Optimization and characterization of hybrid bio-briquettes produced from the mixture of sawdust, sugarcane bagasse, and paddy straw.

Biomass briquetting is a viable densification technique that converts waste biomass materials into useful products and alternative energy. This work explores the characteristics and optimization of hybrid bio-briquette production by combining crop residues (paddy straw) and solid biomass materials (sawdust and sugarcane bagasse). A total number of 20 briquettes were fabricated with three input factors: sawdust (SD), sugarcane bagasse (SB), and paddy straw (PS) based on the faced-centered central composite design (FCCCD) approach in the laboratory to investigate the calorific value (CV) and ash content (AC). The bomb calorimeter technique was used to evaluate the briquette's calorific value and ash content. The proposed work focused on optimizing the briquette input parameters (SD, SB, and PS) and output responses (CV and AC) using analysis of variance (ANOVA) and response surface methodology (RSM) and hybrid artificial neural network-integrated with multi-objective genetic algorithms (ANN-MOGA). This study shows that the MOGA-ANN-based model results in the best value of CV (17.07 MJ/kg) and AC (1.95%) with optimal input parameters SD (39.99 g), SB (29.02 g), and PS (69.02 g). The optimal results observed from the MOGA-ANN model have also been validated experimentally. The Fourier transform infrared (FTIR) spectroscopy investigation reveals that biomass briquettes are the sustainable and environment-friendly option of fossil fuels for power generation and indoor cooking. The study suggests a strategy for minimizing agro-waste, which may be converted into future fuel in the form of briquettes.

Heat storage material: a hope in solar thermal.

Solar energy is a vast renewable energy source, but uncertainty in the demand and supply of energy due to various geographical regions raises a question mark. Therefore, the present manuscript includes a review to overcome this uncertainty by utilizing various thermal energy storage systems. Phase change material is the most preferred thermal energy storage system because of its high-energy storage density. The low thermal conductivity is the critical problem in phase change material that can be overcome by integrating metallic foam, carbon fiber, and metallic fins in the phase change material container. The inclusion of metallic foam limited to 0.1-3% of the Phase change material (PCM) weight leads to a slight change in thermal conductivity but a high cost. It was also seen that the addition of carbon 0.1 to 9% of the PCM weight could improve the performance of PCM. The inclusion of a metallic fin improves the thermal conductivity with the various shapes and sizes of the fin. It is found that metallic foam composites have better performance than carbon composite and metallic fin inclusion.

Performance enhancement of the photovoltaic system with different cooling methods.

Solar energy has been a vital renewable energy source for humanity for decades. Researchers have proposed many strategies to harness the same but solar photovoltaic (PV) is the only technology which has reached commercial scale and highly successful in meeting renewable energy goals of many countries. The major drawback of PV systems is that increase in the temperature of solar cell of the PV module beyond the threshold limit brings down its electrical efficiency (EE). Hence, this review paper discusses the different cooling techniques responsible for reducing the cell temperature, which in turn increases not only its EE, but also collection of the thermal energy that is otherwise considered to dampen the performance of the PV system. A brief study on PV with air cooling, photovoltaic thermal (PVT) with water cooling, PVT/PCM with and without fins, PVT integrated with nanofluids has been done in this review paper. PVT hybrid systems are the need of hour to get the optimum efficiency. Amongst the PVT systems, the performance analysis of PV integrated with the nanofluid is discussed and it is found to give the maximum cell temperature reduction. Since reduction in the cell temperature directly relates to better efficiency, PVT system using nanofluid as a cooling medium gives the best overall efficiency (OE) followed by PVT system incorporating water and air respectively. This review paper also gives spotlight to the real-time usages of PCM and nanofluids for the effective cooling ability especially in the case of PV module.

Review on performance assessment of solar stills using computational fluid dynamics (CFD).

