Deciphering benthic ecosystem functioning and resilience in a major port and marine protected area via the multi-trait approach

The preservation of ecosystem functioning of coastal zones, in face of increasing environmental stressors and species extinctions, relies on the functional redundancy and inherent resilience of its inhabitants. To compare the benthic functioning and resilience of a disturbed area with a relatively less impacted area, a study was conducted in Mumbai Port and Malvan Marine Protected Area (MPA), which exhibited contrasting characteristics. The hypothesis posited that the anthropogenically influenced Mumbai port would exhibit lower functional parameters and resilience compared to Malvan. Overall, the MPA presented higher species richness and functional diversity with a greater presence of sensitive species, while Mumbai was dominated by the presence of opportunistic species, as anticipated. However, our findings demonstrated that despite varied trends in species diversity metrics, in both the coastal areas, the resemblance in benthic functioning was high due to similarity in dominant trait profiles. Surprisingly, Functional Richness was higher at Mumbai, while Functional Evenness, Divergence and Dispersion were comparable at both sites. The resilience, as quantified by Functional Redundancy, was also comparable at both areas attributable to the presence of clusters of species with similar traits and a low occurrence of rare traits. The combination of traits observed in both areas was influenced by the extant environmental conditions, as revealed by RLQ analyses. This study underscores the valuable insights provided by the application of Biological Trait Analysis (BTA) tool in deciphering the relationship between species diversity and ecosystem functioning, as well as the resilience capabilities of ecosystems subjected to varying levels of perturbation. Moreover, the incorporation of functional diversity indices yielded valuable inferences regarding ecosystems resilience, which can aid future ecosystem management strategies.

Prevalence and Determinants of Avian Allergic Manifestation in a Selected Rural Population in Mysuru: A Cross-Sectional Survey

Background

Avian diseases should be known to people who raise birds as pets or for commercial purposes. Exposure to high levels of airborne dust and endotoxins is known to cause allergies. This study, therefore, intends to assess avian allergy and its associated factors among poultry workers and bird fanciers in urban Mysuru.

Methods

A cross-sectional study was done over three months among 60 poultry workers and 60 bird fanciers in a selected rural population of the Mysuru district. The participants were selected by simple random sampling method and their data were obtained by interview method using a pre-tested semi-structured questionnaire. Chi-square test/Fisher's exact test was used to check the associations between the demographic variables' avian allergy.

Results

The survey revealed that 31.67% of poultry workers and 53.33% of bird fanciers had symptoms. The majority of the study participants were illiterate and were not using personal protective equipment (PPE) regularly. The results showed a significant association between education (P = 0.013) and the use of PPE (P = 0.020) with avian allergy. Observing the health hazards, 42.10% had respiratory problems, 42.10% had skin problems, and 26.31% had eye problems. Further, a significant association was also found between education and knowledge about diseases (P = 0.001).

Conclusion

The avian allergy among the bird fanciers was higher when compared to poultry workers. It is necessary to organize routine counseling, awareness, and training programs about diseases and prevention strategies related to their work and living environments and keep them updated.

Applying an interpretive machine learning algorithm to predict in-hospital mortality in elderly asian patients with acute coronary syndrome (ACS)

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Mosti TED1 grant

Background

No study has used interpretative Machine Learning (ML) algorithms to predict in-hospital mortality for the Asian elderly (65+). TIMI predicts mortality for STEMI and NSTEMI using two different scores. It was based on the Western cohort with limited Asian data.

Purpose

Develop a single mortality risk scoring system for STEMI and NSTEMI patients and use interpretative ML to identify and analyse risk factors in elderly Asian patients with ACS.

