Immunity and COVID-19 vaccines. Revisiting the bases.

The COVID-19 pandemic is one of the challenges of the 21st century; science and technology were put to the test for the development vaccines, diagnostic techniques and treatments in record time. However, misinformation and misinterpretation have made the safety and efficacy of COVID-19 vaccines a subject of debate. This review addresses concepts on immunization mechanisms and vaccination, as well as evidence supporting that COVID-19 vaccines are immunogenic, efficacious and safe.

La pandemia de COVID-19 es uno de los retos del siglo XXI; la ciencia y la tecnología se pusieron a prueba para desarrollar vacunas, técnicas diagnósticas y tratamientos en tiempo récord. No obstante, la desinformación y mala interpretación han hecho que la seguridad y eficacia de las vacunas contra COVID-19 sean un tema de debate. En esta revisión se abordan conceptos sobre los mecanismos de la inmunización y la vacunación; así como la evidencia que sostiene que las vacunas contra COVID-19 son inmunogénicas, eficaces y seguras.

Inmunidad y vacunas contra la COVID-19. Revisando las bases / Immunity and COVID-19 vaccines. Revisiting the bases

Resumen La pandemia de COVID-19 es uno de los retos del siglo XXI; la ciencia y la tecnología se pusieron a prueba para desarrollar vacunas, técnicas diagnósticas y tratamientos en tiempo récord. No obstante, la desinformación y mala interpretación han hecho que la seguridad y eficacia de las vacunas contra COVID-19 sean un tema de debate. En esta revisión se abordan conceptos sobre los mecanismos de la inmunización y la vacunación; así como la evidencia que sostiene que las vacunas contra COVID-19 son inmunogénicas, eficaces y seguras.

Abstract The COVID-19 pandemic is one of the challenges of the 21st century; science and technology were put to the test for the development vaccines, diagnostic techniques and treatments in record time. However, misinformation and misinterpretation have made the safety and efficacy of COVID-19 vaccines a subject of debate. This review addresses concepts on immunization mechanisms and vaccination, as well as evidence supporting that COVID-19 vaccines are immunogenic, efficacious and safe.

RET gene mutational diagnosis and precision medicine in Mexico.

Precision medicine is a reality in some diseases; it supports the development of accurate and specific diagnostic methods, new drugs and molecules. Our research team in Mexico, made up of clinical and biomedical researchers, has been performing free RET gene mutational diagnosis for medullary thyroid cancer and multiple endocrine neoplasia (MEN) 2 and 3 for 20 years. RET pathogenic variants in the Mexican population are consistent with reported data: most common mutations are 634/NEM2 and 918/NEM3. Currently, new nanobiotechnology methods are being developed for this type of determination in order to obtain faster, simpler, more sensitive and specific results applicable in all types of laboratories.

La medicina de precisión en algunas enfermedades es una realidad; respalda el desarrollo de métodos diagnósticos certeros y específicos, de nuevas drogas y moléculas. Nuestro equipo de investigación en México, conformado por investigadores clínicos y biomédicos, desde hace 20 años realiza de forma gratuita el diagnóstico mutacional del gen RET y su relación con el cáncer medular de tiroides y la neoplasia endocrina múltiple (NEM) 2 y 3. Las variantes patogénicas de RET en la población mexicana coinciden con los datos reportados: la mayoría con 634/NEM2 y 918/NEM3. Actualmente se están desarrollando nuevos métodos de nanobiotecnología para este tipo de determinaciones, de tal forma que puedan obtenerse resultados más rápidos, simples, sensibles y específicos aplicables en todo tipo de laboratorio.

Diagnóstico mutacional del gen RET y la medicina de precisión en México / RET gene mutational diagnosis and precision medicine in Mexico

Resumen La medicina de precisión en algunas enfermedades es una realidad; respalda el desarrollo de métodos diagnósticos certeros y específicos, de nuevas drogas y moléculas. Nuestro equipo de investigación en México, conformado por investigadores clínicos y biomédicos, desde hace 20 años realiza de forma gratuita el diagnóstico mutacional del gen RET y su relación con el cáncer medular de tiroides y la neoplasia endocrina múltiple (NEM) 2 y 3. Las variantes patogénicas de RET en la población mexicana coinciden con los datos reportados: la mayoría con 634/NEM2 y 918/NEM3. Actualmente se están desarrollando nuevos métodos de nanobiotecnología para este tipo de determinaciones, de tal forma que puedan obtenerse resultados más rápidos, simples, sensibles y específicos aplicables en todo tipo de laboratorio.

