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1.
PeerJ ; 12: e17018, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618571

RESUMO

The African leopard (Panthera pardus pardus) has lost a significant proportion of its historical range, notably in north-western Africa and South Africa. Recent studies have explored the genetic diversity and population structure of African leopards across the continent. A notable genetic observation is the presence of two divergent mitochondrial lineages, PAR-I and PAR-II. Both lineages appeared to be distributed widely, with PAR-II frequently found in southern Africa. Until now, no study has attempted to date the emergence of either lineage, assess haplotype distribution, or explore their evolutionary histories in any detail. To investigate these underappreciated questions, we compiled the largest and most geographically representative leopard data set of the mitochondrial NADH-5 gene to date. We combined samples (n = 33) collected in an altitudinal transect across the Mpumalanga province of South Africa, where two populations of leopard are known to be in genetic contact, with previously published sequences of African leopard (n = 211). We estimate that the maternal PAR-I and PAR-II lineages diverged approximately 0.7051 (0.4477-0.9632) million years ago (Ma). Through spatial and demographic analyses, we show that while PAR-I underwent a mid-Pleistocene population expansion resulting in several closely related haplotypes with little geographic structure across much of its range, PAR-II remained at constant size and may even have declined slightly in the last 0.1 Ma. The higher genetic drift experienced within PAR-II drove a greater degree of structure with little haplotype sharing and unique haplotypes in central Africa, the Cape, KwaZulu-Natal and the South African Highveld. The phylogeographic structure of PAR-II, with its increasing frequency southward and its exclusive occurrence in south-eastern South Africa, suggests that this lineage may have been isolated in South Africa during the mid-Pleistocene. This hypothesis is supported by historical changes in paleoclimate that promoted intense aridification around the Limpopo Basin between 1.0-0.6 Ma, potentially reducing gene flow and promoting genetic drift. Interestingly, we ascertained that the two nuclear DNA populations identified by a previous study as East and West Mpumalanga correspond to PAR-I and PAR-II, respectively, and that they have come into secondary contact in the Lowveld region of South Africa. Our results suggest a subdivision of African leopard mtDNA into two clades, with one occurring almost exclusively in South Africa, and we identify the potential environmental drivers of this observed structure. We caution that our results are based on a single mtDNA locus, but it nevertheless provides a hypothesis that can be further tested with a dense sample of nuclear DNA data, preferably whole genomes. If our interpretation holds true, it would provide the first genetic explanation for the smaller observed size of leopards at the southernmost end of their range in Africa.


Assuntos
Panthera , Animais , Panthera/genética , África do Sul , Evolução Biológica , Deriva Genética , DNA Mitocondrial/genética
2.
Front Vet Sci ; 11: 1356463, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681854

RESUMO

The pharmacokinetics and tolerability of cannabinoids and their metabolites were determined in eight horses after enteral administration of a commercial CBD/CBDA-rich hemp oil product. Each horse was administered 2 mg/kg or 8 mg/kg CBD/CBDA or no treatment in a randomized cross-over design. Serial serum samples collected over 48 h were analyzed by high performance liquid chromatography with tandem mass spectrometry. Plasma chemistry analysis was performed at 0 h and 24 h. Vital parameters, pedometry, and blinded mentation and gait evaluations were recorded at intervals up to 24 h. Manure production and gastrointestinal transit time were tracked for 48 h after oil administration. The median maximal concentration of CBD and CBDA were 5.2 and 36.95 ng/mL in the 2 mg/kg group, respectively; and 40.35 and 353.56 ng/mL in the 8 mg/kg group. The median half-life of elimination was not calculated for the 2 mg/kg CBD treatment due to lack of time points above the lower quantifiable limit beyond the Cmax while it was 7.75 h in the 8 mg/kg group. CBDA absorption was biphasic. Pharmacokinetic parameters for tetrahydrocannabinol, tetrahydrocannabinolic acid, cannabigerolic acid, and 7-carboxy cannabidiol are also reported. No significant differences in any of the measured tolerability parameters were demonstrated between treatment groups. Single-dose enteral administration of CBD/CBDA-rich hemp extract up to 8 mg/kg does not appear to produce neurologic, behavioral, or gastrointestinal effects in horses.

3.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38477357

RESUMO

Fertility is economically important but is hard to quantify and measure in breeding programs which has led extensive breeding programs to ignore fertility in their selection criteria. While female fertility traits have been extensively researched, male fertility traits have been largely ignored. It is estimated that 20% to 40% of bulls have sub-fertility, reducing the number of calves born and profits, highlighting the importance of investigating bull fertility. The most practical measure of male fertility is a bull breeding soundness evaluation (BBSE) which assesses structure as well as semen quality and quantity. Generally, traits recorded in a BBSE are neither genetically evaluated nor used for selection in breeding programs. All traits recorded during a BBSE were analyzed through a series of univariate and bivariate linear mixed models using a genomic relationship matrix to estimate genetic parameters. All genotype and phenotype data were obtained from a tropical composite commercial cattle population and imputed to 27,638 single-nucleotide polymorphisms (SNPs) with a total of 2,613 genotyped animals with BBSE records ranging from 616 to 826 animals depending on the trait. The heritabilities of the 27 traits recorded during a BBSE ranged from 0.02 to 0.49. Seven of the male fertility traits were recommended to be included in a breeding program based on their heritability and their phenotypic and genetic correlations. These traits are scrotal circumference, percent normal sperm, proximal droplets, distal midpiece reflex, knobbed acrosomes, vacuoles/teratoids, and sheath score. Using these seven traits in a breeding program would result in higher calving rates, increasing production and profitability.


