Antimicrobial Activities of α-Helix and ß-Sheet Peptides against the Major Bovine Respiratory Disease Agent, Mannheimia haemolytica.

Bovine respiratory disease (BRD) is the leading cause of morbidity and mortality in cattle raised in North America. At the feedlot, cattle are subject to metaphylactic treatment with macrolides to prevent BRD, a practice that may promote antimicrobial resistance and has resulted in an urgent need for novel strategies. Mannheimia haemolytica is one of the major bacterial agents of BRD. The inhibitory effects of two amphipathic, α-helical (PRW4, WRL3) and one ß-sheet (WK2) antimicrobial peptides were evaluated against multidrug-resistant (MDR) M. haemolytica isolated from Alberta feedlots. WK2 was not cytotoxic against bovine turbinate (BT) cells by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. All three peptides inhibited M. haemolytica, with WK2 being the most efficacious against multiple isolates. At 8-16 µg/mL, WK2 was bactericidal against Mh 330 in broth, and at 32 µg/mL in the presence of BT cells, it reduced the population by 3 logs CFU/mL without causing cytotoxic effects. The membrane integrity of Mh 330 was examined using NPN (1-N-phenylnaphthylamine) and ONPG (o-Nitrophenyl ß-D-galactopyranoside), with both the inner and outer membranes being compromised. Thus, WK2 may be a viable alternative to the use of macrolides as part of BRD prevention and treatment strategies.

Exposure to Secondhand Smoke Extract Increases Cisplatin Resistance in Head and Neck Cancer Cells.

Chemotherapy and radiotherapy resistance are major obstacles in the long-term efficacy of head and neck squamous cell carcinoma (HNSCC) treatment. Secondhand smoke (SHS) exposure is common and has been proposed as an independent predictor of HNSCC recurrence and disease-free survival. However, the underlying mechanisms responsible for these negative patient outcomes are unknown. To assess the effects of SHS exposure on cisplatin efficacy in cancer cells, three distinct HNSCC cell lines were exposed to sidestream (SS) smoke, the main component of SHS, at concentrations mimicking the nicotine level seen in passive smokers' saliva and treated with cisplatin (0.01-100 µM) for 48 h. Compared to cisplatin treatment alone, cancer cells exposed to both cisplatin and SS smoke extract showed significantly lower cisplatin-induced cell death and higher cell viability, IC50, and indefinite survival capacity. However, SS smoke extract exposure alone did not change cancer cell viability, cell death, or cell proliferation compared to unexposed control cancer cells. Mechanistically, exposure to SS smoke extract significantly reduced the expression of cisplatin influx transporter CTR1, and increased the expression of multidrug-resistant proteins ABCG2 and ATP7A. Our study is the first to document that exposure to SHS can increase cisplatin resistance by altering the expression of several proteins involved in multidrug resistance, thus increasing the cells' capability to evade cisplatin-induced cell death. These findings emphasize the urgent need for clinicians to consider the potential role of SHS on treatment outcomes and to advise cancer patients and caregivers on the potential benefits of avoiding SHS exposure.

The Isolation and Characterization of Bacteriophages Infecting Avian Pathogenic Escherichia coli O1, O2 and O78 Strains.

Avian pathogenic Escherichia coli (APEC), such as O1, O2 and O78, are important serogroups relating to chicken health, being responsible for colibacillosis. In this study, we isolated and characterized bacteriophages (phages) from hen feces and human sewage in Alberta with the potential for controlling colibacillosis in laying hens. The lytic profile, host range, pH tolerance and morphology of seven APEC-infecting phages (ASO1A, ASO1B, ASO2A, ASO78A, ASO2B, AVIO78A and ASO78B) were assessed using a microplate phage virulence assay and transmission electron microscopy (TEM). The potential safety of phages at the genome level was predicted using AMRFinderPlus and the Virulence Factor Database. Finally, phage genera and genetic relatedness with other known phages from the NCBI GenBank database were inferred using the virus intergenomic distance calculator and single gene-based phylogenetic trees. The seven APEC-infecting phages preferentially lysed APEC strains in this study, with ECL21443 (O2) being the most susceptible to phages (n = 5). ASO78A had the broadest host range, lysing all tested strains (n = 5) except ECL20885 (O1). Phages were viable at a pH of 2.5 or 3.5-9.0 after 4 h of incubation. Based on TEM, phages were classed as myovirus, siphovirus and podovirus. No genes associated with virulence, antimicrobial resistance or lysogeny were detected in phage genomes. Comparative genomic analysis placed six of the seven phages in five genera: Felixounavirus (ASO1A and ASO1B), Phapecoctavirus (ASO2A), Tequatrovirus (ASO78A), Kayfunavirus (ASO2B) and Sashavirus (AVIO78A). Based on the nucleotide intergenomic similarity (<70%), phage ASO78B was not assigned a genus in the siphovirus and could represent a new genus in class Caudoviricetes. The tail fiber protein phylogeny revealed variations within APEC-infecting phages and closely related phages. Diverse APEC-infecting phages harbored in the environment demonstrate the potential to control colibacillosis in poultry.

