Current Place of SGLT2i in the Management of Heart Failure: An Expert Opinion from India.

Heart failure (HF) is a global health concern that is prevalent in India as well. HF is reported at a younger age in Indian patients with comorbidity of type 2 diabetes (T2DM) in approximately 50% of patients. Sodium-glucose cotransporter-2 inhibitors (SGLT2i), originally approved for T2DM, are new guideline-recommended and approved treatment strategies for HF. Extensive evidence highlights that SGLT2i exhibits profound cardiovascular (CV) benefits beyond glycemic control. SGLT2i, in conjunction with other guideline-directed medical therapies (GMDT), has additive effects in improving heart function and reducing adverse HF outcomes. The benefits of SGLT2i are across a spectrum of patients, with and without diabetes, suggesting their potential place in broader HF populations irrespective of ejection fraction (EF). This consensus builds on the updated evidence of the efficacy and safety of SGLT2i in HF and recommends its place in therapy with a focus on Indian patients with HF.

Consensus Statement from India on the Renal Benefits of ARNi, SGLT-2i, and Bisoprolol in Chronic Kidney Disease.

Chronic kidney disease (CKD) is a major contributor to morbidity and mortality in India. CKD often coexists with heart failure (HF), diabetes, and hypertension. All these comorbidities are risk factors for renal impairment. HF and CKD are pathophysiologically intertwined, and the deterioration of one can worsen the prognosis of the other. There is a need for safe renal pharmacological therapies that target both CKD and HF and are also useful in hypertension and diabetes. Neurohormonal activation achieved through the activation of the sympathetic nervous system (SNS), the renin-angiotensin-aldosterone system (RAAS), and the natriuretic peptide system (NPS) is fundamental in the pathogenesis and progression of CKD and HF. Angiotensin receptor neprilysin inhibitor (ARNi), sodium-glucose cotransporter 2 inhibitors (SGLT-2i), and selective ß1-blocker (B1B) bisoprolol suppress this neurohormonal activation. They also have many other cardiorenal benefits across a wide range of CKD patients with or without concomitant HF, diabetes, or hypertension. This consensus statement from India explores the place of ARNi, SGLT-2i, and bisoprolol in the management of CKD patients with or without HF and other comorbidities.

The Power and Promise of Angiotensin Receptor Neprilysin Inhibitor (ARNI) in Heart Failure Management: National Consensus Statement.

;Heart failure (HF) is a huge global public health task due to morbidity, mortality, disturbed quality of life, and major economic burden. It is an area of active research and newer treatment strategies are evolving. Recently angiotensin receptor-neprilysin inhibitor (ARNI), a class of drugs (the first agent in this class, Sacubitril-Valsartan), reduces cardiovascular mortality and morbidity in chronic HF patients with reduced left ventricular ejection fraction (LVEF). Positive therapeutic effects have led to a decrease in cardiovascular mortality and HF hospitalizations (HFH), with a favorable safety profile, and have been documented in several clinical studies with an unquestionable survival benefit with ARNI, Sacubitril-Valsartan. This consensus statement of the Indian group of experts in cardiology, nephrology, and diabetes provides a comprehensive review of the power and promise of ARNI in HF management and an evidence-based appraisal of the use of ARNI as an essential treatment strategy for HF patients in clinical practice. Consensus in this review favors an early utility of Sacubitril-Valsartan in patients with HF with reduced EF (HFrEF), regardless of the previous therapy being given. A lower rate of hospitalizations for HF with Sacubitril-Valsartan in HF patients with preserved EF who are phenotypically heterogeneous suggests possible benefits of ARNI in patients having 40-50% of LVEF, frequent subtle systolic dysfunction, and higher hospitalization risk.

Role of Iron Therapy in Heart Failure: A Consensus Statement from India.