Methods

The National Cardiovascular Disease Database registry identified 4305 elderly. 70% of the data was used to develop algorithms and 30% for validation. Fifty-four parameters were considered, including demographics, cardiovascular risk, medications, and clinical variables. A sequential backward elimination (SBE) algorithm was used to identify variables associated to elderly mortality. XGBoost classification algorithm and SHapley Additive exPlanation (SHAP) were used to understand mortality impact. The SHAP value of each variable represents its impact on model output (mortality). The main performance metric was area under the curve (AUC). The model was validated using a validation dataset and compared to STEMI and NSTEMI for TIMI.

Results

XGBoost's validation dataset performance using the top 12 predictors from SBE for; STEMI (AUC = 0.822, 95% CI: 0.775-0.868, Accuracy: 0.875, Sensitivity: 0.164, Specificity: 0.966) and NSTEMI (AUC = 0.853, 95% CI: 0.802-0.904, Accuracy: 0.950, Sensitivity: 0.154, Specificity: 0.997). XGBoost's validation dataset performance using the eight emergency predictors selected from the top twelve predictors for; STEMI (AUC = 0.813, 95% CI: 0.766-0.861, Accuracy: 0.868, Sensitivity: 0.194, Specificity 0.954) and NSTEMI (AUC = 0.867, 95% CI: 0.812-0.921, Accuracy: 0.941, Sensitivity: 0.333, Specificity: 0.978). Both models outperformed TIMI score (STEMI AUC = 0.702, NSTEMI AUC = 0.524). The predictors were chosen and ranked in ascending order using the SHAP values (Figure 1). On the y-axis, the variable names are displayed in ascending order of importance and the colour represents the feature's value, ranging from low to high, allowing comprehension of the distribution of SHAP values for each feature. The x-axis displays the SHAP values. Eight out of the twelve predictors were identified to be emergency variables and was ranked according to SHAP values (Figure 2). When compared to TIMI, cardiac catheterization, percutaneous coronary intervention, and pharmacotherapy drugs are chosen as predictors that improve mortality prediction in STEMI and NSTEMI elderly patients. High killip class and age are linked to a poorer ACS patient survival rate, but cardiac catheterization and use of pharmacotherapy drugs improve patient mortality.

Conclusions

A single algorithm can better classify elderly ASIAN patients with ACS than TIMI, which requires two scores. The use of interpretative algorithms aids in the understanding of ACS elderly hospital mortality factors.

Development and validation of a comprehensive needs assessment tool to assess the burden of cancer chemotherapy patients attending a tertiary care hospital

INTRODUCTION

In India in 2020, there were an estimated 1.39 million cancers present in the country. Chemotherapy patients experience several problems such as ADRs (adverse drug reactions), and because of this, many dropouts have been happening. Also, there is a lack of communication between the patient and care providers (doctors).

OBJECTIVES

Development and validation of a comprehensive needs assessment tool to assess the burden of chemotherapy on patients attending tertiary level health care facilities.

MATERIALS AND METHODS

Development and validation of comprehensive needs assessment in cancer chemotherapy involve several steps, including problem statement and literature review regarding the problem, domain generation, development of the preliminary questionnaire, face validation, statistical validation, and final draft of the tool.

RESULTS

A total of 10 experts are involved in face validation. The majority (80%) of the experts agreed with the grammar, clarity, and content of the tool. A few experts (20%) disagreed regarding the construction of the questionnaire, the appropriate level of understanding for the participants, and the content of the tool and suggested changes in the physical and psychological domains. The questionnaire has been re-structured according to the expert's suggestion before going for statistical validation. Internal consistency of the CNAT-CC was optimal, with a satisfactory Cronbach's alpha of 0.7 for the total scale.

DISCUSSION

The current study was focused on the development and validation of needs assessment in cancer chemotherapy patients. The CNAT-CC promises to be a comprehensive needs assessment tool that applies to a comparatively vast majority of patients undergoing cancer chemotherapy.

Comparative efficacy of coronally advanced flap with and without guided tissue regeneration in the management of gingival recession defects: A split-mouth trial

Background

The gingival recession causes tooth sensitivity, poor esthetics, and tooth mobility in severe cases. Scientific documentation revealed effective root coverage (RC) and increased keratinized tissue heights acquired with the coronally advanced flap (CAF) for multiple recession defects.

