Malignant Insulinoma Arising From Nonfunctioning Pancreatic Neuroendocrine Tumor

Pancreatic neuroendocrine tumors are rare neoplasms characterized into nonfunctioning (NF-PNET) and functioning (F-PNET) subtypes. F-PNETs typically involve overt symptoms related to excessive hormone secretion but may rarely present first as NF-PNETs with delayed transformation. We present a patient with known NF-PNET with liver metastases who developed hypoglycemia 2 years after initial diagnosis due to malignant insulinoma. Hypoglycemia was refractory to continuous dextrose but improved temporarily after diazoxide and hepatic artery embolization. Malignant insulinomas are usually metastatic at presentation and portend poor prognosis. Hypoglycemia may be medically managed with steroids, somatostatin analogues, and diazoxide, along with therapies to reduce tumor burden.

ODP315 Hypoglycemia: Neuroendocrine Tumor of the Pancreas with Liver Metastasis and Transformation to Insulinoma

Background

Neuroendocrine tumors (NETs) are rare, can be found in any part of the body including the gastrointestinal tract, lung, and pancreas and have potential for metastasis.

Clinical Case

A 39-year-old male with stage IV high grade neuroendocrine tumor of the pancreas with metastasis to the liver and lymph nodes whose disease progressed despite treatment with systemic therapy who presented with severe hypoglycemia. Diagnosis and management of his hypoglycemia was difficult. For the diagnosis, patient's serum blood glucose did not always correlate with his capillary blood glucose via finger sticks, which lead to a delay in his diagnosis. Also, his diagnosis was not straight forward as he did not respond adequately to the glucagon following a serum glucose of less than 55 mg/dL (normal 70-110 mg/dL) during a diagnostic fast. Once critical labs were obtained, it took days for the results. In the interim, his hypoglycemia was managed with dextrose infusions at 10%, 20% and as high as 50%, frequent meals, and high dose steroids, yet he still had daily symptomatic hypoglycemia. A diagnosis of insulinoma was made with the following critical lab results: insulin 70.4 uIU/mL (2.6-24.9), C-peptide 12.6 ng/mL (1.1-4.4), proinsulin 407.6 pmol/L (0. 0-10. 0), beta-hydroxybutyrate <0. 050 mmol/L (0. 02-0.27), insulin antibodies <5. 0 uU/mL, negative sulfonylurea screen, insulin-growth factor-1 (IGF-1) 77 ng/mL (90-278), and insulin-growth factor binding protein three (IGF-BP3) 2133 ug/L (2571-5982). Patient was treated with both diazoxide and hepatic artery embolization to reduce tumor burden. His dose of diazoxide was titrated to maintain normoglycemia. He had mild tumor lysis syndrome that did not require dialysis. His hypoglycemia resolved within a few days of treatment and was discharged from the hospital with a continuous glucose monitor (CGM), diazoxide and hydrocortisone. It is our belief that transformation of the liver lesions to insulinoma was the cause of his hypoglycemia.

Conclusion

We recommend that patients with metastases from their neuroendocrine tumor who develop hypoglycemia be evaluated for insulinoma and if found should be treated with diazoxide and if not surgical candidates to consider hepatic artery embolization.

Presentation: No date and time listed

Tertiary Syphilis Masquerading as Oropharyngeal Cancer

Syphilis is re-emerging in the United States. Treponema pallidum, the spirochete bacterium responsible for syphilis, has immunoevasive properties that facilitate pathogenesis and widespread tissue involvement. Host immune status, particularly the presence of HIV/AIDS, can influence the presentation and severity of the disease. Patients co-infected with HIV and syphilis may develop atypical lesions, including those involving the oropharynx. Any immunocompromised patient with tongue lesions and lymphadenopathy is presumed to have a wide differential diagnosis, and tissue sampling with histopathologic analysis is indicated. We present a patient with gumma of the tongue as the initial manifestation of tertiary syphilis.

Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales^1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare⁴ in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet⁵, plasma instabilities^6,7 or orbital motion in an accretion disc^7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. ⁹). BL Lac, the prototype of a subclass of blazars¹⁰, is powered by a 1.7 × 10⁸ M_Sun (ref. ¹¹) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. ¹²)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities⁶ near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

POS0773 AUTOANTIBODIES IN A MULTI-INSTITUTIONAL INDIAN COHORT (INSPIRE) OF SLE PATIENTS: PREVALENCE, CLUSTER ANALYSIS AND PHENOTYPE ASSOCIATION

Background

Systemic Lupus Erythematosus (SLE) is characterized by an array of autoantibodies. Different autoantibodies have been associated with different clinical features like anti-dsDNA antibodies with nephritis and anti-phospholipid antibodies with pregnancy loss. However, the prevalence of autoantibodies has been variable across different ethnic groups. Data on the Indian population is limited.

Objectives

To assess the prevalence of different autoantibodies in a multi-institutional cohort (INSPIRE) of Indian SLE patients and to test their association with various clinical features using cluster analysis

Methods

The patients (n=1053) enrolled in a multi-institutional cohort of Indian patients (Indian SLE inception cohort for Research [INSPIRE]) were included.1 Antibodies were assayed using Immunoline (Euroimmune, Germany) 17 antigen kit. Anti-phospholipid antibodies (IgG and IgM anti-cardiolipin antibodies (ACLs), IgG anti-Beta 2 GpI antibodies) were measured using ELISA (Euroimmune). Lupus anticoagulant was available in a subset of patients.