Iron deficiency (ID) with or without anemia is frequently observed in patients with heart failure (HF). Uncorrected ID is associated with higher hospitalization and mortality in patients with acute HF (AHF) and chronic HF (CHF). Hence, in addition to chronic renal insufficiency, anemia, and diabetes, ID appears as a novel comorbidity and a treatment target of CHF. Intravenous (IV) ferric carboxymaltose (FCM) reduces the hospitalization risk due to HF worsening and improves functional capacity and quality of life (QOL) in HF patients. The current consensus document provides criteria, an expert opinion on the diagnosis of ID in HF, patient profiles for IV FCM, and correct administration and monitoring of such patients.

Angiotensin Receptor-Neprilysin Inhibitor Therapy and Cardiac Remodeling in Heart Failure: Consensus Statement from India.

Adverse cardiac remodeling refers to progressive structural and functional modifications in the heart because of increased wall stress in the myocardium, loss of viable myocardium, and neurohormonal stimulation. The guideline-directed medical therapy for Heart failure (HF) includes Angiotensin receptor-neprilysin inhibitor (ARNI) (sacubitril/valsartan), ß-blockers, sodium-glucose co-transporter 2 (SGLT2) inhibitors, and mineralocorticoid receptor antagonists (MRA). ARNI is under-prescribed in India despite its attractive safety and efficacy profile. Therefore, the consensus discusses objectives and topics related to ARNI in the management of cardiac remodeling, and experts shared their views on the early timely intervention of effective dosage of ARNI to improve the diagnosis and enhance mortality and morbidity benefits in cardiac reverse remodeling (CRR).

Role of Bisoprolol in Heart Failure Management: A Consensus Statement from India.

In India, heart failure (HF) is an important health concern affecting younger age groups than the western population. A limited number of Indian patients receive guideline-directed medical therapy (GDMT). Selective ß-1 blockers (BB) are one of the GDMTs in HF and play an important role by decreasing the sympathetic overdrive. The BB reduces heart rate (HR) reverse the adverse cardiac (both ventricular and atrial), vascular, and renovascular remodeling seen in HF. Bisoprolol, a ß-1 blocker, has several advantages and can be used across a wide spectrum of HF presentations and in patients with HF and comorbid conditions such as coronary artery disease (CAD), atrial fibrillation (AF), post-myocardial infarction (MI), uncontrolled diabetes, uncontrolled hypertension, and renal impairment. Despite its advantages, bisoprolol is not optimally utilized for managing HF in India. This consensus builds on updated evidence on the efficacy and safety of bisoprolol in HF and recommends its place in therapy with a focus on Indian patients with HF.

Rheumatic Heart Disease in India in 2020: Advances in Diagnostic and Therapeutic Options.

Rheumatic Fever (RF)/ Rheumatic Heart Disease (RHD) is the result of autoimmune response triggered by group A Beta-haemolytic streptococcal pharyngitis leading to immune-inflammatory injury to cardiac valves. It is practically disappeared in developed countries. However, it continues to be a major cause of disease burden among children, adolescents, and young adults in low-income countries and even in high-income countries with socioeconomic inequalities. For decades, many cases of Acute Rheumatic Fever (ARF) and RHD were missed and were denied the secondary prophylaxis, as a result these patients used to end up with complications and untimely death. Advanced understanding of the echocardiography can prevent both under diagnosis and over diagnosis and thus help in management strategy. Another new advancement in recent past is the mitral valve repair, which is technically demanding, and the results are acceptable in experienced cardiac surgical units. Whenever feasible, valve repair should be preferred over valve replacement since it precludes the need for anticoagulation and future risks of prosthesis dysfunction.

COVID-Inflicted Coagulopathy: Expert Consensus on Management with Novel Oral Anticoagulants in India.