Objectives

This research evaluates and compares the efficacy of CAF procedures with and without Type I collagen bio-absorbable membrane in guided tissue regeneration (GTR) in the treatment of Miller's Class I and II gingival recession.

Materials and Methods

A total of 30 sites from 15 patients were selected for the study after fulfilling the presurgical phase of treatment. The chosen sites were randomly allocated into Group A CAF and Group B (CAF + Resorbable GTR membrane). The clinical variables such as plaque index, gingival index, recession depth (RD), recession width (RW), width of keratinized gingiva (WKG), clinical attachment level (CAL), and surface area of the defect were recorded at the baseline and 6 months postoperatively.

Results

Both therapies resulted in a notable gain in RC with a mean of 73.13% and 71.60%, respectively, but it was not statistically significant when compared between the groups. Both the RD and RW were significantly reduced from baseline to 6 months postoperatively. Although there was a gain in WKG and CAL in both experimental sites, no significant difference was observed between both the groups.

Conclusion

Although there are several RC procedures, CAF furnishes a foreseeable, straightforward, and appropriate perspective for treating Miller's Class I and II recessions. Integrating this approach with placing a bio-absorbable membrane does not seem to improve the results following surgical treatment of such defects. However, both groups showed the potential advantage of achieving RC.

An android smartphone-based randomized intervention improves the quality of life in patients with type 2 diabetes in Mysore, Karnataka, India

BACKGROUND AND AIMS

Associated with severe complications and morbidity, Diabetes Mellitus is a significant public health burden. The need for regular monitoring and adherence to treatment and lifestyle changes have a high impact on the quality of life of the patients. This study attempts to assess the effect of smartphone-based lifestyle modification intervention in the quality of life of patients with type 2 Diabetes through a randomized filed trial.

METHODS

A randomized field trial was performed among the patients attending the outpatient department of a tertiary care hospital in Mysuru city. A mobile application named DIAGURU, mainly focusing on the lifestyle modification and medication management was used for a period of 6 months from April 2019 to September 2019 by 150 patients in the intervention group while another 150 participants served as controls. The quality of life was assessed using the WHO QOL BREF questionnaire at the beginning of the study and after six months.

RESULTS

The change in the quality of life in a positive direction was significantly higher in the intervention group compared to the non-intervention group after six months. The differences in the change in scores of quality of life of participants recruited in intervention and non-intervention groups were statistically significant in all the four domains after the intervention with a p value < 0.001.

CONCLUSION

The evidence generated in this study suggest that such technological approaches can be used as a public health measure to improve the quality of life of patients with type 2 Diabetes Mellitus.

Geographic information system and foldscope technology in detecting intestinal parasitic infections among school children of South India

BACKGROUND

Effective and efficient use of technological advances will ease public health interventions and also help in reaching a larger population. Geographic Information System (GIS) and Foldscope are two such technologies, which have promising utilities in public health. Identifying intestinal parasitic infections early through feasible technologies will help in their effective management. With this objective, this study was conducted to assess the prevalence of intestinal parasitic infections among school children in southern districts of Karnataka, India.

METHODS

This cross-sectional study was conducted among randomly selected 10 urban, 10 rural, and 5 tribal schools of southern districts of Karnataka. A total of 1052 children studying in these schools were selected. Stool samples were collected and examined under Foldscope for parasitic infestation. The schools where children with worm infestations present were plotted in the GIS map.

FINDINGS

Among 1052 children included in this study, 139 (13.2%) were found to have an intestinal parasitic infestation. Among these children, 24.6% were in the age group of 5-9 years, 12.2% were males, and 14.4% were females. Urban students had higher odds (2.765) of parasitic infections compared to rural students. Mean age, height, and weight were significantly lesser among subjects with a worm infestation.

