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Medicine Apr 2019With increasing rates of device implantation, there is an increased recognition of device infection. We conducted a retrospective observational study in a tertiary care... (Observational Study)
Observational Study
With increasing rates of device implantation, there is an increased recognition of device infection. We conducted a retrospective observational study in a tertiary care center in Lebanon, with data collected from medical records of patients presenting with cardiac implantable electronic device (CIED) infection from 2000 to 2017 with the purpose of identifying etiologies, risk factors and other parameters, and comparing them to available data from the rest of the world. We identified a total of 22 CIED infections. The most common microbial etiologies, including involvement in polymicrobial infection, were coagulase-negative staphylococci (45.5%) and Staphylococcus aureus (22.7%). Rare cases of Brucella melitensis, Sphingomonas paucimobilis, and Kytococcus schroeteri device infection were seen. Heart failure was seen in 77.3% of patients, hypertension in 68.2%, and chronic kidney disease in 50%. Skin changes were the most common presenting symptoms (86.4%). Antibiotics were given to all patients and all had their devices removed, with 36.4% undergoing new device implantation. This is the first study of CIED infections in Lebanon and the Middle East. Local epidemiology and occupational exposure must be considered while contemplating the microbial etiology of infection. Close monitoring after device implantation is important in preventing device infection that carries high risk of morbidity and mortality.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Defibrillators, Implantable; Female; Humans; Infant; Lebanon; Male; Medical Records; Middle Aged; Pacemaker, Artificial; Prosthesis-Related Infections; Retrospective Studies; Risk Factors; Staphylococcal Infections; Staphylococcus aureus; Young Adult
PubMed: 31008922
DOI: 10.1097/MD.0000000000014906 -
Biotechnology Advances Nov 2019Lignin is one of the most abundant renewable resources on earth and is readily produced as a sidestream during biomass fractioning. So far, these large quantities of... (Review)
Review
Lignin is one of the most abundant renewable resources on earth and is readily produced as a sidestream during biomass fractioning. So far, these large quantities of lignin have been severely underutilized, thereby wasting this valuable renewable. Recent technological advances in lignin recovery, breakdown, and conversion have now started forming the first sustainable value chains to take advantage of lignin. Microbial cell factories, inspired by nature's miscellaneous set of lignin-degrading microbes, are at the heart of these novel processes. Recent success stories in which the enzymes and pathways of these microbes were harnessed for biobased production from lignin hold great promise for a sustainable upgrading of this renewable polymer into value-added compounds.
Topics: Biomass; Delivery of Health Care; Lignin
PubMed: 30959173
DOI: 10.1016/j.biotechadv.2019.02.016 -
Journal of Lipid Research May 2019Isotope labels are frequently used tools to track metabolites through complex biochemical pathways and to discern the mechanisms of enzyme-catalyzed reactions.... (Comparative Study)
Comparative Study
Isotope labels are frequently used tools to track metabolites through complex biochemical pathways and to discern the mechanisms of enzyme-catalyzed reactions. Isotopically labeled l-serine is often used to monitor the activity of the first enzyme in sphingolipid biosynthesis, serine palmitoyltransferase (SPT), as well as labeling downstream cellular metabolites. Intrigued by the effect that isotope labels may be having on SPT catalysis, we characterized the impact of different l-serine isotopologues on the catalytic activity of recombinant SPT isozymes from humans and the bacterium Our data show that SPT activity displays a clear isotope effect with [2,3,3-D]l-serine, whereas the human SPT isoform does not. This suggests that although both human and SPT catalyze the same chemical reaction, there may well be underlying subtle differences in their catalytic mechanisms. Our results suggest that it is the activating small subunits of human SPT that play a key role in these mechanistic variations. This study also highlights that it is important to consider the type and location of isotope labels on a substrate when they are to be used in in vitro and in vivo studies.
Topics: Humans; Isotope Labeling; Kinetics; Microsomes; Serine; Serine C-Palmitoyltransferase; Sphingomonas; Substrate Specificity
PubMed: 30792183
DOI: 10.1194/jlr.M089367 -
International Journal of Microbiology 2018Certain rhizobacteria can be applied to remove arsenic in the environment through bioremediation or phytoremediation. This study determines the minimum inhibitory...
