Bone mineral density, vertebral fractures and trabecular bone score in primary ovarian insufficiency

PURPOSE

Bone health in primary ovarian insufficiency (POI) is under-investigated. We assessed patients with spontaneous POI for vertebral fractures (VFs) and related parameters of bone health.

METHODS

70 cases with spontaneous POI (age 32.5 ± 7.0 years) and an equal number of controls were assessed for BMD, TBS, and VFs. BMD at the lumbar-spine (L1-L4), left hip, non-dominant forearm, and TBS (iNsight software) were measured on a dual-energy X-ray absorptiometry (DXA) machine. VFs were assessed by Genant's classification. Serum FSH, LH, estradiol, T4, TSH, iPTH, serum 25(OH)D, total calcium, and inorganic phosphorus were measured.

RESULTS

BMD at the lumbar-spine, hip and forearm was reduced by 11.5%, 11.4% and 9.1% in POI as compared to controls (P < 0.001). Degraded or partially degraded microarchitecture on TBS was observed in 66.7% of patients and 38.2% of controls (P = 0.001). 15.7% of the POI patients had VFs, compared to 4.3% of controls (P = 0.045). Age, duration of amenorrhea and duration of HRT use were the significant predictors of TBS (P < 0.01). Serum 25(OH)D was the significant determinant of VFs. TBS abnormalities were higher in patients with POI and VFs. BMD was not significantly different in patients with and without VFs.

CONCLUSION

Thus, lumbar-spine osteoporosis, impaired TBS and VFs were present in 35.7%, 66.7% and 15.7% of patients with spontaneous POI in their early third decade. This indicates need for rigorous investigations for impaired bone health in these young patients and management with HRT, vitamin-D, and possible need for bisphosphonate therapy.

Screening for cardiac allograft rejection among heart transplant recipients using an electrocardiogram-based deep learning model

Background

Current approaches utilizing non-invasive methods to screen for cardiac allograft rejection (gene expression profiling and cell free DNA) have yet to be broadly integrated into heart transplant management and have shown limited discrimination (AUCs of 0.68 and 0.77, respectively). Changes in the electrocardiogram (ECG) have been reported at the time of severe cardiac rejection, including low voltages and conduction abnormalities. It remains unknown if subtle ECG changes correlating with cardiac allograft rejection can be detected earlier using machine learning methods.

Purpose

We sought to develop an artificial intelligence (AI) model to detect cardiac allograft rejection based on the 12 lead ECG.

Methods

We identified all patients who underwent a heart transplant at 3 hospital sites within a single health system from Jan 1998 through Apr 2021 and extracted digital 12-lead ECG data as well as endomyocardial biopsy pathology results from the electronic medical record. We partitioned our data into a training (80%), validation (10%), and test set (10%) based on a group stratification sampling. Each patient was present in only one set and each set had a positivity rate of 2.6% with 6,074/758/758 ECGs belonging to 1,146/140/141 unique patients in each set respectively. Cardiac allograft rejection was defined as moderate or severe acute cellular rejection based on International Society for Heart and Lung Transplantation (ISHLT) guidelines. A convolutional neural network, using the 12-lead ECG data as input, was trained with hyperparameter optimization for regularization, learning rate adjustments, and class weights. Model performance metrics were based on the test data and estimated using the final model architecture.

Results

1,587 heart transplant recipients who had at least one endomyocardial biopsy were evaluated for inclusion. We limited our sample to ECGs performed within 30 days of the biopsy date (7,590 ECGs, representing 1,425 unique patients). Our study population had a median age of 55.8 years and 28.7% were female. The median number of ECG-biopsy pairs per patient was 5. The majority of endomyocardial biopsy results were classified as none or mild rejection (97.1%), and 2.9% had moderate/severe rejection. The ECG-based AI model detected cardiac allograft rejection with an area under the receiver operative curve (AUC) of 0.84 in the test set. The sensitivity, specificity, positive and negative predictive values were 95%, 52.6%. 5.2% and 99.7% respectively.

Conclusions

An AI-ECG model appears to outperform novel non-invasive laboratory tests (gene expression profiling and cell free DNA) for detecting cardiac allograft rejection and does not require a blood draw or the additional complexities surrounding sample processing. This model relies on a readily available and relatively inexpensive test, the ECG. In addition, AI predictions can be made available within a few minutes following ECG acquisition.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): Mayo Clinic

Vertebral fractures, trabecular bone score and their determinants in chronic hypoparathyroidism

PURPOSE

Patients with hypoparathyroidism are at risk of vertebral fractures (VFs) despite high bone mineral density (BMD). We investigated this paradox by assessing trabecular bone score (TBS) and hip structural analysis (HSA) in non-surgical chronic hypoparathyroidism (cHypoPT) with and without VFs.