Coronavirus disease 2019 (COVID-19) is a highly hypercoagulable viral infection complicated as COVID-inflicted coagulopathy (CIC), that is associated with increased risk of morbidity and mortality. International guidelines recommend low molecular weight heparin (LMWH) to treat CIC in both in-hospital and in-home settings. However, in India, using subcutaneous LMWH may not be a feasible option for a vast majority of patients under home management. Additionally, while some evidence advocates the use of novel oral anticoagulants (NOACs), in hospitalized settings, most guidelines find no role of NOACs in hospital settings. On the other hand, the resource crunch faced in recent COVID-19 pandemic in India forced physicians to treat many patients in home settings. These patients had been usually prescribed NOACs for ease of administration and adherence. Therefore, there is a need to form a consensus on the use of NOACs to manage CIC in India.

Lapine periodontal ligament stem cells for musculoskeletal research in preclinical animal trials.

BACKGROUND: Human periodontal ligament stem cells (hPDLSCs) have been shown to be a reliable source of mesenchymal stem cells (MSCs). On the other hand, rabbits have been commonly used in preclinical trials for musculoskeletal research. However, there is a lack of sufficient data on using rabbit periodontal ligament stem cells (rPDLSCs) for regenerative dentistry. This study, for the first time, comprehensively compared rPDLSCs against hPDLSCs in terms of clonogenicity, growth potential, multi-differential capacity and surface antigens. METHODS: Periodontal ligament (PDL) was obtained from the rabbit and human teeth. rPDL and hPDL cells were isolated from PDL using enzymatic digestion method. After culturing for 2 weeks, the cells were first analyzed microscopically. STRO-1+CD146+ PDLSCs were then sorted from PDL cells by fluorescence-activated cell sorting (FACS) followed by examination of CD34, CD45, CD90, vimentin and desmin markers. The cells were also evaluated by immunohistocytochemical and multi-differentiation potential tests. The clonogenicity and growth of PDL cells were analyzed by Independent T test and 2-way repeated measures ANOVA respectively. RESULTS: rPDL cells were broader and less elongated as compared to hPDL cells. STRO-1+CD146+ hPDLSCs were isolated from hPDL cells but not from the rPDL cells. Therefore, heterogeneous population of rabbit and human PDL cells were subsequently used for latter comparative studies. FACS analysis and immunohistocytochemistry revealed that rPDL cells were partially positive for STRO-1 as compared to hPDL cells. Furthermore, both rPDL cells and hPDL cells were positive for CD146, CD90, vimentin, and desmin, while negative for CD34 and CD45. No difference in clonogenicity between rPDL and hPDL cells was found (p > 0.05). The proliferative potential of rPDL cells displayed significantly slower growth as compared to hPDL cells (p < 0.05). Osteogenic, adipogenic, and chondrogenic differentiation potential was comparatively less in rPDL cells than that of hPDL cells, but the neurogenic differential potential was similar. CONCLUSION: Although rPDL cells manifested variable differences in expression of stem cell markers and multi-differential potential as compared to hPDL cells, they demonstrated the attributes of stemness. Further studies are also required to validate if the regenerative potential of rPDL cells is similar to rPDLSCs.

Comparative study on conventional, ultrasonication and microwave assisted extraction of γ-oryzanol from rice bran.

In present study, conventional, ultrasonic and microwave assisted extraction methods were compared with the aim of optimizing best fitting solvent and method, solvent concentration and digestion time for high yield of γ-oryzanol from rice bran. Petroleum ether, hexane and methanol were used to prepare extracts. Extraction yield were evaluated for giving high crude oil yield, total phenolic content (TPC) and γ-oryzanol content. Gas chromatography-mass spectrophotometry was used for the determination of γ-oryzanol concentration. The highest concentration of γ-oryzanol was detected in methanolic extracts of microwave treatment (85.0 ppm) followed by ultrasonication (82.0 ppm) and conventional extraction method (73.5 ppm). Concentration of γ-oryzanol present in the extracts was found to be directly proportional to the total phenolic content. A combination of 80 % methanolic concentration and 55 minutes digestion time of microwave treatment yielded the best extraction method for TPC and thus γ-oryzanol (105 ppm).

Injectable Tissue-Specific Hydrogel System for Pulp-Dentin Regeneration.

