Progression of blood-borne viruses through bloodstream: A comparative mathematical study.

BACKGROUND AND OBJECTIVES: Blood-borne pathogens are contagious microorganisms that can cause life-threatening illnesses, and are found in human blood. It is crucial to examine how these viruses spread through blood flow in the blood vessel. Keeping that in view, this study aims to determine how blood viscosity, and diameter of the viruses can affect the virus transmission through the blood flow in the blood vessel. A comparative study of bloodborne viruses (BBVs) such as HIV, Hepatitis B, and C, has been addressed in the present model. A couple stress fluid model is used to represent blood as a carrying medium for virus transmission. The Basset-Boussinesq-Oseen equation is taken into account for the simulation of virus transmission. METHODS: An analytical approach to derive the exact solutions under the assumption of long wavelength and low Reynolds number approximations is employed. For the computation of the results, a segment (wavelength) of blood vessels about 120 mm with wave velocities in the range of 49 - 190 mm/sec are considered, where the diameter of BBVs ranges from 40-120 nm. The viscosity of the blood varies from 3.5-5.5 × 10-3Ns/m2 which affect the virion motion having a density range 1.03 - 1. 25 g/m3. RESULTS: It shows that the Hepatitis B virus is more harmful than other blood-borne viruses considered in the analysis. Patients with high blood pressure are highly susceptible for transmission of BBVs. CONCLUSIONS: The present fluid dynamics approach for virus spread through blood flow can be helpful in understanding the dynamics of virus propagation inside the human circulatory system.

Propagation of H1N1 virus through saliva movement in oesophagus: a mathematical model.

H1N1 (Swine flu) is caused by the influenza A virus which belongs to the Orthomyxoviridae family. Influenza A is very harmful to the elderly, and people with chronic respiratory disease and cardiovascular disease. Therefore, it is essential to analyse the behaviour of virus transmission through the saliva movement in oesophagus. A mathematical paradigm is developed to study the saliva movement under the applications of transverse magnetic field. Jeffrey fluid model is considered for saliva to show the viscoelastic nature. The flow nature is considered creeping and assumptions of long wavelength and low Reynolds number are adopted for analytical solutions. The Basset-Boussinesq-Oseen equation is employed to understand the propagation of H1N1 virus through saliva under the effect of applicable forces such as gravity, virtual mass, basset force, and drag forces. The suitable data for saliva, oesophagus and H1N1 virus are taken from the existing literature for simulation of the results using MATLAB software. From the graphical results, it is observed that the susceptibility to viral infections is less because the magnetic field reduces the motion of the virus particle. Further, the chances of infections in males are more as compared to females and children due to variation in viscosity of saliva. Such findings provide an understanding of the mechanics of the virus floating through the saliva (viscoelastic fluids) in the oesophagus.

Thyroid function in postpartum psychosis: An exploratory study.

The study aimed to compare thyroid function between psychosis with postpartum onset (PPO), psychosis without postpartum onset (PWPO), and normal postpartum females (HC). Twenty women were recruited in each of the three groups. The PPO group had significantly greater psychopathology and shorter episodes compared to the PWPO group. The PPO group was found to have significantly greater right lobe volume than the other groups. The PPO group also had significantly higher FT4 levels than the HC group. We conclude that isolated increase in FT4 and thyroid lobe volumetric changes could be more specifically associated with psychosis of post-partum onset.

Detection of Depression and Scaling of Severity Using Six Channel EEG Data.

Depression is a psychiatric problem which affects the growth of a person, like how a person thinks, feels and behaves. The major reason behind wrong diagnosis of depression is absence of any laboratory test for detection as well as severity scaling of depression. Any degradation in the working of the brain can be identified through change in the electroencephalogram (EEG) signal. Thus detection as well as severity scaling of depression is done in this study using EEG signal. In this study, features are extracted from the temporal region of the brain using six (FT7, FT8, T7, T8, TP7, TP8) channels. The linear features used are delta, theta, alpha, beta, gamma1 and gamma2 band power and their corresponding asymmetry as well as paired asymmetry. The non-linear features used are Sample Entropy (SampEn) and Detrended Fluctuation Analysis (DFA). The classifiers used are: Bagging along with three different kernel functions (Polynomial, Gaussian and Sigmoidal) of Support Vector Machine (SVM). Feature selection technique used is ReliefF. Highest classification accuracy of 96.02% and 79.19% was achieved for detection and severity scaling of depression using SVM (Gaussian Kernel Function) and ReliefF as feature selection. From the analysis, it was found that depression affects the temporal region of the brain (temporo-parietal region).It was also found that depression affects the higher frequency band features more and it affects each hemisphere differently. It can also be analysed that out of all the kernel of SVM, Gaussian kernel is more efficient to other kernels. Of all the features, combination of all paired asymmetry and asymmetry showed high classification accuracy (accuracy of 90.26% for detection of depression and accuracy of 75.31% for severity scaling).