Environmental pollution and water resource management are some of the biggest challenges for the twenty-first century. The utilization of solar energy for water purification through solar stills is an environmental friendly and sustainable approach. Computational fluid dynamics (CFD) is a valuable and cost-effective tool for the simulation of fluid and thermal phenomena in solar stills as well as for their optimization for maximum productivity. The objective of the current study is to present a comprehensive review of the significance of the CFD tool in analysis, performance estimation, and design improvements of solar still. Various studies in this direction are classified according to the comprehensiveness of the modeling approach employed. The approaches are classified into three categories. The assumptions and governing equations for various approaches are presented. It is highlighted that the relatively simpler CFD modeling of only the humid air zone in the solar still, which relies on the availability of experimental data, the modeling approach has now evolved to an advanced level and can give predictive estimates by using only the ambient atmospheric conditions and solar irradiation as input. Various studies are also classified based on configurations, computational domain, and operational and geometrical parametric range. The key results from various CFD studies are summarized.

The diagnostic and prognostic utility of insulin growth factor of squamous cell carcinoma in oral cavity.

OBJECTIVE: The present study was conducted to find the utility of insulin growth factors (IGFs) as diagnostic and prognostic biochemical parameters in patients suffering from squamous cell carcinoma of oral cavity. MATERIALS AND METHODS: A total of 360 male and female patients diagnosed with precancerous conditions (PCC) and oral squamous cell carcinoma (OSCC) of Stage I to IV were selected for the present study. Patients were interviewed using a structured questionnaire to ascertain their demographic and medical history. After completing the history and physical examination, patients were subjected to routine blood investigations along with determining insulin growth factor (IGF-1, IGFBP-3) levels. The data obtained were then subjected to statistical analysis using SPSS 20.0 version. RESULTS: The mean values of IGF-1, insulin-like growth factor-binding protein-3 (IGFBP-3), and ratio of IGF-1 and IGFBP-3 were obtained. The intergroup comparison was done between PCC and all the stages of OSCC for all the IGFs. The result obtained was found to be statistically significant (P < 0.05). CONCLUSION: The present study concluded that a positive correlation was observed for various insulin growth factors (IGF-1, IGFBP-3; and ratio of IGF-1 and IGFBP-3) between OSCC and PCC such as erythroplakia and oral submucous fibrosis. Thus, the study highlighted the use of IGFs as diagnostic and prognostic parameters in patients suffering from cancerous conditions.

Ultrasound-assisted regeneration of zeolite/water adsorption pair.

The use of ultrasound to enhance the regeneration of zeolite 13X for efficient utilization of thermal energy was investigated as a substitute to conventional heating methods. The effects of ultrasonic power and frequency on the desorption of water from zeolite 13X were analyzed to optimize the desorption efficiency. To determine and justify the effectiveness of incorporating ultrasound from an energy-savings point of view, an approach of constant overall input power of 20 or 25 W was adopted. To measure the extent of the effectiveness of using ultrasound, the ultrasonic-power-to-total power ratios of 0.2, 0.25, 0.4 and 0.5 were investigated and the results compared with those of no-ultrasound (heat only) at the same total power. To analyze the effect of ultrasonic frequency, identical experiments were performed at three nominal ultrasonic frequencies of ~28, 40 and 80 kHz. The experimental results showed that using ultrasound enhances the regeneration of zeolite 13X at all the aforementioned power ratios and frequencies without increasing the total input power. With regard to energy consumption, the highest energy-savings power ratio (0.25) resulted in a 24% reduction in required input energy and with an increase in ultrasonic power, i.e. an increase in acoustic-to-total power ratio, the effectiveness of applying ultrasound decreased drastically. At a power ratio of 0.2, the time required for regeneration was reduced by 23.8% compared to the heat-only process under the same experimental conditions. In terms of ultrasonic frequency, lower frequencies resulted in higher efficiency and energy savings, and it was concluded that the effect of ultrasonic radiation becomes more significant at lower ultrasonic frequencies. The observed inverse proportionality between the frequency and ultrasound-assisted desorption enhancement suggests that acoustic dissipation is not a significant mechanism to enhance mass transfer, but rather other mechanisms must be considered.

Large ossifying fibroma of jaw bone: a rare case report.

Ossifying fibroma (OF) is classified as, and behaves like, a benign bone neoplasm. It is often considered to be a type of fibro-osseous lesion (FOL). It can affect both mandible and the maxilla, particularly the mandible. This bone tumour consists of highly cellular, fibrous tissue that contains varied amounts of bone or cementum resembling calcified tissue. Present case is an unusual report of central ossifying fibroma involving the left side of mandible in an 18 year old female patient, who presented to the department with a painless hard swelling. The lesion was treated by surgical resection and reconstruction.

