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61.
Bireshwar Sinha Nidhi Goyal Mohan Kumar Aashish Choudhary Alok Arya Anitha Revi Ankita Dutta Deepak More Temsunaro Rongsen-Chandola 《PLoS neglected tropical diseases》2022,16(4)
BackgroundOur aim was to estimate the overall and age-specific incidence of lab-confirmed dengue fever using ELISA based assays among children 6 months to 15 years in Delhi.MethodsWe enrolled a cohort of 984 children aged 6 months to <14 years in South Delhi and followed-up weekly for fever for 24 months or till 15 completed years of child-age. Households of the enrolled children were geo-tagged. NS1, IgM and IgG assays were conducted using ELISA method to confirm dengue fever in children with ≥3 consecutive days of fever. Molecular typing was done in a subset of NS1 positive cases to identify the circulating serotypes.Principal findingsWe had a total of 1953 person-years (PY) of follow up. Overall, there were 4208 episodes of fever with peaks during June to November. The overall incidence (95%CI) of fever was 215/100 PY (209 to 222). A total of 74/1250 3-day fever episodes were positive for acute dengue fever (NS1 and/or IgM positive). The overall incidence (95%CI) of acute dengue fever was 37.9 (29.8 to 47.6) per 1000 PY; highest among children aged 5 to 10 years (50.4 per 1000 PY, 95% CI 36.5 to 67.8). Spatial autocorrelation analysis suggested a clustering pattern for the dengue fever cases (Moran’s Index 0.35, z-score 1.8, p = 0.06). Dengue PCR was positive in 16 of the 24 specimens tested; DEN 3 was the predominant serotype identified in 15/24 specimens.ConclusionsWe found a high incidence of dengue fever among under 15-year children with clustering of cases in the community. DEN 3 was the most commonly circulating strain encountered. The findings underscore the need for development of affordable pre-vaccination screening strategy as well as newer dengue vaccines for young children while continuing efforts in vector control. 相似文献
62.
Akhil Kumar Nishank Goyal Nandhini Saranathan Sonam Dhamija Saurabh Saraswat Manoj B Menon Perumal Vivekanandan 《Molecular biology and evolution》2022,39(3)
Depletion of CpG dinucleotides in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genomes has been linked to virus evolution, host-switching, virus replication, and innate immune responses. Temporal variations, if any, in the rate of CpG depletion during virus evolution in the host remain poorly understood. Here, we analyzed the CpG content of over 1.4 million full-length SARS-CoV-2 genomes representing over 170 million documented infections during the first 17 months of the pandemic. Our findings suggest that the extent of CpG depletion in SARS-CoV-2 genomes is modest. Interestingly, the rate of CpG depletion is highest during early evolution in humans and it gradually tapers off, almost reaching an equilibrium; this is consistent with adaptations to the human host. Furthermore, within the coding regions, CpG depletion occurs predominantly at codon positions 2-3 and 3-1. Loss of ZAP (Zinc-finger antiviral protein)-binding motifs in SARS-CoV-2 genomes is primarily driven by the loss of the terminal CpG within the motifs. Nonetheless, majority of the CpG depletion in SARS-CoV-2 genomes occurs outside ZAP-binding motifs. SARS-CoV-2 genomes selectively lose CpGs-motifs from a U-rich context; this may help avoid immune recognition by TLR7. SARS-CoV-2 alpha-, beta-, and delta-variants of concern have reduced CpG content compared to sequences from the beginning of the pandemic. In sum, we provide evidence that the rate of CpG depletion in virus genomes is not uniform and it greatly varies over time and during adaptations to the host. This work highlights how temporal variations in selection pressures during virus adaption may impact the rate and the extent of CpG depletion in virus genomes. 相似文献
63.
Gupta N Goyal N Bhatia N Kamboj KK Rastogi AK 《Indian journal of experimental biology》2001,39(7):623-628
Antigenic characterization of the soluble fraction of axenic amastigotes of Leishmania donovani ( strain Dd8, causative agent of Indian kala-azar) and their comparison with promastigotes is reported. The axenic amastigotes were assessed for their immunological status employing anti-A2 monoclonal antibody which is extremely specific for L. donovani amastigotes. SDS-PAGE of 35[S] methionine labeled proteins of the two parasite stages exhibited few stage specific and some conserved antigens in both the stages. An increased synthesis of heat shock proteins was observed in axenic amastigotes. Western blot experiments employing sera of kala azar positive patients identified immunodominent antigens of 116,83,26 and 12 kDa in axenic amastigotes which were not present in promastigotes. These amastigote stage specific antigens may have immense potential in immunodiagnosis and prophylaxis of kala-azar. 相似文献
64.