METHODS

152 cHypoPT patients (age 40.2 ± 13.4 years, M: F = 81:71) with a median follow-up of 8 (2-13) years were assessed for BMD, VFs, TBS, and HSA and compared with 152 healthy controls. VFs at T₇-L₄ were assessed by Genant's method. Average serum total calcium and phosphorus during follow-up were assessed.

RESULTS

The lumbar spine and hip BMD were higher by 25.4 and 13.4% in cHypoPT than controls (P < 0.001). Paradoxically, VFs (30.9 vs.7.9%), including multiple (12.5 vs. 2.6%) were higher in cHypoPT (P < 0.001). Though overall average TBS (1.411 ± 0.091) was normal in cHypoPT, 25.4% of the females had subnormal TBS, more in post than pre-menopausal women (52.3 vs. 14%, P = 0.002) and as compared to males (6.1%, P = 0.001). TBS correlated with menopausal status and follow-up serum calcium-phosphorus product. For every gm/cm² rise in BMD, TBS increase was only 0.227 in cHypoPT compared to 0.513 in controls. Frequency of VFs increased with declining TBS (P = 0.004). HSA was comparable between cHypoPT with and without VFs. 23.4% of cHypoPT with VFs had subnormal TBS.

CONCLUSION

31% of cHypoPT patients had VFs. TBS indicated degraded bone microarchitecture in 50% of the post-menopausal cHypoPT women. However, TBS has limitations to detect abnormal bone microarchitecture in cHypoPT as only one-fourth of patients with VFs showed low TBS.

The First Reported Case of COVID-19 Myocarditis Managed with Biventricular Impella Support

Introduction

SARS-CoV-2, responsible for COVID-19, is a pandemic that has taken the world by storm. We present the only contemporary reported case of COVID-19 myocarditis leading to recovery with utilization of biventricular impella for temporary mechanical circulatory support. No cases have been reported regarding utilization of Bi-V impella as therapy for management of SARS-CoV-2..

Case Report

We present a 35 year old-woman with history of systemic sclerosis who was found to have 5 days of generalized malaise associated with fevers and cough. On arrival she was found tachycardic at 112 bpm and febrile 101.8 F. She tested positive for COVID-19 via nasal CPR. Cardiac enzymes were found elevated on admission with troponin T elevated at 0.28. On day two of hospitalization patient had spontaneous PEA arrest secondary to hypoxemia. Transthoracic echocardiogram(TTE) revealed EF <10% and RV impairment which compare to prior which had normal ejection fraction. Labs showed elevated lactic acidosis of 10. Invasive hemodynamics assessment RA 21 mmHg, PA 32/23(mean 26 mmHg) and PCWP 18 mmHg. Calculated PAPi 0.76, CO 2.1 L/min and CI of 1.2 L/min/m^2. Decision was made to place right and left sided ventricular impellas for mechanical circulatory support. She was started on IVIG for COVID-19 myocarditis along with remdesivir and solumedrol. After two weeks of continuous temporary mechanical circulatory support(TMCS), patient hemodynamics improved and she was able to be weaned from her need for TMCS. Repeat echocardiogram demonstrated recovery and remodeling with an LVEF of 60% and no significant valvular disease. She was discharge home at day 23 with no neurological deficit.

Summary

The use of biventricular continuous microaxial flow devices during acute COVID-19 myocarditis is key to allow ventricular rest and optimal offloading without the increased risk of surgically placed TMCS such as Centrimag or VA or VV ECMO. With recent emergency use by the FDA, its wide adaptation remains sparse. Our case demonstrates a unique approach to management of COVID-19 myocarditis. It is the only reported case in the literature utilizing biventricular Impella devices for circulatory support without the concurrent use of ECMO. Due to the success in this patient, this promising approach warrants continued investigation in the management of COVID myocarditis and cardiogenic shock.

Mechanical properties of cell- and microgel bead-laden oxidized alginate-gelatin hydrogels

3D-printing technologies, such as biofabrication, capitalize on the homogeneous distribution and growth of cells inside biomaterial hydrogels, ultimately aiming to allow for cell differentiation, matrix remodeling, and functional tissue analogues. However, commonly, only the mechanical properties of the bioinks or matrix materials are assessed, while the detailed influence of cells on the resulting mechanical properties of hydrogels remains insufficiently understood. Here, we investigate the properties of hydrogels containing cells and spherical PAAm microgel beads through multi-modal complex mechanical analyses in the small- and large-strain regimes. We evaluate the individual contributions of different filler concentrations and a non-fibrous oxidized alginate-gelatin hydrogel matrix on the overall mechanical behavior in compression, tension, and shear. Through material modeling, we quantify parameters that describe the highly nonlinear mechanical response of soft composite materials. Our results show that the stiffness significantly drops for cell- and bead concentrations exceeding four million per milliliter hydrogel. In addition, hydrogels with high cell concentrations (≥6 mio ml^-1) show more pronounced material nonlinearity for larger strains and faster stress relaxation. Our findings highlight cell concentration as a crucial parameter influencing the final hydrogel mechanics, with implications for microgel bead drug carrier-laden hydrogels, biofabrication, and tissue engineering.

