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Medicine Jun 2024In Algeria, the issue of antibiotic resistance is on the rise, being the Staphylococcus aureus infection as a significant concern of hospital-acquired infections. The... (Observational Study)
Observational Study
In Algeria, the issue of antibiotic resistance is on the rise, being the Staphylococcus aureus infection as a significant concern of hospital-acquired infections. The emergence of antibiotic resistance in this bacterium poses a worldwide challenge. The aim of this study aims to establish the incidence of S aureus strains in Algeria as well as identify phenotypic and genotypic resistance based on the "mecA" and "nuc" genes. From 2014 to 2017, a total of 185 S aureus strains were isolated from patients at a hospital in the city of Rouïba, Algiers the number of isolates was slightly higher in males at 58.06% compared to females at 41.94%, resulting in a sex ratio of 1.38. the Oxacillin and Cefoxitin DD test (1 μg oxacillin disk and 30 μg cefoxitin disk) identified 42 strains as resistant. The results indicated high resistance to lactam antibiotics, with penicillin having a 100% resistance rate. There was also significant resistance to oxacillin (51.25%) and cefoxitin (50%). This resistance was frequently associated with resistance to other antibiotic classes, such as aminoglycosides (50%) and Macrolides (28.29%). To confirm methicillin-resistant characteristics, a polymerase chain reaction (PCR) multiplex was conducted on 10 isolates (6 SARM; 4 MSSA) on a phenotypic level. Three isolates tested positive for "mecA," while 7 were negative. All strains carry the nuc gene, which is specific to S aureus. In Algeria, the incidence of S aureus resistance is slightly lower compared to other countries, but it is increasing over time. It is now more crucial than ever to restrict the proliferation of multidrug-resistant strains and reduce undue antibiotic prescriptions. To achieve this, it is vital to keep updated on the epidemiology of this bacterium and its antibiotic susceptibility. This will enable the formulation of appropriate preventive control measures to manage its progression.
Topics: Humans; Anti-Bacterial Agents; Female; Male; Staphylococcus aureus; Staphylococcal Infections; Algeria; Prevalence; Microbial Sensitivity Tests; Bacterial Proteins; Oxacillin; Adult; Penicillin-Binding Proteins; Cefoxitin; Middle Aged; Micrococcal Nuclease; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Methicillin-Resistant Staphylococcus aureus
PubMed: 38875387
DOI: 10.1097/MD.0000000000038562 -
Science Advances Jun 2024Knowledge of the nucleosynthetic isotope composition of the outermost protoplanetary disk is critical to understand the formation and early dynamical evolution of the...
Knowledge of the nucleosynthetic isotope composition of the outermost protoplanetary disk is critical to understand the formation and early dynamical evolution of the Solar System. We report the discovery of outer disk material preserved in a pristine meteorite based on its chemical composition, organic-rich petrology, and N-rich, deuterium-rich, and O-poor isotope signatures. We infer that this outer disk material originated in the comet-forming region. The nucleosynthetic Fe, Mg, Si, and Cr compositions of this material reveal that, contrary to current belief, the isotope signature of the comet-forming region is ubiquitous among outer Solar System bodies, possibly reflecting an important planetary building block in the outer Solar System. This nucleosynthetic component represents fresh material added to the outer disk by late accretion streamers connected to the ambient molecular cloud. Our results show that most Solar System carbonaceous asteroids accreted material from the comet-forming region, a signature lacking in the terrestrial planet region.
PubMed: 38875339
DOI: 10.1126/sciadv.adp1613 -
Turkish Neurosurgery Aug 2023An important complication of the anterior approach to the lower lumbar spine is vascular injury. Arterial and venous vasculature varies in size and origin, which may...
AIM
An important complication of the anterior approach to the lower lumbar spine is vascular injury. Arterial and venous vasculature varies in size and origin, which may limit the surgical zone and compromise the safety under specific circumstances. We aimed to explore the relationship between the retroperitoneal vasculature and anterior surface of the lower spine and establish values to aid in predicting the pertinence of anterior approach for the intervertebral disks at the L4-L5 and L5-S1 levels.
MATERIAL AND METHODS
The study included 13 fresh human cadavers. After exploration of the abdominal cavity and removal of the visceral organs, the vasculature, and anterior spinal surface were revealed beneath the lower extension of the perirenal fascia. Morphometric measurements of the great vessels and the intervertebral disks were obtained. All measurements were analyzed and presented as mean and standard deviation. Differences in the values between sexes were assessed.