The prevalence data for autoantibodies were analyzed using an intensity of only ++ and above on Immunoline assay as significant. Univariate analysis by Chi-square test was done to identify associations between individual autoantibodies and their clusters with clinical manifestations.

Results

The clinical features were fever in 702, alopecia in 813, oral ulcers in 628, acute cutaneous lupus (ACLE) in 520, proteinuria in 400, pleural effusion in 181, thrombocytopenia in 250 and autoimmune hemolytic anemia in 137 patients.

The prevalence of various autoantibodies by ELISA was anti-dsDNA antibodies in 70.2% (551/784), IgG Anti- beta-2 GpI in 4.47% (42/938), IgG ACL in 6.14% (61/992) and IgM ACL in 7.1% (54/760). Lupus anticoagulant was present in 13.9% (112/ 805). By Immunoline assay, the prevalence for anti-Ro 52, anti-Ro 60, anti-La and anti-Ribosomal P was 28.49%, 33.14%, 10.07% and 24.03% respectively (Table 1).

Table 1.

Prevalence of different autoantibodies in the INSPIRE lupus cohort

S. No.AutoantibodyPrevalence (%) (n=1053)1.dsDNA28.112.Nucleosomes27.833.Histones24.884.Ro_52_SSA28.495.Ro_60_SSA33.146.SSB-La10.077.Ribosomal P24.038.nRNP36.759.Sm33.1410.Scl-703.2311.PM-Scl0.3812.Jo-10.0913.CENP-B0.3814.PCNA1.3315.AMA-M22.28

Cluster analysis (Figure 1) revealed association (Odds ratio with 95% confidence interval) of Cluster 1 (antibodies against dsDNA, histones and nucleosomes) with arthritis (1.51 [1.18-1.94]), proliferative nephritis (3.05[2.08-4.48]) and pleural effusion (1.49[1.08-2.05]), cluster 2 (antibodies against Sm, nRNP, Ro52, Ro60 and Ribosomal P) with ACLE (1.3[1.02-1.65]) and non-proliferative nephritis (1.64[1.09-2.46]) and cluster 3 (antiphospholipid antibodies) with thrombocytopenia (3.34[1.57-7.11]).

Figure 1.

Cluster analysis of autoantibodies (Cluster 1: dsDNA, histone and nucleosome; cluster 2: Sm, nRNP, Ro52, Ro60 and Ribosomal P; cluster 3: cardiolipin, β2GP1 and La and lupus anticoagulant; cluster 4: Scl-70, Jo-1, PCNA, AMA-M2, PM-SCL and CENP-B)

Conclusion

The prevalence of anti-Sm antibody and Anti-Ribosomal P antibody is higher whereas that of anti-La antibody is lesser in the Indian SLE patients as compared to other cohorts of SLE patients with different ethnicities.2 Cluster analysis reveals co-occurrence of different autoantibodies in our patients and their significant association with various clinical manifestations which suggests a possible pathogenic role of autoantibodies or a common genetic basis for it.

References

[1]Shobha V, Aggarwal A, Rajasekhar L, Jain A, Gupta R, Das B, et al. Indian SLE Inception cohort for Research (INSPIRE): the design of a multi-institutional cohort. Rheumatol Int. 2021 May;41(5):887-894.

[2]Yang J, Xu Z, Sui M, Han J, Sun L, Jia X, et al. Co-Positivity for Anti-dsDNA, -Nucleosome and -Histone Antibodies in Lupus Nephritis Is Indicative of High Serum Levels and Severe Nephropathy. PLoS One. 2015 Oct 14;10(10):e0140441.

Disclosure of Interests

Amita Aggarwal: None declared, Ranjan Gupta Grant/research support from: Dr. Ranjan Gupta has received 2 grants for educating patients and primary care physicians about rheumatoid arthritis managment., Rudrarpan Chatterjee: None declared, Vir Negi: None declared, Bidyut Kumar Das: None declared, Parasar Ghosh: None declared, Debashish Danda: None declared, Vineeta Shobha: None declared

A Review of the MINDSPACE Framework for Nudging Health Promotion During Early Stages of the COVID-19 Pandemic

The coronavirus disease (COVID-19) pandemic has highlighted the link between individual behavior and public health, along with the importance of evidence-based efforts to promote prosocial individual behavior. Insights from behavioral science can inform the design of effective behavior change techniques, or nudges, to influence individual behavior. The MINDSPACE framework organizes 9 behavioral science principles that can be used to guide policy design: Messenger, Incentives, Norms, Defaults, Salience, Priming, Affect, Commitments, and Ego. Using MINDSPACE as an organizing framework, this article provides a review of the literature on nudges to influence prosocial behaviors relevant during a pandemic: handwashing, avoidance of social gatherings, self-isolation and social distancing, and sharing public health messages. Additionally, empirical evidence on the use of nudges during the first several months of the COVID-19 pandemic in 2020 is summarized. Recommendations regarding the use of nudges to achieve public health policy goals during pandemics are provided. Organizational leaders, policymakers, and practitioners can use nudges to promote public health when mandates are not politically feasible or enforceable.

