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81.
We examined the roles of lithology, topography, vegetation and fire in generating local-scale (<1 km2) soil spatial variability in a seasonally dry tropical forest (SDTF) in southern India. For this, we mapped soil (available nutrients, Al, total C, pH, moisture and texture in the top 10cm), rock outcrops, topography, all native woody plants ≥1 cm diameter at breast height (DBH), and spatial variation in fire frequency (times burnt during the 17 years preceding soil sampling) in a permanent 50-ha plot. Unlike classic catenas, lower elevation soils had lesser moisture, plant-available Ca, Cu, Mn, Mg, Zn, B, clay and total C. The distribution of plant-available Ca, Cu, Mn and Mg appeared to largely be determined by the whole-rock chemical composition differences between amphibolites and hornblende-biotite gneisses. Amphibolites were associated with summit positions, while gneisses dominated lower elevations, an observation that concurs with other studies in the region which suggest that hillslope-scale topography has been shaped by differential weathering of lithologies. Neither NO3−-N nor NH4+-N was explained by the basal area of trees belonging to Fabaceae, a family associated with N-fixing species, and no long-term effects of fire on soil parameters were detected. Local-scale lithological variation is an important first-order control over soil variability at the hillslope scale in this SDTF, by both direct influence on nutrient stocks and indirect influence via control of local relief. 相似文献
82.
Background
One of the largest cross-sectional study in recent years was carried out to investigate the prevalence of intestinal parasitic infections among urban and rural school children from five states namely Selangor, Perak, Pahang, Kedah and Johor in Peninsula Malaysia. This information would be vital for school authorities to influence strategies for providing better health especially in terms of reducing intestinal parasitism.Methods and Principal Findings
A total of 3776 stool cups was distributed to 26 schools throughout the country. 1760 (46.61%) responded. The overall prevalence of intestinal parasitic infection in both rural and urban areas was 13.3%, with Blastocystis sp (10.6%) being the most predominant, followed by Trichuris trichiura (3.4%), Ascaris lumbricoides (1.5%) and hook worm infection (0.9%). Only rural school children had helminthic infection. In general Perak had the highest infection (37.2%, total, n = 317), followed by Selangor (10.4%, total, n = 729), Pahang (8.6%, total, n = 221), Kedah (6.2%, total, n = 195) and Johor (3.4%, total, n = 298). School children from rural schools had higher infection (13.7%, total, n = 922) than urban school children (7.2%, total, n = 838). Subtype (ST) 3 (54.3%) is the most predominant ST with persons infected with only ST1 and ST3 showing symptoms. Blastocystis sp infection significantly associated with low household income, low parent’s education and presence of symptoms (p<0.05).Conclusion
It is critical that we institute deworming and treatment to eradicate the parasite especially in rural school children. 相似文献83.
84.
CaS:Ce3+ is an efficient green‐emitting (535 nm) phosphor, excitable with blue light (450–470 nm) and was synthesized via a solid‐state reaction method by heating under a reducing atmosphere. The luminescent properties, photoluminescent (PL) excitation and emission of the phosphor were analyzed by spectrofluorophotometry. The excitation and emission peaks of the CaS:Ce3+ phosphor lay in the visible region, which made them relevant for light‐emitting diode (LED) application for the generation of white light. Judd‐Oflet parameters were calculated and revealed that green light emitted upon blue illumination. The prepared phosphor had strong blue absorption at 470 nm and a broad green emission band range from 490–590 nm with the peak at 537 nm. The characteristics of the CaS:Ce3+ phosphor make it suitable for use as a wavelength tunable green emitting phosphor for three band white LEDs pumped by a blue LED (470 nm). The Commission International de l'Eclairage co‐ordinates were calculated by a spectrophotometric method using the spectral energy distribution (0.304, 0.526) and confirm the green emission. The potential application of this phosphor is as a phosphor‐converted white light‐emitting diode. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
85.