Auction market placement and a rest stop during transportation affect the respiratory bacterial microbiota of beef cattle.

Background: Bovine respiratory disease (BRD) is a significant health problem in beef cattle production, resulting in considerable economic losses due to mortalities, cost of treatment, and reduced feed efficiency. The onset of BRD is multifactorial, with numerous stressors being implicated, including transportation from farms to feedlots. In relation to animal welfare, regulations or practices may require mandatory rest times during transportation. Despite this, there is limited information on how transportation and rest stops affect the respiratory microbiota. Results: This study evaluated the effect of cattle source (ranch-direct or auction market-derived) and rest stop duration (0 or 8 h of rest) on the upper respiratory tract microbiota and its relationship to stress response indicators (blood cortisol and haptoglobin) of recently weaned cattle transported for 36 h. The community structure of bacteria was altered by feedlot placement. When cattle were off-loaded for a rest, several key bacterial genera associated with BRD (Mannheimia, Histophilus, Pasteurella) were increased for most sampling times after feedlot placement for the ranch-direct cattle group, compared to animals given no rest stop. Similarly, more sampling time points had elevated levels of BRD-associated genera when auction market cattle were compared to ranch-direct. When evaluated across time and treatments several genera including Mannheimia, Moraxella, Streptococcus and Corynebacterium were positively correlated with blood cortisol concentrations. Conclusion: This is the first study to assess the effect of rest during transportation and cattle source on the respiratory microbiota in weaned beef calves. The results suggest that rest stops and auction market placement may be risk factors for BRD, based solely on increased abundance of BRD-associated genera in the upper respiratory tract. However, it was not possible to link these microbiota to disease outcome, due to low incidence of BRD in the study populations. Larger scale studies are needed to further define how transportation variables impact cattle health.

Corrigendum: IgG2 rules: N-acetyl-ß-D-glucosamine-specific IgG2 and Th17/Th1 cooperation may promote the pathogenesis of acute rheumatic heart disease and be a biomarker of the autoimmune sequelae of Streptococcus pyogenes.

[This corrects the article DOI: 10.3389/fcvm.2022.919700.].

[Active surveillance for thyroid micro-malignant nodules].

Objective: To evaluate the effect of ultrasound diagnosis of thyroid micro-malignant nodules and accumulate practical experience for the management of active surveillance for them, so as to avoid overtreatment. Methods: A total of 949 patients who were diagnosed with thyroid malignant nodules using ultrasonography, with the nodules being less than 1 cm in size and without regional lymph node metastasis or distant metastasis, were included. They were treated by the same surgeon of the Department of Head and Neck Surgery, Cancer Hospital, Chinese Academy of Medical Sciences from February 2014 to December 2020. 112 patients chose immediate surgery. The rest patients were asked to accept ultrasound examination every 6 months to 1 year. Follow-up endpoints: tumor size growth of 3 mm, tumor volume increase greater than 50%, lymph node metastasis or distant metastasis. Results: The median follow-up time was 19 months. 713 patients underwent surveillance for more than 6 months. Of the 713 patients, 570 (79.9%) were women, with mean age at 43.5 years old. Tumor progression was observed in 47 (6.6%) patients with a cumulative incidence of 2.7% (1 year), 7.2% (2 years) and 9.5% (3 years). In multivariate analysis, patient age [HR=0.508, 95%CI: 0.275-0.939, P=0.031], lesion number [HR=2.945, 95%CI: 1.593-5.444, P=0.001] and tumor size [HR=2.245, 95%CI: 1.202-4.192, P=0.011] at the beginning of observation were independent risk factors for tumor progression in patients with minimal thyroid malignant nodules during follow-up. During a median (range) active surveillance of 19 (6-80) months, 74 patients chose surgery during the surveillance. Among the 186 patients who underwent surgery, only 3 patients were diagnosed with fibrotic nodules in pathology, while the rest were papillary thyroid carcinoma. The ultrasound accuracy reached 98.4%(183/186). Conclusions: Ultrasonography is an effective method of diagnosing malignant thyroid nodules. Thyroid micro-malignant nodules progress slowly. As a result, it is safe to observe them instead of taking immediate surgery. Patient age, lesion number and tumor size at the beginning of observation are independent risk factors for the tumor progression of malignant nodules.