Polyacrylamide Bead Sensors for in vivo Quantification of Cell-Scale Stress in Zebrafish Development

Mechanical stress exerted and experienced by cells during tissue morphogenesis and organ formation plays an important role in embryonic development. While techniques to quantify mechanical stresses in vitro are available, few methods exist for studying stresses in living organisms. Here, we describe and characterize cell-like polyacrylamide (PAAm) bead sensors with well-defined elastic properties and size for in vivo quantification of cell-scale stresses. The beads were injected into developing zebrafish embryos and their deformations were computationally analyzed to delineate spatio-temporal local acting stresses. With this computational analysis-based cell-scale stress sensing (COMPAX) we are able to detect pulsatile pressure propagation in the developing neural rod potentially originating from polarized midline cell divisions and continuous tissue flow. COMPAX is expected to provide novel spatio-temporal insight into developmental processes at the local tissue level and to facilitate quantitative investigation and a better understanding of morphogenetic processes.

Standardized microgel beads as elastic cell mechanical probes

Cell mechanical measurements are gaining increasing interest in biological and biomedical studies. However, there are no standardized calibration particles available that permit the cross-comparison of different measurement techniques operating at different stresses and time-scales. Here we present the rational design, production, and comprehensive characterization of poly-acrylamide (PAAm) microgel beads mimicking size and overall mechanics of biological cells. We produced mono-disperse beads at rates of 20-60 kHz by means of a microfluidic droplet generator, where the pre-gel composition was adjusted to tune the beads' elasticity in the range of cell and tissue relevant mechanical properties. We verified bead homogeneity by optical diffraction tomography and Brillouin microscopy. Consistent elastic behavior of microgel beads at different shear rates was confirmed by AFM-enabled nanoindentation and real-time deformability cytometry (RT-DC). The remaining inherent variability in elastic modulus was rationalized using polymer theory and effectively reduced by sorting based on forward-scattering using conventional flow cytometry. Our results show that PAAm microgel beads can be standardized as mechanical probes, to serve not only for validation and calibration of cell mechanical measurements, but also as cell-scale stress sensors.

Shoulder Periarthritis and its Imaging Features in Patients with Type 1 Diabetes Mellitus

Aim: There is limited information on periarthritis/adhesive capsulitis of the shoulder (ACS) in patients with type-1-diabetes mellitus (T1D). We assessed the prevalence and characteristics of ACS in patients with type-1-diabetes mellitus.

Methods: Consecutive 267 patients attending 'Diabetes of Young Clinic' were screened for ACS. Those with clinical features of ACS were further assessed by 'shoulder pain and disability index' (SPADI), radiograph and MRI of the shoulder. The average glycemic status (HbA1c) during preceding 2 years was assessed in patients with and without ACS. Controls were age and sex matched healthy subjects (1:1 ratio).

Results: Sixteen of 267 patients (6.0%) with type-1-diabetes had clinical features of ACS, unlike none of the healthy controls (P < 0.001). Internal and external rotation of the shoulders was the most frequently restricted movements in ACS. Thickened coracohumeral ligament and axillary pouch obliteration was characteristic MRI feature, present in 80.0% in 73.3% cases, respectively. Though 14/16 type-1-diabetes patients with ACS were symptomatic, they never reported these complaints in diabetic clinic with the treating physicians. On regression analysis (odds ratio; 95% CI), duration of diabetes (1.1; 1.03-1.17, P < 0.01), retinopathy (3.6; 1.05-12.52, P = 0.04), and limited joint mobility (6.4; 1.88-21.95, P < 0.01) were independent predictors for presence of ACS in type-1-diabetes. The mean HbA1c and lipid levels were comparable in patients with or without ACS.

Conclusions: Six percent of patients with type-1-diabetes had ACS, which can be detected on clinical screening and confirmed by imaging to help initiate early treatment.