Shivani Rai Paliwal Rishi Paliwal Govind Prasad Agrawal Suresh Prasad Vyas 《Journal of liposome research》2016,26(4):276-287
Context: Surface-modified pH-sensitive liposomal system may be useful for intracellular delivery of chemotherapeutics.Objective: Achieving site-specific targeting with over-expressed hyaluronic acid (HA) receptors along with using pH sensitive liposome carrier for intracellular drug delivery was the aim of this study.Materials and methods: Stealth HA-targeted pH-sensitive liposomes (SL-pH-HA) were developed and evaluated to achieve effective intracellular delivery of doxorubicin (DOX) vis–a-vis enhanced antitumor activity.Results: The in vitro release studies demonstrated that the release of DOX from SL-pH-HA was pH-dependent, i.e. faster at mildly acidic pH ~5, compared to physiological pH ~7.4. SLpH-HA was evaluated for their cytotoxicity potential on CD44 receptor expressing MCF-7 cells. The half maximal inhibitory concentration (IC50) of SL-pH-HA and SL-HA were about 1.9 and 2.5?μM, respectively, after 48?h of incubation. The quantitative uptake study revealed higher localization of targeted liposomes in the receptor positive cells, which was further confirmed by fluorescent microscopy. The antitumor efficacy of the DOX-loaded HA-targeted pH-sensitive liposomes was also verified in a tumor xenograft mouse model.Discussion: DOX was efficiently delivered to the tumor site by active targeting via HA and CD44 receptor interaction. The major side-effect of conventional DOX formulation, i.e. cardiotoxicity was also estimated by measuring serum enzyme levels of LDH and CPK and found to be minimized with developed formulation. Overall, HA targeted pH-sensitive liposomes were significantly more potent than the non-targeted liposomes in cells expressing high levels of CD44.Conclusion: Results strongly implies the promise of such liposomal system as an intracellular drug delivery carrier developed for potential anticancer treatment. 相似文献
86.
Sharvari S. Deshpande Harishankar Nemani Suresh Pothani Nafisa H. Balasinor 《Reproductive biology》2019,19(3):303-308
Obesity is emerging as a potential risk factor for male infertility. It is a multifactorial disorder with primarily genetic and/or environmental factors. Our earlier studies have shown differential effects of genetically inherited-and high fat diet induced-obesity on hormones, fertility and spermatogenesis in adult male rats. In the present study, we assessed the effect of high fat diet induced – and genetically inherited – obesity on the underlying molecular mechanisms affecting spermatogenesis. The expression of hormone receptors, cytokines and markers of oxidative stress as well as cell cycle mediators were affected in both the obese groups, however, the changes were different in the two groups. This could be due to difference in fat distribution between the two types of obese groups. Altered expression of hormone receptors, cytokines, cell cycle mediators and differential effects on oxidative stress could be the plausible reason for differential changes in germ cell population in both the groups. 相似文献
87.
Anil Chekuri Katarzyna Zientara‐Rytter Angel Soto‐Hermida Shyamanga Borooah Marina Voronchikhina Pooja Biswas Virender Kumar David Goodsell Caroline Hayward Peter Shaw Chloe Stanton Donita Garland Suresh Subramani Radha Ayyagari 《Aging cell》2019,18(6)
Late‐onset retinal degeneration (L‐ORD) is an autosomal dominant macular degeneration characterized by the formation of sub‐retinal pigment epithelium (RPE) deposits and neuroretinal atrophy. L‐ORD results from mutations in the C1q‐tumor necrosis factor‐5 protein (CTRP5), encoded by the CTRP5/C1QTNF5 gene. To understand the mechanism underlying L‐ORD pathology, we used a human cDNA library yeast two‐hybrid screen to identify interacting partners of CTRP5. Additionally, we analyzed the Bruch's membrane/choroid (BM‐Ch) from wild‐type (Wt), heterozygous S163R Ctrp5 mutation knock‐in (Ctrp5S163R/wt), and homozygous knock‐in (Ctrp5S163R/S163R) mice using mass spectrometry. Both approaches showed an association between CTRP5 and HTRA1 via its C‐terminal PDZ‐binding motif, stimulation of the HTRA1 protease activity by CTRP5, and CTRP5 serving as an HTRA1 substrate. The S163R‐CTRP5 protein also binds to HTRA1 but is resistant to HTRA1‐mediated cleavage. Immunohistochemistry and proteomic analysis showed significant accumulation of CTRP5 and HTRA1 in BM‐Ch of Ctrp5S163R/S163R and Ctrp5S163R/wt mice compared with Wt. Additional extracellular matrix (ECM) components that are HTRA1 substrates also accumulated in these mice. These results implicate HTRA1 and its interaction with CTRP5 in L‐ORD pathology. 相似文献
88.