Abstract Precision medicine is a reality in some diseases; it supports the development of accurate and specific diagnostic methods, new drugs and molecules. Our research team in Mexico, made up of clinical and biomedical researchers, has been performing free RET gene mutational diagnosis for medullary thyroid cancer and multiple endocrine neoplasia (MEN) 2 and 3 for 20 years. RET pathogenic variants in the Mexican population are consistent with reported data: most common mutations are 634/NEM2 and 918/NEM3. Currently, new nanobiotechnology methods are being developed for this type of determination in order to obtain faster, simpler, more sensitive and specific results applicable in all types of laboratories.

Intraparenchymal Brain Abscess in an Adult Male With Underlying Ebstein Anomaly and Cor Triatriatum Dexter.

A 21-year-old man presented with new-onset seizures and brain abscess. Echocardiography and cardiac magnetic resonance imaging revealed underlying Ebstein anomaly, secundum atrial septal defect, and cor triatriatum dexter. The elevated right heart pressures shunting through the septal defect and transient bacteremia were the likely mechanisms for his presentation. (Level of Difficulty: Intermediate.).

Chronic stress decreases ornithine decarboxylase expression and protects against 1,2-dimethylhydrazine-induced colon carcinogenesis.

Biological response to stress depends on the type, timing, and severity of the stressor. Acute stressful environments may positively activate molecular and cellular mechanisms to favor adaptation; however, chronic stress is often associated with detrimental health effects. Colon cancer (CC) is one of the leading causes of death associated with cancer and has been mentioned as a stress-related disease. In the present work, the effect of chronic stress on the initial phase of CC was evaluated, and special emphasis was placed on ornithine decarboxylase (ODC) expression and polyamines for their role in hyperproliferative diseases. BALB/c mice (n = 5/group) were administered the pro-carcinogen 1,2-dimethylhydrazine (DMH) for 8 weeks (20 mg/kg body weight/week) to induce colon carcinogenesis, and then exposed for 4 weeks to two physical stressors: restraint and forced-swimming. Distal colon inflammatory lesions and histomorphological changes were evaluated by hematoxylin-eosin staining; plasma corticosterone levels, colon ODC expression, and urinary polyamines were determined by competitive ELISA, RT-qPCR, Western Blot, and HPLC, respectively. The short-term exposure to DMH triggered colon inflammation, initiated colon carcinogenesis and increased ODC expression; meanwhile, the exposure to chronic stress activated the hypothalamic-pituitary-adrenal (HPA) axis, elicited the production of plasmatic corticosterone, and decreased ODC expression. The exposure of DMH-treated mice to chronic stress counteracted the inflammatory effect of DMH and maintained ODC homeostasis. In early phase of carcinogenesis, the exposure of DMH-treated mice to chronic stress had a positive effect against colon inflammation and maintained ODC homeostasis. The cross-talk between corticosterone, ODC expression, and inflammation in a tumor environment is discussed.

Dual-hemispheric transcranial direct current stimulation (tDCS) over primary motor cortex does not affect movement selection.

Volition and sense of agency are two primary components of a voluntary or internally generated movement. It has been shown that movement selection cannot be altered without interfering with the sense of volition using single pulse transcranial magnetic stimulation over the primary motor cortex. In the current study, we aimed at examining whether modulating the cortical excitability of the final effector in the voluntary motor pathway-the primary motor cortex, using transcranial direct current stimulation (tDCS) would alter movement selection. Our hypothesis was that anodal tDCS would increase motor cortical excitability and thereby decrease the threshold for movement execution, which could favor selection of the contralateral hand. We recruited 13 healthy adults to perform a movement selection task involving free-choice and externally-cued trials while applying real/sham tDCS in a C3-C4 dual-hemispheric electrode montage. Contrary to our hypothesis, we did not observe any effect of tDCS on movement selection either at the individual or group level. However, our data confirms the strong preference of right-handed individuals for the dominant right hand. We also found higher reaction time for internally generated movement compared to externally triggered movement. We therefore conclude that movement selection cannot be influenced at the level of primary motor cortex and that brain areas upstream of the primary motor cortex in the voluntary motor pathway may be possible targets for influencing movement selection.

Genetic diversity of the Metarhizium anisopliae complex in Colima, Mexico, using microsatellites.

