Canadian Association of Thoracic Surgeons

The survey examined differences in calving distribution, calf management, feed and water testing, and animal health practices among cow–calf herds in western and eastern Canada, using data from the 2022 breeding season through weaning of the 2023 calf crop. Larger herds had a higher proportion of cows (63%) and heifers (67%) calving in the first 21 days compared to smaller herds (57% and 63%, respectively). Pain control for dehorning was more commonly reported in the east (82%) than the west (67%), though overall frequency of use did not differ significantly. For castration, pain control use was slightly higher in the west (50%) than in the east (45%), with a significant regional difference in frequency ( P = 0.013). Feed testing varied by region ( P < 0.001), occurring once or more annually in 50% of western and 31% of eastern herds. Water testing frequency did not differ significantly, with over 60% of producers in both regions never testing water. Vaccination rates were 95% (west) and 92% (east). While vaccination and pain control uptake was consistently high overall, there is room to improve pre-breeding vaccine use, pain control, and feed and water testing—especially among smaller herds or those relying on visual assessments for cattle performance.

BackgroundPeople who inject drugs are disproportionately affected by HIV and hepatitis C infections. Estimating the size and distribution of this population is essential in monitoring infectious diseases rates and progress towards elimination.ObjectiveThis study aims to estimate the population sizes of people in Canada who have ever injected drugs, stratified by sex (assigned at birth), province/region and steroid injection, and those who have recently injected drugs (past 12 months), stratified by sex and steroid injection. While a previous national study reported estimates of recent injection by province, this study provides the first estimates of people who have ever injected drugs at both the national and provincial/regional levels. It is also the first to incorporate stratification by sex and steroid injection, using the most currently available data.MethodsUsing combined cycles (2017–2021) of the Canadian Community Health Survey (CCHS), a nationally representative population-based survey, we applied the weighted prevalence of injection drug use to the 2021 Statistics Canada national population size estimate of individuals aged 15 years or more. To this, further adjustments were made using additional data to account for populations not sampled in the CCHS and under-reporting of injection drug use in surveys.ResultsIn 2021, an estimated 388,400 (95% CI: 338,900–436,500) people in Canada had ever injected drugs, representing 1.22% of the Canadian population 15 years of age and older. Among these, 75% were male and 25% were female. These estimates varied across regions, ranging from 0.92% to 2.47%. The estimated number of people who have recently injected drugs was 100,300 (95% CI: 82,300–119,200) or 0.31% of the population, of which 74% were male and 26% were female.ConclusionEstimates of people who inject drugs at the national and provincial/regional levels can be used to track key epidemiological metrics that inform public health policy and programming.

This study provides an update to a landmark 2004 report describing demographics, training, and trends in adherence to thoracic surgery practice standards in Canada. An updated questionnaire was administered to all members of the Canadian Association of Thoracic Surgeons via email (n=142, compared to n=68 in 2004). Our report incorporates internal data from Ontario Health and the Canadian Partnership Against Cancer. Forty-eight surgeons completed the survey (male, 70.8%; mean±standard deviation age, 50.3±9.3 years). This represents a 33.8% response rate, compared to 64.7% in 2004. Most surgeons (69%) served a patient population of over 1 million per center; 32%-34% reported an on-call ratio of 1:4-1:5 days, and the average weekly hours worked was 56.4±11.9. Greater access to dedicated geographic units per center (73% in 2021 vs. 53% in 2004) has improved thoracic-associated services and house staff, notably endoscopy units (100% vs. 91%), with 73% of respondents having access to both endobronchial and endoscopic ultrasound. Access to thoracic radiology has also improved, particularly regarding positron emission tomography scanners per center (76.9% vs. 13%). Annual case volumes for lung (255 vs. 128), esophageal (41 vs. 19), and mediastinal resections (30 vs. 13), along with hiatal hernia repair (45 vs. 20), have increased substantially despite reports of operating room availability and radiology as rate-limiting steps. This survey characterizes compliance with current practice standards, addressing the needs of thoracic surgeons across Canada. Over 85% of respondents were aware of the 2004 compliance paper, and 35% had applied for resources and equipment in response.

