Is a differentiated care model needed for patients with TB? A cohort analysis of risk factors contributing to unfavourable outcomes among TB patients in two states in South India.

BACKGROUND: TB is a preventable and treatable disease. Yet, successful treatment outcomes at desired levels are elusive in many national TB programs, including India. We aim to identify risk factors for unfavourable outcomes to TB treatment, in order to subsequently design a care model that would improve treatment outcomes among these at-risk patients. METHODS: We conducted a cohort analysis among TB patients who had been recently initiated on treatment. The study was part of the internal program evaluation of a USAID-THALI project, implemented in select towns/cities of Karnataka and Telangana, south India. Community Health Workers (CHWs) under the project, used a pre-designed tool to assess TB patients for potential risks of an unfavourable outcome. CHWs followed up this cohort of patients until treatment outcomes were declared. We extracted treatment outcomes from patient's follow-up data and from the Nikshay portal. The specific cohort of patients included in our study were those whose risk was assessed during July and September, 2018, subsequent to conceptualisation, tool finalisation and CHW training. We used bivariate and multivariate logistic regression to assess each of the individual and combined risks against unfavourable outcomes; death alone, or death, lost to follow up and treatment failure, combined as 'unfavourable outcome'. RESULTS: A significantly higher likelihood of death and experiencing unfavourable outcome was observed for individuals having more than one risk (AOR: 4.19; 95% CI: 2.47-7.11 for death; AOR 2.21; 95% CI: 1.56-3.12 for unfavourable outcome) or only one risk (AOR: 3.28; 95% CI: 2.11-5.10 for death; AOR 1.71; 95% CI: 1.29-2.26 for unfavourable outcome) as compared to TB patients with no identified risk. Male, a lower education status, an initial weight below the national median weight, co-existing HIV, previous history of treatment, drug-resistant TB, and regular alcohol use had significantly higher odds of death and unfavourable outcome, while age > 60 was only associated with higher odds of death. CONCLUSION: A rapid risk assessment at treatment initiation can identify factors that are associated with unfavourable outcomes. TB programs could intensify care and support to these patients, in order to optimise treatment outcomes among TB patients.

Chitosan-mediated crystallization and assembly of hydroxyapatite nanoparticles into hybrid nanostructured films.

The synthesis and subsequent assembly of nearly spherical nano-hydroxyapatite (nHA) particles in the presence of trace amounts of the polysaccharide chitosan was carried out employing a wet chemical approach. Chitosan addition during synthesis not only modulated HA crystallization but also aided in the assembly of nHA particles onto itself. Solvent extraction from these suspensions formed iridescent films, of which the bottom few layers were rich in self-assembled nHA particle arrays. The cross-section of these hybrid films revealed compositional and hence structural grading of the two phases and exhibited a unique morphology in which assembled nHA particles gradually gave way to chitosan-rich top layers. Transmission electron microscope and selected area electron diffraction studies suggested that the basal plane of HA had interacted with chitosan, and scanning electron microscope studies of the hybrid films revealed multi-length scale hierarchical architecture composed of HA and chitosan. Phase identification was carried out by X-ray diffraction (XRD) and Rietveld analysis of digitized XRD data showed that the basic apatite structure was preserved, but chitosan inclusion induced subtle changes to the HA unit cell. The refinement of crystallite shape using the Popa method clearly indicated a distinct change in the growth direction of HA crystallites from [001] to [100] with increasing chitosan concentration. The paper also discusses the likelihood of chitosan phosphorylation during synthesis, which we believe to be a pathway, by which chitosan molecules chemically interact with calcium phosphate precursor compounds and orchestrate the crystallization of nHA particles. Additionally, the paper suggests several interesting biomedical applications for graded nHA-chitosan nanostructured films.

Conductometric study of precursor compound formation during wet-chemical synthesis of nanocrystalline hydroxyapatite.

Conductometry was employed to study the phase evolution of calcium phosphate compounds during the wet-chemical synthesis of hydroxyapatite (HA). Calcium hydroxide and orthophosphoric acid were used to prepare HA at various temperatures ranging from 30 to 95 degrees C. The electrical conductivity and pH of the reaction mixture were measured at regular intervals of time during acid addition, and the rate of change of conductivity was used to decipher the end point of the reaction. Our previous studies have shown that the end product of this reaction route yields mildly carbonated crystalline HA. The trend of the change in conductivity with time was similar at all temperatures. The conductivity curves were divided into three regions based on the variation in slope of the curves. The slope of the curves decreased with increasing temperatures in the first two regions, and the slope is greater in the second region than in the first. From the conductivity and pH measurement results, the possible precursor phase was identified and it had the composition Ca(3)(PO(4))(2). The kinetics of phase transformation was also analyzed and compared to previous work. The similarities between this work and the traditionally adapted experimental work for phase formation and transformation kinetics are highlighted, and the novelty in the current work is discussed.

Profile of ocular trauma in industries-related hospital.