Metarhizium anisopliae is a complex of cryptic species with wide geographical distribution and versatile lifestyles. In this study, 45 isolates of the Metarhizium genus harbored in the "Colección de Hongos Entomopatógenos" of the "Centro Nacional de Referencia de Control Biológico" from different substrates, insect-host, and localities from Colima, Mexico, were phylogenetically identified using the 5'end of translation elongation factor 1-α (5'TEF) and intergenic nuclear region MzFG543igs. Seven species were recognized, M. acridum (n = 26), M. pemphigi (n = 1), and within the PARB and MGT clades: M. anisopliae (N = 7; sensu stricto: n = 2; sensu lato: n = 5), M. brunneum (n = 2), M. guizhouense (n = 2), M. pingshaense (n = 2), and M. robertsii (n = 5). Twenty-nine SSR markers were developed for M. acridum; according to the analysis of 12 polymorphic SSR loci, M. acridum showed low genetic diversity, revealing five genotypes with a dominant one (n = 21). Based on the analysis of 13 specific SSR loci, 14 genotypes were identified within the PARB and MGT clades. This study contributes to generating valuable information about the community structure and genotypic diversity of Metharhizum species in the state of Colima, Mexico.

Oral intramuscular hemangioma: Report of three cases.

Intramuscular hemangioma (IMH) represents less than 1% of all hemangiomas. In the head and neck region, it occurs mostly in the masseter, temporalis and sternocleidomastoid muscles. Despite its infiltrative growth pattern and several worrisome histological features, such as increased mitotic activity, plumpness of the nuclei, intraluminal papillary projections or perineural infiltration, the lesion is benign, and complete surgical excision is the preferred treatment for such oral lesions. Herein, we report three rare cases of IMH in the tongue and lip, discuss the clinical and histological aspects, and review the literature regarding this lesion.

High genetic diversity of the entomopathogenic fungus Beauveria bassiana in Colima, Mexico.

The entomopathogenic fungus Beauveria bassiana is used widely as a biological control agent against a wide range of insect pests globally. In this study, 44 Beauveria isolates from the state of Colima, Mexico harbored in the "Colección de Hongos Entomopatógenos" of the "Centro Nacional de Referencia de Control Biológico" and from different substrates, insect-hosts, and localities were characterized with molecular markers. All isolates were identified using a Bayesian phylogenetic analysis of translation elongation factor 1-α (TEF) and nuclear intergenic Bloc region. Forty-three isolates were identified as B. bassiana and grouped into two sub-clades, i.e., AFNEO_1 (n = 22; previously defined as a clade with African and Neotropical origin) and Bb clade (n = 21; closely associated with ex-type strain ARSEF 1564), and one isolate was identified as B. pseudobassiana. The fixation index (FST = 0.493) established the genetic differentiation between AFNEO_1 and Bb clades. High genotype richness and genetic diversity of AFNEO_1 and Bb clades were revealed in sequence analysis of Bloc region and SSR genotyping. Moreover, the AFNEO_1 and Bb clades were confirmed as two independent clonally structured assemblages. Finally, the AMOVA detected no significant association between any combination of substrate, insect-host or geographical origin. High genetic variation of B. bassiana in Colima, Mexico could suggest a functional diversity among isolates that may include those effective against a specific insect pest.

Smoking cessation leads to changes in survivin expression in oral mucosa.

BACKGROUND: Survivin is an inhibitor protein of apoptosis and plays a role in oral carcinogenesis mechanism. METHODS: The aim of this study was to evaluate the effect of smoking in survivin expression of oral mucosa of chronic smokers with and without oral squamous cell carcinoma (OSCC). The study was composed of three groups: Group 1-26 patients smoking more than 20 cigarettes/day/10 years without either history of oral malignant neoplasia or visible clinical signs in the examined site; Group 2-26 patients with OSCC; Group 3-22 patients surgically treated for OSCC for at least 1 month. The immunohistochemistry was performed with 1 smear for each group and analyzed by microscopy regarding extension, intensity of positive cells for survivin, and intracellular location. RESULTS: The survivin expression was observed in 100% of the cases in Group 1, 88.5% in Group 2, and 100% in Group 3. Concerning to Groups 1 and 3, the survivin expression with cytoplasmic location occurred in 100%, while in Group 2 occurred in 87.5%. The cytoplasmic and nuclear expression was observed only in Group 2, with 7.69%. The results were correlated with clinical-pathological data by Fischer's exact test with significant relation between smoking cessation and intensity (P = .015) for Group 2. CONCLUSIONS: The extension and intensity of survivin expression in the cytological smears were related to the smoking cessation in the group with OSCC. However, the smoking history (packs/years) did not influence the survivin expression.