Fatigue-Assisted Grain Growth in Al Alloys

Stress-assisted grain growth at room temperature is known for materials with nanocrystalline grains. For larger grain sizes, the grain growth usually takes place at higher homologous temperatures even under stress. Here we report, for the first time, significant grain growth at room temperature under fatigue loading in microcrystalline grains (≥10 μm) in Al 7075. We demonstrate that this grain growth at room temperature is similar to non-uniform grain growth due to grain rotation and coalescence rather than the thermally and the stress-assisted driven grain growth. We show that the grain growth is associated with the formation of a strong near-Cu {112}<111> texture component as a result of fatigue-assisted deformation. These changes in microstructural features (viz., grain size, grain orientations and texture) are fundamentally important in understanding the cyclic crack induced deformation behavior and for predicting the fatigue lifetime in structural materials.

Infections in infancy and the presence of antinuclear antibodies in adult life

There has been limited success defining environmental factors important to the development of connective tissue diseases such as systemic lupus erythematosus (SLE). Recent work has suggested that the perinatal environment may be important. To investigate this we measured antinuclear antibodies (ANA) in a general population with well-defined early lives to see whether fetal and infant growth and infections were associated with ANA positivity in adult life. Included in our investigation were 1334 individuals (668 men, 666 women) from the Hertfordshire cohort study. ANA was measured using an ANA ELISA and confirmed using immunofluorescence. We investigated associations between the presence of ANA and early growth and infectious exposure in infancy in men and women combined, but with adjustment for gender throughout. A positive ANA was present in 73 (10.9%) of men and 81 (12.2%) women. Of these, 26 women and 14 men were positive using IF on HEP2 cells. Sharing a bedroom during childhood was associated with a higher risk of being ANA positive (odds ratio (OR), 1.42, 95% confidence interval (CI) 1.00-2.01, P = 0.05). A record of diarrhoeal illness (OR 2.12 95% CI 1.07, 4.23, P = 0.03) and rubella or mumps during the first year of life (OR 16.12, 95% CI 2.92, 88.94, P = 0.001) was also significantly associated with ANA in adult life. Higher ANA titres by Inova ELISA were associated with infections in the first year of life from mumps (2.74-fold higher, 95% CI 0.98, 7.64, P = 0.05) and rubella (3.90-fold higher, 95% CI 1.89, 8.04, P < 0.001). In addition, higher ANA titres were also associated with mumps (1.26-fold higher, 95% CI 1.02, 1.56, P = 0.03) between one and five years of age. Our results suggest that a developing immune system exposed to increased infection is more likely to produce ANA in adult life and perhaps begin the pathological process that leads to SLE.

Frontotemporal correlates of impulsivity and machine learning in retired professional athletes with a history of multiple concussions

The frontotemporal cortical network is associated with behaviours such as impulsivity and aggression. The health of the uncinate fasciculus (UF) that connects the orbitofrontal cortex (OFC) with the anterior temporal lobe (ATL) may be a crucial determinant of behavioural regulation. Behavioural changes can emerge after repeated concussion and thus we used MRI to examine the UF and connected gray matter as it relates to impulsivity and aggression in retired professional football players who had sustained multiple concussions. Behaviourally, athletes had faster reaction times and an increased error rate on a go/no-go task, and increased aggression and mania compared to controls. MRI revealed that the athletes had (1) cortical thinning of the ATL, (2) negative correlations of OFC thickness with aggression and task errors, indicative of impulsivity, (3) negative correlations of UF axial diffusivity with error rates and aggression, and (4) elevated resting-state functional connectivity between the ATL and OFC. Using machine learning, we found that UF diffusion imaging differentiates athletes from healthy controls with significant classifiers based on UF mean and radial diffusivity showing 79–84 % sensitivity and specificity, and 0.8 areas under the ROC curves. The spatial pattern of classifier weights revealed hot spots at the orbitofrontal and temporal ends of the UF. These data implicate the UF system in the pathological outcomes of repeated concussion as they relate to impulsive behaviour. Furthermore, a support vector machine has potential utility in the general assessment and diagnosis of brain abnormalities following concussion.

Performance evaluation of a dynamic telepathology system (Panoptiq™) in the morphologic assessment of peripheral blood film abnormalities

INTRODUCTION

The study evaluated the performance of a dynamic imaging telepathology system (Panoptiq(™) ) as a diagnostic aid to the identification of peripheral blood film (PBF) abnormalities.

METHODS

The study assumed a laboratory personnel working in a clinical laboratory were operating the telepathology system to seek diagnostic opinion from an external consulting hematopathologist. The study examined 100 blood films, encompassing 23 different hematological diseases, reactive or normal cases.

RESULTS

The study revealed that with real-time image transmission in live scanning mode of operation, the telepathology system was able to aid reviewers in achieving excellent accuracy, that is correct interpretation of morphologic abnormalities obtained in 83/84 of the hematologic diseases and 12/12 of the reactive/normal conditions (Sensitivity: 0.99; Specificity: 1.00). In contrast, when only saved static images in digital capture mode of operation were reviewed remotely, interpretative omissions occurred in 8/84 of the hematologic diseases and 0/12 of the reactive/normal conditions (Sensitivity: 0.91; Specificity: 1.00). It is hypothesized that real-time operator-reviewer communication during live scanning played an important role in the identification of key morphologic abnormalities for review.

