Estimates of genetic parameters for rumination time, feed efficiency, and methane production traits in first lactation Holstein cows.

The large-scale recording of traits such as feed efficiency and methane emissions for use in genetic improvement programs is complex, costly, and time-consuming. Therefore, heritable traits that can be continuously recorded in dairy herds and are correlated to feed efficiency and methane emission traits could provide useful information for genetic evaluation. Rumination time has been suggested to be associated with feed efficiency, methane production (methane emission in g/day), and production traits at the phenotypic level. Therefore, the objective of this study was to investigate the genetic relationships among rumination time, feed efficiency, methane and production traits using 7,358 records from 656 first lactation Holstein cows. The estimated heritabilities were moderate for rumination time (0.45 ± 0.14), methane production (0.36 ± 0.12), milk yield (0.40 ± 0.08), fat yield (0.29 ± 0.06), protein yield (0.32 ± 0.07), and energy corrected milk (0.28 ± 0.07), while low and non-significant for feed efficiency (0.15 ± 0.07), which was defined as the residual of the multiple linear regression of DMI on ECM and MBW. A favorable negative genetic correlation was estimated between rumination time and methane production (-0.53 ± 0.24), while a positive favorable correlation was estimated between rumination time and energy corrected milk (0.49 ± 0.11). The estimated genetic correlation of rumination time with feed efficiency (-0.01 ± 0.17) was not significantly different from zero but showed a trend of a low correlation with dry matter intake (0.21 ± 0.13, P = 0.11). These results indicate that rumination time is genetically associated with methane production and milk production traits, but high standard errors indicate that further analyses should be conducted to verify these findings when more data for rumination time, methane production and feed efficiency become available.

High frequency of endoluminal thrombus in patients with ischaemic stroke following AARS-CoV-2 infection.

BACKGROUND: Ischaemic stroke may be a major complication of SARS-CoV-2 infection. Studying and characterising the different aetiological subtypes, clinical characteristics, and functional outcomes may be valuable in guiding patient selection for optimal management and treatment. METHODS: Data were collected retrospectively on consecutive patients with COVID-19 who developed acute focal brain ischaemia (between 1 March and 19 April 2020) at a tertiary university hospital in Madrid (Spain). RESULTS: During the study period, 1594 patients were diagnosed with COVID-19. We found 22 patients with ischaemic stroke (1.38%), 6 of whom did not meet the inclusion criteria. The remaining 16 patients were included in the study (15 cases of ischaemic stroke and one case of transient ischaemic attack). Median baseline National Institutes of Health Stroke Scale score was 9 (interquartile range: 16), and mean (standard deviation) age was 73 years (12.8). Twelve patients (75%) were men. Mean time from COVID-19 symptom onset to stroke onset was 13 days. Large vessel occlusion was identified in 12 patients (75%). We detected elevated levels of D-dimer in 87.5% of patients and C-reactive protein in 81.2%. The main aetiology was atherothrombotic stroke (9 patients, 56.3%), with the predominant subtype being endoluminal thrombus (5 patients, 31.2%), involving the internal carotid artery in 4 cases and the aortic arch in one. The mortality rate in our series was 44% (7 of 16 patients). CONCLUSIONS: In patients with COVID-19, the most frequent stroke aetiology was atherothrombosis, with a high proportion of endoluminal thrombus (31.2% of patients). Our clinical and laboratory data support COVID-19-associated coagulopathy as a relevant pathophysiological mechanism for ischaemic stroke in these patients.

Machine learning classification of breeding protocol descriptions from Canadian Holsteins.

Dairy farmers are motivated to ensure cows become pregnant in an optimal and timely manner. Although timed artificial insemination (TAI) is a successful management tool in dairy cattle, it masks an animal's innate fertility performance, likely reducing the accuracy of genetic evaluations for fertility traits. Therefore, separating fertility traits based on the recorded management technique involved in the breeding process or adding the breeding protocol as an effect to the model can be viable approaches to address the potential bias caused by such management decisions. Nevertheless, there is a lack of specificity and uniformity in the recording of breeding protocol descriptions by dairy farmers. Therefore, this study investigated the use of 8 supervised machine learning algorithms to classify 1,835 unique breeding protocol descriptions from 981 herds into the following 2 classes: TAI or other than TAI. Our results showed that models that used a stacking classifier algorithm had the highest Matthews correlation coefficient (0.94 ± 0.04, mean ± SD) and maximized precision and recall (F1-score = 0.96 ± 0.03) on test data. Nonetheless, their F1-scores on test data were not different from 5 out of the other 7 algorithms considered. Altogether, results presented herein suggest machine learning algorithms can be used to produce robust models that correctly identify TAI protocols from dairy cattle breeding records, thus opening the opportunity for unbiased genetic evaluation of animals based on their natural fertility.

