Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Int J Mol Sci ; 24(22)2023 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-38003692

RESUMEN

Cirrhosis is the end result of liver fibrosis in chronic liver diseases. Studying the mechanisms of its development and developing measures to slow down and regress it based on this knowledge seem to be important tasks for medicine. Currently, disorders of the gut-liver axis have great importance in the pathogenesis of cirrhosis. However, gut dysbiosis, which manifests as increased proportions in the gut microbiota of Bacilli and Proteobacteria that are capable of bacterial translocation and a decreased proportion of Clostridia that strengthen the intestinal barrier, occurs even at the pre-cirrhotic stage of chronic liver disease. This leads to the development of bacterial translocation, a process by which those microbes enter the blood of the portal vein and then the liver tissue, where they activate Kupffer cells through Toll-like receptor 4. In response, the Kupffer cells produce profibrogenic cytokines, which activate hepatic stellate cells, stimulating their transformation into myofibroblasts that produce collagen and other elements of the extracellular matrix. Blocking bacterial translocation with antibiotics, probiotics, synbiotics, and other methods could slow down the progression of liver fibrosis. This was shown in a number of animal models but requires further verification in long-term randomized controlled trials with humans.


Asunto(s)
Microbioma Gastrointestinal , Hepatopatías , Animales , Humanos , Traslocación Bacteriana , Cirrosis Hepática/patología , Hígado/patología , Hepatopatías/patología , Disbiosis/microbiología
2.
Front Oncol ; 13: 1197287, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601694

RESUMEN

Background: The global incidence of lip and oral cavity cancers (OCCs) and oropharyngeal cancers (OPCs) is steadily increasing. While tobacco and alcohol consumption are established risk factors, a considerable proportion of these cancers has become attributed to human papilloma virus (HPV) infection. We aimed to describe the occurrence and identify potential risk factors of OCCs and OPCs across the Russian Federation during 2007-2018. Methods: We conducted an ecological analysis using publicly accessible data from the P.A. Herzen Moscow Oncology Research Institute. Incidence and mortality rates by jurisdiction were mapped for geospatial analysis. We pre-defined 11 potential contributing risk factors and used univariable and multivariable Poisson regression model with backwards stepwise variable selection to identify associated factors with OCC and OPC. Results: A total of 190,585 individuals were diagnosed with OCCs and OPCs in Russia between 2007-2018. Non-uniform geographic distribution of cancer cases was noted where the Far Eastern Federal District had the highest rate of OCC and the Central Federal District of OPCs. Districts with high weekly alcohol consumption had significantly higher incidence and mortality rates in both sexes. Districts with high rates of daily smoking had higher incidence of OCC among females, and those with low smoking trends had lower mortality rates for OCCs and OPCs. Conclusion: We detail the burden of OCCs and OPCs across Russia, with the aim of elucidating modifiable risk factors and proposing evidence-based prevention strategies. Tobacco/alcohol sales control measures and smoking/drinking cessation programs should continue to be prioritized as public health measures, especially for females.

3.
Curr Oncol ; 30(6): 5631-5651, 2023 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-37366907

RESUMEN

Sarcomas are a heterogeneous group of mesenchymal malignancies with various genetic and environmental risk factors. This study analyzed the epidemiology of sarcomas to gain insight into the incidence and mortality rates of these cancers in Canada, as well as to elucidate their potential environmental risk factors. Data for this study were obtained from le Registre Québécois du Cancer (LRQC) and from the Canadian Cancer Registry (CCR) for the period from 1992 to 2010. Mortality data were obtained from the Canadian Vital Statistics (CVS) database for the period from 1992 to 2010 using the International Classification of Diseases for Oncology, ICD-O-3, ICD-9, or ICD-10 codes, for all subtypes of sarcomas. We found that the overall sarcoma incidence in Canada decreased during the study period. However, there were select subtypes with increasing incidence. Peripherally located sarcomas were found to have lower mortality rates compared to axially located sarcomas, as expected. Clustering of Kaposi sarcoma cases in self-identified LGBTQ+ communities and in postal codes with a higher proportion of African-Canadian and Hispanic populations was observed. Forward Sortation Area (FSA) postal codes with a lower socioeconomic status also had higher Kaposi sarcoma incidence rates.


