Self-Attention MHDNet: A Novel Deep Learning Model for the Detection of R-Peaks in the Electrocardiogram Signals Corrupted with Magnetohydrodynamic Effect

Magnetic resonance imaging (MRI) is commonly used in medical diagnosis and minimally invasive image-guided operations. During an MRI scan, the patient's electrocardiogram (ECG) may be required for either gating or patient monitoring. However, the challenging environment of an MRI scanner, with its several types of magnetic fields, creates significant distortions of the collected ECG data due to the Magnetohydrodynamic (MHD) effect. These changes can be seen as irregular heartbeats. These distortions and abnormalities hamper the detection of QRS complexes, and a more in-depth diagnosis based on the ECG. This study aims to reliably detect R-peaks in the ECG waveforms in 3 Tesla (T) and 7T magnetic fields. A novel model, Self-Attention MHDNet, is proposed to detect R peaks from the MHD corrupted ECG signal through 1D-segmentation. The proposed model achieves a recall and precision of 99.83% and 99.68%, respectively, for the ECG data acquired in a 3T setting, while 99.87% and 99.78%, respectively, in a 7T setting. This model can thus be used in accurately gating the trigger pulse for the cardiovascular functional MRI.

Machine Learning-Based Respiration Rate and Blood Oxygen Saturation Estimation Using Photoplethysmogram Signals

The continuous monitoring of respiratory rate (RR) and oxygen saturation (SpO2) is crucial for patients with cardiac, pulmonary, and surgical conditions. RR and SpO2 are used to assess the effectiveness of lung medications and ventilator support. In recent studies, the use of a photoplethysmogram (PPG) has been recommended for evaluating RR and SpO2. This research presents a novel method of estimating RR and SpO2 using machine learning models that incorporate PPG signal features. A number of established methods are used to extract meaningful features from PPG. A feature selection approach was used to reduce the computational complexity and the possibility of overfitting. There were 19 models trained for both RR and SpO2 separately, from which the most appropriate regression model was selected. The Gaussian process regression model outperformed all the other models for both RR and SpO2 estimation. The mean absolute error (MAE) for RR was 0.89, while the root-mean-squared error (RMSE) was 1.41. For SpO2, the model had an RMSE of 0.98 and an MAE of 0.57. The proposed system is a state-of-the-art approach for estimating RR and SpO2 reliably from PPG. If RR and SpO2 can be consistently and effectively derived from the PPG signal, patients can monitor their RR and SpO2 at a cheaper cost and with less hassle.

Lightweight End-to-End Deep Learning Solution for Estimating the Respiration Rate from Photoplethysmogram Signal

Respiratory ailments are a very serious health issue and can be life-threatening, especially for patients with COVID. Respiration rate (RR) is a very important vital health indicator for patients. Any abnormality in this metric indicates a deterioration in health. Hence, continuous monitoring of RR can act as an early indicator. Despite that, RR monitoring equipment is generally provided only to intensive care unit (ICU) patients. Recent studies have established the feasibility of using photoplethysmogram (PPG) signals to estimate RR. This paper proposes a deep-learning-based end-to-end solution for estimating RR directly from the PPG signal. The system was evaluated on two popular public datasets: VORTAL and BIDMC. A lightweight model, ConvMixer, outperformed all of the other deep neural networks. The model provided a root mean squared error (RMSE), mean absolute error (MAE), and correlation coefficient (R) of 1.75 breaths per minute (bpm), 1.27 bpm, and 0.92, respectively, for VORTAL, while these metrics were 1.20 bpm, 0.77 bpm, and 0.92, respectively, for BIDMC. The authors also showed how fine-tuning a small subset could increase the performance of the model in the case of an out-of-distribution dataset. In the fine-tuning experiments, the models produced an average R of 0.81. Hence, this lightweight model can be deployed to mobile devices for real-time monitoring of patients.