0556 Sex-Specific Relationship Between Anxiety and Autonomic Nervous System Dysfunction in Obstructive Sleep Apnea

Introduction

Cardiovascular co-morbidities in obstructive sleep apnea (OSA) are hard to treat, perhaps due to autonomic nervous system (ANS) dysfunction. In OSA, intermittent hypoxia and poor tissue oxygen perfusion damage endothelial and nervous tissue, potentially underlying the dysfunction. Moreover, OSA is strongly associated with anxiety, which is independently associated with ANS dysfunction. We assessed sex-specific relationships between anxiety and cardiovascular markers of ANS dysfunction in OSA.

Methods

We studied people diagnosed with OSA and healthy controls. We collected 5 minutes of wakeful resting ECG, continuous non-invasive blood pressure, and respiration data. We calculated heart rate (HR), heart rate variability (HRV; sympathetic-vagal balance related to brainstem ANS output), mean arterial blood pressure (MAP), beat-to-beat MAP variability (BPV; related to peripheral autonomic function) and breathing rate (BR). We analyzed these measures with a multivariate regression model of anxiety symptoms (generalized anxiety disorder; GAD-7 scores), sex, and group (OSA vs. control), age/BMI/AHI covariates, and Bonferroni-corrected post-hoc comparisons (p≤0.05).

Results

We analyzed 64 subjects (32 OSA: AHI [mean±SEM] 24±4events/hour, 12 female, age 52±21years, BMI 33±2kg/m2; 32 control: 19 female, age 46±2; BMI 26±1). We observed significant main effects of anxiety, BMI, AHI, sex on HRV, but only group on BPV; post-hoc comparisons revealed high BPV only in OSA females. Secondary analyses included classifying by anxiety symptoms (GAD-7≥5), showing only OSA females with anxiety had higher BPV. Males showed higher HRV. AHI and anxiety were positively correlated with HRV in OSA males. AHI was negatively correlated with BR in OSA females.

Conclusion

We observed higher anxiety associated with higher BPV in OSA, especially in females. Unexpectedly, BR was lower in OSA females; longer breaths may have led to the greater BPV. Higher HRV in males complicated by OSA severity and anxiety could be related to higher sympathetic tone. The slightly older control group may have influenced the findings. Overall, our findings suggest anxiety in OSA is associated with peripheral and centrally-mediated autonomic dysfunction, but in a sex-specific manner.

Support

National Institutes of Health R56-NR-017435 and RO1-HL-135562.

Risk of bleeding in patients undergoing pulmonary procedures on antiplatelet or anticoagulants: A systematic review

As many as 25% of all patients undergoing invasive pulmonary procedures are receiving at least one antiplatelet or anticoagulant agent. For those undergoing elective procedures, the decision-making process is uncomplicated and the procedure may be postponed until the antiplatelet or anticoagulant agent may be safely held. However, many invasive pulmonary procedures are semi-elective or emergent in nature in which case a risk-benefit calculation and discussion occur between the provider and patient or surrogate decision-maker. Therefore, it is critical for providers to have an awareness of the risk of bleeding complications with different pulmonary procedures on various antiplatelet and anticoagulant agents. This systematic review summarizes the bleeding complications associated with different pulmonary procedures in patients on various antiplatelet or anticoagulant agents in the literature and reveals a paucity of high-quality evidence across a wide spectrum of pulmonary procedures and antiplatelet or anticoagulant agents. The results of this review can help inform providers of the bleeding risk in these patients to aid in the shared decision-making process and risk vs benefit discussion.

Towards characterization of photo-excited electron transfer and catalysis in natural and artificial systems using XFELs

The ultra-bright femtosecond X-ray pulses provided by X-ray Free Electron Lasers (XFELs) open capabilities for studying the structure and dynamics of a wide variety of biological and inorganic systems beyond what is possible at synchrotron sources. Although the structure and chemistry at the catalytic sites have been studied intensively in both biological and inorganic systems, a full understanding of the atomic-scale chemistry requires new approaches beyond the steady state X-ray crystallography and X-ray spectroscopy at cryogenic temperatures. Following the dynamic changes in the geometric and electronic structure at ambient conditions, while overcoming X-ray damage to the redox active catalytic center, is key for deriving reaction mechanisms. Such studies become possible by using the intense and ultra-short femtosecond X-ray pulses from an XFEL, where sample is probed before it is damaged. We have developed methodology for simultaneously collecting X-ray diffraction data and X-ray emission spectra, using an energy dispersive spectrometer, at ambient conditions, and used this approach to study the room temperature structure and intermediate states of the photosynthetic water oxidizing metallo-protein, photosystem II. Moreover, we have also used this setup to simultaneously collect the X-ray emission spectra from multiple metals to follow the ultrafast dynamics of light-induced charge transfer between multiple metal sites. A Mn-Ti containing system was studied at an XFEL to demonstrate the efficacy and potential of this method.

