“Know Thy Body, Know Thyself: Decoding Knowledge of the Ātman in Sanskrit Medical Literature”

A study of mental disease in Cakrapāṇidatta's commentary on the Carakasaṃhitā

Development of Micromechanics Based Constitutive Model for Alumina Using Unified Mechanics Theory Role of Microcracks in Damage

Ceramic materials used in mechanical applications show variations in their properties due to the difference in the presence of cracks and various defects. The micro-crack length, orientation, geometry and wing crack formation and propagation within the ceramic material define the strength of the ceramic material. In this study, a micro-mechanics-based model that accounts for micro-cracks is developed. Unlike other micromechanics-based models, the current model defines failure based on entropy. Entropy generated with various micro-crack lengths, orientations and wing crack extensions is calculated using the energy approach.The Unified Mechanics Theory (UMT) is used to define the damage in the ceramic material, which can include all possible failure mechanisms. A representative volume element (RVE) with a pre-existing flaw is simulated to generate stress-strain curves. The effect of different initial crack lengths and orientations on alumina peak strength is also investigated

Detecting mycobacteraemia for diagnosing tuberculosis

Background & objectives: In human immunodeficiency virus (HIV) infected persons with pulmonary tuberculosis (TB), sputum may not always show acid fast bacilli (AFB). Moreover, in most cases of suspected extrapulmonary TB (irrespective of HIV status) mycobacteria-containing material is not readily available for investigation. This study evaluated whether blood culture for Mycobacterium tuberculosis bacteraemia (mycobacteraemia) help in diagnosing TB in such cases. Methods: A total of 93 consecutive subjects with a clinical diagnosis of tuberculosis with or without laboratory confirmation, 42 with and 38 without coexisting HIV infection, and 13 patients with HIV infection without clinical evidence of TB were enrolled. Mycobacterial blood cultures were done using lysis centrifugation technique followed by subculturing onto the modified Lowenstein-Jenson medium (LJ-1) and Selective Kirchner's medium followed by subculturing onto the modified Lowenstein- Jenson medium (LJ-2, LJ-3). Results: Of the 15 (16.2%) subjects with evidence of mycobacteremia in 4 (26.7%) blood was the first/ only source of diagnosing TB. Among 80 patients with clinical diagnosis of TB whether supported by laboratory tests or not, 14 (17.5%) had mycobacteraemia. Among the 21 HIV infected patients with laboratory proven TB, 9 (43%) had mycobacteraemia. Interpretation & conclusion: Blood culture appears to be a useful additional test to diagnose TB in personss with HIV infection. In patients without HIV infection, but with clinical picture compatible with TB, blood culture for mycobacteraemia may occasionally help in the diagnosis. We recommend the use of the lysis centrifugation technique followed by direct smear of the sediment along with inoculation of the sediment into both modified Lowenstein-Jenson medium and the Selective Kirchner's medium with subsequent subculturing onto the modified Lowenstein-Jenson medium for mycobacterial blood culture for detecting mycobacteraemia

Comparison of different culture media and storage temperatures for the long-term preservation of Streptococcus pneumoniae in the tropics

Objective: The preservation of Streptococcus pneumoniae by standard freezing methods for subsequent tests- such as serotyping and antibiotic susceptibility-is not possible or is difficult in many developing countries because of the high cost of equipment, inadequate equipment maintenance, and irregular power supply. We evaluated alternative low-cost methods, by comparing different culture media and storage temperatures. Methods: Clinical isolates of five capsular types (1, 5, 7, 19, and 23) of S. pneumoniae were preserved in rabbit blood, sheep blood, skimmed milk, or glycerol-chocolate broth, and stored at -20 °C or -70 °C. The cultures were also preserved by lyophilization or sand desiccation, followed by storage at room temperature and 4 °C. The viability of the preserved cultures was determined by making serial colony counts on day 0 and after 1 week, 4 weeks, 4 months and 16 months. The viability of cultures preserved by sand desiccation and storage at 4 °C was also determined every 6 months for up to 68 months. Findings: Irrespective of the media used, cultures maintained at -20 °C became nonviable by the fourth month, while those maintained at -70 °C were still viable at 16 months. Cultures preserved by lyophilization or sand desiccation lost their viability by the fourth month when maintained at local room temperature (30-42 °C), but remained viable when stored at 4 °C for up to 68 months. Conclusions: Our results confirm that freezing at -70 °C, or lyophilization and storage at 4 °C are the ideal methods for the preservation of S. pneumoniae. In laboratories where lyophilization is not feasible, sand desiccation and storage at 4 °C offers an alternative low-cost method for the long-term preservation of S. pneumoniae

Transmission dynamics of methicillin-resistant Staphylococcus aureus in a medical intensive care unit in India

