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Merino sheep are a breed of choice across the world, popularly kept for their wool and mutton value. They are often reared as a pure breed or used in crossbreeding and are a common component in synthetic breed development. This study evaluated genetic diversity, population structure, and breed divergence in 279 animals of Merino and Merino-based sheep breeds in South Africa using the Illumina Ovine SNP 50K BeadChip. The sheep breeds analysed included the three Merino-derived breeds of Dohne Merino (n = 50); Meatmaster (n = 47); and Afrino (n = 52) and five presumed ancestral populations of Merinos (Merino (n = 46); South African Merino (n = 10); and South African Mutton Merino (n = 8)); and the non-Merino founding breeds of Damara (n = 20); Ronderib Afrikaner (n = 17); and Nguni (n = 29). Highest genetic diversity values were observed in the Dohne Merino (DM), with H o = 0.39 ± 0.01, followed by the Meatmaster and South African Merino (SAM), with H o = 0.37 ± 0.03. The level of inbreeding ranged from 0.0 ± 0.02 (DM) to 0.27 ± 0.05 (Nguni). Analysis of molecular variance (AMOVA) showed high within-population variance (>80%) across all population categories. The first principal component (PC1) separated the Merino, South African Mutton Merino (SAMM), DM, and Afrino (AFR) from the Meatmaster, Damara, Nguni, and Ronderib Afrikaner (RDA). PC2 aligned each Merino-derived breed with its presumed ancestors and separated the SAMM from the Merino and SAM. The iHS analysis yielded selection sweeps across the AFR (12 sweeps), Meatmaster (four sweeps), and DM (29 sweeps). Hair/wool trait genes such as FGF12; metabolic genes of ICA1, NXPH1, and GPR171; and immune response genes of IL22, IL26, IFNAR1, and IL10RB were reported. Other genes include HMGA, which was observed as selection signatures in other populations; WNT5A, important in the development of the skeleton and mammary glands; ANTXR2, associated with adaptation to variation in climatic conditions; and BMP2, which has been reported as strongly selected in both fat-tailed and thin-tailed sheep. The DM vs. SAMM shared all six sweep regions on chromosomes 1, 10, and 11 with AFR vs. SAMM. Genes such as FGF12 on OAR 1:191.3-194.7 Mb and MAP2K4 on OAR 11:28.6-31.3 Mb were observed. The selection sweep on chromosome 10 region 28.6-30.3 Mb harbouring the RXFP2 for polledness was shared between the DM vs. Merino, the Meatmaster vs. Merino, and the Meatmaster vs. Nguni. The DM vs. Merino and the Meatmaster vs. Merino also shared an Rsb-based selection sweep on chromosome 1 region 268.5-269.9 Mb associated with the Calpain gene, CAPN7. The study demonstrated some genetic similarities between the Merino and Merino-derived breeds emanating from common founding populations and some divergence driven by breed-specific selection goals. Overall, information regarding the evolution of these composite breeds from their founding population will guide future breed improvement programs and management and conservation efforts.

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BACKGROUND: Breast cancer is recognised as a heterogeneous disorder, comprising a number of subcategories of several cellular compositions, molecular alterations as well as clinical behaviour. Across the world, research has been able to show that the most common molecular subtype is luminal A, followed by triple negative and human epidermal receptor 2 (HER2)-positive (non-luminal) subtype. However, another study found that the most common molecular subtype was HER2/neu amplification, suggesting that subtypes case frequencies differ in different people. OBJECTIVES: To determine the case frequency of molecular subtypes of breast cancers and the associated clinicopathological features in women from Limpopo Province, South Africa. METHOD: We performed a retrospective, cross-sectional descriptive study from July 2021 - June 2021 at Mankweng Hospital breast oncology clinic. The inclusion criterion was all women with histologically confirmed breast cancer. RESULT: We identified 222 women who met the inclusion criteria, and the age range (median) was 25 - 91 (54.8) years. The majority of the women came from the Vhembe district (28%; n=62), followed by Capricorn district (26%; n=59), Mopani district (17%; n=38), Sekhukhune district (16%; n=35), and Waterberg district (13%; n=28). Histology revealed that the most common type was invasive ductal carcinoma (no special type; 91.44%; n=203), followed by invasive mucinous carcinoma (4%; n=9). The most predominant molecular subtype was luminal B (48.19%; n=107), followed by luminal A (22.97%; n=51), triple negative (17.12%; n=38) and 11.75% (n=26) overexpressed HER2. More than one-third of the cancers were HER2-positive (40.54%; n=90), and 59.46% (n=132) were HER2-negative. The majority of patients presented with late-stage cancer (62.16%; n=138), and the rest presented with early-stage (I and II) disease (37.84%; n=84). CONCLUSION: The majority of our patients had luminal subtypes and hormonal receptor-positive breast cancers, which should be associated with very good clinical outcomes. However, the majority of patients presented late with advanced-stage disease and high Ki-67 expression. Therefore, research is required to help us understand why in our context patients present late with advanced-stage disease.