Chagas Cardiomyopathy in New Orleans and the Southeastern United States.

BACKGROUND: Chagas disease (CD), caused by Trypanosoma cruzi, affects 6-7 million people worldwide annually, primarily in Central and South America, and >300,000 people in the United States. CD consists of acute and chronic stages. Hallmarks of acute CD include fever, myalgia, diaphoresis, hepatosplenomegaly, and myocarditis. Symptoms of chronic CD include pathologic involvement of the heart, esophagus, and colon. Myocardial involvement is identifiable by electrocardiogram and cardiac magnetic resonance imaging showing inflammation and left ventricular wall functional abnormalities. CASE REPORTS: We present two cases of CD identified in a single hospital in the Southeastern United States. Case 1 presents a patient with symptoms of anginal chest pain and associated shortness of breath with myocardial involvement suggestive of ischemic infarction but normal coronary arteries. Case 2 describes a patient with no physical symptoms and echocardiogram with ejection fraction of 50% with posterolateral and anterolateral wall hypokinesis but normal coronary arteries. CONCLUSION: With a growing number of immigrants from Central and South America in the United States, it is imperative for clinicians to include CD as part of the differential diagnosis for patients presenting with heart disease who have a history of exposure to T. cruzi endemic areas.

Natural disasters and myocardial infarction: the six years after Hurricane Katrina.

OBJECTIVE: To determine the prolonged effect of Hurricane Katrina on the incidence and timing of acute myocardial infarction (AMI) in the city of New Orleans. PATIENTS AND METHODS: Our study population consisted of 1476 patients with AMI before (August 29, 1999, to August 28, 2005) and after (February 14, 2006, to February 13, 2012) Hurricane Katrina at Tulane University Health Sciences Center to determine post-Katrina alterations in the occurrence and timing of AMI. RESULTS: Compared with pre-Katrina values, there was a more than 3-fold increase in the percentage of admissions for AMI during the 6 years after Hurricane Katrina (P<.001). The percentage of admissions for AMI after Hurricane Katrina increased significantly on nights (P<.001) and weekends (P<.001) and decreased significantly on mornings (P<.001), Mondays (P<.001), and weekdays (P<.001). Patients with AMI after Hurricane Katrina also had significantly higher rates of psychiatric comorbidities (P=.01), smoking (P<.001), lack of health insurance (P<.05), and unemployment (P<.001). CONCLUSION: These results indicate that the effect of natural disasters on the occurrence of AMI may persist for at least a 6-year period and may be related to various factors including population shifts, alterations in the health care system, and the effects of chronic stress and associated behaviors.

Angiotensin II inhibits satellite cell proliferation and prevents skeletal muscle regeneration.

Cachexia is a serious complication of many chronic diseases, such as congestive heart failure (CHF) and chronic kidney disease (CKD). Although patients with advanced CHF or CKD often have increased angiotensin II (Ang II) levels and cachexia and Ang II causes skeletal muscle wasting in rodents, the potential effects of Ang II on muscle regeneration are unknown. Muscle regeneration is highly dependent on the ability of a pool of muscle stem cells (satellite cells) to proliferate and to repair damaged myofibers or form new myofibers. Here we show that Ang II reduced skeletal muscle regeneration via inhibition of satellite cell (SC) proliferation. Ang II reduced the number of regenerating myofibers and decreased expression of SC proliferation/differentiation markers (MyoD, myogenin, and active-Notch) after cardiotoxin-induced muscle injury in vivo and in SCs cultured in vitro. Ang II depleted the basal pool of SCs, as detected in Myf5(nLacZ/+) mice and by FACS sorting, and this effect was inhibited by Ang II AT1 receptor (AT1R) blockade and in AT1aR-null mice. AT1R was highly expressed in SCs, and Notch activation abrogated the AT1R-mediated antiproliferative effect of Ang II in cultured SCs. In mice that developed CHF postmyocardial infarction, there was skeletal muscle wasting and reduced SC numbers that were inhibited by AT1R blockade. Ang II inhibition of skeletal muscle regeneration via AT1 receptor-dependent suppression of SC Notch and MyoD signaling and proliferation is likely to play an important role in mechanisms leading to cachexia in chronic disease states such as CHF and CKD.

