Dodecanoic acid & palmitic acid disarms rifampicin resistance by putatively targeting mycobacterial efflux pump Rv1218c.

Background & objectives: Drug-resistant tuberculosis (TB) jeopardizes the treatment process with poor outcomes. Efflux pumps (EPs) belonging to the ABC transporter family in Mycobacterium tuberculosis confer resistance to rifampicin (RMP) besides genetic mutations thus serving as a target for a potential adjunct therapeutic inhibitory molecule. Rv1218c is one such pump that was previously reported to be active in multidrug-resistant TB clinical isolates. Methods: In this study, the inhibition potential of Rv1218c-EP was tested on 8 molecules that were shortlisted by in silico methods. These molecules were subjected to the minimum inhibitory concentration (MIC) determination, checkerboard drug combination assay, ethidium bromide-DNA binding assay, and in vitro and ex vivo cytotoxicity assay. Results: Based on the outcome of the study, two molecules dodecanoic acid (DA) and palmitic acid (PA) were found to be potential enough to decrease the MIC of RMP by 8 to 1000 folds against multidrug-resistant clinical isolates and Rv1218c expressing recombinant Mycobacterium smegmatis. Interpretation & conclusions: These molecules were also found to reduce the time taken by RMP to kill these drug-resistant Mycobacteria to 48 h, unlike control isolates that survived more than 240 h of RMP exposure. The functional concentration of both molecules was non-toxic to the epithelial and blood mononuclear cells. With further comprehensive scientific validation, PA and DA could be recommended as adjunct therapeutic molecules with first-line anti-TB drugs to treat drug-resistant TB.

Invasive salmonella enteritidis infection complicated by colonic perforations and pancytopenia: A case report.

Salmonellosis caused by bacterial genus Salmonella is associated with a high morbidity and mortality rate. Salmonellae can be divided into typhoidal serotypes (S. enterica ser. Typhi and S. enterica ser. Paratyphi A) and nontyphoidal Salmonella (NTS) serotypes. The two most common NTS serotypes isolated from human sources were S. enterica ser. Typhimurium and S. enterica ser. Enteritidis. NTS infection can present with diverse clinical manifestations, including gastroenteritis, bacteraemia, septic arthritis, osteomyelitis, and endovascular infection. Intestinal perforation is an extremely rare and potentially fatal complication of severe salmonella infection. Herein, we report a case of invasive S. Enteritidis infection complicated by colonic perforation and pancytopenia. Following a colonic resection, the patient received a prolonged course of antimicrobial therapy and eventually recovered.

Tumescent Local Anesthesia in Parotid Abscess - Novel Application of Old Technique.

Tumescent local anesthesia (TLA) is a regional anesthetic technique in which the diluted local anesthetic drug (commonly lidocaine) and epinephrine solution in large volume is injected subcutaneously around the site of incision. The main advantages of TLA are excellent bloodless field and longer duration of analgesia because of addition of epinephrine. Although TLA was used in various surgical procedures, there is no literature to date that has reported its use in the parotid region. Hence, we present an interesting case where this old technique found a novel application in avoiding general anesthesia and its sequelae. We also believe that it provides valuable information to doctors of various categories such as surgeons, Anesthesiologists and general practitioners/family physicians.

Structure and stoichiometry of CTAB-DNA complexes.

We have studied the structure of cetyltrimethylammonium bromide-DNA complexes using small angle x-ray diffraction and elemental analysis. These complexes exhibit a two-dimensional hexagonal phase. The diffraction data have been analyzed using electron density models based on two different structures of these complexes proposed in the literature, which differ in the micelle to DNA stoichiometry. The structure with a 1:2 micelle-DNA stoichiometry is found to be more consistent with the diffraction data. Furthermore, this structure is also supported by the stoichiometry deduced from elemental analysis. Madelung energies of the two structures, calculated from the electrostatic interaction between their cylindrical constituents, give insight into their relative stability.

A link between long non-coding RNA (lncRNA) and thalassaemia: A review.

The long non-coding RNAs (lncRNAs) are the most prevalent and functionally diverse member of the non-coding RNA (ncRNA). The lncRNA has previously been considered to be a form of transcriptional "noise" but recent studies have found that the lncRNA to be associated with various disease conditions. It has also been found to play important roles in various physiological processes such as haemopoiesis, where lncRNA is reported to act as a fine-tuner of this very important process. To date, the effects of dysregulated lncRNA in thalassaemia has not been fully explored. This review article focuses on the possible roles of dysregulated lncRNAs in the pathogenesis of thalassaemia.