INTERPRETATION

Utility of Foldscope and GIS was found to be feasible and effective in the detection and mapping of parasitic infestations. The prevalence of parasitic infestation was found to be high among urban school children. Age, weight, height, and urban residence were found to be the major predictors of outcome.

Evaluation of Serum C-reactive Protein Levels in Subjects with Aggressive and Chronic Periodontitis in Comparison with Healthy Controls: A Clinico-biochemical Study

Aim:

Evaluation and comparison of serum C-reactive protein (CRP) levels in subjects with chronic and aggressive periodontitis.

Materials and Methods:

Based on the periodontal status, 45 subjects were selected and divided into three groups. Group I – subjects with clinically healthy periodontium, Group II – generalized aggressive periodontitis (GAP), and Group III – chronic periodontitis (CP). Blood samples were collected from subjects for measurement of CRP. Periodontal parameters include plaque index (PI), gingival index, bleeding index (BI), probing pocket depth (PPD), and clinical attachment loss (CAL) were assessed. CRP levels were assessed by means of a commercially available high sensitivity-CRP enzyme immunoassay kit.

Results:

CRP levels were increased in Group III (6.0671 ± 3.15639 mg/L) and Group II subjects (4.5453 ± 2.88116 mg/L) compared to the Group I (1.0180 ± 0.94069 mg/L). CRP levels showed a positive correlation with all clinical parameters in Group I subjects. BI (r = 0.073), PI (r = 0.120) showed a positive correlation with CRP level in Group II and a positive correlation was also seen for PI (r = 0.492), PPD (r = 0.340), CAL (r = 0.160), and CRP level in Group III subjects.

Conclusion:

The mean CRP levels were found to be greater in CP compared to GAP subjects, but there was no statistically significant difference.

Marine Fungal and Bacterial Isolates for Lipase Production: A Comparative Study

Lipases, belonging to the class of enzymes called hydrolases, can catalyze triglycerides to fatty acids and glycerol. They are produced by microbes of plant and animal origin, and also by marine organisms. As marine microorganisms thrive in extreme conditions, lipases isolated from their origin possess characteristics of extremozymes, retain its activity in extreme conditions and can catalyze few chemical reactions which are impossible otherwise relative to the lipase produced from terrestrial microorganisms. Lipases are useful in many industries like detergent, food, leather, pharmaceutical, diary, etc. Few commercial enzymes have been developed and the use of them in certain industries like dairy, soaps are proved to be beneficial. There are few research papers reporting the production of lipase from marine bacteria and fungi. Lipase production involves two types of fermentation processes-solid-state fermentation (SSF) and submerged fermentation (SmF). Although SmF process is used conventionally, SSF process produces lipase in higher amounts. The production is also influenced by the composition of the medium, physiochemical parameters like temperature, pH, carbon, and nitrogen sources.

Solid-State Fermentation vs Submerged Fermentation for the Production of l-Asparaginase

l-Asparaginase, an enzyme that catalyzes l-asparagine into aspartic acid and ammonia, has relevant applications in the pharmaceutical and food industry. So, this enzyme is used in the treatment of acute lymphoblastic leukemia, a malignant disorder in children. This enzyme is also able to reduce the amount of acrylamide found in carbohydrate-rich fried and baked foods which is carcinogenic to humans. The concentration of acrylamide in food can be reduced by deamination of asparagine using l-Asparaginase. l-Asparaginase is present in plants, animals, and microbes. Various microorganisms such as bacteria, yeast, and fungi are generally used for the production of l-Asparaginase as it is difficult to obtain the same from plants and animals. l-Asparaginase from bacteria causes anaphylaxis and other abnormal sensitive reactions. To overcome this, eukaryotic organisms such as fungi can be used for the production of l-Asparaginase. l-Asparaginase can be produced either by solid-state fermentation (SSF) or by submerged fermentation (SmF). SSF is preferred over SmF as it is cost effective, eco-friendly and it delivers high yield of enzyme. SSF process utilizes agricultural and industrial wastes as solid substrate. The contamination level is substantially reduced in SSF through low moisture content. Current chapter will discuss in detail the chemistry and applications of l-Asparaginase enzyme and various methods available for the production of the enzyme, especially focusing on the advantages and limitations of SSF and SmF processes.