CONCLUSION

Our study showed the Panoptiq system can be adopted reliably as a dynamic telepathology tool in aiding community laboratories in the triage of PBF cases for external diagnostic consultation.

Potential contribution of monoamine oxidase a gene variants in ADHD and behavioral co-morbidities: scenario in eastern Indian probands

Attention deficit hyperactivity disorder (ADHD) is the most frequently diagnosed behavioral disorder in children with a high frequency of co-morbid conditions like conduct disorder (CD) and oppositional defiant disorder (ODD). These traits are controlled by neurotransmitters like dopamine, serotonin and norepinephrine. Monoamine oxidase A (MAOA), a mitochondrial enzyme involved in the degradation of amines, has been reported to be associated with aggression, impulsivity, depression, and mood changes. We hypothesized that MAOA can have a potential role in ADHD associated CD/ODD and analyzed 24 markers in a group of Indo-Caucasoid subjects. ADHD probands and controls (N = 150 each) matched for ethnicity and gender were recruited following the Diagnostic and Statistical Manual for Mental Disorders-IV. Appropriate scales were used for measuring CD and ODD traits. Markers were genotyped by PCR-based methods and data obtained analyzed using the Cocaphase program under UNPHASED. Only eight markers were found to be polymorphic. rs6323 "G" allele showed higher frequencies in ADHD (P = 0.0023), ADHD + CD (P = 0.03) and ADHD + ODD (P = 0.01) as compared to controls. Haplotype analysis revealed statistically significant difference for three haplotypes in ADHD cases (P < 0.02). Statistically significant differences were also noticed for haplotypes in ADHD + CD and ADHD + ODD cases (P < 0.01). LD analysis showed significant variation in different groups. Multidimensionality reduction analysis showed independent as well as interactive effects of markers. Genotypes showed correlation with behavioral problems in ADHD and ADHD + CD. We interpret that MAOA gene variants may contribute to the etiology of ADHD as well as associated co-morbid CD and ODD in this ethnic group.

Exchange bias of the interface spin system at the Fe/MgO interface

The ferromagnet/oxide interface is key to developing emerging multiferroic and spintronic technologies with new functionality. Here we probe the Fe/MgO interface magnetization, and identify a new exchange bias phenomenon manifested only in the interface spin system, and not in the bulk. The interface magnetization exhibits a pronounced exchange bias, and the hysteresis loop is shifted entirely to one side of the zero field axis. However, the bulk magnetization does not, in marked contrast to typical systems where exchange bias is manifested in the net magnetization. This reveals the existence of an antiferromagnetic exchange pinning layer at the interface, identified here as FeO patches that exist even for a nominally 'clean' interface. These results demonstrate that atomic moments at the interface are non-collinear with the bulk magnetization, and therefore may affect the net anisotropy or serve as spin scattering sites. We control the exchange bias magnitude by varying the interface oxygen concentration and Fe-O bonding.

Risk and outcome of multidrug-resistant tuberculosis: vitamin D receptor polymorphisms and serum 25(OH)D

SETTING

All India Institute of Medical Sciences and Rajan Babu Institute of Pulmonary Medicine and Tuberculosis, New Delhi, India.

OBJECTIVE

To investigate the association of vitamin D receptor (VDR) polymorphisms and serum 25(OH)D with susceptibility to, and response to treatment of, multidrug-resistant tuberculosis (MDR-TB) in comparison with drug-susceptible pulmonary TB (DS-PTB) and healthy controls.

DESIGN

Cross-sectional study.

METHODS

A total of 897 participants from northern India were consecutively enrolled into three groups (MDR-TB 354, DS-PTB 338, controls 205). Genotypic and allelic frequencies of FokI, BsmI and TaqI VDR polymorphisms, and serum 25(OH)D, calcium and intact parathyroid hormone were measured in all participants. In those with active TB, disease severity, time to sputum smear and culture conversion were correlated with VDR genotype and biochemical parameters.

RESULTS

FokI Ff genotype and TaqI t allele correlated positively with MDR-TB; Ff genotype and f allele of FokI frequency were higher in both TB groups. BsmI Bb genotype correlated inversely with MDR-TB. Serum 25(OH)D concentrations were significantly lowest in MDR-TB, correlating inversely with time to sputum smear conversion.

CONCLUSIONS

VDR gene polymorphisms and hypovitaminosis D may predispose to MDR-TB. Lower serum 25(OH)D may increase time to MDR-TB sputum smear negativity.

