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111.
Muhammad Tariq Murtaza Memon Asif Jafferani Sana Shoukat Saqib Ali Gowani Rabeeya Nusrat Mehmood Riaz Junaid Patel Bushra Jamil Raymond A. Smego Jr. 《PloS one》2009,4(10)
Background
Cholera is an important infectious cause of secretory diarrhea. The primary symptom of infection is the sudden onset of watery diarrhea with subsequent volume depletion causing renal insufficiency. The objective of this research is to study the level of dehydration at presentation and subsequent fluid management in patients with cholera.Methods
This study was conducted on 191 patients of Cholera admitted at a tertiary care hospital in Karachi, Pakistan during the period of 5 years. Medical charts were evaluated retrospectively for initial hydration status, baseline lab investigations on admission and discharge and fluid therapy given to all the patients while their stay in the hospital and the data was analyzed on SPSS 15.0.Results
Out of the 191 patients, 83(43%) were males and 108 (57%) were females with mean age of 42.3 years (SD±18.34). The average duration of symptoms was 3.75 days (SD±2.04). Of 191 patients, 175 (92.1%) presented with dehydration, 80 (42.3%) were given Ringer''s Lactate (R/L) + Normal Saline (N/S), 45 (24%) patients were given R/L + N/S + Oral Rehydration Therapy (ORS), 27 (14.3%) of the patients were kept on R/L only and remaining were given various combinations of R/L, N/S, ORS and Dextrose Saline (D/S). On admission mean Blood Urea Nitrogen (BUN) was 24.54 (SD±16.6), mean creatinine was 2.47 (SD±2.35) and mean BUN/Creatinine ratio was 11.63 (SD±5.7).Conclusion
Aggressive fluid rehydration remains the cornerstone of management of cholera. Instead of presenting with a classical BUN/Creatinine ratio of >20∶1, patients with pre-renal failure in cholera may present with a BUN/Creatinine ratio of <15∶1. 相似文献112.
Enver T 《Current biology : CB》1999,9(24):R933-R935
113.
Boron is an essential plant micronutrient, but it is phytotoxic if present in excessive amounts in soil for certain plants
such as Artemisia annua L. that contains artemisinin (an important antimalarial drug) in its areal parts. Artemisinin is a sesquiterpene lactone
with an endoperoxide bridge. It is quite expensive compound because the only commercial source available is A. annua and the compound present in the plant is in very low concentration. Since A. annua is a major source of the antimalarial drug and B stress is a deadly threat to its cultivation, the present research was conducted
to determine whether the exogenous application of methyl jasmonate (MeJA) could combat the ill effects of excessive B present
in the soil. According to the results obtained, the B toxicity induced oxidative stress and reduced the stem height as well
as fresh and dry masses of the plant remarkably. The excessive amounts of soil B also lowered the net photosynthetic rate,
stomatal conductance, internal CO2 concentration and total chlorophyll content in the leaves. In contrast, the foliar application of MeJA enhanced the growth
and photosynthetic efficiency both in the stressed and non-stressed plants. The excessive B levels also increased the activities
of antioxidant enzymes, such as catalase, peroxidase and superoxide dismutase. Endogenous H2O2 and O2− levels were also high in the stressed plants. However, the MeJA application to the stressed plants reduced the amount of
lipid peroxidation and stimulated the synthesis of antioxidant enzymes, enhancing the content and yield of artemisinin as
well. Thus, it was concluded that MeJA might be utilized in mitigating the B toxicity and improving the content and yield
of artemisinin in A. annua plant. 相似文献
114.
Mohd Idrees M. Naeem Tariq Aftab M. Masroor A. Khan Moinuddin 《Acta Physiologiae Plantarum》2011,33(3):987-999
A pot experiment was conducted to find out whether the foliar spray of salicylic acid (SA) could successfully ameliorate the
adverse effects of salinity stress on periwinkle. Thirty-day-old plants were supplied with Control; 0 mM NaCl + 10−5 M SA (T1); 50 mM NaCl + 0 SA (T2); 100 mM NaCl + 0 SA (T3); 150 mM NaCl + 0 SA (T4); 50 mM NaCl + 10−5 M SA (T5); 100 mM NaCl + 10−5 M SA (T6); 150 mM NaCl + 10−5 M SA (T7). The plants were sampled 90 days after sowing to assess the effect of SA on stressed and unstressed plants. Salt stress
significantly reduced the growth attributes including plant height, leaf-area index, shoot and root fresh weights, shoot and
root dry weights. Increasing NaCl concentrations led to a gradual decrease in photosynthetic parameters and activities of
nitrate reductase and carbonic anhydrase. Ascorbic acid, total alkaloids and antioxidants enzymes superoxide dismutase, catalase
and peroxidase also declined in NaCl-treated plants. The plants, undergoing NaCl stress, exhibited a significant increase
in electrolyte leakage and proline content. Foliar application of SA (10−5 M) reduced the damaging effect of salinity on plant growth and accelerated the restoration of growth processes. It not only
improved the growth parameters but also reversed the effects of salinity. Total alkaloid content was improved by SA application
both in unstressed and stressed plants. The highest level of total alkaloid content recorded in leaves of SA-treated stressed
plants was 11.1%. Foliar spray of SA overcame the adverse effect of salinity by improving the content of vincristine (14.0%)
and vinblastine (14.6%) in plants treated with 100 M NaCl. 相似文献
115.