RESULTS
The anterior height of the L4-L5 and L5-S1 intervertebral disk was 6.8 ± 0.81 mm and 6.7 ± 0.99 mm, respectively. The widths of the aorta, inferior vena cava, right and left common iliac arteries, and right, and left common iliac veins were 16.4 ± 3.58, 20.6 ± 3.36, 11.5 ± 2.32, 11.5 ± 2.43, 14.7 ± 3.13, and 15.5 ± 3.27 mm, respectively. The mean aortic bifurcation angle was 45.5°. The aortic bifurcation was located above the lower endplate of the L4 vertebrae in 53.8% of the cadavers. The area of the interarterial and interiliac trigones was 14.6 ± 5.33 cm2 and 7.1 ± 4.35 cm2, respectively. No statistically significant differences were noted between the sexes.
CONCLUSION
An elaborate radiological examination of the vasculature should be performed prior to surgery to avoid unwanted vascular complications during the anterior approach. Knowing the area of the interarterial and interiliac triangles and the aortic bifurcation location could be aid in assessing the safe working zone.
PubMed: 38874242
DOI: 10.5137/1019-5149.JTN.43447-23.2 -
Cureus May 2024Background and objective Bloodstream infections (BSIs) due to multidrug-resistant Gram-negative bacteria (MDR-GNB) pose a significant global health threat amid rising...
Background and objective Bloodstream infections (BSIs) due to multidrug-resistant Gram-negative bacteria (MDR-GNB) pose a significant global health threat amid rising antimicrobial resistance (AMR). This study aimed to investigate the efficacy of ceftazidime-avibactam (CZA) as a therapeutic option for these infections, addressing the urgent need for novel treatments. Materials and methods This study was conducted over one year in the Department of Microbiology, JSS Medical College and Hospital, Mysuru, India, and employed a laboratory-based prospective design. From a total of 376 positive blood cultures, 147 multidrug-resistant (MDR) organisms were identified, and 100 were randomly selected for final analysis. Susceptibility testing via disk diffusion and minimum inhibitory concentration (MIC) determination was performed to evaluate CZA efficacy. Results was the predominant (78%) organism among the subsets, with varying susceptibility patterns observed across species. The overall CZA susceptibility was 45%, with significant discrepancies between disk diffusion and gold standard testing. Notably, there was limited efficacy against Conclusions This study underscores the pressing need for reliable testing methods and novel treatment strategies in combating MDR infections. Further research with larger sample sizes is imperative to validate our findings and guide clinicians effectively in addressing this critical health challenge.
PubMed: 38872698
DOI: 10.7759/cureus.60235 -
Mathematical Biosciences and... Mar 2024Glaucoma is a chronic neurodegenerative disease that can result in irreversible vision loss if not treated in its early stages. The cup-to-disc ratio is a key criterion...
Glaucoma is a chronic neurodegenerative disease that can result in irreversible vision loss if not treated in its early stages. The cup-to-disc ratio is a key criterion for glaucoma screening and diagnosis, and it is determined by dividing the area of the optic cup (OC) by that of the optic disc (OD) in fundus images. Consequently, the automatic and accurate segmentation of the OC and OD is a pivotal step in glaucoma detection. In recent years, numerous methods have resulted in great success on this task. However, most existing methods either have unsatisfactory segmentation accuracy or high time costs. In this paper, we propose a lightweight deep-learning architecture for the simultaneous segmentation of the OC and OD, where we have adopted fuzzy learning and a multi-layer perceptron to simplify the learning complexity and improve segmentation accuracy. Experimental results demonstrate the superiority of our proposed method as compared to most state-of-the-art approaches in terms of both training time and segmentation accuracy.
Topics: Deep Learning; Humans; Optic Disk; Glaucoma; Algorithms; Fuzzy Logic; Neural Networks, Computer; Image Processing, Computer-Assisted; Reproducibility of Results; Image Interpretation, Computer-Assisted; Fundus Oculi
PubMed: 38872528
DOI: 10.3934/mbe.2024225 -
Journal of Microbiological Methods Jun 2024Recently, considerable uncertainty has arisen concerning the appropriate susceptibility testing for cefiderocol in gram-negative bacilli, particularly in the context of...
