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1.
Vet Parasitol Reg Stud Reports ; 54: 101086, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39237230

RESUMO

Trichinella infections have been eliminated from pork where pigs are raised in biosecure facilities, but wildlife infections persist. Trichinella murrelli is the primary zoonotic species in wild carnivores in the United States, having been identified in several species of omnivores and carnivores. Here, we document its occurrence in seven of 21 (33.3%) red foxes (Vulpes vulpes) from six counties in Pennsylvania. Encysted Trichinella larvae were detected in muscle squashes (<5 g samples) of all seven foxes, and in histological sections of the tongue and limb muscle of three. Larvae from muscle squashes were pooled and tested in a multiplex PCR capable of differentiating all Trichinella species native to the USA; all samples contained only T. murrelli. This is the first identification of T. murrelli in red foxes from Pennsylvania, and the first such survey performed in the last three decades. Results indicate that Trichinella remains endemic in Pennsylvania wildlife and a threat to the health of those who consume wild game.


Assuntos
Raposas , Trichinella , Triquinelose , Animais , Raposas/parasitologia , Triquinelose/veterinária , Triquinelose/parasitologia , Triquinelose/epidemiologia , Pennsylvania/epidemiologia , Trichinella/isolamento & purificação , Trichinella/classificação , Feminino , Animais Selvagens/parasitologia , Masculino , Larva/classificação
2.
Vet Parasitol Reg Stud Reports ; 54: 101092, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39237242

RESUMO

BACKGROUND: Canine babesiosis and ehrlichiosis are tick-borne infections of great significance in South Africa. Theileriosis in dogs in South Africa is still poorly understood. Co-infection with multiple tick-borne diseases has been documented and is perceived as a common occurrence in South Africa. OBJECTIVES: The main objective of this study was to determine the prevalence of co-infections with Ehrlichia canis or Theileria equi in dogs with babesiosis in the Eastern Cape province. There is a lack of data on canine tick-borne disease distribution in this region. Possible associations of population characteristics and haematological and biochemistry measures with a co-infection of E. canis or T. equi in these dogs were also investigated. METHOD: The study population included 150 dogs naturally infected with babesiosis that presented to the Mdantsane State Veterinary Clinic between January 2021 and November 2021. Quantitative polymerase chain reaction was used to confirm the Babesia spp. that the dogs were infected with and to identify co-infections. Association with co-infection for the following parameters were evaluated: sex, breed, age, duration of illness, leukocyte count, band neutrophil count, monocyte count, platelet count, ARC, and serum globulin concentration. Positive and negative predictive values of monocytosis, leukopenia, band neutrophilia, thrombocytopenia, and non-regenerative absolute reticulocyte count for co-infection were also calculated. RESULTS: Babesia rossi was identified in 149/150 samples and B. vogeli in only 1/150 samples. A co-infection prevalence of 2.0% (3/149; 95% CI: 0.4-5.7) with B. rossi and E. canis was found. No other co-infections were reported. No investigated variables showed significant associations with co-infections. Monocytosis, in particular, was not associated with co-infection. CONCLUSION: Co-infection with other tick-borne diseases in dogs with babesiosis is uncommon in the Eastern Cape province. These findings raise the possibility that B. rossi may have a protective effect against other tick-borne diseases.


Assuntos
Babesiose , Coinfecção , Doenças do Cão , Ehrlichiose , Theileria , Theileriose , Animais , Cães , Babesiose/epidemiologia , Babesiose/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/microbiologia , Coinfecção/veterinária , Coinfecção/epidemiologia , Coinfecção/parasitologia , Ehrlichiose/epidemiologia , Ehrlichiose/veterinária , Theileriose/epidemiologia , Theileriose/parasitologia , Prevalência , Feminino , Masculino , África do Sul/epidemiologia , Theileria/isolamento & purificação , Babesia/isolamento & purificação , Ehrlichia canis/isolamento & purificação , Ehrlichia/isolamento & purificação
3.
Front Endocrinol (Lausanne) ; 15: 1422279, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39239092

RESUMO

Type 1 Diabetes (T1D) is a chronic metabolic disease resulting from insulin deficiency due to autoimmune loss of pancreatic ß cells. In addition to ß cell destruction, it is now accepted that ß cell stress and dysfunction, such as senescence, plays a crucial role in the development of the disease. Accumulation of senescent ß cells occurs during development of T1D in humans and contributes to the progression of T1D in the nonobese diabetic (NOD) mouse model. Senescent ß cells are thought to exacerbate the inflammatory response within the islets by production and secretion of senescence-associated secretory phenotype (SASP). Extracellular vesicles (EVs) from ß cells have been shown to carry protein and microRNAs (miRNAs), influencing cellular signaling and may contribute to the development of T1D but it remains to be addressed how senescence impacts ß cell EV cargo. In this minireview, we discuss emerging evidence that EV cargo proteins and miRNAs associated with senescence could contribute to the development of T1D and could suggest potential biomarkers and therapeutic targets for the regulation of SASP and elimination of senescent ß cells in T1D. Future investigation exploring the intricate relationship between ß cell senescence, EVs and miRNAs could pave the way for the development of novel diagnostic techniques and therapeutic interventions.


