Evaluation of Etest strips for rapid susceptibility testing of Mycobacterium tuberculosis

In this study, our objective was to evaluate Etest strips containing exponential gradients of isoniazid (INH), rifampin (RIF), and streptomycin (STR) for susceptibility testing of Mycobacterium tuberculosis. M. tuberculosis isolates were tested for antimicrobial susceptibilities by the standard proportion method using L?wenstein-Jensen (LJ) medium and by the Etest. The MICs determined by the Etest were obtained at 5, 7, or 10 days. In some strains with Etest-discrepant results, radiometric susceptibility testing (BACTEC) was performed to determine a consensus result. M. tuberculosis concordance between the two methods was 97% (86 of 89 isolates) for RIF, 96% for INH (84 of 87 isolates), and 80% (61 of 76 isolates) for STR. Most of the MICs determined by the Etest were easy to interpret and readable within 5 days. Results correlated well with those obtained by the LJ proportion and BACTEC methods for INH and RIF. However, a high proportion of false-sensitive and false-resistant results were observed, most often for STR. We also observed that variations in the inoculum size of M. tuberculosis isolates affected the MICs to a substantial degree. These discrepancies, along with the expense of the media, the Etest strips, and the specialized equipment required (CO2 incubator), make this method less useful in developing countries.     

Firing of inferior colliculus neurons in response to low-frequency sound stimulation during sleep and waking

SUMMARY  In vivo extracellular recordings of 102 units in the central nucleus of the inferior colliculus (IC), were made in chronically implanted guinea-pigs during the sleep/wake cycle. During wakefulness, the units were classified according to their response characteristics. Most neurons (63%) recorded showed changes, increasing or decreasing in the number of evoked discharges during the animal's transitions between wakefulness and slow-wave sleep. In the paradoxical sleep phase, the result was similar; changes were observed in most neurons, while only 11% of units did not shift their discharge pattern during ipsilateral sound stimulation.
The post-stimulus time histogram of the overall evoked pattern of discharge showed sleep/wake dependency, i.e. changed in 35% of the units recorded during the 50 ms of sound stimulation.
Fifty-five percent of auditory neurons did not show any change in the spontaneous firing rate during slow-wave sleep as compared to the previous waking period, while 22% exhibited a discharge increase and 23% decreased their firing. During paradoxical sleep, 14 out of 17 cells increased their spontaneous firing rate. The IC auditory neurons send descending connections to regions such as the dorsal pontine nuclei, known to mediate sleep processes. Thus, for constant auditory input, the firing rate or number of discharge variations are due to functional shifts in the sleeping brain. Auditory processing is present during sleep and differs from that observed during wakefulness. Differences were observed in the evoked firing number and/or spontaneous rate, as well as in the pattern of discharge. The ultimate reason for auditory unit shifts during sleep remains yet unexplained.     

Nitric oxide mediates the inhibition of neutrophil migration induced by systemic administration of LPS

To investigate the role of NO in the inhibition of neutrophil migration by circulating endotoxin, mice were pretreated with NO synthase inhibitors or with a free radical scavenger (D-penicillamine), before intravenous LPS injection. LPS dose-dependently inhibited the thioglycollate-induced neutrophil migration into the peritoneal cavities. Aminoguanidine, a selective inducible NO synthase inhibitor, abolished the inhibition of neutrophil migration and the increase in serum nitrate levels induced by a nonlethal dose of LPS. During lethal endotoxemia aminoguanidine partially abolished the neutrophil migration inhibition. Additionally, D-penicillamine prevented the inhibition of neutrophil migration caused by LPS. However, Nitro-L-Arginine, a selective constitutive NO synthase inhibitor, did not prevent neutrophil migration inhibition. Aminoguanidine treatment did not affect the systemic increased levels of TNF-, IL-1, and IL-10, suggesting that NO is the final mediator involved in the inhibition of neutrophil migration. Our results suggest that NO released by the inducible NO synthase mediates the inhibition of neutrophil migration mediated by circulating LPS.     

Immunoglobulin G and immunoglobulin M enzyme-linked immunosorbent assays and defined toxoplasmosis serological patterns.

Enzyme-linked immunosorbent assay (ELISA) for toxoplasmosis was evaluated in serum samples presenting defined toxoplasmosis serological patterns, as determined by results in immunoglobulin (Ig)G and IgM immunofluorescence (IgG-IF, IgM-IF), hemagglutination, and complement fixation tests. ELISA was carried out with alkaline phosphatase-labeled anti-IgG and anti-IgM antibodies. Serum titer was expressed as the serum dilution end point determined by mere observation of color development in the test. A straight agreement was found between IgG-ELISA and IgG-IF titers, both in group A sera of ancient infections (patterns II and III) and group B sera of recent infections (pattern I). A similar agreement was found between IgG-ELISA and hemagglutination titers in group A sera, for which coincident IgG-IF and hemagglutination titers are also frequent. However, in group B sera, in spite of the same toxoplasma extract being used to sensitize both plastic surfaces and erythrocytes, IgG-ELISA titers were much higher than hemagglutination titers, in a way similar to that observed for IgG-IF titers. IgM-ELISA was positive in every group B serum, with higher titers than corresponding IgM-IF titers. Occasional low-titered positive IgM-ELISA results were seen for group A sera, sometimes due to IgM-antiglobulin antibodies. An easy test to perform, ELISA seems to be an adequate substitute for toxoplasmosis IF tests for routine purposes.     