Calculation of free and bioavailable vitamin D and its association with bone mineral density in Malaysian women.

INTRODUCTION: Low 25-hydroxyvitamin D [25(OH)D] levels have not been consistently associated with bone mineral density (BMD). It has been suggested that calculation of the free/bioavailable 25(OH)D may correlate better with BMD. We examined this hypothesis in a cohort of Malaysian women. MATERIALS AND METHODS: A cross-sectional study of 77 patients with rheumatoid arthritis (RA) and 29 controls was performed. Serum 25(OH)D was measured using the Roche Cobas E170 immunoassay. Serum vitamin D binding protein (VDBP) was measured using a monoclonal enzyme-linked immunosorbent assay (ELISA). Free/bioavailable 25(OH)D were calculated using both the modified Vermuelen and Bikle formulae. RESULTS: Since there were no significant differences between RA patients and controls for VDBP and 25(OH)D, the dataset was analysed as a whole. Calculated free 25(OH)D by Vermeulen was strongly correlated with Bikle (r = 1.00, p < 0.001). A significant positive correlation was noted between measured total 25(OH)D with free/bioavailable 25(OH)D (r = 0.607, r = 0.637, respectively, p < 0.001). Median free/bioavailable 25(OH)D values were significantly higher in Chinese compared with Malays and Indians, consistent with their median total 25(OH)D. Similar to total 25(OH)D, the free/bioavailable 25(OH)D did not correlate with BMD. CONCLUSION: In this first study of a multiethnic female Malaysian population, free/bioavailable 25(OH)D were found to reflect total 25(OH)D, and was not superior to total 25(OH)D in its correlation with BMD. Should they need to be calculated, the Bikle formula is easier to use but only calculates free 25(OH)D. The Vermuelen formula calculates both free/bioavailable 25(OH)D but is more complex to use.

Nuclear Positioning and Its Translational Dynamics Are Regulated by Cell Geometry.

The collective activity of several molecular motors and other active processes generate large forces for directional motion within the cell, which is vital for a multitude of cellular functions such as migration, division, contraction, transport, and positioning of various organelles. These processes also generate a background of fluctuating forces, which influence intracellular dynamics and thereby create unique biophysical signatures, which are altered in many diseases. In this study, we have used the nucleus as a probe particle to understand the microrheological properties of altered intracellular environments by using micropatterning to confine cells in two structurally and functionally extreme geometries. We find that nuclear positional dynamics is sensitive to the cytoskeletal organization by studying the effect of actin polymerization and nuclear rigidity on the diffusive behavior of the nucleus. Taken together, our results suggest that mapping nuclear positional dynamics provides important insights into biophysical properties of the active cytoplasmic medium. These biophysical signatures have the potential to be used as an ultrasensitive single-cell assay for early disease diagnostics.

Impact of obstructive sleep apnea on neurological recovery after ischemic stroke: A prospective study.

OBJECTIVES: The presence of obstructive sleep apnea (OSA) has been found to adversely affect the neurological recovery after acute ischemic stroke (AIS) in previous observational studies. However, in most of these studies, diagnosis of OSA was based on oximetry data alone, raising concern in the accuracy of diagnosis as well as estimation of severity. Purpose of our study was to determine the prevalence and severity of OSA (based on polysomnography and American Association of Sleep Medicine [AASM] criteria) in patients with AIS and to compare the post-stroke neurological and functional outcome, in those with and without OSA. MATERIALS AND METHODS: A prospective single-centre study was conducted over a period of eighteen months from January 2013. The demographic and clinical data were collected, and the etiology of stroke was classified according to TOAST classification. Subsequently, all selected patients (N=99) underwent premorbid sleep status assessment by Epworth Sleepiness Scale followed by polysomnography using Resmed ApneaLink polysomnograph. Data were analyzed to find out the prevalence and severity of OSA as well as its impact on neurological recovery as assessed by National Institutes of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) at different time points, starting from admission. RESULTS: There was a high prevalence of OSA (~60%) with a quarter of them having severe OSA. The OSA group had a significantly higher mean NIHSS score at discharge (P=.002) and significantly higher mRS score (irrespective of severity of OSA) at all points of evaluation. CONCLUSION: Ischemic stroke patients with OSA tend to have poor neurological and functional recovery, across all segments of stroke and OSA severity.