Biological and genomic characteristics of two bacteriophages isolated from sewage, using one multidrug-resistant and one non-multidrug-resistant strain of Klebsiella pneumoniae.

Bovine mastitis caused by multi-drug resistant (MDR) Klebsiella pneumoniae is difficult to treat with antibiotics, whereas bacteriophages may be a viable alternative. Our objective was to use 2 K. pneumoniae strains, 1 MDR and the other non-MDR, to isolate phages from sewage samples and compare their biological and genomic characteristics. Additionally, phage infected mouse mammary gland was also analyzed by H&E staining and ELISA kits to compare morphology and inflammatory factors, respectively. Based on assessments with double agar plates and transmission electron microscopy, phage CM_Kpn_HB132952 had clear plaques surrounded by translucent halos on the bacterial lawn of K. pneumoniae KPHB132952 and belonged to Siphoviridae, whereas phage CM_Kpn_HB143742 formed a clear plaque on the bacterial lawn of K. pneumoniae KPHB143742 and belonged to Podoviridae. In 1-step growth curves, CM_Kpn_HB132952 and CM_Kpn_HB143742 had burst sizes of 0.34 and 0.73 log10 PFU/mL, respectively. The former had a latent period of 50 min and an optimal multiplicity of infection (MOI) of 0.01, whereas for the latter, the latent period was 30 min (MOI = 1). Phage CM_Kpn_HB132952 had better thermal and acid-base stability than phage CM_Kpn_HB143742. Additionally, both phages had the same host range rate but different host ranges. Based on Illumina NovaSeq, phages CM_Kpn_HB132952 and CM_Kpn_HB143742 had 140 and 145 predicted genes, respectively. Genomic sequencing and phylogenetic tree analysis indicated that both phages were novel phages belonging to the Klebsiella family. Additionally, the histopathological structure and inflammatory factors TNF-α and IL-1ß were not significantly different among phage groups and the control group. In conclusion, using 1 MDR and 1 non-MDR strain of K. pneumoniae, we successfully isolated two phages from the same sewage sample, and demonstrated that they had distinct biological and genomic characteristics.

Ameliorating effect of Trigonella foenum-graecum L. (fenugreek) extract tablet on exhaustive exercise-induced fatigue in rats by suppressing mitophagy in skeletal muscle.

OBJECTIVE: Trigonella foenum-graecum L. (fenugreek) is widely used as a leafy vegetable and spice in China and North Africa. Recent studies have reported that fenugreek can reduce fatigue; however, its antifatigue mechanism remains unclear. Therefore, this study aimed to investigate the potential antifatigue effects of fenugreek extract (FE) on mitophagy and the underlying mechanisms. MATERIALS AND METHODS: We evaluated the potential effects of FE tablet on an exhaustive exercise-induced fatigue (EEF) rat model. Oxidative stress indicators and fatigue biomarkers in the serum and skeletal muscle were detected. Mitophagy and mitochondrial morphology were observed using transmission electron microscopy. The expression levels of mitochondrial autophagy-related proteins were detected using western blot and immunofluorescence. RESULTS: Compared with the model group, FE enhanced the activities of the antioxidant enzymes superoxide dismutase and glutathione peroxidase as well as total antioxidant capacity; however, it decreased the level of malondialdehyde in the serum and skeletal muscle after a 7-day treatment. Moreover, certain indicators of mitochondrial function, such as reactive oxygen species levels, ATP levels, cellular and mitochondrial Ca2+ levels, and ATPase activity, were significantly improved in the FE group compared with the model group. Finally, we found that mitophagy was induced by exhaustive exercise and inhibited by FE. Regarding mitochondrial autophagy-related proteins, the expression levels of LC3B, FUNDC1, PGAM5, PARKIN, and PINK1 in the skeletal muscle tissue were increased in the EEF group compared with the control group. After administration of FE and a positive control drug, a significant reversal in the expression of the above-mentioned proteins was noted. CONCLUSIONS: Our findings demonstrate that FE exerted antifatigue effects in the EEF rat model by regulating the mitophagy-related FUNDC1/LC3B signaling pathway rather than the PINK1/PARKIN signaling pathway.