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BACKGROUND: The intersection of violence exposure and mental health problems is a public health crisis for South African (SA) adolescents. Understanding the impact of community violence on adolescent mental health can inform future interventions. OBJECTIVES: To assess pathways between community violence exposure and internalising and externalising problems in SA adolescents receiving mental healthcare, and the roles of parent and peer relationships in these associations. METHODS: Participants (N=120 parent-adolescent pairs) were recruited from four mental health clinics in Western Cape Province to participate in a pilot test of a family-based HIV prevention study. Adolescents reported on their exposure to community violence, parental attachment, peer support of risk behaviour, and mental health. Parents reported on adolescents' internalising and externalising mental health problems. Participants received transport money (ZAR30 = USD3) and a shopping voucher or cash (ZAR50 = USD5) for their time. RESULTS: Adolescents were 12 - 18 years old (mean (standard deviation) 14.39 (1.82) years), 53% were male, and 67% and 33% reported black African and mixed-race ethnicity, respectively. Parents were 94% female and reported an average monthly income of ZAR3 973 (USD397). Boys reported significantly higher rates of witnessing community violence than girls. Among boys, significant paths emerged from community violence and low parent attachment to externalising symptoms and from community violence to peer support of risky behaviour. For girls, the only significant path was from low parent attachment to peer support of risky behaviour. CONCLUSIONS: This cross-sectional study sheds new light on the possible pathways from witnessing community violence to mental health problems among SA adolescents. Identifying factors that drive and mitigate psychological distress in the context of persistent community violence is critical to SA's future and can inform the selection and delivery of appropriate and targeted evidence-based interventions.

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BACKGROUND: In South Africa, there are limited nationally representative data on the prevalence and factors associated with psychological distress. This study used a 2012 nationally representative population-based household survey to investigate factors associated with psychological distress in South Africa. METHODS: The survey is based on a multistage stratified cross-sectional design. Univariate and multivariate logistic regression models were fitted to identify factors associated with psychological distress. RESULTS: Out of a total 25860 participants, 23.9% reported psychological distress. Higher likelihood of reporting psychological distress was significantly associated with being female [OR = 1.68 (95% CI: 1.34-2.10), p < 0.001], aged 25 to 49 years [OR = 1.35 (95% CI: 1.08-1.70), p = 0.010] and 50 years and older [OR = 1.44 (95% CI: 1.06-1.97), p = 0.023)], Black Africans [OR = 1.61 (95% CI: 1.24-2.10), p < 0.001)], a high risk drinker [OR = 1.37 (95% CI: 1.02-1.83), p = 0.037], a hazardous drinker [OR = 4.76 (95% CI: 2.69-8.42), p < 0.001] and HIV positive, [OR = 1.79 (95% CI:1.55-2.08) p < 0.001], while lower likelihood of reporting psychological distress was significantly associated with being married [OR = 0.78 (95% CI: 0.62-0.98), p = 0.031), employed [OR = 0.71 (95% CI: 0.57-0.88), p = 0.002], and living in a rural formal area [OR = 0.73 (95% CI: 0.55-0.97), p = 0.033]. CONCLUSION: There is a need to develop strategies to alleviate psychological distress in the general population, with a particular focus on those who may be more vulnerable to distress such as females, the aged, excessive alcohol users, the unemployed, people living with HIV and those residing in urban areas as identified in the current findings.

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Globally intimate partner violence (IPV) is a public health problem that can be perpetrated by both males and females, although males are more likely to inflict severe IPV-related injuries on their female partners. In low- and middle-income countries like South Africa, few studies have conducted research to determine whether IPV perpetration by men may be a risk factor for engaging in other risk behaviours. The aim of this study is to determine whether IPV perpetration by men is a risk factor for engaging in other risk behaviours with a particular focus on risky sexual behaviours and alcohol misuse. The data for this study were drawn from a multilevel intervention study, which addressed the nexus of alcohol abuse and HIV prevention among men in South Africa. Men were screened and recruited from informal drinking places within 12 communities situated in one of the oldest, predominantly Xhosa-speaking African townships in Cape Town. Univariate and multivariate logistic regression models were used to analyse the associations between IVP and potential explanatory variables. Of the 975 men included in the survey, 39.9% reported to have been involved in Intimate Partner Violence. IPV perpetration was significantly more likely among men who reported having a child [OR 1.51 (1.07-2.14) p = .019], having a casual sexual partner [OR 1.51 (1.11-2.05) p = .008], and those with possible alcohol dependence [OR 3.46 (1.17-10.20) p = .024]. IPV was significantly less likely among men with matric educational qualification than those with no education [OR 0.30 (95% CI: 0.09-1.02) p = .053] and among those who reported using a condom at last sex [OR 0.69 (0.50-0.97) p = .034]. We therefore recommend that interventions aimed at reducing IPV need to address risky sexual and drinking behaviours amongst men simultaneously, while also focusing on intimate relationship power dynamics and gendered norms amongst couples.

