Metformin, a biological and synthetic overview.

Metformin is the most widely known anti-hyperglycemic, officially acquired by the USA government in 1995 and in 2001 it became the most prescribed treatment for type II diabetes. But how did it become the must-use drug for this disease in such a short period of time? it all started with traditional medicine, by using a plant known as "goat's rue" for the reduction of blood glucose levels. Its use arose in 1918 and evolved to the metformin synthesis in laboratories a couple of years later, using very rudimentary methods which involved melting and strong heating. Thus, a first synthetic route that allowed the preparation of the initial metformin derivates was established. Some of these resulted toxics, and others outperformed the metformin, reducing the blood glucose levels in such efficient way. Nevertheless, the risk and documented cases of lactic acidosis increased with metformin derivatives like buformin and phenformin. Recently, metformin has been widely studied, and it has been associated and tested in the treatment of type II diabetes, cancer, polycystic ovarian syndrome, cell differentiation to oligodendrocytes, reduction of oxidative stress in cells, weight reduction, as anti-inflammatory and even in the recent COVID-19 disease. Herein we briefly review and analyze the history, synthesis, and biological applications of metformin and its derivates.

A new epigean harvestman of the genus Guerrobunus (Laniatores: Phalangodidae), from Hidalgo, Mexico, with taxonomic notes about the genus.

The fifth species of the genus Guerrobunus, Guerrobunus barralesi sp. nov. is described from specimens collected in Hidalgo, Mexico. This species represents the first eastern record from the country and unlike other species of the genus, is completely epigean. Guerrobunus barralesi sp. nov. is compared with the most similar species, Guerrobunus minutus, which also has well developed and pigmented eyes. Finally, external morphology, including male genitalia, taxonomy of the genus, and familial assignment into the family Phalangodidae are discussed.

Use of Medicinal Plants in the Process of Wound Healing: A Literature Review.

The literature on the use of medicinal plants in wound healing was comprehensively searched to obtain and assess the data. The data were procured via clinical studies that utilized medicinal plants and their compounds in vitro and in vivo for wound healing. This review collected data from electronic databases, including Google Scholar, PubMed, Science Direct, Web of Science, SciFinder, Thesis, and Scopus, using the search terms "natural products", "wound healing", and "natural compounds", along with the keywords "plants", "extracts", and "phytochemicals". Results from the last decade reveal a total of 62 families and 109 genera of medicinal plants, and their compounds have been studied experimentally both in vivo and in vitro and clinically found to effectively promote healing. This activity is related to the presence of secondary metabolites such as flavonoids, alkaloids, saponins, tannins, terpenoids, and phenolic compounds, which act at different stages through different mechanisms to exert anti-inflammatory, antimicrobial, and antioxidant effects, confirming that the use of medicinal plants could be an adequate alternative to current conventional practices for treating wounds.

Imaging of 3 bright terrestrial gamma-ray flashes by the atmosphere-space interactions monitor and their parent thunderstorms.

The Atmosphere-Space Interactions Monitor (ASIM) on the International Space Station (ISS) includes an instrument designed to geolocate Terrestrial Gamma-ray Flashes (TGF) produced by thunderstorms. It does so with a coded aperture system shadowing the pixelated Low Energy Detector of the Modular X- and Gamma-ray Sensor (MXGS). Additionally, it locates associated lightning flashes with the Modular Multispectral Imaging Array (MMIA). Here we present 3 bright TGFs with very similar duration, fluency and observation distance. The innovative imaging capabilities allow us to determine the TGF position and correlate the TGF-lightning parent event in time and position simultaneously. The accurate position determination and distance to the observer allow us to perform a comparative study of TGF characteristics. These TGFs were produced in association with lightning flashes below the highest cloud tops of developing to mature convective cells. In one event, GLM (Geostationary Lightning Mapper) cloud flash rates were slowing down after the TGF while negative cloud-to-ground flashes suddenly ceased from 10 to 5 min before the TGF. An 8-stroke (strongest: -93 kA) cloud-to-ground flash occurred 31 s before the TGF. Vertical profiles from the ERA5 reanalysis data suggest TGFs may be produced in variety of tropical environments.

Farmed stage (age)-dependent accumulation and size of microplastics in Litopenaeus vannamei shrimp reared in a super-intensive controlled system.