Physicians' attitudes towards self-treatment of latent tuberculosis

We conducted a cross-sectional study to assess physicians' attitudes towards self-treatment of latent tuberculosis infection (LTBI) based on real-time responses related to actual purified protein derivative (PPD) results, in addition to using hypothetical situations for those who were PPD-negative. We also obtained information on physicians' recommendations for their patients to treat this condition. Although the physicians claimed to recommend optimal treatment to their patients, the majority of them had different attitudes when considering treatment for themselves. There appears to be a discrepancy between physicians' attitudes to self-treatment and their management of patients with LTBI.

Myogenic activity in autoregulation during low frequency oscillations

Lower body negative pressure (LBNP) was applied in eight human subjects to trigger low frequency oscillations in order to study the nature of functional coupling between the hemodynamic and autonomic nervous systems, with particular focus on how the myogenic response fits within this coupling. To this end muscle sympathetic nerve activity (MSNA), mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), and total peripheral resistance (TPR) were measured at baseline and during LBNP and were then examined in both the time and frequency domains. At the height of low frequency oscillations (~0.1Hz) there was a strong coupling between all the five indices, marked by perfect alignment of their oscillatory frequencies. Results in the time domain show that a fall in MAP is followed by a fall in TPR at 1.58s SD 0.69), a rise in heart rate at 2.64s (SD 0.98), a rise in cardiac output at 3.72s (SD 0.60), a peak in MSNA at 5.71s (SD 1.27) and, finally, a rise in TPR at 7.13s (SD 1.02). A possible interpretation of the latter is that a drop in MAP first triggers a drop in TPR via a myogenic response before the expected rise in TPR via a rise in MSNA. In other words, following a drop in arterial pressure, myogenic response controls vessel diameter before this control is taken over by MSNA. These findings provide a possible resolution of a longstanding conceptual argument against attributing a significant role for the myogenic response in blood flow autoregulation.

Presence of 25(OH) D deficiency in a rural North Indian village despite abundant sunshine

BACKGROUND AND OBJECTIVE

Several studies have shown wide prevalence of vitamin D deficiency with serum 25(OH)D <49.9 nmol/L in urban Indians related to their poor sunshine exposure and skin pigmentation. However, there is limited information in rural Indians. We hypothesized presence of higher 25(OH)D in rural subjects as compared to urban because of farming related abundant sunshine exposure.

DESIGN AND METHODS

We assessed serum 25(OH)D levels in residents of a North Indian village with 200 families, located 90 km East of Delhi during February (winter). Fifty seven subjects (32 males and 25 females) from 50 families consented for the study.

RESULTS

The mean 25(OH)D values of all subjects in the rural area was 36.4 +/- 22.5 nmol/l/L. Males had significantly higher 25(OH)D values than females. When compared to urban subjects, the mean 25(OH)D value of rural males and females was six and three folds higher, respectively. However even with five hours of daily sunshine exposure only 31.5% had serum 25(OH)D levels > or = 50 nmol/L.

CONCLUSIONS

Thus, with longer sunshine exposure subjects residing in rural area had better mean 25(OH)D values than that of urbans. However, 70% of them were still vitamin D deficient. These facts indicate the need for the countrywide vitamin D food fortification program irrespective of rural or urban setting.

Prevalence & potential significance of vitamin D deficiency in Asian Indians

Studies from our center and other parts of India have drawn attention towards wide prevalence of vitamin D deficiency (VDD) in our country. VDD has been reported in all age groups including toddlers, school children, pregnant women and their neonates and adult males and females residing in rural and urban India. We reviewed implications of VDD in our population based on the preliminary data available from Indian studies on skeletal health. Besides, a brief review is made on the importance of VDD in various other disorders prevalent in equivalent proportions among Indians such as type 2 diabetes mellitus (DM), cardiovascular diseases (CVD), immune competence including relation to tuberculosis, malignancy and osteoarthritis. Data from the West have also associated VDD with increased prevalence of type 2DM, CVD, autoimmune disorders, tuberculosis, prostate, breast and colon malignancy and osteoarthritis. Such association has not been studied to date in our country. Overall results of various studies conducted to date in urban and rural Indians indicate that widely prevalent VDD is functionally relevant to skeletal health including osteomalacia and rickets. However, there is a need to explore its association with osteoporosis related fractures and various other non skeletal disorders linked with VDD.

The presence of anticardiolipin antibodies in adults may be influenced by infections in infancy

OBJECTIVES

There has been limited success defining environmental factors important in the development of antiphospholipid (Hughes) syndrome (APS). Recent work suggests that the perinatal environment may be important in the development of other autoimmune diseases. We measured anticardiolipin antibodies (aCL) in a general population with well-defined early lives to see whether fetal and infant growth and infections were associated with aCL positivity in adult life.