A Novel Machine Learning Approach for Severity Classification of Diabetic Foot Complications Using Thermogram Images

Diabetes mellitus (DM) is one of the most prevalent diseases in the world, and is correlated to a high index of mortality. One of its major complications is diabetic foot, leading to plantar ulcers, amputation, and death. Several studies report that a thermogram helps to detect changes in the plantar temperature of the foot, which may lead to a higher risk of ulceration. However, in diabetic patients, the distribution of plantar temperature does not follow a standard pattern, thereby making it difficult to quantify the changes. The abnormal temperature distribution in infrared (IR) foot thermogram images can be used for the early detection of diabetic foot before ulceration to avoid complications. There is no machine learning-based technique reported in the literature to classify these thermograms based on the severity of diabetic foot complications. This paper uses an available labeled diabetic thermogram dataset and uses the k-mean clustering technique to cluster the severity risk of diabetic foot ulcers using an unsupervised approach. Using the plantar foot temperature, the new clustered dataset is verified by expert medical doctors in terms of risk for the development of foot ulcers. The newly labeled dataset is then investigated in terms of robustness to be classified by any machine learning network. Classical machine learning algorithms with feature engineering and a convolutional neural network (CNN) with image-enhancement techniques are investigated to provide the best-performing network in classifying thermograms based on severity. It is found that the popular VGG 19 CNN model shows an accuracy, precision, sensitivity, F1-score, and specificity of 95.08%, 95.08%, 95.09%, 95.08%, and 97.2%, respectively, in the stratification of severity. A stacking classifier is proposed using extracted features of the thermogram, which is created using the trained gradient boost classifier, XGBoost classifier, and random forest classifier. This provides a comparable performance of 94.47%, 94.45%, 94.47%, 94.43%, and 93.25% for accuracy, precision, sensitivity, F1-score, and specificity, respectively.

Suicidal Behaviors among Bangladeshi Nurses: A Cross-sectional Study in a Tertiary Care Hospital

Though, suicide is a preventable public health problem but prediction is almost impossible. Nevertheless, past suicidal behaviors are important risk factors which should be considered to prevent deaths by suicides. We aimed to explore the suicidal behaviors among currently employed nurses working in a referral hospital of Bangladesh. This cross-sectional study was conducted from August to September 2018 among 203 currently working nurses of Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh. Data were collected by face to face interview with pre-tested semi-structured questionnaire and analyzed by Statistical Package for the Social Sciences software version 20.0. Among the 203 respondents; 175 were female and 28 were male, whose mean age was 28.96±4.08 years, ranging from 22-40 year. About 71% were married, 75% had educational attainment of diploma in nursing, 2% had family history of mental illness and suicide, and another one percent had family history of suicidal attempts. Prevalence of life time suicidal ideation was found as 10%, one-year prevalence rate 4%, one month 2% and within last two days it was found as 1.5%. Mean age of onset of suicidal ideation of the respondents was 23.81±4.9 year ranging from 17-35 year. Late adolescence was found as the entry time of the suicidal thoughts among this specific group. About one in ten nurses had suicidal ideation in their life time. Further larger scale and longitudinal studies are warranted to find out more precise information.

Estimating Blood Pressure from the Photoplethysmogram Signal and Demographic Features Using Machine Learning Techniques

Hypertension is a potentially unsafe health ailment, which can be indicated directly from the blood pressure (BP). Hypertension always leads to other health complications. Continuous monitoring of BP is very important; however, cuff-based BP measurements are discrete and uncomfortable to the user. To address this need, a cuff-less, continuous, and noninvasive BP measurement system is proposed using the photoplethysmograph (PPG) signal and demographic features using machine learning (ML) algorithms. PPG signals were acquired from 219 subjects, which undergo preprocessing and feature extraction steps. Time, frequency, and time-frequency domain features were extracted from the PPG and their derivative signals. Feature selection techniques were used to reduce the computational complexity and to decrease the chance of over-fitting the ML algorithms. The features were then used to train and evaluate ML algorithms. The best regression models were selected for systolic BP (SBP) and diastolic BP (DBP) estimation individually. Gaussian process regression (GPR) along with the ReliefF feature selection algorithm outperforms other algorithms in estimating SBP and DBP with a root mean square error (RMSE) of 6.74 and 3.59, respectively. This ML model can be implemented in hardware systems to continuously monitor BP and avoid any critical health conditions due to sudden changes.

