did not significantly (P>0.05) affect body weight gain, feed intake, carcass weight and carcass yield, but increased (P<0.05) feed conversion ratio, carcass ash content, fat excretion, while reducing (P<0.05) mineral excretion in a dose dependent manner. In the second experiment, a phase application of dietary wood charcoal for a 6-week-period broiler chicks of initial age 1 week was assessed. During the first 28 days of age wood charcoal improved feed conversion ratio significantly (P<0.05). At 49 days of age, the groups receiving charcoal in the starter and/or finisher diets showed significantly (P<0.05) higher body weight gain and carcass weight than the control group receiving no charcoal. In the third experiment, different levels (0, 10, 20 and 40 g/kg feed) of wood charcoal supplementation to a layer diet were examined for a 7-week-period using laying hens of initial age 34 weeks. Dietary charcoal supplementation did not have a significant effect on any parameters related to performance and egg quality, but significantly reduced number of cracked eggs and the reduction was dose dependent (P<0.01). These data demonstrate that wood charcoal inclusion to the diet could be of value in improving broiler performance during the first 28 days of fattening period. In later ages, the positive effects of wood charcoal are limited. However, in laying hens dietary supplementation of wood charcoal reduces number of cracked eggs.  相似文献   
86.
BackgroundHigh salt consumption is an important risk factor of elevated blood pressure. In Bangladesh about 20 million people are at high risk of hypertension due to climate change induced saline intrusion in water. The objective of this study is to assess beliefs, perceptions, and practices associated with salt consumption in coastal Bangladesh.MethodsThe study was conducted in Chakaria, Bangladesh between April-June 2011. It was a cross sectional mixed method study. For the qualitative study 6 focus group discussions, 8 key informant interviews, 60 free listing exercises, 20 ranking exercises and 10 observations were conducted. 400 adults were randomly selected for quantitative survey. For analysis we used SPSS for quantitative data, and Anthropac and Nvivo for qualitative data.ResultsSalt was described as an essential component of food with strong cultural and religious roots. People described both health benefits and risks related to salt intake. The overall risk perception regarding excessive salt consumption was low and respondents believed that the cooking process can render the salt harmless. Respondents were aware that salt is added in many foods even if they do not taste salty but did not recognize that salt can occur naturally in both foods and water.ConclusionsIn the study community people had low awareness of the risks associated with excess salt consumption and salt reduction strategies were not high in their agenda. The easy access to and low cost of salt as well as unrecognised presence of salt in drinking water has created an environment conducive to excess salt consumption. It is important to design general messages related to salt reduction and test tailored strategies especially for those at high risk of hypertension.  相似文献   
87.

Background

Post-discharge mortality among children with severe illness in resource-limited settings is under-recognized and there are limited data. We evaluated post-discharge mortality in a recently reported cohort of children with severe malnutrition and pneumonia, and identified characteristics associated with an increased risk of death.

Methods

Young children (<5 years of age) with severe malnutrition (WHO criteria) and radiographic pneumonia on admission to Dhaka Hospital of icddr,b over a 15-month period were managed according to standard protocols. Those discharged were followed-up and survival status at 12 weeks post-discharge was determined. Verbal autopsy was requested from families of those that died.

Results

Of 405 children hospitalized with severe malnutrition and pneumonia, 369 (median age, 10 months) were discharged alive with a follow-up plan. Of these, 32 (8.7%) died in the community within 3 months of discharge: median 22 (IQR 9–35) days from discharge to death. Most deaths were reportedly associated with acute onset of new respiratory or gastrointestinal symptoms. Those that died following discharge were significantly younger (median 6 [IQR 3,12] months) and more severely malnourished, on admission and on discharge, than those that survived. Bivariate analysis found that severe wasting on admission (OR 3.64, 95% CI 1.66–7.97) and age <12 months (OR 2.54, 95% CI 1.1–8.8) were significantly associated with post-discharge death. Of those that died in the community, none had attended a scheduled follow-up and care-seeking from a traditional healer was more common (p<0.001) compared to those who survived.

Conclusion and Significance

Post-discharge mortality was common in Bangladeshi children following inpatient care for severe malnutrition and pneumonia. The underlying contributing factors require a better understanding to inform the potential of interventions that could improve survival.  相似文献   
88.
Summary This study investigates the effects of anticancer drugs and immunomodulating agents on the release of interleukin-6 (IL-6) from lipopolysaccharide-stimulated human peripheral blood mononuclear leucocytes in vitro. The addition of non-cytotoxic concentrations of Adriamycin (doxorubicin), vincristine and 4-OOH-cyclophosphamide (the in vitro active analogue of cyclophosphamide) resulted in suppression of IL-6 release. The drugs bleomycin, FK156 [d-lactoyl-l-alanyl--d-glutamyl-(l)-meso-diaminopimelyl-(l)-glycine], FK565 [heptanoyl--d-glutamyl-(l)-meso-diaminopimelyl-(d)-alanine] and the immunosuppressive agent cyclosporin A did not alter the release of IL-6 in the same experimental system.  相似文献   
89.
Chemotherapy has been used widely to treat cancer, both as a systemic therapy and as a local treatment. Unfortunately, many types of cancer are still refractory to chemotherapy. The mechanisms of anticancer drug resistance have been extensively explored but have not been fully characterized. This study analyzed the occurrences of polymorphism (SNP) in the MDR1 gene in breast cancer patients and determined a possible association with chemotherapy. The study group included one hundred breast carcinoma patients who subsequently received chemotherapy (the regimen generally consisted of commonly used drugs such as cyclophosphamide, adriamycin, 5-fluorouracil, docetaxel and their combinations). Blood samples from 100 healthy individuals are used, as controls were also genotyped for the MDR1 gene. This investigation revealed a significant correlation with response to various regimens of chemotherapy showing a low response to therapy with the CT/TT genotype at (exon 12) 1236 codon (p < 0.001). These findings demonstrate, for the first time, that the polymorphisms in (exon 12) 1236 codon of the MDR1 gene greatly influence the drug response in patients from the Arab population of Saudi Arabia.  相似文献   
90.
In the present study, the changes that occur in rat liver tissue as a result of the use of grape seed extract (GSE) and low level laser therapy (LLLT) in intraoral wound (IW) healing are analyzed using biochemical parameters. Diode laser application groups received 8 J/cm2 dose LLLT once a day for 4 days (810 nm wavelength, continuous mode, 0.25 W, 9 s). As a result of the biological parameter analysis, it was determined that the oxidative damage caused by the IWs and recovery period on 7th and 14th days could be substantially removed with GSE applications that have antioxidant capacity especially in rat liver tissue. In addition, the active compound of grape seed, catechin is studied in the active site of glycogen synthase kinase 3 (GSK3) target using molecular modeling approaches. Post-processing molecular dynamics (MD) results for catechin is compared with a standard GSK3 inhibitor. MD simulations assisted for better understanding of inhibition mechanism and the crucial amino acids contributing in the ligand binding. These results along with a through free energy analysis of ligands using sophisticated simulations methods are quite striking and it suggests a greater future role for simulation in deciphering complex patterns of molecular mechanism in combination with methods for understanding drug-receptor interactions.  相似文献   
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