Improving retention of community-recruited participants in HIV prevention research through Saturday household visits; findings from the HPTN 071 (PopART) study in South Africa.

BACKGROUND: Identifying successful strategies to improve participant retention in longitudinal studies remains a challenge. In this study we evaluated whether non-traditional fieldworker shifts (after hours during the week and weekends) enhanced participant retention when compared to retention during traditional weekday shifts in the HPTN 071 (PopART) population cohort (PC). METHODS: HPTN 071 (PopART) PC participants were recruited and followed up in their homes on an annual basis by research fieldworkers over a 3-4 year period. The average number of successful follow-up visits, where a PC participant was found and retained in the study, was calculated for each of 3 visit schedules (early weekday shift, late weekday shift, and Saturday shift), and standardized to account for variation in fieldwork shift duration. We used one-way univariate analysis of variance (ANOVA) to describe differences in mean-successful visits and 95% confidence intervals between the shift types. RESULTS: Data on 16 651 successful visits were included. Successful visit rates were higher when conducting Saturday visits (14.0; 95% CI: 11.3-16.6) compared to both regular (4.5; 95% CI: 3.7-5.3) and late weekday shifts (5.3; 95% CI: 4.7-5.8) overall and in all subgroup analyses (P<0.001). The successful visit rate was higher amongst women than men were during all shift types (3.2 vs. 1.3, p<0.001). Successful visit rates by shift type did not differ significantly by age, over time, by PC round or by community triplet. CONCLUSION: The number of people living with HIV continues to increase annually. High quality evidence from longitudinal studies remains critical for evaluating HIV prevention and treatment strategies. This study showed a significant benefit on participant retention through introduction of Saturday shifts for home visits and these data can make an important contribution to the emerging body of evidence for improving retention in longitudinal research. TRIAL REGISTRATION: PopART was approved by the Stellenbosch University Health Research Ethics Committees (N12/11/074), London School of Hygiene and Tropical Medicine (6326) ethics committee and the Division of AIDS (DAIDS) (Protocol ID 11865). PopART was registered with ClinicalTrials.gov (registration number NCT01900977 ).

Effect of acute exposure to high ambient temperature on the thermal, metabolic and hygric physiology of a small desert bird.

The intensity and frequency of extreme weather events, such as heat waves, are increasing as a consequence of global warming. Acute periods of extreme heat can be more problematic for wildlife than a chronic increase in mean temperature, to which animals can potentially acclimatise. Predicting effects of heat exposure requires a clear understanding of the capacity of individuals to respond to heat waves, so we examined the physiological response of a small desert bird, the zebra finch (Taeniopygia guttata), after acute previous exposure to high ambient temperature, simulating heatwave-like conditions. The standard physiology of the zebra finches was unaffected by prior exposure to heatwave-type conditions, suggesting that periodic exposure to heatwaves is unlikely to impact their longer-term day-to-day energy and water requirements. When finches were thermally challenged, prior experience of heatwave-like conditions did not impact overall body temperature and evaporative water loss, but birds previously experiencing high temperatures did reduce their metabolic heat production, and the variance in water loss and metabolism between individuals was significantly lower. This suggests that some individuals are more likely to become dehydrated if they have not had prior experience of high temperatures, and do not prioritise water conservation over thermoregulation. However, our observations overall suggest that acute periods of heat exposure do little to modify the general physiology of small birds, supporting the hypothesis that periodic extreme heat events may be more problematic for them than chronic warming.

Higher temperatures during development reduce body size in the zebra finch in the laboratory and in the wild.

The most commonly documented morphological response across many taxa to climatic variation across their range follows Bergmann's rule, which predicts larger body size in colder climates. In observational data from wild zebra finches breeding across a range of temperatures in the spring and summer, we show that this relationship appears to be driven by the negative effect of high temperatures during development. This idea was then experimentally tested on zebra finches breeding in temperature-controlled climates in the laboratory. These experiments confirmed that those individualso produced in a hot environment (30 °C) were smaller than those produced in cool conditions (18 °C). Our results suggest a proximate causal link between temperature and body size and suggest that a hotter climate during breeding periods could drive significant changes in morphology within and between populations. This effect could account for much of the variation in body size that drives the well-observed patterns first described by Bergmann and that is still largely attributed to selection on adult body size during cold winters. The climate-dependent developmental plasticity that we have demonstrated is an important component in understanding how endotherms may be affected by climate change.

