Physiological and metabolic responses to work in heat with graded hypohydration in tropical subjects

Summary Studies were conducted on 25 healthy male volunteers aged 20–25 years drawn randomly from the tropical regions of India. The subjects initially underwent an 8 day heat acclimatization schedule with 2 hours moderate work in a climatic chamber at 45° C DB and 30% RH. These heat acclimatized subjects were then hypohydrated to varying levels of body weight deficits, i.e. 1.3±0.03, 2.3±0.04 and 3.3±0.04%, by a combination of water restriction and moderate exercise inside the hot chamber. After 2 hours rest in a thermoneutral room (25±1° C) the hypohydrated subjects were tested on a bicycle ergometer at a fixed submaximal work rate (40 W, 40 min) in a hot dry condition (45°C DB, 30% RH, 34° C WBGT). Significant increases in exercise heart rate and oral temperature were observed in hypohydrated subjects as compared to euhydration. Sweat rate increased with 1% and 2% hypohydration as compared to euhydration, but a significant decrease was observed with 3% hypohydration. Na⁺ & K⁺ concentrations in arm sweat increased with increase in the level of hypohydration. Oxygen consumption increased significantly only when hypohydration was about 2% or more. It appears that the increased physiological strain observed in tropical subjects working in heat with graded hypohydration is not solely due to reduced sweat rates.     

Cytopathology of uncommon malignant renal neoplasms in the pediatric age group

Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration.Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy.     

HPV DNA in plasma of patients with cervical carcinoma.

BACKGROUND: HPV DNA has been detected in metastatic tumour and HPV plasma viraemia may indicate a poor prognosis and a high risk for metastasis. OBJECTIVE: Detection of HPV DNA in plasma of patients with cervical carcinoma. STUDY DESIGN: A cross-sectional study was done, wherein cervical biopsies and plasma samples were collected from 58 women with invasive cervical carcinoma, 10 women with cervical intraepithelial neoplasia (CIN) and 30 control women in the same age range. Polymerase chain reaction (PCR) was employed to detect the presence of HPV DNA. Samples positive for HPV DNA were typed by restriction fragment length polymorphism (RFLP). To confirm that the HPV sequence in plasma was identical to that in tissue, sequencing was done on all the paired plasma and tissue samples. RESULTS: All the 30 paired cervical tissue and plasma samples from the controls were negative for HPV DNA. HPV DNA was detectable in cervical tissues of 55 (94.8%) of 58 patients with invasive cervical carcinoma and in all 10 patients (100%) with CIN and in eight (11.8%) of the total 68 plasma samples from patients. All eight plasma samples were from women with invasive cervical carcinoma with three each in stages IIIB and IV and one each in stages IIB and IB, respectively. Of the eight positive samples, seven were typed as HPV-16 and 1 as HPV-58. HPV types detected in cervical tissue and plasma pairs from these eight patients correlated as revealed by RFLP and sequencing. A patient with stage IB cancer had detectable HPV DNA in the external iliac lymph node, removed at Wertheims hysterectomy, which was histopathologically free of tumour. The HPV type in the node, was the same as that present in the paired tissue and plasma sample. CONCLUSIONS: HPV DNA is detectable in the plasma of patients with advanced cervical cancer.     

Evaluation of modified passive haemagglutination assay for Vi antibody estimation in Salmonella typhi infections.

A simple passive haemmagglutination assay (PHA) was developed to detect Vi antibodies, to improve the diagnosis of typhoid fever by small laboratories. The Vi capsular antigen of Salmonella typhi was extracted by alternate alcohol and acetone precipitation. Formalin fixed, sheep red blood cells treated with chromium chloride were sensitised with this Vi antigen and antibodies detected and measured by PHA. The test had a sensitivity of 83.3% among 30 cases of typhoid fever confirmed by culture. The specificity of the test was 94%, making it suitable for use in laboratories without facilities for IFAT or ELISA.     

Reflectance confocal microscopy evaluation of pigmented lesions on tattooed skin

Lasers in Medical Science - The evaluation of pigmented lesions on tattooed skin poses a diagnostic challenge for dermatologists, as a nevus may be partially or completely obscured by tattoo...     

Radiation therapy induced changes in apoptosis and its major regulatory proteins, Bcl-2, Bcl-XL, and Bax, in locally advanced invasive squamous cell carcinoma of the cervix.

BACKGROUND AND PURPOSE: Radiation therapy (RT) for cancer induces cell death by apoptosis. The major apoptotic regulatory molecules include Bcl-2, Bcl-XL (antiapoptotic), and Bax (proapoptotic) proteins. Invasive squamous cell carcinoma of the cervix is mainly treated by radiation, and hence our aim was to evaluate the changes induced by RT in the apoptotic index (AI) and to correlate this to the levels of the major pro- and antiapoptotic molecules. MATERIALS AND METHODS: Paired biopsies were obtained in 30 cases of invasive carcinoma cervix before and after 10 Gy RT. The TUNEL assay was performed to detect apoptotic nuclei and Bcl-2, Bcl-XL, and Bax proteins detected by immunohistochemistry (IHC). Statistical analysis was performed using the Spearman rank correlation coefficient test. RESULTS: Following RT, there was a significant increase in the mean AI [2.25 (+/-2.28) in post-RT vs 0.90 (+/-0.53) in the pre-RT group]. Bax, a major proapoptotic protein, was significantly increased following RT (P < 0.05), whereas the antiapoptotic Bcl-XL showed a significant decrease (P = 0.006). There was no significant change in Bcl-2 expression. The Bcl-2 and Bax IHC scores and the Bcl-2/Bax ratio did not correlate with AI in the 2 groups. There was an inverse correlation of Bcl-XL to AI in the pre-RT group (P = 0.003) but not in the post-RT group. CONCLUSIONS: RT for invasive squamous cell carcinoma of cervix results in increased apoptotic cell death with the up-regulation of Bax, a proapoptotic protein, and the down-regulation of Bcl-XL, an antiapoptotic protein, without any significant change in the levels of Bcl-2.     

Examining changes in students' perception of science relevancy and their career aspirations: Integrating sustainability-oriented socio-scientific issues into general chemistry curriculum

Making science relevant to students' lives, future careers, or societies by introducing controversial socio-scientific issues in classrooms motivates students to take more active roles in learning science. This study explored the influence of integrating two sustainability-oriented socio-scientific issues (SOS₂Is) - alternative energies and nanotechnology-into the General Chemistry curriculum on 743 students' career aspirations and perceptions of science relevancy. For the presentation of topics, two learning environments on Prezi were prepared. The participants were guided to explore these learning environments that focused on pros and cons of each topic, including environmental and health hazards of technological developments. In addition, students were encouraged to link these discussions to sustainability issues in the context of the UN SDGs. The analysis of Changes in Attitude Towards the Relevancy of Science and Career Aspirations surveys indicated that the interventions improved students' perception of science relevancy and altered their career aspirations in many areas, regardless of their socioeconomic status and ethnic background. This study provides empirical evidence for the effectiveness of discussions around socio-scientific issues in changing students’ perceptions of science and career aspirations and recommends practical methods to encourage students to become global and scientifically literate citizens.