High frequency of endoluminal thrombus in patients with ischaemic stroke following SARS-CoV-2 infection. / Alta frecuencia de trombo endoluminal en pacientes con ictus isquémico tras la infección por coronavirus 2019.

BACKGROUND: Ischaemic stroke may be a major complication of SARS-CoV-2 infection. Studying and characterising the different aetiological subtypes, clinical characteristics, and functional outcomes may be valuable in guiding patient selection for optimal management and treatment. METHODS: Data were collected retrospectively on consecutive patients with SARS-CoV-2 infection who developed acute focal brain ischaemia (between 1 March and 19 April 2020) at a tertiary university hospital in Madrid (Spain). RESULTS: During the study period, 1594 patients were diagnosed with COVID-19. We found 22 patients with ischaemic stroke (1.38%), 6 of whom did not meet the inclusion criteria. The remaining 16 patients were included in the study (15 cases of ischaemic stroke and one case of transient ischaemic attack). Median baseline National Institutes of Health Stroke Scale score was 9 (interquartile range: 16), and mean (standard deviation) age was 73 years (12.8). Twelve patients (75%) were men. Mean time from COVID-19 symptom onset to stroke onset was 13 days. Large vessel occlusion was identified in 12 patients (75%). We detected elevated levels of D-dimer in 87.5% of patients and C-reactive protein in 81.2%. The main aetiology was atherothrombotic stroke (9 patients, 56.3%), with the predominant subtype being endoluminal thrombus (5 patients, 31.2%), involving the internal carotid artery in 4 cases and the aortic arch in one. The mortality rate in our series was 44% (7 of 16 patients). CONCLUSIONS: In patients with COVID-19, the most frequent stroke aetiology was atherothrombosis, with a high proportion of endoluminal thrombus (31.2% of patients). Our clinical and laboratory data support COVID-19-associated coagulopathy as a relevant pathophysiological mechanism for ischaemic stroke in these patients.

Estimated genetic parameters for all genetically evaluated traits in Canadian Holsteins.

Genetic improvement is a crucial tool to deal with the increasing demand for high quality, sustainably produced dairy. Breeding programs are based on genetic parameters, such as heritability and genetic correlations, for economically important traits in a population. In this study, we estimated population genetic parameters and genetic trends for 67 traits evaluated on heifers and first-lactation Canadian Holstein cows. The data consisted of approximately 500,000 records with pedigree information collected from 1980 to 2019. Genetic parameters were estimated using bivariate linear animal models under a Bayesian approach. Analyses for the 67 traits resulted in 2,211 bivariate combinations, from which the estimated genetic parameters are reported here. The most highly heritable traits were fat percent (0.66) and protein percent (0.69), followed by stature (0.47). Lowest heritabilities (0.01) were observed for disease-related traits, such as lameness and toe ulcer, and calf survival. The genetic correlations between gestation length, calf size, and calving ease measured on both heifer and cows were close to unity. On the other hand, traits such as body condition score and pin width, cystic ovaries and sole ulcer, rear teat placement, and toe ulcer were genetically unrelated. This study reports genetic parameters that have not been previously published for Canadian Holstein cows, and provides updates of those previously estimated. These estimates are useful for building new indexes, updating existing selection indexes, and for predicting correlated responses due to inclusion of novel traits in the breeding programs.

Soil organic carbon stocks assessment in Mediterranean natural areas: a comparison of entire soil profiles and soil control sections.

Soil organic carbon (SOC) is an important part of the global carbon (C) cycle. In addition, SOC is a soil property subject to changes and highly variable in space and time. Over time, some researches have analyzed entire soil profile (ESP) by pedogenetic horizons and other researches have analyzed soil control sections (SCS) to different thickness. However, very few studies compare both methods (ESP versus SCS). This research sought to analyze the SOC stock (SOCS) variability using both methods (ESP and SCS) in The Despeñaperros Natural Park, a nature reserve that consists of a 76.8 km(2) forested area in southern Spain. Thirty-four sampling points were selected in the study zone. Each sampling point was analyzed in two different ways, as ESP (by horizons) and as SCS with different depth increments (0-25, 25-50, 50-75 and 75-100 cm). The major goal of this research was to study the SOCS variability at regional scale. The soils investigated in this study included Phaeozems, Cambisols, Regosols and Leptosols. Total SOCS in the Despeñaperros Natural Park was over 28.2% greater when SCS were used compared to ESP, ranging from 0.8144 Tg C (10,604.2 Mg km(-2)) to 0.6353 Tg C (8272.1 Mg km(-2)) respectively (1 Tg = 10(12) g). However, when the topsoil (surface horizon and superficial section control) was analyzed, this difference increased to 59.8% in SCS compared to ESP. The comparison between ESP and SCS showed the effect of mixing pedogenetic horizons when depth increments were analyzed. This indicates an overestimate of T-SOCS when sampling by SCS.