One of the key profit drivers in any animal breeding program is fertility as it contributes directly to the progeny produced. Typically, fertility traits are hard to quantify and lowly heritable so they are often ignored in breeding programs. The inclusion of male fertility traits could allow for selection on heritable traits that are easy to measure and implement in a commercial breeding program. The utilization of male fertility traits could improve overall fertility and production. Bull breeding soundness evaluation traits were heritable, ranging from low to high, allowing for genetic improvement in those traits. Seven traits were recommended as selection criteria in a breeding program, which included two physical traits and five sperm traits. Implementing these seven traits in a breeding program would allow for a higher calving rate and associated increased profits.


Assuntos
Análise do Sêmen , Sêmen , Bovinos/genética , Masculino , Animais , Feminino , Análise do Sêmen/veterinária , Fenótipo , Fertilidade/genética , Reprodução
4.
Diabetes Obes Metab ; 26(5): 1658-1669, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38312016

RESUMO

AIM: Myo-inositol supplementation from ~13 weeks' gestation reportedly improves glycaemia regulation in metabolically at-risk women, with speculation that earlier supplementation might bring further improvement. However, the NiPPeR trial of a myo-inositol-containing supplement starting preconception did not lower gestational glycaemia in generally healthy women. We postulated that the earlier timing of supplementation influences the maternal metabolic adaptation for gestational glycaemia regulation. METHODS: In total, 585 women were recruited from Singapore, UK and New Zealand for the NiPPeR study. We examined associations of plasma myo-inositol concentrations at 7 and 28 weeks' gestation with 28 weeks plasma glucose (PG; fasting, and 1 h and 2 h in 75 g oral glucose tolerance test) and insulin indices using linear regression adjusting for covariates. RESULTS: Higher 7-week myo-inositol, but not 28-week myo-inositol, associated with higher 1 h PG [ßadj (95% confidence intervals) 0.05 (0.01, 0.09) loge mmol/L per loge µmol/L, p = .022] and 2 h PG [0.08 (0.03, 0.12), p = .001]; equivalent to 0.39 mmol/L increase in 2 h PG for an average 7-week myo-inositol increase of 23.4 µmol/L with myo-inositol supplementation. Higher 7-week myo-inositol associated with a lower 28-week Stumvoll index (first phase), an approximation of insulin secretion [-0.08 (-0.15, -0.01), p = .020] but not with 28-week Matsuda insulin sensitivity index. However, the clinical significance of a 7-week myo-inositol-related increase in glycaemia was limited as there was no association with gestational diabetes risk, birthweight and cord C-peptide levels. In-silico modelling found higher 28-week myo-inositol was associated with lower gestational glycaemia in White, but not Asian, women after controlling for 7-week myo-inositol effects. CONCLUSION: To our knowledge, our study provides the first evidence that increasing first trimester plasma myo-inositol may slightly exacerbate later pregnancy post-challenge glycaemia, indicating that the optimal timing for starting prenatal myo-inositol supplementation needs further investigation.


Assuntos
Diabetes Gestacional , Inositol , Gravidez , Feminino , Humanos , Inositol/uso terapêutico , Diabetes Gestacional/tratamento farmacológico , Suplementos Nutricionais , Teste de Tolerância a Glucose , Insulina
5.
J Appl Psychol ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300539

RESUMO

Every day, people perform internal (e.g., thoughts) and external (e.g., behaviors) activities to repair, strengthen, or revise their identities at work. Despite organizations being the main stage on which this identity work (IW) occurs and a major contextual element invoking identity work, scholars still lack an understanding of employees' beliefs about their organizations' support for identity work. In this research, we conceptualize and operationalize identity work support perceptions (IWSP)-defined as the degree to which employees perceive that their organization encourages, allows, or provides opportunities to think about, talk about, or display aspects of work and nonwork identities, or engage in activities that foster understanding and sharing of identities. We develop a scale to measure four dimensions (i.e., cognitive, discursive, behavioral, and physical) of IWSP using seven empirical samples (two samples of subject matter experts and five samples of employed adults). We provide evidence of reliability, as well as content, convergent, and discriminant validity with constructs in IWSP's nomological network and IWSP's incremental predictive ability of attitudinal and behavioral outcomes. Implications of our findings for research and practice are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