Tuning DNA-amphiphile condensate architecture with strongly binding counterions.

Electrostatic self-assembly of colloidal and nanoparticles has attracted a lot of attention in recent years, since it offers the possibility of producing novel crystalline structures that have the potential to be used as advanced materials for photonic and other applications. The stoichiometry of these crystals is not constrained by charge neutrality of the two types of particles due to the presence of counterions, and hence a variety of three-dimensional structures have been observed depending on the relative sizes of the particles and their charge. Here we report structural polymorphism of two-dimensional crystals of oppositely charged linear macroions, namely DNA and self-assembled cylindrical micelles of cationic amphiphiles. Our system differs from those studied earlier in terms of the presence of a strongly binding counterion that competes with DNA to bind to the micelle. The presence of these counterions leads to novel structures of these crystals, such as a square lattice and a √3 x √3 superlattice of an underlying hexagonal lattice, determined from a detailed analysis of the small-angle diffraction data. These lower-dimensional equilibrium systems can play an important role in developing a deeper theoretical understanding of the stability of crystals of oppositely charged particles. Further, it should be possible to use the same design principles to fabricate structures on a longer length-scale by an appropriate choice of the two macroions.

Role of bond strength on the lattice thermal expansion and oxide ion conductivity in quaternary pyrochlore solid solutions.

Quaternary pyrochlore-type solid solutions, CaGdZrNb(1-x)Ta(x)O(7) (x = 0, 0.2, 0.4, 0.6, 0.8, 1), were prepared by a high-temperature ceramic route. The pyrochlore phases of the compounds were confirmed by powder X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy. The crystallographic parameters of the pyrochlore compounds were accurately determined by Rietveld analysis of the powder XRD data. The isovalent substitution of Ta in place of Nb at the B site can reveal the effect of chemical bonding on lattice thermal expansion and oxide ion conductivity because both Nb and Ta have the same ionic radius (0.64 Å). Lattice thermal expansion coefficients of the samples were calculated from high-temperature XRD measurements, and it was found that the thermal expansion coefficient decreases with substitution of Ta. Oxide ion conductivity measured by a two-probe method also shows the same trend with substitution of Ta, and this can be attributed to the high bond strength of the Ta-O bond compared to that of the Nb-O bond. Microstructural characterization using scanning electron microscopy proves that the size of the grains has a small effect on the oxide ion conductivity. Our studies established the role of chemical bonding in deciding the conductivity of pyrochlore oxides and confirmed that the 48f-48f mechanism of oxide ion conduction is dominant in pyrochlore oxides.

Influence of micellar size on the structure of surfactant-DNA complexes.

We have studied the structure of complexes of the cationic surfactant dodecyltrimethylammonium bromide (DTAB) with DNA as a function of surfactant to DNA base molar ratio (R) and salt concentration. Small-angle x-ray scattering data show the formation of nematic gels at lower and higher salt concentrations, irrespective of the value of R. Two crystalline phases are observed over intermediate salt concentrations; a square (S) phase for R>3 and a hexagonal (H_{S}) phase for lower R. Electron density maps of these phases show intercalated structures, with DTAB micelles sandwiched between long DNA strands. The composition of these complexes, estimated using elemental analysis, indicates that the micelles are not very long, and they occupy only about half of the interstitial volume between the DNA strands. This phase behavior is strikingly different from that of complexes of DNA with longer chain surfactants cetyltrimethylammonium bromide (CTAB) and tetradecyltrimethylammonium bromide (TTAB), which show only a hexagonal (H) phase over similar ranges of R and salt concentration, the H_{S} structure observed in the present study being a sqrt[3]×sqrt[3] superlattice of the H structure. Madelung energies of the S and H structures, calculated from the electrostatic interaction between their cylindrical constituents, suggest that the former is preferred in DTAB-DNA complexes due to the smaller micellar radius of DTAB. The propensity of DTAB to form short micelles seems also to favor the H_{S} phase at lower R. These results illustrate the important role of micellar size in determining the structure of these two-dimensional macro-ion crystals.

Comparison of performance indicators of MGIT primary culture to assess the impact of implementation of ISO 15189:2012 standards.