Ismahil MA Hamid T Haberzettl P Gu Y Chandrasekar B Srivastava S Bhatnagar A Prabhu SD 《American journal of physiology. Heart and circulatory physiology》2011,301(5):H2050-H2060
Environmental triggers of dilated cardiomyopathy are poorly understood. Acute exposure to acrolein, a ubiquitous aldehyde pollutant, impairs cardiac function and cardioprotective responses in mice. Here, we tested the hypothesis that chronic oral exposure to acrolein induces inflammation and cardiomyopathy. C57BL/6 mice were gavage-fed acrolein (1 mg/kg) or water (vehicle) daily for 48 days. The dose was chosen based on estimates of human daily unsaturated aldehyde consumption. Compared with vehicle-fed mice, acrolein-fed mice exhibited significant (P < 0.05) left ventricular (LV) dilatation (LV end-diastolic volume 36 ± 8 vs. 17 ± 5 μl), contractile dysfunction (dP/dt(max) 4,697 ± 1,498 vs. 7,016 ± 1,757 mmHg/s), and impaired relaxation (tau 15.4 ± 4.3 vs. 10.4 ± 2.2 ms). Histological and biochemical evaluation revealed myocardial oxidative stress (membrane-localized protein-4-hydroxy-trans-2-nonenal adducts) and nitrative stress (increased protein-nitrotyrosine) and varying degrees of plasma and myocardial protein-acrolein adduct formation indicative of physical translocation of ingested acrolein to the heart. Acrolein also induced myocyte hypertrophy (~2.2-fold increased myocyte area, P < 0.05), increased apoptosis (~7.5-fold), and disrupted endothelial nitric oxide synthase in the heart. DNA binding studies, immunohistochemistry, and PCR revealed significant (P < 0.05) activation of nuclear factor-κB in acrolein-exposed hearts, along with upregulated gene expression of proinflammatory cytokines tumor necrosis factor-α and interleukin-1β. Long-term oral exposure to acrolein, at an amount within the range of human unsaturated aldehyde intake, induces a phenotype of dilated cardiomyopathy in the mouse. Human exposure to acrolein may have analogous effects and raise consideration of an environmental, aldehyde-mediated basis for heart failure. 相似文献
116.
Uzma Majid Mahmooduzzafar Tariq Omar Siddiqi Muhammad Iqbal 《Acta Physiologiae Plantarum》2014,36(2):307-314
Seeds of Cassia angustifolia Vahl., treated with various concentrations (0, 0.1, 0.15, 0.2 and 0.25 %) of Mancozeb, a broad-spectrum contact fungicide, were sown in field conditions to study the effect of the treatments on lipid peroxidation, proline accumulation and modulation of antioxidant system of seedlings obtained. Significant increase over the control was observed in treated plants for thiobarbituric acid-reactive substances content (up to 207 %), proline content (96 %) and total glutathione content (144 %), whereas the total ascorbate content decreased by 44 %. Increased enzymatic activity was recorded for ascorbate peroxidase (63 %), glutathione reductase (154 %) and superoxide dismutase (109 %), whereas catalase activity decreased by 58 % with 0.25 % Mancozeb treatment. The changes observed were dose-dependent, showing a strong correlation with the level of treatment. 相似文献
117.
118.
119.
Maria Hanif Muhammad Mahmood Tariq Ludwig Ralf Ayub Khurshid 《Journal of molecular modeling》2014,20(6):1-8
The thermodynamic stabilities and IR spectra of the three water clusters (H2O)20, (H2O)54,, and (H2O)100 are studied by quantum-chemical computations. After full optimization of the (H2O)20,54,100 structures using the hybrid density functional B3LYP together with the 6-31+G(d,p) basis set, the electronic energies, zero-point energies, internal energies, enthalpies, entropies, and Gibbs free energies of the water clusters at 298 K are investigated. The OH stretching vibrational IR spectra of (H2O)20,54,100 are simulated and split into sub-spectra for different H-bond groups depending on the conformations of the hydrogen bonds. From the computed spectra the different spectroscopic fingerprint features of water molecules in different H-bond conformations in the water clusters are inferred. 相似文献
120.
Daniel E. Janes Christopher L. Organ Rami Stiglec Denis O'Meally Stephen D. Sarre Arthur Georges Jennifer A. M. Graves Nicole Valenzuela Robert A. Literman Kim Rutherford Neil Gemmell John B. Iverson Jeffrey W. Tamplin Scott V. Edwards Tariq Ezaz 《Biology letters》2014,10(12)
In reptiles, sex-determining mechanisms have evolved repeatedly and reversibly between genotypic and temperature-dependent sex determination. The gene Dmrt1 directs male determination in chicken (and presumably other birds), and regulates sex differentiation in animals as distantly related as fruit flies, nematodes and humans. Here, we show a consistent molecular difference in Dmrt1 between reptiles with genotypic and temperature-dependent sex determination. Among 34 non-avian reptiles, a convergently evolved pair of amino acids encoded by sequence within exon 2 near the DM-binding domain of Dmrt1 distinguishes species with either type of sex determination. We suggest that this amino acid shift accompanied the evolution of genotypic sex determination from an ancestral condition of temperature-dependent sex determination at least three times among reptiles, as evident in turtles, birds and squamates. This novel hypothesis describes the evolution of sex-determining mechanisms as turnover events accompanied by one or two small mutations. 相似文献