Role of ventricular interdependence as an early echocardiographic sign of cardiac surgical postoperative pericardial tamponade.

Pericardial effusions are common in postoperative cardiac surgical patients. Cardiac tamponade occurs relatively infrequently postoperatively and may mimick other conditions, such as heart failure, renal failure, and pulmonary emboli. Echocardiographic examination is frequently hampered in the immediate postoperative period due to suboptimal imaging. The current case series focuses on the echocardiographic findings in tamponade in the postoperative patient with emphasis on ventricular interdependence as an early sign of impending tamponade.

Intracoronary administration of cardiac progenitor cells alleviates left ventricular dysfunction in rats with a 30-day-old infarction.

BACKGROUND: Administration of cardiac progenitor cells (CPCs) 4 hours after reperfusion ameliorates left ventricular function in rats with acute myocardial infarction (MI). Clinically, however, this approach is not feasible, because expansion of autologous CPCs after acute MI requires several weeks. Therefore, we sought to determine whether CPCs are beneficial in the more clinically relevant setting of an old MI (scar). METHODS AND RESULTS: One month after coronary occlusion/reperfusion, rats received an intracoronary infusion of vehicle or enhanced green fluorescent protein-labeled CPCs. Thirty-five days later, CPC-treated rats exhibited more viable myocardium in the risk region, less fibrosis in the noninfarcted region, and improved left ventricular function. Cells that stained positive for enhanced green fluorescent protein that expressed cardiomyocyte, endothelial, and vascular smooth muscle cell markers were observed only in 7 of 17 treated rats and occupied only 2.6% and 1.1% of the risk and noninfarcted regions, respectively. Transplantation of CPCs was associated with increased proliferation and expression of cardiac proteins by endogenous CPCs. CONCLUSIONS: Intracoronary administration of CPCs in the setting of an old MI produces beneficial structural and functional effects. Although exogenous CPCs can differentiate into new cardiac cells, this mechanism is not sufficient to explain the benefits, which suggests paracrine effects; among these, the present data identify activation of endogenous CPCs. This is the first report that CPCs are beneficial in the setting of an old MI when given by intracoronary infusion, the most widely applicable therapeutic approach in patients. Furthermore, this is the first evidence that exogenous CPC administration activates endogenous CPCs. These results open the door to new therapeutic applications for the use of autologous CPCs in patients with old MI and chronic ischemic cardiomyopathy.

The beneficial effects of postinfarct cytokine combination therapy are sustained during long-term follow-up.

We have previously reported that administration of granulocyte colony-stimulating factor (G-CSF)+Flt-3 ligand (FL) or G-CSF+stem cell factor (SCF) improves left ventricular (LV) function and halts LV remodeling at 35 d after myocardial infarction (MI). In the current study, we investigated whether these beneficial effects are sustained in the long term - an issue of fundamental importance for clinical translation. Mice undergoing a 30-min coronary occlusion followed by reperfusion received vehicle (group I), G-CSF+FL (group II), G-CSF+SCF (group III), or G-CSF alone (group IV) starting 4 h after reperfusion and were euthanized 48 wk later. LV structure and function were assessed by serial echocardiography before and at 48 h and 4, 8, 16, 32, and 48 wk after MI. During follow-up, mice in group I exhibited worsening of LV function and progressive LV remodeling. Compared with group I, both groups II and III exhibited improved LV EF at 4 wk after MI; however, only in group II was this improvement sustained at 48 wk. Group II was also the only group in which the decrease in infarct wall thickening fraction, the LV dilatation, and the increase in LV mass were attenuated vs. group I. We conclude that the beneficial effect of G-CSF+FL on postinfarction LV dysfunction and remodeling is sustained for at least 11 months, and thus is likely to be permanent. In contrast, the effect of G-CSF+SCF was not sustained beyond the first few weeks, and G-CSF alone is ineffective. To our knowledge, this is the first long-term study of cytokines in postinfarction LV remodeling. The results reveal heretofore unknown differential actions of cytokines and have important translational implications.