Burgeoning menopausal symptoms: An urgent public health concern

INTRODUCTION

Demographic and epidemiological transitions have increased the life expectancy of people in India. This has resulted in higher burden of morbidities related to aging. The National Health programmes have focused mainly on the health of women in reproductive age groups and neglected their health thereafter. Thus, there is a need to explore the bio-social correlates of menopausal symptoms among women, which can influence their quality of life.

SUBJECTS AND METHODS

This cross-sectional community-based study was conducted in the urban slum of Mysore for 3 months. A total of 100 postmenopausal women in the age group of 40-65 years residing in the field practice area of Urban Health Training Centre were selected by simple random sampling method from the database of households. Details regarding socio-demographic characteristics, postmenopausal symptoms, and factors associated with them were collected in a pretested structured pro forma by interview technique.

RESULTS

Among 100 women included in the present study, mean age at menarche and menopause was 13.45 ± 1.72 and 46.7 ± 5.2 years, respectively. The most common postmenopausal symptom was joint pain (92%) followed by physical and mental exhaustion (84%), depression (76%), irritability (73%), hot flushes, and night sweats (65%). There was a significant positive correlation between age of the women, duration of life after menopause, and postmenopausal symptoms.

CONCLUSION

There is a high burden of postmenopausal symptoms which have shown an increasing trend with advancement of age. This calls for establishment of specific health interventions for postmenopausal women in the health-care settings.

Targeting self-renewal pathways in cancer stem cells: clinical implications for cancer therapy

Extensive cancer research in the past few decades has identified the existence of a rare subpopulation of stem cells in the grove of cancer cells. These cells are known as the cancer stem cells marked by the presence of surface biomarkers, multi-drug resistance pumps and deregulated self-renewal pathways (SRPs). They have a crucial role in provoking cancer cells leading to tumorigenesis and its progressive metastasis. Cancer stem cells (CSCs) are much alike to normal stem cells in their self-renewal mechanisms. However, deregulations in the SRPs are seen in CSCs, making them resistant to conventional chemotherapeutic agents resulting in the tumor recurrence. Current treatment strategies in cancer fail to detect and differentiate the CSCs from their non-tumorigenic progenies owing to absence of specific biomarkers. Now, it has become imperative to understand complex functional biology of CSCs, especially the signaling pathways to design improved treatment strategies to target them. It is hopeful that the SRPs in CSCs offer a promising target to alter their survival strategies and impede their tumorigenic potential. However, there are many perils associated with the direct targeting method by conventional therapeutic agents such as off targets, poor bioavailability and poor cellular distribution. Recent evidences have shown an increased use of small molecule antagonists directly to target these SRPs may lead to severe side-effects. An alternative to solve these issues could be an appropriate nanoformulation. Nanoformulations of these molecules could provide an added advantage for the selective targeting of the pathways especially Hedgehog, Wnt, Notch and B-cell-specific moloney murine leukemia virus integration site 1 in the CSCs while sparing the normal stem cells. Hence, to achieve this goal a complete understanding of the molecular pathways corroborate with the use of holistic nanosystem (nanomaterial inhibition molecule) could possibly be an encouraging direction for future cancer therapy.

World health organization-body mass index for age criteria as a tool for prediction of childhood and adolescent morbidity: a novel approach in southern karnataka, India

BACKGROUND

Health status of children and adolescents is determined to a larger extent by their nutritional status. There are no published studies available on the influence of thinness on childhood morbidity using new World Health Organization-body mass index (WHO-BMI) for age criteria.