RPGRIP1s with distinct neuronal localization and biochemical properties associate selectively with RanBP2 in amacrine neurons

RPGR and RPGRIP1 are molecular partners with vital roles in retinal function. Mutations in RPGR are implicated in heterogeneous retinal phenotypes, while those in RPGRIP1 lead to Leber congenital amaurosis. RPGR and RPGRIP1s differentially localize in photoreceptors among species. This may contribute to phenotype disparities among species bearing mutations in RPGR. However, it cannot account for the phenotype heterogeneity associated with RPGR- and RPGRIP1-linked mutations in the human. The existence of RPGRIP1 isoforms with distinct cellular, subcellular localizations and biochemical properties in the retina is shown. High mass RPGRIP1 isoforms, p175/p150, enriched in the outer segment (OS) compartment of photoreceptors are identified. The remaining isoforms are present across subcellular fractions, including nuclei and are soluble. The p175/p150 are predominantly sequestered in the cytoskeleton-insoluble fraction of OS and nuclei. In selective amacrine cells, and in the transformed photoreceptor line, 661W, RPGRIP1s localize at restricted foci to nuclear pore complexes and/or the vicinity of these. Among the nucleoporins, RPGRIP1 isoforms selectively associate in vivo with RanBP2 (Nup358). RPGRIP1s also decorate microtubules in 661W cells and occasionally form coiled-like inclusion bodies in the perikarya. These results support distinct but complementary functions of RPGRIP1 isoforms in cytoskeletal-mediated processes in photoreceptors and amacrine neurons, and may explain the Leber phenotype linked to RPGRIP1 mutations in humans. Moreover, the data implicate a role of RanBP2 in the pathogenesis of neuro(retino)pathies and as a docking station to mediate the nucleocytoplasmic shuttling of RPGRIP1s and their interaction with other partners in amacrine and 661W neurons.     

The use of volunteers in mass screening for high blood pressure

This paper describes the effectiveness of an incentive-based approach to screening for hypertension by comparing it to two more typical on-site screenings. In the "bounty system," adolescents were trained and certified in blood pressure assessment to enable them to conduct door-to-door blood pressure screenings. The youths received incentives for various phases of their training and the screenings. The two other screenings were conducted in a worksite and a public "community" setting. It was evident that incentives played a major role in recruiting adolescents to volunteer as screeners. The final results, however, revealed that this contact did not result in an increase in the number of persons screened as had been predicted. This was due in part to the reluctance of residents to admit teenagers into their homes and related problems.     

Dietary Patterns During Pregnancy and Their Association with Gestational Weight Gain and Anthropometric Measurements at Birth

Maternal and Child Health Journal - Dietary patterns can influence maternal and child health outcomes. The study aims to characterize dietary patterns during pregnancy as well as to identify their...     

Analytical Assessment and Nutritional Adequacy of School Lunches in Sintra’s Public Primary Schools

School meals present several cost benefits overtime at the short, medium, and long term for individuals and society. This cross-sectional study aims to analyse the nutritional composition and evaluate the adequacy of school lunches. One hundred and fifty-eight samples were collected and analysed from 10 primary schools in Sintra’s municipality, served during one week. On average, energy (27.7% daily energetic requirements) and carbohydrate (48.1%) contents did not reach the reference values, and the content of protein (19.5%) exceeded the reference value (p < 0.05). The mean total fat (28.8%) and saturated fatty acids (5.4%) content complied with the recommendations. The mean salt (1.7 g) and dietary fibre (8.3 g) content exceeded the reference value but did not differ significantly from the recommendations. Addressing school canteens is crucial, not only in a nutritional approach, but also as an opportunity to achieve healthier, sustainable, and accessible food systems, aligned with the Sustainable Development Goals 2030. We highlighted the importance of evaluating evidence-based practices and disseminated practice-based evidence regarding the adequacy of school lunches.     

Persistent human papillomavirus infection as a predictor of cervical intraepithelial neoplasia.

CONTEXT: Human papillomavirus (HPV) infection is believed to be the central cause of cervical cancer, although most of the epidemiological evidence has come from retrospective, case-control studies, which do not provide information on the dynamics of cumulative or persistent exposure to HPV infection. OBJECTIVE: To assess the risks of cervical neoplasia related to prior persistent HPV infections. DESIGN AND SETTING: Longitudinal study of the natural history of HPV infection and cervical neoplasia in women residing in the city of S?o Paulo, Brazil, which was conducted between November 1993 and March 1997 and involved repeated measurements of HPV and lesions with follow-up until June 2000. PARTICIPANTS: A total of 1611 women with no cytological lesions at enrollment and HPV test results available from the first 2 visits. MAIN OUTCOME MEASURE: Cervical specimens taken for Papanicolaou cytology and HPV testing every 4 months in the first year and twice yearly thereafter. Incident cervical cancer precursor lesions ascertained by expert review of all cytology smears. RESULTS: The incidence rate of squamous intraepithelial lesions (SILs) was 0.73 per 1000 women-months (95% confidence interval [CI], 0.5-0.9) among women free of HPV at the 2 initial visits and 8.68 (95% CI, 2.3-15.1) among women with HPV type 16 or 18 infections persisting over both visits. Relative to those negative for HPV oncogenic types at both initial visits, the relative risk (RR) of incident SIL was 10.19 (95% CI, 5.9-17.6) for persistent infections with any known oncogenic HPV types. The equivalent RR of incident high-grade SIL was 11.67 (95% CI, 4.1-33.3). The RRs of lesions were considerably higher for persistent infections with HPV type 16 or 18. CONCLUSION: A strong relationship exists between persistent HPV infections and SIL incidence, particularly for HPV types 16 and 18.