Escape from the renal actions of vasopressin is said to occur in rats with chronic hyponatremia. Our objective was to provide specific evidence to test this hypothesis. Hence the osmolality in the excised renal papilla and in simultaneously voided urine (U(Osm)) was measured in rats with and without hyponatremia. To induce hyponatremia, rats were fed low-electrolyte chow for 6 days. In the first 3 days, water was provided ad lib. On days 4 to 6, a long acting vasopressin preparation (dDAVP) was given every 8 hours to induce water retention. The hyponatremic rats drank 21 mL 5% sucrose on day 4 and 6 mL on day 5. On the morning of day 6, these rats were given 10 mL of 5% glucose in water (D5W) by the intraperitoneal route at 09:00 hour and at 11:00 hour. Analyses were performed in blood, urine, and the excised renal papilla at 13:00 hour on day 6. The concentration of Na+ in plasma (P(Na)) in rats without intraperitoneal D5W was 140+/-1 mEq/L (n=7) whereas it was 112+/-3 mEq/L in the hyponatremic group (n=12). The hyponatremic rats had a higher osmolality in the excised papillary (1,915+/-117 mOsm/kg H2O) than the U(Osm) (1,528+/-176 mOsm/kg H2O, P<0.05). One explanation for this difference is that the rats escaped from the renal action of vasopressin. Nevertheless, based on a quantitative analysis, other possibilities will be considered.
Animals ; Aquaporins ; Glucose ; Hyponatremia ; Osmolar Concentration ; Plasma ; Rats ; Retention (Psychology) ; Sucrose ; United Nations ; Vasopressins ; Water

When the concentration of sodium (Na+) in arterial plasma (P(Na)) declines sufficiently to inhibit the release of vasopressin, water will be excreted promptly when the vast majority of aquaporin 2 water channels (AQP2) have been removed from luminal membranes of late distal nephron segments. In this setting, the volume of filtrate delivered distally sets the upper limit on the magnitude of the water diuresis. Since there is an unknown volume of water reabsorbed in the late distal nephron, our objective was to provide a quantitative assessment of this parameter. Accordingly, rats were given a large oral water load, while minimizing non-osmotic stimuli for the release of vasopressin. The composition of plasma and urine were measured. The renal papilla was excised during the water diuresis to assess the osmotic driving force for water reabsorption in the inner medullary collecting duct. During water diuresis, the concentration of creatinine in the urine was 13-fold higher than in plasma, which implies that ~8% of filtered water was excreted. The papillary interstitial osmolality was 600 mOsm/L > the urine osmolality. Since 17% of filtered water is delivered to the earliest distal convoluted tubule micropuncture site, we conclude that half of the water delivered to the late distal nephron is reabsorbed downstream during water diuresis. The enormous osmotic driving force for the reabsorption of water in the inner medullary collecting duct may play a role in this reabsorption of water. Possible clinical implications are illustrated in the discussion of a case example.
Animals ; Aquaporin 2 ; Aquaporins ; Creatinine ; Diuresis ; Membranes ; Nephrons ; Osmolar Concentration ; Permeability ; Phenobarbital ; Plasma ; Polyuria ; Punctures ; Rats ; Sodium ; Vasopressins ; Water

Attitude ; Education, Medical, Undergraduate ; Follow-Up Studies ; Humans ; Longitudinal Studies ; Radiology ; Students, Medical ; Surveys and Questionnaires

INTRODUCTIONThe aims of the study were to identify the prevalence and sociodemographic and clinical correlates of suicidal behaviours using data from a cross-sectional survey among those with major depressive disorder (MDD) in Singapore.

MATERIALS AND METHODSThe Singapore Mental Health Study (SMHS) was a cross-sectional epidemiological study that surveyed Singapore residents (Singapore citizens and permanent residents) aged 18 years and above. The assessment of mental disorders was established using version 3.0 of the Composite International Diagnostic Interview (CIDI 3.0). For the purposes of this study, suicidal behaviour was assessed by questions which were asked to respondents who answered positively to the screening questions in the CIDI 3.0 "Depression" module.