METHODS

This cross-sectional study was conducted in primary, high schools, pre-university and degree colleges at southern Karnataka for a period of 1 year.

RESULTS

Majority 6924 (53.6%) were in the age group of 15-19 years with the mean age of 14.2 ± 3.1 years. 6167 (47.7%) were males and 6749 (52.3%) were females. As per WHO growth standards for children between 5 and 19 years, taking BMI for age criteria into account, 9092 (70.4%) subjects were found to be normal, 3660 (28.3%) thin and 164 (1.3%) overweight/obesity. 8224 (63.7%) subjects were suffering from some sort of morbidities. Mean morbidities rank for subjects with thinness was found to be significantly higher compared with normal and overweight/obese subjects. Thinness was found to be the major predictor of morbidity age, sex and residing in rural areas.

CONCLUSIONS

Magnitude of thinness among children and adolescents was 28.3%. BMI for age criteria was found to be a significant predictor of childhood and adolescent morbidity.

Subdural haematoma due to dural metastases from bronchogenic carcinoma in a previously well patient: an unusual cause of non-traumatic recurrent intracranial haematomata

Subdural haematomata (SDH) are usually traumatic in aetiology. Non-traumatic instances of SDH are uncommon, and can rarely be due to metastases involving the dura. Computed tomography or magnetic resonance imaging can be misleading, as the underlying aetiology may be masked by the SDH, or the appearance can simulate meningiomas. A high index of suspicion for SDH is thus required. Under such circumstances, when no overt cause is identified, dural tissue should be sent for histological analysis and blood clot for cytology, even if the appearances are grossly normal at surgery. We present a rare case of a 42-year-old woman who was previously well, but presented with progressive weakness due to acute spontaneous SDH. She required repeated surgical evacuations for SDH and for subsequent recurrent extradural haematomata. After extensive investigations, the cause was identified to be secondary dural metastases from a primary lung carcinoma.

Batch and fed batch production of pectin lyase and pectate lyase by novel strain Debaryomyces nepalensis in bioreactor

The effect of various parameters such as pH, agitation and aeration was studied for maximum production of pectin lyase (PL) and pectate lyase (PGL) by a novel yeast strain Debaryomyces nepalensis in bioreactor. The optimal levels of pH, aeration and agitation rate was found to be 7.0, 300rpm and 1vvm, respectively. Under these conditions, D. nepalensis produced 14,200U/L of PL and 12,000U/L of PGL corresponding to a productivity of 600U/Lh and 500U/Lh of PL and PGL, respectively. Fed-batch production was studied by feeding inducer (lemon peel), carbon source (galactose) individually and in combination at 12h of growth for enhanced production of PL and PGL. Combined feeding of inducer and carbon source at 12h was found to be the best strategy for enhanced production of PL and PGL. Under these conditions, production of PL and PGL increased to 23,300U/L and 22,400U/L, respectively which corresponded to a productivity of 728U/Lh of PL and 700U/Lh of PGL, respectively. The production was increased by 1.6- and 1.8-fold and productivity by 1.2- and 1.4-fold for PL and PGL, respectively when compared to batch culture.

Microbial pectic transeliminases

Pectic transeliminases, also known as pectic lyases or pectinases, are involved in the degradation of pectic substances. They have a wide range of applications in food and textile processing. Although Aspergillus and Penicillium spp. produce pectin lyases, bacteria are the major producers of polygalacturonate lyase. The yields of pectic transeliminases are less than other pectinases. Since new applications for pectic transeliminases are emerging, an improved process for the production of these enzymes is necessary.

