Efficient elimination of airborne pathogens: a study on aerosolized Mycobacterium tuberculosis and SARS-CoV-2 using ZeBox technology.

BACKGROUND: Despite multifactorial evidence, the safe and effective elimination of free-floating micro-organisms remains a significant scientific challenge. ZeBox Technology exploits microbial Zeta Potential, to extract and eliminate them from free-flowing air, using a non-ionizing electric field, in combination with a microbicidal surface. AIM: Evaluation of ZeBox Technology against aerosolized SARS-CoV-2 and Mycobacterium tuberculosis under controlled conditions. METHODS: SARS-CoV-2 and M. tuberculosis H37Ra were used in this study. Individual micro-organisms were aerosolized using a Collison nebulizer inside an air-sealed test chamber. Air samples were collected from the chamber on to a Mixed Cellulose Ester membrane, at various time points, and used for enumeration. SARS-CoV-2 was enumerated using qRT-PCR, while M. tuberculosis H37Ra was quantified using standard microbiological procedures. FINDINGS: We established a viable aerosolized microbial load of ∼10E9 and ∼10E6 for SARS-CoV-2 and M. tuberculosis H37Ra, respectively, inside the test chamber. Under ideal conditions, the floating microbial load was at a steady-state level of 10E9 for SARS-CoV-2 and 10E6 for M. tuberculosis. When the ZeBox-Technology-enabled device was operated, the microbial load reduced significantly. A reduction of ∼10E4.7 was observed for M. tuberculosis, while a reduction of ∼10E7 for SARS-CoV-2 was observed within a short duration. The reduction in airborne SARS-CoV-2 load was qualitatively and quantitatively measured using fluorescence analysis and qRT-PCR methods, respectively. CONCLUSION: This validation demonstrates the efficacy of the developed technology against two of the deadliest micro-organisms that claim millions of lives worldwide. In conjunction with the existing reports, the present validation proved the true broad-spectrum elimination capability of ZeBox technology.

Effectiveness of a novel, non-intrusive, continuous-use air decontamination technology to reduce microbial contamination in clinical settings: a multi-centric study.

BACKGROUND: Despite rigorous disinfection and fumigation, healthcare-associated infection (HAI) remains a significant concern in healthcare settings. We have developed a novel airborne-microbicidal technology 'ZeBox' which clears >99.999% of airborne microbial load under controlled laboratory conditions. AIM: To evaluate the clinical performance of ZeBox in reducing airborne and surface microbial load. METHODS: The study was conducted in single-bed and multi-bed intensive care units (ICUs) of two hospitals. Airborne and surface microbial loads were sampled pre and post deployment of ZeBox at pre-determined sites. Statistical significance of the reduction was determined using the Mann-Whitney U-test. FINDINGS: ZeBox brought statistically significant reduction of both airborne and surface bacterial and fungal load. In both hospital ICUs, airborne and surface bacterial load decreased by 90% and 75% on average respectively, providing a low bioburden zone of 10-15 feet diameter around the unit. The reduced microbial level was maintained during ZeBox's operation over several weeks. Most clinical bacterial isolates recovered from one of the hospitals were antibiotic resistant, highlighting ZeBox's ability to eliminate antimicrobial-resistant bacteria among others. CONCLUSION: ZeBox significantly reduces airborne and surface microbial burden in clinical settings. It thereby serves an unmet need for reducing the incidence of HAI.

A comparative study of heart rate variability tests and lipid profile in healthy young adult males and females.

BACKGROUND: Coronary Heart Disease (CHD) is the leading cause of death in many developed countries. The relation between heart rate variability (HRV) and CHD was recently explored after the development of HRV techniques. Lower HRV was proven to be associated with a greater risk for developing hypertension among normotensive men, and hypertension is one of the major risk factors of CHD. Acute myocardial infarction is accompanied by decreased HRV, which is due to reduced vagal or increased sympathetic outflow to the heart. AIM: This study was designed to test the hypothesis of influence of gender and lipid profile difference on heart rate variability tests. MATERIALS AND METHODS: Thirty healthy adult male and thirty healthy adult female subjects in the age group of 18- 25 years without any addictions and gross systemic disease were selected. Heart rate variability tests during Valsalva maneuver, deep breathing and 30:15 R-R intervals ratio were carried and lipid profile of the subjects were analyzed. RESULTS: We found a decrease in values of HRV tests during the Valsalva maneuver, deep breathing in male individuals as compared with age- and Body Mass Index, BMI-matched females. VHeart Rate Variability tests during 30:15 R-R intervals Ratio in male individuals were significantly decreased as compared with females. Values of total cholesterol, Low Density Lipoprotein, LDL cholesterol were found to be significantly increased and High Density Lipoprotein, HDL cholesterol significantly decreased in males. CONCLUSION: Healthy adult males may be at a higher risk of developing acute myocardial infarction and CHD due to decreased HRV and atherogenic lipid profile. Lower level of serum estrogen may be the cause of this difference in HRV among males. The difference in HRV tests among males and females disappears after menopause.