Assuntos
Senescência Celular , Diabetes Mellitus Tipo 1 , Vesículas Extracelulares , Células Secretoras de Insulina , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Humanos , Vesículas Extracelulares/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Animais , MicroRNAs/metabolismo , MicroRNAs/genética , Fenótipo Secretor Associado à Senescência
4.
Food Waterborne Parasitol ; 36: e00239, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39247629

RESUMO

Trichinellosis, caused by 13 species/subspecies/genotypes in the nematode genus Trichinella, is a worldwide zoonosis. In the United States, trichinellosis was of historical and economic significance because of European restrictions on the import of U.S. pork. Before the advent of effective protective measures, most cases of trichinellosis were derived from consumption of undercooked or inadequately processed, infected pork. Research conducted at the United States Department of Agriculture (USDA) since 1891, and policies established by USDA regulatory agencies, have helped to reduce Trichinella infections in commercially raised domestic pigs to negligible levels. Here, we review the history of this scientific progress, placing special emphasis on research conducted at the USDA's Beltsville Agricultural Research Center.

5.
Pathogens ; 13(9)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39338923

RESUMO

We used whole genome sequencing (WGS) as an epidemiologic surveillance tool to elucidate the transmission dynamics of Shiga toxin-producing Escherichia coli (STEC) strains along the beef production chain in South Africa. Isolates were obtained from a cattle farm, abattoirs and retail outlets. Isolates were analysed using WGS on a MiSeq platform (Illumina, San Diego, CA, USA) and phylogenetic analysis was carried out. Of the 85 isolates, 39% (33) carried the stx gene and 61% (52) had lost the stx gene. The prevalence of stx subtypes was as follows; stx1a 55% (18/33), stx1b 52% (17/33), stx2a 55% (18/33), stx2b 27% (9/33), stx2dB 30% (10/33) and stx2d1A 15% (5/33). Thirty-five different serogenotypes were detected, of which 65% (56) were flagellar H-antigens and 34% (29) were both O-antigens and flagellar H-antigens. We identified 50 different sequence types (STs), and only nine of the isolates were assigned to three different clonal complexes. Core genome phylogenetic analysis revealed genetic relatedness, and isolates clustered mainly according to their STs and serogenotypes regardless of stx subtypes. This study provides evidence of horizontal transmission and recirculation of STEC strains in Gauteng province and demonstrates that every stage of the beef production chain plays a significant role in STEC entry into the food chain.

6.
Am Heart J ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39313104

RESUMO

BACKGROUND: The Low Dose Colchicine 2 (LoDoCo2) trial randomized 5,522 patients with chronic coronary disease to colchicine 0.5mg daily or placebo in a 1:1 ratio and demonstrated the cardiovascular benefits of colchicine. In the trial, which was conducted in Australia and The Netherlands, a prespecified subgroup analysis suggested a difference in magnitude of treatment effect of colchicine by region (Australia: HR 0.51; 95% CI 0.39-0.67 vs The Netherlands: HR 0.92; 95% CI 0.71-1.20). The aim of this study was to explore possible explanations for the apparent difference in magnitude of treatment effect of colchicine by region in the LoDoCo2 trial. METHODS: The analysis explored potential determinants of variations in the magnitude of effectiveness of colchicine treatment across the regions. This included investigating differences in investigational product, clinical characteristics, concurrent medical therapies and the duration of follow-up using a range of statistical techniques, including sub-group, landmark and effect modification analyses. RESULTS: No differences were found in the colchicine product used in each region. Despite minor differences observed in baseline clinical characteristics and concomitant therapies, the effect modifier analyses demonstrated that these factors did not explain the difference in magnitude of treatment effect of colchicine by region. Randomization in Australia began more than two years before The Netherlands, with shorter duration of follow-up in The Netherlands compared to Australia. In a landmark analysis, over the period when more than 90% of patients in each region had been followed, the effects of colchicine were similar (Australia hazard ratio [HR] 0.58 95% CI 0.34-0.97 vs The Netherlands HR 0.67 95% CI 0.47-0.96). CONCLUSIONS: After examining several plausible explanations for the observed differences in the magnitude of treatment effect of colchicine between regions in the LoDoCo2 trial could be due to the differences in duration of follow-up but a substantial portion of the differences remain unexplained. CLINICAL TRIAL REGISTRATION: https://www.anzctr.org.au/ACTRN12614000093684.

