Invasive slipper limpets Crepidula fornicata act like a sink, rather than source, of Vibrio spp.

A large knowledge gap exists regarding the disease profile and pathologic condition of the invasive, non-native, slipper limpet Crepidula fornicata. To help address this, we performed a yearlong health survey across two sites in South Wales UK, subtidal Swansea Bay and intertidal Milford Haven. In total, 1,800 limpets were screened systematically for haemolymph bacterial burdens using both general and vibrio-selective growth media (TSA +2% NaCl and TCBS, respectively), haemolymph (blood) inspection using microscopy, a PCR-based assay targeting Vibrio spp., and multi-tissue histology. Over 99% of haemolymph samples contained cultivable bacterial colony forming units, and 83% of limpets tested positive for the presence of vibrios via PCR (confirmed via Sanger sequencing). Vibrio presence did not vary greatly across sites, yet a strong temporal (seasonal) effect was observed - significantly higher bacterial loads during the summer. Binomial logistic regression models revealed larger (older) limpets were more likely to harbour vibrios, and the growth of bacteria on TCBS was a key predictor for PCR-based vibrio detection. Histological assessment of >340 animals revealed little evidence of inflammation, sepsis, or immune reactivity despite the gross bacterial numbers. We contend that slipper limpets are not susceptible to bacteriosis at either site surveyed, or do not to harbour vibrios known to be pathogenic to humans. The lack of susceptibility to local pathogenic bacteria may explain, in part, the invasion success of C. fornicata across this region.

Diet-induced obesity in mice impairs host defense against Klebsiella pneumonia in vivo and glucose transport and bactericidal functions in neutrophils in vitro

Obesity impairs host defense against Klebsiella pneumoniae but responsible mechanisms are incompletely understood. To determine the impact of diet-induced obesity on pulmonary host defense against K. pneumoniae, we fed 6-week-old male C57BL/6j mice a normal (ND) or high fat diet (HFD) (13% versus 60% fat, respectively) for 16 weeks. Mice were intratracheally infected with Klebsiella, assayed at 24 or 48 h for bacterial colony-forming units, lung cytokines, and leukocytes from alveolar spaces, lung parenchyma, and gonadal adipose tissue were assessed using flow cytometry. Neutrophils from uninfected mice were cultured with and without 2-deoxy-D-glucose (2-DG) and assessed for phagocytosis, killing, reactive oxygen intermediates (ROI), transport of 2-DG, and glucose transporter (GLUT1-4) transcripts, and protein expression of GLUT1 and GLUT3. HFD mice had higher lung and splenic bacterial burdens. In HFD mice, baseline lung homogenate concentrations of IL-1β, IL-6, IL-17, IFN-ɣ, CXCL2, and TNF-ɑ were reduced relative to ND mice, but following infection were greater for IL-6, CCL2, and CXCL2 and IL-1β (24 h only). Despite equivalent lung homogenate leukocytes, HFD mice had fewer intra-alveolar neutrophils. HFD neutrophils exhibited decreased Klebsiella phagocytosis and killing, and reduced ROI to heat-killed Klebsiella in vitro. 2-DG transport was lower in HFD neutrophils, with reduced GLUT1 and GLUT3 transcripts and protein (GLUT3 only). Blocking glycolysis with 2-DG impaired bacterial killing and ROI production in neutrophils from mice fed ND but not HFD. Diet-induced obesity impairs pulmonary Klebsiella clearance and augments blood dissemination by reducing neutrophil killing and ROI due to impaired glucose transport.

THERMAL BEHAVIOR IMPROVEMENT OF BIODEGRADABLE FIBER POLYMER COMPOSITES POLYLACTIC ACID (PLA)/COIR USING ACEH’S BENTONITE

Research has been conducted on the manufacture of PLA Coir Bentonite composites. This study aims to examine the effect of PLA on mechanical strength with the addition of coir and bentonite fillers from North Aceh and Central Aceh. The sample formulations used were single polymer PLA/Coir and PLA/Coir with variations of filler Bentonite Aceh Utara and Aceh Tengah with 2, 4, 6 and 8% respectively. The combination of PCa samples showed the highest bacterial colony growth rate, which was more than 100 colonies/gram during the 1 week testing period. In the PBATd filler mixture sample, the maximum bacterial test value was 65 colonies/gram and the minimum value contained in the PBAUa sample was 105 colonies/gram. The best tensile strength was obtained in the PBATc sample, namely 65 MPa. PBATd samples began to degrade at 370.15oC compared to PCa samples degraded at 280.21oC. While the PBAUa sample began to degrade at a temperature of 282.11oC. The surface structure of the PCa sample is more homogeneous because there is no bentonite filler mixture, but it is brittle and crumbles easily. For the PBATd sample, the surface structure is smoother and more homogeneous compared to the PBAUa sample.

Loss of GdpP function in Staphylococcus aureus leads to β-lactam tolerance and enhanced evolution of β-lactam resistance

Infections caused by Staphylococcus aureus are a leading cause of mortality. Treating infections caused by S. aureus is difficult due to resistance against most traditional antibiotics, including β-lactams. We previously reported the presence of mutations in gdpP among S. aureus strains that were obtained by serial passaging in β-lactam drugs. Similar mutations have recently been reported in natural S. aureus isolates that are either non-susceptible or resistant to β-lactam antibiotics. gdpP codes for a phosphodiesterase that cleaves cyclic-di-AMP (CDA), a newly discovered second messenger. In this study, we sought to identify the role of gdpP in β-lactam resistance in S. aureus . Our results showed that gdpP associated mutations caused loss of phosphodiesterase function, leading to increased CDA accumulation in the bacterial cytosol. Deletion of gdpP led to an enhanced ability of the bacteria to withstand a β-lactam challenge (two to three log increase in bacterial colony forming units) by promoting tolerance without enhancing MICs of β-lactam antibiotics. Our results demonstrated that increased drug tolerance due to loss of GdpP function can provide a selective advantage in acquisition of high-level β-lactam resistance. Loss of GdpP function thus increases tolerance to β-lactams that can lead to its therapy failure and can permit β-lactam resistance to occur more readily.

