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1.

Textile dyes are becoming a growing threat to the environment. This report presents the findings of the study on the toxicity of the textile dye Alizarin Red S on two freshwater microalgae. The acute toxicity assay revealed that 96-h EC50 values of Chlorella vulgaris and Spirulina platensis were 29.81 mg/L and 18.94 mg/L respectively. The pigments chlorophyll-a, b and carotenoids in C. vulgaris on 96-h exposure to the dye were 2.91, 3.29 and 3.01 times lower in analogy to control whereas Spirulina platensis showed 2.89and 2.56 fold decrease in chlorophyll-a and carotenoid content than control. After the test period of 96-h with dye, the protein content of C. vulgaris and S. platensis were 2.33 and 1.77 times lower compared to the control. The growth inhibition rate, pigment as well as the protein content declined in compliance with the rise in dye concentration, which anticipate paradigm about the toxic effects of the textile dye.

  相似文献   
2.
The study was conducted to evaluate the effect of higher temperature beyond optimum range on acute toxicity for malathion (effective concentration 50 %) in Pangasianodon hypophthalmus. A 2 days renewal bioassay system for 96 h was used to determine LC50 value of malathion at three different regimes of temperature that is 30, 32 and 34 °C considering as T1, T2 and T3, respectively. The physico-chemical parameters of water of different treatment groups were estimated during pre and post-exposure of test chemical, following standard methods. The result of short term acute toxicity test at 96 h LC50 values through probit analysis was found to be 7.76, 6.45 and 4.46 µL L?1 for T1, T2, and T3, respectively. The 96 h LC50 of malathion at 34 °C was found to be significantly (p < 0.01) lower as compared with estimated LC50 for malathion at 30 and 32 °C. High temperature and free carbon dioxide coupled with low dissolved oxygen were significantly noticed in T3 group when compared to T1 and T2 groups. Lower LC50 of malathion at 34 °C as compared to 30 and 32 °C showed that at a higher temperature, the toxicity of malathion increased, signifying diminished fish protective response to malathion toxicity. The current study reflects the impact of increased temperature on pesticide toxicity in the aquatic ecosystem, alarming the aqua farmers to judiciously use malathion in ponds.  相似文献   
3.

Background:

Aluminum phosphide (ALP) (celphos) is an agricultural pesticide commonly implicated in poisoning. Literature pertaining to the clinical manifestations and treatment outcome of its poisoning among children is limited.

Materials and Methods:

A retrospective chart review was conducted of the medical records of 30 children aged less than 14 years admitted to pediatric intensive care unit (PICU) of a tertiary care hospital in northern India. Demographic, clinical, and laboratory parameters were recorded. The outcome was categorized into “survivors” and “nonsurvivors.”

Results:

The Mean (SD) age of the enrolled children [19 males (63.3%)] was 8.55 (3.07) years. Among the 30 children, 14 (46.67%) were nonsurvivors and the rest 16 (53.33%) were survivors. Nonsurvivors had ingested significantly higher doses of ALP (P < 0.001), and showed higher time lag to PICU transfer (P 0.031), presence of abnormal radiological findings on chest skiagram (P = 0.007), and a higher Pediatric Risk of Mortality (PRISM) III score (P < 0.001) at admission. Use of magnesium sulfate was associated significantly with survival [odds ratio (OR) (95% CI): 0.11 (0.02-0.66); P 0.016].

Conclusion:

The present study highlights that survival among children with ALP poisoning is predicted by dose of ALP ingestion, time lag to medical attention, and higher PRISM score at admission. Use of magnesium sulfate could be associated with better survival among them.  相似文献   
4.

Objective

To determine the sociodemographic and clinical factors leading to stress among parents whose children are admitted in pediatric intensive care unit (PICU).

Methods

A prospective observational study was conducted in PICU of a tertiary care hospital of north India. Parents of children admitted to PICU for at least 48 h duration were eligible for participation. At the end of 48 h, parental stress was assessed using parental stress scale (PSS:PICU) questionnaire which was administered to the parents. Baseline demographic and clinical parameters of children admitted to PICU were recorded. The parental stress was compared with demographic and clinical characteristics of children using appropriate statistical methods.

Results

A total of 49 parents were finally eligible for participation. Mean (SD) parental stress scores was highest in domains of procedures [1.52 (0.66)] and behavior and emotional [1.32 (0.42)] subscales. Mean (SD) total parental stress score among intubated children [1.31 (0.25)] was significantly more than among non intubated children [0.97 (0.26)] (p?p?=?0.15) and socioeconomic status (p?=?0.32). On subscale analysis, it was found that professional communication is a significant stressor in age groups 0–12 mo [0.61(0.41)] (p?=?0.02). It was observed that parents of intubated children were significantly stressed by the physical appearance of their children (p?p?=?0.008) and impairment in parental role (p?=?0.002). Total parental stress score had a positive correlation with PRISM score (r?=?0.308).