The National Mental Health Survey of India (2016): Prevalence, socio-demographic correlates and treatment gap of mental morbidity.

BACKGROUND: Recognizing the need for good quality, scientific and reliable information for strengthening mental health policies and programmes, the National Mental Health Survey (NMHS) of India was implemented by National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, in the year 2015-2016. AIM: To estimate the prevalence, socio-demographic correlates and treatment gap of mental morbidity in a representative population of India. METHODS: NMHS was conducted across 12 Indian states where trained field investigators completed 34,802 interviews using tablet-assisted personal interviews. Eligible study subjects (18+ years) in households were selected by a multi-stage, stratified, random cluster sampling technique. Mental morbidity was assessed using MINI 6. Three-tier data monitoring system was adopted for quality assurance. Weighted and specific prevalence estimates were derived (current and lifetime) for different mental disorders. Mental morbidity was defined as those disorders as per the International Statistical Classification of Diseases, Tenth Revision Diagnostic Criteria for Research (ICD-10 DCR). Multivariate logistic regression was conducted to examine risk for mental morbidity by different socio-demographic factors. Survey was approved by central and state-level institutional ethical committees. RESULTS: The weighted lifetime prevalence of 'any mental morbidity' was estimated at 13.67% (95% confidence interval (CI) = 13.61, 13.73) and current prevalence was 10.56% (95% CI = 10.51, 10.61). Mental and behavioural problems due to psychoactive substance use (F10-F19; 22.44%), mood disorders (F30-F39; 5.61%) and neurotic and stress-related disorders (F40-F48; 3.70%) were the most commonly prevalent mental morbidity in India. The overall prevalence was estimated to be higher among males, middle-aged individuals, in urban-metros, among less educated and in households with lower income. Treatment gap for overall mental morbidity was 84.5%. CONCLUSION: NMHS is the largest reported survey of mental morbidity in India. Survey estimated that nearly 150 million individuals suffer from one or the other mental morbidity in India. This information is to be used for planning, delivery and evaluating mental health programming in the country.

Conceptual issues in mood disorder: An update.

The concept of mood disorders dates back to eternity. This long history of the emotions and their disorders has a fascinating journey. As with any history concerned with disease concepts, the conceptual history of mood disorders must be scrutinized through close attention to nosological texts in tracing how categories were created how they evolved over the time. This article covers the evolution of the concept of mood disorders and its journey from the Hippocratic era to the Kraepelin's dichotomization between dementia praecox (schizophrenia) and manic-depressive insanity (bipolar and unipolar disorders) and its culmination into the contemporary classifications of mood disorders. It also addresses the problem of boundaries between the different mood disorders in terms of their conceptualization and classification. The shortcomings of the classificatory systems and the current progress in the nosology have also been discussed.

A Mixed-Methods Approach to Evaluate the Needs, Support, and Services for Common Mental Disorders: A Protocol Examining Two Community Extension Clinics.

BACKGROUND: The social, economic, and physical environments are widely recognized as important determinants of health and affect the outcome of service delivery. The differences in the patient outcomes can be inferred upon by looking into the process and content of service delivery. METHODS: This study is a mixed-methods, prospective cohort study to be conducted at two community extension clinics run by the Central Institute of Psychiatry, Ranchi, Jharkhand. Service users diagnosed with a common mental disorder (CMDs) will be recruited during the study period of three years. The main objective is to ascertain the unmet needs of patients with CMDs. The secondary goals involve measuring the clinical outcome through the lens of process-oriented recovery, service satisfaction, and accessibility, and analyzing the barriers to access healthcare services along with the impact on the carers. Focus group discussions with participants will help understand the reasons behind their unmet needs and factors essential in service delivery. DISCUSSION: Healthcare, as well as social care, aims to deliver services according to need. In a country with 15 million people with CMDs, evaluation of needs could create a platform for the rational distribution of services.

