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Pyogenic liver abscesses (PLAs) are serious infections in which doctors often fail in identifying the causative agent due to microbiological limitations. These limitations in detecting uncommon pathogens complicate the treatment and recovery. Molecular techniques, like massive sequencing, enable the detection of uncommon pathogens and highlight the shortcomings of traditional cultures. The aim of this work was to characterise the bacterial composition of PLAs through massive sequencing of the V3-V4 hypervariable region of the 16S rRNA gene in cases where conventional culture methods were negative. Purulent material was collected from three patients with PLAs at Hospital Juárez de México. Classical and molecular microbiological cultures were performed in parallel. Metagenomic DNA was extracted and massively sequenced (16S rRNA gene) using the Illumina MiSeq platform. A bioinformatic analysis was performed to determine the diversity at six different taxa levels and the relative abundances. The culture methods were not sufficient to detect the causative agent of the PLAs. However, the massive sequencing revealed the causative agents of the monomicrobial and polymicrobial infectious foci, with Gardnerella vaginalis, Lactobacillus iners, and Prevotella timonensis as the dominant bacteria. The massive sequencing revealed the presence of unusual pathogens that traditional culture failed to detect. There is an immediate need for molecular or comprehensive microbiological culture techniques to search for unusual bacteria in the diagnosis of PLAs. [ABSTRACT FROM AUTHOR]

Background: The current economic and social crisis in Latin America has caused migration to the USA, bringing with it Public Health challenges due to the importation of various infectious diseases. Migrants, particularly those with chronic conditions, such as HIV infection and other sexually transmitted infections (STI), are at greater risk due to pharmacological interruption and access to medical care, so the timely detection of diseases acquired during their migration, such as malaria, is crucial to avoid health complications. Objective: To outline by a multidisciplinary approach (Infectology, Parasitology, Epidemiology, molecular Biology, Venereology, and Public Health) the diagnosis and management of a male case with malaria imported to Mexican territory, HIV chronic infection, and latent syphilis. Methods: A male migrant of Venezuelan nationality attended the Clínica Especializada Condesa Iztapalapa in Mexico City for health complications. A comprehensive analysis of laboratory and molecular tests was performed to confirm HIV infection. During the STI diagnostic algorithm, latent syphilis was detected and microscopic observation of blood smears revealed parasitic forms compatible with malaria. Standard and molecular tests were applied under the operational definition for malaria cases for identification, diagnosis, and treatment. Finally, study of clinical history and migration route by questioning for the investigation of the imported case was performed. Results: The immigrant was diagnosed with HIV chronic-stage infection with interrupted antiretroviral therapy (ART), latent syphilis, and malaria by Plasmodium vivax. The ART administered was chosen based on the possible drug interaction with antimalarials and genetic barrier to the HLA-B* allele. Finally, antimicrobial therapy against syphilis was penicillin. From the analysis of the migratory route, incubation time of imported malaria, and questioning, we speculated that the migrant acquired the P. vivax infection in Panama. Conclusions: This case highlights the complex health problems faced by migrants with HIV infection, particularly when they contract additional infections such as malaria during migration and highlights the need for comprehensive access to healthcare and ART, antimalarial and antimicrobial treatments to mitigate the health risks of this vulnerable population. [ABSTRACT FROM AUTHOR]

We realize that a Sierpiński arrowhead curve (SAC) fills a Sierpiński gasket (SG) in the same manner as a Peano curve fills a square. Namely, in the limit of an infinite number of iterations, the fractal SAC remains self-avoiding, such that S A C ⊂ S G . Therefore, SAC differs from SG in the same sense as the self-avoiding Peano curve P C ⊂ 0,1 2 differs from the square. In particular, the SG has three-line segments constituting a regular triangle as its border, whereas the border of SAC has the structure of a totally disconnected fat Cantor set. Thus, in contrast to the SG, which has loops at all scales, the SAC is loopless. Consequently, although both patterns have the same similarity dimension D = ln ⁡ 3 / ln ⁡ 2 , their connectivity dimensions are different. Specifically, the connectivity dimension of the self-avoiding SAC is equal to its topological dimension d l S A C = d = 1 , whereas the connectivity dimension of the SG is equal to its similarity dimension, that is, d l S G = D . Therefore, the dynamic properties of SG and SAC are also different. Some other noteworthy features of the Sierpiński triangle are also highlighted. [ABSTRACT FROM AUTHOR]

Infections pose a risk for patients undergoing hematopoietic stem cell (HSC) transplants due to their immunosuppression, making them susceptible to opportunistic infections. Therefore, understanding the composition of the aerobiome in this area is vital. The aim of this study was to characterize the aerobiome in an HSC transplant area, evaluating the impact of infrastructure and health personnel operations on air contamination. The environmental parameters and aerobiome of the HSC transplant area at Hospital Juárez de México were quantified over one year. Finally, a double-entry Vester matrix was constructed to classify problems according to their degree of causality. The abundance and taxonomic diversity of the aerobiome were dependent on seasonality, environmental factors, and high-efficiency filtration. Gram-positive bacteria predominated, followed by fungi and Gram-negative bacteria. ANOVA revealed significant differences in the bacterial aerobiome but not in the fungal aerobiome among the transplant rooms. Clinically, fungi such as Aspergillus fumigatus, Alternaria spp., Cladosporium spp., and Penicillium spp. were identified. ESKAPE bacteria typing revealed clonal dispersion. Finally, the Vester matrix highlighted critical problems associated with contamination due to the absence of HEPA filtration and non-adherence in patient management practices. HEPA filtration and positive pressure are essential to improve the air quality and reduce the microbiological load. However, the control areas will depend on patient management and routine activities, such as entry protocols in controlled areas. [ABSTRACT FROM AUTHOR]