Relation of microalbuminuria to glycosylated hemoglobin and duration of type 2 diabetes.

BACKGROUND: Nephropathy is one of the complications of type 2 diabetes mellitus that could lead to end-stage renal disease. Persistent microalbuminuria is the best predictor of high risk of developing diabetic nephropathy. The relation between HbA 1c and microalbuminuria with the duration of diabetes is not clear. OBJECTIVES: To determine microalbuminuria levels in type 2 diabetics and to correlate changes in microalbuminuria levels to glycosylated hemoglobin level and duration of diabetes. MATERIALS AND METHODS: Study was conducted at Medical College, Kolkata. Fifty both male and female type 2 diabetics of age groups 30-60 years, without any complications were taken as cases and 50 healthy (male and female) subjects of comparable age were taken as controls. Cases with anemia, any other diseases or person using drugs that could affect HbA 1c levels and microalbuminuria were excluded from the study. Fasting and postprandial blood glucose, HbA 1c serum urea and serum creatinine were analyzed. Urine was analyzed for microalbuminuria. The Statistical Software SPSS 15.0 were used for the analysis of the data. RESULTS: Urinary microalbumin, HbA 1c levels were significantly higher in the cases. Microalbumin levels were linearly correlated to the duration of diabetes and HbA 1c. CONCLUSIONS: Impaired glycemic control is associated with significant elevations in urinary microalbumin levels. Furthermore, there is an increased urinary microalbumin levels with increased duration of diabetes, which suggests that the detection of increased urinary microalbumin levels at the initial stage can avert, reduce the clinical and economic burden of diabetic complications in future.

Relation of iron stores to oxidative stress in type 2 diabetes.

BACKGROUND: Recent studies revealed elevated serum ferritin levels predict new-onset type 2 diabetes. Further studies proved ferritin to be an important and independent predictor of the development of diabetes. The link between hyperglycemia, enhanced free radical activity (oxidative stress) and serum iron and its stores (serum ferritin levels) levels is not clear. OBJECTIVES: The present study is an attempt to understand the relationship between serum ferritin levels and oxidative stress (measured by malondialdehyde). MATERIALS AND METHODS: The study comprised of 30 apparently healthy controls and 30 type 2 diabetic patients who attended the outpatient and inpatient departments of Medical College, Kolkata. Levels of fasting blood glucose, postprandial blood glucose, serum iron, serum ferritin, glycosylated hemoglobin (HbA1c) and malondialdehyde (MDA), serum urea and creatinine were estimated. The statistical software SPSS 11.0 and Systat 8.0 were used for the analysis of the data and Microsoft Word and Excel have been used to generate tables and graphs. RESULTS: Serum iron (82.16 ± 13.24 µg/dl), serum ferritin (224.53 ± 96.06 µg/L), HbA1c (8.62 ± 1.79%), MDA (2.66 ± 0.76 nmol/ml) levels were significantly higher in type 2 diabetics compared with apparently healthy controls. Elevations in serum iron, ferritin and HbA1c are accompanied by a parallel increase in blood glucose. Based on groups of glycemic control, i.e. HbA1c levels >8%, serum ferritin levels were highest, 258.63 ± 22.67 µg/dl. There is an inverse correlation of serum ferritin levels to MDA levels in the diabetic cases of longer duration of more than 10 years. CONCLUSION: Serum ferritin level in the present study is found to be higher in the newly diagnosed cases and lower in those patients suffering from diabetes for more than 10 years. This study probably suggests that serum ferritin can represent either as a pro-oxidant or as an antioxidant in a time-dependent manner.

Prevalence of Tinea capitis in school going children in Kolkata, West Bengal.

BACKGROUND: In recent years the incidence of Tinea capitis, infection of scalp by dermatophytes, has increased in United Kingdom and North America. The trend may be similar in India. The objective of this study is to find the prevalence of Tinea capitis in school going urban children in Kolkata, West Bengal state. MATERIALS AND METHODS: The present study is a cross-sectional study conducted in a government higher primary school in Kolkata. RESULTS: Totally 505 students were screened and 52 were diagnosed to have Tinea capitis by clinical examination, giving a prevalence rate of 10% among school children. Prevalence rates among the age groups of 6-8, 9-11 and 12-14 years were almost the same, ranging from 9 to 11%. The prevalence rate was significantly high among the boys (14%). There was no significant difference in prevalence of infection among coconut oil users and castor oil users. Measures of general hygiene were similar among those who were infected with Tinea capitis and those who were not. The commonest clinical type of infection found was dull grey patches. Itching with hair loss was the major symptom and most of the infected children had cervical lymphadenopathy. The potassium hydroxide studies revealed endothrix spores in majority of samples. CONCLUSION: Tinea capitis in prevalent in school going urban children in Kolkata, West Bengal state and necessary measures must be undertaken to curtail this incidence.

Comparison of bioactive glass coated and hydroxyapatite coated titanium dental implants in the human jaw bone.