Absconding During Inpatient Care from a Tertiary Psychiatric Hospital: A Comparative Study.

BACKGROUND: Absconding from psychiatric hospitals is of great concern for patients and caregivers. Absconding affects not only the treatment and safety of these patients but also patient's caregivers and the community. Further investigation is needed to examine the pattern of this event and the characteristics of patients who abscond. Hence, our study was aimed to examine the sociodemographic and clinical profiles of inpatients who absconded from a psychiatric hospital in five years and to compare them with matched controls. METHODS: A retrospective chart review of inpatients who absconded and matched control inpatients during the specified period of five years from January 2014 to December 2018 was done at a psychiatric hospital. Each control was matched with a corresponding absconding case on the following order: (a) admission ward, (b) admission period, (c) diagnosis, and (d) age. Results: Among 20,052 adult admissions during the specified period, 38 patients absconded, with a rate of 1.8 per 1,000 admissions. Most of them were male, from a younger age group, diagnosed with schizophrenia or mood disorder, and having comorbid substance use disorder, irritable affect, impaired judgment, and absent insight. Most of the events occurred within the first two weeks of admission. About 11% of them had a history of prior absconding from the hospital. CONCLUSION: Knowledge about the associated sociodemographic and clinical profile would help clinicians and mental health care professionals to prevent absconding. Further risk assessment using a patient's profile would help to reduce absconding events from psychiatric hospitals in the future.

A population-based analysis of suicidality and its correlates: findings from the National Mental Health Survey of India, 2015-16.

BACKGROUND: India accounts for 18% of the global population and 26·6% of global suicide deaths. However, robust population-based, nationally representative data on suicidality are not readily available to plan and implement suicide prevention programmes in India. We aimed to investigate the prevalence and sociodemographic differentials of suicidality using data from the National Mental Health Survey (NMHS) of India, 2015-16. METHODS: Trained field data collectors from the NMHS obtained information on suicidality (during the past month) from a community sample of adults aged 18 years and older using the suicidality module of the Mini-International Neuropsychiatric Interview (version 6.0). Suicidality was categorised as low, moderate, high, and overall (representing any suicidality), and examined for sociodemographic differentials using normalised sampling weights. For each of the 12 surveyed states, we calculated the age-standardised suicidality prevalence for men and women, men-to-women ratio of weighted suicidality prevalence, ratio of suicidality to suicide deaths, and ratio of suicide attempts to suicide deaths. We used logistic regression analysis to examine the association between sociodemographic factors and overall suicidality and severity. FINDINGS: Among 34 748 participants with complete interviews, 5·1% (95% CI 4·7-5·6) had some level of suicidality, and 0·3% (0·2-0·4) had at least one suicide attempt in the past month. The prevalence of overall suicidality was higher in women (6·0% [5·4-6·6]) than in men (4·1% [3·7-4·6]). The prevalence of overall suicidality was highest in those aged 40-49 years among women and in those aged 60 years or older among men. Compared with their counterparts, individuals with lower educational attainment, individuals residing in urban metropolitan cities, individuals who were widowed, separated, or divorced, and unemployed individuals had a higher prevalence of overall suicidality. The men-to-women ratio of overall suicidality prevalence for India was 0·68 (range 0·55-0·85). For every death by suicide in India, there were more than 200 people with suicidality and more than 15 suicide attempts. We found variations for various severities of suicidality. We found an increased risk for overall suicidality in women versus men (odds ratio [OR] 1·54 [95% CI 1·31-1·81]; p<0·0001) and in individuals residing in urban metropolitan cities versus those residing in rural areas (1·75 [1·30-2·35]; p=0·0002). Individuals belonging to the lowest income quintile (reference group with OR <1·00 and p<0·05 for other income quintiles), those with depressive disorders (28·78 [20·04-41·33]; p<0.0001) and those with alcohol use disorders (6·52 [3·83-11·10]; p<0.0001) had an increased risk for high suicidality, compared with their corresponding counterparts. INTERPRETATION: A national suicide prevention strategy that is comprehensive, using multisectoral approaches, is required to address the prevailing sociodemographic and other risk factors for reducing suicidality and suicide deaths in India. This study also has implications for other low-income and middle-income countries in south Asia, where sociodemographic factors play a crucial role for suicide prevention. FUNDING: Ministry of Health and Family Welfare, Government of India.