Recently, considerable uncertainty has arisen concerning the appropriate susceptibility testing for cefiderocol in gram-negative bacilli, particularly in the context of its application to Acinetobacter spp. The optimal method for assessing the susceptibility levels of Acinetobacter spp. to cefiderocol remains a subject of debate due to substantial disparities observed in the values obtained through various testing procedures. This study employed four minimum inhibitory concentration (MIC) methodologies and the disk diffusion to assess the susceptibility of twenty-seven carbapenem resistant (CR)-Acinetobacter strains to cefiderocol. The results from our study reveal significant variations in the minimum inhibitory concentration (MIC) values obtained with the different methods and in the level of agreement in interpretation categories between the different MIC methods and the disk diffusion test. Among the MIC methods, there was relatively more consistency in reporting the interpretation categories. For European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints, the categorical agreement (CA) for MIC methods ranged between 66.7 and 81.5%. On the other hand, the essential agreement (EA) values were as low as 18.5-29.6%. The CA between MIC methods and disk diffusion was 81.5%. These results emphasize the need for a reliable, accurate, and clinically validated methodology to effectively assess the susceptibility of Acinetobacter spp. to cefiderocol. The wide variability observed in our study highlights the importance of standardizing the susceptibility testing process for cefiderocol to ensure consistent and reliable results for clinical decision-making.
PubMed: 38871227
DOI: 10.1016/j.mimet.2024.106972 -
Nanomaterials (Basel, Switzerland) May 2024Ensuring the stable operation of proton exchange membrane fuel cells is conducive to their real-world application. A promising direction for stabilizing electrodes is...
Ensuring the stable operation of proton exchange membrane fuel cells is conducive to their real-world application. A promising direction for stabilizing electrodes is the stabilization of the ionomer via the formation of surface compounds with graphene. A comprehensive study of the (electrochemical, chemical, and thermal) stability of composites for fuel cell electrodes containing a modifying additive of few-layer graphene was carried out. Electrochemical stability was studied by cycling the potential on a disk electrode for 5000 cycles. Chemical stability was assessed via the resistance of the composites to HO treatment using ion-selective potentiometry. Thermal stability was studied using differential thermal analysis. Composites were characterized by UV-Vis spectroscopy, Raman spectroscopy, EDX, and SEM. It was shown that graphene inhibits Nafion degradation when exposed to heat. Contrariwise, Nafion is corrosive to graphene. During electrochemical and chemical exposure, the determining change for carbon-rich composites is the carbon loss (oxidation) of the carbon material. In the case of carbon-poor composites, the removal of fluorine and sulfur from the Nafion polymer with their partial replacement by oxygen prevails. In all cases, the F/S ratio is stable. The dispersity of Nafion in a sample affects its chemical stability more than the G/Nafion ratio does.
PubMed: 38869547
DOI: 10.3390/nano14110922 -
Heliyon Jun 2024The increasing emergence of as the primary causative agent of otitis externa has been noted; however, detailed information regarding the molecular characteristics of...
The increasing emergence of as the primary causative agent of otitis externa has been noted; however, detailed information regarding the molecular characteristics of these strains in Iran remains scarce. The current study aims to investigate both genotypic and phenotypic attributes of strains implicated in ear infections. In the present work, we analyzed 60 strains isolated from cases of otitis externa over a period of 45 months. The resistance patterns were determined using disk diffusion and microbroth dilution methods. All isolates were confirmed by the polymerase chain reaction assay, and their biofilm production was assessed by a microtiter plate assay. Molecular characterization of the isolates was performed using the staphylococcal cassette chromosome multilocus sequence typing, and staphylococcus protein A typing methods. Overall, the results indicated that 44 out of 60 isolates (73.3 %) were methicillin-resistant . Resistance to mupirocin and vancomycin was observed in 13.3 % and 1.7 % of the tested isolates, respectively. Furthermore, out of the 60 isolates, 56 strains (93.4 %) were classified as positive biofilm strains at different levels. Twelve distinct clonal lineages were identified. The vast majority of isolates belonged to CC30/ST30-MRSA IV/t019 (41.7 %). Among the 31 strong biofilm producers, the majority (64.5 %) belonged to CC30/ST30-MRSA IV/t019 clone. Biofilm negative isolates belonged to CC22/ST22 (2 isolates), CC8/ST585 (one isolate), and CC8/ST8 (one isolate). Our result revealed that about three-quarters of PVL-positive strains belonged to CC30/ST30. Our data confirmed the presence of MSSA strains among CC30/ST30 and CC22/ST22 isolates. The mupirocin resistant isolates (n = 8) belonged to CC8/ST585-MRSA III/t713 (37.5 %), CC8/ST239-MRSA III/t030 (25 %), CC8/ST8-MRSA IV/t008 (12.5 %), CC8/ST239-MRSA III/t037 (12.5 %), and CC22/ST22-MRSA IV/t790 (12.5 %) lineages. The VRSA strain belonged to the CC8/ST8-MRSA IV/t008 lineage, carrying the determinant. iMLS phenotypes (n = 14) were distributed across different lineages, including CC30/ST30-MRSA IV/t019 (21.5 %), CC30/ST30-MSSA/t021 (21.5 %), CC22/ST22-MSSA/t005 (14.3 %), CC8/ST239-MRSA III/t030 (14.3 %), CC22/ST22-MSSA/t1869 (7.1 %), CC22/ST22-MRSA IV/t790 (7.1 %), CC8/ST239-MRSA III/t037 (7.1 %), and CC1/ST772-MRSA IV/t10795 (7.1 %). These findings highlight significant genotypic diversity and high biofilm formation among our isolates. The frequent occurrence of the CC/ST30 clone in strains isolated from otitis externa reflects the emergence of these lineages as a predominant clone in Iran, posing a significant public health concern.