The colour of paternity: extra-pair paternity in the wild Gouldian finch does not appear to be driven by genetic incompatibility between morphs.

In socially monogamous species, individuals can use extra-pair paternity and offspring sex allocation as adaptive strategies to ameliorate costs of genetic incompatibility with their partner. Previous studies on domesticated Gouldian finches (Erythrura gouldiae) demonstrated a genetic incompatibility between head colour morphs, the effects of which are more severe in female offspring. Domesticated females use differential sex allocation, and extra-pair paternity with males of compatible head colour, to reduce fitness costs associated with incompatibility in mixed-morph pairings. However, laboratory studies are an oversimplification of the complex ecological factors experienced in the wild and may only reflect the biology of a domesticated species. This study aimed to examine the patterns of parentage and sex ratio bias with respect to colour pairing combinations in a wild population of the Gouldian finch. We utilized a novel PCR assay that allowed us to genotype the morph of offspring before the morph phenotype develops and to explore bias in morph paternity and selection at the nest. Contrary to previous findings in the laboratory, we found no effect of pairing combinations on patterns of extra-pair paternity, offspring sex ratio or selection on morphs in nestlings. In the wild, the effect of morph incompatibility is likely much smaller, or absent, than was observed in the domesticated birds. Furthermore, the previously studied domesticated population is genetically differentiated from the wild population, consistent with the effects of domestication. It is possible that the domestication process fostered the emergence (or enhancement) of incompatibility between colour morphs previously demonstrated in the laboratory.

Linkage mapping of a polymorphic plumage locus associated with intermorph incompatibility in the Gouldian finch (Erythrura gouldiae).

Colour polymorphism is known to facilitate speciation but the genetic basis of animal pigmentation and how colour polymorphisms contribute to speciation is poorly understood. Restricted recombination may promote linkage disequilibrium between the colour locus and incompatibility genes. Genomic rearrangement and the position of relevant loci within a chromosome are important factors that influence the frequency of recombination. Therefore, it is important to know the position of the colour locus, gene order and recombination landscape of the chromosome to understand the mechanism that generates incompatibilities between morphs. Recent studies showed remarkable pre- and postzygotic incompatibilities between sympatric colour morphs of the Gouldian finch (Erythrura gouldiae), in which head feather colour is genetically determined by a single sex-linked locus, Red. We constructed a genetic map for the Z chromosome of the Gouldian finch (male-specific map distance=131 cM), using 618 captive-bred birds and 34 microsatellite markers, to investigate the extent of inter- and intraspecific genomic rearrangements and variation in recombination rate within the Z chromosome. We refined the location of the Red locus to a ~7.2-cM interval in a region with a moderate recombination rate but outside the least-recombining, putative centromeric region. There was no evidence of chromosome-wide genomic rearrangements between the chromosomes carrying the red or black alleles with the current marker resolution. This work will contribute to identifying the causal gene, which will in turn enable alternative explanations for the association between incompatibility and colouration, such as fine-scale linkage disequilibrium, genomic rearrangements and pleiotropy, to be tested.

Quantifying realized inbreeding in wild and captive animal populations.

Most molecular measures of inbreeding do not measure inbreeding at the scale that is most relevant for understanding inbreeding depression-namely the proportion of the genome that is identical-by-descent (IBD). The inbreeding coefficient FPed obtained from pedigrees is a valuable estimator of IBD, but pedigrees are not always available, and cannot capture inbreeding loops that reach back in time further than the pedigree. We here propose a molecular approach to quantify the realized proportion of the genome that is IBD (propIBD), and we apply this method to a wild and a captive population of zebra finches (Taeniopygia guttata). In each of 948 wild and 1057 captive individuals we analyzed available single-nucleotide polymorphism (SNP) data (260 SNPs) spread over four different genomic regions in each population. This allowed us to determine whether any of these four regions was completely homozygous within an individual, which indicates IBD with high confidence. In the highly nomadic wild population, we did not find a single case of IBD, implying that inbreeding must be extremely rare (propIBD=0-0.00094, 95% CI). In the captive population, a five-generation pedigree strongly underestimated the average amount of realized inbreeding (FPed=0.013

Types of female partners reported by black men who have sex with men and women (MSMW) and associations with intercourse frequency, unprotected sex and HIV and STI prevalence.

