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Biochemical and Biophysical Research... Sep 2021The crystal structure of l-lactate oxidase in complex with l-lactate was solved at a 1.33 Å resolution. The electron density of the bound l-lactate was clearly shown...
The crystal structure of l-lactate oxidase in complex with l-lactate was solved at a 1.33 Å resolution. The electron density of the bound l-lactate was clearly shown and comparisons of the free form and substrate bound complexes demonstrated that l-lactate was bound to the FMN and an additional active site within the enzyme complex. l-lactate interacted with the related side chains, which play an important role in enzymatic catalysis and especially the coupled movement of H265 and D174, which may be essential to activity. These observations not only reveal the enzymatic mechanism for l-lactate binding but also demonstrate the dynamic motion of these enzyme structures in response to substrate binding and enzymatic reaction progression.
Topics: Aerococcus; Bacterial Proteins; Binding Sites; Catalytic Domain; Crystallography, X-Ray; Hydrogen-Ion Concentration; Lactic Acid; Mixed Function Oxygenases; Models, Molecular; Substrate Specificity
PubMed: 34214876
DOI: 10.1016/j.bbrc.2021.06.078 -
Ophthalmic Surgery, Lasers & Imaging... Jun 2021To report the incidence and clinical features of infectious endophthalmitis after intravitreal (IV) injection of anti-vascular endothelial growth factor inhibitors...
BACKGROUND AND OBJECTIVE
To report the incidence and clinical features of infectious endophthalmitis after intravitreal (IV) injection of anti-vascular endothelial growth factor inhibitors (VEGF) between 2018 and 2020 and to compare to prior rates.
PATIENTS AND METHODS
Retrospective analysis of patients with endophthalmitis after anti-VEGF IV injections treated at Bascom Palmer Eye Institute between January 1, 2018, and December 31, 2020.
RESULTS
Between 2018 and 2020, the rate of clinically diagnosed endophthalmitis was 0.014% (10/71,858) and of culture-positive was 0.008% (6/71,858). Clinically diagnosed endophthalmitis rates per injection were: aflibercept (0.022%); ranibizumab (0.019%); bevacizumab (0%); and brolucizumab (0%). Clinically diagnosed endophthalmitis rates were similar in the present study compared to those from 2005 to 2017 ( = .84). Fifteen eyes were diagnosed with endophthalmitis (10 in-house, five external referrals). Of culture-positive eyes, the organisms were coagulase-negative (8/11), species (2/11), and (1/11). A universal face-masking policy in 2020 did not lower infection rates ( = .73).
CONCLUSION
Endophthalmitis rates after IV anti-VEGF remain low and are similar to prior reports. .
Topics: Abiotrophia; Angiogenesis Inhibitors; Bevacizumab; Endophthalmitis; Eye Infections, Bacterial; Humans; Incidence; Intravitreal Injections; Ranibizumab; Retrospective Studies; Tertiary Care Centers; Vascular Endothelial Growth Factor A
PubMed: 34185586
DOI: 10.3928/23258160-20210528-04 -
BMJ Case Reports Jun 2021is a nutritional variant streptococcus, with affinity for endovascular structures that cannot be cultured on non-supplemented media, leading to a delay in diagnosis....
is a nutritional variant streptococcus, with affinity for endovascular structures that cannot be cultured on non-supplemented media, leading to a delay in diagnosis. This case describes a 36-year-old woman with a previously known bicuspid aortic valve that presented with asthenia, myalgias and anorexia with 2-month onset. On admission, we documented fever and a systolic murmur. Transthoracic echocardiography revealed an oscillating mass attached to the aortic valve. The patient was admitted with a possible diagnosis of infective endocarditis. Later, blood cultures were positive for Due to severe aortic regurgitation and congestive heart failure, she underwent surgical aortic valve replacement. After 6 weeks of antimicrobial therapy, the patient experienced full recovery. Despite of its rarity, endocarditis is associated with significant morbidity with mortality and physicians must have a high level of suspicion to ensure a prompt diagnosis and provide the appropriate treatment.
Topics: Abiotrophia; Adult; Endocarditis; Endocarditis, Bacterial; Female; Gram-Positive Bacterial Infections; Humans
PubMed: 34155014
DOI: 10.1136/bcr-2021-241964 -
Journal of Clinical Microbiology Jul 2021Aerococcus urinae is a urinary pathogen with well-described resistance to fluoroquinolones. This study aimed to validate the gradient diffusion (GD) method (Etest) on...