The quest for finding a suitable scaffold system that supports cell survival and function and, ultimately, the regeneration of the pulp-dentin complex remains challenging. Herein, we hypothesized that dental pulp stem cells (DPSCs) encapsulated in a collagen-based hydrogel with varying stiffness would regenerate functional dental pulp and dentin when concentrically injected into the tooth slices. Collagen hydrogels with concentrations of 3 mg/mL (Col3) and 10 mg/mL (Col10) were prepared, and their stiffness and microstructure were assessed using a rheometer and scanning electron microscopy, respectively. DPSCs were then encapsulated in the hydrogels, and their viability and differentiation capacity toward endothelial and odontogenic lineages were evaluated using live/dead assay and quantitative real-time polymerase chain reaction. For in vivo experiments, DPSC-encapsulated collagen hydrogels with different stiffness, with or without growth factors, were injected into pulp chambers of dentin tooth slices and implanted subcutaneously in severe combined immunodeficient (SCID) mice. Specifically, vascular endothelial growth factor (VEGF [50 ng/mL]) was loaded into Col3 and bone morphogenetic protein (BMP2 [50 ng/mL]) into Col10. Pulp-dentin regeneration was evaluated by histological and immunofluorescence staining. Data were analyzed using 1-way or 2-way analysis of variance accordingly (α = 0.05). Rheology and microscopy data revealed that Col10 had a stiffness of 8,142 Pa with a more condensed and less porous structure, whereas Col3 had a stiffness of 735 Pa with a loose microstructure. Furthermore, both Col3 and Col10 supported DPSCs' survival. Quantitative polymerase chain reaction showed Col3 promoted significantly higher von Willebrand factor (VWF) and CD31 expression after 7 and 14 d under endothelial differentiation conditions (P < 0.05), whereas Col10 enhanced the expression of dentin sialophosphoprotein (DSPP), alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), and collagen 1 (Col1) after 7, 14, and 21 d of odontogenic differentiation (P < 0.05). Hematoxylin and eosin and immunofluorescence (CD31 and vWF) staining revealed Col10+Col3+DPSCs+GFs enhanced pulp-dentin tissue regeneration. In conclusion, the collagen-based concentric construct modified by growth factors guided the specific lineage differentiation of DPSCs and promoted pulp-dentin tissue regeneration in vivo.

Treatment practices in pulmonary tuberculosis by private sector physicians of Meerut, Uttar Pradesh.

BACKGROUND: Majority of the qualified medical practitioners in the country are in the private sector and more than half of patients with tuberculosis (TB) seek treatment from them. The present study was conducted with the objective of assessing the treatment modalities in pulmonary tuberculosis by the private physicians in Meerut City, Uttar Pradesh, India. METHODS: A cross-sectional study was carried out covering all the private physicians (graduates and postgraduates in Medicine and Chest Diseases) registered under the Indian Medical Association, Meerut Branch (n = 154). The physicians were interviewed by a pre-designed and pre-tested questionnaire about the treatment modalities practiced by them. RESULTS: Only 43.5% private physicians had attended any Revised National Tuberculosis Control Programme (RNTCP) training in the past five years. Only 33.1% of them were aware of the International Standards of Tuberculosis Care (ISTC). Fifty-three different regimens were used to treat the patients. Majority of physicians (76%) prescribed daily regimens while 24% administered both daily and intermittent treatment. None of the private physicians prescribed exclusive intermittent regimen. Eighty-seven different treatment regimens were used for the treatment of multidrug-resistant TB (MDR-TB) with none of them prescribing standard treatment under RNTCP. CONCLUSION: As majority of private practitioners do not follow RNTCP guidelines for treating TB, there is an urgent need for their continued education in this area.

HIF-1α Stabilization Boosts Pulp Regeneration by Modulating Cell Metabolism.

