Larger spleens and greater splenic contraction during exercise may be an adaptive characteristic of Nepali Sherpa at high-altitude.

OBJECTIVES: The Sherpa ethnic group living at altitude in Nepal may have experienced natural selection in response to chronic hypoxia. We have previously shown that Sherpa in Kathmandu (1400 m) possess larger spleens and a greater apnea-induced splenic contraction compared to lowland Nepalis. This may be significant for exercise capacity at altitude as the human spleen responds to stress-induced catecholamine secretion by an immediate contraction, which results in transiently elevated hemoglobin concentration ([Hb]). METHODS: To investigate splenic contraction in response to exercise at high-altitude (4300 m; Pb = ~450 Torr), we recruited 63 acclimatized Sherpa (29F) and 14 Nepali non-Sherpa (7F). Spleen volume was measured before and after maximal exercise on a cycle ergometer by ultrasonography, along with [Hb] and oxygen saturation (SpO2). RESULTS: Resting spleen volume was larger in the Sherpa compared with Nepali non-Sherpa (237 ± 62 vs. 165 ± 34 mL, p < .001), as was the exercise-induced splenic contraction (Δspleen volume, 91 ± 40 vs. 38 ± 32 mL, p < .001). From rest to exercise, [Hb] increased (1.2 to 1.4 g.dl-1), SpO2 decreased (~9%) and calculated arterial oxygen content (CaO2) remained stable, but there were no significant differences between groups. In Sherpa, both resting spleen volume and the Δspleen volume were modest positive predictors of the change (Δ) in [Hb] and CaO2 with exercise (p-values from .026 to .037 and R2 values from 0.059 to 0.067 for the predictor variable). CONCLUSIONS: Larger spleens and greater splenic contraction may be an adaptive characteristic of Nepali Sherpa to increase CaO2 during exercise at altitude, but the direct link between spleen size/function and hypoxia tolerance remains unclear.

Differential splenic responses to hyperoxic breathing at high altitude in Sherpa and lowlanders.

The human spleen contracts in response to stress-induced catecholamine secretion, resulting in a temporary rise in haemoglobin concentration ([Hb]). Recent findings highlighted enhanced splenic response to exercise at high altitude in Sherpa, possibly due to a blunted splenic response to hypoxia. To explore the potential blunted splenic contraction in Sherpas at high altitude, we examined changes in spleen volume during hyperoxic breathing, comparing acclimatized Sherpa with acclimatized individuals of lowland ancestry. Our study included 14 non-Sherpa (7 female) residing at altitude for a mean continuous duration of 3 months and 46 Sherpa (24 female) with an average of 4 years altitude exposure. Participants underwent a hyperoxic breathing test at altitude (4300 m; barrometric pressure = âˆ¼430 torr; P O 2 ${P_{{{\mathrm{O}}_{\mathrm{2}}}}}$  = âˆ¼90 torr). Throughout the test, we measured spleen volume using ultrasonography and monitored oxygen saturation ( S p O 2 ${S_{{\mathrm{p}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ). During rest, Sherpa exhibited larger spleens (226 ± 70 mL) compared to non-Sherpa (165 ± 34 mL; P < 0.001; effect size (ES) = 0.95, 95% CI: 0.3-1.6). In response to hyperoxia, non-Sherpa demonstrated 22 ± 12% increase in spleen size (35 ± 17 mL, 95% CI: 20.7-48.9; P < 0.001; ES = 1.8, 95% CI: 0.93-2.66), while spleen size remained unchanged in Sherpa (-2 ± 13 mL, 95% CI: -2.4 to 7.3; P = 0.640; ES = 0.18, 95% CI: -0.10 to 0.47). Our findings suggest that Sherpa and non-Sherpas of lowland ancestry exhibit distinct variations in spleen volume during hyperoxia at high altitude, potentially indicating two distinct splenic functions. In Sherpa, this phenomenon may signify a diminished splenic response to altitude-related hypoxia at rest, potentially contributing to enhanced splenic contractions during physical stress. Conversely, non-Sherpa experienced a transient increase in spleen size during hyperoxia, indicating an active tonic contraction, which may influence early altitude acclimatization in lowlanders by raising [Hb].

Advantage of neuroeducation in managing mass psychogenic illness among rural school children in Nepal.