7.
Parasitol Res ; 123(8): 298, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141116

RESUMO

Bovine neosporosis is a widespread parasitic disease associated with significant economic losses. Its effects on the reproductive performance of cows have resulted in losses that run into the hundreds of millions of US dollars in dairy industries in various countries (Reichel et al., Int J Parasitol 43:133-142, 2013). Due to outdated and scant information on the occurrence of Neospora caninum infection in South Africa, the study aimed to determine the seroprevalence and risk factors associated with infection in dairy cattle in South Africa. A total of 1401 blood samples were randomly collected from cattle on 48 dairy farms in seven of the nine provinces in South Africa. A close-ended questionnaire was used in a cross-sectional study to obtain farm-level and animal-level data. Serological testing was done using a commercial IDvet Screen® Neospora caninum Indirect ELISA. An overall seroprevalence, adjusted for test sensitivity and specificity, of 2.3% (95% CI, 1.3-4.1) was detected and 48% (23/48) of sampled farms had at least one animal testing positive. The highest seroprevalence of N. caninum was in the KwaZulu-Natal province with 7.5% (95% CI, 3.8-14.3), and the lowest in Western Cape with 0.1% (95% CI, 0-1.2). The highest within-farm seroprevalence of 25% was detected on a farm in the North West Province. In a multivariable logistic regression model, the odds of N. caninum seropositivity were higher in Holstein-Friesian cattle when compared to other breeds. Good hygiene was identified as a protective factor. Cattle left out on pasture had increased odds of testing positive for N. caninum compared to those that were penned. The odds of testing seropositive for N. caninum was higher on farms that practised segregation of cattle into different age groups. The purchase of replacement animals was a significant risk factor, as open herds had increased odds of N. caninum seropositivity. Cattle on farms that did not have a specific calving location were more likely to be seropositive. This is the first such study in South Africa and shows that N. caninum is widely distributed in the country at a low seroprevalence, but it may be a cause of concern on certain farms.


Assuntos
Anticorpos Antiprotozoários , Doenças dos Bovinos , Coccidiose , Neospora , Animais , Bovinos , Coccidiose/epidemiologia , Coccidiose/veterinária , Coccidiose/parasitologia , África do Sul/epidemiologia , Estudos Soroepidemiológicos , Neospora/imunologia , Neospora/isolamento & purificação , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Fatores de Risco , Estudos Transversais , Anticorpos Antiprotozoários/sangue , Feminino , Ensaio de Imunoadsorção Enzimática/veterinária , Indústria de Laticínios , Inquéritos e Questionários
8.
Cardiovasc Res ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189611

RESUMO

BACKGROUND: Low-dose colchicine reduces the risk of cardiovascular events after myocardial infarction (MI). The purpose of this study was to assess the effect of colchicine post-MI on coronary plaque morphology in non-culprit segments by optical coherence tomography (OCT). METHODS AND RESULTS: COCOMO-ACS was a double-blind, placebo-controlled trial that randomized 64 patients (median age 61.5 years; 9.4% female) with acute non-ST-segment elevation MI to colchicine 0.5 mg daily or placebo for a median of 17.8 months in addition to guideline-recommended therapy. Participants underwent serial OCT imaging within a matched segment of non-culprit coronary artery which contained at least one lipid-rich plaque causing ≥20% stenosis. The primary outcome was the change in minimum fibrous cap thickness (FCT) in non-culprit segments from baseline to final visit. Of those randomized, 57 (29 placebo, 28 colchicine) had evaluable imaging at baseline and follow-up. Overall, colchicine had no effect on relative (placebo +48.0±35.1% vs. colchicine +62.4±38.1%, P=0.18) or absolute changes in minimum FCT (+29.2±20.9 µm vs. +37.2±21.3 µm, P=0.18), or change in maximum lipid arc (-38.8±32.2° vs. -54.8±46.9°, P=0.18) throughout the imaged non-culprit segment. However, in patients assigned colchicine, cap rupture was less frequent (placebo 27.6% vs. colchicine 3.6%, P=0.03). In post-hoc analysis of 43 participants who had been followed for at least 16 months, minimum FCT increased to a greater extent in the colchicine group (placebo +38.7±25.4% vs. colchicine +64.7±34.1%, P=0.005). CONCLUSION: In this study, OCT failed to detect an effect of colchicine on the minimum FCT or maximum lipid arc of plaques in non-culprit segments post-MI. The post-hoc observation that minimum FCT increased to a greater extent with colchicine after more prolonged treatment suggests longer-term studies may be required to detect the effect of anti-inflammatory therapies on plaque morphology by OCT. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Identifier, ACTRN12618000809235, registered on the 11th of May 2018.