Svatikova A Wolk R Wang HH Otto ME Bybee KA Singh RJ Somers VK 《American journal of physiology. Regulatory, integrative and comparative physiology》2004,287(2):R284-R287
Obstructive sleep apnea (OSA) has been increasingly linked to cardiovascular disease, endothelial dysfunction, and oxidative stress, generated by repetitive nocturnal hypoxemia and reperfusion. Circulating free nitrotyrosine has been reported as a novel biomarker of nitric oxide (NO)-induced oxidative/nitrosative stress. Nitrosative stress has been implicated as a possible mechanism for development of cardiovascular diseases. We tested the hypothesis that repetitive severe hypoxemia resulting from OSA would increase NO-mediated oxidative stress. We studied 10 men with newly diagnosed moderate to severe OSA who were free of other diseases, had never been treated for OSA, and were taking no medications. Nitrotyrosine measurements, performed by liquid chromatography-tandem mass spectrometry, were made before and after untreated apneic sleep. We compared free nitrotyrosine levels in these patients with those obtained at similar times in 10 healthy male control subjects without OSA, with similar age and body mass index. Evening baseline nitrotyrosine levels were similar before sleep in the control and OSA groups [0.16 +/- 0.01 and 0.15 +/- 0.01 ng/ml, respectively, P = not significant (NS)]. Neither normal nor disturbed apneic sleep led to significant changes of plasma nitrotyrosine (morning levels: control group 0.14 +/- 0.01 ng/ml; OSA group 0.15 +/- 0.01 ng/ml, P = NS). OSA was not accompanied by increased circulating free nitrotyrosine either at baseline or after sleep. This observation suggests that repetitive hypoxemia during OSA does not result in increased NO-mediated oxidative/nitrosative stress in otherwise healthy subjects with OSA. 相似文献
65.
Differential modulation of voltage-dependent K+ currents in colonic smooth muscle by oxidants 总被引:1,自引:0,他引:1
The effect of oxidants on voltage-dependent K+ currents was examined in mouse colonic smooth muscle cells. Exposure to either chloramine-T (Ch-T), an agent known to oxidize both cysteine and methionine residues, or the colon-specific oxidant monochloramine (NH2Cl) completely suppressed the transient outward K+ current (Ito) while simultaneously enhancing the sustained delayed rectifier K+ current (Idr). In contrast, the cysteine-specific oxidants hydrogen peroxide (H2O2) and 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) exhibited partial and slow suppression of Ito by inducing a shift in channel availability of -18 mV without affecting Idr. After enhancement by NH2Cl or Ch-T, Idr was sensitive to 10 mM tetraethylammonium but not to other K+ channel blockers, suggesting that it represented activation of the resting Idr and not a separate K+ conductance. Extracellular dithiothreitol (DTT) partially reversed the effect of H2O2 and DTNB on Ito but not the actions of NH2Cl and Ch-T on either Idr or Ito. Dialysis of myocytes with GSH (5 mM) or DTT (5 mM) prevented suppression of Ito by H2O2 and DTNB but did not alter the effects of NH2Cl or Ch-T on either Idr or Ito. Ch-T and NH2Cl completely blocked Ito generated by murine Kv4.1, 4.2, and 4.3 in Xenopus oocytes, an effect not reversible by intracellular DTT. In contrast, intracellular DTT reversed the effect of H2O2 and DTNB on the cloned channels. These results suggest that Ito is suppressed via modification of both methionine and cysteine residues, whereas enhancement of Idr likely results from methionine oxidation alone. colon; colitis; redox; ion channel 相似文献
66.
Three deoxypreussomerins, palmarumycins CP1, JC1 and JC2, have been isolated from a collection of the stems of Jatropha curcas. The second and third compounds are antibacterial constituents which were characterized from spectral evidence. The X-ray crystallographic structure of palmarumycin JC1 was also studied. Deoxypreussomerins have been obtained here from a plant source in appreciable quantities. 相似文献
67.