Post coital hemoptysis.

Ischemic mitral regurgitation is a complication of coronary artery disease specifically in the settings of prior myocardial infarction. It is a dynamic lesion and its severity may increase with different forms of exercise leading to flash pulmonary edema. We present the case of an 81-year-old man with ischemic mitral regurgitation who presented with long standing history of hemoptysis limited to sexual intercourse only. After a thorough negative work-up for the usual causes of hemoptysis, comprehensive right and left cardiac catheterization studies revealed marked increase in baseline mitral regurgitation and pulmonary capillary wedge pressure with isometric exercise. This case illustrates that sexual intercourse, a form of isometric exercise, can cause severe increase in ischemic mitral regurgitation and more so compared to other forms of exercise due to heightened sympathetic activity, leading to flash pulmonary edema and hemoptysis.

The role of TNF-alpha receptors p55 and p75 in acute myocardial ischemia/reperfusion injury and late preconditioning.

The specific role of TNF-alpha receptors I (TNFR-I, p55) and II (TNFR-II, p75) in myocardial ischemic injury remains unclear. Using genetically engineered mice, we examined the relative effects of TNF-alpha signaling via p55 and p75 in acute myocardial ischemia/reperfusion injury under basal conditions and in late preconditioning (PC). Wild-type (WT) (C57BL/6 and B6,129) mice and mice lacking TNF-alpha (TNF-alpha(-/-)), p55 (p55(-/-)), p75 (p75(-/-)), or both receptors (p55(-/-)/p75(-/-)) underwent 30 min of coronary occlusion and 24 h of reperfusion with or without six cycles of 4-min coronary occlusion/4-min reperfusion (O/R) 24 h earlier (ischemic PC). Six cycles of O/R reduced infarct size 24 h later in WT mice, indicating a late PC effect. This late PC-induced infarct-sparing effect was abolished not only in TNF-alpha(-/-) and p55(-/-)/p75(-/-) mice, but also in p55(-/-) and p75(-/-) mice, indicating that TNF-alpha signaling via both p55 and p75 is necessary for the development of protection. In nonpreconditioned TNF-alpha(-/-), p55(-/-)/p75(-/-), and p75(-/-) mice, infarct size was similar to strain-matched WT mice. In contrast, infarct size in nonpreconditioned p55(-/-) mice was reduced compared with nonpreconditioned WT mice. We conclude that (i) unopposed p75 signaling (in the absence of p55) reduces infarct size following acute ischemia/reperfusion injury in naive myocardium, whereas unopposed p55 signaling (in the absence of p75) has no effect; and (ii) the development of the infarct-sparing effects of the late phase of PC requires nonredundant signaling via both p55 and p75 receptors. These findings reveal a fundamental, heretofore unrecognized, difference between the two TNF-alpha receptors in the setting of myocardial ischemia/reperfusion injury: that is, both p55 and p75 are necessary for the development of protection during late PC, but only signaling via p75 is protective in nonpreconditioned myocardium.

TGF-beta1 enhances cardiomyogenic differentiation of skeletal muscle-derived adult primitive cells.

The optimal medium for cardiac differentiation of adult primitive cells remains to be established. We quantitatively compared the efficacy of IGF-1, dynorphin B, insulin, oxytocin, bFGF, and TGF-beta1 in inducing cardiomyogenic differentiation. Adult mouse skeletal muscle-derived Sca1+/CD45-/c-kit-/Thy-1+ (SM+) and Sca1-/CD45-/c-kit-/Thy-1+ (SM-) cells were cultured in basic medium (BM; DMEM, FBS, IGF-1, dynorphin B) alone and BM supplemented with insulin, oxytocin, bFGF, or TGF-beta1. Cardiac differentiation was evaluated by the expression of cardiac-specific markers at the mRNA (qRT-PCR) and protein (immunocytochemistry) levels. BM+TGF-beta1 upregulated mRNA expression of Nkx2.5 and GATA-4 after 4 days and Myl2 after 9 days. After 30 days, BM+TGF-beta1 induced the greatest extent of cardiac differentiation (by morphology and expression of cardiac markers) in SM- cells. We conclude that TGF-beta1 enhances cardiomyogenic differentiation in skeletal muscle-derived adult primitive cells. This strategy may be utilized to induce cardiac differentiation as well as to examine the cardiomyogenic potential of adult tissue-derived stem/progenitor cells.