Umbrella Sampling and X-ray Crystallographic Analysis Unveil an Arg-Asp Gate Facilitating Inhibitor Binding Inside Phosphopantetheine Adenylyltransferase Allosteric Cleft

Phosphopantetheine adenylyltransferase (PPAT) is a rate-limiting enzyme essential for biosynthesis of coenzyme A (CoA), which in turn is responsible to regulate the secretion of exotoxins via type III secretion system in Pseudomonas aeruginosa, causing severe health concerns ranging from nosocomial infections to respiratory failure. Acetyl coenzyme A (AcCoA) is a newly reported inhibitor of PPAT, believed to regulate the cellular levels of CoA and thereby the pathogenesis. Very little is known so far regarding the mechanistic details of AcCoA binding inside PPAT-binding cleft. Herein, we have used extensive umbrella sampling simulations to decipher mechanistic insight into the inhibitor accommodation inside the binding cavity. We found that R90 and D94 residues act like a gate near the binding cavity to accommodate and stabilize the incoming ligand. Mutational models concerning these residues also show considerable difference in AcCoA-binding thermodynamics. To substantiate our findings, we have solved the first crystal structure of apo-PPAT from P. aeruginosa, which also found to agree with the simulation results. Collectively, these results describe the mechanistic details of accommodation of inhibitor molecule inside PPAT-binding cavity and also offer valuable insight into regulating cellular levels of CoA/AcCoA and thus controlling the pathogenicity.

Nicotine and endometrial decidual growth in pseudopregnant rats

Purpose

The present study aims to investigate the effects of nicotine on the endometrial decidual growth and levels of estrogen and progesterone in pseudopregnant rats.

Methods

Pseudopregnancy (pc) was induced in cyclic Sprague-Dawley rats by sterile mating. Subcutaneous injection of nicotine tartrate (7.5 mg/kg/day) was scheduled from day 1 through day 5, day 5 through day 9 or day 1 through day 9 of pc. In another group of pseudopregnant rats, concomitant treatment of nicotine tartrate concurrently with progesterone (2 mg/day) was scheduled from day 1 through day 9 pc. Control groups received subcutaneous injections of vehicle only. Endometrial decidualization was induced on day 5 pc. On day 10 pc, animals were sacrificed.The degree of decidual growth and circulating levels of estrogen and progesterone were measured.

Results

The decidual growth in all the first three nicotine-treated groups of animals was significantly reduced, particularly in the animals treated with nicotine from day 1 through day 9 pc. Plasma estrogen levels were significantly elevated in animals treated with nicotine from day 1 through day 9 pc. Conversely, levels of plasma progesterone were found to be significantly attenuated in the same group of nicotine-treated animals compared to controls. Exogenous replacement of progesterone, however, caused a higher degree of endometrial decidualization compared to the nicotine-treated group but it was slightly less than when compared to control.

Conclusions

In conclusion, nicotine-induced progesterone deficiency with a corresponding elevation of estrogen may possibly attenuate the degree of endometrial decidualization in pseudopregnant rats.

Effect of lipid composition of cationic SUV liposomes on materno-fetal transfer of warfarin across the perfused human term placenta

INTRODUCTION

Use of drugs that cross the placenta freely are currently avoided during pregnancy. We investigated whether cationic small unilamellar (SUV) liposomes of different lipid compositions could prevent the transfer and uptake of warfarin across human term placenta.

METHODS

Cationic liposomes encapsulated warfarin was prepared by using lecithin (F-SUV) or sterylamine (S-SUV) with cholesterol and stearylamine. The size distribution, encapsulation efficiency, and stability were determined in blood-based media. The transfer kinetics of free and liposomally encapsulated warfarin were studied in a dually perfused isolated lobule of human term placenta with creatinine. Concentrations of warfarin were measured by fluorimetry. Data are expressed as % of initial dose added and given as mean ± sd.

RESULTS

Warfarin crossed the placenta freely (14.9 ± 1.1%). Trans placental transfer of warfarin was significantly reduced by F-SUV (6.4 ± 0.6%; P < 0.001) and S-SUV liposomes (5.0 ± 0.8%; P < 0.001). Placental uptake of F-SUV (6.3 ± 1.7%; P < 0.001) was greater than that of S-SUV liposomes (2.2 ± 0.5%; P < 0.001).

CONCLUSION

Our data suggest that cationic liposomes reduce trans placental transfer of warfarin. If confirmed "in vivo", liposomes might provide an alternative non-invasive method of drug delivery to the mother.

Chromosome structure and pairing preferences in autotetraploid rye (Secale cereale)

The influence of chromosome structure upon pairing behaviour during meiosis was investigated by comparing four autotetraploid genotypes of rye (Secale cereale) containing homologous chromosome sets with different degrees of structural similarity. The series provided a range of genotypes that, at one extreme, contained structurally identical chromosome sets and, at the other extreme, sets that are certainly more heterozygous in the genic sense and probably also more diverse from a purely structural viewpoint. Relative frequencies of pairing configurations at meiotic prophase and metaphase I were compared by electron microscopy of whole-mount surface-spread synaptonemal complex complements and light microscopy of squash preparations. Despite unexpectedly low quadrivalent frequencies over all four genotypes, higher mean bivalent frequencies appeared to be associated with greater homologue diversity. In other words, greater structural divergence between chromosome sets appears to facilitate more efficient discrimination between homologous and identical chromosomes that drives the formation of bivalents. Statistical comparisons were not able to confirm in some cases the significance of the observed pattern of pairing behaviour.