Prevalence and socioeconomic impact of depressive disorders in India: multisite population-based cross-sectional study.

OBJECTIVES: The National Mental Health Survey (NMHS) of India was undertaken with the objectives of (1) estimating the prevalence and patterns of various mental disorders in representative Indian population and (2) identifying the treatment gap, healthcare utilisation, disabilities and impact of mental disorders. This paper highlights findings pertaining to depressive disorders (DD) from the NMHS. DESIGN: Multisite population-based cross-sectional study. Subjects were selected by multistage stratified random cluster sampling technique with random selection based on probability proportionate to size at each stage. SETTING: Conducted across 12 states in India (representing varied cultural and geographical diversity), employing uniform, standardised and robust methodology. PARTICIPANTS: A total of 34 802 adults (>18 years) were interviewed. MAIN OUTCOME MEASURE: Prevalence of depressive disorders (ICD-10 DCR) diagnosed using Mini International Neuropsychiatric Interview V.6.0. RESULTS: The weighted prevalence of lifetime and current DD was 5.25% (95% CI: 5.21% to 5.29%, n=34 802) and 2.68% (95% CI: 2.65% to 2.71%, n=34 802), respectively. Prevalence was highest in the 40-59 age groups (3.6%, n=10 302), among females (3.0%, n=18 217) and those residing in cities with population >1 million (5.2%, n=4244). Age, gender, place of residence, education and household income were found to be significantly associated with current DD. Nearly two-thirds of individuals with DD reported disability of varying severity, and the treatment gap for depression in the study population was 79.1%. On an average, households spent INR1500/month (~US$ 23.0/month) towards care of persons affected with DD. CONCLUSION: Around 23 million adults would need care for DD in India at any given time. Since productive population is affected most, DD entails considerable socioeconomic impact at individual and family levels. This is a clarion call for all the concerned stakeholders to scale up services under National Mental Health Programme in India along with integrating care for DD with other ongoing national health programmes.

An Indian, Comic-based, Online-EEG Paradigm for Theory of Mind: An Exploratory, Pilot Study on Schizophrenia Patients.

BACKGROUND: False-belief (FB) tasks are used to assess the theory of mind (ToM) functioning, which has been found to be impaired in schizophrenia. FB task stimuli used so far in neuroimaging studies in schizophrenia have been sentence-based ones. We aimed to validate an Indian, colour-comic based FB task by using an online-electroencephalogram (EEG) paradigm discriminating schizophrenia patients and healthy controls. MATERIALS AND METHODS: Fifteen schizophrenia patients and 15 healthy controls performed online FB task during a 256-channel-EEG recording. 'Content' and 'known-groups' validity were examined using offline behavioural measures. Evoked gamma spectral-power in four regions of interest (ROIs) was compared between groups. Social functioning was also assessed. RESULTS: Strength of classifying the groups was significant for both the number of correct responses and the reaction-times on the FB tasks. Social functioning was found to be poorer in patients. On the comparative analysis of evoked gamma spectral-power in the ROIs, very small effect size and observed power were noted. CONCLUSION: 'Content' and 'known-groups' validity of the culturally undermined comic-based FB task are good. Our findings reiterate that ToM functioning is impaired in schizophrenia. Our results were inconclusive in inferring whether evoked gamma spectral-power could be used as a neural validator for poor ToM functioning.

History of psychiatry: An Indian perspective.

A knowledge of history becomes important in learning the way concepts have evolved and how they are understood in different and conflicting traditions in psychiatry. Modern psychiatry and its history has always been observed through the prism of western science which has its own evolutionary line in which the eastern sciences can't fit and are always at a disadvantage. Especially the colonial bid to prove its legitimacy as a civilizing mission led to representation of European medicine as morally superior to the eastern practices resulting in a biased history. Though in reality, the history of psychiatry is heterogeneous and consists of many different scientific and cultural traditions which vary between populations. hence the Indian concept of "unmada" can't be compared or conformed to "schizophrenia" without addressing its cultural and historical contexts. Many suggest that in case of Indian patients, an understanding of illness through a Vedantic model of psych seems more appealing in comparison to the western constructs, as such an attitude has been transferred over generations. Therefore, a knowledge of history of psychiatry, especially from an Indian perspective becomes important.

