RESUMO
We aimed to evaluate the impact of selective dry cow therapy (SDCT) (protocol 1: antimicrobial combined with internal teat sealant (ITS); vs. protocol 2: ITS alone) on bacterial diversity and the abundance of quarter milk. Eighty high production cows (parity ≤ 3 and an average milk yield of 36.5 kg/cow/day) from the largest Brazilian dairy herd available were randomly selected; milk quarter samples were collected for microbiological culture (MC) on the day of drying-off (n = 313) and on day 7 post-calving (n = 313). Based on the results of the MC before and after calving, 240 quarters out of 313 were considered healthy, 38 were cured, 29 showed new infections and 6 had persistent infections. Mammary quarters were randomly selected based on intramammary information status and SDCT protocols for bacterial diversity analyses. The bacterial diversity was similar when comparing both healthy and cured quarters submitted to both drying-off protocols. Despite healthy cows that were treated at dry-off using only teat sealant showing no alteration in the alpha and beta bacterial diversity, they did show a higher abundance of bacterial groups that may be beneficial to or commensals of the mammary gland, which implies that antibiotic therapy should be reserved for mammary quarters with a history of mastitis.
RESUMO
A 69-year-old Native American female with a past medical history of end-stage renal disease presented to our rural outpatient dialysis access center. One and a half years prior, the patient's arteriovenous fistula was banded due to venous steal syndrome and now demonstrated an abnormal bruit with decreased blood flow during dialysis. On arteriogram, she was found to have a 90% narrowing of her previously banded cephalic vein along with stenosis of the arterial anastomosis and subclavian vein. Balloon angioplasty was performed on the subclavian vein stenosis, and the banded cephalic vein was ruptured. However, the arterial anastomosis stenosis was left untreated due to the patient's previous venous steal syndrome.
RESUMO
A 42-year-old female with a past medical history of femoral facial syndrome (FFS) and years of gastroesophageal reflux disease presented to our clinic with symptoms of dysphagia and iron deficiency anemia. On upper endoscopy, esophageal stricture and adenocarcinoma were detected. Unfortunately, the patient developed coronavirus disease 2019 (COVID-19) multi-organ failure prior to cancer treatment and died with dignity after choosing comfort care measures. To the best of our knowledge, we report the first case of FFS in an adult patient. This case also uniquely highlights the rare gastrointestinal manifestations of FFS.
RESUMO
Bacteriophage exclusion ('BREX') phage restriction systems are found in a wide range of bacteria. Various BREX systems encode unique combinations of proteins that usually include a site-specific methyltransferase; none appear to contain a nuclease. Here we describe the identification and characterization of a Type I BREX system from Acinetobacter and the effect of deleting each BREX ORF on growth, methylation, and restriction. We identified a previously uncharacterized gene in the BREX operon that is dispensable for methylation but involved in restriction. Biochemical and crystallographic analyses of this factor, which we term BrxR ('BREX Regulator'), demonstrate that it forms a homodimer and specifically binds a DNA target site upstream of its transcription start site. Deletion of the BrxR gene causes cell toxicity, reduces restriction, and significantly increases the expression of BrxC. In contrast, the introduction of a premature stop codon into the BrxR gene, or a point mutation blocking its DNA binding ability, has little effect on restriction, implying that the BrxR coding sequence and BrxR protein play independent functional roles. We speculate that elements within the BrxR coding sequence are involved in cis regulation of anti-phage activity, while the BrxR protein itself plays an additional regulatory role, perhaps during horizontal transfer.
Assuntos
Acinetobacter/fisiologia , Fatores de Restrição Antivirais , Bacteriófagos , Acinetobacter/genética , Acinetobacter/virologia , Fatores de Restrição Antivirais/genética , Bacteriófagos/fisiologia , DNA/metabolismo , Metiltransferases/genética , ÓperonRESUMO
A 71-year-old Caucasian male with a past medical history of Charcot-Marie-Tooth disease type 2 presented to our rural hospital for left knee pain, swelling, and difficulty walking. The patient had prior bilateral total knee replacements with a subsequent left knee revision due to infection. Joint aspiration was culture-positive and 16S recombinant DNA (rDNA) sequence positive for Abiotrophia defectiva. The patient underwent a left total knee extraction with a temporary antibiotic spacer insertion. On discharge, the patient received an initial six weeks of ceftriaxone 2g IV. At the outpatient six-week follow-up, the patient was cleared of the Abiotrophia infection. However, later complications and a subsequent Enterobacter cloacae infection arose.
RESUMO
Analysis of the cow microbiome, as well as host genetic influences on the establishment and colonization of the rumen microbiota, is critical for development of strategies to manipulate ruminal function toward more efficient and environmentally friendly milk production. To this end, the development and validation of noninvasive methods to sample the rumen microbiota at a large scale are required. In this study, we further optimized the analysis of buccal swab samples as a proxy for direct bacterial samples of the rumen of dairy cows. To identify an optimal time for sampling, we collected buccal swab and rumen samples at six different time points relative to animal feeding. We then evaluated several biases in these samples using a machine learning classifier (random forest) to select taxa that discriminate between buccal swab and rumen samples. Differences in the inverse Simpson's diversity, Shannon's evenness, and Bray-Curtis dissimilarities between methods were significantly less apparent when sampling was performed prior to morning feeding (P < 0.05), suggesting that this time point was optimal for representative sampling. In addition, the random forest classifier was able to accurately identify nonrumen taxa, including 10 oral and putative feed-associated taxa. Two highly prevalent (>60%) taxa in buccal and rumen samples had significant variance in relative abundances between sampling methods but could be qualitatively assessed via regular buccal swab sampling. This work not only provides new insights into the oral community of ruminants but also further validates and refines buccal swabbing as a method to assess the rumen bacterial in large herds.IMPORTANCE The gastrointestinal tracts of ruminants harbor a diverse microbial community that coevolved symbiotically with the host, influencing its nutrition, health, and performance. While the influence of environmental factors on rumen microbes is well documented, the process by which host genetics influences the establishment and colonization of the rumen microbiota still needs to be elucidated. This knowledge gap is due largely to our inability to easily sample the rumen microbiota. There are three common methods for rumen sampling but all of them present at least one disadvantage, including animal welfare, sample quality, labor, and scalability. The development and validation of noninvasive methods, such as buccal swabbing, for large-scale rumen sampling is needed to support studies that require large sample sizes to generate reliable results. The validation of buccal swabbing will also support the development of molecular tools for the early diagnosis of metabolic disorders associated with microbial changes in large herds.