Asunto(s)
Sarcoma de Kaposi , Sarcoma , Neoplasias de los Tejidos Blandos , Humanos , Canadá/epidemiología , Incidencia , Neoplasias de los Tejidos Blandos/epidemiología , Sarcoma/epidemiología
4.
Lancet Reg Health Eur ; 20: 100454, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35813967

RESUMEN

Background: Cervical cancer is one of the leading causes of cancer in women of childbearing age worldwide. A substantial fraction of cervical cancer is associated with Human Papilloma Virus (HPV) infection and is preventable through vaccination and screening. The aim of the study is to describe geographic and epidemiologic trends in incidence and mortality of cervical cancer in Russia during 2007-2018. Methods: Publicly accessible data from the P.A. Herzen Moscow Oncology Research Institute and the Ministry of Health of Russian Federation for 2007-2018 was used for this study. Cervical cancer incidence and mortality rates were analyzed using descriptive statistics and results were mapped to determine the geographic distribution. Potential contributing risk factors in the population were studied using univariate and multivariate Poisson regression analyses. Findings: A total of 187,013 patients were diagnosed with cervical cancer in Russia between 2007 and 2018. The average age-standardized incidence (ASIR) and mortality rates (ASMR) were 15.70/100,000 and 5.76/100,000 females, respectively, with a 27% increase in the incidence observed between 2007 and 2018. The highest ASIR was observed in the Far Eastern Federal District and the lowest in the Central Federal District. Multivariate model for cervical cancer ASIR showed that daily smoking (p = 0·0003) and syphilis (p = 0.003) were significantly associated with cervical cancer incidence. Interpretation: The incidence of cervical cancer in Russia is rising at a significant pace. This trend can in part be attributed to a lack of nationwide cervical cancer screening . The presented results are valuable for informing public health policy on HPV vaccinations, smoking prevention and cervical cancer screening as urgent interventions are needed to combat a troubling trend. Funding: This work was supported by the Cancer Research Society (CRS)-Canadian Institutes for Health Research (CIHR) Partnership Grant #25343 to Dr. Litvinov. Canadian Dermatology Foundation research grant to Dr. Litvinov, and by the Fonds de la recherche du Québec - Santé to Dr. Sasseville (#22648) and to Dr. Litvinov (#34753 and #36769). This research was further supported by the CIHR Catalyst Grant #428712 to Dr. Litvinov.

5.
Molecules ; 27(11)2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35684337

RESUMEN

Bile acids are specific and quantitatively important organic components of bile, which are synthesized by hepatocytes from cholesterol and are involved in the osmotic process that ensures the outflow of bile. Bile acids include many varieties of amphipathic acid steroids. These are molecules that play a major role in the digestion of fats and the intestinal absorption of hydrophobic compounds and are also involved in the regulation of many functions of the liver, cholangiocytes, and extrahepatic tissues, acting essentially as hormones. The biological effects are realized through variable membrane or nuclear receptors. Hepatic synthesis, intestinal modifications, intestinal peristalsis and permeability, and receptor activity can affect the quantitative and qualitative bile acids composition significantly leading to extrahepatic pathologies. The complexity of bile acids receptors and the effects of cross-activations makes interpretation of the results of the studies rather difficult. In spite, this is a very perspective direction for pharmacology.


Asunto(s)
Ácidos y Sales Biliares , Cuerpo Humano , Bilis , Hepatocitos , Humanos , Hígado/fisiología
6.
Molecules ; 27(6)2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35335345

RESUMEN

Bile acids are important physiological agents required for the absorption, distribution, metabolism, and excretion of nutrients. In addition, bile acids act as sensors of intestinal contents, which are determined by the change in the spectrum of bile acids during microbial transformation, as well as by gradual intestinal absorption. Entering the liver through the portal vein, bile acids regulate the activity of nuclear receptors, modify metabolic processes and the rate of formation of new bile acids from cholesterol, and also, in all likelihood, can significantly affect the detoxification of xenobiotics. Bile acids not absorbed by the liver can interact with a variety of cellular recipes in extrahepatic tissues. This provides review information on the synthesis of bile acids in various parts of the digestive tract, its regulation, and the physiological role of bile acids. Moreover, the present study describes the involvement of bile acids in micelle formation, the mechanism of intestinal absorption, and the influence of the intestinal microbiota on this process.