Novel Experimental In-Office Bleaching Gels Containing Co-Doped Titanium Dioxide Nanoparticles.

The present study reports on the development and testing of novel bleaching agents containing co-doped metaloxide nanoparticles (NP; 0%, 5%, 10% v/w) and hydrogen peroxide (HP, 0%, 6%, 15%, and 35%). Bovine blocks (n = 200, A = 36 mm2) were obtained and randomly distributed into experimental groups (n = 10/group). NPs were incorporated into gels before bleaching (3 sessions, 7 days apart, 30 min/session, irradiated with violet light-LT). Color changes (ΔE00, ΔWID), mineral content (CO32−, PO43−), and topography were assessed (spectrophotometer, ATR-FTIR, and AFM) before and after bleaching procedures (14 days). Metabolic status and three-dimensional components of non-disrupted Streptococcus mutans biofilms were investigated using a multimode reader and confocal microscopy. The results indicate that ΔE00 and ΔWID significantly increased with NPs' concentrations and LT. The enamel's mineral ratio was adversely impacted by HP, but alterations were less pronounced when using NP-containing gels. The enamel's topography was not damaged by the bleaching protocols tested. The bioluminescence results show that bleaching protocols do not render latent antibacterial properties to enamel, and the confocal microscopy results demonstrate that the 3-dimensional distribution of the components was affected by the protocols. The proposed nanotechnology improved the bleaching efficacy of experimental materials independent of hydrogen peroxide or irradiation and did not adversely impact the enamel's surface properties or its chemical content.

The molecular basis of spinocerebellar ataxia type 48 caused by a de novo mutation in the ubiquitin ligase CHIP.

The spinocerebellar ataxias (SCAs) are a class of incurable diseases characterized by degeneration of the cerebellum that results in movement disorder. Recently, a new heritable form of SCA, spinocerebellar ataxia type 48 (SCA48), was attributed to dominant mutations in STIP1 homology and U box-containing 1 (STUB1); however, little is known about how these mutations cause SCA48. STUB1 encodes for the protein C terminus of Hsc70 interacting protein (CHIP), an E3 ubiquitin ligase. CHIP is known to regulate proteostasis by recruiting chaperones via a N-terminal tetratricopeptide repeat domain and recruiting E2 ubiquitin-conjugating enzymes via a C-terminal U-box domain. These interactions allow CHIP to mediate the ubiquitination of chaperone-bound, misfolded proteins to promote their degradation via the proteasome. Here we have identified a novel, de novo mutation in STUB1 in a patient with SCA48 encoding for an A52G point mutation in the tetratricopeptide repeat domain of CHIP. Utilizing an array of biophysical, biochemical, and cellular assays, we demonstrate that the CHIPA52G point mutant retains E3-ligase activity but has decreased affinity for chaperones. We further show that this mutant decreases cellular fitness in response to certain cellular stressors and induces neurodegeneration in a transgenic Caenorhabditis elegans model of SCA48. Together, our data identify the A52G mutant as a cause of SCA48 and provide molecular insight into how mutations in STUB1 cause SCA48.

[Risk factors of residual tumor in single small hepatocellular carcinoma after thermal ablation treatment].