Aerococcus urinae is a urinary pathogen with well-described resistance to fluoroquinolones. This study aimed to validate the gradient diffusion (GD) method (Etest) on cation-adjusted Mueller-Hinton agar with 5% sheep blood for testing the susceptibilities of Aerococcus urinae to the antimicrobial agents ciprofloxacin and levofloxacin and to compare the Etest to the broth microdilution (BMD) method from CLSI document M45-A3. Agar dilution (AD), as recommended by EUCAST, was used as an alternative reference method to arbitrate discrepancies or address technical issues. Aerococcus urinae isolates from urinary specimens were prospectively collected between June 2016 and December 2017 from six hospitals in Quebec, Canada, and identifications were confirmed using Vitek MS with the IVD 3.0 database. Of the 207 isolates tested using BMD, 37 (17.9%) showed trailing and 19 (9.2%) showed insufficient growth; these were tested using AD. Also, 38 isolates (18.4%) for ciprofloxacin and 13 isolates (6.3%) for levofloxacin showed a lack of essential or categorical agreement between the Etest and BMD and were also tested by AD. By use of a combined reference method (BMD or AD), the susceptibility rates of Aerococcus urinae were 82.6% and 81.6% for ciprofloxacin and levofloxacin, respectively. Categorical agreement between GD and the combined reference methods was 95.2% for ciprofloxacin and 97.1% for levofloxacin, with no very major error identified. Major and minor error rates were 0.6% and 4.3% for ciprofloxacin and 1.2% and 1.9% for levofloxacin. Overall, antimicrobial susceptibility testing (AST) using the Etest on sheep blood agar showed good agreement with the reference methods and can be considered by clinical laboratories wishing to perform AST on Aerococcus urinae isolates.
Topics: Aerococcus; Animals; Anti-Bacterial Agents; Canada; Disk Diffusion Antimicrobial Tests; Fluoroquinolones; Microbial Sensitivity Tests; Quebec; Sheep
PubMed: 34076476
DOI: 10.1128/JCM.00259-21 -
Scientific Reports May 2021Currently, few studies are reported on the composition of microbiota in stroke patients and the association with stroke prognosis. This study investigated the differing...
Currently, few studies are reported on the composition of microbiota in stroke patients and the association with stroke prognosis. This study investigated the differing microbiota composition in stroke patients and confirmed the association of microbiota composition with poor functional outcome. Between January of 2018 and December of 2019, 198 patients with acute cerebral infarction were included in this study. For the case-control study, age and sex-matched normal healthy subjects (n = 200) were included when receiving their health screening examinations. We isolated bacterial extracellular membrane vesicles and extracted DNA from blood samples. Taxonomic assignments were performed by using the sequence reads of 16S rRNA genes following blood microbiota analysis. Statistical analysis was conducted appropriately by using Statistical Analysis System software. The mean age of the stroke patients were 63.7 ± 12.5 years, and the male sex was 58.5%. Of the total enrolled patients, poor functional outcome (modified Rankin Score ≥ 3) was noted in 19.7%. The principal component analysis of microbiota composition revealed significant differences between healthy control subjects and stroke patients. At the genus level, Aerococcaceae(f), ZB2(c), TM7-1(c), and Flavobacterium were significantly increased in stroke patients compared to the healthy controls, whereas Mucispirillum, rc4-4, Akkermansia, Clostridiales(o), Lactobacillus, and Stenotrophomonas were decreased considerably. For the functional outcome after ischemic stroke, Anaerococcus, Blautia, Dialister, Aerococcaceae(f), Propionibacterium, Microbacteriaceae(f), and Rothia were enriched in the group with good outcomes, whereas Ruminococcaceae(f) and Prevotella were enriched in the group with poor outcome. There was apparent dysbiosis of blood microbiota in patients with acute ischemic stroke compared to healthy people. Ruminococcaceae(f) and Prevotella were elevated in stroke patients with poor functional outcome.
Topics: Aged; Brain Ischemia; Dysbiosis; Feces; Humans; Ischemic Stroke; Male; Microbiota; Middle Aged
PubMed: 34040060
DOI: 10.1038/s41598-021-90463-5 -
Allergy Nov 2021Growing up on traditional, single-family farms is associated with protection against asthma in school age, but the mechanisms against early manifestations of atopic...
BACKGROUND
Growing up on traditional, single-family farms is associated with protection against asthma in school age, but the mechanisms against early manifestations of atopic disease are largely unknown. We sought determine the gut microbiome and metabolome composition in rural Old Order Mennonite (OOM) infants at low risk and Rochester, NY urban/suburban infants at high risk for atopic diseases.
