Standardization of epidemiological surveillance of acute rheumatic fever

Acute rheumatic fever (ARF) is a multiorgan inflammatory disorder that results from the body’s autoimmune response to pharyngitis or a skin infection caused by Streptococcus pyogenes (Strep A). Acute rheumatic fever mainly affects those in low- and middle-income nations, as well as in indigenous populations in wealthy nations, where initial Strep A infections may go undetected. A single episode of ARF puts a person at increased risk of developing long-term cardiac damage known as rheumatic heart disease. We present case definitions for both definite and possible ARF, including initial and recurrent episodes, according to the 2015 Jones Criteria, and we discuss current tests available to aid in the diagnosis. We outline the considerations specific to ARF surveillance methodology, including discussion on where and how to conduct active or passive surveillance (eg, early childhood centers/schools, households, primary healthcare, administrative database review), participant eligibility, and the surveillance population. Additional considerations for ARF surveillance, including implications for secondary prophylaxis and follow-up, ARF registers, community engagement, and the impact of surveillance, are addressed. Finally, the core elements of case report forms for ARF, monitoring and audit requirements, quality control and assurance, and the ethics of conducting surveillance are discussed

Measurement of the adhesion between single melamine-formaldehyde resin microparticles and a flat fabric surface using AFM

An understanding of the adhesion of microparticles, particularly microcapsules, containing a functional component to a fabric surface is crucial to an effective application of this component to the fibre. Fabric surface is very rough; hence, direct measurement of the adhesion of single microparticles to surfaces with a roughness greater than the particle diameter is difficult. In the study reported here, cotton films were generated by dissolving cotton powder in an organic solvent and their properties including surface roughness, thickness, contact angle and purity were characterised. The adhesive forces between single melamineformaldehyde (MF) resin microparticles and a cotton film under ambient conditions with a relative humidity of above 40% were measured using atomic force microscopy; they are considered to be dominated by capillary forces. It was found that there was little adhesion between a MF microparticle and a cotton film in an aqueous solution of sodium dodecylbenzene sulphonate as surfactant. Repulsion between them was observed, but it reduced with increase in the surfactant concentration and decrease in the pH of the solution. The repulsion contributions are thought to originate mainly from electrostatic repulsion. It is believed that the studies on the adhesion between single MF microparticles and a cotton film under ambient conditions or dispersed in surfactant solutions, are beneficial to the attempts to enhance the adhesion of microcapsules to fabric surfaces via a modification of their surface composition and morphology

Standardization of epidemiological surveillance of rheumatic heart disease

Rheumatic heart disease (RHD) is a long-term sequela of acute rheumatic fever (ARF), which classically begins after an untreated or undertreated infection caused by Streptococcus pyogenes (Strep A). RHD develops after the heart valves are permanently damaged due to ARF. RHD remains a leading cause of morbidity and mortality in young adults in resource-limited and low- and middle-income countries. This article presents case definitions for latent, suspected, and clinical RHD for persons with and without a history of ARF, and details case classifications, including differentiating between definite or borderline according to the 2012 World Heart Federation echocardiographic diagnostic criteria. This article also covers considerations specific to RHD surveillance methodology, including discussions on echocardiographic screening, where and how to conduct active or passive surveillance (eg, early childhood centers/schools, households, primary healthcare), participant eligibility, and the surveillance population. Additional considerations for RHD surveillance, including implications for secondary prophylaxis and follow-up, RHD registers, community engagement, and the negative impact of surveillance, are addressed. Finally, the core elements of case report forms for RHD, monitoring and audit requirements, quality control and assurance, and the ethics of conducting surveillance are discussed