The incidence of hepatocellular carcinoma is reduced in patients with chronic hepatitis B on long-term nucleos(t)ide analogue therapy.

BACKGROUND: North American data are lacking on the effect of nucleos(t)ide analogues (NA) in preventing chronic hepatitis B (CHB)-related hepatocellular carcinoma (HCC). AIM: To determine the incidence of HCC in NA-treated patients and compare this risk with that predicted without treatment based on the REACH-B model. METHODS: In this retrospective study, the incidence of HCC was determined in CHB patients initiated on NA from 1999 to 2012. Pre-treatment data utilised in the REACH-B model were used to predict the annual HCC risk. The standardised incidence ratio (SIR) for HCC was calculated by comparing the observed to expected number of cases, and HCC risk factors determined by Cox proportional hazards regression. RESULTS: Five hundred and forty nine initiated NA (14% lamivudine, 5% adefovir, 1.5% telbivudine, 39% entecavir, 41% tenofovir). Over a median follow-up of 3.2 years (IQR 1.9-4.6), 11 (3.2%) were diagnosed with HCC. Among 322 with data to calculate the REACH-B model, the median age at treatment initiation was 46 years (IQR 38-55), 65% were male, 32% HBeAg positive and 20% had cirrhosis. The median pre-treatment ALT was 71 U/L (IQR 41-127) and HBV DNA was 6.48 log10 copies/mL (4.95-8.04). The observed annual HCC incidence (0.9%; 95% CI 0.5-1.7) was significantly lower than predicted without treatment by the REACH-B model (SIR 0.46; 95% CI 0.23-0.82); this risk was reduced after 4 years of therapy (SIR 0.49; 95% CI 0.2-1.00). CONCLUSIONS: In this Canadian study of nucleos(t)ide analogues-treated patients with chronic hepatitis B, the incidence of HCC was lower than expected, suggesting that NA reduce the risk of chronic hepatitis B-related HCC.

Frequency distribution of XbaIG > T and HaeIIIT > C GLUT1 polymorphisms among different Brazilian ethnic groups.

GLUT is the major glucose transporter in mammalian cells. Single nucleotide polymorphisms (SNP) at GLUT1 promoter and regulatory regions have been associated to the risk of developing nephropathy in different type 1 and type 2 diabetic populations. It has been demonstrated that differences in allelic and genotypic frequencies of GLUT1 gene (SLC2A1) polymorphisms occur among different populations. Therefore, ethnic differences in distribution of GLUT1 gene polymorphisms may be an important factor in determining gene-disease association. In this study, we investigated the XbaIG > T and HaeIIIT > C polymorphisms in six different Brazilian populations: 102 individuals from Salvador population (Northern Brazil), 56 European descendants from Joinville (South Brazil), 85 Indians from Tiryió tribe (North Brazil) and 127 samples from Southern Brazil: 44 from European descendants, 42 from African descendants and 41 from Japanese descendants. Genotype frequencies from both sites did not differ significantly from those expected under the Hardy-Weinberg equilibrium. We verified that the allele frequencies of both polymorphisms were heterogeneous in these six Brazilian ethnic groups.

Fas 670 promoter polymorphism is associated to susceptibility, clinical presentation, and survival in adult T cell leukemia.