6.
BMJ Open ; 14(2): e074625, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38320845

RESUMO

INTRODUCTION: Autism (formally autism spectrum disorder) encompasses a group of complex neurodevelopmental conditions, characterised by differences in communication and social interactions. Co-occurring chronic gastrointestinal symptoms are common among autistic individuals and can adversely affect their quality of life. This study aims to evaluate the efficacy of oral encapsulated faecal microbiome transfer (FMT) in improving gastrointestinal symptoms and well-being among autistic adolescents and adults. METHODS AND ANALYSIS: This double-blind, randomised, placebo-controlled trial will recruit 100 autistic adolescents and adults aged 16-45 years, who have mild to severe gastrointestinal symptoms (Gastrointestinal Symptoms Rating Scale (GSRS) score ≥2.0). We will also recruit eight healthy donors aged 18-32 years, who will undergo extensive clinical screening. Recipients will be randomised 1:1 to receive FMT or placebo, stratified by biological sex. Capsules will be administered over two consecutive days following an overnight bowel cleanse with follow-up assessments at 6, 12 and 26 weeks post-treatment. The primary outcome is GSRS score at 6 weeks. Other assessments include anthropometry, body composition, hair cortisol concentration, gut microbiome profile, urine/plasma gut-derived metabolites, plasma markers of gut inflammation/permeability and questionnaires on general well-being, sleep quality, physical activity, food diversity and treatment tolerability. Adverse events will be recorded and reviewed by an independent data monitoring committee. ETHICS AND DISSEMINATION: Ethics approval for the study was granted by the Central Health and Disability Ethics Committee on 24 August 2021 (reference number: 21/CEN/211). Results will be published in peer-reviewed journals and presented to both scientific and consumer group audiences. TRIAL REGISTRATION NUMBER: ACTRN12622000015741.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Gastroenteropatias , Microbioma Gastrointestinal , Adulto , Humanos , Adolescente , Transtorno Autístico/terapia , Transtorno do Espectro Autista/terapia , Transplante de Microbiota Fecal/métodos , Qualidade de Vida , Gastroenteropatias/terapia , Método Duplo-Cego , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Children (Basel) ; 11(2)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38397358

RESUMO

Whanau Pakari is a healthy lifestyle assessment and intervention programme for children and adolescents with obesity in Taranaki (Aotearoa/New Zealand), which, in this region, replaced the nationally funded Green Prescription Active Families (GRxAF) programme. We compared national referral rates from the GRxAF programme (age 5-15 years) and the B4 School Check (B4SC, a national preschool health and development assessment) with referral rates in Taranaki from Whanau Pakari. We retrospectively analysed 5 years of clinical data (2010-2015), comparing referral rates before, during, and after the Whanau Pakari clinical trial, which was embedded within the programme. We also surveyed programme referrers and stakeholders about their experiences of Whanau Pakari, analysing their responses using a multiple-methods framework. After the Whanau Pakari trial commenced, Taranaki GRxAF referral rates increased markedly (2.3 pretrial to 7.2 per 1000 person-years), while NZ rates were largely unchanged (1.8-1.9 per 1000 person-years) (p < 0.0001 for differences during the trial). Post-trial, Taranaki GRxAF referral rates remained higher irrespective of ethnicity, being 1.8 to 3.2 times the national rates (p < 0.001). Taranaki B4SC referrals for obesity were nearly complete at 99% in the last trial year and 100% post-trial, compared with national rates threefold lower (31% and 32%, respectively; p < 0.0001), with Taranaki referral rates for extreme obesity sustained at 80% and exceeding national rates for both periods (58% and 62%, respectively; p < 0.01). Notably, a referral was 50% more likely for referrers who attended a Whanau Pakari training half-day (RR = 1.51; p = 0.009). Stakeholders credited the success of Whanau Pakari to its multidisciplinary team, family-centred approach, and home-based assessments. However, they highlighted challenges such as navigating multidisciplinary collaboration, engaging with families with complex needs, and shifting conventional healthcare practices. Given its favourable referral trends and stakeholder endorsement, Whanau Pakari appears to be a viable contemporary model for an accessible and culturally appropriate intervention on a national and potentially international scale.

8.
Microbiome ; 12(1): 26, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347627

RESUMO

BACKGROUND: Horizontal gene transfer (HGT) describes the transmission of DNA outside of direct ancestral lineages. The process is best characterised within the bacterial kingdom and can enable the acquisition of genetic traits that support bacterial adaptation to novel niches. The adaptation of bacteria to novel niches has particular relevance for faecal microbiota transplantation (FMT), a therapeutic procedure which aims to resolve gut-related health conditions of individuals, through transplanted gut microbiota from healthy donors. RESULTS: Three hundred eighty-one stool metagenomic samples from a placebo-controlled FMT trial for obese adolescents (the Gut Bugs Trial) were analysed for HGT, using two complementary methodologies. First, all putative HGT events, including historical HGT signatures, were quantified using the bioinformatics application WAAFLE. Second, metagenomic assembly and gene clustering were used to assess and quantify donor-specific genes transferred to recipients following the intervention. Both methodologies found no difference between the level of putative HGT events in the gut microbiomes of FMT and placebo recipients, post-intervention. HGT events facilitated by engrafted donor species in the FMT recipient gut at 6 weeks post-intervention were identified and characterised. Bacterial strains contributing to this subset of HGT events predominantly belonged to the phylum Bacteroidetes. Engraftment-dependent horizontally transferred genes were retained within recipient microbiomes at 12 and 26 weeks post-intervention. CONCLUSION: Our study suggests that novel microorganisms introduced into the recipient gut following FMT have no impact on the basal rate of HGT within the human gut microbiome. Analyses of further FMT studies are required to assess the generalisability of this conclusion across different FMT study designs and for the treatment of different gut-related conditions. Video Abstract.