9.
BMJ Open ; 14(8): e090233, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39174058

RESUMO

INTRODUCTION: Recurrent patellar dislocation is a debilitating musculoskeletal condition, affecting mainly adolescents and adults under the age of 30. It can persist for many decades, causing pain and cartilage and soft-tissue damage, potentially leading to osteoarthritis. Recurrent patellar dislocation can be managed with physiotherapy or surgery. However, it is not known which treatment is most effective. METHODS AND ANALYSIS: Recurrent Patellar Dislocation: Personalised Therapy or Operative Treatment (REPPORT) is a pragmatic, multicentre, two-arm, superiority, randomised controlled trial. It will compare the clinical and cost-effectiveness of an initial management strategy of personalised, phased and progressive rehabilitation, termed personalised knee therapy versus surgery for recurrent patellar dislocation.The trial's target sample size is 276 participants who will be recruited from approximately 20 sites across the UK. Participants will be randomly allocated to the two treatment groups via a central computer-based minimisation system. Treatment allocation will be in a 1:1 ratio, stratified by age, presence of patella alta and recruitment site.The primary outcome is participant-reported function using the Knee injury and Osteoarthritis Outcome 4-domain score at 18 months post randomisation. Health economic evaluation will be conducted from a healthcare system and personal social services perspective. Secondary outcome data including patellar instability, health utility, work/education status, satisfaction with social roles and treatment, health resource use and adverse events will be collected at 6, 12, 18 and 24 months. Analysis will be on an intention-to-treat basis and reported in-line with the Consolidated Standards of Reporting Trials statement. ETHICS AND DISSEMINATION: The trial was approved by the East Midlands-Nottingham 2 Research Ethics Committee on 30 March 2023.Results will be disseminated via peer-reviewed publications, presentations at national and international conferences, in lay summaries, and using the REPPORT website and social media channels. TRIAL REGISTRATION NUMBER: ISRCTN17972668.


Assuntos
Análise Custo-Benefício , Luxação Patelar , Recidiva , Humanos , Luxação Patelar/cirurgia , Luxação Patelar/terapia , Adulto , Ensaios Clínicos Pragmáticos como Assunto , Adolescente , Modalidades de Fisioterapia , Estudos Multicêntricos como Assunto , Adulto Jovem
10.
Proc Natl Acad Sci U S A ; 121(33): e2405836121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39116128

RESUMO

The 2011 discovery of the first rare earth-dependent enzyme in methylotrophic Methylobacterium extorquens AM1 prompted intensive research toward understanding the unique chemistry at play in these systems. This enzyme, an alcohol dehydrogenase (ADH), features a La3+ ion closely associated with redox-active coenzyme pyrroloquinoline quinone (PQQ) and is structurally homologous to the Ca2+-dependent ADH from the same organism. AM1 also produces a periplasmic PQQ-binding protein, PqqT, which we have now structurally characterized to 1.46-Å resolution by X-ray diffraction. This crystal structure reveals a Lys residue hydrogen-bonded to PQQ at the site analogously occupied by a Lewis acidic cation in ADH. Accordingly, we prepared K142A- and K142D-PqqT variants to assess the relevance of this site toward metal binding. Isothermal titration calorimetry experiments and titrations monitored by UV-Vis absorption and emission spectroscopies support that K142D-PqqT binds tightly (Kd = 0.6 ± 0.2 µM) to La3+ in the presence of bound PQQ and produces spectral signatures consistent with those of ADH enzymes. These spectral signatures are not observed for WT- or K142A-variants or upon addition of Ca2+ to PQQ ⸦ K142D-PqqT. Addition of benzyl alcohol to La3+-bound PQQ ⸦ K142D-PqqT (but not Ca2+-bound PQQ ⸦ K142D-PqqT, or La3+-bound PQQ ⸦ WT-PqqT) produces spectroscopic changes associated with PQQ reduction, and chemical trapping experiments reveal the production of benzaldehyde, supporting ADH activity. By creating a metal binding site that mimics native ADH enzymes, we present a rare earth-dependent artificial metalloenzyme primed for future mechanistic, biocatalytic, and biosensing applications.