National Mental Health Survey of India, 2016 - Rationale, design and methods.

Understanding the burden and pattern of mental disorders as well as mapping the existing resources for delivery of mental health services in India, has been a felt need over decades. Recognizing this necessity, the Ministry of Health and Family Welfare, Government of India, commissioned the National Mental Health Survey (NMHS) in the year 2014-15. The NMHS aimed to estimate the prevalence and burden of mental health disorders in India and identify current treatment gaps, existing patterns of health-care seeking, service utilization patterns, along with an understanding of the impact and disability due to these disorders. This paper describes the design, steps and the methodology adopted for phase 1 of the NMHS conducted in India. The NMHS phase 1 covered a representative population of 39,532 from 12 states across 6 regions of India, namely, the states of Punjab and Uttar Pradesh (North); Tamil Nadu and Kerala (South); Jharkhand and West Bengal (East); Rajasthan and Gujarat (West); Madhya Pradesh and Chhattisgarh (Central) and Assam and Manipur (North East). The NMHS of India (2015-16) is a unique representative survey which adopted a uniform and standardized methodology which sought to overcome limitations of previous surveys. It employed a multi-stage, stratified, random cluster sampling technique, with random selection of clusters based on Probability Proportionate to Size. It was expected that the findings from the NMHS 2015-16 would reveal the burden of mental disorders, the magnitude of the treatment gap, existing challenges and prevailing barriers in the mental-health delivery systems in the country at a single point in time. It is hoped that the results of NMHS will provide the evidence to strengthen and implement mental health policies and programs in the near future and provide the rationale to enhance investment in mental health care in India. It is also hoped that the NMHS will provide a framework for conducting similar population based surveys on mental health and other public health problems in low and middle-income countries.

Prevalence of Obsessive-Compulsive Spectrum Disorders in Obsessive-Compulsive Disorder.

INTRODUCTION: There is growing awareness of the heterogeneity of obsessive-compulsive disorder (OCD) and of the multiple systems involved in its pathogenesis. Identification of obsessive-compulsive spectrum disorders (OCSDs) may have important implications in the management and prognosis of OCD, but there is a paucity of research in the domain of identification of OCSD in probands with OCD. There are few studies that have examined OCSD in the first-degree relatives (FDR) of OCD patients, some of these were not controlled, and these studies have no final agreements over outcomes, and therefore, this area needs to be further explored. OBJECTIVES: The objective of this study was to assess the prevalence of OCSDs in OCD probands; and its relationship to sociodemographic and clinical variables, comparing each aspect by a control group of schizophrenia probands. MATERIALS AND METHODS: Sixty patients each of OCD and schizophrenia, diagnosed by the Diagnostic and Statistical Manual of Mental Disorders IV Text Revision,[1] above 18 years of age and giving informed consent, were interviewed using the Structured Clinical Interview for OCSD, Yale-Brown Obsessive-Compulsive Rating Scale, Hamilton Rating Scale for Depression, and Hamilton Rating Scale for Anxiety. RESULTS: In OCD group, 22 OCSDs were found in 11 subjects whereas in schizophrenia group, 2 OCSDs (self-injury) were found in two probands. When the two groups were compared in terms of individual OCSDs, there was no significant difference between them. However, when the comparison was made taking into account all OCSDs taken together, it was significantly higher (P = 0.016) in the OCD group compared to the schizophrenia group. CONCLUSION: OCSDs were significantly more in OCD probands as compared to schizophrenia probands. This suggests a familial aggregation of these disorders.

Functional Impairment and Quality of Life in Patients with Obsessive Compulsive Disorder.