Objective: To evaluate the risk factors of residual tumor after thermal ablation in patients with small hepatocellular carcinoma. Methods: This was a retrospective study recruiting 107 patients diagnosed as single hepatocellular carcinoma with maximum diameter ≤3 cm from December 2009 to August 2015 in National Cancer Center. The cohort enrolled 81 males and 26 females, including 83 patients younger than 70 years old. All patients were treated with radiofrequency ablation or microwave ablation, and evaluated by CT or MRI after 4-6 weeks compared with baseline data. Potentially related factors were analyzed such as patients' characteristics, tumor location and adjacent, ablation pattern, hepatitis B/C infection. A multivariate logistic regression analysis was conducted for the independence of risk factors. Results: Six patients (5.6%) with residual tumor was detected in the whole population of 101 cases. Univariate analysis suggested that tumor adjacent to vascular structure, poor differentiation, AFP≥200 µg/L were the risk factors of residue disease (all P<0.05). Multivariate logistic regression suggested that pathological type of poorly differentiated tumor was the only independent risk factor (HR=2.26,95%CI 0.25-20.50, P=0.030). Conclusions: Poorly differentiated pathology is an independent predictive factor for residual disease in small hepatocellular carcinoma after thermal ablation. Such patients should be routinely followed up after operation.

Vaginal-perianal or vaginal-perineal compared with vaginal-rectal culture-based screening for Group B Streptococci (GBS) colonization during the third trimester of pregnancy: a systematic review and meta-analysis.

BACKGROUND: Screening for maternal anogenital Group B streptococci (GBS) colonization in pregnancy with initiation of intravenous intrapartum antibiotic prophylaxis as indicated has led to a significant reduction in the incidence of neonatal GBS infection. This study aims to evaluate the agreement between vaginal-perianal or vaginal-perineal culture and the more typically used vaginal-rectal culture for screening for maternal anogenital GBS colonization in the third trimester of pregnancy. METHODS: Eligible English-language studies published until January 2020 were retrieved from Scopus, Web of Science, PubMed, Embase, and ClinicalTrials.gov databases. Studies were compiled that assessed for GBS colonization utilizing vaginal-perianal or vaginal-perineal culture and vaginal-rectal culture during the third trimester of pregnancy. Nonoriginal research articles and studies that did not assess pregnant patients, did not use culture-based screening, or did not compare vaginal-perianal or vaginal-perineal culture with vaginal-rectal culture were excluded. The search identified 559 articles with three prospective cohort studies that met inclusion criteria, including 643 participants. Quality was assessed using the Newcastle-Ottawa Scale, and risk of bias was assessed using the Risk of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool. Patient characteristics and associated pain with specimen collection were abstracted. Meta-analyses of both the raw agreement and the Cohen's kappa statistic were performed. RESULTS: Within the three included studies, the range of GBS detection was 17.6-34.0%, consistent with the anticipated prevalence of GBS colonization reported in earlier publications. For both raw agreement and Cohen's kappa coefficient, the test for heterogeneity was not significant, indicating low heterogeneity among studies. The pooled estimate of the raw agreement was 0.97 (95%CI 0.95-0.98) and of the Cohen's kappa coefficient was 0.91 (95% CI: 0.87-0.95), indicating (according to the Landis and Koch criteria) an "almost perfect" agreement between the compared clinical tests. In the two studies that assessed procedure-related patient discomfort, vaginal-rectal swabbing caused more discomfort. CONCLUSION: Use of vaginal-perineal culture for assessment of maternal GBS colonization is comparable to the more typically utilized vaginal-rectal culture and is associated with less discomfort.

Genomic Profiling of Non-O157 Shiga Toxigenic Escherichia coli-Infecting Bacteriophages from South Africa.

Background: Non-O157 Shiga toxigenic Escherichia coli (STEC) are one of the most important food and waterborne pathogens worldwide. Although bacteriophages (phages) have been used for the biocontrol of these pathogens, a comprehensive understanding of the genetic characteristics and lifestyle of potentially effective candidate phages is lacking. Materials and Methods: In this study, 10 non-O157-infecting phages previously isolated from feedlot cattle and dairy farms in the North-West province of South Africa were sequenced, and their genomes were analyzed. Results: Comparative genomics and proteomics revealed that the phages were closely related to other E. coli-infecting Tunaviruses, Seuratviruses, Carltongylesviruses, Tequatroviruses, and Mosigviruses from the National Center for Biotechnology Information GenBank database. Phages lacked integrases associated with a lysogenic cycle and genes associated with antibiotic resistance and Shiga toxins. Conclusions: Comparative genomic analysis identified a diversity of unique non-O157-infecting phages, which could be used to mitigate the abundance of various non-O157 STEC serogroups without safety concerns.