Environmental Situation in Some Selected Villages of Bangladesh

Health is multifactorial and influenced by nutritional, biological, chemical and psychological factors. It is quite true that environment has direct impact on those diseases that are the outcome of man's maladjustments to his environment. Often man is responsible for pollution of environment through urbanization, industrialization and other human activities. Improvement of environmental condition is one of the best ways to prevent some of the diseases prevailing in our country. The study was designed to explore the environmental situation of rural area of Bangladesh. The descriptive cross sectional study was conducted in purposively selected six villages of Dewanganj Upazila of Jamalpur district, Bangladesh during the period of January 2018 to February 2018. A total of 227 purposively selected women having at least one under five children were interviewed face to face using a semi-structured questionnaire. Mean±SD age of the respondents was 27.31±6.4 years. About three fourth (167, 73.57%) of the respondents were literate while one fourth (60, 26.43%) of them were illiterate. On the other hand about two third (149, 65.64%) of husbands were literate and remaining (78, 34.36%) were illiterate. The most (215, 94.71%) of the respondents were housewives. Majority (143, 62.99%) of them had children of less than 3 and mean±SD age of children was 2.85±1.17 years. Majority (140, 61.67%) of the respondents belonged to nuclear family while 86 (37.89%) belonged to joint family. Mean±SD family member was 6.42±8.12 persons. The mean monthly family income was BDT 8066.52 with a standard deviation of BDT. 6767.12. Out of 277 respondents, almost half 110(48.46%) of them lived in mixed houses followed by 92(40.53%) and 25(11.01%) lived in Kantcha & Pucca houses respectively. The most (180, 79.30%) of the respondents were used separate kitchen in their houses. About two forth (171, 75.33%) of the respondents did not have any kitchen garden. All 227(100.0%) of the respondents were used tube well as source of drinking water. The most (211, 92.95%) of the respondents got supply water within their compounds. All of the respondents got water supply within 15 minute walking distance. Majority 149(65.64%) of the respondents used sanitary toilets & 40(17.62%) used pit latrines and rest 30(13.22%) of them practiced open air disposal. More than half (118, 51.99%) of the respondents' children were not using toilets for excreta disposal. Efforts are needed to increase environmental health related knowledge and awareness to maintain environment sanitation. People should use sanitary latrines and avoid practice of open air disposal of children's feces to prevent excreta borne diseases. Further wider scale details study is needed to formulate policy in regards to improve the environmental sanitation of Bangladesh.

Heart failure following cancer treatment: characteristics, survival and mortality of a linked health data analysis

BACKGROUND

Cardiotoxicity resulting in heart failure is a devastating complication of cancer therapy. A patient may survive cancer only to develop heart failure (HF), which has a higher mortality rate than some cancers.

AIM

This study aimed to describe the characteristics and outcomes of HF in patients with blood or breast cancer after chemotherapy treatment.

METHODS

Queensland Cancer Registry, Death Registry and Hospital Administration records were linked (1996-2009). Patients were categorised as those with an index HF admission (that occurred after cancer diagnosis) and those without an index HF admission (non-HF).

RESULTS

A total of 15 987 patients was included, and 1062 (6.6%) had an index HF admission. Median age of HF patients was 67 years (interquartile range 58-75) versus 54 years (interquartile range 44-64) for non-HF patients. More men than women developed HF (48.6% vs 29.5%), and a greater proportion in the HF group had haematological cancer (83.1%) compared with breast cancer (16.9%). After covariate adjustment, HF patients had increased mortality risk compared with non-HF patients (hazard ratios 1.67 (95% confidence interval, 1.54-1.81)), and 47% of the index HF admission occurred within 1 year from cancer diagnosis and 70% within 3 years.