Introduction: Mass psychogenic illness (MPI), also known as mass hysteria (MH), is a mental health disorder that frequently occurs in Nepal. It primarily affects female students in government high schools and occurs during the course of the school day over a few days without corresponding organic causes. Purpose of the study: This study set out to evaluate and give neuroeducation with the goal of preventing and/or managing MPI after documenting the existing state of knowledge regarding MPI. Materials and methods: A total of 234 female students in grades 6 through 10 who attended MH-affected schools (SMH, n = 119) and schools without a mass hysteria history (SNOMH, n = 114) participated in this mass hysteria awareness study. Participants received written pre- and posttests formatted as questionnaires before and after receiving neuroeducation by watching a drama, viewing a human brain-spinal cord model demonstration, and attending an instructive lecture on the human neurological system, stress, and mass hysteria. Results: Our neuroeducation awareness study on mass hysteria was found to be effective among all of the participants from both SMH and SNOMH. The results indicated that the aforementioned neuroeducation tools are more effective in improving knowledge about mental stress differently in different grades of SMH and SNOMH students. The basic understanding of the human neurological system was not improved by the neuroeducation tool, according to our findings. Conclusion: Our study suggests that using day-structured neuroeducational tools might be an efficient way to treat mass psychogenic illness in Nepal.

Prevalence of migraine and tension-type headache among undergraduate medical students of Kathmandu Valley: A cross-sectional study.

Background: Headache is the most prevalent neurological symptom which can be of a serious condition, as in brain tumor, but mostly it is a benign condition that includes primary headache such as migraine or tension-type headache (TTH). Migraine reoccurs frequently and is more severe but owing to the high prevalence of TTH, however, impaired quality of life due to TTH is greater than that of migraine at the population level. Medical students are constantly subjected to stress and in such a condition, it was necessary to find out the burden of headache among medical students. This cross-sectional study done among medical students aims to generate some data and literature which will change the outlook of stakeholders towards headache disorders among medical students. Methods: This cross-sectional study is based upon Headache Screening Questionnaire-English Version questionnaire based upon the ICHD-3 beta criteria. Medical students of Kathmandu valley were sampled by using convenient sampling and data were collected. Data were refined in Microsoft Excel and imported to SPSS 20 for analysis. Results: A total of 352 individuals were part of this study, out of which 229 (65.1%) were males and 123 (34.9%) were females with a mean age of 21.72 ± 1.601 years (mean ± SD). Prevalence of migraine and TTH was found to be 15.3% (95% confidence interval [CI]: 11.7%-19.3%) and 40.3% (95% CI: 34.9-45.2), respectively. Through multivariate binomial regression, it was observed that the odds of being diagnosed with migraine increased with age (adjusted odds ratio [AOR] = 1.266 [1.013-1.583], p = 0.038), females had twice the odds of experiencing migraine headaches compared to males (AOR = 2.119 [1.074-4.180], p = 0.03), and medical students who stayed at the hostel were at lesser odds of experiencing migraine headache (AOR = 2.772 [1.501-5.118], p = 0.01). Conclusion: Prevalence of migraine and TTH among undergraduate medical students was found to be 15.3% and 40.3%, respectively.

Knowledge Regarding Blood Pressure Measurement among First and Second Year Undergraduate Medical Students: A Descriptive Cross-sectional Study.

Introduction: Blood pressure measurement has a great implication in medicine. Every medical personnel should have a sound knowledge regarding blood pressure measurement. This study was conducted with the aim of determining the knowledge regarding blood pressure measurement among first and second year medical students of a medical college. Methods: A descriptive cross-sectional study was conducted by Department of Physiology of Nepalese Army Institute of Health Sciences from June to December 2021 after receiving the ethical approval from Institutional Review Committee with registration number 394. One hundred ninety-seven students from first and second year were included in the study using whole sampling technique. Data was entered and analysed using Microsoft Excel 2019 and Statistical Package for Social sciences version 16.0. Descriptive statistics like frequency, percentage for binary data and mean, standard deviation for continuous data were calculated. Results: Among 197 students from first and second year, 175 (88.83%) had satisfactory knowledge regarding blood pressure measurement with score ≥8 in Objective Structured Practical Examination. Eighty five (85.86%) students from first year and 90 (91.84%) students from second year had scores ≥8, hence had satisfactory knowledge on blood pressure measurement. A total of 18 (18.18%) first year students achieved a score of 10, while 24 (24.49%) students of the second year scored 12, which were the modal score. Conclusions: The proportion of first and second year students having satisfactory knowledge regarding blood pressure measurement is higher in our study. Keywords: blood pressure; knowledge; medical students.

Oxytocin is indispensable for conspecific-odor preference and controls the initiation of female, but not male, sexual behavior in mice.