We used baseline data from a study of Black MSM/MSMW in 6 US cities to examine the association of female partnership types with disease prevalence and sexual behaviors among the 555 MSMW participants. MSMW reported more than three times as many total and unprotected sex acts with each primary as they did with each non-primary female partner. We compared MSMW whose recent female partners were: (1) all primary ("PF only", n = 156), (2) both primary and non-primary ("PF & NPF", n = 186), and (3) all non-primary ("NPF only", n = 213). HIV/STI prevalence did not differ significantly across groups but sexual behaviors did. The PF only group had the fewest male partners and was the most likely to have only primary male partners; the PF & NPF group was the most likely to have transgender partners. PF & NPF men reported the most sex acts (total and unprotected) with females; NPF only men reported the fewest. Implications for HIV risk and prevention are discussed.

Evaluating remote facilitation intensity for multi-national translation of nurse-initiated stroke protocols (QASC Australasia): a protocol for a cluster randomised controlled trial.

BACKGROUND: Facilitated implementation of nurse-initiated protocols to manage fever, hyperglycaemia (sugar) and swallowing difficulties (FeSS Protocols) in 19 Australian stroke units resulted in reduced death and dependency for stroke patients. However, a significant gap remains in translating this evidence-based care bundle protocol into standard practice in Australia and New Zealand. Facilitation is a key component for increasing implementation. However, its contribution to evidence translation initiatives requires further investigation. We aim to evaluate two levels of intensity of external remote facilitation as part of a multifaceted intervention to improve FeSS Protocol uptake and quality of care for patients with stroke in Australian and New Zealand acute care hospitals. METHODS: A three-arm cluster randomised controlled trial with a process evaluation and economic evaluation. Australian and New Zealand hospitals with a stroke unit or service will be recruited and randomised in blocks of five to one of the three study arms-high- or low-intensity external remote facilitation or a no facilitation control group-in a 2:2:1 ratio. The multicomponent implementation strategy will incorporate implementation science frameworks (Theoretical Domains Framework, Capability, Opportunity, Motivation - Behaviour Model and the Consolidated Framework for Implementation Research) and include an online education package, audit and feedback reports, local clinical champions, barrier and enabler assessments, action plans, reminders and external remote facilitation. The primary outcome is implementation effectiveness using a composite measure comprising six monitoring and treatment elements of the FeSS Protocols. Secondary outcome measures are as follows: composite outcome of adherence to each of the combined monitoring and treatment elements for (i) fever (n=5); (ii) hyperglycaemia (n=6); and (iii) swallowing protocols (n=7); adherence to the individual elements that make up each of these protocols; comparison for composite outcomes between (i) metropolitan and rural/remote hospitals; and (ii) stroke units and stroke services. A process evaluation will examine contextual factors influencing intervention uptake. An economic evaluation will describe cost differences relative to each intervention and study outcomes. DISCUSSION: We will generate new evidence on the most effective facilitation intensity to support implementation of nurse-initiated stroke protocols nationwide, reducing geographical barriers for those in rural and remote areas. TRIAL REGISTRATION: ACTRN12622000028707. Registered 14 January, 2022.

Kin selection, not group augmentation, predicts helping in an obligate cooperatively breeding bird.

Kin selection theory has been the central model for understanding the evolution of cooperative breeding, where non-breeders help bear the cost of rearing young. Recently, the dominance of this idea has been questioned; particularly in obligate cooperative breeders where breeding without help is uncommon and seldom successful. In such systems, the direct benefits gained through augmenting current group size have been hypothesized to provide a tractable alternative (or addition) to kin selection. However, clear empirical tests of the opposing predictions are lacking. Here, we provide convincing evidence to suggest that kin selection and not group augmentation accounts for decisions of whether, where and how often to help in an obligate cooperative breeder, the chestnut-crowned babbler (Pomatostomus ruficeps). We found no evidence that group members base helping decisions on the size of breeding units available in their social group, despite both correlational and experimental data showing substantial variation in the degree to which helpers affect productivity in units of different size. By contrast, 98 per cent of group members with kin present helped, 100 per cent directed their care towards the most related brood in the social group, and those rearing half/full-sibs helped approximately three times harder than those rearing less/non-related broods. We conclude that kin selection plays a central role in the maintenance of cooperative breeding in this species, despite the apparent importance of living in large groups.

