Rapid detection and quantification of Propionibacteriaceae

Protective effects of sulforaphane on inflammation, oxidative stress and intestinal dysbacteriosis induced by triphenyltin in Cyprinus carpio haematopterus

The purpose of this experiment was to study the mitigation effect of sulforaphane (SFN) on fish toxicological damage caused by triphenyltin (TPT) pollution. A total of 320 healthy fish (56.9 ± 0.4g) were randomly placed into four groups, each with four duplicates. The control group was fed the basal diet, the TPT group was exposed to 10 ng/L TPT on the basis of the control group, the SFN group was fed a diet supplemented with 10 mg/kg SFN, the SFN + TPT group was exposed to 10 ng/L TPT on the basis of the SFN group. Each tank had 20 fish and the breeding lasted for 8 weeks. The present study found that the antioxidant enzyme activity in the TPT group was significantly lower than that of the control group (P < 0.05). In addition, compared with the control group, the mRNA expression of pro-inflammatory factors (IL-6, TNF-α) were significantly induced, and the anti-inflammatory factor genes (IL-10, TGF) were significantly inhibited (P < 0.05) in TPT group. SFN relieved the changes of inflammatory factors caused by TPT, ameliorated oxidative stress, improved antioxidant enzyme (include SOD, CAT, GSH, GPx) activities (P < 0.05). 16s RNA analysis indicated that exposure to TPT caused changes in intestinal microflora. The results of the study showed that after exposure to TPT, some beneficial genera of bacteria in the gut of Rhizobiaceae, Bdellovibrio and Candidatus Alysiosphaera were decreased. The bacteria associated with intestinal inflammation including Propionibacterium, Rubrobacter, Anaerorhabdus_furcosa_group, Rikenellaceae and Eubacterium_brachy were upregulated. However, the SFN treatment group significantly down-regulated the above five inflammation-related bacteria. The above results indicated that TPT caused oxidative stress and inflammation in fish intestines, changed the intestinal microflora, and dietary SFN could improve antioxidant status, regulate inflammation and intestinal health. Therefore, SFN is a promising diet additive for improving fish damage caused by TPT contamination.

Ambient particulate air pollution and the intestinal microbiome; a systematic review of epidemiological, in vivo and, in vitro studies

A healthy indigenous intestinal microbiome is indispensable for intra- and extra-intestinal human health. Since well-established factors such as diet and antibiotic use only explain 16 % of the inter-individual variation in gut microbiome composition, recent studies have focused on the association between ambient particulate air pollution and the intestinal microbiome. We systematically summarize and discuss all evidence concerning the effect of particulate air pollution on intestinal bacterial diversity indices, specific bacterial taxa, and potential underlying intestinal mechanisms. To this end, all possibly relevant publications published between February 1982 and January 2023 were screened, and eventually, 48 articles were included. The vast majority (n = 35) of these studies were animal studies. The exposure periods investigated in the human epidemiological studies (n = 12) ranged from infancy through elderly. This systematic review found that intestinal microbiome diversity indices were generally negatively associated with particulate air pollution in epidemiological studies, with an increase in taxa belonging to Bacteroidetes (two studies), Deferribacterota (one study), and Proteobacteria (four studies), a decrease in taxa belonging to Verrucomicrobiota (one study), and no consensus for taxa belonging to Actinobacteria (six studies) and Firmicutes (seven studies). There was no unequivocal effect of ambient particulate air pollution exposure on bacterial indices and taxa in animal studies. Only one study in humans examined a possible underlying mechanism; yet, the included in vitro and animal studies depicted higher gut damage, inflammation, oxidative stress, and permeability in exposed versus unexposed animals. Overall, the population-based studies showed a dose-related continuum of short- and long-term ambient particulate air pollution exposure on lower gut diversity and shifts in taxa over the entire life course.

Acute postoperative endophthalmitis: Microbiology from the laboratory to the bedside

Postoperative endophthalmitis is a dreaded complication of intraocular surgery. Acute presentations need prompt management and good knowledge of differential diagnoses. In the last 10 years, progress in direct microbial detection and identification from intraocular samples included the use of blood culture systems and, more recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, improving the rate of bacterial identification. Whatever the method used, diagnostic sensitivity is better for vitreous samples than for aqueous humor samples. Besides, molecular biology techniques have further improved the identification rate of infectious agents in intraocular samples. They also provide faster results compared to culture-based techniques. Quantitative real-time PCR (qPCR) can also determine the bacterial load in intraocular samples. Several studies have shown that intraocular bacterial loads in endophthalmitis patients are usually high, which helps differentiating infection from contamination. The prognostic value of qPCR remains to be validated. Whole genome DNA sequencing technologies facilitate direct and sequencing of single DNA molecules. They have the potential to increase the rate of microbiological identification. Some antibiotic resistance markers (e.g., methicillin resistance in staphylococci and vancomycin resistance in enterococci) may be detected earlier using molecular techniques (usually real-time PCR tests). Early determination of the involved microorganism and their antibiotic resistances can help establishing an earlier therapeutic strategy.