Performance indicators are key component and plays a major role for monitoring and continuous quality improvement of the test results. The NABL certificate of accreditation is issued in accordance with the standard ISO 15189:2012 requirements. As part of the accreditation process, the laboratory has acquired knowledge and implemented the quality system procedures. Present study analyzed the impact of the accreditation process on the "performance indicators" of MGIT primary culture and found that performance indicators have been improved significantly after implementation of NABL for almost all indicators which clearly indicate the importance of accreditation and implementation of quality procedures for reliability of valid test results.

Osmotic-pressure-induced phase transition of a surfactant-DNA complex.

We have studied the effect of osmotic pressure on complexes formed by DNA with the cationic surfactant cetyltrimethylammonium tosylate using small-angle x-ray scattering. Earlier studies have shown that these complexes exhibit three different phases depending on the DNA and surfactant concentrations in the solution. The hexagonal superlattice phase (H_{I,s}^{c}) is found to be corralled into the hexagonal phase (H_{I}^{c}) above a threshold osmotic pressure. We have also estimated the DNA to surfactant micelle stoichiometry of the complexes in the three phases using elemental analysis. Our results provide further support for the structures of these complexes proposed earlier based on small-angle x-ray scattering data.

Cerebriform Tongue.

Cerebriform tongue (CT) is diagnosed to be a benign clinical condition that is characterized by grooves on the dorsal surface of the tongue and referred with other terminologies such as the scrotal tongue, grooved tongue, lingua fissurata, and lingua plicata which can be chronic trauma, vitamin deficiencies, and probably not a developmental malformation. The incidence of this condition was predominant among males and found to be higher with increasing age. It is very rarely observed in children. It is usually painless and sometimes food debris accumulation can irritate. CT has been reported with the association of various systemic factors and syndromes. A case of a 62-year-old male with CT is presented along with the review of the literature.

Single-Protein Tracking to Study Protein Interactions During Integrin-Based Migration.

Cell migration is a complex biophysical process which involves the coordination of molecular assemblies including integrin-dependent adhesions, signaling networks and force-generating cytoskeletal structures incorporating both actin polymerization and myosin activity. During the last decades, proteomic studies have generated impressive protein-protein interaction maps, although the subcellular location, duration, strength, sequence, and nature of these interactions are still concealed. In this chapter we describe how recent developments in superresolution microscopy (SRM) and single-protein tracking (SPT) start to unravel protein interactions and actions in subcellular molecular assemblies driving cell migration.

Self-care practices among type II diabetics in rural area of Kancheepuram district, Tamil Nadu.

INTRODUCTION: Type 2 diabetes mellitus is one of the most prevalent noncommunicable diseases in India. The acute and chronic complications of diabetes impact the physical, mental, and social well-being of the patients, thereby, placing a major burden on the health care system. Studies have shown that adequate self-care practices among the patients will facilitate good glycemic control and prevent complications. OBJECTIVES: To study the patterns of self-care practice among diabetic patients and the factors associated with them. METHODS: This descriptive cross-sectional study was carried out among 250 diabetics in the rural field practice area of a Tertiary Medical College and Hospital in Chennai. The participants were interviewed on their diabetic status and various components of self-care practices adopted from The Summary of Diabetes Self-care Activities (SDSCA) Measure. Adherence to medication was assessed by using Morisky Medication Adherence Scale-4 (MMAS-4). RESULTS: Our study observed that the overall prevalence of good self-care practices was very low (5.6%). Moderate self-care practices were prevalent in 42% of the study participants whereas the majority (52.4%) of the study population had poor self-care practices. In our study, the association between self-care activity with educational status and occupation was found to be statistically significant. Adherence was high for blood sugar testing (75.2%) and medication (70.4%) in the study population whereas adherence for foot care was poor (17.6%). CONCLUSION: Our study emphasized on the need for knowledge and awareness to be provided in rural areas regarding diabetes care management and self-care practices. Structured programs need to be planned to improve the attitude and practices of diabetic patients to promote better compliance towards diet, exercise, adherence to drugs, and appropriate foot care.

Workplace based Potentially Malignant Oral Lesions Screening among Tobacco Consuming Migrant Construction Site Workers in Chennai, South India: A Pilot Study.