Background. Studies on eradication therapy in developing countries have shown a success rate of 70–85%, which is suboptimal. Duration of therapy may be an important factor dictating eradication success in such regions. Aim. The study was undertaken to evaluate the effect of increasing the treatment period on eradication of Helicobacter pylori in duodenal ulcer disease. Methods. A randomized trial was carried out in which 64 consecutive H. pylori‐infected patients with duodenal ulcer disease were enrolled. The patients were randomized to one of the three trial arms. Therapy consisted of lansoprazole 30 mg twice a day (b.i.d.), amoxycillin 1 g b.i.d. and tinidazole 500 mg b.i.d. The treatment period was 1 week in group I, 2 weeks in group II and 3 weeks in group III. At inclusion, patients underwent endoscopy and the presence of H. pylori was documented by a positive urease test and C14 urea breath test. Four weeks after completion of eradication therapy, the patients were subjected to repeat endoscopy to assess ulcer healing and tests for H. pylori infection. Results. Sixty‐four patients (55 male and nine female; mean age 35.5 years) were enrolled in each group. The H. pylori eradication rate for group I (1 week of therapy) was 47.6%, that for group II (2 weeks of therapy) was 80%, and that for group III (3 weeks of therapy) was 91.3% (p = .003). The ulcer healing rates were 71.4, 80 and 95.6% in groups I, II and III, respectively (p = .09). Conclusion. The 3‐week regimen significantly improved the eradication rate as compared with the 1‐week regime. Increasing the duration of therapy significantly improved the chances of eradication of H. pylori in duodenal ulcer disease. 相似文献
68.
Neurotrophin proteins are essential for the survival, differentiation, and maintenance of neurons in the peripheral and central nervous systems. Recent studies have shown that the unprocessed proforms of the neurotrophins are preferential high-affinity ligands for p75NTR and potent inducers of p75NTR-mediated cell death. Here, we explore differences in the selective constraints acting on the proregions of the three avian neurotrophin genes—NT-3, BDNF, and NGF—in an explicit phylogenetic context. We found a 50-fold difference in levels of constraint as estimated by d
N/d
S ratios, with the NGF proregion showing the lowest degree of constraint and BDNF the highest. These patterns suggest that the high conservation exhibited by the BDNF proregion results from intense functional constraints that are relaxed in NGF and somewhat relaxed in NT-3. The proregion of BDNF is likely to have a function that differentiates it from the corresponding regions of the NGF and NT-3 genes, suggesting that BDNF is the avian neurotrophin most likely to be used both in its precursor and mature forms in vivo. 相似文献
69.
In the frame of the activities carried out to exploit Sicilian local cultivars of brassicas, we focused our attention on some of the potential health compounds of various local cruciferous crops. These compounds are of interest to improve the quality of the produce with the aim to develop new cultivars capable of providing functional foods able to prevent disease. In this context, we surveyed for the presence of specific glucosinolates in local cultivars of broccoli, cauliflower, kale, and in some wild species widespread in Sicily, using as control various commercial cultivars. Glucosinolate composition varied extensively among species and crops of the same species, such as cauliflower, broccoli and kale. Cultivar variation for glucosinolate profile was also observed for some crops. For example, Sicilian cultivars of cauliflower possessing colored curds displayed a high content of glucosinolates, glucoraphanin in particular, compared to white curd commercial cultivars. Also some wild species had a high content of other glucosinolates. 相似文献
70.
DCMU inhibits in vivo nitrate reduction in illuminated barley (C(3)) leaves but not in maize (C(4)): a new mechanism for the role of light? 总被引:1,自引:0,他引:1
The leaves of C(4) plants possess a superior metabolic efficiency not only in terms of photosynthetic carbon assimilation, but also in terms of inorganic nitrogen assimilation, when compared to C(3)plants. In vivo nitrate assimilation efficiency of leaves is dependent on light, but the obligatory presence of light has been debated and its role remains confounded. This problem has not been addressed from the standpoint of the C(3) vs. C(4) nature of the species investigated, which may actually hold the key to resolve the controversy. Here, we present the first report providing evidence for differential photo-regulation of leaf nitrate reduction in barley ( Hordeum vulgare L.) vs. maize ( Zea mays L.) plants, which may help explain the superior nitrogen-use efficiency (and hence superior productivity) of maize plants. The novel finding that carbohydrate-depleted maize leaves were able to reduce nitrate when photosynthesis was inhibited by 3-(3',4'-dichlorophenyl)-1,1'-dimethylurea (DCMU) in the presence of light, raises a very important question about the possibilities of a new photo-regulatory mechanism for supporting nitrate reduction in maize leaves operating independently of photosynthetic carbon dioxide fixation. On the other hand, leaves of barley could not carry out any in vivo nitrate assimilation, whatsoever, under these conditions. We find another fundamental difference between the two species in terms of differential regulation of nitrate reductase (NR; EC 1.6.6.1). In barley leaves, NR activity and activation state remained unaffected due to DCMU, but in sharp contrast, both were appreciably upregulated in maize. Collectively, the results indicate that enzyme capacity is not limiting for nitrate reduction in leaves, as the NR activity was higher in barley than in maize. The maize leaves may have had a selective advantage due to C(4) morphology/metabolism in terms of maintaining a better reductant/carbon skeleton supply for nitrate reduction. 相似文献