Determinants of Vitamin D Deficiency Among Under-five Children in Urban Slums of Mumbai, India

A community-based study was undertaken in an urban slum in Mumbai, between October, 2015 and September, 2017 among 426 healthy children (aged 1-5 years) to assess prevalence of vitamin D deficiency (VDD) and its determinants. VDD was classified as 25(OH)D <20 ng/mL. The prevalence of VDD was 76.8% (n=327), and sun-exposure, male sex, and calcium and vitamin D supplementations during infancy were important determinants. Routine supplementation with vitamin D in infancy is likely to reduce the occurrence of VDD in children.

Age-related changes in sex steroid levels influence bone mineral density in healthy Indian men

SUMMARY

Age-related changes in sex steroid levels and its contribution to variations in rate of bone loss among men is unclear. Although, Bio-T and Bio-E(2) levels declined with age and depicted an association with BMD in healthy Indian men, Bio-E(2) was found to be an independent predictor of BMD.

INTRODUCTION

Ethnicity influences sex steroid levels, therefore, their role in pathogenesis of low bone mass needs to be established in various populations. We assessed the extent of changes in sex steroid levels with age and related these to bone mineral density (BMD) in healthy Indian men.

METHODS

Total testosterone (TT), estradiol (E(2)), sex hormone-binding globulin (SHBG), PTH, osteocalcin (OC), and c-terminal telopeptide (CTX) were measured in 330 men aged 20-55 years and correlated with BMD measured by DXA.

RESULTS

Both Bio-T (1% per year) and Bio-E(2) (0.8% per year) levels decreased significantly in ageing men, whereas TT (0.4% per year) and E(2) (0.3% per year) levels decreased only marginally with age. In contrast, SHBG (1.4% per year) and PTH (1% per year) levels increased significantly with age. Serum TT (r = 0.19, p = 0.01) and Bio-T (r = 0.2, p = 0.01) levels were associated positively with BMD at spine, whereas E(2) and Bio-E(2) levels were associated with BMD at spine [E (2) (r = 0.31, p < 0.0001); Bio-E(2) r = 0.37, p < 0.0001] and femur (E(2) r = 0.26, p = 0.001; Bio-E(2) r = 0.27, p = 0.001). Men in the lowest quartile of Bio-E(2) were associated with lower BMD and higher bone turnover.

CONCLUSIONS

Age-related decrease in bioavailable sex steroid levels is associated with BMD in healthy Indian men. Bio-E(2) was found to be an independent predictor of BMD.

Hormonal profiles and biochemical indices of bone turnover in Indian women

The study establishes Indian referent database for bone turnover markers. The levels of markers decreased across the four quartiles of BMD showing a negative correlation with BMD. The study depicts that levels of hormones and bone turnover makers can aid in identifying women at risk for osteoporosis.

INTRODUCTION

Biochemical markers of bone turnover reflect changes in bone metabolism earlier and aid in the management of osteoporosis. Since a referent database for Indian women is lacking, the study was initiated to establish the same and suggest that hormonal profiles and markers of bone turnover can aid in identifying women at risk for osteoporosis.

METHODS

Osteocalcin (OC), bone specific alkaline phosphatase ((BSAP), C-terminal crosslinking telopeptide of type-I collagen (CTX-I), deoxypyridinoline (DPD), follicle-stimulating hormone (FSH) and estrone glucuronide (E(1)G) were measured in 365 Indian women (20-70 years) and correlated with BMD measurements by dual energy absorptiometry (DXA) using one way analysis of variance (ANOVA).

RESULTS

The mean levels of bone resorption markers; CTX-I and DPD increased significantly across the age showing a negative correlation with BMD. The increase in levels of CTX-I and DPD was significantly higher (p < 0.0001) as compared to the femoral and spinal BMD, which dropped only 30-36%. The levels of bone turnover markers and FSH decreased across the four quartiles of spinal and femoral BMD showing a negative correlation whereas E(1)G levels increased across the four quartiles.

CONCLUSION

The bone turnover markers were comparatively low in cohort of Indian women studied.