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a global pathogen and an important but seldom investigated cause of morbidity and mortality in lower and middle-income countries where it can place a major burden on limited resources. Quantifying nosocomial transmission in resource-poor settings is difficult because molecular typing methods are prohibitively expensive. Mechanistic statistical models can overcome this problem with minimal cost. We analyse the transmission dynamics of MRSA in a hospital in south India using one such approach and provide conservative estimates of the organism's economic burden. Methods and Findings: Fifty months of MRSA infection data were collected retrospectively from a Medical Intensive Care Unit (MICU) in a tertiary hospital in Vellore, south India. Data were analysed using a previously described structured hidden Markov model. Seventy-two patients developed MRSA infections and, of these, 49 (68%) died in the MICU. We estimated that 4.2% (95%CI 1.0, 19.0) of patients were MRSA-positive when admitted, that there were 0.39 MRSA infections per colonized patient month (0.06, 0.73), and that the ward-level reproduction number for MRSA was 0.42 (0.08, 2.04). Anti-MRSA antibiotic treatment costs alone averaged $124/patient, over three times the monthly income of more than 40% of the Indian population. Conclusions: Our analysis of routine data provides the first estimate of the nosocomial transmission potential of MRSA in India. The high levels of transmission estimated underline the need for cost-effective interventions to reduce MRSA transmission in hospital settings in low and middle income countries

Region Specific and Worldwide Distribution of Collagen-Binding M Proteins with PARF Motifs among Human Pathogenic Streptococcal Isolates

Some of the variety of Streptococcus pyogenes and Streptococcus dysgalactiae ssp. equisimilis (SDSE) M proteins act as collagen-binding adhesins that facilitate acute infection. Moreover, their potential to trigger collagen autoimmunity has been implicated in the pathogenesis of acute rheumatic fever and attributed to a collagen-binding motif called PARF (peptide associated with rheumatic fever). For the first time we determine the rate of clinical isolates with collagen-binding M proteins that use a PARF motif (A/T/E)XYLXX(L/F)N in a defined geographic region, Vellore in South India. In this region both, incidence of streptococcal infections and prevalence of acute rheumatic fever are high. M proteins with PARF motif conferred collagen-binding activity to 3.9% of 153 S. pyogenes and 10.6% of 255 SDSE clinical isolates from Vellore. The PARF motif occurred in three S. pyogenes and 22 SDSE M protein types. In one of the S. pyogenes and five of the SDSE M proteins that contained the motif, collagen-binding was impaired, due to influences of other parts of the M protein molecule. The accumulated data on the collagen binding activity of certain M protein types allowed a reanalysis of published worldwide emm-typing data with the aim to estimate the rates of isolates that bind collagen via PARF. The results indicate that M proteins, which bind collagen via a PARF motif, are epidemiologically relevant in human infections, not only in Vellore. It is imperative to include the most relevant collagen-binding M types in vaccines. But when designing M protein based vaccines it should be considered that collagen binding motifs within the vaccine antigen remain potential risk factors

Contribution of Streptococcus anginosus to Infections Caused by Groups C and G Streptococci, Southern India

This neglected pathogen causes a large portion of these infections

Know Thy Body, Know Thyself: Decoding Knowledge of the Ātman in Sanskrit Medical Literature

This essay discusses a central assertion in the Caraka SaṃhitÄ about the origin of mental distress and the eleventh century commentator CakrapÄṇidatta\u27s interpretation of that assertion.  We argue that CakrapÄṇi\u27s reading of Caraka is dependent on the polythetic meaning of Ätman in classical India and classical indian medicine, and we suggest that CakrapÄṇi\u27s hermeneutical innovation is to claim that knowledge of oneself as a physical body is primary to, and indeed funadamental for, all other types of knowledge about one\u27s self as an embodied, transmigratory entity.   &nbsp

Brief Communication - Evaluation of simplified dna extraction methods for EMM typing of group a streptococci

Simplified methods of DNA extraction for amplification and sequencing for emm typing of group A streptococci (GAS) can save valuable time and cost in resource crunch situations. To evaluate this, we compared two methods of DNA extraction directly from colonies with the standard CDC cell lysate method for emm typing of 50 GAS strains isolated from children with pharyngitis and impetigo. For this, GAS colonies were transferred into two sets of PCR tubes. One set was preheated at 94°C for two minutes in the thermal cycler and cooled while the other set was frozen overnight at -20°C and then thawed before adding the PCR mix. For the cell lysate method, cells were treated with mutanolysin and hyaluronidase before heating at 100°C for 10 minutes and cooling immediately as recommended in the CDC method. All 50 strains could be typed by sequencing the hyper variable region of the emm gene after amplification. The quality of sequences and the emm types identified were also identical. Our study shows that the two simplified DNA extraction methods directly from colonies can conveniently be used for typing a large number of GAS strains easily in relatively short time