METHODS
In a cohort of 65 OOM and 39 Rochester mother-infant pairs, 101 infant stool and 61 human milk samples were assessed by 16S rRNA gene sequencing for microbiome composition and qPCR to quantify Bifidobacterium spp. and B. longum ssp. infantis (B. infantis), a consumer of human milk oligosaccharides (HMOs). Fatty acids (FAs) were analyzed in 34 stool and human 24 milk samples. Diagnoses and symptoms of atopic diseases by 3 years of age were assessed by telephone.
RESULTS
At a median age of 2 months, stool was enriched with Bifidobacteriaceae, Clostridiaceae, and Aerococcaceae in the OOM compared with Rochester infants. B. infantis was more abundant (p < .001) and prevalent, detected in 70% of OOM compared with 21% of Rochester infants (p < .001). Stool colonized with B. infantis had higher levels of lactate and several medium- to long/odd-chain FAs. In contrast, paired human milk was enriched with a distinct set of FAs including butyrate. Atopic diseases were reported in 6.5% of OOM and 35% of Rochester children (p < .001).
CONCLUSION
A high rate of B. infantis colonization, similar to that seen in developing countries, is found in the OOM at low risk for atopic diseases.
Topics: Bifidobacterium longum subspecies infantis; Child; Farms; Gastrointestinal Microbiome; Humans; Infant; Life Style; Milk, Human; Oligosaccharides; RNA, Ribosomal, 16S
PubMed: 33905556
DOI: 10.1111/all.14877 -
Revista Do Instituto de Medicina... 2021We report a rare case of an infective endocarditis by Aerococcus spp in a bioprosthetic aortic valve following a prostate biopsy, in an asymptomatic adult with no...
We report a rare case of an infective endocarditis by Aerococcus spp in a bioprosthetic aortic valve following a prostate biopsy, in an asymptomatic adult with no additional risk factor for prostate cancer, excepting for age. The diagnosis was based on the presence of vegetations on the bioprosthesis seen on the echocardiogram, positive blood cultures and fever, and a favorable clinical outcome following the treatment with ceftriaxone and gentamicin.
Topics: Aerococcus; Aged; Biopsy; Ceftriaxone; Echocardiography; Endocarditis; Female; Fever; Gentamicins; Gram-Positive Bacterial Infections; Humans; Male; Prostate; RNA, Ribosomal, 16S; Treatment Outcome
PubMed: 33787738
DOI: 10.1590/S1678-9946202163018 -
Journal of Dairy Science May 2021The objective of this prospective cohort study was to explore associations between intramammary infection (IMI) in late-lactation cows and postcalving udder health and...
Postcalving udder health and productivity in cows approaching dry-off with intramammary infections caused by non-aureus Staphylococcus, Aerococcus, Enterococcus, Lactococcus, and Streptococcus species.
The objective of this prospective cohort study was to explore associations between intramammary infection (IMI) in late-lactation cows and postcalving udder health and productivity. Cows (n = 2,763) from 74 US dairy herds were recruited as part of a previously published cross-sectional study of bedding management and IMI in late-lactation cows. Each herd was visited twice for sampling. At each visit, aseptic quarter milk samples were collected from 20 cows approaching dry-off (>180 d pregnant), which were cultured using standard bacteriological methods and MALDI-TOF for identification of isolates. Quarter-level culture results were used to establish cow-level IMI status at enrollment. Cows were followed from enrollment until 120 d in milk (DIM) in the subsequent lactation. Herd records were used to establish whether subjects experienced clinical mastitis or removal from the herd, and DHIA test-day data were used to record subclinical mastitis events (somatic cell count >200,000 cells/mL) and milk yield (kg/d) during the follow-up period. Cox regression and generalized estimating equations were used to evaluate the associations between IMI and the outcome of interest. The presence of late-lactation IMI caused by major pathogens was positively associated with postcalving clinical mastitis [hazard ratio = 1.5, 95% confidence interval (CI): 1.2, 2.0] and subclinical mastitis (risk ratio = 1.5, 95% CI: 1.3, 1.9). Species within the non-aureus Staphylococcus (NAS) group varied in their associations with postcalving udder health, with some species being associated with increases in clinical and subclinical mastitis in the subsequent lactation. Late-lactation IMI caused by Streptococcus and Streptococcus (Strep)-like organisms, other than Aerococcus spp. (i.e., Enterococcus, Lactococcus, and Streptococcus spp.) were associated with increases in postcalving clinical and subclinical mastitis. Test-day milk yield from 1 to 120 DIM was lower (-0.9 kg, 95% CI: -1.6, -0.3) in late-lactation cows with any IMI compared with cows without IMI. No associations were detected between IMI in late lactation and risk for postcalving removal from the herd within the first 120 DIM. Effect estimates reported in this study may be less than the underlying quarter-level effect size for IMI at dry-off and postcalving clinical and subclinical mastitis, because of the use of late-lactation IMI as a proxy for IMI at dry-off and the use of cow-level exposure and outcome measurements. Furthermore, the large number of models run in this study (n = 94) increases the chance of identifying chance associations. Therefore, confirmatory studies should be conducted. We conclude that IMI in late lactation may increase risk of clinical and subclinical mastitis in the subsequent lactation. The relationship between IMI and postcalving health and productivity is likely to vary among pathogens, with Staphylococcus aureus, Streptococcus spp., Enterococcus spp., and Lactococcus spp. being the most important pathogens identified in the current study.