Assuntos
Methylobacterium extorquens , Methylobacterium extorquens/enzimologia , Methylobacterium extorquens/metabolismo , Metaloproteínas/química , Metaloproteínas/metabolismo , Álcool Desidrogenase/metabolismo , Álcool Desidrogenase/química , Cristalografia por Raios X , Cofator PQQ/metabolismo , Cofator PQQ/química , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Metais Terras Raras/química , Metais Terras Raras/metabolismo , Modelos Moleculares , Lantânio/química , Lantânio/metabolismo
11.
Parasit Vectors ; 17(1): 341, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138532

RESUMO

BACKGROUND: Rift Valley fever virus (RVFV) is a zoonotic mosquito-borne virus with serious implications for livestock health, human health, and the economy in Africa, and is suspected to be endemic in north-eastern KwaZulu-Natal (KZN), South Africa. The vectors of RVFV in this area are poorly known, although several species, such as Aedes (Neomelaniconion) mcintoshi, Aedes (Neomelaniconion) circumluteolus, Aedes (Aedimorphus) durbanensis, and Culex (Lasioconops) poicilipes may be involved. The aim of the study was to determine the vertebrate blood meal sources of potential RVFV mosquito vectors in north-eastern KZN and to characterize the host-biting network. METHODS: Blood-fed mosquitoes were collected monthly from November 2019 to February 2023 using a backpack aspirator, CO2-baited Centers for Disease Control and Prevention (CDC) miniature light traps and tent traps, in the vicinity of water bodies and livestock farming households. The mosquitoes were morphologically identified. DNA was extracted from individual mosquitoes and used as templates to amplify the vertebrate cytochrome c oxidase I (COI) and cytochrome b (cytb) genes using conventional polymerase chain reaction (PCR). Amplicons were sequenced and queried in GenBank and the Barcode of Life Data systems to identify the vertebrate blood meal sources and confirm mosquito identifications. All mosquitoes were screened for RVFV using real time reverse transcription (RT)-PCR. RESULTS: We identified the mammalian (88.8%) and avian (11.3%) blood meal sources from 409 blood-fed mosquitoes. Aedes circumluteolus (n = 128) made up the largest proportion of collected mosquitoes. Cattle (n = 195) and nyala (n = 61) were the most frequent domestic and wild hosts, respectively. Bipartite network analysis showed that the rural network consisted of more host-biting interactions than the reserve network. All mosquitoes tested negative for RVFV. CONCLUSIONS: Several mosquito species, including Ae. circumluteolus, and vertebrate host species, including cattle and nyala, could play a central role in RVFV transmission. Future research in this region should focus on these species to better understand RVFV amplification.


Assuntos
Aedes , Mosquitos Vetores , Febre do Vale de Rift , Vírus da Febre do Vale do Rift , Animais , África do Sul , Mosquitos Vetores/virologia , Mosquitos Vetores/fisiologia , Vírus da Febre do Vale do Rift/genética , Vírus da Febre do Vale do Rift/isolamento & purificação , Vírus da Febre do Vale do Rift/fisiologia , Febre do Vale de Rift/transmissão , Febre do Vale de Rift/virologia , Febre do Vale de Rift/epidemiologia , Aedes/virologia , Aedes/fisiologia , Aedes/genética , Aedes/classificação , Humanos , Comportamento Alimentar , Culex/virologia , Culex/fisiologia , Mordeduras e Picadas de Insetos , Feminino , Culicidae/virologia , Culicidae/fisiologia , Culicidae/classificação
12.
Am J Physiol Endocrinol Metab ; 327(4): E552-E562, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39196800

RESUMO

Type 1 diabetes (T1D) is a chronic metabolic disease resulting from an autoimmune destruction of pancreatic beta cells. Beta cells activate various stress responses during the development of T1D, including senescence, which involves cell cycle arrest, prosurvival signaling, and a proinflammatory secretome termed the senescence-associated secretory phenotype (SASP). We previously identified growth and differentiation factor 15 (GDF15) as a major SASP factor in human islets and human EndoC-ßH5 beta cells in a model of DNA damage-mediated senescence that recapitulates features of senescent beta cells in T1D. Soluble GDF15 has been shown to exert protective effects on human and mouse beta cells during various forms of stress relevant to T1D; therefore, we hypothesized that secreted GDF15 may play a prosurvival role during DNA damage-mediated senescence in human beta cells. We found that elevated GDF15 secretion was associated with endogenous senescent beta cells in an islet preparation from a T1D donor, supporting the validity of our DNA damage model. Using antibody-based neutralization, we found that secreted endogenous GDF15 was not required for senescent human islet or EndoC cell viability. Rather, neutralization of GDF15 led to reduced expression of specific senescence-associated genes, including GDF15 itself and the prosurvival gene BCL2-like protein 1 (BCL2L1). Taken together, these data suggest that SASP factor GDF15 is not required to sustain senescent human islet viability, but it is required to maintain senescence-associated transcriptional responses.NEW & NOTEWORTHY Beta cell senescence is an emerging contributor to the pathogenesis of type 1 diabetes, but candidate therapeutic targets have not been identified in human beta cells. In this study, we examined the role of a secreted factor, GDF15, and found that although it is not required to maintain viability during senescence, it is required to fine-tune gene expression programs involved in the senescence response during DNA damage in human beta cells.