Certain rhizobacteria can be applied to remove arsenic in the environment through bioremediation or phytoremediation. This study determines the minimum inhibitory concentration (MIC) of arsenic on identified rhizobacteria that were isolated from the roots of (Jacq.) Raven. The arsenic biosorption capability of the was also analyzed. Among the 10 isolated rhizobacteria, five were Gram-positive (, , and ), and five were Gram-negative ( spp., and ). showed the highest MIC of >1,500 mg/L of arsenic. All the rhizobacteria were capable of absorbing arsenic, and showed the highest arsenic biosorption capability (146.4 ± 23.4 mg/g dry cell weight). Kinetic rate analysis showed that followed the pore diffusion model ( = 0.86), followed the pseudo-first-order kinetic model ( = 0.99), and followed the pseudo-second-order kinetic model ( = 0.93). The identified rhizobacteria differ in their mechanism of arsenic biosorption, arsenic biosorption capability, and kinetic models in arsenic biosorption.
PubMed: 30723505
DOI: 10.1155/2018/3101498 -
Journal of Veterinary Research Sep 2018Changes occurring in freshwater ecosystems seem to be fundamental in the development of all microorganisms, including those pathogenic to fish. This has been especially...
Changes occurring in freshwater ecosystems seem to be fundamental in the development of all microorganisms, including those pathogenic to fish. This has been especially evident in recent years during which dynamic variations in bacterial fish pathology have been observed. Gram-negative bacteria commonly known to be pathogenic to fish, like spp., spp., spp., and are replaced by other species, which until now have not been known to be virulent or even conditionally pathogenic to fish. Nowadays, among these other species spp., , , and are the most frequently isolated from fish exhibiting clinical signs of disease. Two Gram-positive bacteria have become pathogens of particular importance in fish pathology in Poland: and . In addition, infections caused by the Gram-positive bacterium have appeared in recent years. This bacterium has not been known until now to be pathogenic to fish. Therefore, this infection could be called an emergent disease.
PubMed: 30584602
DOI: 10.2478/jvetres-2018-0037 -
Oman Journal of Ophthalmology 2018We describe a case of a man with neurotrophic keratitis of unknown ethiology, who developed a massive stromal melting during treatment of a persistent epithelial defect....
We describe a case of a man with neurotrophic keratitis of unknown ethiology, who developed a massive stromal melting during treatment of a persistent epithelial defect. A tectonic keratoplasty combined with amniotic membrane grafting was made. Host cornea specimen was analyzed, and Sphingomonas paucimobilis was isolated.
PubMed: 30505128
DOI: 10.4103/ojo.OJO_98_2017 -
International Journal of Infectious... Dec 2018Sphingomonas paucimobilis is an emerging opportunistic bacterium with a particular tropism toward bones and soft tissues. It is a gram-negative rod that can infect...
BACKGROUND
Sphingomonas paucimobilis is an emerging opportunistic bacterium with a particular tropism toward bones and soft tissues. It is a gram-negative rod that can infect immunosuppressed or immunocompetent individuals in the community or hospital settings. Prognosis of infected patients is generally good, but morbidity and mortality cases have both been documented.
OBJECTIVES
To present and discuss all reported Sphingomonas paucimobilis-mediated bone and soft-tissue infections, and shed light upon the relevance of this organism in orthopaedic surgery.
DATA SOURCES
Pubmed and Cochrane Library.
STUDY ELIGIBILITY CRITERIA
Studies reporting at least one human bone or soft-tissue infection due to Sphingomonas paucimobilis.
RESULTS
Ten articles describing 19 patients met the inclusion criteria. Common infections included osteomyelitis, cellulitis, and septic arthritis. Fifteen patients (78.9%) had community-acquired diseases. All patients were successfully treated with antibiotic therapy and only one (5.3%) had a residual complication.
LIMITATIONS
The study included a small sample size presenting with bone or soft-tissue infections. Some cases had lacking data.
CONCLUSION
Despite being associated with a good prognosis in most cases, Sphingomonas paucimobilis-related orthopaedic infections may exhibit some complications.
Topics: Anti-Bacterial Agents; Bone Diseases, Infectious; Gram-Negative Bacterial Infections; Humans; Immunocompromised Host; Morbidity; Soft Tissue Infections; Sphingomonas
PubMed: 30267938
DOI: 10.1016/j.ijid.2018.09.021 -
Journal of Inorganic Biochemistry Nov 2018The CYP152 family of cytochrome P450 enzymes (P450s or CYPs) are bacterial peroxygenases that use hydrogen peroxide to drive hydroxylation and decarboxylation of fatty...