Intra-couple discordance in preconception syphilis screening for both spouses: a national and population-based survey in China, 2013-2018.

OBJECTIVE: The antenatal screening strategy remains inadequate for eliminating congenital syphilis. To further eliminate maternal fetal transmission, preconception syphilis screening is considered an option. In this study, we investigated syphilis seropositivity and intra-couple discordance among married couples planning a pregnancy in China to provide essential baseline evidence for preconception syphilis screening. DESIGN: Population-based survey. SETTING: National preconception registered data. POPULATION: Married Chinese couples planning conception within 6 months between 2013 and 2018. METHODS: Syphilis was screened using rapid plasma reagin (RPR); infection self-reporting and sociodemographic characteristics were collected through questionnaires and medical records, respectively. r 3.2.2 and arcgis 10.2 were used for statistical analyses and geographic mapping. MAIN OUTCOME MEASURES: RPR seropositivity. RESULTS: Among 31 955 041 couples, 29 737 172 (93.06%) had complete RPR results for both spouses; of those, 0.62% (186 100) were seropositive, with dramatic intra-couple discordance, with 0.33% positivity in wives, 0.24% positivity in husbands and 0.05% positivity in both spouses. Across time, both seropositivity and intra-couple discordance remained stable. Seropositivity in different regions varied significantly, with provincial rates ranging geographically from Tibet (0.8%) to Hebei (0.2%) (P < 0.05). Economic level was an independent factor for this regional variation, with seropositivity increasing as gross domestic product income decreased (P < 0.05). CONCLUSIONS: Intra-couple discordance in seropositivity for syphilis is notable among couples, with a considerable rate of pre-existing syphilis before pregnancy. Thus, screening both spouses during integrated preconception health care is recommended for further eliminating maternal-fetal transmission. TWEETABLE ABSTRACT: Intra-couple discordance in seropositivity for syphilis is notable among couples, with a considerable rate of pre-existing syphilis before pregnancy. Screening both spouses during integrated preconception health care is recommended to further eliminate maternal-fetal transmission.

The association between the vaginal microenvironment and fecundability: a register-based cohort study among Chinese women.

OBJECTIVE: To evaluate the association between the vaginal microenvironment and fecundability among women. DESIGN: Register-based nationwide cohort study. SETTING: Chinese National Free Pre-conception Check-up Project from 2015 to 2018. POPULATION: Our study included a total of 3 388 554 eligible women who were attempting to become pregnant. METHOD: We assessed the vaginal microenvironment at baseline by considering four indices: vaginal pH, clue cell examination, whiff test and vaginal cleanliness grading. If any of these indicators was abnormal, the vaginal microenvironment was defined as poor. Propensity score matching was used to control for potential confounders and reduce bias. Logistic models were used to estimate the fecundability odds ratios (FORs) after adjustment for covariates. MAIN OUTCOME MEASURES: Achievement of a pregnancy within 1 year. RESULTS: Of the total study population, 379 718 women (11.2%) had a poor vaginal microenvironment and their pregnancy rate after 1 year was significantly lower than the group with a normal microenvironment (71.8% versus 76.1%, P < 0.001). After adjusting for potential confounders, the women with a poor vaginal microenvironment were associated with a 9% reduction in fecundability compared with the normal microenvironment group (FOR 0.91, 95% CI 0.90-0.92). The adverse effects of a poor vaginal microenvironment were stronger among multipara (FOR 0.89, 95% CI 0.87-0.90) or women with irregular menstruation (FOR 0.86, 95% CI 0.84-0.89). CONCLUSION: There was a negative association between a poor vaginal microenvironment and the fecundability of women. These findings highlight the significance of assessing the vaginal microenvironment during pre-pregnancy health examinations. TWEETABLE ABSTRACT: Women with a poor vaginal microenvironment were associated with a reduction in fecundability.