Topics: Aerococcus; Animals; Cattle; Cattle Diseases; Cell Count; Cross-Sectional Studies; Enterococcus; Female; Lactation; Lactococcus; Mammary Glands, Animal; Mastitis, Bovine; Milk; Pregnancy; Prospective Studies; Staphylococcus; Streptococcus
PubMed: 33685704
DOI: 10.3168/jds.2020-19288 -
Veterinary Medicine and Science Jul 2021Swine abortion caused by viruses as well as bacteria has caused many economic losses in domestic farms over the years; however, bacterial abortion has not yet been...
Swine abortion caused by viruses as well as bacteria has caused many economic losses in domestic farms over the years; however, bacterial abortion has not yet been studied in Korea. Several bacterial species were isolated from aborted fetuses (n = 103) for which the cause of death was not viral abortion. Among them, we focused on Aerococcus viridans, which had the highest positive rate within three provinces (Gangwon, Jeonnam and Gyeongnam). A total of 16 isolates were identified as A. viridans by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and 13 were characterized by both antibiotic resistance and 16S rRNA gene analysis. Based on antibiotic susceptibility testing result, eight antimicrobials could not effectively eliminate the present isolation (more than 40% of isolates can resist these antibiotics), while all except two strains were susceptible to trimethoprim/sulfamethoxazole. Molecular analysis indicated genetic variation among these strains. This study is the first report detecting A. viridans from aborted fetuses in Korean domestic farms.
Topics: Aerococcus; Animals; Drug Resistance, Bacterial; Farms; Genetic Variation; Gram-Positive Bacterial Infections; Microbial Sensitivity Tests; Prevalence; RNA, Bacterial; RNA, Ribosomal, 16S; Republic of Korea; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Sus scrofa; Swine; Swine Diseases
PubMed: 33624943
DOI: 10.1002/vms3.456 -
BMC Urology Dec 2020Transurethral resection of the prostate (TUR-P) is one of the most frequent routine procedures in urology. Because of the semisterile environment, postoperative...
BACKGROUND
Transurethral resection of the prostate (TUR-P) is one of the most frequent routine procedures in urology. Because of the semisterile environment, postoperative infections, including sepsis, are a common complication, with Escherichia coli, Klebsiella spp., Proteus mirabilis or Enterococcus faecalis as frequently isolated pathogens. Facklamia hominis is a gram-positive, facultatively anaerobic, alpha-hemolytic, catalase-negative coccus that was first described in 1997. To date, only a few cases of infectious complications have been described. We report the first case of postoperative bacteremia due to Facklamia hominis after TUR-P.
CASE PRESENTATION
An 82-year-old man developed fever only a few hours after elective TUR-P because of benign prostate syndrome. After cultivation of blood cultures, antibiotic therapy with ceftriaxone was intravenously administered and changed to oral cotrimoxazole before discharge of the afebrile patient. One anaerobic blood culture revealed Facklamia hominis. Under antibiotic therapy, the patient remained afebrile and showed no signs of infections during follow-up.
CONCLUSIONS
Fever and bacteremia are frequent complications after TUR-P. This study is the first report of Facklamia hominis in a postoperative blood culture after TUR-P. To date, there are only a few reports of patients with infectious complications and isolation of Facklamia hominis in various patient samples. Because Facklamia hominis resembles viridans streptococci on blood agar analysis, this pathogen may often be misidentified. In this case identification of Facklamia hominis was possible with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. It has been postulated that Facklamia hominis might be a facultative pathogen and that its incidence will increase in the future.
Topics: Aerococcaceae; Aged, 80 and over; Bacteremia; Gram-Positive Bacterial Infections; Humans; Male; Postoperative Complications; Transurethral Resection of Prostate
PubMed: 33287796
DOI: 10.1186/s12894-020-00762-8