Fecundity selection on ornamental plumage colour differs between ages and sexes and varies over small spatial scales.

Avian plumage colours are some of the most conspicuous sexual ornaments, and yet standardized selection gradients for plumage colour have rarely been quantified. We examined patterns of fecundity selection on plumage colour in blue tits (Cyanistes caeruleus L.). When not accounting for environmental heterogeneity, we detected relatively few cases of selection. We found significant disruptive selection on adult male crown colour and yearling female chest colour and marginally nonsignificant positive linear selection on adult female crown colour. We discovered no new significant selection gradients with canonical rotation of the matrix of nonlinear selection. Next, using a long-term data set, we identified territory-level environmental variables that predicted fecundity to determine whether these variables influenced patterns of plumage selection. The first of these variables, the density of oaks within 50 m of the nest, influenced selection gradients only for yearling males. The second variable, an inverse function of nesting density, interacted with a subset of plumage selection gradients for yearling males and adult females, although the strength and direction of selection did not vary predictably with population density across these analyses. Overall, fecundity selection on plumage colour in blue tits appeared rare and inconsistent among sexes and age classes.

Short- and long-term consequences of early developmental conditions: a case study on wild and domesticated zebra finches.

Divergent selection pressures among populations can result not only in significant differentiation in morphology, physiology and behaviour, but also in how these traits are related to each other, thereby driving the processes of local adaptation and speciation. In the Australian zebra finch, we investigated whether domesticated stock, bred in captivity over tens of generations, differ in their response to a life-history manipulation, compared to birds taken directly from the wild. In a 'common aviary' experiment, we thereto experimentally manipulated the environmental conditions experienced by nestlings early in life by means of a brood size manipulation, and subsequently assessed its short- and long-term consequences on growth, ornamentation, immune function and reproduction. As expected, we found that early environmental conditions had a marked effect on both short- and long-term morphological and life-history traits in all birds. However, although there were pronounced differences between wild and domesticated birds with respect to the absolute expression of many of these traits, which are indicative of the different selection pressures wild and domesticated birds were exposed to in the recent past, manipulated rearing conditions affected morphology and ornamentation of wild and domesticated finches in a very similar way. This suggests that despite significant differentiation between wild and domesticated birds, selection has not altered the relationships among traits. Thus, life-history strategies and investment trade-offs may be relatively stable and not easily altered by selection. This is a reassuring finding in the light of the widespread use of domesticated birds in studies of life-history evolution and sexual selection, and suggests that adaptive explanations may be legitimate when referring to captive bird studies.

Epigenetic and genetic variation among three separate introductions of the house sparrow (Passer domesticus) into Australia.

Invasive populations are often associated with low levels of genetic diversity owing to population bottlenecks at the initial stages of invasion. Despite this, the ability of invasive species to adapt rapidly in response to novel environments is well documented. Epigenetic mechanisms have recently been proposed to facilitate the success of invasive species by compensating for reduced levels of genetic variation. Here, we use methylation sensitive-amplification fragment length polymorphism and microsatellite analyses to compare levels of epigenetic and genetic diversity and differentiation across 15 sites in the introduced Australian house sparrow population. We find patterns of epigenetic and genetic differentiation that are consistent with historical descriptions of three distinct, introductions events. However unlike genetic differentiation, epigenetic differentiation was higher among sample sites than among invasion clusters, suggesting that patterns of epigenetic variation are more strongly influenced by local environmental stimuli or sequential founder events than the initial diversity in the introduction population. Interestingly, we fail to detect correlations between pairwise site comparisons of epigenetic and genetic differentiation, suggesting that some of the observed epigenetic variation has arisen independently of genetic variation. We also fail to detect the potentially compensatory relationship between epigenetic and genetic diversity that has been detected in a more recent house sparrow invasion in Africa. We discuss the potential for this relationship to be obscured by recovered genetic diversity in more established populations, and highlight the importance of incorporating introduction history into population-wide epigenetic analyses.