Asunto(s)
Ácidos y Sales Biliares , Metabolismo de los Lípidos , Ácidos y Sales Biliares/metabolismo , Hígado/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Transducción de Señal/fisiología
7.
Nutrients ; 13(9)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34579083

RESUMEN

Histamine is a natural amine derived from L-histidine. Although it seems that our knowledge about this molecule is wide and diverse, the importance of histamine in many regulatory processes is still enigmatic. The interplay between different types of histamine receptors and the compound may cause ample effects, including histamine intoxication and so-called histamine intolerance or non-allergic food intolerance, leading to disturbances in immune regulation, manifestation of gastroenterological symptoms, and neurological diseases. Most cases of clinical manifestations of histamine intolerance are non-specific due to tissue-specific distribution of different histamine receptors and the lack of reproducible and reliable diagnostic markers. The diagnosis of histamine intolerance is fraught with difficulties, in addition to challenges related to the selection of a proper treatment strategy, the regular course of recovery, and reduced amelioration of chronic symptoms due to inappropriate treatment prescription. Here, we reviewed a history of histamine uptake starting from the current knowledge about its degradation and the prevalence of histamine precursors in daily food, and continuing with the receptor interactions after entering and the impacts on the immune, central nervous, and gastrointestinal systems. The purpose of this review is to build an extraordinarily specific method of histamine cycle assessment in regard to non-allergic intolerance and its possible dire consequences that can be suffered.


Asunto(s)
Intolerancia Alimentaria , Enfermedades Gastrointestinales/metabolismo , Histamina/metabolismo , Regulación de la Expresión Génica , Humanos
8.
Molecules ; 26(12)2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34207319

RESUMEN

Folates have a pterine core structure and high metabolic activity due to their ability to accept electrons and react with O-, S-, N-, C-bounds. Folates play a role as cofactors in essential one-carbon pathways donating methyl-groups to choline phospholipids, creatine, epinephrine, DNA. Compounds similar to folates are ubiquitous and have been found in different animals, plants, and microorganisms. Folates enter the body from the diet and are also synthesized by intestinal bacteria with consequent adsorption from the colon. Three types of folate and antifolate cellular transporters have been found, differing in tissue localization, substrate affinity, type of transferring, and optimal pH for function. Laboratory criteria of folate deficiency are accepted by WHO. Severe folate deficiencies, manifesting in early life, are seen in hereditary folate malabsorption and cerebral folate deficiency. Acquired folate deficiency is quite common and is associated with poor diet and malabsorption, alcohol consumption, obesity, and kidney failure. Given the observational data that folates have a protective effect against neural tube defects, ischemic events, and cancer, food folic acid fortification was introduced in many countries. However, high physiological folate concentrations and folate overload may increase the risk of impaired brain development in embryogenesis and possess a growth advantage for precancerous altered cells.


Asunto(s)
Ácido Fólico/metabolismo , Animales , Encéfalo/metabolismo , Desarrollo Embrionario/fisiología , Deficiencia de Ácido Fólico/metabolismo , Humanos , Neoplasias/metabolismo , Lesiones Precancerosas/metabolismo
9.
HPB (Oxford) ; 23(10): 1541-1549, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33863655

RESUMEN

BACKGROUND: Gallbladder and biliary tract cancers are rare malignancies that carry a poor prognosis. Research on their epidemiologic trends is scarce. METHODS: We performed a retrospective analysis of the data in Canada using population-based cancer registries from 1992 to 2010. The incidence and mortality of gallbladder and extrahepatic bile duct cancers were examined at the levels of provinces/territories, cities, and Forward Sortation Area (FSA) postal codes. RESULTS: The incidence and mortality rates decreased over the study period. The average national incidence rate of gallbladder and biliary tract cancers was 30.92 cases per million individuals per year. Higher than average incidence rates were observed in Manitoba, Saskatchewan and Québec; there were contiguous regions with high incidence in Saskatchewan and Manitoba that suggest an area of putative case clustering. Higher incidence of gallbladder cancer was observed in women, whereas higher incidence of extrahepatic bile duct cancers was noted in men. Lower socioeconomic status and Hispanic race were found to be risk factors for gallbladder and biliary tract cancers. CONCLUSION: This is the first study to analyze the burden of gallbladder and biliary tract cancers in Canada. The geographic clustering trends present new avenues for research on environmental triggers.


Asunto(s)
Conductos Biliares Extrahepáticos , Neoplasias del Sistema Biliar , Neoplasias de la Vesícula Biliar , Neoplasias del Sistema Biliar/diagnóstico , Neoplasias del Sistema Biliar/epidemiología , Canadá/epidemiología , Femenino , Vesícula Biliar , Neoplasias de la Vesícula Biliar/epidemiología , Humanos , Incidencia , Masculino , Estudios Retrospectivos
10.
Front Hum Neurosci ; 7: 293, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23847490