Assuntos
Microbioma Gastrointestinal , Microbiota , Obesidade Infantil , Adolescente , Humanos , Transplante de Microbiota Fecal/métodos , Transferência Genética Horizontal , Microbioma Gastrointestinal/genética , Bactérias/genética , Fezes/microbiologia , Resultado do Tratamento
9.
Proc Natl Acad Sci U S A ; 121(7): e2306993121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315848

RESUMO

Puromycin is covalently added to the nascent chain of proteins by the peptidyl transferase activity of the ribosome and the dissociation of the puromycylated peptide typically follows this event. It was postulated that blocking the translocation of the ribosome with emetine could retain the puromycylated peptide on the ribosome, but evidence against this has recently been published [Hobson et al., Elife 9, e60048 (2020); and Enam et al., Elife 9, e60303 (2020)]. In neurons, puromycylated nascent chains remain in the ribosome even in the absence of emetine, yet direct evidence for this has been lacking. Using biochemistry and cryoelectron microscopy, we show that the puromycylated peptides remain in the ribosome exit channel in the large subunit in a subset of neuronal ribosomes stalled in the hybrid state. These results validate previous experiments to localize stalled polysomes in neurons and provide insight into how neuronal ribosomes are stalled. Moreover, in these hybrid-state neuronal ribosomes, anisomycin, which usually blocks puromycylation, competes poorly with puromycin in the puromycylation reaction, allowing a simple assay to determine the proportion of nascent chains that are stalled in this state. In early hippocampal neuronal cultures, over 50% of all nascent peptides are found in these stalled polysomes. These results provide insights into the stalling mechanisms of neuronal ribosomes and suggest that puromycylated peptides can be used to reveal subcellular sites of hybrid-state stalled ribosomes in neurons.


Assuntos
Emetina , Ribossomos , Puromicina/farmacologia , Microscopia Crioeletrônica , Emetina/análise , Emetina/metabolismo , Ribossomos/metabolismo , Biossíntese de Proteínas , Peptídeos/metabolismo , Neurônios/metabolismo
10.
Microb Ecol ; 87(1): 39, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38332161

RESUMO

In the 2019-2020 summer, wildfires decimated the Australian bush environment and impacted wildlife species, including koalas (Phascolarctos cinereus) and grey headed flying fox pups (Pteropid bats, Pteropus poliocephalus). Consequently, hundreds of koalas and thousands of bat pups entered wildlife hospitals with fire-related injuries/illness, where some individuals received antimicrobial therapy. This study investigated the dynamics of antimicrobial resistance (AMR) in pre-fire, fire-affected and post-fire koalas and Pteropid bat pups. PCR and DNA sequencing were used to screen DNA samples extracted from faeces (koalas and bats) and cloacal swabs (koalas) for class 1 integrons, a genetic determinant of AMR, and to identify integron-associated antibiotic resistance genes. Class 1 integrons were detected in 25.5% of koalas (68 of 267) and 59.4% of bats (92 of 155). Integrons contained genes conferring resistance to aminoglycosides, trimethoprim and beta-lactams. Samples were also screened for blaTEM (beta-lactam) resistance genes, which were detected in 2.6% of koalas (7 of 267) and 25.2% of bats (39 of 155). Integron occurrence was significantly higher in fire-affected koalas in-care compared to wild pre-fire koalas (P < 0.0001). Integron and blaTEM occurrence were not significantly different in fire-affected bats compared to pre-fire bats (P > 0.05), however, their occurrence was significantly higher in fire-affected bats in-care compared to wild fire-affected bats (P < 0.0001 and P = 0.0488 respectively). The observed shifts of AMR dynamics in wildfire-impacted species flags the need for judicious antibiotic use when treating fire-affected wildlife to minimise unwanted selective pressure and negative treatment outcomes associated with carriage of resistance genes and antibiotic resistant bacteria.


Assuntos
Quirópteros , Phascolarctidae , Incêndios Florestais , Humanos , Animais , Antibacterianos/farmacologia , Austrália , Farmacorresistência Bacteriana/genética , Animais Selvagens
11.
Radiographics ; 44(2): e230075, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38271257

RESUMO

Lymphatic flow and anatomy can be challenging to study, owing to variable lymphatic anatomy in patients with diverse primary or secondary lymphatic pathologic conditions and the fact that lymphatic imaging is rarely performed in healthy individuals. The primary components of the lymphatic system outside the head and neck are the peripheral, retroperitoneal, mesenteric, hepatic, and pulmonary lymphatic systems and the thoracic duct. Multiple techniques have been developed for imaging components of the lymphatic system over the past century, with trade-offs in spatial, temporal, and contrast resolution; invasiveness; exposure to ionizing radiation; and the ability to obtain information on dynamic lymphatic flow. More recently, dynamic contrast-enhanced (DCE) MR lymphangiography (MRL) has emerged as a valuable tool for imaging both lymphatic flow and anatomy in a variety of congenital and acquired primary or secondary lymphatic disorders. The authors provide a brief overview of lymphatic physiology, anatomy, and imaging techniques. Next, an overview of DCE MRL and the development of an MRL practice and workflow in a hybrid interventional MRI suite incorporating cart-based in-room US is provided, with an emphasis on multidisciplinary collaboration. The spectrum of congenital and acquired lymphatic disorders encountered early in an MRL practice is provided, with emphasis on the diversity of imaging findings and how DCE MRL can aid in diagnosis and treatment of these patients. Methods such as DCE MRL for assessing the hepatic and mesenteric lymphatic systems and emerging technologies that may further expand DCE MRL use such as three-dimensional printing are introduced. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.