RESULTSThe prevalence of suicidal ideation, plan and attempt among those with lifetime MDD was 43.6%, 13.7% and 12.3%, respectively. We found that suicidal ideation, plan and attempt were significantly associated with ethnicity, education and income. The rate of those who had sought some professional help was higher among those with suicidal plan (71.7%) and attempt (72.3%) as compared to those with suicidal ideation (48.7%) and those with MDD but no suicidal behaviour (29%).

CONCLUSIONIndividuals with MDD and suicidal behaviour do differ from their non-suicidal counterparts as they have a different sociodemographic and clinical profile. There is a need for more research and a better understanding of this population which in turn could lead to the development and implementation of relevant interventions.

Adolescent ; Adult ; Aged ; Cross-Sectional Studies ; Depressive Disorder, Major ; complications ; psychology ; Female ; Humans ; Male ; Middle Aged ; Singapore ; Socioeconomic Factors ; Suicidal Ideation ; Suicide, Attempted ; statistics & numerical data ; Young Adult

INTRODUCTIONThis study compares the attitudes between preclinical and clinical medical students towards radiology, following the introduction of a new radiology curriculum for 1st year students.

MATERIALS AND METHODSRevision of the 1st year medical school curriculum for the academic year of 2008/9 with the inclusion of 13 one-hour formal radiology lectures integrated with each body system was done in an undergraduate Southeast Asian medical school. In the old curriculum, 1st and 2nd year medical students are not exposed to radiology. They received limited radiology teaching in their 3rd and 5th years with 2 one-hour lectures as part of their medicine and surgery rotations. In the 4th year, they have a one week non-examinable posting in radiology. A survey was administered to preclinical (new curriculum) and clinical (old curriculum) students. Survey responses were tabulated and attitudes between preclinical and clinical students were compared.

RESULTSMore than half of the preclinical students (155 out of 270 students, 59%) and 90 out of 720 clinical students (12.5%) responded. Students exposed to the new curriculum had attended one or two dedicated radiology lectures and were considering radiology as a clinical elective. Both groups of students did not feel familiar with radiology as with other specialties, were not considering radiology as a career, but felt that radiology was interesting and important to the overall practice of medicine.

CONCLUSIONSExposure of 1st year students to radiology increases their interest in the subject. Further intervention, fi ne-tuning of the curriculum and follow-up surveys will be carried out to see if this interest persists throughout their clinical years.

Attitude of Health Personnel ; Clinical Clerkship ; Clinical Competence ; statistics & numerical data ; Curriculum ; Education, Medical, Undergraduate ; Educational Measurement ; Educational Status ; Health Care Surveys ; Health Knowledge, Attitudes, Practice ; Humans ; Radiology ; education ; Schools, Medical ; statistics & numerical data ; Singapore ; Students, Medical ; psychology ; statistics & numerical data ; Surveys and Questionnaires

INTRODUCTIONPolymerase chain reaction (PCR)-based molecular techniques are useful adjunctive tools in the diagnosis of cutaneous T-cell lymphomas (CTCL). This study compares the sensitivity of PCR analysis of the T-cell receptor-gamma (TCR-gamma) gene rearrangements using conventional polyacrylamide gel electrophoresis (PCR-PAGE) and fluorescent capillary electrophoresis (PCR-FCE).

MATERIALS AND METHODSA total of 22 paraffin blocks were analysed using PCR-PAGE and PCR-FCE. There were 17 cases of mycosis fungoides (MF), 4 cases of non-MF CTCL and 1 case of lymphoblastic leukaemia.

RESULTSComplete agreement was obtained between PCR-PAGE and PCR-FCE in 19 of the 22 cases, giving a concordance rate of 86.4%. PCR-FCE had a higher sensitivity of 77.3%, compared to 63.6% for PCR-PAGE, allowing the detection of 3 additional cases of clonal T-cell rearrangements, which had equivocal or polyclonal bands on PAGE. Two of these 3 cases were in erythrodermic MF patients. PCR-FCE also allowed the detection of matching clones in serial specimens taken from different sites and at different time intervals in patients with MF. However, matching clones from different specimens can be achieved qualitatively in PCR-PAGE by running and comparing these on the same polyacrylamide gel block.

