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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.

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.

Background: As the migratory flow to the USA has intensified in recent months, health problems associated have been identified. The aim of this work was the identification of malaria cases imported into Mexican territory., Methods: Operational definitions of suspected and confirmed cases were used for investigation of malaria cases. Detection of parasitic entities by thick blood smear and molecular biology served as a confirmatory test. With the characteristics of the cases, a heat map was made to determine common clinical pictures. Finally, epidemiological analysis of cases was performed for the construction of timelines of imported malaria and the tracing of migratory routes., Results: Twelve migrants from four countries were treated for presenting clinical symptoms with suspected dengue or malaria. Malaria was confirmed and two Plasmodium species were identified. From the epidemiological dates of arrival in Mexico, onset of symptoms and migratory routes, we speculate that ten cases acquired P. vivax during their crossing through Honduras, El Salvador or Guatemala. For the Guinea cases, we conclude that there was African importation of P. falciparum., Conclusion: The epidemiological panorama of malaria cases imported into Mexico show the need to join efforts to ensure universal access to health services, with the objective of timely detection of imported cases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Periodontal Disease (PD) associated with Type 2 Diabetes Mellitus (T2DM) is a chronic condition that affects the oral cavity of people living with T2DM. The mechanisms of the interaction between type 2 Diabetes Mellitus and Periodontal diseases are complex and involve multiple pathophysiological pathways related to the systemic inflammatory process and oxidative stress. Non-surgical periodontal treatment (NSTP) is considered the standard for the management of this disease; however, patients with systemic conditions such as type 2 Diabetes Mellitus do not seem to respond adequately. For this reason, the use of complementary treatments has been suggested to support non-surgical periodontal treatment to reduce the clinical consequences of the disease and improve the systemic conditions of the patient. The use of zinc gluconate and magnesium oxide as an adjunct to non-surgical periodontal treatment and its effects on periodontal clinical features and oxidative stress in patients with Periodontal diseases -type 2 Diabetes Mellitus is poorly understood., Methods: A quasi-experimental study was performed in patients with periodontal diseases associated with T2DM. Initially, 45 subjects who met the selection criteria were included. 19 were assigned to a control group [non-surgical periodontal treatment] and 20 to the experimental group (non-surgical periodontal treatment + 500 mg of magnesium oxide and 50 mg of zinc gluconate for oral supplementation for 30 days) and the data of 6 patients were eliminated. Sociodemographic characteristics, physiological factors, biochemical parameters, and clinical features of periodontal diseases were assessed., Results: In this research a change in periodontal clinical characteristics was observed, which has been associated with disease remission. Additionally, a shift in MDA levels was presented for both groups. Furthermore, the supplementation group showed an increase in antioxidant enzymes when compared to the group that only received NSPT., Conclusion: The use of Zinc gluconate and magnesium oxide can serve as a complementary treatment to non-surgical periodontal treatment, that supports the remission of PD as a result of regulation-reduction of oxidative biomarkers and increase in antioxidant enzymes activity., Trial Registration: https://www.isrctn.com ISRCTN 14,092,381. September 13º 2023. Retrospective Registration., (© 2024. The Author(s).)

Accurately estimating population sizes for free-ranging animals through noninvasive methods, such as camera trap images, remains particularly limited by small datasets. To overcome this, we developed a flexible model for estimating upper limit populations and exemplified it by studying a group-living synanthrope, the long-tailed macaque ( Macaca fascicularis ). Habitat preference maps, based on environmental and GPS data, were generated with a maximum entropy model and combined with data obtained from camera traps, line transect distance sampling, and direct sightings to produce an expected number of individuals. The mapping between habitat preference and number of individuals was optimized through a tunable parameter ρ (inquisitiveness) that accounts for repeated observations of individuals. Benchmarking against published data highlights the high accuracy of the model. Overall, this approach combines citizen science with scientific observations and reveals the long-tailed macaque populations to be (up to 80%) smaller than expected. The model's flexibility makes it suitable for many species, providing a scalable, noninvasive tool for wildlife conservation.