Assuntos
Senescência Celular , Dano ao DNA , Diabetes Mellitus Tipo 1 , Fator 15 de Diferenciação de Crescimento , Células Secretoras de Insulina , Fator 15 de Diferenciação de Crescimento/metabolismo , Fator 15 de Diferenciação de Crescimento/genética , Humanos , Células Secretoras de Insulina/metabolismo , Senescência Celular/genética , Senescência Celular/fisiologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/genética , Fenótipo Secretor Associado à Senescência , Células Cultivadas , Sobrevivência Celular , Transcrição Gênica
13.
Artigo em Inglês | MEDLINE | ID: mdl-39038852

RESUMO

Recent years have seen increased recognition for the role of ß-cell stress as a contributing factor to the autoimmune destruction process that ultimately results in symptomatic type 1 diabetes (T1D). Preclinical studies have discovered a variety of stress responses in the ß-cell that occur at presymptomatic stages and contribute to disease progression, but unifying explanations of how these mechanisms operate to promote disease progression remain incomplete. We propose that stressed ß-cells transition into ß-cells expressing inflammatory molecules that provoke an immune response to restore homeostasis by coordinating islet repair and the removal of stressed cells. However, when immune surveillance fails, stressed ß-cells accumulate and contribute to autoimmunity. Therapies directed toward stressed ß-cells to either curb their inflammatory signaling or to eliminate them (essentially doing the job of the failed immune surveillance) are moving from animal models into the clinic with promising initial results, although the understanding of how the immune response is coordinated by stressed ß-cells is not clear. In this article, we discuss ß-cell stress responses implicated in T1D pathogenesis based on evidence from humans and highlight existing knowledge gaps in their mechanisms. Future work in this field is poised to target T1D by simultaneously targeting stressed ß-cells and the failed immune response to halt the progression of autoimmunity and prevent ß-cell destruction.

14.
Ann Plast Surg ; 92(6S Suppl 4): S432-S436, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38857009

RESUMO

BACKGROUND: The Goldilocks breast reconstruction utilizes redundant mastectomy skin flaps to fashion a breast mound; however, there is concern that imbrication of these skin flaps may predispose to fat necrosis and make detection of local breast cancer recurrence more difficult. Goldilocks patients follow a traditional postmastectomy screening pathway that includes clinical examination for locoregional recurrence, but it is unclear if this is sufficient. We evaluate our Goldilocks reconstruction case series to determine rates of diagnostic imaging, biopsy, and locoregional and distant recurrence. METHODS: Sixty-six patients (94 breasts) undergoing Goldilocks breast reconstruction were retrospectively reviewed. Any diagnostic postoperative imaging/biopsies performed and that confirmed local or distant breast cancer recurrence were noted. RESULTS: Average time of follow-up was 45 months. Most patients in this cohort had stage 0 (27.3%) or stage I (40.9%) breast cancer. There were a total of 11 (11.7%) concerning breast masses identified. Seven (7.4%) masses were biopsied, of which 5 were benign and 2 were invasive cancer recurrence. Four masses (4.3%) underwent diagnostic imaging only, all with benign findings. Five patients in this series were found to have either distant disease or a second primary cancer in the nonoperative contralateral breast. CONCLUSIONS: Rates of local recurrence following Goldilocks are not higher than expected after other types of postmastectomy reconstruction. Clinical monitoring successfully detected local recurrence in all affected patients in this series. More definite guidelines around the routine screening of Goldilocks mastectomy patients may aid in early detection of local breast cancer recurrence.


Assuntos
Neoplasias da Mama , Recidiva Local de Neoplasia , Humanos , Feminino , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Mamoplastia/métodos , Idoso , Mastectomia , Seguimentos , Retalhos Cirúrgicos
15.
Vet Parasitol ; : 110220, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38910035