Fast and Sensitive Multiplex Real-Time Quantitative PCR to Detect Cutibacterium Periprosthetic Joint Infections

Diagnosis of Cutibacterium periprosthetic joint infections (PJIs) is challenging due to a long cultivation time of up to 14 days. Faster culture-independent diagnosis would improve patient care with early and accurate treatment. Specific primers and probes were designed for Cutibacterium acnes, Cutibacterium avidum, and Cutibacterium granulosum and evaluated in a multiplex TaqMan real-time quantitative PCR (qPCR) format on 57 skin swabs and 20 culture-negative cerebrospinal fluid samples. The multiplex qPCR was tested in a PJI cohort of 41 sonication fluid samples from removed implants infected with different pathogens. All five culture-positive Cutibacterium PJIs were detected with the corresponding Cutibacterium-specific probe (100% positive percent agreement). The multiplex qPCR additionally detected C. avidum in two PJI sonication fluid samples that were diagnosed as Staphylococcus species infections according to culture (95% negative percent agreement). The new multiplex qPCR can provide a Cutibacterium PJI diagnosis within 1 day, allowing early and accurate antibiotic treatment. A prospective diagnostic trial in PJI with a high number of Cutibacterium species infections (shoulder PJI) is needed for further evaluation.

An Atypical Presentation of Propionibacterium Acnes Endophthalmitis Following Cataract Surgery

Purpose:

To describe a case with an unusual presentation of Propionibacterium acnes ( P acnes) with ultimately a good visual outcome.

Methods:

A case report with review of approaches to P acnes endophthalmitis.

Results:

We describe a patient with an unusual presentation of P acnes of panuveitis with white, circular preretinal lesions without intracapsular deposits. Diagnosis was made from cultures from pars plana vitrectomy. Eventually, she was definitively managed with capsulectomy, repositioning of her intraocular lens via sutureless intrascleral fixation, and intravitreal vancomycin injection.

Conclusion:

This is a report of P acnes endophthalmitis presenting with discrete preretinal lesions where surgical and medical management lead to a complete resolution of uveitis and symptoms after a 3-year follow up where the patient’s final visual acuity was Snellen 20/20 OU.

Enzymatic treatment of specimens before DNA extraction directly influences molecular detection of infectious agents

INTRODUCTION

Biological samples, pharmaceuticals or food contain proteins, lipids, polymers, ammoniums and macromolecules that alter the detection of infectious agents by DNA amplification techniques (PCR). Moreover the targeted DNA has to be released from the complex cell walls and the compact nucleoprotein matrixes and cleared from potential inhibitors. The goal of the present work was to assess the efficiency of enzymatic pretreatments on infectious agents to make DNA available for further extraction and amplification.

METHODS

Staphylococcus epidermidis, Streptococcus mitis, Propionibacterium acnes, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger and Fusarium solani were mixed with an internal control virus and treated with: 1) proteinase K; 2) lyticase and 3) lyticase followed by proteinase K. DNAs was manually extracted using the QIAmp DNA Mini kit or the MagNA Pure Compact automate. DNA extraction yields and the inhibitors were assessed with a phocid Herpesvirus. Bacterial detection was performed using TaqMan real-time PCR and yeasts and filamentous Fungi with HRM (real-time PCR followed by high-resolution melting analysis).

RESULTS

Viral DNA was released, extracted and detected using manual and automatic methods without pre enzymatic treatments. Either the manual or the automatic DNA extraction systems did not meet the sensitivity expectations if enzymatic treatments were not performed before: lyticase for Fungi and Proteinase K for Bacteria. The addition of lyticase and proteinase K did not improve results. For Fungi the detection after lyticase was higher than for Proteinase K, for which melting analysis did not allow fungal specification.

DISCUSSION

Columns and magnetic beads allowed collecting DNA and separate PCR inhibitors. Detection rates cannot be related to DNA-avidity of beads or to elution but to the lack of proteolysis.