Soluble secretory proteins with a signal peptide reach the extracellular space through the endoplasmic reticulum-Golgi conventional pathway. During translation, the signal peptide is recognised by the signal recognition particle and results in a co-translational translocation to the endoplasmic reticulum to continue the secretory pathway. However, soluble secretory proteins lacking a signal peptide are also abundant, and several unconventional (endoplasmic reticulum/Golgi independent) pathways have been proposed and some demonstrated. This work describes new features of the secretion signal called Nβ, originally identified in NaTrxh, a plant extracellular thioredoxin, that does not possess an orthodox signal peptide. We provide evidence that other proteins, including thioredoxins type h, with similar sequences are also signal peptide-lacking secretory proteins. To be a secretion signal, positions 5, 8 and 9 must contain neutral residues in plant proteins-a negative residue in position 8 is suggested in animal proteins-to maintain the Nβ motif negatively charged and a hydrophilic profile. Moreover, our results suggest that the NaTrxh translocation to the endoplasmic reticulum occurs as a post-translational event. Finally, the Nβ motif sequence at the N- or C-terminus could be a feature that may help to predict protein localisation, mainly in plant and animal proteins., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Zaragoza-Gómez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Class D β-lactamases OXA-232 and OXA-48 hydrolyze penicillin, cephalosporins and carbapenems, limiting the pharmacological therapeutics in bacteraemia. OXA producer microorganisms are considered a great emergent threat, especially in nosocomial environments. To determine the resistance profile and genomic characterization of two isolates initially identified as potential carbapenemase-producer Klebsiella oxytoca in a third level hospital. Automated platform BD Phoenix-100 System was used to identify and to biochemically characterize both isolates. Furthermore, the resistance profile was determined through CLSI methods and the whole genome sequences were obtained using Next-Generation Sequencing. Resistance genes were analyzed, and the virtual fingerprinting was determined to corroborate the similarity with related bacteria. Both strains correspond to Raoultella ornithinolytica carrying OXA 232 and OXA-48 genes, confirming the class D β-lactamases assay results. Here, we present the genetic and phenotypic analysis of multidrug resistance R. ornithinolytica, representing the first report in Mexico., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives. To examine homicide rates in Cali, Colombia, during the 1993-2018 period, using information derived from an interagency surveillance system. Methods. We used homicide data from Cali's Epidemiological Surveillance System to examine homicide trends by victim's age and sex, time, and type of method used. We estimated trend changes and the annual percentage changes using joinpoint regression analyses. Results. Homicide rates per 100 000 inhabitants dropped from 102 in 1993 to 47.8 in 2018. We observed reductions in homicide rates across age and sex groups. Most homicide victims were men aged 20 to 39 years from poor, marginalized areas. Firearms were used in 84.9% of all cases. The average annual percentage change for the entire period was -3.6 (95% confidence interval = -6.7, -0.4). Conclusions. Fluctuations in homicide rates in Cali show a clear epidemic pattern, occurring concurrently with the "crack epidemic" in different countries. Reliable and timely information provided by an Epidemiological Surveillance System allowed opportune formulation of public policies to reduce the impact of violence in Cali.

Introduction: Infections acquired in hospitals are the cause of high morbidity and mortality and with the emergence of resistant bacteria, the problem is greater. The aim of this work was to determine the genetic characteristics and timeline of Klebsiella pneumoniae blaNDM-1 carrying a class 1 integron involved in an intrahospital outbreak., Methodology: Investigation was made from the first detection of K. pneumoniae blaNDM-1, strain "466", and the last clone "423". 16S rRNA gene analysis showed that 466 strain and clones were related to K. pneumoniae. Extended-spectrum β-lactamases (ESBL) was detected according to the Clinical and Laboratory Standards Institute (CLSI) and real time-PCR. Typing of K. pneumoniae blaNDM-1 strains was carried by ERIC-PCR and sequencing the variable region of the integrons were performed., Results: A cluster of six resistant isolates of K. pneumoniae blaNDM-1 was detected in intensive care unit (ICU), internal medicine (IM) and orthopedics (OT). Timeline revealed that the first bacterial identification was in ICU and the last clone in OT service. The array genetic of variable region was "IntI/aadA5-drfA17/qacEΔ1-Sul1"., Conclusions: The evidences highlight the importance of the epidemiological surveillance of Extended-spectrum β-lactamases (ESBL) strains, as well as the need for molecular epidemiological studies to identify the routes of transmission and the contamination sources within health personnel., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2021 Iliana Alejandra Cortes-Ortiz, Julio Cesar Juarez-Gomez, Concepcion Cu-Quijano, Rocio Flores-Paz, Emilio Mariano Duran-Manuel, Clemente Cruz-Cruz, Victor Hugo Gutierrez-Munoz, Oscar Sosa-Hernandez, Noe Escobar-Escamilla, Juan Carlos Bravata-Alcantara, Laura Delgado-Balbuena, Gabriela Ibanez-Cervantes, Juan Manuel Bello-Lopez.)

Objective: Describe the results of the Program for the Rational Use of Antimicrobials at Mexico's Juárez Hospital., Methods: An observational, cross-sectional, retrospective, descriptive study was designed. For the consumption of antimicrobial agents, data from January 2013 to December 2018 were analyzed by calculating the defined daily dose (DDD). For the cost analysis, a traditional costing calculation was used., Results: For the group of carbapenem agents, there was a sizeable reduction in the consumption of imipenem / cilastatin: the DDD declined from 2.3 in 2013 to 0.7 in 2018, a decrease of 70%. By contrast, for the other two agents, increases were observed. The consumption of meropenem increased by 2% (from 2.4 in 2013 to 2.5 in 2018); the consumption of ertapenem increased by 75% (from 1 in 2013 to 1.8 in 2018). The total expenditure on antimicrobial agents was USD 930 556.46 during 2013, compared to USD 856 079.10 during 2018, representing a difference of 8% or USD 74 905.61 of the total expenditure., Conclusions: Programs for the rational use of antimicrobials need to be evaluated continuously, by monitoring both consumption of agents by patients and related institutional expenditures.