The abundance of microplastics (MPs) in the gastrointestinal tract (GT), gills (GI), and exoskeleton (EX) of Litopenaeus vannamei shrimp cultured in a commercial indoor super-intensive controlled (ISCO) system was investigated. Shrimp of 25 days (postlarvae; PL25), and one, three, five, and seven culture months were analyzed. The postlarvae PL25 MP abundance per individual and gram of PL (wet weight) was 0.2 ± 0.0 MPs and 3.5 ± 0.5 MPs/g. For L. vannamei juveniles at one, three, five, and seven culture months, the MP abundance per juvenile shrimp was 10.0 ± 0.3, 27.2 ± 1.6, 32.3 ± 3.1, and 40.3 ± 3.6 MPs/individual, respectively (expressed in MPs/g of tissue were 1.6 ± 0.1, 2.0 ± 0.2, 2.0 ± 0.3 and 1.5 ± 0.2, respectively). Fibers were the most common MP type in all shrimp age classes (42.1-68.7 %), and the predominant color was transparent (46.1-65.0 %). The MP size in all shrimp stages ranged between 15 and 4686 µm. In general, the predominant polymers identified were PE (37.4 %), NY (21.1 %), and PET (18.5 %). The MP variability through the culture cycle showed that as the age of shrimp increased, and the culture advanced the MP abundance and size also augmented. Conversely, there is a higher MP abundance in L. vannamei cultured in ISCO systems compared to shrimp cultured in traditional semi-intensive and intensive ponds and those from wild environments. The latter is probably due to the extensive use of plasticized materials (geomembrane and greenhouse installations) and their degradation, which cause a greater MP exposure to shrimp. The estimated oral MP intake by ISCO shrimp consumption was 647 MPs/capita/year, which can be 178 % more than from wild shrimp.

An intelligent surveillance platform for large metropolitan areas with dense sensor deployment.

This paper presents an intelligent surveillance platform based on the usage of large numbers of inexpensive sensors designed and developed inside the European Eureka Celtic project HuSIMS. With the aim of maximizing the number of deployable units while keeping monetary and resource/bandwidth costs at a minimum, the surveillance platform is based on the usage of inexpensive visual sensors which apply efficient motion detection and tracking algorithms to transform the video signal in a set of motion parameters. In order to automate the analysis of the myriad of data streams generated by the visual sensors, the platform's control center includes an alarm detection engine which comprises three components applying three different Artificial Intelligence strategies in parallel. These strategies are generic, domain-independent approaches which are able to operate in several domains (traffic surveillance, vandalism prevention, perimeter security, etc.). The architecture is completed with a versatile communication network which facilitates data collection from the visual sensors and alarm and video stream distribution towards the emergency teams. The resulting surveillance system is extremely suitable for its deployment in metropolitan areas, smart cities, and large facilities, mainly because cheap visual sensors and autonomous alarm detection facilitate dense sensor network deployments for wide and detailed coverage.

Two new species of the genus Paramitraceras Pickard-Cambridge, 1905 (Opiliones: Laniatores: Stygnopsidae) from Chiapas, Mexico.

Parainitraceras pickardcanibridgei sp. nov. and Paramitraceras tzotzil sp. nov. from Chiapas, Mexico are described based on specimens previously determined as Paramitraceras granulatum Pickard-Cambridge, 1905 by Goodnight and Goodnight. The male genitalia of the new species and P. granulatum are illustrated with scanning electronic micrographs (SEMs) or drawings derived from them. The importance of the ocular tubercle, cheliceral dentition and sexual dimorphism, pedipalpal armature and male genitalia as taxonomic characters within the genus is discussed as well as differences and similarities between Paramitraceras Pickard-Cambridge, 1905 and its most similar genus, Sbordonia Silhavý, 1977.

Spontaneous pneumopericardium and pneumomediastinum as atypical complication for SARS-CoV-2.

SARS-CoV-2 (COVID-19) disease is an infection caused by a new emerging coronavirus, the most common clinical manifestations include fever, dry cough, dyspnea, chest pain, fatigue, and myalgia, sometimes it may present with atypical manifestations such as spontaneous pneumothorax and pneumomediastinum that occur in a minority of patients. We report a case of spontaneous pneumopericardium in a 60-year-old male, without comorbidities or a history of trauma, with pneumonia due to SARS-CoV-2.

La enfermedad por SARS-CoV-2 (COVID-19) es una infección causada por un nuevo coronavirus emergente. Las manifestaciones clínicas más comunes incluyen fiebre, tos seca, disnea, dolor de pecho, fatiga y mialgias. En ocasiones puede presentarse con manifestaciones atípicas, como neumotórax espontáneo y neumomediastino, que ocurren en una minoría de pacientes. Reportamos un caso de neumopericardio espontáneo en un varón de 60 años, sin comorbilidad ni antecedente de traumatismo, con neumonía por SARS-CoV-2.