RESUMEN

The relationships between the anatomical representation of semantic knowledge in the human brain and the timing of neurophysiological mechanisms involved in manipulating such information remain unclear. This is the case for superordinate semantic categorization-the extraction of general features shared by broad classes of exemplars (e.g., living vs. non-living semantic categories). We proposed that, because of the abstract nature of this information, input from diverse input modalities (visual or auditory, lexical or non-lexical) should converge and be processed in the same regions of the brain, at similar time scales during superordinate categorization-specifically in a network of heteromodal regions, and late in the course of the categorization process. In order to test this hypothesis, we utilized electroencephalography and event related potentials (EEG/ERP) with functional magnetic resonance imaging (fMRI) to characterize subjects' responses as they made superordinate categorical decisions (living vs. non-living) about objects presented as visual pictures or auditory words. Our results reveal that, consistent with our hypothesis, during the course of superordinate categorization, information provided by these diverse inputs appears to converge in both time and space: fMRI showed that heteromodal areas of the parietal and temporal cortices are active during categorization of both classes of stimuli. The ERP results suggest that superordinate categorization is reflected as a late positive component (LPC) with a parietal distribution and long latencies for both stimulus types. Within the areas and times in which modality independent responses were identified, some differences between living and non-living categories were observed, with a more widespread spatial extent and longer latency responses for categorization of non-living items.

11.
PLoS One ; 3(6): e2349, 2008 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-18545651

RESUMEN

Tune deafness (TD) is a central auditory processing disorder characterized by the inability to discriminate pitch, reproduce melodies or to recognize deviations in melodic structure, in spite of normal hearing. The cause of the disorder is unknown. To identify a pathophysiological marker, we ascertained a group of severely affected TD patients using the Distorted Tunes Test, an ecologically valid task with a longstanding history, and used electrophysiological methods to characterize the brain's responses to correct and incorrect melodic sequences. As expected, we identified a neural correlate of patients' unawareness of melodic distortions: deviant notes modulated long-latency auditory evoked potentials and elicited a mismatch negativity in controls but not in affected subjects. However a robust P300 was elicited by deviant notes, suggesting that, as in blindsight, TD subjects process stimuli that they cannot consciously perceive. Given the high heritability of TD, these patients may make it possible to use genetic methods to study cellular and molecular mechanisms underlying conscious awareness.


Asunto(s)
Concienciación , Potenciales Evocados Auditivos , Trastornos del Desarrollo del Lenguaje/fisiopatología , Música , Humanos
12.
Int J Neurosci ; 112(5): 587-606, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12325392

RESUMEN

Functional magnetic resonance imaging was used to investigate preattentive and attentional processing of auditory stimuli in 18 right-handed normal volunteers. Responses to trains of 1000-Hz pure tones and infrequent (15%) deviant 1300-Hz tones were characterized while subjects ignored all tones; listened for deviants in the left ear; or listened for deviants in the right ear. Preattentive detection of deviants, associated with the mismatch negativity in electrophysiology, was associated with bilateral temporal lobe activation, with a rightward predominance. Processing of deviant stimuli while attending to either ear produced a more robust and widespread activation of these temporal regions, again with a rightward predominance. Thus, preattentive tone processing appears to be linked to asymmetric activation of a core set of temporal regions in which activity is significantly amplified by selective attention. Extratemporal regions activated by attending to targets in either ear included the anterior cingulate cortex, supramarginal gyrus, and dorsolateral prefrontal cortex.


Asunto(s)
Atención/fisiología , Corteza Auditiva/fisiología , Percepción Auditiva/fisiología , Estimulación Acústica , Adulto , Potenciales Evocados Auditivos/fisiología , Femenino , Lateralidad Funcional/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Lóbulo Temporal/fisiología
13.
Hum Brain Mapp ; 16(3): 168-75, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12112770

RESUMEN

We performed an fMRI one-back recognition study aimed at distinguishing the semantic versus perceptual aspects of how objects and their written forms are processed. There were three types of visually presented items: pictures (schematic drawings of objects); words identifying these objects; and a mixed condition in which pictures were interleaved with words. A semantic decision about object identity was required when pictures were interleaved with words. This condition, contrasted with the other two, invoked a larger signal in multiple areas, including frontal cortex, bilateral occipitotemporal cortex, and the right middle temporal gyrus. We propose that the left occipitotemporal and right temporal activations are indicative of the neural substrate mediating picture-word conversions, whereas the frontal activations reflect the coordinating functions of the central executive.


Asunto(s)
Corteza Cerebral/fisiología , Lateralidad Funcional/fisiología , Memoria a Corto Plazo/fisiología , Red Nerviosa/fisiología , Reconocimiento Visual de Modelos/fisiología , Semántica , Habla/fisiología , Adulto , Mapeo Encefálico , Corteza Cerebral/anatomía & histología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Estimulación Luminosa
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...