RESUMO

Phylogenetic evidence indicates that free-living nematodes gave rise to parasitic nematodes where parasitism evolved independently at least 15 times. The high level of genetic and biological diversity among parasites dictates an equally high level of diversity in the transition to parasitism. We previously hypothesized that horizontal gene transfer (HGT) played an important role in the evolution of parasitism among early ancestors of Trichinella, mediated by an interplay of ecological and evolutionary pathways that contributed to persistence and diversification. We propose that host selection may have been associated with the metabolism of ammonia and engender a new paradigm whereby the reprogrammed nurse cell is capable of generating cyanate thereby enabling the importance of the Trichinella cyanase in the longevity of the cell. Parasites and parasitism have revealed considerable resilience against a backdrop of climate change and environmental perturbation. Here we provide a putative link between key periods in the evolution of Trichinella and major geological and climatological events dating back 500 million years. A useful lens for exploring such ideas, the Stockholm Paradigm, integrates Ecological Fitting (a foundation for host colonization and diversification), the Oscillation Hypothesis (recurring shifts between trends in generalization and specialization relative to host range), the Geographic Mosaic Theory of Coevolution (microevolutionary co-adaptive processes), and the Taxon Pulse Hypothesis (alternating events of biotic expansion i.e., exploitation in evolutionary and ecological time). Here we examine how one or more of these interactive theories, in a phylogenetic-historical context and in conjunction with HGT, may help explain the scope and depth of diversity among Trichinella genotypes.

16.
J Craniofac Surg ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38810244

RESUMO

Microvascular reconstruction of the scalp is frequently indicated in patients with locally advanced tumors, among other etiologies, in a relatively high-risk, older patient population that often has multiple medical comorbidities. A retrospective analysis was performed on patients undergoing microvascular scalp reconstruction at Emory University Hospital and Grady Memorial Hospital between 2011 and 2021. Patient demographics, wound characteristics, operative details, and complications were recorded. Statistical analysis using univariate and multivariate models was performed. Forty-two patients underwent 45 microvascular scalp reconstructive procedures during the study period. The median age was 63 years. Wounds were predominantly oncologic (n=38, 84.4%) and frequently involved deeper structures [calvarium (n=38, 84.4%), dura (n=17, 37.8%)]. At a median follow-up of 350 days, 33 patients (73.3%) had healed flaps, 9 (20.0%) had wound healing issues but ultimately successful reconstruction, and 3 (6.7%) experienced flap failure. Most patients (n=33, 80.9%) were discharged home or to a rehabilitation facility, while the remaining 8 patients (19.1%) were discharged to hospice or died. The 30-day mortality was 4 patients (8.9%) and the 6-month mortality was 8 patients (20.5%). There was a statistically significant difference in 30-day mortality (P=0.0001) on univariate analysis and 6-month mortality (P=0.003) on both univariate and multivariate analysis for patients >70 years. While age >70 years is a risk factor for mortality in patients undergoing microvascular scalp reconstruction, mortality was commonly related to underlying disease processes rather than complication of surgery. Microvascular reconstruction for scalp defects has a high success rate and can be offered as a palliative procedure for patients with locally advanced cancers, advanced age, and multiple comorbidities.

17.
Health Sci Rep ; 7(5): e2090, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38736473

RESUMO

Background and Aim: Goiter is a major source of morbidity in the world, especially in the developing world, where dietary iodine deficiency, a known cause of this condition, is endemic. The diagnosis is mostly by ultrasonography (USG) scan, which can give anatomical, pathological, and functional information for the management of goiter. This study aimed to determine the commonest ultrasound findings of goiter in Ghana. Method: The records of all 213 patients with goiter diagnosed by USG scan over a 5-year period were retrieved. Data collected were sociodemographics, ultrasound features, thyroid nodules diameter, and Thyroid Imaging Reporting and Data System (TI-RADS) scores, which were analyzed using GNU PSPP, version 1.2.0-3. χ 2 and two-tailed independent samples t-test were also employed, with p ≤ 0.05. Results: A total of 213 patients with goiter diagnosed by USG scan were obtained over the study period. The mean age of the participants was 50.01 ± 17.27 years, with an age range of 16-92 years and females constituting the majority (82.16%). The commonest ultrasound features were well-defined solid nodules. The lesion sites for most patients were the whole thyroid (28.17%), both lobes (24.41%), and the right lobe (20.19%). The mean difference in sizes of cysts and solid nodules among genders was 0.26 (CI: -0.14 to 0.67, p = 0.20) and 0.12 (CI: -0.43 to 0.66, p = 0.67), respectively. The TI-RADS score featured TI-RADS 4 (36.62%), TI-RADS 1 (28.17%), TI-RADS 3 (25.82%), TI-RADS 5 (5.16%), and TI-RADS 2 (4.23%). Solid nodules (49.32%, p = 0.001) and cysts (35.71%, p = 0.003) were more common within 41-60 years and less frequent in those <21 years. A p ≤ 0.05 was considered significant in this study. Conclusion: The predominant ultrasound features were well-defined solid nodules, simple cysts, and solid nodules with cystic changes, mostly located in the entire thyroid gland and least located in the isthmus only. Cysts and solid nodules were mostly seen in the 41-60 years age group.