BACKGROUND: Current trends in clinical dental implant therapy include modification of titanium surfaces for the purpose of improving osseointegration by different additive (bioactive coatings) and subtractive processes (acid etching, grit-blasting). The aim of this study was to evaluate and compare the behaviour of hydroxyapatite and the newly developed bioactive glass coated implants (62 implants) in osseous tissue following implantation in 31 patients. METHODS: Bioactive glass and hydroxyapatite was suitably coated on titanium alloy. Hydroxyapatite coating was applied on the implant surface by air microplasma spray technique and bioactive glass coating was applied by vitreous enamelling technique. The outcome was assessed up to 12 months after prosthetic loading using different clinical and radiological parameters. RESULTS: Hydroxyapatite and bioactive glass coating materials were non-toxic and biocompatible. Overall results showed that bioactive glass coated implants were as equally successful as hydroxyapatite in achieving osseointegration and supporting final restorations. CONCLUSIONS: The newly developed bioactive glass is a good alternative coating material for dental implants.

Application of chemically modified rice husk for the removal of heavy metals from aqueous solution.

The removal efficiency of lead, cadmium and zinc from aqueous solution on adsorption by using rice husk, a non-conventional material in its natural and chemically modified form has been presented in this paper. It has been observed that rate of adsorption is dependent on the nature of the adsorbent, adsorbent dose, particle size of the adsorbent, concentration, pH, contact time, temperature, etc. Under identical experimental condition chemically modified rice husk was found to possess greater adsorption capacity for all metals than untreated rice husk and chemically modified rice husk ash. Chemically modified rice husk could remove 99.8% Pb, 95% Cd and 97% Zn from aqueous solution at room temperature.

Leaching of lead and cadmium from glass dinnerware.

Heavy metals like lead and cadmium were found to leach out from food contact surface of opal glass dinnerware when treated with five food acids as a leaching solution. The leachates used were: acetic acid, tartaric acid, citric acid, lactic acid and ascorbic acid at three different concentrations 2%, 4%, and 8% (v/v). At room temperature, duration of leaching varied from 1h to 24h in each case. The amount of metals leached in individual acid was found to be maximum at the 4% acid concentration. Release of Pb and Cd was faster in first 2h leaching period. Maximum amount of Pb and Cd were leached in 4% acetic acid at room temperature.

Spectrophotometric determination of platinum in glass after extraction with polyurethane foam.

A spectrophotometric method has been developed for determination of trace amounts of platinum in glass. The method is based on the extraction of platinum(II) from 1M hydrochloric acid containing 0.2M stannous chloride and 4 x 10(-4)M dithizone onto polyurethane foam, elution with acetone (containing 3% v/v concentrated hydrochloric acid) and measurement of the absorbance of the eluate at 530 nm. Beer's law is obeyed up to 10.0 microg/ml Pt. The minimum platinum level in the eluate that can be determined by this method is 0.1 microg/ml.

CpG methylation of viral DNA in EBV-associated tumours.

In EBV-immortalized lymphoblastoid cell lines (LCLs) a small number of "latent" proteins are expressed. These are the EBV nuclear antigens, EBNAs 1-6, and a latent membrane protein, LMP. We have investigated the expression of these proteins in a variety of EBV-associated tumours and cell lines. Whereas transplant and B-cell lymphomas from cotton-top tamarins appear to express the full range of antigens found in LCLs, we and others have found that in Burkitt's lymphomas (BL) and a nasopharyngeal carcinoma (NPC) isolate, EBNA expression is restricted to EBNA-I. (In NPC, but not in BL, LMP may also be expressed). In order to ask what restricts the expression of EBNA 2-6 in NPC and BL cells it seemed reasonable to consider the possibility that the DNA sequences normally regulating expression of these antigens could be chemically modified. In this analysis, a tight inverse correlation between methylation of CpG dinucleotides in the 5' flanking region of the EBNA-2 gene and the expression of EBNAs 2-6 has been revealed. In the NPC tumour, CpG methylation within the gene is also observed, as is specific methylation over the EBNA-I region I and II binding sites (in oriP). The significance of these observations is considered.

Growth of adult human cells in culture at clonal densities.

The effect of varying medium concentrations of fetal calf serum (FCS), horse serum (HS) and chicken embryo extract (EE) on the growth capacity of adult human cells cultured at clonal densities was investigated. The best growth was consistently obtained with medium containing 20 parts FCS and 2 parts heat-treated commercial EE. The growth potential of human muscle cells was not related to the age of the patient from which the biopsy was taken, but was dependent on the microenvironment of the culture and the cell density.

Acquired resistance to daunorubicin in a patient with acute myelogenous leukaemia.

Measurement of in vitro and in vivo resistance to daunorubicin in AML patients suggests that there is no simple correlation between the two. In a patient who became clinically resistant and whose cells showed a parallel increased resistance in vitro we found the acquisition of multiple drug resistance. The increased in vitro resistance to daunorubicin could to some extent be overcome by conjugating daunorubicin to DNA.