Particle size reduction through ball milling presents an appealing approach to enhance the energy storage properties of lithium iron phosphate used in cathodes for lithium-ion batteries. However, the impact of ball milling conditions on electronic conduction and specific storage capacities remains poorly understood. In this study, we investigated the effects of both dry and solvent-based ball milling (utilizing water, methanol, and acetone) on microstructural, electronic, and electrochemical properties. The use of water and methanol resulted in particle agglomeration, creating additional paths for electronic conduction but adversely affecting specific energy storage capacity. Conversely, the utilization of acetone reduced the formation of these agglomerates, improving electronic conduction. However, this also led to the creation of defects that hindered an enhancement in energy storage. Ultimately, dry milling emerged as the optimal method under the experimental conditions assessed here. It achieved a more significant reduction in particle size, an increase in electronic conduction, and a higher specific energy storage capacity. [ABSTRACT FROM AUTHOR]

The aim of this review paper is to survey the fractal morphology of scale-invariant patterns. We are particularly focusing on the scale and conformal invariance, as well as on the fractal non-uniformity (multifractality), inhomogeneity (lacunarity), and anisotropy (succolarity). We argue that these features can be properly quantified by the following six adimensional numbers: the fractal (e.g., similarity, box-counting, or Assouad) dimension, conformal dimension, degree of multifractal non-uniformity, coefficient of multifractal asymmetry, index of lacunarity, and index of fractal anisotropy. The difference between morphological properties of mathematical and real-world fractals is especially outlined in this review paper. [ABSTRACT FROM AUTHOR]

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The presence of skin bacteria capable of forming biofilm, exhibiting antibiotic resistance, and displaying virulence represents a significant challenge in the field of transfusion medicine. This underscores the necessity of enhancing the microbiological safety of blood and blood components against pathogens with virulent characteristics. The aim of this work was to demonstrate bacterial inactivation in plasma by using a photoinactivation method against virulent bacteria and to evaluate coagulation factors before and after treatment. Logarithmic loads of biofilm-producing, antibiotic-resistant, and virulent bacteria isolated from skin (Enterobacter cloacae, Klebsiella ozaenae, and Staphylococcus epidermidis) were used in artificial contamination assays of fresh frozen plasma bags and subjected to photoreduction. FVIII and FI activity were evaluated before and after photoinactivation. The photoinactivation of plasma was demonstrated to be an effective method for the elimination of these bacteria. However, the efficiency of this method was found to be dependent on the bacterial load and the type of test microorganism. Conversely, decay of coagulation factors was observed with net residual activities of 61 and 69% for FVIII and FI, respectively. The photoinactivation system could have a bias in its effectiveness that is dependent on the test pathogen. These findings highlight the importance of employing technologies that increase the safety of the recipient of blood and/or blood components, especially against virulent bacteria, and show the relevance of the role of photoinactivation systems as an option in transfusion practice. [ABSTRACT FROM AUTHOR]

Copyright of Amazonia Investiga is the property of PRIMMATE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Amazonia Investiga is the property of PRIMMATE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the priority lines of action to contain the SARS-CoV-2 pandemic was vaccination programs for healthcare workers. However, with the emergence of highly contagious strains, such as the Omicron variant, it was necessary to know the serological status of health personnel to make decisions for the application of reinforcements. The aim of this work was to determine the seroprevalence against SARS-CoV-2 in healthcare workers in a Mexican hospital after six months of the administration of the Pfizer-BioNTech vaccine (two doses, 4 weeks apart) and to investigate the association between comorbidities, response to the vaccine, and reinfections. Neutralizing antibodies against SARS-CoV-2 were determined using ELISA assays for 262 employees of Hospital Juárez de México with and without a history of COVID-19. A beta regression analysis was performed to study the associated comorbidities and their relationship with the levels of antibodies against SARS-CoV-2. Finally, an epidemiological follow-up was carried out to detect reinfections in this population. A significant difference in SARS-CoV-2 seroprevalence was observed in workers with a history of COVID-19 prior to vaccination compared to those without a history of the disease (MD: 0.961 and SD: 0.049; <0.001). Beta regression showed that workers with a history of COVID-19 have greater protection compared to those without a history of the infection. Neutralizing antibodies were found to be decreased in alcoholic and diabetic subjects (80.1%). Notably, eight cases of Omicron reinfections were identified, and gender and obesity were associated with the presence of reinfections (6.41 OR; 95% BCa CI: 1.15, 105.0). The response to the vaccine was influenced by the history of SARS-CoV-2 infection and associated comorbidities. The above highlights the importance of prioritizing this segment of the population for reinforcements in periods of less than one year to guarantee their effectiveness against new variants. [ABSTRACT FROM AUTHOR]