CONCLUSION

Cancer treatment may place patients at a greater risk of developing HF. The onset of HF occurred soon after chemotherapy, and those who developed HF had a greater mortality risk.

Prevalence of Psychiatric Disorders among Female Juvenile Offenders

Inmates of Juvenile Developmental Centers are the special group of youth population who are in conflict with law. They are vulnerable to psychiatric illness. The objective of this study was to see the prevalence and type of psychiatric disorders in institutionalized female juvenile offenders and non-offenders of same age, sex and socioeconomic group in the community. The association of mental disorders was examined in 43 female inmates of Juvenile Development Centers and 43 randomly selected comparison subjects in community. One stage-structured assessment of psychopathology was carried out by using a structured and valid Bangla version of the Development and Well-Being Assessment (DAWBA). Development and Well-Being Assessment generated psychiatric diagnosis was assigned based on ICD-10 diagnostic criteria for research. The result revealed that, of those who were in conflict with law, 93% had mental disorder, whereas 14% of non-offenders had psychiatric disorder. Among the offenders with psychiatric disorders, most of them (32.6%) suffered from Major Depressive Disorder (MDD), followed by combined MDD & Post Traumatic Stress Disorder (PTSD). On the other hand, among the non-offenders with psychiatric disorder 9.3% suffered from MDD. It can be concluded that considerable psychiatric disorders are prevalent among the female juvenile offenders with comparison to non-offenders. Broad-based replication study could confirm these findings.

A Patient with Grave's Disease and Tuberculous Lymphadenitis

Immune reactivity between Mycobacteria and human antigens can play an important role in the pathogenesis of autoimmune disease. We report a case of Graves's disease and tuberculous lymphadenitis to explain the mechanism of correlation between immune-mediated diseases and tuberculosis and to raise awareness of the importance of screening for TB in this context, especially in endemic country. Screening for latent TB at immune mediated disease diagnosis and regular timely screening thereafter may be beneficial.

Plasmon-controlled fluorescence towards high-sensitivity optical sensing

Fluorescence spectroscopy is widely used in chemical and biological research. Until recently most of the fluorescence experiments have been performed in the far-field regime. By far-field we imply at least several wavelengths from the fluorescent probe molecule. In recent years there has been growing interest in the interactions of fluorophores with metallic surfaces or particles. Near-field interactions are those occurring within a wavelength distance of an excited fluorophore. The spectral properties of fluorophores can dramatically be altered by near-field interactions with the electron clouds present in metals. These interactions modify the emission in ways not seen in classical fluorescence experiments. Fluorophores in the excited state can create plasmons that radiate into the far-field and fluorophores in the ground state can interact with and be excited by surface plasmons. These reciprocal interactions suggest that the novel optical absorption and scattering properties of metallic nanostructures can be used to control the decay rates, location, and direction of fluorophore emission. We refer to these phenomena as plasmon-controlled fluorescence (PCF). An overview of the recent work on metal-fluorophore interactions is presented. Recent research combining plasmonics and fluorescence suggest that PCF could lead to new classes of experimental procedures, novel probes, bioassays, and devices.

Chemokine-like factor expression in the idiopathic inflammatory myopathies

OBJECTIVES

We evaluated the expression of chemokine-like factor (CKLF) in biopsied muscle fibers in inflammatory myopathies, non-inflammatory myopathies and neurologically diseased controls.

MATERIALS AND METHODS

We studied the expression of CKLF in 15 polymyositis (PM), five dermatomyositis (DM), 15 non-inflammatory myopathies and nine neurologically diseased patients by immunohistochemistry.