A long-term dataset of sable isotopes in rainfall at the North American monsoon region in southern Sonora, Mexico.

The objective of this work is to present a long-term dataset of water stable isotopes in rainfall samples from northwestern Mexico. These data is useful to generate a local meteoric water line as a reference tool for atmospheric and ecohydrological studies within the North American Monsoon region and to compare across the globe. This work shows the isotopic variation of the rainfall collected at a permanent location in Ciudad Obregon, Sonora, Mexico (27.511850, -109.956316), between 2014 and 2021. The isotopic composition of 138 rain samples was analyzed for both oxygen (δ18O) and deuterium (δ2H) with laser spectroscopy. The slope of the resulting local meteoric water line was m = 6.59 with an intercept of -1.15 (R² = 0. 91). During the monitored period at the studied region the presence of hurricanes, cold fronts and the hegemony of rainfall attributed to the North American Monsoon is recorded in the dataset.

Anatomy of digital contact tracing: Role of age, transmission setting, adoption, and case detection.

The efficacy of digital contact tracing against coronavirus disease 2019 (COVID-19) epidemic is debated: Smartphone penetration is limited in many countries, with low coverage among the elderly, the most vulnerable to COVID-19. We developed an agent-based model to precise the impact of digital contact tracing and household isolation on COVID-19 transmission. The model, calibrated on French population, integrates demographic, contact and epidemiological information to describe exposure and transmission of COVID-19. We explored realistic levels of case detection, app adoption, population immunity, and transmissibility. Assuming a reproductive ratio R = 2.6 and 50% detection of clinical cases, a ~20% app adoption reduces peak incidence by ~35%. With R = 1.7, >30% app adoption lowers the epidemic to manageable levels. Higher coverage among adults, playing a central role in COVID-19 transmission, yields an indirect benefit for the elderly. These results may inform the inclusion of digital contact tracing within a COVID-19 response plan.

Effect of pH, aeration and feeding non-sterilized agave juice in a continuous agave juice fermentation.

BACKGROUND: Continuous cultures have been used since the 1950s in beer and wine fermentations due to their higher productivities compared to traditional batch systems; nevertheless, the tequila industry has not taken advantage of the possible improvements that continuous fermentations could offer. In this work, the effect of pH, aeration and feeding of non-sterilized medium, on the fermentative capability of two Saccharomyces cerevisiae strains (S1 and S2) cultured in continuous fermentation, using agave juice as the fermentation medium, were studied. RESULTS: In continuous cultures, the control of the medium pH (set point at 4) did not have a significant effect on fermentation efficiency compared to fermentations in which the pH was not controlled (pH 2.5 +/- 0.3). Conversely, aeration of the cultures of both strains improved biomass production and consumption of reducing sugars and ammonium. The aeration also significantly augmented ethanol production only for S1 cultures (P < 0.05). Furthermore, the feeding of medium, either sterilized or not, did not show significant differences on the production of ethanol for S1 cultures. Higher concentrations of acetoin, succinic acid and diacetyl were found in the cultures fed with non-sterilized medium. CONCLUSIONS: Compared to S2, S1 has a better fermentative performance in continuous non-sterilized medium fermentations. Not controlling the pH during the cultures could prevent the possibility of microbial contamination as a result of the extreme medium acidity (pH 2.5 +/- 0.3). This work showed the possibility of scaling up agave juice continuous fermentation feeding non-sterilized medium with no control of pH.

Two new genera of epigean harvestmen (Opiliones, Stygnopsidae) from Oaxaca, Mexico, with an identification key for the stygnopsine genera.

Two new genera, Ampliphallus gen. nov. and Guelaguetzia gen. nov., are described from material collected in the state of Oaxaca, Mexico. The genus Ampliphallus gen. nov. is monotypic and contains the species A. chimalapaensis sp. nov., from the tropical rain forest of Santa María Chimalapa, Oaxaca. The genus Guelaguetzia gen. nov. is composed of two species: G. cuicateca sp. nov. (type species) and G. serrana sp. nov., from pine forests in northern Oaxaca. These genera can be recognized from each other mainly by the armature of leg IV and by the male genitalia; both are also compared with the remaining members of the Stygnopsinae. An identification key for all genera of the subfamily is provided.