Assuntos
Doenças Linfáticas , Linfografia , Humanos , Linfografia/métodos , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Doenças Linfáticas/diagnóstico por imagem , Doenças Linfáticas/patologia , Sistema Linfático/patologia
12.
BMC Med ; 22(1): 39, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38287349

RESUMO

BACKGROUND: Nutritional intervention preconception and throughout pregnancy has been proposed as an approach to promoting healthy postnatal weight gain in the offspring but few randomised trials have examined this. METHODS: Measurements of weight and length were obtained at multiple time points from birth to 2 years among 576 offspring of women randomised to receive preconception and antenatally either a supplement containing myo-inositol, probiotics, and additional micronutrients (intervention) or a standard micronutrient supplement (control). We examined the influence on age- and sex-standardised BMI at 2 years (WHO standards, adjusting for study site, sex, maternal parity, smoking and pre-pregnancy BMI, and gestational age), together with the change in weight, length, BMI from birth, and weight gain trajectories using latent class growth analysis. RESULTS: At 2 years, there was a trend towards lower mean BMI among intervention offspring (adjusted mean difference [aMD] - 0.14 SD [95% CI 0.30, 0.02], p = 0.09), and fewer had a BMI > 95th percentile (i.e. > 1.65 SD, 9.2% vs 18.0%, adjusted risk ratio [aRR] 0.51 [95% CI 0.31, 0.82], p = 0.006). Longitudinal data revealed that intervention offspring had a 24% reduced risk of experiencing rapid weight gain > 0.67 SD in the first year of life (21.9% vs 31.1%, aRR 0.76 [95% CI 0.58, 1.00], p = 0.047). The risk was likewise decreased for sustained weight gain > 1.34 SD in the first 2 years of life (7.7% vs 17.1%, aRR 0.55 [95% CI 0.34, 0.88], p = 0.014). From five weight gain trajectories identified, there were more intervention offspring in the "normal" weight gain trajectory characterised by stable weight SDS around 0 SD from birth to 2 years (38.8% vs 30.1%, RR 1.29 [95% CI 1.03, 1.62], p = 0.029). CONCLUSIONS: Supplementation with myo-inositol, probiotics, and additional micronutrients preconception and in pregnancy reduced the incidence of rapid weight gain and obesity at 2 years among offspring. Previous reports suggest these effects will likely translate to health benefits, but longer-term follow-up is needed to evaluate this. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02509988 (Universal Trial Number U1111-1171-8056). Registered on 16 July 2015.


Assuntos
Trajetória do Peso do Corpo , Probióticos , Feminino , Humanos , Gravidez , Índice de Massa Corporal , Suplementos Nutricionais , Inositol , Micronutrientes , Aumento de Peso
13.
Vet Dermatol ; 35(2): 156-165, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37749747

RESUMO

BACKGROUND: Topical therapy is essential in assisting with the resolution of pyoderma. OBJECTIVES: (i) Evaluate the in vitro efficacy and residual activity of two different hair segments treated with shampoo and mousse against meticillin-sensitive and meticillin-resistant staphylococci; (ii) compare proximal and distal hair portions treated with the products and (iii) describe a new disc diffusion method for assessing residual efficacy. ANIMALS: Eleven privately owned, medium-haired dogs. MATERIALS AND METHODS: In this randomised, blinded and negatively controlled study, dogs were treated once with a 3% chlorhexidine digluconate-0.5% ophytrium shampoo on the lateral thorax, and the corresponding mousse on the opposite side. Hairs were plucked before treatment, two hours post-treatment, and day (D)2, D4, D7, D10 and D14. Hairs were weighed (0.01 g) and cut (1.0 cm) from the proximal portion, moistened with saline and placed on a sterile diffusion disc to absorb the solution. Proximal and distal hair bundles and diffusion discs were placed onto agar inoculated with an isolate of meticillin-sensitive or meticillin-resistant Staphylococcus pseudintermedius or Staphylococcus schleiferi. Inhibition zones were measured following incubation. RESULTS: Distal hairs had larger (p < 0.001) inhibition zones compared to proximal hairs. Mousse had significant differences (p < 0.05) between time points and locations for both the hair bundles and discs, while shampoo only had a significant difference (p < 0.001) between time points for the hairs. CONCLUSIONS AND CLINICAL RELEVANCE: Mousse was effective, and shampoo was only minimally effective in inhibiting bacterial growth in vitro, with the greatest effect occurring at the two hours time point. The distal hair shafts had greater inhibition.