Idiopathic gastroparesis is associated with specific transcriptional changes in the gastric muscularis externa.

BACKGROUND: The molecular changes that occur in the stomach that are associated with idiopathic gastroparesis are poorly described. The aim of this study was to use quantitative analysis of mRNA expression to identify changes in mRNAs encoding proteins required for the normal motility functions of the stomach. METHODS: Full-thickness stomach biopsy samples were collected from non-diabetic control subjects who exhibited no symptoms of gastroparesis and from patients with idiopathic gastroparesis. mRNA was isolated from the muscularis externa and mRNA expression levels were determined by quantitative reverse transcriptase (RT)-PCR. KEY RESULTS: Smooth muscle tissue from idiopathic gastroparesis patients had decreased expression of mRNAs encoding several contractile proteins, such as MYH11 and MYLK1. Conversely, there was no significant change in mRNAs characteristic of interstitial cells of Cajal (ICCs) such as KIT or ANO1. There was also a significant decrease in mRNA-encoding platelet-derived growth factor receptor α (PDGFRα) and its ligand PDGFB and in Heme oxygenase 1 in idiopathic gastroparesis subjects. In contrast, there was a small increase in mRNA characteristic of neurons. Although there was not an overall change in KIT expression in gastroparesis patients, KIT expression showed a significant correlation with gastric emptying whereas changes in MYLK1, ANO1 and PDGFRα showed weak correlations to the fullness/satiety subscore of patient assessment of upper gastrointestinal disorder-symptom severity index scores. CONCLUSIONS AND INFERENCES: Our findings suggest that idiopathic gastroparesis is associated with altered smooth muscle cell contractile protein expression and loss of PDGFRα+ cells without a significant change in ICCs.

Does testosterone mediate the trade-off between nestling begging and growth in the canary (Serinus canaria)?

Nestling birds solicit food from their parents with vigorous begging displays, involving posturing, jostling and calling. In some species, such as canaries, begging is especially costly because it causes a trade off against nestling growth. Fitness costs of begging like this are predicted by evolutionary theory because they function to resolve conflicts of interest within the family over the provision of parental investment. However, the mechanism that links these costs with nestling behaviour remains unclear. In the present study, we determine if the relationships between nestling androgen levels, nestling begging intensities and nestling growth rates are consistent with the hypothesis that testosterone is responsible for the trade-off between begging and growth. We test this idea with a correlational study, using fecal androgens as a non-invasive method for assaying nestling androgen levels. Our results show that fecal androgen levels are positively correlated with nestling begging intensity, and reveal marked family differences in each trait. Furthermore, changes in fecal androgen levels between 5 and 8 days after hatching are positively associated with changes in nestling begging intensity, and negatively associated with nestling growth during this time. Although these correlational results support our predictions, we suggest that that experimental manipulations are now required to test the direct or indirect role of testosterone in mediating the trade-off between begging and growth.

Crystal structure of a protein repair methyltransferase from Pyrococcus furiosus with its L-isoaspartyl peptide substrate.

Protein L-isoaspartyl (D-aspartyl) methyltransferases (EC 2.1.1.77) are found in almost all organisms. These enzymes catalyze the S-adenosylmethionine (AdoMet)-dependent methylation of isomerized and racemized aspartyl residues in age-damaged proteins as part of an essential protein repair process. Here, we report crystal structures of the repair methyltransferase at resolutions up to 1.2 A from the hyperthermophilic archaeon Pyrococcus furiosus. Refined structures include binary complexes with the active cofactor AdoMet, its reaction product S-adenosylhomocysteine (AdoHcy), and adenosine. The enzyme places the methyl-donating cofactor in a deep, electrostatically negative pocket that is shielded from solvent. Across the multiple crystal structures visualized, the presence or absence of the methyl group on the cofactor correlates with a significant conformational change in the enzyme in a loop bordering the active site, suggesting a role for motion in catalysis or cofactor exchange. We also report the structure of a ternary complex of the enzyme with adenosine and the methyl-accepting polypeptide substrate VYP(L-isoAsp)HA at 2.1 A. The substrate binds in a narrow active site cleft with three of its residues in an extended conformation, suggesting that damaged proteins may be locally denatured during the repair process in cells. Manual and computer-based docking studies on different isomers help explain how the enzyme uses steric effects to make the critical distinction between normal L-aspartyl and age-damaged L-isoaspartyl and D-aspartyl residues.