PubMed: 38868027
DOI: 10.1016/j.heliyon.2024.e32002 -
Heliyon Jun 2024Lactic acid bacteria (LAB) are utilized as a starter culture in the manufacturing of fermented dairy items, as a preservative for various food products, and as a...
BACKGROUND
Lactic acid bacteria (LAB) are utilized as a starter culture in the manufacturing of fermented dairy items, as a preservative for various food products, and as a probiotic. In our country, some research has been carried out, even if LAB plays a principal role in food preservation and improves the texture and taste of fermented foods, that is why we tried to evaluate their probiotic effect. The objective of this research was to determine the antibacterial activity of ) against () ATCC 29213, investigate their antioxidant activity, and characterize their sensitivity against 18 antibiotics.
METHODS
A total of 23 LAB ( subsp. subsp. subsp. ) were isolated from cow's raw milk. The antibacterial activity was performed using two techniques, competition for nutrients and a technique utilizing components nature, using the disk diffusion method. The sensitivity of the studied LAB to different antibiotics was tested on Man rogosa sharp (MRS) agar using commercial antibiotic disks. All strains of LAB were examined for their antioxidant activity. The antioxidant activity of was tested by 2,2-diphenyl-1 picrylhydrazyl (DPPH).
RESULTS
The results showed that the MRS medium was more adapted than Muller Hinton Agar (MHA) to investigate the antibacterial activity of against ATCC 29213. Also, exhibited a notable degree of antibacterial activity against ATCC 29213. subsp. displayed higher antibacterial activities, followed by ssp. and lastly ssp. against ATCC 29213. Lc 26 among all strains of showed a high potential antibacterial activity reaching 40 ± 3 mm against ATCC 29213. All strains of showed a slightly moderate antioxidant activity (10.56 ± 1.28%-26.29 ± 0.05 %). The results of the antibiotic resistance test indicate that all strains of were resistant to cefotaxime, sulfamethoxazole-trimethoprim, and streptomycin and were sensitive to Ampicillin, Amoxicillin, Penicillin G, Teicoplanin, Vancomycin, Gentamicin 500, Tetracycline, and Chloramphenicol. These test results indicate that this strain falls within the criteria of not posing any harmful effects on human health. The important antibacterial properties recorded for all strains were derived from the production of antibacterial active metabolites, such as protein, diacetyl, hydrogen peroxide, and lactic acid, together with the fight for nutrients.
CONCLUSION
This study suggests that the strains of could be added as an antibacterial agent against ATCC 29213 and can provide an important nutritional property for their antioxidant potential.
PubMed: 38867975
DOI: 10.1016/j.heliyon.2024.e31957 -
Scientific Reports Jun 2024The disc overhang diameter can significantly affect the uplift bearing capacity of new concrete expanded-plate pile groups, affecting their design and practical...
The disc overhang diameter can significantly affect the uplift bearing capacity of new concrete expanded-plate pile groups, affecting their design and practical applications. Accordingly, this effect was investigated considering the failure laws of the soil surrounding various pile types and groups. Based on the uplift bearing capacities of single and double piles, a finite element simulation was adopted to establish models for the four-, six-, and nine-pile groups. The relationship between the disc overhang diameter and uplift-bearing capacity of each pile group was explored: as the disk overhang diameter increased, the uplift-bearing capacities of the pile groups increased; however, this relationship is nonlinear. The optimal disc overhang diameter was determined as 1.5-1.75 times the pile diameter. For a constant disc overhang diameter, corner piles have a greater uplift bearing capacity than side piles in the six-pile group, and a greater uplift bearing capacity than the side and center piles in the nine-pile group. Thus, the pile-group effect depends on the pile position. The uplift bearing capacity did not increase linearly with the number of piles, and the average uplift bearing capacity of a pile in a pile group was less than that of a single pile. Therefore, the uplift bearing capacity of the pile groups decreased as the number of piles increased. The reliability of the simulation was verified via visual testing of a small-scale half-cut pile model.
PubMed: 38867072
DOI: 10.1038/s41598-024-64504-8