CONCLUSIONSBoth PCR-PAGE and PCR-FCE are useful in detecting T-cell clones in CTCL, with both methods being comparable in sensitivity and showing a high concordance rate of 86.4%. PCR-FCE has the added advantage of exhibiting semiquantitative properties, which may be important in early or erythrodermic MF cases, but the requirement for sophisticated and costly machinery limits its availability to high-capacity laboratories. The well-established PCR-PAGE method is a suitable alternative in routine clinical applications.

Base Sequence ; Electrophoresis, Agar Gel ; Electrophoresis, Capillary ; methods ; Electrophoresis, Polyacrylamide Gel ; Fluorescence ; Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor ; Humans ; Lymphoma, T-Cell ; diagnosis ; Mycosis Fungoides ; Polymerase Chain Reaction ; methods ; Sensitivity and Specificity

Bone health status was investigated in 178 free-living Chinese post-menopausal women in Kuala Lumpur. Body mass index (BMI), body composition (using whole body DXA), calcium intake and serum 25-OH vitamin D status were measured along with biochemical markers of bone turnover, that is, pro-collagen Type 1 N-terminal peptide (P1NP), osteocalcin (OC) and C-telopeptide ß cross link of Type 1 collagen (CTX- β). Bone mineral density (BMD) was measured using DXA (Hologic, USA) at the lumbar spine, femoral neck and total hip. Results showed that osteopenia was present in 50% of the subjects at the spine and 57.9% at the femoral neck. Osteoporosis was diagnosed in 10% of the subjects at both the femoral neck and spine. A total of 29.3% of the subjects had high levels of CTX- ß. Mean serum level of 25-OH vitamin D was 60.4+15.6 nmol/L and 50.6% of the subjects had hypovitaminosis D (defined as <50 nmol/l). Mean total calcium intake of the subjects was 497 + 233 mg, of which only 14% met the RNI for calcium with the additional intake of calcium supplements. Body fat was also significantly correlated (r=0.181, p<0.05) with BMD at the spine but not BMD at the femoral neck. Lean body mass was positively correlated with BMD at the spine (r=0.289, p<0.001) and femoral neck (r=0.295, p<0.001). CTX-β was negatively correlated with BMD at the spine (r= -0.235, p<0.001), whereas P1NP (r=-0.215, p<0.001) and osteocalcin (r=-0.265, p<0.001) were both negatively correlated with BMD at the femoral neck. Generally, the study found that women with osteopenia had higher levels of bone turnover markers, less lean body mass and lower calcium intake than women with normal BMD. In conclusion, this study demonstrated that the majority of free living Chinese post-menopausal women in Kuala Lumpur have low calcium intake, low 25-OH vitamin D status and low bone mass and elevated biochemical markers of bone turnover.

INTRODUCTION: We evaluated the impact of public health measures on paediatric emergency department attendances during the COVID-19 and severe acute respiratory syndrome (SARS) outbreaks in Singapore. METHODS: Between 1 January 2020 and 31 July 2020, we retrospectively reviewed paediatric emergency department attendances and admissions in a tertiary paediatric hospital in Singapore before and after a national lockdown to combat the spread of COVID-19 in Singapore. Hospital attendances and admissions were compared with data from a corresponding period in 2019 (1 January 2019 to 31 July 2019), as well as during and after the SARS outbreak (1 January 2003 to 31 December 2004). RESULTS: Compared with a corresponding non-outbreak period, emergency department attendances decreased in line with nationwide public health measures during the COVID-19 and SARS outbreaks (2020 and 2003 respectively), before increasing gradually following lifting of restrictions, albeit not to recorded levels before these outbreaks. During the COVID-19 outbreak, mean daily attendances decreased by 40%, from 458 per day in January-July 2019, to 274 per day in January-July 2020. The absolute number of hospital inpatient admissions decreased by 37% from January-July 2019 (19,629) to January-July 2020 (12,304). The proportion of emergency department attendances requiring admission remained similar: 20% in January-July 2019 and 21% in January-July 2020. CONCLUSION Nationwide public health measures in Singapore have had an impact on paediatric emergency department attendances and hospital inpatient admissions. Data from this study could inform planning and resource allocation for emergency departments in Singapore and internationally.
Adolescent ; COVID-19/prevention & control* ; Child ; Child, Preschool ; Disease Outbreaks ; Emergency Service, Hospital/trends* ; Facilities and Services Utilization/trends* ; Female ; Health Policy ; Humans ; Infant ; Infant, Newborn ; Male ; Patient Acceptance of Health Care/statistics & numerical data* ; Patient Admission/trends* ; Pediatrics ; Retrospective Studies ; Severe Acute Respiratory Syndrome/epidemiology* ; Singapore/epidemiology*