Gigantic jet discharges evolve stepwise through the middle atmosphere.

In 2002 it was discovered that a lightning discharge can rise out of the top of tropical thunderstorms and branch out spectacularly to the base of the ionosphere at 90 km altitude. Several dozens of such gigantic jets have been recorded or photographed since, but eluded capture by high-speed video cameras. Here we report on 4 gigantic jets recorded in Colombia at a temporal resolution of 200 µs to 1 ms. During the rising stage, one or more luminous steps are revealed at 32-40 km, before a continuous final jump of negative streamers to the ionosphere, starting in a bidirectional (bipolar) fashion. The subsequent trailing jet extends upward from the jump onset, with a current density well below that of lightning leaders. Magnetic field signals tracking the charge transfer and optical Geostationary Lightning Mapper data are now matched unambiguously to the precisely timed final jump process in a gigantic jet.

A new leaf-litter harvestman species of the genus Karos (Opiliones: Stygnopsidae: Karosinae), with a reanalysis of the morphological phylogeny of the genus.

Karos Goodnight Goodnight, 1944 is the most diverse genus of the family Stygnopsidae. It contains seven micro-endemic species from the Huasteca region in eastern Mexico. In this paper, the new species Karos morronei sp. nov. is described based on the morphology of adults of both sexes. The new species is from Zacualtipán de Ángeles, Hidalgo State, which represents the southernmost record for the genus. Additionally, a reanalysis of the previous morphological phylogeny of the genus using both parsimony and maximum likelihood methods is provided. According to the morphological reanalysis, K. morronei sp. nov. exhibits an autapomorphy (males with femur IV thicker than females) and is the sister group of the clade that includes K. barbarikos, K. hexasetosus, K. monjarazi, K. parvus and K. singularis. Finally, information of barcoding (CO1) is provided for this new species.

Metabolomics applied to the discovery of tuberculosis and diabetes mellitus biomarkers.

Tuberculosis (TB) and diabetes mellitus Type 2 (DM2) are two diseases as ancient as they are harmful to human health. The outcome for both diseases in part depends on immune and metabolic individual responses. DM2 is increasing yearly, mainly due to environmental, genetic and lifestyle habits. There are multiple evidence that DM2 is one of the most important risk factor of becoming infected with TB or reactivating latent TB. Mass spectrometry-based metabolomics is an important tool for elucidating the metabolites and metabolic pathways that influence the immune responses to M. tuberculosis infection during diabetes. We provide an up-to-date review highlighting the importance and benefit of metabolomics for identifying biomarkers as candidate molecules for diagnosis, disease activity or prognosis.

[Aneurisma de arteria testicular: reporte de un caso y revisión de la literatura]. / Testicular artery aneurysm: case report and review of the literature.

Background: Aneurysm of the testicular artery is a rare entity; the term is described as the dilation of any blood vessel in the body. Case report: An 18-year-old patient with a left testicular artery aneurysm, with no family or personal history of medical importance, presented for consultation due to a volume increase of long evolution in the inguinal region, accompanied by sporadic pain with no other symptoms. The testicular artery aneurysm was not detectable preoperatively by ultrasound, which only reported data compatible with left inguinal hernia and varicocele. The diagnosis was made postoperatively by a histopathological study. This case highlights the presentation of a true aneurysm of the testicular artery and the result after definitive surgical treatment. Conclusions: The etiology of the aneurysm and pseudoaneurysm reported in the literature is described after a testicular trauma and, a few cases of congenital origin. The clinical manifestations are pain and an inguinal mass, which can be frequently confused with inguinal hernias or an aggregated pathology. Therefore, the approach of patients with inguinal or testicular pathology should be protocolized and include aneurysm within the differential diagnoses.

Introducción: El aneurisma de la arteria testicular es poco frecuente; el término se describe como la dilatación de cualquier vaso sanguíneo en el cuerpo. Caso clínico: Se presenta el caso de un paciente de 15 años con un aneurisma de la arteria testicular izquierda sin ningún antecedente de importancia familiar ni personal, quien se presentó a consulta por aumento de volumen en la región inguinal de larga evolución, acompañado de dolor esporádico y sin más síntomas. Se diagnosticó hernia inguinal y se procedió a cirugía. El diagnóstico se realizó de manera posoperatoria por medio de estudio histopatológico. En este caso, se destaca la presentación de un aneurisma verdadero de la arteria testicular y el resultado después del tratamiento quirúrgico definitivo. Conclusiones: La etiología del aneurisma y del pseudoaneurisma reportada en la literatura se describe posterior a un traumatismo testicular, y en pocos casos de origen congénito. Las manifestaciones clínicas pueden ser dolor y una masa inguinal, y muchas de las veces pueden confundirse con hernias inguinales o ser una patología agregada, por lo que el abordaje de los pacientes con patología inguinal o testicular debe ser protocolizado e incluir el aneurisma dentro de los diagnósticos diferenciales.

