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1.
Vet Pathol ; 60(1): 88-100, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36112824

RESUMO

Outbreaks of humeral fractures in dairy cows have been reported in New Zealand for several years. Gross, histologic, and histomorphometric findings in the humerus from primiparous cows with spontaneous humeral fracture were compared to age-matched control cows. Affected cows had a complete nonarticular spiral fracture of the humerus. Histologically affected humeri had a thicker growth plate with abnormal architecture, thinner cortex with increased abnormal resorption, increased resorption in the distal humerus, decreased trabecular density, abnormal trabecular architecture, presence of growth arrest lines and woven bone formation. Histomorphometry showed reduction in bone volume, trabecular perimeter, and trabecular width. Cows grazed on fodder beet had thicker growth plates with an abnormal appearance compared with cows grazed on pasture, and cows with low/marginal liver copper concentration had more resorption cavities in the distal humerus and thinner cortical bone compared with cows with adequate liver copper concentration. Decreased trabecular density (OR = 249.5), abnormal cortical resorption (OR = 54.2), presence of woven bone formation in the proximal metaphysis (OR = 37.2), and the number of resorption cavities in the distal humerus were significantly associated with a high probability of fracture. Ribs had enlargement of the costochondral junction with fractures in different stages of healing. Histology of the ribs revealed abnormal growth plate appearance, presence of fracture lines, callus tissue, fibrosis, and microfractures. Cows with humeral fracture have osteoporosis due to decreased bone formation and increased bone resorption, likely associated with inadequate feed quality and perhaps copper deficiency leading to a reduction in bone strength and fracture.


Assuntos
Doenças dos Bovinos , Fraturas do Úmero , Osteoporose , Feminino , Bovinos , Animais , Nova Zelândia/epidemiologia , Cobre , Fraturas do Úmero/veterinária , Fraturas do Úmero/complicações , Fraturas do Úmero/patologia , Úmero , Osteoporose/veterinária , Osteoporose/complicações , Osteoporose/epidemiologia , Doenças dos Bovinos/patologia
2.
Emerg Infect Dis ; 28(12): 2491-2499, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36417938

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tickborne bandavirus mainly transmitted by Haemaphysalis longicornis ticks in East Asia, mostly in rural areas. As of April 2022, the amplifying host involved in the natural transmission of SFTSV remained unidentified. Our epidemiologic field survey conducted in endemic areas in China showed that hedgehogs were widely distributed, had heavy tick infestations, and had high SFTSV seroprevalence and RNA prevalence. After experimental infection of Erinaceus amurensis and Atelerix albiventris hedgehogs with SFTSV, we detected robust but transitory viremias that lasted for 9-11 days. We completed the SFTSV transmission cycle between hedgehogs and nymph and adult H. longicornis ticks under laboratory conditions with 100% efficiency. Furthermore, naive H. longicornis ticks could be infected by SFTSV-positive ticks co-feeding on naive hedgehogs; we confirmed transstadial transmission of SFTSV. Our study suggests that the hedgehogs are a notable wildlife amplifying host of SFTSV in China.


Assuntos
Phlebovirus , Febre Grave com Síndrome de Trombocitopenia , Carrapatos , Animais , Ouriços , Estudos Soroepidemiológicos , Filogenia , Phlebovirus/genética , China/epidemiologia
3.
Emerg Infect Dis ; 28(2): 363-372, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35075994

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is spreading rapidly in Asia. This virus is transmitted by the Asian longhorned tick (Haemaphysalis longicornis), which has parthenogenetically and sexually reproducing populations. Parthenogenetic populations were found in ≥15 provinces in China and strongly correlated with the distribution of severe fever with thrombocytopenia syndrome cases. However, distribution of these cases was poorly correlated with the distribution of populations of bisexual ticks. Phylogeographic analysis suggested that the parthenogenetic population spread much faster than bisexual population because colonization is independent of sexual reproduction. A higher proportion of parthenogenetic ticks was collected from migratory birds captured at an SFTSV-endemic area, implicating the contribution to the long-range movement of these ticks in China. The SFTSV susceptibility of parthenogenetic females was similar to that of bisexual females under laboratory conditions. These results suggest that parthenogenetic Asian longhorned ticks, probably transported by migratory birds, play a major role in the rapid spread of SFTSV.


Assuntos
Infecções por Bunyaviridae , Ixodidae , Phlebovirus , Febre Grave com Síndrome de Trombocitopenia , Carrapatos , Animais , Infecções por Bunyaviridae/epidemiologia , Feminino , Phlebovirus/genética , Filogenia
4.
Int J Mol Sci ; 23(9)2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35563508

RESUMO

Post-traumatic OA (PTOA) is often triggered by injurious, high-impact loading events which result in rapid, excessive chondrocyte cell death and a phenotypic shift in residual cells toward a more catabolic state. As such, the identification of a disease-modifying OA drug (DMOAD) that can protect chondrocytes from death following impact injury, and thereby prevent cartilage degradation and progression to PTOA, would offer a novel intervention. We have previously shown that urocortin-1 (Ucn) is an essential endogenous pro-survival factor that protects chondrocytes from OA-associated pro-apoptotic stimuli. Here, using a drop tower PTOA-induction model, we demonstrate the extent of Ucn's chondroprotective role in cartilage explants exposed to excessive impact load. Using pathway-specific agonists and antagonists, we show that Ucn acts to block load-induced intracellular calcium accumulation through blockade of the non-selective cation channel Piezo1 rather than TRPV4. This protective effect is mediated primarily through the Ucn receptor CRF-R1 rather than CRF-R2. Crucially, we demonstrate that the chondroprotective effect of Ucn is maintained whether it is applied pre-impact or post-impact, highlighting the potential of Ucn as a novel DMOAD for the prevention of injurious impact overload-induced PTOA.