Androgen insensitivity syndrome is an X-linked recessive condition resulting in a failure of normal masculinization of the external genitalia in a chromosomally male individual. We describe two phenotypically female siblings aged 27 and 18 years, who presented with primary amenorrhea. The older sibling first consulted because of her desire to be pregnant while her younger sibling consulted upon the physician’s advice. Clinical presentation, physical examination, hormonal and imaging studies and a male (46XY) karyotype confirmed the diagnosis of Complete Androgen Insensitivity Syndrome (AIS) in both individuals. Both of them underwent exploratory laparotomy with histopathology confirming presence of immature testicular tissue. Hormone replacement therapy was then started. Both were advised to undergo psychosocial counseling and both chose to be women. This case report is significant since there are only a few local case reports about siblings presenting with this condition.
Androgen-Insensitivity Syndrome ; Karyotyping

Comprehensive quarterly serosurveillance on scrub typhus in small mammals collected from military training sites located near the Demilitarized Zone (DMZ), northern Gyeonggi-do (Province), ROK was conducted to determine the potential rodent-borne and associated ectoparasite disease risks to military personnel. A total of 1,196 rodents and insectivores representing 8 species, Apodemus agrarius (87.3%, n = 1,044), Mus musculus (5.4%, n = 65), Crocidura lasiura (3.3%, n = 40), Microtus fortis (2.6%, n = 31), Micromys minutus (0.3%, n = 4), Tscherskia triton (0.3%, n = 4), Rattus norvegicus (0.3%, n = 4), and Myodes regulus (0.3%, n = 4) were assayed for the presence of antibodies to Orientia tsutsugamushi. O. tsutsugamushi antibodies were detected in 6 of 8 species and seroprevalence determined; A. agrarius (45.6%), M. musculus (23.1%), M. fortis (48.4%), M. minutus (50.0%), T. triton (50.0%), and R. norvegicus (25.0%). A total of 31,184 chigger mites collected from 508 rodents and insectivores were slide-mounted and 10 species belonging to 4 genera were identified. Leptotrombidium pallidum (53.4%) was the most frequently collected, followed by L. palpale (15.7%), Neotrombicula tamiyai (14.3%), L. orientale (10.7%), L. zetum (3.1%), Walchia fragilis (2.1%), and L. gemiticulum (0.8%), while the remaining 3 species, L. subintermedium, N. gardellai, and Euschoengastia koreaensis were rarely observed (prevalence < 10%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4), L. orientale (45.0), and L. palpale (21.4), were observed during the spring season.
Animals ; Antibodies, Bacterial/immunology ; Arachnid Vectors/classification/*microbiology ; Disease Reservoirs/classification/microbiology/*parasitology ; Humans ; Military Facilities ; Orientia tsutsugamushi/*immunology/isolation & purification ; Republic of Korea ; Rodentia/classification/*immunology/microbiology/*parasitology ; Scrub Typhus/microbiology/*transmission/*veterinary ; Seroepidemiologic Studies ; Trombiculidae/classification/*microbiology