BACKGROUND: This study was carried out to enumerate the level of difference in functional impairment and quality of life (QOL) in obsessive-compulsive disorder (OCD) patients and normal control group to find out the relationship among ICD functional impairment and QOL. METHODOLOGY: Thirty patients diagnosed with OCD as per International Classification of Diseases Diagnostic Criteria for Research-10 were taken for study. The control group consists of 30 normal participants from the community. Functional impairment and QOL questionnaires were administered on both groups to measure functional impairment and QOL in OCD. RESULTS: The mean age of onset of OCD was (23.8 ± 7.25), mean duration of illness was (6.3 ± 4.47), and mean duration of treatment was (2.56 ± 2.47). It was also observed that total score as well as all the domains of the World Health Organization QOL-BREF, OCD patients scored significantly less (P < 0.001) compared to normal controls. Dysfunctional Analysis Questionnaire (DAQ)-Social area and DAQ-Personal area had statistically significant positive correlation (P < 0.05) with an obsessive subscale of Yale-Brown Obsessive Compulsive Scale (Y-BOCS) whereas DAQ-social area (P < 0.05), DAQ-Personal Area (P < 0.05) had statistically significant positive correlation with a total score of Y-BOCS. CONCLUSION: The presence of functional impairment leads to poor QOL in the persons with OCD.

Inpatient Suicide in a Psychiatric Hospital: A Nested Case-control Study.

OBJECTIVE: Risk factors for inpatient suicide are different from those in the general population. We examined sociodemographic and clinical variables of patients who committed suicide as an inpatient in a psychiatric hospital in India. METHODS: Matched retrospective nested case-control design was adopted. Ten patients who died by suicide as inpatients between 2000 and 2013 were included, along with fifty controls, matched with respect to age, sex, diagnosis, and period of admission. RESULTS: Suicide completers were mostly unskilled in occupation (P = 0.03), had a history of past suicide attempts (P < 0.001), shorter duration of hospital stay (P = 0.001), poorer improvement on psychopathology (P = 0.02), and were having more suicidal ideation (P = 0.02). Significantly more completers were receiving antidepressants (P = 0.04). CONCLUSION: This study adds to the existing sparse literature on inpatient suicides from Asia. Strength of the study was close matching between case and controls and blindedness. Limitations were retrospective design, and variations in prescription behavior and treatment decisions.

Sources of mu activity and their functional connectivity in perceiving complexities in reciprocal social interactive motion: An exploratory study using the 'Namaste' task.

Cognitive processes underlying reciprocal social interactions are understood by the mechanism of embodiment, which is closely related to the mirror neuron system. Electroencephalographic (EEG) mu activity is a neural marker of the mirror neuron system. This study investigated the mu activity, localization of its sources and functional connectivity, which was induced while watching reciprocal social interactive motion across various degrees of complexity. Eighteen healthy participants underwent high-resolution EEG recording using 256-channels while they watched a specifically designed, culture specific, video task that showed two persons interacting socially using body gestures. Task complexity was determined by (1) whether there was an identical gestural response or a non-identical one; (2) whether the participant watched two persons interacting or was virtually involved in the interaction. Source localization and functional connectivity analysis was conducted for mu activity across various tasks. We also correlated mu activity and functional connectivity measures with serum BDNF. We found that spectral densities in various brain sources of mu activity and their increased functional connectivity distinguished identical and non-identical reciprocal expression observations, while mu suppression alone did not discriminate various degrees of complexities. These findings might have important implications in the understanding of mechanisms underlying mirror neuron dysfunction in various psychiatric disorders.

Efficacy of ranitidine in olanzapine-induced weight gain: a dose-response study.

AIM: Weight gain has long been recognized as a side-effect of atypical antipsychotic drugs. Numerous new approaches have been tried for prevention of weight gain, the H2 blockers being one of them. The study was conducted with the aim to evaluate the efficacy of ranitidine in olanzapine-induced weight gain at two fixed doses of 150 and 300 mg day-1 . METHODS: Seventy-five inpatients with an ICD-10-DCR diagnosis of schizophrenia as their first episode were randomized into three groups of 25 patients each, receiving 150 mg day-1 ranitidine, 300 mg day-1 ranitidine and third group receiving only olanzapine. Their weight and body mass index (BMI) were measured at baseline and at intervals of 4 and 8 weeks. RESULTS: All patients were comparable with respect to their weight and BMI at baseline. When a change in the weight and BMI was assessed at 4 and 8 weeks from baseline, no significant difference was observed between the three groups. CONCLUSION: Ranitidine at doses of 150 and 300 mg day-1 when combined with olanzapine was ineffective in attenuating olanzapine-induced weight gain. The likely reasons could be the use of low doses for a shorter period of time, or mechanisms other than H2 receptors might play an important role in weight gain.