The microbiome extends to subepidermal compartments of normal skin

Commensal microbes on the skin surface influence the behavior of cells below the epidermis. We hypothesized that bacteria or their products exist below the surface epithelium and thus permit physical interaction between microbes and dermal cells. Here, to test this hypothesis, we employed multiple independent detection techniques for bacteria including qPCR, Gram-staining, immunofluorescence, and in situ hybridization. Bacteria were consistently detectable within the dermis and dermal adipose of normal human skin. Sequencing of DNA from dermis and dermal adipose tissue identified bacterial 16S rRNA reflective of a diverse and partially distinct microbial community in each skin compartment. These results show the microbiota extends within the dermis, therefore enabling physical contact between bacteria and various cells below the basement membrane. These observations show that normal commensal bacterial communities directly communicate with the host in a tissue previously thought to be sterile.

Chronic prostatic infection and inflammation by Propionibacterium acnes in a rat prostate infection model

Chronic inflammation in the prostate, seen as infiltration of inflammatory cells into the prostate gland in histological samples, affects approximately half the male population without indication of prostate disease, and is almost ubiquitous in patients diagnosed with benign prostate hyperplasia and cancer. Several studies have demonstrated the Gram-positive bacterium Propionibacterium acnes to be frequently present in prostate tissue from men suffering from prostate disease. P. acnes has been shown to be associated with histological inflammation in human prostatectomy specimens, and also to induce strong inflammatory response in prostate-derived tissue culture models. The present paper describes a rat model for assessment of the pathogenic potential of P. acnes in prostate. Prostate glands of Sprague Dawley rats (n = 98) were exposed via an abdominal incision and live P. acnes or, in control rats, saline were injected into the ventral and dorso-lateral lobes. Rats were sacrificed 5 days, 3 weeks, 3 months and 6 months post infection, and prostate tissue was analyzed for bacterial content and histological inflammation. Rat sera were assessed for levels of CRP and anti-P. acnes IgG. Live P. acnes could be recovered from the dorso-lateral lobes up to 3 months post infection, while the ventral lobes were cleared from bacteria at that time. In samples up to 3 months post infection, the dorso-lateral lobes exhibited intense focal inflammation. CRP and IgG levels were elevated throughout the span of the experiment, and reached maximum levels 3 weeks and 3 months post infection, respectively. We show that P. acnes have the potential to cause chronic infection in previously healthy prostate, and that the infection has potential to cause chronic histological inflammation in the infected tissue. The high prevalence of P. acnes in human prostate tissue calls for resolution of pathogenic details. The present rat model suggests that complications such as chronic inflammation may be induced by P. acnes infection.

Propionibacterium acnes delayed infection following spinal surgery with instrumentation

Propionibacterium acnes detection in culture media was previously considered a contamination but recently its infectious role was discovered in post-spinal surgery infections. P. acnes might be introduced during surgery. Its diagnosis is based on non-specific clinical signs, image indications of infection, and the conclusive microbiological sign. Furthermore, its diagnosis is difficult because of slow growth rate and low virulence, delaying its presentation. Usually, the infection is manifested after a couple of months or years. Here, a 65-year-old man presented with drainage at the site of instrumented spinal surgery performed 13 years ago. P. acnes infection was confirmed by culture with extended incubation. Our review of the literature revealed only two other reported cases of delayed P. acnes infection presenting a decade following a spinal surgery with instrumentation. This article sheds light on such delayed infections and discusses their presentation and management.

Real-time polymerase chain reaction test to discriminate between contamination and intraocular infection after cataract surgery

PURPOSE

To determine the usefulness of real-time polymerase chain reaction (PCR) assays in the diagnosis of postoperative bacterial endophthalmitis in clinically diagnosed infectious cases and to test for bacterial DNA in control samples collected from noninfected eyes.

SETTING

Federal University of São Paulo, Brazil.

DESIGN

Evaluation of diagnostic test or technology.

METHODS

This study comprised patients with clinically diagnosed infectious endophthalmitis after cataract surgery and vitreous samples (from noninflamed eyes obtained through vitrectomy) and aqueous samples (at end of phacoemulsification) from control patients at a single university setting. Universal and gram-specific real-time PCR, Gram staining, and culture were performed. Sensitivity and cycle thresholds were determined. Clinical and microbiologic data were also assessed.