Conclusions

Indian parents are stressed maximally with environment of PICU. Factor leading to parental stress was intubation status of the child and was not affected by gender or socio demographic profile of the parents.  相似文献   
5.
Nanomaterials have recently gained significant interest as they are believed to offer an outstanding prospect for use in environmental remediation. Among many possible candidates, due to their useful properties including magnetic nature, wide surface area, and high absorptivity, ferrite materials hold tremendous appeal, allowing them to be used for multifaceted applications. In the present study, using a sol–gel auto combustion process, a magnetically separable Zn1−xCo0.5xMg0.5xFe2O4 (x = 0.0, 0.25, 0.50, 0.75, 1.0) ferrite with superior photocatalytic activity for dye degradation was manufactured. Rietveld refinement and FTIR studies confirm that a single-phase cubic spinel system was built for all samples with crystallite sizes of 34–57 nm. VSM has determined the magnetic properties of the samples at room temperature. With the introduction of Mg2+ and Co2+ in the Zn ferrites, a transformation from the soft superparamagnetic activity to the hard ferromagnetic character was reported. Considering the band structure in the visible region, the photocatalytic activities of the Zn1−xCo0.5xMg0.5xFe2O4 ferrites for the degradation of the MB dye under natural sunlight were investigated. Zn0.25Co0.375Mg0.375Fe2O4 showed an efficiency of degradation of 99.23% for MB dye with a quick 40 min irradiation period with high reusability of up to four cycles.

Nanomaterials have recently gained significant interest as they are believed to offer an outstanding prospect for use in environmental remediation.  相似文献   
6.
The Sturge Weber syndrome is characterized by developmental delay, seizures in infancy, unilateral cutaneous lesions with ipsilateral leptomeningeal enhancement. We report an unusual presentation of Sturge Weber syndrome with bilateral port wine nevus on the trunk and face along with bilateral cortical involvement in a developmentally normal child with progressive megalencephaly.  相似文献   
7.
8.
Pot culture experiments were performed under controlled greenhouse conditions to investigate whether four Cr(VI)-reducing bacterial strains (SUCR44, SUCR140, SUCR186, and SUCR188) were able to decrease Cr toxicity to Pisum sativum plants in artificially Cr(VI)-contaminated soil. The effect of pretreatment of soil with chromate-reducing bacteria on plant growth, chromate uptake, bioaccumulation, nodulation, and population of Rhizobium was found to be directly influenced by the time interval between bacterial treatment and seed sowing. Pretreatment of soil with SUCR140 (Microbacterium sp.) 15 days before sowing (T+15) showed a maximum increase in growth and biomass in terms of root length (93 %), plant height (94 %), dry root biomass (99 %), and dry shoot biomass (99 %). Coinoculation of Rhizobium with SUCR140 further improved the aforementioned parameter. Compared with the control, coinoculation of SUCR140+R showed a 117, 116, 136, and 128 % increase, respectively, in root length, plant height, dry root biomass, and dry shoot biomass. The bioavailability of Cr(VI) decreased significantly in soil (61 %) and in uptake (36 %) in SUCR140-treated plants; the effects of Rhizobium, however, either alone or in the presence of SUCR140, were not significant. The populations of Rhizobium (126 %) in soil and nodulation (146 %) in P. sativum improved in the presence of SUCR140 resulting in greater nitrogen (54 %) concentration in the plants. This study shows the usefulness of efficient Cr(VI)-reducing bacterial strain SUCR140 in improving yields probably through decreased Cr toxicity and improved symbiotic relationship of the plants with Rhizobium. Further decrease in the translocation of Cr(VI) through improved nodulation by Rhizobium in the presence of efficient Cr-reducing bacterial strains could also decrease the accumulation of Cr in shoots.  相似文献   
9.
OBJECTIVE: The purpose of this study was to evaluate the efficacy of radiotherapy and concurrent mitomycin-C (MC) plus 5-fluorouracil (5FU) infusion in locally advanced squamous cell carcinoma of the head and neck (SCCHN). METHODS: Sixty-nine patients with SCCHN (6 Stage III and 63 Stage IV patients) were treated with external beam radiotherapy (70 Gy) and simultaneous intravenous chemotherapy with 5FU (600 mg/m(2)/day, Days 1-5) and MC (10 mg/m(2), Days 5 and 36). RESULTS: After a mean follow-up of 28.5 months, 59.4% of patients were alive without disease. Complete response was seen in 76.8% of patients. The 3 years overall survival, locoregional relapse-free survival and disease-free survival was 62.3, 63.1[corrected] and 49.5%, respectively. Treatment was well tolerated (Grade III mucositis in 43.5% and Grade II leukopenia in 5.8%). CONCLUSIONS: This concurrent chemoradiotherapy regimen offers a curative option for our patients where primary and nodal disease is fairly large resulting in hypoxic radioresistant tumors.  相似文献   
10.
Incidental peripheral lesions found during neuroradiological MR examinations with surface coils are reviewed. These include intracranial metastases during orbital examinations, cerebellar and thyroid lesions during cervical spine examinations, and dissecting and saccular abdominal aneurysms, as well as renal and intrapelvic abnormalities during lumbar spine examinations. Because of the reduced field-of-view and rapid signal drop-off in deeper portions of the body when examinations are performed with surface coils, peripheral and deep regions also need careful attention during routine evaluation.  相似文献   
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