Aberrant Water Homeostasis Detected by Stable Isotope Analysis

While isotopes are frequently used as tracers in investigations of disease physiology (i.e., 14C labeled glucose), few studies have examined the impact that disease, and disease-related alterations in metabolism, may have on stable isotope ratios at natural abundance levels. The isotopic composition of body water is heavily influenced by water metabolism and dietary patterns and may provide a platform for disease detection. By utilizing a model of streptozotocin (STZ)-induced diabetes as an index case of aberrant water homeostasis, we demonstrate that untreated diabetes mellitus results in distinct combinations, or signatures, of the hydrogen (δ2H) and oxygen (δ18O) isotope ratios in body water. Additionally, we show that the δ2H and δ18O values of body water are correlated with increased water flux, suggesting altered blood osmolality, due to hyperglycemia, as the mechanism behind this correlation. Further, we present a mathematical model describing the impact of water flux on the isotopic composition of body water and compare model predicted values with actual values. These data highlight the importance of factors such as water flux and energy expenditure on predictive models of body water and additionally provide a framework for using naturally occurring stable isotope ratios to monitor diseases that impact water homeostasis

Shrinking wings for ultrasonic pitch production: hyperintense ultra-short-wavelength calls in a new genus of neotropical katydids (Orthoptera: tettigoniidae)

This article reports the discovery of a new genus and three species of predaceous katydid (Insecta: Orthoptera) from Colombia and Ecuador in which males produce the highest frequency ultrasonic calling songs so far recorded from an arthropod. Male katydids sing by rubbing their wings together to attract distant females. Their song frequencies usually range from audio (5 kHz) to low ultrasonic (30 kHz). However, males of Supersonus spp. call females at 115 kHz, 125 kHz, and 150 kHz. Exceeding the human hearing range (50 Hz–20 kHz) by an order of magnitude, these insects also emit their ultrasound at unusually elevated sound pressure levels (SPL). In all three species these calls exceed 110 dB SPL rms re 20 µPa (at 15 cm). Males of Supersonus spp. have unusually reduced forewings (<0.5 mm2). Only the right wing radiates appreciable sound, the left bears the file and does not show a particular resonance. In contrast to most katydids, males of Supersonus spp. position and move their wings during sound production so that the concave aspect of the right wing, underlain by the insect dorsum, forms a contained cavity with sharp resonance. The observed high SPL at extreme carrier frequencies can be explained by wing anatomy, a resonant cavity with a membrane, and cuticle deformation

High-performance work systems and innovation in Vietnamese small firms

This article examines the interplay between high-performance work systems (HPWS) and the innovation of Vietnamese small and medium-sized enterprises (SMEs). Our conceptual model relies on the componential theory of creativity along with HPWS, learning goal orientation (LGO), creativity and innovation to hypothesise both mediation and moderation mechanisms linking such a relationship. Using a sample of 133 SMEs, we find that (1) employee creativity mediates the pathway between HPWS and firm innovation; and (2) LGO moderates the HPWS - employee creativity relationship. Our study casts new light on the theoretical mechanism through which HPWS influence firm innovation and adds to understanding about HPWS within SMEs by bringing employees centre stage

In Vitro Thermal Effects on Embryonic Cells of Endangered Hawksbill Turtle Eretmochelys imbricata

The hawksbill turtle is an ectotherm, whose sex is determined by temperature during embryonic development. This study aimed to determine whether embryonic hawksbill turtle cells respond differently to temperature than mammalian cells. Embryonic hawksbill turtle cells were established in culture, and thermal effects on these cells were investigated in vitro. Cells were maintained in Dulbecco\u27s Modified Eagle Medium supplemented with non-essential amino acids, vitamin solution, sodium pyruvate, and 10% fetal bovine serum at 33°C and cell proliferation occurred at 25-33°C. When cells were incubated at 37°C (the temperature of mammalian cell culture) for 24 h, cell growth was completely inhibited. This growth inhibition was evidently recovered by changing the incubation temperature back to 33°C. Expression of heat shock protein was found to increase with elevating culture temperature from 25 to 33°C

Standardization of epidemiological surveillance of invasive Group A streptococcal infections