The CYP152 family of cytochrome P450 enzymes (P450s or CYPs) are bacterial peroxygenases that use hydrogen peroxide to drive hydroxylation and decarboxylation of fatty acid substrates. We have expressed and purified a novel CYP152 family member - CYP152K6 from the methylotroph Bacillus methanolicus MGA3. CYP152K6 was characterized using spectroscopic, analytical and structural methods. CYP152K6, like its peroxygenase counterpart P450 (CYP152B1) from Sphingomonas paucimobilis, does not undergo significant fatty acid-induced perturbation to the heme spectrum, with the exception of a minor Soret shift observed on binding dodecanoic acid. However, CYP152K6 purified from an E. coli expression system was crystallized and its structure was determined to 1.3 Å with tetradecanoic acid bound. No lipids were present in conditions used for crystallogenesis, and thus CYP152K6 must form a complex by incorporating the fatty acid from E. coli cells. Turnover studies with dodecanoic acid revealed several products, with 2-hydroxydodecanoic acid as the major product and much smaller quantities of 3-hydroxydodecanoic acid. Secondary turnover products were undec-1-en-1-ol, 2-hydroxydodec-2-enoic acid and 2,3-dihydroxydodecanoic acid. This is the first report of a 2,3-hydroxylated fatty acid product made by a peroxygenase P450, with the dihydroxylated product formed by CYP152K6-catalyzed 3-hydroxylation of 2-hydroxydodecanoic acid, but not by 2-hydroxylation of 3-hydroxydodecanoic acid.
Topics: Bacillus; Bacterial Proteins; Catalysis; Catalytic Domain; Crystallography, X-Ray; Cytochrome P-450 Enzyme System; Fatty Acids; Hydroxylation; Substrate Specificity
PubMed: 30119014
DOI: 10.1016/j.jinorgbio.2018.08.002 -
BMJ Case Reports Apr 2018Empyema secondary to foreign body aspiration is rare in adults. We present a case of empyema in a 77-year-old male patient related to a remote aspiration event during a...
Empyema secondary to foreign body aspiration is rare in adults. We present a case of empyema in a 77-year-old male patient related to a remote aspiration event during a dental procedure. A CT of the chest and bronchoscopy confirmed that a metallic foreign body was located within the right lower lobe bronchus. His pleural fluid culture revealed which is a low-virulent opportunistic gram-negative bacilli and rarely causes infection. The patient received meropenem followed by levofloxacin and recovered uneventfully. The attempt of foreign body removal was failed due to chronic inflammation, and the patient refused further surgical management.
Topics: Aged; Anti-Bacterial Agents; Bronchoscopy; Empyema, Pleural; Foreign Bodies; Gram-Negative Bacterial Infections; Humans; Levofloxacin; Lung; Male; Meropenem; Respiratory Aspiration; Sphingomonas; Thienamycins; Tomography, X-Ray Computed
PubMed: 29643137
DOI: 10.1136/bcr-2017-223591 -
Acta Medica Portuguesa Feb 2018The emphysematous pyelonephritis is a uncommon and potentially fatal entity. The recognition of this condition enables the early correct management of patients. Diabetes...
The emphysematous pyelonephritis is a uncommon and potentially fatal entity. The recognition of this condition enables the early correct management of patients. Diabetes and ureteral obstruction are the main risk factors identified. We present the case of a patient with no relevant risk factors or prior medical history, in which the reason of admission to the emergency department was back pain, eventually evolving into septic shock in the early hours. The imaging tests identified the presence of peri-renal and subcutaneous gas which guided the medical team to the right diagnosis (emphysematous pyelonephritis secondary to fistulized urothelial neoplasia) and the optimal surgical treatment. However, in the post-operative period the patient died, as the clinical condition and laboratory test results performed during the admission were predicting. It should also be mentioned that this same case illustrated a bacteraemia by Sphingomonas Paucimobilis (acquired in the community) with cavitated damage to lungs (probable septic embolism).
Topics: Colonic Diseases; Emphysema; Fatal Outcome; Female; Humans; Intestinal Fistula; Kidney Diseases; Kidney Neoplasms; Middle Aged; Pyelonephritis; Urinary Fistula
PubMed: 29596773
DOI: 10.20344/amp.8869