17-AAG mediated targeting of Hsp90 limits tert activity in peritoneal sarcoma related malignant ascites by downregulating cyclin D1 during cell cycle entry

AIM

Peritoneal or retro-peritoneal sarcomatosis related malignant ascites formation is a rare but serious consequence of the locoregional metastatic event. The present work aimed to study the effect of the Hsp90 inhibitor (17-AAG), an ansamycin analog, on cell cycle and DNA replication specific chaperone-clients interaction in the event of peritoneal sarcoma related malignant ascites formation in mouse model at the late stage of malignant growth.

METHODS

We administered 17-AAG, an Hsp90 inhibitor, divided doses (330 μg/kg b.w./day for first five days then next ten days with166 μg/kg b.w./day) through intra-peritoneal route of inbred Swiss albino mice bearing full grown peritoneal malignant ascites of sarcoma-180. Our study was evaluated by peripheral blood hemogram analysis, malignant ascitic cytology, cell viability test, survival time and mitotic indexing. Furthermore, flowcytometric HSP90, TERT, CyclinD1, PCNA and GM-CSF expression analysis has been considered for special objective of the study.

RESULTS

Our experimental efforts reduced the aggressive proliferation of malignant ascites by drastic downregulation of TERT and cyclin D1 on the verge of cell cycle entry along with DNA replication processivity factor PCNA by directly modulating their folding machinery - heat shock protein 90. Consequently, we observed that malignant ascitic cells became error prone during the event of karyokinesis and produced micronucleus containing malignant cells with low viability. Peripheral neutrophilia due to over-expression of GM-CSF by the peritoneal malignant ascites were also controlled by the treatment with 17-AAG and overall, the treatment modality improved the median survival time.

CONCLUSION

Finally we can conclude that 17AAG administration might serve as a prospective pharmacological agent for the management of peritoneal sarcoma related malignant ascites and throws light towards prolonged survival of the patients concerned.

A comparative study of magnetic and dielectric behaviors for La(1-x)Bi(x)Mn(1-y)Fe(y)O3 series (with x = 0.5, 0.7 and y = 0.3, 0.7)

We have carried out an extensive investigation into the effect of doping on both the A- and B-sites for the multiferroic La(0.5)Bi(0.5)Mn(0.5)Fe(0.5)O(3) in relation to its physical properties. The temperature dependent magnetization and dielectric response are determined for different percentages of Bi- and Fe-substitutions. For La(0.5)Bi(0.5)Mn(0.7)Fe(0.3)O(3), there is a prominent ferromagnetic transition T(C) around 110 K, whereas the other La(0.5)Bi(0.5)Mn(0.3)Fe(0.7)O(3) and La(0.3)Bi(0.7)Mn(0.3)Fe(0.7)O(3) phases fail to exhibit any clear transition. On the other hand, for the Fe-rich phases, the coercive field increases to 2450 Oe compared to 1720 Oe (for the Mn-rich phase). All the compositions exhibit coexistence of ferromagnetic and antiferromagnetic phases at low temperatures. The temperature dependent dielectric constant of the investigated samples varies from 32,000 to 500 at room temperature and the data has been analyzed using the universal dielectric response model.

Potassium intake and risk of incident type 2 diabetes mellitus: the Coronary Artery Risk Development in Young Adults (CARDIA) Study

AIMS/HYPOTHESIS

Serum potassium has been found to be a significant predictor of diabetes risk, but the effect of dietary potassium on diabetes risk is not clear. We sought to determine if dietary potassium is associated with risk of incident type 2 diabetes in young adults.

METHODS

We used data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Potassium intake was measured by (1) an average of three 24 h urinary potassium collections at the 5-year study visit, and (2) the CARDIA dietary assessment instrument at baseline. Incident type 2 diabetes cases were ascertained on the basis of use of diabetes medication and laboratory measurements. Analyses were adjusted for relevant confounders including intake of fruit and vegetables and other dietary factors.

RESULTS

Of 1,066 participants with urinary potassium measurements, 99 (9.3%) developed diabetes over 15 years of follow-up. In multivariate models, adults in the lowest urinary potassium quintile were more than twice as likely to develop diabetes as their counterparts in the highest quintile (HR 2.45; 95% CI 1.08, 5.59). Of 4,754 participants with dietary history measurements, 373 (7.8%) developed diabetes over 20 years of follow-up. In multivariate models, African-Americans had a significantly increased risk of diabetes with lower potassium intake, which was not found in whites.

CONCLUSIONS/INTERPRETATION

Low dietary potassium is associated with increased risk of incident diabetes in African-Americans. Randomised clinical trials are needed to determine if potassium supplementation, from either dietary or pharmacological sources, could reduce the risk of diabetes, particularly in higher-risk populations.

HIV encephalopathy in a child in the presence of a high CD4 count: a rare presentation

A two-year-old girl presented with regression of developmental milestones for the last three and a half months. She was diagnosed as HIV-positive, but her CD4 count was found to be normal. Computed tomography (CT) scan of her brain showed bilateral basal ganglia calcification with cortical atrophy. A final diagnosis of HIV encephalopathy was made which had occurred despite a normal CD4 count, which is extremely uncommon.