Fas (TNFRSF6/Apo-1/CD95) is a type I transmembrane receptor, which mediates apoptosis. Fas gene mutations, aberrant transcripts, and abundant expression of Fas have been reported in adult T cell leukemia (ATL). To further elucidate the role of Fas in ATL pathogenesis, we investigated whether the -670 FAS promoter A/G polymorphism (STAT1-binding site) might contribute to susceptibility and clinical outcome in ATL. Thirty-one patients with ATL, 33 healthy, human T lymphotropic virus type 1-infected individuals, and 70 healthy, uninfected controls were genotyped for the FAS -670 polymorphism by PCR-restriction fragment-length polymorphism. The AA genotype was significantly over-represented in ATL patients in comparison with healthy controls (P=0.006), as well as asymptomatics (P=0.037), corresponding to an odds ratio (OR) of 3.79 [95% confidence intervals (CI; 1.28-11.41)] and 4.58 [95% CI (1.13-20.03)], respectively. The AA group also comprised significantly more aggressive (acute and lymphoma) clinical subtypes [P=0.012; OR=8.40; 95% CI (1.60-44.12)]. In addition, we observed a statistically significant association between GG genotype and survival (log rank test, P=0.032). Finally, IFN-gamma-induced but not basal FAS mRNA levels were increased significantly (P=0.049) in PBMCs from AA versus GG individuals, demonstrating the IFN-dependent functionality of the -670 polymorphism. In conclusion, our results demonstrate that a functional Fas promoter polymorphism is significantly associated to susceptibility, clinical manifestation, and survival in ATL.

Ethnic differences in the distribution of interleukin-6 polymorphisms among three Brazilian ethnic groups.

Polymorphisms in the interleukin-6 promoter region have been associated with diseases. In this study we investigated the -634G/C and -174G/C IL-6 promoter polymorphisms in three Brazilian ethnic groups. We verified that the allele frequencies of the two polymorphisms and haplotype frequencies varied significantly between the populations.

HTLV-1 modifies the clinical and immunological response to schistosomiasis.

The immunological response in HTLV-1 infected individuals is characterized by a prominent Type-1 cytokine response with high production of IFN-gamma and TNF-alpha. In contrast, helminthic infections and in particular chronic schistosomiasis are associated with a predominant production of IL-4, IL-5, IL-10 and IL-13. Liver fibrosis is the main pathological finding in schistosomiasis that occurs after many years of infection. This pathology is T cell dependent but the immune response mechanisms are not completely understood. The North-east region of Brazil is endemic for both HTLV-1 and schistosomiasis. In the present study the immune response, clinical severity, and therapeutic response to praziquantel of patients with schistosomiasis coinfected with HTLV-1 were compared with patients infected only with S. mansoni. Patients with HTLV-1 and S. mansoni had lower levels of IL-5 (P < 0.05) and higher levels of IFN-gamma (P < 0.05) in cultures stimulated with S. mansoni antigen and decreased S. mansoni antigen specific IgE levels when compared with patients with schistosomiasis without HTLV-1 coinfection. Liver fibrosis was mild in all HTLV-1 coinfected patients and efficacy of praziquantel was lower in patients dually infected than in patients infected only with S. mansoni.

The low evolutionary rate of human T-cell lymphotropic virus type-1 confirmed by analysis of vertical transmission chains.

The evolutionary rate of the human T-cell lymphotropic virus type-1 (HTLV-1) is considered to be very low, in strong contrast to the related human retrovirus HIV. However, current estimates of the HTLV-1 rate rely on the anthropological calibration of phylogenies using assumed dates of human migration events. To obtain an independent rate estimate, we analyzed two variable regions of the HTLV-1 genome (LTR and env) from eight infected families. Remarkable genetic stability was observed, as only two mutations in LTR (756 bp) and three mutations in env (522 bp) occurred within the 16 vertical transmission chains, including one ambiguous position in each region. The evolutionary rate in HTLV-1 was then calculated using a maximum-likelihood approach that used the highest and lowest possible times of HTLV-1 shared ancestry, given the known transmission histories. The rates for the LTR and env regions were 9.58 x 10(-8)-1.25 x 10(-5) and 7.84 x 10(-7) -2.33 x 10(-5)nucleotide substitutions per site per year, respectively. A more precise estimate was obtained for the combined LTR-env data set, which was 7.06 x 10(-7)-1.38 x 10(-5)substitutions per site per year. We also note an interesting correlation between the occurrence of mutations in HTLV-1 and the age of the individual infected.

Influence of human T-cell lymphocytotropic virus type 1 infection on serologic and skin tests for strongyloidiasis.