The microbial composition of the initial insult can predict the prognosis of experimental sepsis

We hypothesized that the composition of sepsis-inducing bacterial flora influences the course of fecal peritonitis in rodents. Saline or fecal suspensions with a standardized dose range of bacterial colony-forming units (CFUs) were injected intraperitoneally into Sprague–Dawley rats. The qualitative composition of the initial inoculum and the ascites was analyzed separately by MALDI-TOF mass spectrometry. Invasive monitoring was conducted in separate anesthetized groups (n = 12–13/group) after 12, 24, 48 and 72 h to determine rat-specific organ failure assessment (ROFA) scores. Death and ROFA scores peaked at 24 h. At this time, 20% mortality occurred in animals receiving a monomicrobial E. coli suspension, and ROFA scores were significantly higher in the monomicrobial subgroup than in the polymicrobial one (median 6.5; 5.0–7.0 and 5.0; 4.75–5.0, respectively). ROFA scores dropped after 48 h, accompanied by a steady decrease in ascites CFUs and a shift towards intra-abdominal monomicrobial E. coli cultures. Furthermore, we found a relationship between ascites CFUs and the evolving change in ROFA scores throughout the study. Hence, quantitatively identical bacterial loads with mono- or polymicrobial dominance lead to a different degree of sepsis severity and divergent outcomes. Initial and intraperitoneal microbiological testing should be used to improve translational research success.

EMPLOYABILITY OF ADVANCED IMAGE PROCESSING TO EFFECTIVELY COUNT AND CLASSIFY THE BACTERIAL COLONIES

Specification of Bacterial Colonies is needed in many fields, such as clinical analysis, biomedical examination for anticipation of severe illnesses, and the drug industry to avoid tainting items. Existing Bacterial Colony counter frameworks count Bacterial Colony physically, which is a tedious, less effective and dreary cycle. Henceforth, mechanization for calculating bacterial settlement was required. The proposed strategy counts these settlements naturally utilizing picture handling strategies. This strategy will give a more superior level of precision in the counting of bacterial provinces. The proposed method takes a picture of bacterial settlement and converts it into grayscale. Otsu thresholding is applied for the division of the image, further its change into a double shot. From that point onward, morphological activities are used to tidy up the picture by eliminating commotion and superfluous pixels. Distance and watershed changes are applied to double vision to make parts among covered and joint microscopic organisms. Locale properties and marking data of fragmented picture is utilized for counting of the bacterial province.

Operation Field Contamination During Intraoperative Fluoroscopy

Background: intraoperative C-arm fluoroscopy is commonly performed during traumatic orthopedic surgeries. The C-arm sterile drape is often used in cases of contamination of the operative field following postoperative infection. The aim of the present study was to investigate operation field contamination during traumatic orthopedic surgeries and evaluate the factors, especially intraoperative fluoroscopy, which affect operation field contamination. Methods: sterile 5% sheep blood Columbia agar plates were used to simulate the operation field. The C-arm was moved over the operation field in different grade clean operating rooms, simulating intraoperative fluoroscopy. The agar plates were then incubated and assessed for bacterial colony growth. Results: our results showed significant differences between the 3rd grade clean operating room and the 2nd or 1st grade clean operating rooms in the risk of operation field contamination. Nevertheless, there were no significant differences in the operation field contamination between the C-arm drape group and the control group. Conclusions: we conclude that C-arm equipment can be used without the drape during orthopedic surgeries to avoid contact with the operation field.

Evaluation of Excreta/Secreta of Lucilia sericata Larvae as a New Antibacterial Candidate for Treatment of MRSA Ocular Infection

Staphylococcus aureus is the most serious cause of bacterial keratitis in most populations. Due to the resistance of this bacteria to methicillin (MRSA), the novel antimicrobial component is required for novel treatments for keratitis. Excretions/secretions (ES) from larvae of Lucilia sericata (maggot) have antibacterial activity against a number of bacteria. Around 500 larvae were washed with 1 mL of sterile water every hour for ES development. Bactericidal activity of ES was examined by time killing assay. MRSA strain was injected intrastromal into rabbit corneas. The rabbits have been split into three categories, including artificial tear, gentamicin, and maggot ES. Following, the eyes were clinically examined by a slit lamp. This evaluation included the conjunctiva, iris, and cornea. Lastly, the cornea of rabbits was collected for bacterial colony counts. After statistical analysis by ANOVA, it was found that gentamicin and ES, significantly reduced ocular infections in rabbits. Comparisons of corneal opacity scores with Mann–Whitney U-test showed a decreasing trend of therapeutic effects as shown below: gentamicin˃ES˃control. Gentamicin and ES significantly decrease CFU (number of colony-forming units) compared with the control. The mean bacterial count (log CFU/mL) from corneal culture for ES, gentamicin, and untreated groups were 6.04, 5.0, and 8.9, respectively (P≤0.05). In conclusion, the extraction of maggot larvae is useful in treating keratitis mediated by MRSA.