CONTEXT: Vulnerable population groups such as migrant workers are identified as emerging high-risk groups for oral cancer owing to the high prevalence of smokeless tobacco consumption. Premature deaths due to oral cancer can be prevented by screening the population with high tobacco consumption practices and detecting early reversible stages of oral mucosal cavity lesions and facilitating linkages for further care. AIM: To assess prevalence of potentially malignant oral mucosal cavity lesions among tobacco consuming migrant construction workers in sub-urban Chennai, India. SETTINGS AND DESIGNS: A workplace based cross-sectional study design. MATERIALS AND METHODS: A cross-sectional study was conducted at workplaces i.e., construction sites for screening potentially malignant oral mucosal cavity lesions among migrant workers across 23 construction sites of Chennai during September 2019 - February 2020. An onsite, group health education session was provided about the harms of tobacco use to the migrants. STATISTICAL ANALYSIS USED: Data entered in MS Excel was analysed using SPSS and multivariate analysis was performed. RESULTS: Among 640 migrants included in the study, 411 (64.2%) were less than 30 years of age, 623 (97.4%) were from north-eastern states of India such as West Bengal, Bihar, Rajasthan, Uttar Pradesh, Jharkhand. A considerable size (272, 42.5%) could not read or write and 355 (55.4%) earn a monthly income of less than ten thousand rupees. Current tobacco users were 619 (96.7%), smokeless tobacco users (463, 72.34%), smokers (206, 32.2%) and dual users (52,8.12%). Inflammatory mucosal lesions in the oral cavity were 70.97% and more among smokeless tobacco users comparable to 22.58% among tobacco smokers and was significantly associated with up to 20 years of tobacco consumption. CONCLUSIONS: Prevalence of Potentially malignant oral lesions among smokeless tobacco using interstate migrant construction site workers is very high and need urgent interventions.

A profile of bacteriologically confirmed pulmonary tuberculosis in children.

OBJECTIVE: To describe the clinical profile of children with bacteriologically confirmed tuberculosis. STUDY DESIGN: A multicentric study was conducted in three hospitals in Chennai city between July 1995 and December 1997. Children aged 6 months to 12 years with signs and symptoms suggestive of tuberculosis were investigated further. Clinical examination, chest radiograph, tuberculin skin test with 1 TU PPD and, sputum or gastric lavage for mycobacterial smear and culture were done for all and, lymph node biopsy when necessary. RESULTS: A total of 2652 children were registered and tuberculosis was bacteriologically confirmed in 201. Predominant symptoms were history of an insidious illness (49%), fever and cough (47%), loss of weight (41%) and a visible glandular swelling (49%). Respiratory signs were few and 62% were undernourished. Over half the patients with confirmed TB had normal chest X-ray. Abnormal X-ray findings included parenchymal opacities in 47% and hilar or mediastinal lymphadenopathy in 26%. The prevalence of isoniazid resistance was 12.6% and MDR TB 4%. CONCLUSIONS: Children with tuberculosis present with fever and cough of insidious onset. Lymphadenopathy is a common feature even in children with pulmonary TB. A significant proportion of children have normal chest X-rays despite positive gastric aspirate cultures. Drug resistance rates in children mirror the pattern seen in adults in this geographic area.

Rheological characterisation of concentrated domestic slurry.

The much over-looked element in new sanitation, the transport systems which bridge the source and treatment facilities, is the focus of this study. The knowledge of rheological properties of concentrated domestic slurry is essential for the design of the waste collection and transport systems. To investigate these properties, samples were collected from a pilot sanitation system in the Netherlands. Two types of slurries were examined: black water (consisting of human faecal waste, urine, and flushed water from vacuum toilets) and black water with ground kitchen waste. Rheograms of these slurries were obtained using a narrow gap rotating rheometer and modelled using a Herschel-Bulkley model. The effect of concentration on the slurry are described through the changes in the parameters of the Herschel-Bulkley model. A detailed method is proposed on estimating the parameters for the rheological models. For the black water, yield stress and consistency index follow an increasing power law with the concentration and the behaviour index follows a decreasing power law. The influence of temperature on the viscosity of the slurry is described using an Arrhenius type relation. The viscosity of black water decreases with temperature. As for the black water mixed with ground kitchen waste, it is found that the viscosity increases with concentration and decreases with temperature. The viscosity of black-water with ground kitchen waste is found to be higher than that of black water, which can be attributed to the presence of larger particles in the slurry.