Argument This paper analyzes the research strategies of three different cases in the study of human genetics in Mexico - the work of Rubén Lisker in the 1960s, INMEGEN's mapping of Mexican genomic diversity between 2004 and 2009, and the analysis of Native American variation by Andrés Moreno and his colleagues in contemporary research. We make a distinction between an approach that incorporates multiple disciplinary resources into sampling design and interpretation (unpacking), from one that privileges pragmatic considerations over more robust multidisciplinary analysis (flattening). These choices have consequences for social, demographic, and biomedical practices, and also for accounts of genetic variation in human populations. While the former strategy unpacks fine-grained genetic variation - favoring precision and realism, the latter tends to flatten individual differences and historical depth in lieu of generalization.

In this research a novel interferometric system is reported, which allows the generation of four simultaneous interferograms with phase shifts of π/2. The system consists of three coupled interferometers: a rectangular Sagnac interferometer which generates a primary pattern with crossed circular polarizations, coupled to two Michelson interferometers which operate as a multiplexing system, and generating replicas of the primary pattern. The two coupled Michelson interferometers generate four patterns retaining their polarization properties, which allow independent phase shifts by placing a linear polarizer over each pattern, thereby, four interferograms with relative phase shifts of π/2 are obtained. The optical phase is calculated using the well-known four-step algorithm. With knowledge of the optical phase, different properties of the samples can be calculated or analyzed; in this case, by knowing the mean refractive index, we can calculate the mean thickness of test objects. The results obtained for static transparent samples are presented. The capability of the system to analyze dynamic events is shown when results for the calculation of a temperature field of a heat flow are presented.

For applications involving time varying optical phase distributions, fast cameras and/or pulsed lasers have to be used. To apply phase-shifting interferometry techniques (PSI) as well, single shot capture is required. Among others, modulation of polarization and phase grating interferometry is a possible technique to be considered. In this paper, a report about the use of this technique based on a double pulse laser system is presented. Single-pulse and twin-pulse operations are considered both in optical interferometers as well as in ESPI systems (mainly in subtraction mode). In ESPI a reduction of the degree of polarization appears due to scattering, so some measures have to be taken to prevent such deletereous effect. To show the feasibility of the proposed variants some experimental results are presented.

We present a technique which allows us to generate two parallel interferograms with phase shifts of π/2 using a Cyclic Shear Interferometer (CSI) and a polarizing splitter. Because of the use of a CSI, we obtain the derivative phase data map directly, due to its configuration, it is immune to vibrations because the reference wavefront and the object wavefront have a common path; the shearing interferometer is insensitive to temperature and vibration. To obtain the optical phase data map, two interferograms are generated by collocating a polarizing device at the output of the CSI. The optical phase was processed using a Vargas-Quiroga algorithm. Related experimental results obtained for dynamic microscopic transparent samples are presented.

Despite the promises made by molecular evolutionists since the early 1960s that phylogenies would be readily reconstructed using molecular data, the construction of molecular phylogenies has both retained many methodological problems of the past and brought up new ones of considerable epistemic relevance. The field is driven not only by changes in knowledge about the processes of molecular evolution, but also by an ever-present methodological anxiety manifested in the constant search for an increased objectivity-or in its converse, the avoidance of subjectivity. This paper offers an exhaustive account of the methodological and conceptual difficulties embedded in each of the steps required to elaborate molecular phytogenies. The authors adopt a historical perspective on the field in order to follow the development of practices that seek to increase the objectivity of their methods and representations. These include the adoption and development of explicit criteria for evaluation of evidence, and of procedures associated with methods of statistical inference, quantification and automation. All these are linked to an increasing use of computers in research since the mid 1960s. We will show that the practices of objectivity described are highly dependent on the problems and tools of molecular phylogenetics.

Aims: A parametric study was conducted to define optimum conditions to achieve high yields in the conversion of tyrosine to eumelanin (EuMel) using recombinant Escherichia coli., Methods and Results: Escherichia coli W3110 (pTrcMutmelA) expressing the tyrosinase coding gene from Rhizobium etli and glucose-mineral media were used to transform tyrosine into EuMel. Batch aerobic fermentor cultures were performed to study the effect of temperature, pH and inducer concentration (isopropyl-D-thio-galactopyranoside) on melanin production. Under optimum conditions, 0.1 mmol l(-1) of isopropyl-D-thio-galactopyranoside, temperature of 30 degrees C, and changing pH from 7.0 to 7.5 during the production phase, a 100% conversion of tyrosine into EuMel is obtained. Furthermore, tyrosine feeding allowed us to obtain the highest level (6 g l(-1)) of EuMel produced by recombinant E. coli reported until now., Conclusions: The most important factors affecting melanin formation and hence influencing the rate and efficiency in the conversion of tyrosine into EuMel in this system, are the temperature and pH., Significance and Impact of the Study: Maximum theoretical yield was obtained using a simple culture process and mineral media to convert tyrosine (a medium value compound) into melanin, a high value compound. The process reported here avoids the use of purified tyrosinase, expensive chemical methods or the cumbersome extraction of this polymer from animal or plant tissues.