Assuntos
Cartilagem Articular , Osteoartrite , Cartilagem Articular/metabolismo , Morte Celular , Condrócitos/metabolismo , Humanos , Canais Iônicos/metabolismo , Osteoartrite/etiologia , Osteoartrite/metabolismo , Urocortinas/metabolismo , Urocortinas/farmacologia
5.
Mol Microbiol ; 108(4): 350-360, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29476656

RESUMO

Polyamines are an essential class of metabolites found throughout all kingdoms in life. Borrelia burgdorferi harbors no enzymes to synthesize or degrade polyamines yet does contain a polyamine uptake system, potABCD. In this report, we describe the initial characterization of this putative transport system. After several unsuccessful attempts to inactivate potABCD, we placed the operon under the control of an inducible LacI promoter expression system. Analyses of this construct confirmed that potABCD was required for in vitro survival. Additionally, we demonstrated that the potABCD operon were upregulated in vitro by low osmolarity. Previously, we had shown that low osmolarity triggers the activation of the Rrp2/RpoN/RpoS regulatory cascade, which regulates genes essential for the transmission of spirochetes from ticks to mammalian hosts. Interestingly, induction of the pot operon was only affected in an rpoS mutant but not in a rpoN mutant, suggesting that the genes were RpoS dependent and RpoN independent. Furthermore, potABCD was upregulated during tick feeding concomitant with the initiation of spirochete replication. Finally, uptake experiments determined the specificity of B. burgdorferi's PotABCD for spermidine.


Assuntos
Proteínas de Bactérias/metabolismo , Borrelia burgdorferi/genética , Proteínas de Transporte/metabolismo , Putrescina/metabolismo , Espermidina/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Sobrevivência Celular/genética , Humanos , Ixodes/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos MRL lpr/microbiologia , Óperon/genética , Concentração Osmolar , Plasmídeos/genética
6.
J Thromb Thrombolysis ; 48(2): 181-186, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31124033

RESUMO

International classification of disease (ICD) codes can improve the efficiency of epidemiological research provided the codes accurately identify outcomes of interest. The purpose of this retrospective cross-sectional study is to evaluate the accuracy of ICD-10 codes for identifying thromboembolic events occurring during anticoagulation therapy. Medical charts of patients hospitalized for any reason while receiving anticoagulant therapy between September 1, 2017 and December 31, 2017 were reviewed by two reviewers blinded to ICD-10 code status. Following identification of confirmed acute thromboembolic events, ICD-10 codes were unblinded and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) along with 95% confidence intervals (CI) were calculated for coding in any diagnosis position ("principal" or "other"). There were 661 hospitalizations identified among 487 anticoagulated patients. There were 27 thromboembolic events identified during chart review. Stroke and venous thromboembolism were the most common thromboembolic event types. Overall thromboembolic ICD-10 coding sensitivity was 100.0% (95% CI 87.2-100.0); specificity was 79.3% (75.9-82.4). PPV was 17.1% (11.6-23.9%), and NPV was 100% (99.3-100.0). ICD-10 codes can reliably be used for ruling out hospitalizations for thromboembolic events in patients receiving anticoagulation therapy but should not be used for identifying thromboembolic complications without confirmatory chart review.


Assuntos
Anticoagulantes/uso terapêutico , Classificação Internacional de Doenças/normas , Tromboembolia Venosa/diagnóstico , Doença Aguda , Idoso , Estudos Transversais , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tromboembolia Venosa/tratamento farmacológico
7.
PLoS Pathog ; 12(8): e1005791, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27525653

RESUMO

Lyme disease, caused by Borrelia burgdorferi, is a vector-borne illness that requires the bacteria to adapt to distinctly different environments in its tick vector and various mammalian hosts. Effective colonization (acquisition phase) of a tick requires the bacteria to adapt to tick midgut physiology. Successful transmission (transmission phase) to a mammal requires the bacteria to sense and respond to the midgut environmental cues and up-regulate key virulence factors before transmission to a new host. Data presented here suggest that one environmental signal that appears to affect both phases of the infective cycle is osmolarity. While constant in the blood, interstitial fluid and tissue of a mammalian host (300 mOsm), osmolarity fluctuates in the midgut of feeding Ixodes scapularis. Measured osmolarity of the blood meal isolated from the midgut of a feeding tick fluctuates from an initial osmolarity of 600 mOsm to blood-like osmolarity of 300 mOsm. After feeding, the midgut osmolarity rebounded to 600 mOsm. Remarkably, these changes affect the two independent regulatory networks that promote acquisition (Hk1-Rrp1) and transmission (Rrp2-RpoN-RpoS) of B. burgdorferi. Increased osmolarity affected morphology and motility of wild-type strains, and lysed Hk1 and Rrp1 mutant strains. At low osmolarity, Borrelia cells express increased levels of RpoN-RpoS-dependent virulence factors (OspC, DbpA) required for the mammalian infection. Our results strongly suggest that osmolarity is an important part of the recognized signals that allow the bacteria to adjust gene expression during the acquisition and transmission phases of the infective cycle of B. burgdorferi.