RESULTS

Chemokine-like factor was mostly expressed in small diameter muscle fibers surrounded by infiltrated lymphocytes of inflammatory myopathies patients. Parts of them were also positive for the staining of the developmental form of myosin heavy chain, a maker of regenerating muscle fibers. Thrombin immunoreactivity was observed in endomysium in PM and perimysium in DM. In vitro differentiation study showed a constitutive expression of CKLF in myoblasts that was abolished in myotubes during differentiation process and was induced again by thrombin. Thrombin regulates CKLF expression through protease-activated receptor-1 in myotubes. Treatment of a protein kinase C inhibitor partially blocked CKLF expression in myoblasts, while it remarkably inhibited that in myotubes.

CONCLUSION

Chemokine-like factor expression is differentially regulated in myoblasts and myotubes. Thrombin could be a strong regulator for its expression. As CKLF is immunohistochemically positive in regenerating muscle fibers, we postulate here that CKLF is a useful marker for regenerating muscle fibers in inflammatory myopathies.

Neutron capture cross-section measurement for the 186W(n,gamma)187W reaction at 0.0536eV energy

The thermal neutron-induced activation cross section for the (186)W(n,gamma)(187)W reaction was measured at 0.0536eV neutron energy using TRIGA Mark-II research reactor, Atomic Energy Research Establishment, Savar, Dhaka, Bangladesh. The (197)Au(n,gamma)(198)Au monitor reaction induced in a high-purity gold foil was used to determine the effective neutron beam intensity. The activities induced in sample and monitor foils were measured nondestructively by a high-resolution HPGe gamma-ray detector. The present experimental cross-section value is the first one at 0.0536eV. The obtained new cross section that amounts to 26.6+/-1.6b is 2% higher than the recently reported data in ENDF/B-VII and 5% lower than that of JENDL-3.3.

Ciliary staphyloma: very rare sequelae of conjunctival rhinosporiodosis

The main ocular manifestation of rhinosporiosis is lid or conjunctival infection. Conjunctival rhinosporiodosis is very rately causing sclera necrosis. A patient named Shumi (8 years), D/O.- Rukan Uddin of Rupchandrapur, Atpara, Netrokona admitted on 09/03/2003 in the department of Ophtalmology, Mymensingh Medical College Hospital with complains of mass in right eye looks externally like a growth in upper lid and mild dimness of vision of right eye. On examination, it was found that she got VAR : 6/24 and having a shaphyloma near 12-00 O'clock position with a mass adjacent to it which was identified as rhinosporiodosis after excisional biopsy. No history of ocular trauma or any other ocular disease was found.

Antibacterial agents in infections of the central nervous system

Experimental animal models have provided information applicable to antimicrobial therapy of infections of the central nervous system. The efficacy of an antimicrobial agent in the therapy of bacterial meningitis depends on its ability to penetrate the blood-brain barrier, its activity in purulent cerebrospinal fluid, and a demonstration of rapid bactericidal activity against the offending pathogen. The recent emergence of resistant pathogens is challenging the therapy for bacterial meningitis. Various strategies for treating resistant pathogens have been evaluated in experimental animal models. Encouraging results have led to clinical trials to evaluate the efficacy of newer agents, alone or in combination with standard regimens.

Effect of tetracyclines which have metalloproteinase inhibitory capacity on basal and heparin-stimulated bone resorption by chick osteoclasts

Several tetracyclines (TETs) are potent inhibitors of collagenase (CGase) and can inhibit connective tissue degradation in a variety of inflammatory and degenerative disorders. The role of CGase in bone resorption by osteoclasts (OC) remains unclear. Disaggregated OCs from chick embryos were cultured for 24 h on devitalized bovine cortical bone +/- heparin in the presence of various TETs. Doxycycline (Dox) inhibited pit formation in a dose-dependent manner. CMT, a TET derivative which inhibits matrix metalloproteinases (MMPs) but is not antimicrobial, also inhibited chick OC bone resorption. Heparin markedly stimulated bone resorption at 5 micrograms/ml, which was reversed by Dox, 5 micrograms/ml. TETs can reversibly inhibit both basal and heparin-stimulated bone resorption by chick OCs. These findings suggest that MMPs may play a role in osteoclastic bone resorption, and that safe and effective inhibitors of MMPs, including certain TETs, might have a potential therapeutic role.