Assuntos
Anti-Infecciosos , Doenças do Cão , Staphylococcus aureus Resistente à Meticilina , Staphylococcus , Animais , Cães , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Doenças do Cão/tratamento farmacológico , Doenças do Cão/microbiologia , Cabelo , Meticilina/farmacologia , Testes de Sensibilidade Microbiana/veterinária
14.
Appl Environ Microbiol ; 90(1): e0166023, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38117061

RESUMO

The platform chemical cis,cis-muconic acid (ccMA) provides facile access to a number of monomers used in the synthesis of commercial plastics. It is also a metabolic intermediate in the ß-ketoadipic acid pathway of many bacteria and, therefore, a current target for microbial production from abundant renewable resources via metabolic engineering. This study investigates Novosphingobium aromaticivorans DSM12444 as a chassis for the production of ccMA from biomass aromatics. The N. aromaticivorans genome predicts that it encodes a previously uncharacterized protocatechuic acid (PCA) decarboxylase and a catechol 1,2-dioxygenase, which would be necessary for the conversion of aromatic metabolic intermediates to ccMA. This study confirmed the activity of these two enzymes in vitro and compared their activity to ones that have been previously characterized and used in ccMA production. From these results, we generated one strain that is completely derived from native genes and a second that contains genes previously used in microbial engineering synthesis of this compound. Both of these strains exhibited stoichiometric production of ccMA from PCA and produced greater than 100% yield of ccMA from the aromatic monomers that were identified in liquor derived from alkaline pretreated biomass. Our results show that a strain completely derived from native genes and one containing homologs from other hosts are both capable of stoichiometric production of ccMA from biomass aromatics. Overall, this work combines previously unknown aspects of aromatic metabolism in N. aromaticivorans and the genetic tractability of this organism to generate strains that produce ccMA from deconstructed biomass.IMPORTANCEThe production of commodity chemicals from renewable resources is an important goal toward increasing the environmental and economic sustainability of industrial processes. The aromatics in plant biomass are an underutilized and abundant renewable resource for the production of valuable chemicals. However, due to the chemical composition of plant biomass, many deconstruction methods generate a heterogeneous mixture of aromatics, thus making it difficult to extract valuable chemicals using current methods. Therefore, recent efforts have focused on harnessing the pathways of microorganisms to convert a diverse set of aromatics into a single product. Novosphingobium aromaticivorans DSM12444 has the native ability to metabolize a wide range of aromatics and, thus, is a potential chassis for conversion of these abundant compounds to commodity chemicals. This study reports on new features of N. aromaticivorans that can be used to produce the commodity chemical cis,cis-muconic acid from renewable and abundant biomass aromatics.


Assuntos
Hidroxibenzoatos , Sphingomonadaceae , Biomassa , Sphingomonadaceae/metabolismo , Ácido Sórbico/metabolismo , Lignina/metabolismo , Engenharia Metabólica
15.
PLoS Med ; 20(12): e1004260, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38051700

RESUMO

BACKGROUND: Maternal vitamin status preconception and during pregnancy has important consequences for pregnancy outcome and offspring development. Changes in vitamin status from preconception through early and late pregnancy and postpartum have been inferred from cross-sectional data, but longitudinal data on vitamin status from preconception throughout pregnancy and postdelivery are sparse. As such, the influence of vitamin supplementation on vitamin status during pregnancy remains uncertain. This study presents one prespecified outcome from the randomized controlled NiPPeR trial, aiming to identify longitudinal patterns of maternal vitamin status from preconception, through early and late pregnancy, to 6 months postdelivery, and determine the influence of vitamin supplementation. METHODS AND FINDINGS: In the NiPPeR trial, 1,729 women (from the United Kingdom, Singapore, and New Zealand) aged 18 to 38 years and planning conception were randomized to receive a standard vitamin supplement (control; n = 859) or an enhanced vitamin supplement (intervention; n = 870) starting in preconception and continued throughout pregnancy, with blinding of participants and research staff. Supplement components common to both treatment groups included folic acid, ß-carotene, iron, calcium, and iodine; components additionally included in the intervention group were riboflavin, vitamins B6, B12, and D (in amounts available in over-the-counter supplements), myo-inositol, probiotics, and zinc. The primary outcome of the study was glucose tolerance at 28 weeks' gestation, measured by oral glucose tolerance test. The secondary outcome reported in this study was the reduction in maternal micronutrient insufficiency in riboflavin, vitamin B6, vitamin B12, and vitamin D, before and during pregnancy. We measured maternal plasma concentrations of B-vitamins, vitamin D, and markers of insufficiency/deficiency (homocysteine, hydroxykynurenine-ratio, methylmalonic acid) at recruitment, 1 month after commencing intervention preconception, in early pregnancy (7 to 11 weeks' gestation) and late pregnancy (around 28 weeks' gestation), and postdelivery (6 months after supplement discontinuation). We derived standard deviation scores (SDS) to characterize longitudinal changes among participants in the control group and measured differences between the 2 groups. At recruitment, the proportion of patients with marginal or low plasma status was 29.2% for folate (<13.6 nmol/L), 7.5% and 82.0% for riboflavin (<5 nmol/L and ≤26.5 nmol/L, respectively), 9.1% for vitamin B12 (<221 pmol/L), and 48.7% for vitamin D (<50 nmol/L); these proportions were balanced between the groups. Over 90% of all participants had low or marginal status for one or more of these vitamins at recruitment. Among participants in the control group, plasma concentrations of riboflavin declined through early and late pregnancy, whereas concentrations of 25-hydroxyvitamin D were unchanged in early pregnancy, and concentrations of vitamin B6 and B12 declined throughout pregnancy, becoming >1 SDS lower than baseline by 28 weeks gestation. In the control group, 54.2% of participants developed low late-pregnancy vitamin B6 concentrations (pyridoxal 5-phosphate <20 nmol/L). After 1 month of supplementation, plasma concentrations of supplement components were substantially higher among participants in the intervention group than those in the control group: riboflavin by 0.77 SDS (95% CI 0.68 to 0.87, p < 0.0001), vitamin B6 by 1.07 SDS (0.99 to 1.14, p < 0.0001), vitamin B12 by 0.55 SDS (0.46 to 0.64, p < 0.0001), and vitamin D by 0.51 SDS (0.43 to 0.60, p < 0.0001), with higher levels in the intervention group maintained during pregnancy. Markers of vitamin insufficiency/deficiency were reduced in the intervention group, and the proportion of participants with vitamin D insufficiency (<50 nmol/L) during late pregnancy was lower in the intervention group (35.1% versus 8.5%; p < 0.0001). Plasma vitamin B12 remained higher in the intervention group than in the control group 6 months postdelivery (by 0.30 SDS (0.14, 0.46), p = 0.0003). The main limitation is that generalizability to the global population is limited by the high-resource settings and the lack of African and Amerindian women in particular. CONCLUSIONS: Over 90% of the trial participants had marginal or low concentrations of one or more of folate, riboflavin, vitamin B12, or vitamin D during preconception, and many developed markers of vitamin B6 deficiency in late pregnancy. Preconception/pregnancy supplementation in amounts available in over-the-counter supplements substantially reduces the prevalence of vitamin deficiency and depletion markers before and during pregnancy, with higher maternal plasma vitamin B12 maintained during the recommended lactational period. TRIAL REGISTRATION: ClinicalTrials.gov NCT02509988; U1111-1171-8056.