METHODS

aCLs were measured using an ELISA in 1384 individuals from the Hertfordshire cohort study. We investigated associations between the presence of aCL and early growth and infectious exposure in infancy in men and women.

RESULTS

ELISA positive aCL (IgM and IgG) was present in 22 (3%) men and 15 (2%) women. Using the highest octile of aCL results, in men higher birth weight (per lb of birth weight: OR 1.18, 95% CI 1.02-1.36, P = 0.02) and diarrhoeal infection in the first year of life (OR 2.55, 95% CI 1.10, 5.92, P = 0.03) were associated with an increased likelihood of being aCL positive. In women, diarrhoeal infection in the first year of life was also associated with an increased likelihood of aCL positivity (OR 2.23, 95% CI 1.01, 4.91, P = 0.05). For IgG titre in men, significant relationships were found with sharing a bedroom (regression coefficient 1.13; 95% CI 1.05, 1.22; P = 0.02) and diarrhoea in the first year (coefficient 1.25; 95% CI 1.00, 1.56; P = 0.05).

CONCLUSION

A developing immune system when exposed to the infectious environment may influence the likelihood of producing aCL in adult life.

Role of virulence plasmid of Aeromonas hydrophila in the pathogenesis of ulcerative disease syndrome in Clarias batrachus

Pathogenic Aeromonas hydrophila (strain VB21), a multiple-drug resistance strain contains a plasmid of about 21 kb. After curing of plasmid, the isolates became sensitive to antimicrobials, to which they were earlier resistant. The cured bacteria exhibited significant alterations in their surface structure, growth profile and virulence properties, and failed to cause ulcerative disease syndrome (UDS) when injected into the Indian catfish Clarias batrachus. Routine biochemical studies revealed that the plasmid curing did not alter the biochemical properties of the bacteria. After transformation of the plasmid into cured A. hydrophila the bacterium regained its virulence properties and induced all the characteristic symptoms of UDS when injected into fish. Thus, the plasmid plays a pivotal role in the phenotype, growth and virulence of A. hydrophila and pathogenesis of aeromonad UDS.

Association and interaction of the TNF-alpha gene with other pro- and anti-inflammatory cytokine genes and HLA genes in patients with type 1 diabetes from North India

Type 1 diabetes (T1D) is a multifactorial autoimmune disorder where major histocompatibility complex (MHC) genes and the insulin-linked polymorphic region have been shown to play major roles. We report here an integrated effect of tumor necrosis factor (TNF) alpha with other cytokine genes. The TNF-alpha-308 GA and AA (high secretor) polymorphisms were significantly increased in the patients with T1D (n = 235) [P < 7 x 10(-6), odds ratio (OR) = 3.04, 95% confidence interval (CI) = 1.8-5.3] compared with the controls (n= 128). The variants of interferon-gamma (IFN-gamma) (A(+874)T), interleukin (IL)-6 (G(-174)C), IL-10 (A(-1082)G, T(-819)C, C(-592)A) and transforming growth factor (TGF) beta1 (T(cdn10)C, G(cdn25)C) did not show a significant difference between patients and controls. However, simultaneous presence of TNF-alpha-308 GA+AA along with both high and low secretor genotypes of IFN-gamma (P < 0.003) was significantly increased in patients. Simultaneous presence of TNF-alpha-308 GA + AA along with high secretor genotypes of IL-6 (P < 0.0001, OR = 2.61, 95% CI = 1.5-4.56), IL-10 (P < 0.0001, OR = 4.26, 95% CI = 1.9-10.1) and TGF-beta1 (P < 0.00004, OR = 2.8, 95% CI = 1.6-4.86) was also significantly increased in patients with T1D. Low secretor genotype of TNF-alpha-308 GG along with low secretor genotypes of IFN-gamma (P < 0.001, OR = 0.465, 95% CI = 0.28-0.77), high secretor genotypes of IL-6 (P < 0.000004, OR = 0.76, 95% CI = 0.227-0.621) and TGF-beta1 (P < 0.000006, OR = 0.336, 95% CI = 0.198-0.568) was protective. The TNF-alpha-308 G allele was in linkage disequilibrium (LD) with the human leukocyte antigen (HLA)-B*0801-DRB1*0301 haplotype, while TNF-alpha-308 A allele was in LD with the HLA-B*5001-DRB1*0301 and B*5801-DRB1*0301 haplotypes, suggesting that the effect of TNF-alpha -308 A allele is not because of its being in LD with any HLA alleles, but because of its functional role and its integrated effect with other cytokines.