Invasive group A streptococcal (Strep A) infections occur when Streptococcus pyogenes, also known as beta-hemolytic group A Streptococcus, invades a normally sterile site in the body. This article provides guidelines for establishing surveillance for invasive Strep A infections. The primary objective of invasive Strep A surveillance is to monitor trends in rates of infection and determine the demographic and clinical characteristics of patients with laboratory-confirmed invasive Strep A infection, the age- and sex-specific incidence in the population of a defined geographic area, trends in risk factors, and the mortality rates and rates of nonfatal sequelae caused by invasive Strep A infections. This article includes clinical descriptions followed by case definitions, based on clinical and laboratory evidence, and case classifications (confirmed or probable, if applicable) for invasive Strep A infections and for 3 Strep A syndromes: streptococcal toxic shock syndrome, necrotizing fasciitis, and pregnancy-associated Strep A infection. Considerations of the type of surveillance are also presented, noting that most people who have invasive Strep A infections will present to hospital and that invasive Strep A is a notifiable disease in some countries. Minimal surveillance necessary for invasive Strep A infection is facility-based, passive surveillance. A resource-intensive but more informative approach is active case finding of laboratory-confirmed Strep A invasive infections among a large (eg, state-wide) and well defined population. Participant eligibility, surveillance population, and additional surveillance components such as the use of International Classification of Disease diagnosis codes, follow-up, period of surveillance, seasonality, and sample size are discussed. Finally, the core data elements to be collected on case report forms are presented

Living in the Past: Phylogeography and Population Histories of Indo-Pacific Wrasses (Genus Halichoeres) in Shallow Lagoons versus Outer Reef Slopes

Sea level fluctuations during glacial cycles affect the distribution of shallow marine biota, exposing the continental shelf on a global scale, and displacing coral reef habitat to steep slopes on oceanic islands. In these circumstances we expect that species inhabiting lagoons should show shallow genetic architecture relative to species inhabiting more stable outer reefs. Here we test this expectation on an ocean-basin scale with four wrasses (genus Halichoeres): H. claudia (N = 194, with ocean-wide distribution) and H. ornatissimus (N = 346, a Hawaiian endemic) inhabit seaward reef slopes, whereas H. trimaculatus (N = 239) and H. margaritaceus (N = 118) inhabit lagoons and shallow habitats throughout the Pacific. Two mitochondrial markers (cytochrome oxidase I and control region) were sequenced to resolve population structure and history of each species. Haplotype and nucleotide diversity were similar among all four species. The outer reef species showed significantly less population structure, consistent with longer pelagic larval durations. Mismatch distributions and significant negative Fu’s F values indicate Pleistocene population expansion for all species, and (contrary to expectations) shallower histories in the outer slope species. We conclude that lagoonal wrasses may persist through glacial habitat disruptions, but are restricted to refugia during lower sea level stands. In contrast, outer reef slope species have homogeneous and well-connected populations through their entire ranges regardless of sea level fluctuations. These findings contradict the hypothesis that shallow species are less genetically diverse as a consequence of glacial cycles

Adhesion Forces and Coaggregation between Vaginal Staphylococci and Lactobacilli

Urogenital infections are the most common ailments afflicting women. They are treated with dated antimicrobials whose efficacy is diminishing. The process of infection involves pathogen adhesion and displacement of indigenous Lactobacillus crispatus and Lactobacillus jensenii. An alternative therapeutic approach to antimicrobial therapy is to reestablish lactobacilli in this microbiome through probiotic administration. We hypothesized that lactobacilli displaying strong adhesion forces with pathogens would facilitate coaggregation between the two strains, ultimately explaining the elimination of pathogens seen in vivo. Using atomic force microscopy, we found that adhesion forces between lactobacilli and three virulent toxic shock syndrome toxin 1-producing Staphylococcus aureus strains, were significantly stronger (2.2–6.4 nN) than between staphylococcal pairs (2.2–3.4 nN), especially for the probiotic Lactobacillus reuteri RC-14 (4.0–6.4 nN) after 120 s of bond-strengthening. Moreover, stronger adhesion forces resulted in significantly larger coaggregates. Adhesion between the bacteria occurred instantly upon contact and matured within one to two minutes, demonstrating the potential for rapid anti-pathogen effects using a probiotic. Coaggregation is one of the recognized mechanisms through which lactobacilli can exert their probiotic effects to create a hostile micro-environment around a pathogen. With antimicrobial options fading, it therewith becomes increasingly important to identify lactobacilli that bind strongly with pathogens