SummaryThis study investigated the possibility of transforming unsalted pork hydrolysate into a liquid seasoning by studying volatile compound production through yeast fermentation. The yeasts used included a typical soya sauce yeast and three wine yeasts. The yeasts inoculated in the glucose supplementary pork hydrolysate increased by approximately 2.0 log of CFU mL−1 within 24 hours at 30°C without adding salt. Yeast fermentation largely depleted the abundant aldehydes (hexenal) present in unfermented pork hydrolysate to trace levels with the formation of ethanol, corresponding alcohols and carboxylic acids. The wine yeasts showed higher production of fruity esters such as ethyl acetate and isoamyl acetate, whereas the soya sauce yeast produced more ketones such as acetone and 2‐heptanone. This study revealed a potential method of producing a value‐added meat hydrolysate from pork by‐product.

The persistence of donor cells derived from the graft (chimerism) has been documented in various tissues after organ transplantation. It was suggested that stable chimerism might reflect a state of donor-specific tolerance. Chimerism of macrophages and lymphocytes were studied over time after lung transplantation as well as its impact on graft tolerance. Macrophages and lymphocytes were purified from bronchoalveolar lavage sequentially obtained from 24 patients between 1 and 41 months posttransplantation (20, 22, 24, and 17 patients at, respectively, 1, 3, 6, and 12 months). DNA was extracted from these cells and their recipient-donor origin was evaluated by PCR amplification of highly polymorphic DNA regions (minisatellites). We show that the remaining donor cells over the first month vary from 10 up to 50% and 5 up to 55% for lymphocytes and macrophages respectively (+/-2 SD). All patients presented some chimerism up to the 6th postoperative month. Good correlation was observed between the residual amount of donor lymphocytes and macrophages during the first 3 months (P<0.001). Patients with at least 30% donor lymphocytes at 1 month after transplantation had less rejections (> or =stage II) in the follow up (P=0.0007). The same observation is true for donor macrophages although to lower extend (P=0.02). The chimerism lost its predictive value beyond 3 months. These data demonstrate that a level of chimerism above 30% of either donor lymphocytes or macrophages at 1 month is related to a better state of graft tolerance. However, chimerism decreases markedly beyond 3 months and has then no predictive value.

Flow cytometry crossmatching (FCXM) is more sensitive than the cytotoxic crossmatch in identifying preformed antibodies to donor alloantigens, but its clinical importance is controversial. The objective of this study was to determine the association of a FCXM with survival and incidence of vascular rejection in cardiac transplant recipients with a negative cytotoxic crossmatch. Between 1993 and 1998, 357 heart transplant recipients with a negative T cell cytotoxic crossmatch were studied by three-color FCXM to quantitate anti-donor IgG reactions against B and T lymphocytes. Reactions positive against both were consistent with human leukocyte antigen (HLA) Class I reactivity, and those against B cells only were considered to be against HLA Class II antigens. Endpoints were episodes of vascular rejection, death from acute and chronic rejection and overall survival. Fifty patients were FCXM for Class I-positive, 144 for Class II-positive, and 163 were negative. At 1 month, freedom from vascular rejection was 64% in Class I patients, but 90% and 96% in Class II or negative crossmatch patients (P<0.0001). Survival of the negative crossmatch group was higher than either Class I or II groups (94%, 74% and 76%, respectively, at 3 years; P<0.0001). Death from acute rejection was 3% and 2% at 3 years in negative or Class II-positive patients, but 19% in Class I patients (P<0.0001). Death from chronic rejection occurred only in Class II patients (P=0.002). Despite a negative T-cell cytotoxic crossmatch, a positive flow cytometry crossmatch correlates with important clinical events after heart transplantation.

We investigate the persistence probability in the Voter model for dimensions d\geq 2. This is achieved by mapping the Voter model onto a continuum reaction-diffusion system. Using path integral methods, we compute the persistence probability r(q,t), where q is the number of ``opinions'' in the original Voter model. We find r(q,t)\sim exp[-f_2(q)(ln t)^2] in d=2; r(q,t)\sim exp[-f_d(q)t^{(d-2)/2}] for 2<d<4; r(q,t)\sim exp[-f_4(q)t/ln t] in d=4; and r(q,t)\sim exp[-f_d(q)t] for d>4. The results of our analysis are checked by Monte Carlo simulations.