Sex differences in the effect of prepubertal GALP infusion on growth, metabolism and LH secretion

The hypothalamic neuropeptide, galanin-like peptide (GALP), is known to have an effect on energy expenditure and reproduction in adult male rats, but little work has been done on prepubertal rats. We hypothesized that hypothalamic GALP is involved in physiological changes associated with the onset of puberty. To test this hypothesis, we first determined the postnatal ontogeny of GALP gene expression via in situ hybridization of developing male and female rat pups through adulthood. GALP gene expression was not observed in either male or female rat pups until after postnatal day (PND) 10 and did not reach adult-like levels until after weaning (PND25). To determine if exogenous GALP could induce the onset of puberty, PND25 male and female rats were implanted with lateral ventricular cannulas connected to an osmotic minipump that delivered either GALP or vehicle. GALP infusion significantly (p<0.05) increased body weight, food intake, and metabolic rate in male but not female rats compared to control infusion. After 2 weeks, GALP infusion had no significant effect on the onset of puberty, percent body fat, nor plasma levels of insulin, FSH or gonadal steroids in either sex; however, GALP did significantly (p<0.05) increase plasma levels of LH and leptin in male but not female rats and increased plasma growth hormone (GH) in both sexes. Our observations further demonstrate a sex difference in GALP responsiveness in prepubertal rats. These data suggest that GALP may be involved with the prepubertal increase in circulating leptin, LH, and GH resulting in an increase in metabolic rate and lean growth associated with puberty.

The autoantibody rheumatoid factor may be an independent risk factor for ischaemic heart disease in men

BACKGROUND

Subjects with rheumatoid arthritis have an increased prevalence of ischaemic heart disease (IHD). This is most likely in those people with the autoantibody rheumatoid factor (RF). RF is strongly associated with rheumatoid arthritis (RA) but is also present in up to 15% of all adults.

OBJECTIVE

To determine whether RF might identify people in a general population who also share an increased likelihood of developing IHD.

METHODS

Subjects from the Hertfordshire Cohort Study were investigated for the presence of RF. Subjects completed a questionnaire and attended a clinic where a history of IHD was recorded (ECG, coronary artery bypass grafting, Rose chest pain). Associations between the presence of RF, antinuclear antibodies (ANA), anticardiolipin antibodies (ACA) and IHD in 567 men and 589 women were investigated and compared with traditional risk factors for IHD.

RESULTS

RF was associated with an increased likelihood of IHD in men (odds ratio (OR) = 3.1, 95% CI 1.7 to 5.4, p<0.001). This increased risk could not be explained by traditional risk factors for IHD (mutually adjusted OR for RF 2.9 (95% CI 1.6 to 5.3), p<0.001). There was no significant association between RF in women or between ANA or ACA with IHD in men or women.

CONCLUSION

This work suggests that RF is an independent risk factor for IHD in the general population. It lends support to the importance of inflammation in atherosclerosis and suggests that autoimmune processes may be involved. In addition, it raises the intriguing possibility that RF may have a direct role in the pathogenesis of IHD in some subjects.

Role of vascular bed compliance in vasomotor control in human skeletal muscle

The current view of neurogenic vasomotor control in skeletal muscle is based largely on changes in vascular bed resistance. The purpose of this study was to determine to what extent vascular bed compliance may also play a role in this regulation. For this purpose, pressure waveforms (Millar and Finometer) and flow waveforms (Doppler ultrasound) were measured simultaneously in the brachial artery of seven healthy individuals during physiological manoeuvres which were expected to produce non-neurogenic changes in resistance (wrist-cuff occlusion; n = 5) or compliance (arm elevation; n = 6) of the forearm vascular bed. Vascular resistance (R) was calculated from the average flow and pressure values. A lumped Windkessel model was used to obtain vascular bed compliance (C) from these concurrently measured waveforms. Compared with baseline (3.81 +/- 1.59 ml min(-1) mmHg(-1)), wrist occlusion increased R (65 +/- 75%; P < 0.05) with minimal change in C (-15 +/- 16%; n.s.). Compared with the arm in neutral position (0.0075 +/- 0.003 ml mmHg(-1)), elevation of the arm above heart level produced a 86 +/- 41% increase in C (P < 0.05) with little change in R (-5 +/- 11%). In addition, neurogenic changes were assessed during lower body negative pressure (LBNP) and a cold pressor test (CPT; n = 7). Lower body negative pressure induced a 29 +/- 24% increase in R and a 26 +/- 12% decrease in C (both P < 0.05). The CPT induced no consistent change in R but a 22 +/- 7% reduction in C (P < 0.05). It was concluded that vascular bed compliance is an independent variable which should be considered along with vascular bed resistance in the mechanics of vasomotor regulation in skeletal muscle.