Awareness of cervical cancer among female students of premier colleges in Kolkata, India

In the absence of any nationwide cervical screening program, cancer of cervix remains a major public health problem for India. We here assessed knowledge levels of female college students about cervical cancer, its risk factors, the human papillomavirus (HPV) etiologic agent and Pap (Papanicolaou) smear testing for screening. We conducted a questionnaire survey of the students (N=630), aged 17 to 24 years, in Kolkata, India. Only 20% correctly identified cervix cancer as the most prevalent female cancer in India, while 43% were aware of the ages of occurrence. Though 41% thought sexual activity to be associated with cervical cancer, its risk factors, like, smoking, having multiple sex partners, cervical infections, early onset of sexual intercourse, multiple parity were recognized by 29%, 3%, 4%, 13% and 15%, respectively. The terms Pap test and HPV had been heard by 11% and 15 % of the students, respectively, and 75% of the students desired to have protective vaccination. Bivariate analysis revealed that educational stream, standard of the college and family size were significantly associated with knowledge levels. Additionally, multivariate regression analysis indicated city students were more knowledgeable than those from outside the city. It is imperative that women gather adequate knowledge on cervical cancer for the success of any program to control the disease. Wide and effective spreading of awareness about the disease among women must form an integral part of public health policy of government.

Hepatitis B Prevalence during pregnancy

In order to determine the efficacy of a new hepatitis B immune globulin (HBIG), a phase 3, vertical transmission (mother to child) clinical interventional trial of hepatitis B virus (HBV) post exposure prophylaxis (PEP) was conducted at selected sites (n=15) throughout India. This required a large screening program for HBsAg positivity at prenatal clinics located in tertiary care hospitals. 36,379 pregnant women consented to be tested for Hepatitis B surface antigen (HBsAg) by Rapid Test and if positive-confirmed by ELISA. The weighted mean prevalence was 0.82% (95% CI, 0.72, 0.91). In conclusion, the prevalence of HBV carrier state during pregnancy in India in this study was low compared to previous reports.

Glucose challenge test screening for prediabetes and undiagnosed diabetes

AIMS/HYPOTHESIS

Diabetes prevention and care are limited by lack of screening. We hypothesised that screening could be done with a strategy similar to that used near-universally for gestational diabetes, i.e. a 50 g oral glucose challenge test (GCT) performed at any time of day, regardless of meal status, with one 1 h sample.

METHODS

At a first visit, participants had random plasma and capillary glucose measured, followed by the GCT with plasma and capillary glucose (GCTplasma and GCTcap, respectively). At a second visit, participants had HbA(1c) measured and a diagnostic 75 g OGTT.

RESULTS

The 1,573 participants had mean age of 48 years, BMI 30.3 kg/m(2) and 58% were women and 58% were black. Diabetes (defined by WHO) was present in 4.6% and prediabetes (defined as impaired glucose tolerance [2 h glucose 7.8-11.1 (140-199 mg/dl) with fasting glucose <or=6.9 (125 mg/dl)] and/or impaired fasting glucose with plasma glucose 6.1-6.9 mmol/l [110-125 mg/dl]) in 18.7%. The GCTplasma provided areas under the receiver-operating-characteristic curves of 0.90, 0.82 and 0.79 for detection of diabetes, diabetes or prediabetes, and prediabetes, respectively, all of which were higher than GCTcap, random and capillary glucose, and HbA(1c) (p < 0.02 for all). The performance of GCTplasma was unaffected by time after meals or time of day, and was better in blacks than whites, but otherwise comparable in men and women, and in groups with differing prevalence of glucose intolerance. GCTplasma screening would cost approximately US$84 to identify one person with previously unrecognised diabetes or prediabetes.

CONCLUSIONS/INTERPRETATION

GCT screening for prediabetes and previously unrecognised diabetes would be accurate, convenient and inexpensive. Widespread use of GCT screening could help improve disease management by permitting early initiation of therapy aimed at preventing or delaying the development of diabetes and its complications.

Observation of zeroth-order band gaps in negative-refraction photonic crystal superlattices at near-infrared frequencies

We present the first observations of zero-n[over ] band gaps in photonic crystal superlattices consisting of alternating stacks of negative-index photonic crystals and positive-index dielectric materials in the near-infrared range. Guided by ab initio three-dimensional numerical simulations, the fabricated nanostructured superlattices demonstrate the presence of zeroth-order gaps in remarkable agreement with theoretical predictions across a range of different superlattice periods and unit cell variations. These volume-averaged zero-index superlattice structures present a new type of photonic band gap, with the potential for complete wave front control for arbitrary phase delay lines and open cavity resonances.

Achieving subdiffraction imaging through bound surface states in negative refraction photonic crystals in the near-infrared range

We report the observation of imaging beyond the diffraction limit due to bound surface states in negative refraction photonic crystals. We achieve an effective negative index figure of merit [-Re(n)/Im(n)] of at least 380, approximately 125x improvement over recent efforts in the near-infrared range, with a 0.4 THz bandwidth. Supported by numerical and theoretical analyses, the observed near-field resolution is 0.47lambda, clearly smaller than the diffraction limit of 0.61lambda. Importantly, we show this subdiffraction imaging is due to the resonant excitation of surface slab modes.