22q11 microdeletion studies in the heart tissue of an abortus involving a familial form of congenital heart disease

Microdeletion of chromosome 22 is responsible for DiGeorge syndrome, Velo Cardio Facial syndrome, and conotruncal defects. Here, we report on a case of microdeletion 22q11.2 in the heart tissue of a miscarried fetus in a family whose two children had died due to complex congenital heart disease. Fluorescence in situ hybridization (FISH) analysis in the couple revealed that the mother was mosaic for microdeletion of chromosome 22q11.2 in 10% of her peripheral lymphocytes. Prenatal diagnosis was offered to her in her third pregnancy. On routine ultrasonography at 10 weeks, the overall view of the heart was normal. However, before any further tests could be performed, she miscarried at 16 weeks. FISH studies on the heart tissue of the abortus revealed 22q11.2 microdeletion with two different cell lines. This suggests the importance of performing FISH studies when there is a history of congenital heart disease, even though ultrasonography shows a normal view of the heart.

Feasibility of determination of fertile period in Indian women based on urinary hormone estimations

Baseline data available on the excretory profiles of estrone giucuronide (E(1)G), pregnanediol glucuronide (PdG) and luteinising hormone (LH) on human menstrual cycles (n=104) was retrospectively analysed for identifying the limits of fertile period (FP) to be used as natural method of family planning. The limits of fertile period are suggested based on centile distribution of E(1)G and PdG levels during defined phase of menstrual cycle. Two approaches, which do not involve any mathematical calculation are suggested. In approach A, fertile period is said to have started when E(1)G value of 35 ng/ml is reached and is said to have ended when the PdG value of 2 μg/ml on two consecutive days is obtained. The criteria were applied to 30 test cycles in whom authentic fertile period was identified based on excretory profiles of E(1)G, PdG and LH throughout the menstrual cycles. When approach A was followed the authentic fertile period was covered in 27 cycles giving an accuracy of 90% with a mean fertile period length of 9.11+1.9 days. In approach B, the cut off limit of E(1)G value was increased to 55 ng/ml in order to reduce the days of abstinence. Though the length of the fertile period was reduced to 7.2+1.5 days the accuracy of the approach was 66.6%. Thus the approach A which has accuracy of 90% may appeal to determined couples who wish to practice family planning by periodic abstinence or restrict the use of barrier methods.

A comparison of performances of four enzymes used in ELISA with special reference to beta-lactamase

Horse radish peroxidase, alkaline phaosphatase and beta-D-galactosidase are widely used as labels in the development of enzyme immunoassays (EIAs). Enzyme beta-lactamase, though introduced as a label in late seventies has not yet become very popular inspite of having the necessary features of an enzyme to be used in EIAs. The present article reviews assays developed with this enzyme, highlights its salient features and brings out an argument in favour of its wide spread use in EIAs.

A multicentric evaluation study of an indigenously prepared cost effective prototype pregnancy test

A multicentric evaluation of an indigenously developed pregnancy detection kit (named Preglisa) based on urinary human chorionic gonadotropin (hCG) detection was carried out at 12 centres where the outcome of the kit was compared with the existing parameter (e.g., ultrasonography, clinical judgement, serum beta hCG levels) used by the centre for confirmation of the pregnancy. The specificity, sensitivity and accuracy of the kit were 98.05, 98.7 and 98.69 per cent (n = 382) when results of Preglisa were compared with those of non-immunological tests. When compared with commercially available kits, sensitivity was 97.9 per cent, specificity was 97.2 per cent and accuracy was 97.94 per cent (n = 155). The kit is cost effective with a sensitivity of 300 mlU/ml and is recommended for detecting pregnancy 35 days after the last menstrual period thus fulfilling the general requirement in the Indian situation.

Stability studies of the components of a prototype penicillinase (beta-lactamase)-linked ELISA kit

Penicillinase (beta-lactamase) enzyme-linked immunosorbent assay (ELISA) for various reproductive hormones developed in the laboratory were found to have wide applicability in the fertility check clinic of the Institute. A need was thought to transform these assays into ready-to-use kit forms. Therefore, prototype ELISA kits for these hormones were developed and stability of the individual component was ascertained at various temperatures (room temperature, 37 degrees C and 2-8 degrees C). Stability studies were conducted on previously validated assay for pregnanediol-3 alpha-glucuronide (PdG). The studies showed that immunosorbents (antibody coated plates) are stable at room temperature for a period of 2 weeks, at 37 degrees C for 1 week and at 2-8 degrees C for a period of 9 months when preserved after treatment with glycerol solution. The lyophilised conjugate, standard and immunoassay buffer, colour reagent, and its substrate were stable at 37 degrees C up to 1 week and at room temperature up to 2 weeks and at 2-8 degrees C for a period of 6 months, during which the stability was studied.