Transplantation of bone marrow-derived very small embryonic-like stem cells attenuates left ventricular dysfunction and remodeling after myocardial infarction.

Adult bone marrow (BM) contains Sca-1+/Lin-/CD45- very small embryonic-like stem cells (VSELs) that express markers of several lineages, including cardiac markers, and differentiate into cardiomyocytes in vitro. We examined whether BM-derived VSELs promote myocardial repair after a reperfused myocardial infarction (MI). Mice underwent a 30-minute coronary occlusion followed by reperfusion and received intramyocardial injection of vehicle (n= 11), 1 x 10(5) Sca-1+/Lin-/CD45+ enhanced green fluorescent protein (EGFP)-labeled hematopoietic stem cells (n= 13 [cell control group]), or 1 x 10(4) Sca-1+/Lin-/CD45- EGFP-labeled cells (n= 14 [VSEL-treated group]) at 48 hours after MI. At 35 days after MI, VSEL-treated mice exhibited improved global and regional left ventricular (LV) systolic function (echocardiography) and attenuated myocyte hypertrophy in surviving tissue (histology and echocardiography) compared with vehicle-treated controls. In contrast, transplantation of Sca-1+/Lin-/CD45+ cells failed to confer any functional or structural benefits. Scattered EGFP+ myocytes and capillaries were present in the infarct region in VSEL-treated mice, but their numbers were very small. These results indicate that transplantation of a relatively small number of CD45- VSELs is sufficient to improve LV function and alleviate myocyte hypertrophy after MI, supporting the potential therapeutic utility of these cells for cardiac repair. Disclosure of potential conflicts of interest is found at the end of this article.

Effects of anesthesia on echocardiographic assessment of left ventricular structure and function in rats.

Echocardiography is an essential diagnostic tool for accurate noninvasive assessment of cardiac structure and function in vivo. However, the use of anesthetic agents during echocardiographic studies is associated with alterations in cardiac anatomical and functional parameters. We sought to systematically compare the effects of three commonly used anesthetic agents on echocardiographic measurements of left ventricular (LV) systolic and diastolic function, LV dimensions, and LV mass in rats. Adult male Fischer 344 rats underwent echocardiographic studies under pentobarbital (PB, 25 mg/kg i.p.) (group I, n = 25), inhaled isoflurane (ISF, 1.5%) (group II, n = 25),or ketamine/xylazine (K/X, 37 mg/kg ketamine and 7 mg/kg xylazine i.p.) (group III, n = 25) anesthesia in a cross-over design. Echocardiography was also performed in an additional group of unanesthetized conscious rats (group IV, n = 5). Postmortem studies were performed to validate echocardiographic assessment of LV dimension and mass. Rats in group I exhibited significantly higher LV ejection fraction, fractional shortening, fractional area change, velocity of circumferential fiber shortening corrected for heart rate, and heart rate as compared with groups II and III. LV end-diastolic volume, end-diastolic diameter, and cross-sectional area in diastole were significantly smaller in group I compared with groups II and III. Cardiac output was significantly lower in group III compared with groups I and II. Postmortem LV mass measurements correlated well with echocardiographic estimation of LV mass for all anesthetic agents, and the correlation was best with PB anesthesia. Limited echocardiographic data obtained in conscious rats were similar to those obtained under PB anesthesia. We conclude that compared with ISF and K/X anesthesia, PB anesthesia at a lower dose yields echocardiographic LV structural and functional data similar to those obtained in conscious rats. In addition, PB anesthesia also facilitates more accurate estimation of LV mass.

Sca-1 expression is associated with decreased cardiomyogenic differentiation potential of skeletal muscle-derived adult primitive cells.