A second species of the genus Martensolasma (Opiliones, Dyspnoi, Nemastomatidae) from Mexico.

A second species of the previously monotypic genus Martensolasma Shear, 2006 is described: Martensolasma catrina sp. n., based on specimens collected in Metztitlán, Hidalgo, Mexico. The taxonomy the genus is briefly discussed.

Prediction models in the design of neural network based ECG classifiers: a neural network and genetic programming approach.

BACKGROUND: Classification of the electrocardiogram using Neural Networks has become a widely used method in recent years. The efficiency of these classifiers depends upon a number of factors including network training. Unfortunately, there is a shortage of evidence available to enable specific design choices to be made and as a consequence, many designs are made on the basis of trial and error. In this study we develop prediction models to indicate the point at which training should stop for Neural Network based Electrocardiogram classifiers in order to ensure maximum generalisation. METHODS: Two prediction models have been presented; one based on Neural Networks and the other on Genetic Programming. The inputs to the models were 5 variable training parameters and the output indicated the point at which training should stop. Training and testing of the models was based on the results from 44 previously developed bi-group Neural Network classifiers, discriminating between Anterior Myocardial Infarction and normal patients. RESULTS: Our results show that both approaches provide close fits to the training data; p = 0.627 and p = 0.304 for the Neural Network and Genetic Programming methods respectively. For unseen data, the Neural Network exhibited no significant differences between actual and predicted outputs (p = 0.306) while the Genetic Programming method showed a marginally significant difference (p = 0.047). CONCLUSIONS: The approaches provide reverse engineering solutions to the development of Neural Network based Electrocardiogram classifiers. That is given the network design and architecture, an indication can be given as to when training should stop to obtain maximum network generalisation.

Aneurisma de arteria testicular: reporte de un caso y revisión de la literatura / Testicular artery aneurysm: case report and review of the literature

Resumen: Introducción: El aneurisma de la arteria testicular es poco frecuente; el término se describe como la dilatación de cualquier vaso sanguíneo en el cuerpo. Caso clínico: Se presenta el caso de un paciente de 15 años con un aneurisma de la arteria testicular izquierda sin ningún antecedente de importancia familiar ni personal, quien se presentó a consulta por aumento de volumen en la región inguinal de larga evolución, acompañado de dolor esporádico y sin más síntomas. Se diagnosticó hernia inguinal y se procedió a cirugía. El diagnóstico se realizó de manera posoperatoria por medio de estudio histopatológico. En este caso, se destaca la presentación de un aneurisma verdadero de la arteria testicular y el resultado después del tratamiento quirúrgico definitivo. Conclusiones: La etiología del aneurisma y del pseudoaneurisma reportada en la literatura se describe posterior a un traumatismo testicular, y en pocos casos de origen congénito. Las manifestaciones clínicas pueden ser dolor y una masa inguinal, y muchas de las veces pueden confundirse con hernias inguinales o ser una patología agregada, por lo que el abordaje de los pacientes con patología inguinal o testicular debe ser protocolizado e incluir el aneurisma dentro de los diagnósticos diferenciales.

Abstract: Background: Aneurysm of the testicular artery is a rare entity; the term is described as the dilation of any blood vessel in the body. Case report: An 18-year-old patient with a left testicular artery aneurysm, with no family or personal history of medical importance, presented for consultation due to a volume increase of long evolution in the inguinal region, accompanied by sporadic pain with no other symptoms. The testicular artery aneurysm was not detectable preoperatively by ultrasound, which only reported data compatible with left inguinal hernia and varicocele. The diagnosis was made postoperatively by a histopathological study. This case highlights the presentation of a true aneurysm of the testicular artery and the result after definitive surgical treatment. Conclusions: The etiology of the aneurysm and pseudoaneurysm reported in the literature is described after a testicular trauma and, a few cases of congenital origin. The clinical manifestations are pain and an inguinal mass, which can be frequently confused with inguinal hernias or an aggregated pathology. Therefore, the approach of patients with inguinal or testicular pathology should be protocolized and include aneurysm within the differential diagnoses.