A trade-off between reproduction and a condition-dependent sexually selected ornament in the house sparrow Passer domesticus.

Reproductive effort was manipulated in a free-living population of house sparrows (Passer domesticus) to investigate the trade-off between reproductive investment and the expression of a condition-dependent sexually selected ornament. Phenotypic plasticity in the expression of this trait was related to the experimentally manipulated size of the brood reared by a male. Males that invested more in current reproduction subsequently became more attractive to females in this population as they showed a preference for males with smaller badges. This supports the argument that direct benefits are a primary focus for mate choice by females. Trade-offs between reproductive effort and the expression of sexual ornaments are a potentially important source of phenotypic variation in both sexual ornaments and life-history traits.

Water intoxication associated with nephrogenic diabetes insipidus secondary to lithium: case report.

In the psychiatric population, psychogenic polydipsia leading to water intoxication and nephrogenic diabetes insipidus secondary to lithium therapy are both well-recognized entities. A case is reported of the apparently unusual combination of these two conditions, where lithium probably not only has caused the nephrogenic diabetes insipidus, but might also have contributed to the state of psychogenic polydipsia.

Experimental gallstone dissolution with methyl-tert-butyl ether (MTBE) and transcutaneous ultrasound energy.

The simultaneous application of ultrasound energy greatly accelerated the rate of cholesterol gallstone dissolution by methyl-tert-butyl ether (MTBE). In vitro experiments using this treatment showed that a 498-mg stone burden could be dissolved in 19.5 minutes, approximately 100% faster than what could be achieved with MTBE alone. Pigs (n = 13) with surgically implanted gallstones were treated with MTBE and transcutaneously applied ultrasound from a prototype system built for clinical studies. The average stone reduction of all pigs was 470.46 mg +/- 60.44 mg; 91.39% of an average implanted burden of 515.08 +/- 18.03 mg. Control group pigs (n = 9), receiving only an MTBE infusion, showed an average stone reduction of 51.77%. Enzymes indicative of hepatocellular injury showed no significant abnormalities after 6 weeks. Gallbladder ablation with a fibrous remnant (ie, no mucosa, no lumen, patent cystic duct) occurred in 10 (70%) of the pigs.

A large animal model (swine) to study the diagnosis and treatment of cholelithiasis.

Human gallstones were surgically placed into the gallbladders of 200 swine. Eight of these swine were used as a prospective series to verify that the placement and presence of human gallstones in their gallbladders caused no significant pathologic changes in the gallbladder and that the gallstones were not spontaneously dissolved. Although limitations exist, the advantages of this procedure demonstrate that the surgically prepared swine is an appropriate model for controlled in vivo experiments in radiologic imaging or interventional treatment. A 4 F pig-tailed catheter designed for Trocar insertion was developed as a companion to this model.

Extracorporeal liver ablation using sonography-guided high-intensity focused ultrasound.

RATIONALE AND OBJECTIVES: High-intensity focused ultrasound (HIFU) is the only radiation beam that can remotely destroy deep-seated tissue targets without causing damage to the intervening tissues. This study evaluates the ability of sonography-guided HIFU to extracorporeally induce liver ablation in a rabbit model. METHODS: Under sonographic guidance, the HIFU beam was transcutaneously focused at the target tissue in the liver through a subcostal approach. A computer controlled the HIFU exposure and transducer movement to destroy a preselected tissue volume. Simultaneous sonography monitored the tissue response. Ten insonated rabbits were killed from days 0 to 10, and the liver and intervening tissues were examined histologically. RESULTS: A sharply demarcated sonolesion of coagulation necrosis was produced in the liver in 9 of 10 animals. No damage was found in the intervening tissues (n = 6) when adequate acoustic coupling and proper beam path was applied. CONCLUSION: Sonography-guided HIFU might be a potential new modality for extracorporeal inducement of liver cancer ablation without resorting to laparatomy.