Effects of heparin on osteoclast activity

The effect of heparin on osteoclastic bone resorption was studied in vitro using the disaggregated osteoclast resorption assay. Bone resorption was assessed by counting the resorption lacunae on bone slices by light microscopy. Low concentrations of heparin (5 micrograms/ml) increased bone resorption by isolated chick and rat osteoclasts. Among other glycosaminoglycans tested at 5 micrograms/ml, only dextran sulfate showed a small but significant stimulation of resorption. Chondroitin sulfates A, B, and C were without effect at 25 and 100 micrograms/ml, whereas resorption was increased by 100 micrograms/ml of heparan sulfate. With chick osteoclasts, which could be maintained in serum-free conditions, a stimulatory effect of heparin was found both in the presence of 5% fetal calf serum and in serum-free media containing insulin, transferrin, and selenium. The magnitude of the heparin-induced increase in resorption was similar in the presence or absence of serum. The stimulation of resorption was associated with an increase in the number of osteoclasts on bone slices. Pretreatment of the bone slices with heparin also enhanced resorption. In time course experiments, 5 micrograms/ml of heparin caused a doubling of chick osteoclast activity index (number of resorption pits per number of osteoclasts) at 12 and 24 h. In 24 h cultures, treatment with 10 micrograms/ml of the arginine-rich basic protein, protamine, 1 microgram/ml of the immunosuppressant, cyclosporine A, or 5 micrograms/ml of the cysteine-proteinase inhibitor, leupeptin, negated the heparin effect on bone resorption. Leupeptin also inhibited basal resorption.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of cyclosporine A on chick osteoclasts in vitro

We have studied the effects of cyclosporine A (CsA) on basal and bovine parathyroid hormone (1-34) (bPTH)-stimulated bone resorption by osteoclasts in 24-hour cultures of chick long bone cells. At a high concentration (10 micrograms/ml), CsA had a cytotoxic effect on both osteoclasts and mononuclear cells in the culture. At 1 microgram/ml, CsA inhibited basal and bPTH-stimulated bone resorption but was not cytotoxic over 24 hours. We also studied the binding of bPTH to the osteoblastic cell line, Saos-2, and chick long bone cells in suspension culture. CsA inhibited bPTH binding in Saos-2 in a dose-dependent manner; inhibition of binding was also observed in chick bone cells. The effects of CsA on osteoclast viability and resorptive function may be due to a direct effect on the osteoclasts and/or to an interaction with the nonosteoclastic cell population in the culture.

Epidermal growth factor counteracts the glycogenic effect of insulin in parenchymal hepatocyte cultures

Rat parenchymal hepatocytes in monolayer culture were used to study the metabolic effects of epidermal growth factor (EGF) and insulin on ketogenesis, gluconeogenesis and glycogen metabolism. EGF, unlike insulin, did not inhibit ketogenesis from palmitate or gluconeogenesis from pyruvate in hepatocyte cultures. It also had no effect on these pathways in the presence of insulin. In contrast, EGF potently counteracted the stimulation of [14C]pyruvate incorporation into glycogen by insulin, and also glycogen deposition from both gluconeogenic precursors and glucose. The EGF concentration causing half-maximal effect was about 0.1 nM. The anti-glycogenic effect of EGF was observed after both long-term (24 h) and short-term (1 h) exposure to EGF, and was more marked in the presence of insulin than in its absence. EGF did not displace bound insulin, suggesting that it neither competes for the insulin receptor nor affects the affinity of the receptor for insulin. EGF did not alter cellular cyclic AMP; and inhibition of cyclic AMP phosphodiesterase activity did not prevent the anti-glycogenic effect of EGF. In liver-derived dividing epithelial cells, Hep-G2 cells and fibroblasts, which have no capacity for gluconeogenesis, EGF did not counteract the stimulatory effect of insulin on [14C]glucose incorporation into glycogen, and in the epithelial cells EGF increased [14C]glucose incorporation into glycogen. The counter-effect of EGF on the glycogenic action of insulin in parenchymal hepatocytes may be due to a direct effect on glycogen metabolism or to an interaction with the post-receptor events in insulin action.