The aim of this study was to determine whether human T-cell lymphocytotropic virus type 1 (HTLV-1) infection may affect the levels of parasite-specific immunoglobulin (Ig) G and IgE and the positivity of the skin test for strongyloidiasis. Participants included 67 patients with strongyloidiasis (40 without HTLV-1 infection and 27 coinfected with HTLV-1). We determined IgG and IgE levels by enzyme-linked immunosorbent assay, and the immediate hypersensitivity skin test was performed with the metabolic Strongyloides stercoralis antigen. Specific IgE levels and the size of skin reactions in patients without HTLV-1 were higher (P < 0.01) than those observed in patients coinfected with HTLV-1. Additionally, 89% of patients without HTLV-1 had specific IgE and 92.5% had positive skin tests; however, these values were significantly reduced (P < 0.01) in patients coinfected with HTLV-1 (44% and 59%, respectively). These data show that HTLV-1 infection decreases the sensitivity of detection of S. stercoralis-specific IgE, the size of the immediate hypersensitivity reaction, and the sensitivity of these tests in the diagnosis of strongyloidiasis.

HTLV-1 decreases Th2 type of immune response in patients with strongyloidiasis.

Eosinophils, immunoglobulin (Ig)E and cytokines have important roles in defence mechanisms against helminths. In this study, the influence of HTLV-1 infection, characterized by a Th1 type of immune response, was evaluated on the cytokine pattern and parasitic specific IgE response in patients with strongyloidiasis. Patients were divided into four groups: strongyloidiasis without HTLV-1 infection, strongyloidiasis with HTLV-1, HTLV-1 without strongyloidiasis and controls without either helminth infection or HTLV-1. The cytokine profile was determined in supernatants of mononuclear cells stimulated with Strongyloides stercoralis crude antigen and the parasite specific IgE was measured by ELISA. Patients coinfected with HTLV-1 had higher levels of interferon (IFN)-gamma and interleukin (IL)-10 (P < 0.05) and lower levels of IL-5 and IgE (P < 0.05) than patients with strongyloidiasis without HTLV-1. There was an inverse relationship between IFN-gamma and IL-5 (P = 0.01; rs = - 0.37) and between IFN-gamma and parasite specific IgE (P = 0.01; rs = - 0.39), and a direct relationship between IFN-gamma and IL-10 (P = 0.04; rs = 0.35). These data show that coinfection with HTLV-1 decreases IL-5 and IgE responses in patients with strongyloidiasis consistent with a relative switch from Th2 to Th1 response. Immunological responses such as these are important in the control of this helminthic infection.

Human T-cell lymphotropic virus type 1 infection among pregnant women in northeastern Brazil.

An evaluation of human T-cell lymphotropic virus type 1 (HTLV-1) infection among 6754 pregnant women in Salvador, Bahia, Brazil using enzyme-linked immunosorbent assay, Western blot analysis, and polymerase chain reaction assay found a rate of infection of 0.84% (57 of 6754 women). Epidemiologic and obstetric data on the HTLV-1-positive pregnant women were analyzed and compared with data on a control group of HTLV-1-negative pregnant women. The mean age of the HTLV-1-positive women was 26.2 years. All were seronegative for HIV and syphilis, and only 2 reported a past history of sexually transmitted infection and more than 10 sexual partners. Of the HTLV-1-positive women, 88.5% were breast-fed, 4% were bottle fed, and 7.5% did not know. Six women had received blood transfusions, and only 1 reported intravenous drug use. Fifty-two HTLV-1-positive women could be followed: 45 had full-term deliveries, 5 had premature deliveries, and 2 had abortions. Our results indicate that (1) the frequency of HTLV-1 infection among pregnant women is relatively high in Salvador, Bahia, Brazil; (2) maternal infection was probably acquired more frequently through breast-feeding, but the sexual route was certainly the second most important means of transmission; (3) HTLV-1-positive women had a history of eczema-like infections in childhood more frequently than the control group; (4) HTLV-1 infection did not interfere in the course of pregnancy; and (5) no associated congenital infections were observed in the HTLV-1-positive women.

Herramientas para la gestión clínica / Tools for clinical management

No disponible

Solid state fermentation: acid protease production in controlled CO2 and O2 environments.

The effect of the partial pressure of O(2) and CO(2) on the acid protease production in solid state fermentation by Aspergillus niger on wheat bran was studied. A fermentation system was used, which allowed on-line reactor measurements and continuous data acquisition of pH, temperature, gas flow, pressure drop and CO(2) production. Six paired combinations of CO(2) and O(2) concentrations were studied. The results showed a direct relationship between pressure drop, production of CO(2) and temperature increase. The pH evolution patterns were similar in all cases but different if the measurements were made on-line or on a liquid homogenate of the fermented substrate. Acid protease production was increased when the gas had 4% CO(2), (vol/vol), and it reached its highest level, a 43% increase over air, with a mixture of 4% CO(2) and 21% O(2). The protease production was strongly related to the mold metabolic activity as represented by the total CO(2) evolved.