Assuntos
Ácido Fólico , Complexo Vitamínico B , Feminino , Humanos , Gravidez , Estudos Transversais , Suplementos Nutricionais , Resultado da Gravidez , Riboflavina , Vitamina B 12 , Vitamina B 6 , Vitamina D , Adolescente , Adulto Jovem , Adulto
16.
One Health ; 17: 100652, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38024267

RESUMO

Growing reports of diverse antibiotic resistance genes in wildlife species around the world symbolises the extent of this global One Health issue. The health of wildlife is threatened by antimicrobial resistance in situations where wildlife species develop disease and require antibiotics. Chlamydial disease is a key threat for koalas in Australia, with infected koalas frequently entering wildlife hospitals and requiring antibiotic therapy, typically with chloramphenicol or doxycycline. This study investigated the occurrence and diversity of target chloramphenicol and doxycycline resistance genes (cat and tet respectively) in koala urogenital and faecal microbiomes. DNA was extracted from 394 urogenital swabs and 91 faecal swabs collected from koalas in mainland Australia and on Kangaroo Island (KI) located 14 km off the mainland, before (n = 145) and during (n = 340) the 2019-2020 wildfires. PCR screening and DNA sequencing determined 9.9% of samples (95%CI: 7.5% to 12.9%) carried cat and/or tet genes, with the highest frequency in fire-affected KI koalas (16.8%) and the lowest in wild KI koalas sampled prior to fires (6.5%). The diversity of cat and tet was greater in fire-affected koalas (seven variants detected), compared to pre-fire koalas (two variants detected). Fire-affected koalas in care that received antibiotics had a significantly higher proportion (p < 0.05) of cat and/or tet genes (37.5%) compared to koalas that did not receive antibiotics (9.8%). Of the cat and/or tet positive mainland koalas, 50.0% were Chlamydia-positive by qPCR test. Chloramphenicol and doxycycline resistance genes in koala microbiomes may contribute to negative treatment outcomes for koalas receiving anti-chlamydial antibiotics. Thus a secondary outcome of wildfires is increased risk of acquisition of cat and tet genes in fire-affected koalas that enter care, potentially exacerbating the already significant threat of chlamydial disease on Australia's koalas. This study highlights the importance of considering impacts to wildlife health within the One Health approach to AMR and identifies a need for greater understanding of AMR ecology in wildlife.

17.
Appl Environ Microbiol ; 89(12): e0126823, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38014958

RESUMO

IMPORTANCE: There is economic and environmental interest in generating commodity chemicals from renewable resources, such as lignocellulosic biomass, that can substitute for chemicals derived from fossil fuels. The bacterium Novosphingobium aromaticivorans is a promising microbial platform for producing commodity chemicals from lignocellulosic biomass because it can produce these from compounds in pretreated lignocellulosic biomass, which many industrial microbial catalysts cannot metabolize. Here, we show that N. aromaticivorans can be engineered to produce several valuable carotenoids. We also show that engineered N. aromaticivorans strains can produce these lipophilic chemicals concurrently with the extracellular commodity chemical 2-pyrone-4,6-dicarboxylic acid when grown in a complex liquor obtained from alkaline pretreated lignocellulosic biomass. Concurrent microbial production of valuable intra- and extracellular products can increase the economic value generated from the conversion of lignocellulosic biomass-derived compounds into commodity chemicals and facilitate the separation of water- and membrane-soluble products.