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The malaria control programme of KwaZulu-Natal Province, South Africa, includes Mamfene and Mlambo communities. Western-type houses there are currently sprayed with deltamethrin, whereas traditional houses are sprayed with DDT for malaria control. In 2002, mosquitoes of the Anopheles gambiae complex (Diptera: Culicidae) were collected from DDT-sprayed houses, by window exit traps, and from man-baited nets outdoors. Larval collections were also carried out at Mzinweni Pan near Mlambo. Species of the An. gambiae complex were identified by rDNA polymerase chain reaction assay. The majority of samples collected by window trap and baited nets were identified as the malaria vector An. arabiensis Patton, with a few An. merus Dönitz and An. quadriannulatus (Theobald). The larval collections were predominantly An. quadriannulatus with a small number of An. arabiensis. Standard WHO insecticide susceptibility tests using 4% DDT and 0.05% deltamethrin were performed on both wild-caught females and laboratory-reared progeny from wild-caught females. Wild-caught An. arabiensis samples from window traps gave 63% and 100% mortality 24-h post-exposure to DDT or deltamethrin, respectively. Wild-caught An. arabiensis samples from man-baited net traps gave 81% mortality 24-h post-exposure to DDT. The F1 progeny from 22 An. arabiensis females showed average mortality of 86.5% 24-h post-exposure to DDT. Less than 80% mortality was recorded from five of these families. Biochemical analyses of samples from each of the families revealed comparatively high levels of glutathione-S-transferases and non-specific esterases in some families, but without significant correlation to bioassay results. Wild-caught An. quadriannulatus larvae were reared through to adults and assayed on 4% DDT, giving 47% (n = 36) mortality 24-h post-exposure. Finding DDT resistance in the vector An. arabiensis, close to the area where we previously reported pyrethroid-resistance in the vector An. funestus Giles, indicates an urgent need to develop a strategy of insecticide resistance management for the malaria control programmes of southern Africa.

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Northern Kwazulu/Natal (KZN) Province of South Africa borders on southern Mozambique, between Swaziland and the Indian Ocean. To control malaria vectors in KZN, houses were sprayed annually with residual DDT 2 g/ m2 until 1996 when the treatment changed to deltamethrin 20-25 mg/m2. At Ndumu (27 degrees 02'S, 32 degrees 19'E) the recorded malaria incidence increased more than six-fold between 1995 and 1999. Entomological surveys during late 1999 found mosquitoes of the Anopheles funestus group (Diptera: Culicidae) resting in sprayed houses in some sectors of Ndumu area. This very endophilic-vector of malaria had been eliminated from South Africa by DDT spraying in the 1950s, leaving the less endophilic An. arabiensis Patton as the only vector of known importance in KZN. Deltamethrin-sprayed houses at Ndumu were checked for insecticide efficacy by bioassay using susceptible An. arabiensis (laboratory-reared) that demonstrated 100% mortality. Members of the An. funestus group from Ndumu houses (29 males, 116 females) were identified by the rDNA PCR method and four species were found: 74 An. funestus Giles sensu stricto, 34 An. parensis Gillies, seven An. rivulorum Leeson and one An. leesoni Evans. Among An. funestus s.s. females, 5.4% (4/74) were positive for Plasmodium falciparum by ELISA and PCR tests. To test for pyrethroid resistance, mosquito adults were exposed to permethrin discriminating dosage and mortality scored 24h post-exposure: survival rates of wild-caught healthy males were 5/10 An. funestus, 1/9 An. rivulorum and 0/2 An. parensis; survival rates of laboratory-reared adult progeny from 19 An. funestus females averaged 14% (after 1h exposure to 1% permethrin 25:75cis:trans on papers in WHO test kits) and 27% (after 30 min in a bottle with 25 microg permethrin 40:60cis:trans). Anopheles funestus families showing >20% survival in these two resistance test procedures numbered 5/19 and 12/19, respectively. Progeny from 15 of the families were tested on 4% DDT impregnated papers and gave 100% mortality. Finding these proportions of pyrethroid-resistant An. funestus, associated with a malaria upsurge at Ndumu, has serious implications for malaria vector control operations in southern Africa.

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