Species delimitation of the blue-spotted spiny lizard within a multilocus, multispecies coalescent framework, results in the recognition of a new Sceloporus species.

Species delimitation is a major topic in systematics. Species delimitation methods based on molecular data have become more common since this approach provides insights about species identification via levels of gene flow, the degree of hybridization and phylogenetic relationships. Also, combining multilocus mitochondrial and nuclear DNA leads to more reliable conclusions about species limits. Coalescent-based species delimitation methods explicitly reveal separately evolving lineages using probabilistic approaches and testing the delimitation hypotheses for several species. Within a multispecies, multilocus, coalescent framework, we were able to clarify taxonomic uncertainties within S. cyanostictus, an endangered lizard that inhabits a narrow strip of the Chihuahuan Desert in Mexico. We included, for the first time in a phylogenetic analysis, lizards from the three populations of S. cyanostictus recognized so far (East Coahuila, West Coahuila and Nuevo León). Phylogenetic analysis corroborates the hypothesis of two separately evolving lineages, i.e. the East and West Coahuila populations, as proposed in a previous study. We also found a distant phylogenetic relationship between the lizards from Nuevo León and those of East and West Coahuila. Finally, based on the species delimitation results, we propose and describe a new species of Sceloporus: S. gadsdeni sp. nov.

Protective Effect of Lactobacillus casei on DMH-Induced Colon Carcinogenesis in Mice.

The administration of probiotics is a promising approach to reduce the prevalence of colon cancer, a multifactorial disease, with hereditary factors, as well as environmental lifestyle-related risk factors. Biogenic polyamines, putrescine, spermidine, and spermine are small cationic molecules with great roles in cell proliferation and differentiation as well as regulation of gene expression. Ornithine decarboxylase is the first rate-limiting enzyme for polyamine synthesis, and upregulation of ornithine decarboxylase activity and polyamine metabolism has been associated with abnormal cell proliferation. This paper is focused on studying the protective role of Lactobacillus casei ATCC 393 in a chemically induced mouse model of colon carcinogenesis, directing our attention on aberrant crypt foci as preneoplastic markers, and on polyamine metabolism as a possible key player in carcinogenesis. BALB/c mice were administered 1,2-dimethylhydrazine dihydrochloride (DMH) to induce colon cancer (20 mg/kg body weight, subcutaneous, twice a week for 24 weeks). L. casei ATCC 393 was given orally (106 CFU, twice a week), 2 weeks before DMH administration. Hematoxylin and eosin staining, high-performance liquid chromatography, and Western blotting were used to evaluate aberrant crypt foci, urinary polyamines, and ornithine decarboxylase expression in the colon. The experimental data showed that the preventive administration of L. casei ATCC 393 may delay the onset of cancer as it significantly reduced the number of DMH-induced aberrant crypt foci, the levels of putrescine, and the expression of ornithine decarboxylase. Hence, this probiotic strain has a prospective role in protection against colon carcinogenesis, and its antimutagenic activity may be associated with the maintenance of polyamine metabolism.

Δ6-fatty acid desaturase and fatty acid elongase mRNA expression, phagocytic activity and weight-to-length relationships in channel catfish (Ictalurus punctatus) fed alternative diets with soy oil and a probiotic.

A time-course feeding trial was conducted for 120 days on juvenile channel catfish (Ictalurus punctatus) to study the effects of diets differing in oil source (fish oil or soy oil) and supplementation with a commercial probiotic. Relative levels of Δ6-fatty acid desaturase (Δ6-FAD) and fatty acid elongase (FAE) expression were assessed in brain and liver tissues. Both genes showed similar expression levels in all groups studied. Fish weight-to-length relationships were evaluated using polynomial regression analyses, which identified a burst in weight and length in the channel catfish on day 105 of treatment; this increase was related to an increase in gene expression. Mid-intestinal lactic acid bacterium (LAB) count was determined according to morphological and biochemical criteria using API strips. There was no indication that intestinal LAB count was affected by the modified diets. The Cunningham glass adherence method was applied to evaluate phagocytic cell activity in peripheral blood. Reactive oxygen species (ROS) generation was assessed through the respiratory burst activity of spleen macrophages by the NBT reduction test. Probiotic-supplemented diets provided a good substrate for innate immune system function; the phagocytic index was significantly enhanced in fish fed soy oil and the probiotic, and at the end of the experimental period, ROS production increased in fish fed soy oil. The substitution of fish oil by soy oil is recommended for food formulation and will contribute to promoting sustainable aquaculture. Probiotics are also recommended for channel catfish farming as they may act as immunonutrients.