Stem cell-based therapeutics is a promising strategy in dental pulp regeneration. However, low cell viability after transplantation in vivo due to the ischemic microenvironment is still a critical challenge for future clinical application. With the aim of improving postimplantation cell survival and pulp tissue regeneration, stem cells from human exfoliated deciduous teeth (SHED) were preconditioned to a hypoxic condition by hypoxia-inducible factor 1α (HIF-1α) stabilization via knockdown of prolyl hydroxylase domain-containing protein 2 (PHD2) using lentiviral short hairpin RNA. HIF-1α-stabilized SHED were encapsulated in PuraMatrix hydrogel, injected into root canals of human tooth fragments, and implanted in the subcutaneous space of immunodeficient mice. After 28 d, enhanced dental pulp-like tissue formation was observed with a significantly higher level of vascularization, which could be attributed to both endothelial differentiation of SHED and recruitment of host blood vessels. Furthermore, dentin-like tissue formation in vivo and accelerated odontogenic/osteogenic differentiation both in vivo and in vitro were observed. At 7 d postimplantation, significantly less DNA damage and higher Ki67 expression were detected in the HIF-1α-stabilized SHED group compared with the control SHED. Accordingly, cell viability assay and staining for Ki67 and apoptotic cells in vitro showed that HIF-1α stabilization could decrease cell apoptosis and enhance cell survival significantly. We demonstrated that PI3K/AKT pathway activation had resulted in low caspase 3 expression in HIF-1α-stabilized SHED in hypoxic conditions. Furthermore, we found that HIF-1α-induced cell survival could also be attributed to the upregulated expression of PDK1, HK2, and Glut1, which contributes to the maintenance of reactive oxygen species homeostasis and metabolic adaptation in hypoxia. In addition, we identified Smad7 as 1 of the top 3 upregulated genes through RNA sequencing in HIF-1α-stabilized SHED and demonstrated its essential role in HK2 and Glut1 upregulation. Taken together, HIF-1α stabilization enhances cell survival of SHED through modulating various target genes and potential signaling pathways, as well as odontogenic tissue formation during dental pulp regeneration, which could benefit stem cell-based therapy in general.

Techniques to assess myocardial viability.

Assessment of myocardial viability in patients with chronic coronary artery disease or acute and sub-acute myocardial infarction is clinically important for distinguishing stunned and hibernating myocardium from irreversibly injured myocardium. Patients may benefit from revascularization when viable tissue is present in the dysfunctional area of the myocardium. Several clinical imaging modalities exist for assessment of viable myocardium which have proven useful for chronic chronic coronary artery disease are available but a reliable technique for the assessment of myocardial viability in the sub-acute situation does not exist.

Patterns of left ventricular hypertrophy in chronic kidney disease: an echocardiographic evaluation.

BACKGROUND: We evaluated the chronic kidney disease (CKD) patients having different degree of uremia for the prevalence of Left Ventricular Hypertrophy (LVH), different patterns of left Ventricular Hypertrophy by echocardiographic variables to define the most sensitive and powerful predictor of cardiovascular disease (CVD) and premature morbidity and mortality. METHODS: We used clinical and biochemical data from the prospective study done by us to evaluate "The Echocardiographic assessment of cardiac functions in patients with chronic kidney disease". The diagnosis of CKD was made on the basis of serum creatinine (sCr) concentration of more than 1.5 mg/dl, persistent and with no evidence of recovery over a period of 3 months. Glomerular filtration rate (GFR) was calculated by the Modification of Diet in Renal Disease (MDRD) equation and cut-off for CKD was taken to be < 60 ml/min/1.73 m2 as per existing guidelines. The study population consisted of a total of 75 subjects divided into three groups of 25 subjects each, all between the age of 20-65 yrs: GROUP A: Healthy normal controls (sCr < 1.5 mg/dl); GROUP B: Patients with mild to moderate CKD (sCr 1.5 - 6.0 mg/dl); GROUP C: Patients with severe CKD (sCr > 6.0 mg/dl). RESULTS: A progressive rise in prevalence of LVH was observed with the severity of kidney disease from 64% (mild/ moderate CKD group) to 96% (severe CKD group) and higher prevalence of LVH in females than males in the severe CKD group. The mean LVMI in both the groups of CKD was significantly higher than the healthy controls (76.62 +/- 10.97). Also, mean LVMI in severe CKD (139.23 +/- 17.47) patients was significantly higher than in mild/moderate CKD (114.91 +/- 15.20) patients. The prevalence of concentric remodeling in both the CKD groups was alike (20%). While that of concentric hypertrophy in severe CKD patients (68%) was significantly higher than in mild/moderate CKD group (40%) (p < 0.05), but no significant difference was observed for eccentric pattern of hypertrophy between the two CKD groups. This suggests that concentric hypertrophy is more prevalent in CKD patients. CONCLUSIONS: The mean left ventricular mass index (LVMI) showed a proportionate increase with the severity of renal failure and a progressive rise with increase in severity of disease. Patients of CKD groups revealed occurrence of concentric remodeling which is a predictor of high vulnerability for progressing into concentric and eccentric hypertrophy. Hence early medical intervention may reverse the concentric remodeling, thereby preventing the advancement to concentric or eccentric LVH.