Oxytocin (OT) has been demonstrated to be involved in various social behaviors in mammals. However, OT gene knockout (OTKO) mice can conceive and deliver successfully, though females cannot rear their pups because of lack of lactation. Here, we investigated the sociosexual behavior of both sexes in two experimental setups: olfactory preference for sexual partner's odor and direct social interaction in an enriched condition. In the preference test, mice were given a choice of two airborne odors derived from intact male and receptive female mice, or from intact or castrated male mice. Wild-type (WT) mice significantly preferred opposite-sex odors, whereas OTKO mice showed vigorous but equivalent exploration to all stimuli. In social interactions in the enriched condition, no difference in sexual behavior was found between WT and OTKO males. In contrast, WT female initiated sexual behavior at the second week test, while OTKO females required 4 weeks to receive successful mounts. Neuronal activation by odor stimulation was compared between WT and OTKO mice. The numbers of cFos-immunoreactive cells increased in the medial amygdala and the preoptic area after exposure to opposite-sex odors in WT mice, whereas the increase was suppressed in OTKO mice. We conclude that OT plays an important role in the regulation of olfactory-related social behavior in both male and female mice. The influence of OT was greater in female mice, especially during social interactions involving the acquisition of sexual experience.

Neuroscience Symposium and Workshop on SAAPCON-2016, Nepal.

Physiological Society of Nepal, with support from the South Asian Association of Physiologists (SAAP), organized the 5th Biennial Conference of the South Asian Association of Physiologists in conjunction with the 2nd Annual Conference of Physiological Society of Nepal. The purpose of this conference is to bring the scientists, researchers, and students from the South Asian countries in one platform to share and discuss the recent advances and achievements in the field of physiology. Since physiology is the backbone of medical science which deals with the functions of the human body, the theme of the conference was given as "Redefining health in nature." Giving the emphasis on this theme, the conference was organized on November 10-14, 2016, in Kathmandu University, Dhulikhel, Nepal. A total of 300 participants from 15 countries including the South Asian Association of Regional Cooperation (SAARC) and Non-SAARC countries participated in the conference. The scientific program of main conference, which ran for 2 days, was divided into 7 symposia - neuroscience, cardiopulmonary physiology, cellular and integrative physiology, health and lifestyle, role of physiology and medical education, endocrine and reproductive physiology, and high altitude and respiratory physiology - to highlight the latest progresses made in the field of physiology around the globe. Neuroscience symposium held on the second day consisted of 7 advance lectures and 3 young scientist presentations and poster session. Post-conference workshop on system neuroscience was held in BP Koirala Institute of Health Sciences, Dharan, Nepal.

Olfactory preference in the male rat depends on multiple chemosensory inputs converging on the preoptic area.

Both volatile and nonvolatile molecules are involved in chemosensory communication in rodents. Volatile odors from physically inaccessible estrous females induced increased numbers of c-Fos-positive cells in the preoptic area (POA) and in the cortical nucleus of the amygdala (CoA) of male rats. The numbers of c-Fos-positive cells in the medial nucleus of the amygdala (MeA) increased in response to the nonvolatile odors of bedding soiled with the excreta of estrous females. In an alternate choice paradigm, male rats carrying ibotenic acid lesions in either the MeA or the CoA--or a combination of both--distinguished the odors of estrous females from those of males, although the time spent sniffing the stimuli was diminished. Males with POA lesions showed complete loss of this capability. Males carrying either of the lesions did not detect differences between estrous and anestrous females or between intact and orchidectomized males. Lesions in the POA or MeA severely impaired male sexual behavior, whereas a CoA lesion had no effects. Thus, c-Fos-positive cells in the CoA might be involved in chemosensory transmission relevant to certain social contexts, but not in the execution of male sexual behavior. The POA is indispensable for both olfactory preferences and sexual behavior. The residual olfactory preference in males with MeA or CoA lesions or the combination of both could reflect an additional route for chemosensory transmission from the main olfactory bulb to the POA.

Knowledge attitude and practice (KAP) study regarding facts for life.

This knowledge attitude and practice (KAP) study was done in the married women of age 18-38 years in Jorpati and Gokarna village development committees of Katmandu district to evaluate the knowledge of "Facts for Life". There were 510 married women involved in this study. Altogether 28 questions were asked to each of them regarding the "Facts for Life". It includes the following five subjects: Safe motherhood, Childhood Immunization, Childhood diarrhea, Acute Respiratory Infection (ARI) in childhood and hygiene. There was a significant increase in knowledge about hygiene and knowledge regarding childhood immunization than diarrhea, ARI and Safe motherhood. Results showed that the overall knowledge was at 62.8%. This shows that still more attention is needed to Nepalese women.