Hemangiomas hepáticos: aspectos ultra-sonográficos e clínicos / Liver hemangiomas: ultrasound and clinical features

Os hemangiomas são os tumores hepáticos benignos mais comuns, ocorrem em todos os grupos etários, sendo mais comuns nos adultos. Na grande maioria dos casos os hemangiomas são pequenos, assintomáticos e descobertos incidentalmente. Lesões maiores eventualmente podem produzir sintomas. O aspecto ultra-sonográfico desses tumores varia, sendo que o aspecto usual é o de lesão pequena hiperecogênica bem definida. Neste artigo, os autores fazem uma revisão sobre aspectos clínicos e ultra-sonográficos dos hemangiomas, ressaltando a importância desses aspectos na condução clínica dos pacientes acometidos.

Hemangiomas are the most common benign tumors of the liver, occurring in all age groups, and more frequently in adults. The vast majority of hemangiomas are small, asymptomatic, and are incidentally discovered. Larger lesions may eventually produce symptoms. The sonographic aspect of these tumors varies, the lesions being typically small, well defined and hyperechoic. In this study the authors review clinical and sonographic features of hemangiomas, highlighting the clinical significance of such features to be taken into consideration in the treatment of affected patients.

[Laparoscopic hysterectomy in the surgical treatment of gynecological malignant and premalignant diseases]. / Histerectomía laparoscópica en el tratamiento quirúgico de enfermedades ginecológicas malignas y premalignas.

INTRODUCTION: Laparoscopic hysterectomy (LH) is a safe surgical approach that offers patients a faster recovery. However, its use in malignant or premalignant gynecological lesions is not well established. The objective of the present study was to show the feasibility of LH in a tertiary cancer center. MATERIAL AND METHODS: We conducted a descriptive analysis of patients with histologically proven malignant or premalignant uterine lesions who underwent to LH. Surgical time, bleeding complications, and hospital stay were evaluated. RESULTS: Twenty-five patients were included with a mean age of 45 years. Ten LH (40%) with or without salpingo-oophorectomy for premalignant or preinvasive malignant lesions were done, five surgical staging procedures for endometrial cancer (20%) and seven radical hysterectomies for cervical cancer (28%). In three patients, conversion from laparotomy (12%) was necessary for operative complications (two cases) or technical problems (one case). Mean operative time for the entire group was 207 min, mean bleeding 204 mL and mean hospital stay was 2.5 days. Postoperative complications were present in two patients, hematoma in the vaginal cupola (one case) and temporary bladder dysfunction (one case). CONCLUSIONS: In the present trial we described our initial experience in LH for the treatment of malignant and premalignant gynecologic diseases. Our results suggest that it is a safe and feasible surgical approach. Long-term surveillance studies are necessary for the evaluation of recurrence patterns and overall survival.

Reduced levels of uridine diphosphate glucose pyrophosphorylase activity in fetal and neonatal human and guinea pig liver.

Uridine diphosphate glucose pyrophosphorylase (UDPGPP) is the first enzyme in the bilirubin conjugation pathway. A study aiming to screen for red blood cell UDPGPP deficiency in newborns with hyperbilirubinemia was carried out. No individuals with severe UDPGPP deficiency were found, however, levels of UDPGPP in premature and at term newborns were lower than in adults. These findings led to the study of UDPGPP in human fetal, neonatal and adult liver, using guinea pig tissues as a parallel control. UDPGPP activities in fetal and neonatal samples were also significantly lower than in adult ones in both species. Therefore, it is postulated that the reduced levels of UDPGPP in fetal and neonatal liver could be a factor which contributes to the pathogenesis of the physiologic jaundice in human newborns.

De novo del(4) (p15.32) with incomplete expression of the Wolf-Hirschhorn syndrome.

A 7 7/12-year-old girl with a de novo deletion 4p15.32----pter without the typical Wolf-Hirschhorn syndrome (WHS) is presented. This observation and others from medical literature suggest that monosomy 4p15.31----4p15.32, rather than 4p16, is the cause of the typical WHS.