Preparation of nanosize polyaniline and its utilization for microwave absorber

Polyaniline powder in nanosize has been synthesized by chemical oxidative route. XRD, FTIR, and TEM were used to characterize the polyaniline powder. Crytallite size was estimated from XRD profile and also ascertained by TEM in the range of 15 to 20 nm. The composite absorbers have been prepared by mixing different ratios of polyaniline into procured polyurethane (PU) binder. The complex permittivity (epsilon' - jepsilon") and complex permeability (mu' - jmu") were measured in X-band (8.2-12.4 GHz) using Agilent network analyzer (model PNA E8364B) and its software module 85071 (version 'E'). Measured values of these parameters were used to determine the reflection loss at different frequencies and sample thicknesses, based on a model of a single layered plane wave absorber backed by a perfect conductor. An optimized polyaniline/PU ratio of 3:1 has given a minimum reflection loss of -30 dB (99.9% power absorption) at the central frequency 10 GHz and the bandwidth (full width at half minimum) of 4.2 GHz over whole X-band (8.2 to 12.4 GHz) in a sample thickness of 3.0 mm. The prepared composites can be fruitfully utilized for suppression of electromagnetic interference (EMI) and reduction of radar signatures (stealth technology).

Predictors of ovarian reserve in young women with breast cancer

Ovarian reserve can be diminished following treatment for breast cancer. This study evaluated biochemical and biophysical parameters of ovarian reserve in these patients. Biochemical and biophysical tests of ovarian reserve were performed simultaneously in young (age 22–42 years), regularly menstruating women with breast cancer (n=22) and age-matched controls (n=24). All tests were performed before (baseline) and after transient ovarian stimulation in the early follicular phase. Patients were recruited both before and after completion of chemotherapy, with some patients being followed up prospectively. Serum samples were analysed for follicle-stimulating hormone (FSH), luteinising hormone (LH), oestradiol (E₂), inhibins A and B, and antimullerian hormone (AMH). Biophysical (ultrasound) tests included ovarian volume, antral follicle count (AFC), ovarian stromal blood flow and uterine dimensions. Significant differences were revealed (when compared with the controls) for basal FSH (11.32±1.48 vs 6.62±0.42 mIU ml⁻¹, P<0.001), basal AMH (0.95±0.34 vs 7.89±1.62 ng ml⁻¹, P<0.001) and basal inhibin B (19.24±4.56 vs 83.61±13.45 pg ml⁻¹, P<0.001). Following transient ovarian stimulation, there were significant differences in the increment change (Δ) for inhibin B (3.02±2.3 vs 96.82±16.38 pg ml⁻¹, P<0.001) and E₂ (107.8±23.95 vs 283.2±40.34 pg ml⁻¹, P<0.01). AFC was the only biophysical parameter that was significantly different between patients and the controls (7.80±0.85 vs 16.77±1.11, P<0.001). Basal and stimulated biochemical (serum AMH, FSH, inhibin B and E₂) and biophysical (AFC) tests may be potential markers of ovarian reserve in young women with breast cancer.

Leptin and bone turnover in monochorionic twins complicated by twin-twin transfusion syndrome

INTRODUCTION

To test the hypothesis that the bone metabolism of a growth-restricted foetus is regulated by genetic, placental and/or foetal factors through leptin, we investigated the foetal bone turnover in monochorionic pregnancies complicated with or without twin-twin transfusion syndrome (TTTS).

METHODS

Maternal and cord bloods were collected from gestational-age-matched monochorionic twins with (n=15) and without (n=15) TTTS. The samples were assayed for leptin, cross-linked carboxyl terminal telo-peptide (ICTP, a marker of bone resorption) and pro-peptide (PICP, a marker of bone formation) of type I collagen by radioimmunoassay (RIA).

RESULTS

In the growth-restricted donor twin, the plasma concentration of leptin (P < 0.001), PICP (P < 0.001) was lower, while that of ICTP (P < 0.001) was higher than the recipient twin of the TTTS group. In contrast, leptin, PICP and ICTP were comparable in non-TTTS twins. In the recipient twin of TTTS and non-TTTS twins, leptin was positively associated with PICP (r=0.73; n=45, P < 0.001) and negatively with ICTP (r=-0.68; n=45; P < 0.001). No such association was found between leptin and bone marker in the growth-restricted donor twin of the TTTS group.

CONCLUSION

Our data suggest that, in AGA twins, leptin maintains bone metabolism by inhibiting resorption and enhancing bone formation. In contrast, growth-restricted donor twins have high bone turnover and this does not seem to be due to leptin deficiency.

HPV viral load determination during pregnancy as a possible cervical cancer risk

Pregnancy may be a risk factor for cervical human papillomavirus (HPV) infection due to associated increased hormonal level and immunosuppression. Although a majority of such infections are transient, persistent infection may lead to premalignant/malignant cervical lesion. The viral burden is thought to be an indicator for persistence of the infection and malignant transformation. To assess pregnancy as a risk factor for cervical HPV infection, we compared HPV prevalence and viral load among 25 pregnant women to those of 24 non-pregnant and 28 cervical cancer cases. HPV DNA was detected in the cervical cells by PCR using MY09/MY11 primers. HPV positive cases were retested with a low stringency PCR method to ascertain the viral load. HPV prevalences of 68%, 25% and 89% were observed among pregnant women, non-pregnant women and in the cervical cancer cases, respectively. High viral load was frequently (40%) observed in cervical cancer patients. Median viral copy number/cell did not vary much between the non-pregnant and pregnant women. However, pregnant women had a predominantly moderate viral load whereas the low viral load was more frequent in non-pregnant women. High viral load was found to be associated with the presence of HPV 16 in the cervical cancer cases as compared to pregnant/non-pregnant HPV infected women.