Regulation of ketogenesis, gluconeogenesis and the mitochondrial redox state by dexamethasone in hepatocyte monolayer cultures

The effects of the glucocorticoid dexamethasone on fatty acid and pyruvate metabolism were studied in rat hepatocyte cultures. Parenchymal hepatocytes were cultured for 24 h with nanomolar concentrations of dexamethasone in either the absence or the presence of insulin (10 nM) or dibutyryl cyclic AMP (1 microM BcAMP). Dexamethasone (1-100 nM) increased the rate of formation of ketone bodies from 0.5 mM-palmitate in both the absence and the presence of BcAMP, but inhibited ketogenesis in the presence of insulin. Dexamethasone increased the proportion of the palmitate metabolized that was partitioned towards oxidation to ketone bodies, and decreased the cellular [glycerol 3-phosphate]. The latter suggests that the increased partitioning of palmitate to ketone bodies may be associated with decreased esterification to glycerolipid. The Vmax. of carnitine palmitoyltransferase (CPT) and the affinity of CPT for palmitoyl-CoA were not affected by dexamethasone, indicating that the increased ketogenesis was not due to an increase in enzymic capacity for long-chain acylcarnitine formation. Dexamethasone and BcAMP, separately and in combination, increased gluconeogenesis. In the presence of insulin, however, dexamethasone inhibited gluconeogenesis. Changes in gluconeogenesis thus paralleled changes in ketogenesis. Dexamethasone decreased the [3-hydroxybutyrate]/[acetoacetate] ratio, despite increasing the rate of ketogenesis and presumably the mitochondrial production of reducing equivalents. The more oxidized mitochondrial NADH/NAD+ redox couple with dexamethasone is probably due either to an increased rate of electron transport or to increased transfer of mitochondrial reducing equivalents to the cytoplasm.

Regulation of ketogenesis, gluconeogenesis, and glycogen synthesis by insulin and proinsulin in rat hepatocyte monolayer cultures

The metabolic actions of porcine insulin and biosynthetic human proinsulin on fatty acid and glucose metabolism were studied in rat hepatocytes cultured in monolayer for 24 h. Our aim was to establish whether proinsulin action in the liver is similar to insulin action and whether the relative potencies of the two hormones are the same for different metabolic processes. Proinsulin and insulin exerted a similar maximal inhibitory effect on ketone body formation from palmitate and on gluconeogenesis from pyruvate. The half-maximal effective concentration of proinsulin was 11-13 times that of insulin. The antiketogenic effects of insulin and proinsulin were associated with an increased glycerol 3-phosphate content and a decreased affinity of carnitine palmitoyltransferase for its substrate palmitoyl-CoA. When the basal rate of ketogenesis was increased with isobutyl methylxanthine, the half-maximal effective concentrations of both proinsulin and insulin were decreased, but the relative potency of the two hormones was unchanged. Proinsulin and insulin exerted similar maximal stimulatory effects on glycogen synthesis and on the activities of pyruvate kinase, glucose 6-phosphate dehydrogenase, phosphogluconate dehydrogenase, and malic enzyme. The half-maximal effective concentration of proinsulin was 10-30 times that of insulin. These findings are consistent with receptor binding studies on liver membranes that suggest that proinsulin interacts with insulin-specific and not proinsulin-specific receptors. Our findings also suggest that proinsulin action does not differ from insulin action at a postreceptor site.

Cancer morbidity

In the present study, 1736 cases of cancer has been analysed by major sites, sub-sites and mortality trend. The most common cancerous lesion in the male was in the lungs and in the female in the uterine cervix. The second common lesion in male and female were larynx and breast respectively. In children, retinoblastoma was the commonest type of cancer.