RESULTS

The study evaluated 11 patients with infectious endophthalmitis (9 vitreous and 7 aqueous samples), 12 control vitreous samples, and 50 control aqueous samples. Gram and culture identified 80% and 75%, respectively, of patients with infectious endophthalmitis. Real-time PCR assays were positive in 91% of patients with a clinical diagnosis of endophthalmitis using aqueous samples, vitreous samples, or both. None of the 12 vitreous controls were positive by PCR. Two aqueous control samples were positive by real-time PCR. The cycle threshold cutoff value was 36 for universal PCR (sensitivity 93.8%; specificity 100%) and 38 for gram-specific PCR (sensitivity 93.8%; specificity 100%). Gram-positive microorganisms prevailed, and visual acuity varied according to the causative bacteria.

CONCLUSIONS

Real-time PCR provided fast and accurate diagnosis of bacterial endophthalmitis. As a quantitative technique, it may be useful in distinguishing between contamination and infection based on the cycle thresholds value.

Endogenous endophthalmitis associated with intravenous drug abuse: seven-year experience at a tertiary referral center

PURPOSE

Intravenous drug use (IVDU) is a known risk factor for endogenous endophthalmitis. Endogenous fungal endophthalmitis (EFE) is emerging as a common problem among this community. We describe the management and visual outcomes of acute IVDU-associated EFE.

METHODS

A prospective consecutive case series of 19 patients presenting with presumed acute IVDU-associated EFE from 2001 to 2007 to the Royal Victorian Eye and Ear Hospital was included. All data were collected in a standardized manner. Outcome measures included visual acuity, microbial profiles, and vitrectomy rate.

RESULTS

Nineteen cases of IVDU-associated EFE were identified. Eight of these (42%) were men, and the mean age was 32.7 years (SD ± 8.0 years). Presenting visual acuity ranged from 6/6 to perception of light, with 58% having a visual acuity of 6/48 or less at presentation. Thirteen (68.4%) were culture positive with all cultures identifying Candida species, and 52.7% underwent vitrectomy. Fifty percent of subjects overall achieved a final visual acuity of 6/18 or better. Men demonstrated improved visual acuity when compared with women (P = 0.04). Age had no effect on final acuity.

CONCLUSION

Intravenous drug use is a significant risk factor for developing EFE. Good visual outcomes can be achieved with early treatment, often with intravitreal therapy alone.

Propionibacterium acnes in capsular bag distension syndrome

We report a case of capsular bag distension syndrome that developed 6 years after uneventful phacoemulsification with implantation of a foldable, single-piece acrylic intraocular lens (IOL) (AcrySof MA60BM). Slitlamp microscopy revealed a deep anterior chamber with no flare or cells. The posterior capsular bag was distended by a homogeneous milky substance between the back of the IOL and the capsular bag. Using a pars plana approach, a 23-gauge bimanual capsulotomy and anterior vitrectomy were performed. Microbiological analysis revealed Propionibacterium acnes in the material inside the capsular bag. The postoperative period was uneventful. Four weeks after surgery, visual acuity was restored and there were no signs of intraocular inflammation. The origin of late capsular bag distension is not fully understood; it may involve an infectious component with propionibacteria. A surgical approach and removal of the potentially infectious material can be considered as an alternative to neodymium:YAG capsulotomy.

[New ultra rapid test for detection of bacteria]

INTRODUCTION

Bacteriological testing is aimed to reduce the risk of transmission of infections. However, the detection of Bacteria by culture requires from 18hours to 14 days and may produce erroneous results for fastidious species. The goal of this work was to design and validate a new tool for bacterial testing.

METHODS

The test is based on the fast real-time PCR (frt PCR). The DNA extracted from samples containing internal controls are introduced into four tubes containing primers and probes for the frt PCR. The cycling program consists in 1×at 95°C for 10min and 45×(15s at 95°C, 8s) at 52°C and 10s at 72°C.

RESULTS

The frt PCR detects 0,01 CFU/μl of Bacteria and identifies eight Genera without interferences from the environment or from fungi and with no need for melting curve analysis or additional sequencing.

DISCUSSION

The frt PCR detects and quantifies Bacteria identifying and assessing the load of Staphylococci, Streptococci, Haemophilus, Pseudomonas, Enterobacteria, Acinetobacter, Propionibacteriacae and Corynebacteria.

CONCLUSION

Cultures require at least 24hours but the new frt PCR reduces the time to 90minutes. Larger series of samples are necessary to confirm the usefulness of this new test for routine bacterial sterility controls.