As Romanians prepared to celebrate 100 years of the '‘Great Unification of 1918?' which united all provinces into one Romania, the 12th Central and Eastern European Proteomic Conference (CEEPC) jointly with the 39th Anniversary of the Institute of Cellular Biology and Pathology '‘N. Simionescu’' (ICBP-NS), held their inaugural meeting at the Romanian Academy in Bucharest – a national forum of highest scientific recognition. With an exciting theme entitled, ‘Advances in Proteomics and Progress in Precision Medicine’, delegates gathered to debate Precision medicine’s revolution in diagnosis and treatment, which now accounts for predictive, preventative, and targeted treatment strategies with informed decisions according to individual’s unique clinical, molecular and genetic profile. Proteomics has a pivotal role to play in furthering precision health and medicine for the benefit of mankind. To this end, CEEPC continues to drive advances in proteomics, metabolomics, and diseases as well as raising awareness of pressing global humanitarian and health-care issues including mental health diseases, aging, chronic diseases, global epidemics and environmental issues. Today, CEEPC is a well-recognized major annual conference with a focused vision and a highly valued ideology as it continues to propagate scientific, medical and proteomic collaborations whilst expanding as more Eastern European countries prepare to join. 相似文献
89.
Yanting Wang Michael S. Sharbaugh Andrew D. Althouse Suresh Mulukutla Samir Saba 《Indian pacing and electrophysiology journal》2019,19(1):4-6
Introduction
With the recent publication of the negative DANISH trial, the mortality benefit of the implantable cardioverter-defibrillator (ICD) has been put in question in patients with non-ischemic cardiomyopathy (NICM). Because a majority of patients in DANISH receive cardiac resynchronization therapy (CRT) devices, we investigated in the present study the survival of recipients of CRT pacemakers (CRT-P) versus CRT ICDs (CRT-D) in a cohort of older (≥75 years) NICM patients at our institution.Methods
A total of 135 NICM patients with CRT device were identified (42 with CRT-P and 93 with CRT-D) and were followed to the endpoint of all-cause mortality. Overall survival was compared between the CRT-P and CRT-D groups with adjustment for differences in baseline characteristics.Results
Over a median follow-up of 46 months from the time of CRT device implantation, there were 54 total deaths (40%): 14 in the CRT-P (33%) and 40 in the CRT-D (43%) groups. Overall, CRT-P recipients had similar unadjusted mortality compared to CRT-D recipients (hazard ratio [HR] 1.04, 95% confidence interval [CI] 0.56–1.93), and this remained unchanged after adjusting for unbalanced covariates (HR 0.95, 95% CI 0.47–1.89) including left ventricular ejection fraction, used of angiotensin converting enzyme inhibitors/angiotensin receptor blockers, and the Charlson comorbidity index.Conclusion
Our data support that in older NICM patients with CRT devices, the addition of ICD therapy does not improve survival. 相似文献90.
Enrico Baria Simone Morselli Suresh Anand Riccardo Fantechi Gabriella Nesi Mauro Gacci Marco Carini Sergio Serni Riccardo Cicchi Francesco S. Pavone 《Journal of biophotonics》2019,12(11)
Urothelial carcinoma (UC) is the most common bladder tumour. Proper treatment requires tumour resection for diagnosing its grade (aggressiveness) and stage (invasiveness). White‐light cystoscopy and histopathological examination are the gold standard procedures for clinical and histopathological diagnostics, respectively. However, cystoscopy is limited in terms of specificity, histology requires long tissue processing, both procedures rely on operator's experience. Multimodal optical spectroscopy can provide a powerful tool for detecting, staging and grading bladder tumours in a fast, reliable and label‐free modality. In this study, we collected fluorescence, Raman and reflectance spectra from 50 biopsies obtained from 32 patients undergoing transurethral resection of bladder tumour using a multimodal fibre‐probe. Principal component analysis allowed distinguishing normal from pathological tissues, as well as discriminating tumour stages and grades. Each individual spectroscopic technique provided high specificity and sensitivity in classifying all tissues; however, a multimodal approach resulted in a considerable increase in diagnostic accuracy (≥95%), which is of paramount importance for tumour grading and staging. The presented method offers the potential for being applied in cystoscopy and for providing an automated diagnosis of UC at the clinical level, with an improvement with respect to current state‐of‐the‐art procedures. 相似文献