Assuntos
Biocombustíveis , Lignina , Biomassa , Lignina/metabolismo , Catálise
18.
Sci Rep ; 13(1): 20216, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980443

RESUMO

The presynaptic release apparatus can be specialized to enable specific synaptic functions. Habituation is the diminishing of a physiological response to a frequently repeated stimulus and in Aplysia, habituation to touch is mediated by a decrease in transmitter release from the sensory neurons that respond to touch even after modest rates of action potential firing. This synaptic depression is not common among Aplysia synaptic connections suggesting the presence of a release apparatus specialized for this depression. We found that specific splice forms of ApCaV2, the calcium channel required for transmitter release, are preferentially used in sensory neurons, consistent with a specialized release apparatus. However, we were not able to find a specific ApCaV2 splice uniquely required for synaptic depression. The C-terminus of ApCaV2 alpha1 subunit retains conserved binding to Aplysia rab-3 interacting molecule (ApRIM) and ApRIM-binding protein (ApRBP) and the C-terminus is required for full synaptic expression of ApCaV2. We also identified a splice form of ApRIM that did not interact with the ApCav2 alpha 1 subunit, but it was not preferentially used in sensory neurons.


Assuntos
Aplysia , Canais de Cálcio , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Aplysia/metabolismo , Células Receptoras Sensoriais/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Potenciais de Ação , Transmissão Sináptica/fisiologia , Sinapses/metabolismo , Cálcio/metabolismo
19.
Front Nutr ; 10: 1282376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915619

RESUMO

Rational: Maternal overweight/obesity and gestational diabetes mellitus (GDM) are associated with an increased risk of their offspring developing overweight/obesity or type 2 diabetes later in life. However, the impacts of maternal overweight/obesity and dysglycemia on human milk (HM) macronutrient composition are not well understood. Objective: Through a double-blind randomised controlled trial, we investigated the effects of maternal supplementation from preconception throughout pregnancy until birth on HM macronutrient concentrations, in association with maternal and infant factors including maternal pre-pregnancy body mass index (BMI) and GDM status. In addition, we aimed to characterise longitudinal changes in HM macronutrients. Methods: The control supplement contained calcium, iodine, iron, ß-carotene, and folic acid. The intervention supplement additionally contained zinc, vitamins B2, B6, B12, and D3, probiotics, and myo-inositol. HM samples were collected across seven time points from 1 week to 12 months from Singapore and/or New Zealand. HM macronutrient concentrations were measured using a MIRIS Human Milk Analyser. Potential differences in HM macronutrient concentrations were assessed using linear mixed models with a repeated measures design. Results: Overall, HM macronutrient concentrations were similar between control and intervention groups. Among the control group, overweight/obesity and GDM were associated with higher HM fat and energy concentrations over the first 3 months. Such associations were not observed among the intervention group. Of note, mothers with GDM in the intervention group had lower HM fat by 10% (p = 0.049) and energy by 6% (p = 0.029) than mothers with GDM in the control group. Longitudinal changes in HM macronutrient concentrations over 12 months of lactation in New Zealand showed that HM fat and energy decreased in the first 6 months then increased until 12 months. HM lactose gradually decreased from 1 week to 12 months while crude protein decreased from 1 week to 6 months then remained relatively constant until 12 months of lactation. Conclusion: Maternal overweight/obesity or GDM were associated with increased HM fat and energy levels. We speculate the intervention taken during preconception and pregnancy altered the impact of maternal BMI or GDM status on HM macronutrient composition. Further studies are required to identify the mechanisms underlying altered HM macronutrient concentration in the intervention group and to determine any long-term effects on offspring health. Clinical trial registration: ClinicalTrials.gov, NCT02509988, Universal Trial Number U1111-1171-8056. Registered on 16 July 2015. This is an academic-led study by the EpiGen Global Research Consortium.

20.
Vet Dermatol ; 34(6): 554-566, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37700599

RESUMO

BACKGROUND: Oclacitinib (Apoquel; Zoetis) has been reported to be beneficial for treating immune-mediated disorders. HYPOTHESIS/OBJECTIVES: This retrospective study evaluates in which group of dogs [oclacitinib (OC) or azathioprine (AZ)] remission of pemphigus foliaceus (PF) was more effectively achieved with matched induction dosing of glucocorticoids; it further evaluates which group had a higher glucocorticoid-sparing effect. ANIMALS: Review of 30 medical records of dogs diagnosed with PF presented to a private practice dermatological service. MATERIALS AND METHODS: Retrospective analysis of dogs diagnosed with PF and treated with OC or AZ in combination with glucocorticoids. RESULTS: There was no significant difference in the ability to induce remission between AZ and OC groups. In the AZ group, 13 of 15 dogs went into some type of remission (partial or complete), compared with 11 of 15 in the OC group. There was no significant difference between the two groups for the glucocorticoid-sparing effect. The AZ group had an average reduction of 77.9% from the induction glucocorticoid dose, and OC group had an average reduction of 64.4%. One of 15 patients in the AZ group and three of 15 patients in the OC group had a 100% reduction of the glucocorticoid dose. CONCLUSIONS AND CLINICAL RELEVANCE: These results indicate that OC can be considered as a treatment option for canine PF.


Assuntos
Doenças do Cão , Pênfigo , Humanos , Cães , Animais , Pênfigo/tratamento farmacológico , Pênfigo/veterinária , Azatioprina/uso terapêutico , Glucocorticoides/uso terapêutico , Estudos Retrospectivos , Doenças do Cão/tratamento farmacológico
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