Chemical modification of poly(vinyl chloride) resin using poly(ethylene glycol) to improve blood compatibility

Poly(vinyl chloride) (PVC) was aminated by treating the resin with a concentrated aqueous solution of ethylenediamine. The aminated PVC was then reacted with hexamethylene diisocyanate to incorporate the isocyanate group onto the polymer backbone. The isocyanated PVC was further reacted with poly(ethylene glycol) (PEG) of molecular weight 600 Da. The modified polymer was characterized using infrared and X-ray photoelectron spectroscopy (XPS) and thermal analysis. Infrared and XPS spectra showed the incorporation of PEG onto PVC. The thermal stability of the modified polymer was found to be lowered by the incorporation of PEG. Contact angle measurements on the surface of polymer films cast from a tetrahydrofuran solution of the polymer demonstrated that the modified polymer gave rise to a significantly hydrophilic surface compared to unmodified PVC. The solid/water interfacial free energy of the modified surface was 3.9 ergs/cm(2) as opposed to 18.4 ergs/cm(2) for bare PVC surface. Static platelet adhesion studies using platelet-rich plasma showed significantly reduced platelet adhesion on the surface of the modified polymer compared to control PVC. The surface hydrophilicity of the films was remarkably retained even in the presence of up to 30 wt% concentration of the plasticizer di-(2-ethylhexyl phthalate). The study showed that bulk modification of PVC with PEG using appropriate chemistry can give rise to a polymer that possesses the anti-fouling property of PEG and such bulk modifications are less cumbersome compared to surface modifications on the finished product to impart anti-fouling properties to the PVC surface.

Xenon arc photocoagulation for treatment of subluxation of lens

In the treatment of congenital or acquired subluxation of the lens a conservative approach to reposition the pupil in front of the aphakic area by the use of the xenon arc photocoagulator is emphasised. The management of two cases of subluxation is discussed in detail and the results evaluated. The ease of repositioning the pupil by means of iris photocoagulation and the absence of surgical complications are indications for the use of this non-invasive procedure in the treatment of subluxated lenses.

Influence of oestradiol on tissue respiration of the Indian garden lizard, Calotes versicolor

Ovariectomy reduced the respiratory rates of liver and skeletal muscle homogenates of the Indian garden lizard, Calotes versicolor. Administration of oestradiol dipropionate elevated the rate of tissue respiration of ovariectomized animals. This finding lends support to the view that oestradiol, like testosterone, is able to stimulate the oxidative metabolism of this animal.

Thyroid activity and (Hemidactylus flaviviridis Rüppell) in relation to sex hormones

Orchidectomy in Hemidactylus flaviviridis led to significant reduction of thyroidal 131I uptake, thyroidal content of thyroxine, plasma protein-bound iodine and oxygen consumption of isolated liver and skeletal muscle (at 30 °C). Administration of testosterone to orchidectomized lizards restored these parameters to normal levels. Dependence of thyroid function and oxidative metabolism on male hormone may be a general feature in reptiles. This hormone may, therefore, be of greater physiological importance in these animals than in other vertebrates. Since reptiles occupy a crucial phylogenetic position in the animal kingdom these findings are important from the point of view of evolution of the functional aspects of hormones in vertebrates.

The results also show that thyroid function is inhibited by oestrogen(s) in this lizard. This may be an adaptive compensatory measure to control (through effects of the thyroid on metabolic activities) the extra expenditure of energy usually associated with such energy-consuming functions as ovulation and egg-laying.

Metabolic response to male hormone and thyroid activity in the Indian garden lizard, Calotes versicolor

Thyroidectomy and orchidectomy led to significant reduction in the oxidative metabolism of isolated liver and skeletal muscle tissue (at 30 °C) in Calotes versicolor. Thyroxine and male hormone were shown to increase this parameter in intact and orchidectomized lizards respectively. The effects of thyroidectomy and orchidectomy on tissue oxygen uptake were not additive. It is supposed that by its effect on oxidative metabolism male hormone may be of a greater physiological importance for reptiles than for other vertebrates.

The present results show also that changes in environmental temperature can counteract the depressive effect of orchidectomy on the thyroid of this species of lizard.