Interleukin-10 promoter polymorphisms and atopic asthma in North Indians

BACKGROUND

IL-10 is an anti-inflammatory cytokine primarily produced by monocytes and macrophages and plays a key role in asthma. IL10 gene, present in chromosome 1q31-q32, is regulated primarily by transcription and its expression is found to be lower in asthmatics. Earlier studies in diverse populations have identified several promoter polymorphisms. However, no study has been carried out in a genetically untapped large population from the Indian Subcontinent.

OBJECTIVE

To investigate the association of the IL10 promoter polymorphisms and asthma in the North Indian population.

METHODS

The association study was conducted in a case-control as well as in a family-based design. Polymorphism at -1082 A/G, -819 C/T and -592 C/A nucleotides were genotyped in ethnically matched unrelated patients (N=272), unrelated controls (N=307) and nuclear families (N=164).

RESULTS

A suggestive evidence of association was obtained for -1082 A/G polymorphism at the level of alleles and genotypes with asthma in the case-control study (P=0.03). A three-locus haplotype (ATA) was found to be more in asthmatics than in control individuals (P=0.0085). On the other hand, a novel haplotype ATC was found to be more in controls than in asthmatics (P=0.012). These results were further tested in a family-based study. A deviation of transmission was observed for the -1082 A/G polymorphism (P=0.003). The ATA haplotype showed a preferential transmission in asthmatics (P=0.03), while the GCC and a novel ATC haplotype showed preferential non-transmission in asthmatic individuals (P=0.03 and 0.001, respectively).

CONCLUSIONS

Using both case-control and family studies, we provide suggestive evidence that the ATA haplotype is positively, whereas GCC and a novel ATC haplotypes of IL10 gene are negatively associated with asthma in Indian population. Our results are interesting enough as to intensify further research to elucidate the functional significance of these single-nucleotide polymorphisms and haplotypes in asthma pathogenesis.

A new guide to mandibular resection for oral squamous cell carcinoma based on the Cawood and Howell classification of the mandible

A new guide for mandibular resection in the management of oral squamous cell carcinoma based on the Cawood and Howell classification of the jaws is suggested. This was a retrospective review of case records and pre-operative orthopantomograms (OPG), bone scintigraphy and magnetic resonance imaging (MRI). The classification of the mandible was based on the residual bone height as measured in the molar region of the OPG to be equivalent to the Cawood and Howell classification of the mandible (Class I-II dentate or immediate post-extraction), Class III-IV >20mm well-rounded or knife-edge ridge, and Class V-VI <20mm (flat or depressed ridge form). Of the 77 patients, 58% (22/38) of Class I-II, 43% (9/23) of Class III-IV and 6% (1/16) of Class V-VI were treated with a marginal (rim) resection of the mandible. The predictability of the pre-operative investigations was more accurate in the edentulous mandible (Class III-VI). A simple guide is suggested for mandibular resection taking into account the pre-operative investigations, the estimation of invasion clinically, and the Cawood and Howell classification of ridge resorption.

Visual inspection with acetic acid and cytology in the early detection of cervical neoplasia in Kolkata, India

Visual inspection of the cervix after application of 3-5% acetic acid (VIA) is a potential alternative to cytology for screening in low-resource countries. The present study evaluated the performance of VIA, magnified visual inspection after application of acetic acid (VIAM), and cytology in the detection of high-grade cervical cancer precursor lesions in Kolkata (Calcutta) and suburbs in eastern India. Trained health workers with college education concurrently screened 5881 women aged 30-64 years with VIA, VIAM, and conventional cervical cytology. Detection of well-defined, opaque acetowhite lesions close to the squamocolumnar junction; well-defined, circumorificial acetowhite lesions; or dense acetowhitening of ulceroproliferative growth on the cervix constituted a positive VIA or VIAM. Cytology was considered positive if reported as mild dysplasia or worse lesions. All screened women (N = 5881) were evaluated by colposcopy, and biopsies were directed in those with colposcopic abnormalities (N = 1052, 17.9%). The final diagnosis was based on histology (if biopsies had been taken) or colposcopic findings, which allowed direct estimation of sensitivity, specificity, and predictive values. Moderate or severe dysplasia or carcinoma in situ (CIN 2-3 disease) was considered as true positive disease for the calculation of sensitivity, specificity, and predictive values of screening tests. 18.7%, 17.7% and 8.2% of the women tested positive for VIA, VIAM, and cytology. One hundred twenty two women had a final diagnosis of CIN 2-3 lesions. The sensitivities of VIA and VIAM to detect CIN 2-3 lesions were 55.7% and 60.7%, respectively; the specificities were 82.1% and 83.2%, respectively. The sensitivity and specificity of cytology were 29.5% and 92.3%, respectively. All the tests were associated with negative predictive values above 98%. VIA and VIAM had significantly higher sensitivity than cytology in our study; the specificity of cytology was higher than that of VIA and VIAM.