INTRODUCTION: Ocular trauma is a worldwide cause of visual morbidity, a significant proportion of which occurs in the industrial workplace and includes a spectrum of simple ocular surface foreign bodies, abrasions to devastating perforating injuries causing blindness. Being preventable is of social and medical concern. AIM: A prospective case series study, to know the profile of ocular trauma at a hospital caters exclusively to factory employees and their families, to co-relate their demographic and clinical profile and to identify the risk factors. MATERIALS AND METHODS: Patients with ocular trauma who presented at ESIC Model hospital, Rajajinagar, Bangalore, from June 2010 to May 2011 were taken a detailed demographic data, nature and cause of injury, time interval between the time of injury and presentation along with any treatment received. Ocular evaluation including visual acuity, anterior and posterior segment findings, intra-ocular pressure and gonio-scopy in closed globe injuries, X-rays for intraocular foreign body, B-scan and CT scan were done. Data analyzed as per the ocular trauma classification group. The rehabilitation undertaken medically or surgically was analyzed. At follow-up, the final best corrected visual acuity was noted. RESULTS: A total of 306 cases of ocular trauma were reported; predominantly in 20-40 year age group (72.2%) and in men (75%). The work place related cases were 50.7%and of these, fall of foreign bodies led the list. Visual prognosis was poorer in road traffic accidents rather than work place injuries owing to higher occurrence of open globe injuries and optic neuropathy. Finally, 11% of injured cases ended up with poor vision. CONCLUSION: Targeting groups most at risk, providing effective eye protection, and developing workplace safety cultures may together reduce occupational eye injuries.

Apparent solubility of hydroxyapatite in aqueous medium and its influence on the morphology of nanocrystallites with precipitation temperature.

Two differing wet-chemical synthesis routes, Ca(OH)2 + H3PO4 and CaCl2 + Na3PO4/NaOH, were used to prepare hydroxyapatite (HA) at various temperatures ranging from 30 to 95 degrees C. The electrical conductivity of the solution was measured at regular intervals of time during H3PO4 and Na3PO4 addition to the suspension/solution containing Ca2+ ions. The rate of change of conductivity is used to note the end point of the reaction. X-ray diffraction of the dried, precipitated particles revealed HA as the predominant phase, and the FTIR spectroscopy studies indicated the presence of CO3(2-) groups which substituted PO4(3-) groups in the HA lattice (B-type). FESEM observations revealed that the aspect ratio of the particles decreased with increasing precipitation reaction temperature in one system [Ca(OH)2 + H3PO4] and in the other system it increased with increasing temperature. The changes in the morphology with temperature were analyzed through conductivity measurements and the thermochemical properties of the reaction systems. Conductivity measurements showed that the concentration of dissolved ions at the end point of the reaction between Ca(OH)2 and H3PO4 increased, indicating an increased apparent solubility of HA with increasing temperature, whereas the end-point conductivity did not increase noticeably in the other reaction system.

On the kinetics of apatite growth on substrates under physiological conditions.

Derived from reaction kinetics, a simple but useful method, based on "apatite forming capacity" or AFC of solutions mimicking blood plasma, is proposed to decipher the rate of calcium phosphate mineralization. Apatite growth rate constants were calculated using this method for a model composite surface varying the volume fraction of synthetic hydroxyapatite (HA) in a polymer matrix. Previously reported data for mineralized surfaces on Ta, Ti, and its alloys are also analyzed similarly and compared. Utilizing the growth rate constant, the bioactivity of the materials was indexed in vitro. Complementarily, semiempirical quantum mechanical calculation (ZINDO method) showed that the interaction of cations with TRIS-hydroxymethyl aminomethane molecules in the solution is stronger than that with the polymer substrate considered, but weaker than hydrated Ti and TiO(2) surfaces. This analysis then quantifies for example the extent of polymer inertness and the "bioactivity" of alkali treated Ti. The growth rate constants for the model materials prepared in this work are explained on the basis of localized dissolution of HA, the amount of which simply increases with increasing volume fraction of HA in the composite.

Temperature driven morphological changes of chemically precipitated hydroxyapatite nanoparticles.

Hydroxyapatite (HA) is synthesized by a wet chemical route using calcium hydroxide and ortho-phosphoric acid at various temperatures (40, 80, and 100 degrees C). X-ray diffraction of the precipitate particles revealed HA as the predominant phase (>99%) with a small amount of beta-tricalcium phosphate. Fourier transform infrared spectroscopy indicated the presence of carbonate substitution, which decreased with increasing temperature. Transmission electron microscopy observations revealed needle-shaped particles with a high aspect ratio at 40 degrees C, which changed to spheroidal when the precipitation temperature was increased to 100 degrees C. The changes in the morphology with temperature were analyzed taking into account the driving force for the HA precipitation and the supersaturation level of Ca2+ and PO4(3-) ions with respect to HA. The analysis indicated that the supersaturation level of the reactants, especially the concentration of Ca2+ ions, played a predominant role on the precipitate morphology for this classical acid-base reaction.