Early diagnosis of typhoid fever by the detection of salivary IgA

BACKGROUND:/AIMS: Current diagnostic methods for typhoid fever have low sensitivity and specificity. This study aimed to develop an enzyme linked immunosorbent assay (ELISA) with greater sensitivity and specificity. METHODS: The ELISA was developed and evaluated on patients with acute typhoid infection, febrile controls, and healthy controls. A sequential study on patients with culture confirmed typhoid was also carried out to determine the time period of maximum sensitivity. RESULTS: The ELISA detected anti-Salmonella typhi lipopolysaccharide (LPS) salivary IgA antibodies. A six month follow up study of patients with culture confirmed typhoid fever showed that the test shows maximum efficiency during the second and third weeks of fever and enables detection of the acute infection during the early phase. CONCLUSIONS: This ELISA can detect typhoid fever during the early phase of infection and is most efficient during the second and third weeks of fever, the time at which patients normally present for treatment. Because the sensitivity of the assay is subsequently greatly reduced, it will be useful for the diagnosis of acute infection.     

Method to estimate relative transmission efficiencies of Anopheles species (Diptera: Culicidae) in human malaria transmission.

A mathematical expression was derived to estimate the relative malaria transmission efficiency of an anopheline species with respect to a standard well-characterized species for which all vector parameters can be sufficiently determined. The method is particularly useful in situations where multiple anopheline species contribute to human malaria transmission and requires the estimation of the man-biting rate, the sporozoite rate, and the human malaria incidence. Under stable conditions of vector abundance, the average sporozoite rate in a species during a transmission season would by itself reflect its relative transmission efficiency. This "efficiency" then was used to calculate the "effective human-biting rate"; i.e., the human-biting rate of that species if it were to have ecological properties identical to those of the standard species. The standard well-characterized species then could be used with the effective human-biting rate of all species to quantify transmission, thus overcoming the need to measure vector parameters for all anopheline species contributing to transmission. An expression also was derived to calculate the relative contribution made by each species to malaria transmission. The usefulness of this method was illustrated using entomological and epidemiological data from Kataragama, Sri Lanka.     

Epidemiology of Chronic Kidney Disease,With Special Emphasis on Chronic Kidney Disease of Uncertain Etiology,in the North Central Region of Sri Lanka

Background

The aim of the study was to identify the epidemiology of chronic kidney disease of uncertain etiology in Sri Lanka.

Methods

A cross-sectional study was carried out by analyzing health statistics, and three cohort studies were conducted (n = 15 630, 3996, and 2809) to analyze the demographic information, age-specific prevalence, etiology, and stage of presentation. We screened 7604 individuals for chronic kidney disease of uncertain etiology.

Results

The results showed that the male:female ratio was 2.4:1, the mean age of patients was 54.7 ± 8 years, 92% of the patients were farmers, and 93% consumed water from shallow dug wells. Familial occurrence was common (36%). The prevalence of chronic kidney disease in different age groups was 3% in those aged 30–40 years; 7% in those aged 41–50 years, 20% in those aged 51–60 years, and 29% in those older than 60 years. Chronic kidney disease of uncertain etiology was diagnosed in 70.2% of patients, while 15.7% and 9.6% were due to hypertension and diabetic mellitus, respectively. The majority of patients were stage 4 (40%) at first presentation, while 31.8% were stage 3 and 24.5% were stage 5. Stage 1 and 2 presentation accounted for only 3.4%.

Conclusions

Low prevalence of CKDU was noticed (1.5%) among those who consumed water from natural springs. Prevalence was highest among males, rice farming communities, and those presenting at later disease stages.Key words: chronic kidney disease, uncertain etiology, epidemiology, North Central Province, male farmers, natural spring water     

Anxiety disorders are associated with verbal memory impairment in patients with Parkinson’s disease without dementia

Journal of Neurology - Preliminary evidence has demonstrated a link between anxiety and memory impairment in Parkinson’s disease (PD). This study further investigated this association using...     

Arginase activity mediates reversible T cell hyporesponsiveness in human pregnancy

Complex regulation of T cell functions during pregnancy is required to ensure materno-fetal tolerance. Here we reveal a novel pathway for the temporary suppression of maternal T cell responses in uncomplicated human pregnancies. Our results show that arginase activity is significantly increased in the peripheral blood of pregnant women and remarkably high arginase activities are expressed in term placentae. High enzymatic activity results in high turnover of its substrate L-arginine and concomitant reduction of this amino acid in the microenvironment. Amino acid deprivation is emerging as a regulatory pathway of lymphocyte responses and we assessed the consequences of this enhanced arginase activity on T cell responses. Arginase-mediated L-arginine depletion induces down-regulation of CD3 zeta, the main signalling chain of the TCR, and functional T cell hyporesponsiveness. Importantly, this arginase-mediated T cell suppression was reversible, as inhibition of arginase activity or addition of exogenous L-arginine restored CD3 zeta chain expression and T cell proliferation. Thus, L-arginine metabolism constitutes a novel physiological mechanism contributing to the temporary suppression of the maternal immune response during human pregnancy.     

The impact of COVID-19 on the provision of cardiac surgical services

The global pandemic caused by COVID-19 has had a significant global impact on healthcare systems. One implication of this pandemic is the cancellation of elective cardiac surgeries and the centralization of services. As a result, hospitals in Europe, North America, and the United Kingdom have had to alter the services offered to patients to be able to cope with service provision for COVID infected patients. Data should be collected during this period to provide a good insight following the lockdown period to understand the implication of such service alteration. Future research should also focus on the effects on long-term mortality and morbidity as well as financial implications on hospitals as a result of these changes.