Enhanced external counterpulsation and CVD protection: 3D echo validation: a promising approach.

UNLABELLED: AIMS & OBJECTIVE: To evaluate the impact of enhanced external counterpulsation (EECP) on various echo variables by 3D-Echocardiography. MATERIALS AND METHODS: 60 adult patients from indoor and outdoor patient department; consisting of 16 patients with heart failure (HF) with left ventricular systolic dysfunction, 20 patients with heart failure with normal ejection fraction (HFNEF), 4 patients with prior percutaneous coronary intervention (PCI), 3 patients with prior coronary artery bypass grafting (CABG) and 17 patients with syndrome X; were subjected to Echocardiographic evaluation. The various echo variables included were left ventricular myocardial performance index (LVMPI), left ventricular mass index (LVMi), left ventricular diastolic dysfunction (LVDD), left ventricular systolic function (LVEF) and left atrial volume index (LAVi). Once randomized, patients underwent 35 hrs EECP treatment sessions, each lasting 1 hour, could be given once or twice per day. RESULTS: There was a significant reduction in the overall prolonged mean LVMPI from baseline (0.54 +/- 0.2) to post ECP treatment (0.43 +/- 0.1) in the total study population (p < 0.001). EECP treatment significantly reduced baseline grade II or grade III diastolic dysfunction and E/E' ratio > 12, but not in patients with baseline E/E' < 12, baseline normal diastolic function or grade I diastolic dysfunction. Similiarly the mean LVEF in the subset of patients with HF treatment was 30.7 +/- 3.1; post ECP the mean LVEF was increased to 36.9 +/- 3.2 which was statistically significant (p < 0.001). In the remaining patients, who had mean LVEF within normal range, there was no significant difference pre and post EECP (p value- NS). Pre EECP the mean LAVi in the total population was increased up to 33.4 +/- 5.6 ml/m2. Post EECP the mean LAVi reduced to 24.8 +/- 4.2 ml/m2, which was also statistically significant (p < 0.001). Regarding mean LVMi as well as in the patterns of LVH, there were no significant changes seen as compared to baseline. CONCLUSION: Enhanced External counterpulsation is noninvasive, non-surgical method of choice for CVD & heart failure protection. It is very useful in Single vessel or multivessel disease, heart failure, HFNEF, Post PCI or post CABG and syndrome X. It reduces LVMPI and improves global cardiac function, increases LVEF in patients with ejection fraction of less than 50%, reduces grade II or grade III diastolic dysfunction and E/E' ratio more than 12, decreases LAVi by 25.7%; thereby reducing adverse clinical events in CAD and heart failure.

Regression of coronary atherosclerosis through healthy lifestyle in coronary artery disease patients--Mount Abu Open Heart Trial.