18.
J Phys Chem B ; 128(14): 3383-3397, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38563384

RESUMO

Dehaloperoxidase (DHP) is a multifunctional hemeprotein with a functional switch generally regulated by the chemical class of the substrate. Its two isoforms, DHP-A and DHP-B, differ by only five amino acids and have an almost identical protein fold. However, the catalytic efficiency of DHP-B for oxidation by a peroxidase mechanism ranges from 2- to 6-fold greater than that of DHP-A depending on the conditions. X-ray crystallography has shown that many substrates and ligands have nearly identical binding in the two isoenzymes, suggesting that the difference in catalytic efficiency could be due to differences in the conformational dynamics. We compared the backbone dynamics of the DHP isoenzymes at pH 7 through heteronuclear relaxation dynamics at 11.75, 16.45, and 19.97 T in combination with four 300 ns MD simulations. While the overall dynamics of the isoenzymes are similar, there are specific local differences in functional regions of each protein. In DHP-A, Phe35 undergoes a slow chemical exchange between two conformational states likely coupled to a swinging motion of Tyr34. Moreover, Asn37 undergoes fast chemical exchange in DHP-A. Given that Phe35 and Asn37 are adjacent to Tyr34 and Tyr38, it is possible that their dynamics modulate the formation and migration of the active tyrosyl radicals in DHP-A at pH 7. Another significant difference is that both distal and proximal histidines have a 15-18% smaller S2 value in DHP-B, thus their greater flexibility could account for the higher catalytic activity. The distal histidine grants substrate access to the distal pocket. The greater flexibility of the proximal histidine could also accelerate H2O2 activation at the heme Fe by increased coupling of an amino acid charge relay to stabilize the ferryl Fe(IV) oxidation state in a Poulos-Kraut "push-pull"-type peroxidase mechanism.


Assuntos
Histidina , Poliquetos , Animais , Histidina/química , Isoenzimas/metabolismo , Peróxido de Hidrogênio/metabolismo , Hemoglobinas/química , Peroxidases/química , Peroxidase/química , Poliquetos/química , Poliquetos/metabolismo , Cristalografia por Raios X
19.
STAR Protoc ; 5(1): 102923, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38427571

RESUMO

A subpopulation of pancreatic beta cells becomes senescent during type 1 diabetes (T1D) progression, and removal of these populations protects against T1D in mice. Here, we present a protocol to measure senescence in murine pancreatic islet cells through analysis of senescence-associated ß-galactosidase activity. We describe steps for staining with the fluorogenic substrate C12FDG and analysis by flow cytometry. Increased cell size is another marker of senescence and can also be concurrently measured in the same experiment. For complete details on the use and execution of this protocol, please refer to Lee et al.1 and Helman et al.2.


Assuntos
Senescência Celular , Diabetes Mellitus Tipo 1 , Camundongos , Animais , beta-Galactosidase , Células Epiteliais , Modelos Animais de Doenças
20.
Artigo em Inglês | MEDLINE | ID: mdl-38486357

RESUMO

AIMS: Recent trials have shown that low-dose colchicine (0.5 mg once daily) reduces major cardiovascular events in patients with acute and chronic coronary syndromes. We aimed to estimate the cost-effectiveness of low-dose colchicine therapy in patients with chronic coronary disease when added to standard background therapy. METHODS AND RESULTS: This Markov cohort cost-effectiveness model used estimates of therapy effectiveness, transition probabilities, costs and quality of life obtained from the Low-dose Colchicine 2 (LoDoCo2) trial, as well as meta-analyses and public sources. In this trial, Low-dose colchicine was added to standard of care and compared to placebo. The main outcomes were cardiovascular events including myocardial infarction, stroke and coronary revascularisation, quality-adjusted life-year (QALY), the cost per QALY gained (incremental cost-effectiveness ratio), and net monetary benefit. In the model, low-dose colchicine therapy yielded 0.04 additional QALYs compared with standard of care at an incremental cost of €455 from a societal perspective and €729 from a healthcare perspective, resulting in a cost per QALY gained of €12,176/QALY from a societal perspective and €19,499/QALY from a healthcare perspective. Net monetary benefit was €1,414 from a societal perspective and €1,140 from a healthcare perspective. Low-dose colchicine has a 96% and 94% chance of being cost effective, from respectively a societal and healthcare perspective when using a willingness to pay of €50,000/QALY. Net monetary benefit would decrease below zero when annual low-dose colchicine costs would exceed an annual cost of €221 per patient. CONCLUSION: Adding low-dose colchicine to standard of care in patients with chronic coronary disease is cost-effective according to commonly accepted thresholds in Europe and Australia and compares favourably in cost-effectiveness to other drugs used in chronic coronary disease.

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