Assuntos
Adaptação Fisiológica/fisiologia , Borrelia burgdorferi/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Ixodes/parasitologia , Doença de Lyme/transmissão , Animais , Proteínas de Bactérias/biossíntese , Modelos Animais de Doenças , Immunoblotting , Insetos Vetores/parasitologia , Camundongos , Concentração Osmolar , Reação em Cadeia da Polimerase , Virulência/fisiologia , Fatores de Virulência/biossíntese
8.
Data Brief ; 55: 110561, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38966665

RESUMO

Thin plate smoothing spline models, covering Canada and the continental United States, were developed using ANUSPLIN for 30-year (1991-2020) monthly mean maximum and minimum temperature and precipitation. These models employed monthly weather station values from the North American dataset published by National Oceanic and Atmospheric Administration's (NOAA's) National Centers for Environmental Information (NCEI). Maximum temperature mean absolute errors (MAEs) ranged between 0.54 °C and 0.64 °C (approaching measurement error), while minimum temperature MAEs were slightly higher, varying from 0.87 °C to 1.0 °C. On average, thirty-year precipitation estimates were accurate to within approximately 10 % of total precipitation levels, ranging from 9.0 % in the summer to 12.2 % in the winter. Error rates were higher in Canada compared to estimates in the United States, consistent with a less dense station network in Canada relative to the United States. Precipitation estimates in Canada exhibited MAEs representing 14.7 % of mean total precipitation compared to 9.7 % in the United States. The datasets exhibited minimal bias overall; 0.004 °C for maximum temperature, 0.01 °C for minimum temperature, and 0.5 % for precipitation. Winter months showed a greater dry bias (0.8 % of total winter precipitation) compared to other seasons (-0.4 % of precipitation). These 30-year gridded datasets are available at ∼2 km resolution.

9.
Animals (Basel) ; 14(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38338167

RESUMO

A multi-method approach integrating data from four independent sources was used to describe some key features of the epidemiology and estimate the herd and within-herd incidence of fractured humeri in New Zealand dairy cattle for the period 2007-2015. The first dataset was from a national case series where cases of humeral fractures in dairy cattle were identified by veterinarians across New Zealand between the 2007/2008 and 2011/2012 lactation seasons. The second dataset was from a pet food company based in the Waikato region, which collated the number of casualty first- and second-lactation cows found to have a fractured humerus post-slaughter in the 2014/2015 lactation season, and the third dataset was a case series conducted by veterinarians employed in a Waikato veterinary business, also from the 2014/2015 lactation season. For the final dataset, 505 randomly selected New Zealand dairy farmers completed a phone survey on the incidence of non-responsive, non-weight-bearing forelimb lameness in first- and second-lactation cows in the 2014/2015 lactation season. Using the telephone survey results, the within-herd and herd-level incidence of cases for first- and second-lactation dairy animals was calculated. The national case series reported 149 cases of humeral fractures in 22 dairy herds; the pet food case series identified 61 cases from 41 farms; and the practice-based case series found 14 cases from 10 farms. Humeral fractures exclusively affected first- and second-lactation dairy cows and had a peak incidence between calving and early mating. The national telephone survey found that non-weight-bearing forelimb lameness requiring euthanasia of first- or second-lactation cows occurred in 11.7% of herds, with a mean within-herd incidence of 2.6% for first lactation cows and 2.8% for second-lactation cows for affected herds. These combined datasets demonstrate that humeral fractures in young, lactating dairy cattle are more common than previously suspected and that they occur nationally and over multiple years on some farms. Further work on this condition is urgently required in New Zealand to establish cost-effective management practices that will reduce unnecessary animal suffering and waste.

10.
Data Brief ; 49: 109450, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37577738

RESUMO

Heating degree days (HDD) represent a concise measure of heating energy requirements used to inform decision making about the impact of climate change on heating energy demand. This data paper presents spatial datasets of heating degree days (HDD) for Canada for two thirty-year periods, 1951-1980 and 1981-2010, using daily temperature gauge observations over these time periods. Stations with fewer than nine missing days in a year and greater than nine years of data over each thirty-year period were included, resulting in 1339 and 1679 stations for the 1951-1980 and 1981-2010 periods respectively. Mean absolute error (MAE) of the spatial models ranged from 124.2 Celsius degree days (C-days) for the 1951-1980 model (2.4% of the surface mean) to 137.6 C-days for the 1981-2010 model (2.7%). This note presents maps illustrating cross validation errors at a set of representative stations. The grids are available at ∼2 km resolutions.

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