Adult stem cells from skeletal muscle (SM) have been shown to differentiate into multiple lineages. The impact of stem cell antigen-1 (Sca-1) expression on cardiomyogenic differentiation potential of SM-derived primitive cells remains unknown. Cardiomyogenic differentiation was induced in freshly isolated or culture-expanded Sca-1+/CD45-/c-kit-/Thy-1+ (SM+) and Sca1-/CD45-/c-kit-/Thy-1+ (SM-) cells isolated from SM of C57BL/6 mice. Expression of mRNA of cardiac-specific antigens and those associated with pluripotency was examined by real-time RT-PCR. Phenotypic analysis of expanded cells was performed during each passage by flow cytometry. Cardiomyocytic differentiation in vitro was verified by morphologic analysis, immunocytochemistry, and contractile properties. In freshly isolated cells, compared with unfractionated SM-derived cells as well as SM+ cells, mRNA expression of cardiac-specific antigens and those associated with cellular pluripotency was greater in SM- cells. Compared with SM- cells, SM+ cells exhibited greater expansion capacity. Freshly isolated SM- cells exhibited greater cardiac differentiation potential compared with freshly isolated SM+ cells (21.8+/-0.3% of SM- cells positive for cardiac markers vs. 9.1+/-0.7% of SM+ cells, P=0.00009). Differentiated SM- cells acquired a cardiomyocytic phenotype and exhibited spontaneous rhythmic contractions in vitro. The number of Sca-1+ cells in the SM- population increased markedly with time (0.9+/-0.1% in freshly isolated cells vs. 11.9+/-0.9% after the first passage vs. 99.0+/-0.6% after the second passage). This increase in Sca-1 expression was associated with a marked decline in the expression of cardiac markers following differentiation induction in culture-expanded SM- cells (21.8+/-0.3% in unexpanded cells vs. 16.6+/-1.3% after the first passage vs. 6.0+/-0.5% after the second passage, P=0.00001 vs. unexpanded cells). In contrast, the SM+ cells did not exhibit any consistent pattern in either phenotypic or differentiation capability with expansion. We conclude that SM- cells are inherently predisposed to undergo cardiac differentiation and are enriched in markers of pluripotency. While both Sca-1+ and Sca-1- primitive cells from SM can undergo cardiac differentiation, Sca-1- cells exhibit greater cardiomyogenic potential, and the appearance of Sca-1 during expansion is associated with a decline in cardiac differentiation plasticity.

Factors affecting the outcome of acute renal failure among the elderly population in India: a hospital based study.

The spectrum of acute renal failure (ARF) in the elderly population and the factors predicting poor outcome in these patients are not well defined in literature. Identification of risk factors and poor prognostic markers in these patients can help in planning strategies to prevent ARF and to prioritise the utilization of sparse and expensive therapeutic modalities, especially in a developing country like ours. We retrospectively analyzed data of 454 elderly patients (age >or=60 years), detected having ARF in a tertiary care super-speciality hospital in North India, from April 2000 to March 2004. The mean age of this population was 66.4 years with 70.5% being male. 64% patients had more than one precipitating factors for ARF, with volume depletion being the most common precipitating factor (33% cases). Infection/sepsis (21.6%) and drugs (11.5%) were other important precipitating factors. 31.8% were recorded as having oliguric ARF (urine output <400 ml/day) and 33.5% required renal replacement therapy (RRT). Acute peritoneal dialysis was the most frequent form of RRT given (62.5%). Mortality was 41.2% (187 cases), of whom 56 (29.8%) died inspite of recovery from ARF. Among the survivors, 103 patients (22.7%) had complete renal recovery, 141 (31.1%) had partial renal recovery, while 23 (8.6%), remained dialysis dependent. The factors which were found to be associated with increased mortality were; age >or=70 years, presence of previous chronic illness, ARF precipitated by cardiac failure and infection, need for RRT, oliguria and increasing numbers of failed organs. To conclude, ARF among elderly is a common problem in nephrology practice at our institute and is responsible for 48.9% of nephrology admissions/consultations among elderly patients. Majority of these patients are prone to multiple renal insults. Underlying chronic illness, presence of cardiac failure and sepsis, oliguria, need for RRT and increasing number of organ failure is associated with poor outcome.