An indirect ELISA for urinary gonadotropins using immobilized human menopausal gonadotropin

An indirect ELISA for the estimation of urinary gonadotropins is described. Human menopausal gonadotropin is adsorbed on a microtitre plate, where it serves as an immunosorbent. The residual antigonadotropin antibody is captured by the immunosorbent after reaction with the sample or standard and detected with enzyme-labelled antispecies antibody (antirabbit gamma-globulin-horse radish peroxidase). The assay developed here is rapid and satisfies usual validatory criteria expected from an immunoassay. Moreover, it obviates the need for extraction of samples with acetone, as shown by the close agreement between the respective lutropin or follitropin concentrations in extracted and unextracted urine samples.

Importance of selection of separation system in the development of enzyme immunoassay: an experience with follicle stimulating hormone (FSH) assay

An antiserum to follicle stimulating hormone (FSH) obtained as a gift from National Institute of Health (NIH), U.S.A. could not be adsorbed on microtitre ELISA plates, although two other FSH antisera raised in authors' laboratory could be adsorbed. A good precision profile for the FSH assay using these three antisera could be achieved with only one separation system viz. solid phase anti rabbit gamma globulin (ARGG), out of the five separation systems tried. The study suggests that a few antisera used for radio-immunoassay (RIA) purposes may not by themselves get adsorbed on plastic plates. However, they could be effectively used for ELISA purposes using solid phase second antibody.

A simple ELISA for detection of ovulation

A rapid, simple, two-step test for the detection of ovulation has been developed. The test is based on ELISA of pregnanediol glucuronide, a metabolite of progesterone, in urine collected specifically over a period of 3 h. The test is completed in 20 min and the results are assessed visually by naked eye.

Excretion of estrone-3-glucuronide in urine in spontaneous and induced ovulatory cycles

Response of the ovary to ovulation-inducing agents, such as clomiphene citrate and gonadotropin, was assessed using estimations of urinary estrone-3-glucuronide (E1G) by an ELISA test. Baseline data collected over 58 cycles from regularly menstruating women were used as reference. Further, the pattern of E1G excretion was compared with ultrasound assessment of follicular growth. In ovulatory cycles, a good correlation is seen between follicular growth and follicular function. However, when cystic follicles develop after treatment, the correlation is poor: the follicle increases in size without a corresponding increase in E1G excretion. It is suggested that ultrasound examination and hormonal pattern should be used concurrently to assess the response of the ovary to ovulation-inducing agents.

Application of penicillinase linked ELISA of pregnanediol glucuronide for detection of ovulation and assessment of corpus luteal function

A penicillinase linked enzyme immunoassay was developed for the estimation of pregnanediol-3 alpha-glucuronide (PdG) in urine. The immunoassay satisfied all the validity criteria and was used in detecting ovulation and in the assessment of corpus luteal function (CLF) during spontaneous or induced cycles. Reference values were established by estimating PdG levels in daily early morning urine samples during 31 menstrual cycles obtained from 17 regularly menstruating women. A PdG value of 1.7 micrograms/mg creatinine (micrograms/mgC) (90th Centile of follicular phase) in any MLP (mid-luteal phase) sample was considered as indicating ovulation. A value of 4.6 micrograms/mgC (20th centile of MLP) was considered to be evidence of sufficient CLF. When this approach was applied to 20 infertile cases, detection of the occurrence of ovulation/anovulation was made correctly in 19 out of 20 cases (95%). Accuracy was poor (55.6%) when the aim of the diagnosis was corpus luteal deficiency. Higher accuracy (88.9%) for corpus luteal deficiency/corpus luteal adequacy was obtained when the sum of PdG concentrations in three MLP samples were taken into consideration. A total of 13.8 micrograms/mgC (thrice the 20th centile for MLP) indicated probable corpus luteal deficiency, and values above this limit were considered to indicate corpus luteal adequacy.