AIMS: To evaluate the efficacy of a unique healthy and happy lifestyle (HLS) program in regression of coronary atherosclerosis and reduction in cardiac events in an open trial. METHODS: One hundred and twenty three angiographically documented moderate to severe coronary artery disease (CAD) patients were administered HLS comprising of low-fat, high-fiber vegetarian diet, moderate aerobic exercise and stress-management through Rajyoga meditation. Its most salient feature was training in self-responsibility (heal+thy) and self-empowerment through inner-self consciousness (swasth; swa=innerself, sth=consciousness) approach using Rajyoga meditation. Following a seven day in-house sojourn, patients were invited for six month follow-up for reassessment and advanced training. At the end of two years, all patients were asked to undergo repeat angiography. RESULTS: Three hundred and sixty coronary lesions were analysed by two independent angiographers. In CAD patients with most adherence, percent diameter stenosis regressed by 18.23 +/- 12.04 absolute percentage points. 91% patients showed a trend towards regression and 51.4% lesions regressed by more than 10 absolute percentage points. The cardiac events in coronary artery disease patients were: 11 in most adherence, and 38 in least adherence over a follow-up period of 6.48 yrs. (risk ratio; most vs least adherence: 4.32; 95% CI: 1.69-11.705; P < 0.002). CONCLUSION: Overall healthy changes in cardiovascular, metabolic and psychological parameters, decline in absolute percent diameter coronary stenosis and cardiac events in patients of CAD were closely related to HLS adherence. However, more than 50% adherence is essential to achieve a significant change.

Human sarcomas in culture. Foci of altered cells and a common antigen; induction of foci and antigen in human fibroblast cultures by filtrates.

In a study of human sarcomas maintained in culture for periods up to two years, the following observations were made. The most prominent cell type in serially cultured osteosarcomas was fibroblastic in appearance. After 16-20 wk in culture some lines spontaneously developed foci of altered cells resembling the foci produced in monolayer cultures by oncogenic viruses. The presence of these foci in the sarcoma cultures was transient, and usually they did not reappear; but in one instance they recurred with a characteristic periodicity of several weeks. From one of the sarcoma lines, in which foci appeared after 5 months in culture, two subcultures were established from stored frozen cells and these both exhibited foci after approximately the same lapse of time. The same phenomenon has been seen with another line, suggesting that the time of appearance of foci is characteristic for particular sarcomas. Foci of similar type could sometimes be induced in monolayer cultures of human fibroblasts by filtered medium from cultured sarcomas; this bore no relation to the presence or absence of foci in the sarcoma cultures at the time the filtrate was prepared. Electron microscopy of the spontaneous and induced foci, and of the sarcoma cultures, revealed no demonstrable virus. 12 out of 15 sarcoma cultures contained an antigen (S) demonstrable by indirect immunofluorescence with human sera. It was not present in any of the original sarcoma specimens, nor in any culture lines other than sarcomas. At least 3-4 wk in culture appear to be required for its demonstration. The antigen was cytoplasmic, occurred in only a small proportion of the cells, and was unpredictably variable in its expression, even in the same culture line. It could be induced in monolayer cultures of human fibroblasts by filtrates of medium from sarcoma cultures. As with the foci, the induction of S antigen in indicator cultures was not dependent upon the expression of antigen in the sarcoma line from which the filtrates were obtained. There was no association between the presence of foci and of antigen, nor was there any apparent relation between the ability of filtrates to induce foci and their ability to induce antigen. 80% or more of the general population have S antibody, and the titer of antibody in patients with sarcoma is no higher than in normal subjects. Thus, as in the case of Burkitt's lymphoma antigen, it appears that most individuals have been exposed to S antigen. But unlike Burkitt's lymphoma, no relation has so far been established between any particular disease and a corresponding high titer or frequency of occurrence of S antibody. The occurrence of foci of altered cells and of a common antigen, and the transmission of these two characters to indicator cells by filtrates, are all suggestive of a virus specifically associated with human sarcomas, one to which the general population is widely exposed, as indicated by the prevalence of antibody.