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Resumen La investigación moderna, tanto en humanos como preclínica, que utiliza modelos animales indica que fumar durante la edad adolescente resulta en cambios cerebrales y psicológicos a corto y largo plazo en el fumador, así como en un aumento significativo en los riesgos de desarrollar adicción al tabaco durante la vida. Por lo tanto, en la presente revisión narrativa se describirán y profundizarán los hallazgos investigativos modernos de la psicobiología de la adolescencia y los efectos del tabaco en el desarrollo, con un énfasis particular en la comprensión de los efectos psicológicos y cerebrales del consumo de tabaco durante la adolescencia, tanto a corto como a largo plazo. Se considerarán de manera detallada los avances investigativos sobre la psicobiología de la adolescencia y sus riesgos en las adicciones desde los aspectos: conductual, cognitivo, reactividad al estrés y psicobiología. Sobre esta base, se revisará la investigación sobre la psicobiología de la adolescencia y la evidencia de vulnerabilidad a la adicción durante esta etapa. Al final, se abordarán los efectos del tabaco en el cerebro y conducta durante el desarrollo adolescente y vida posterior, ya que se ha encontrado evidencia relacionada con alteraciones cerebrales crónicas en los sistemas colinérgicos y regiones cerebrales asociadas con la dependencia de la nicotina. Se espera que la revisión y divulgación de esta información en el idioma español sea de valor para la comprensión de los problemas de vulnerabilidad y predisposiciones a la adicción al tabaco en el contexto de Latinoamérica.
Abstract Tobacco use and its harmful health-related problems have become one of the largest modern preventable public health issues. Current research strongly suggests that smoking during adolescence enhances addictive smoking behaviors during life, which can be related to adolescence as a critical ontogenetic period characterized by behaviors that can increase the probability of risk-related behaviors such as sensation and novelty seeking. Adolescent development is also a period of maturation of frontal and subcortical neural systems, brain changes that underlie higher impulsivity tendencies to promote adequate learning and adaptations necessary to succeed the novel challenges of the adult life, but those changes also enhance vulnerabilities to the addictive effects of drugs. Consistent with this, tobacco use affects brain development processes which underlie long-term psychobiological alterations and the enhanced risks for tobacco addiction during adult life. Thus, the present review describes current psychobiological approaches to understand general addiction processes and tobacco addiction, highlighting the behavioral and neural short-term effects of tobacco use during adolescence and its long-term effects during adulthood. Current research has advanced on four aspects for the understanding of both the psychobiology of adolescent development and the effects of drugs of abuse during this time. The first aspect is behavioral, as adolescence is related to important changes on motivational and emotional behaviors such as sensation seeking. Other important behavioral changes are social approach, a higher variety of opportunity for personal choices, and development of personal independence. Research on a second aspect has focused on cognition. A review of research is presented showing enhanced abilities during adolescence development for reading, abstract and logical thinking, and novel problem solving. Stress reactivity is the third aspect of reviewed psychobiological mechanisms. The stress biological system undergoes important changes during adolescence, including changes on stress-related hormones and neural architecture. An important issue is that exposure to early and/or chronic stressful circumstances during adolescence could be related to higher risk to the start and maintenance of addiction states, as suggested by research assessing the disruptive effects of stress on psychobiological homeostatic processes needed to maintain stable biological and emotional regulation. The fourth aspect is psychobiology. In this section research is reviewed related to the development of monoaminergic brain circuits underlying motivation, novelty-seeking, impulsivity, and addiction processes. Using as model the previous review integration, the effects of nicotine are discussed, the essential addictive component of tobacco, on the neurochemical systems underlying tobacco addiction. Following this, important research is introduced that describes psychobiological changes during adolescence and evidence of vulnerability to addiction during this life stage. Then, current research on both short-term and long-term effects of tobacco or nicotine administration during adolescence on the brain, behavior, and cognition is introduced. The current research advances and discussions on the psychobiology of addictions in general, and tobacco addiction in particular, have been possible to a large extent from the use of animal models and preclinical research, since animal models have become crucial to identify learning, motivational, emotional, and cognitive mechanisms that underlie addictive processes, and making possible to perform experimental procedures to discover the functioning and participation of biological components. One example of such components is the cholinergic system, which is activated by nicotine and is part of the neurochemical machinery on different brain areas important for both tobacco addiction and adolescence development such as the dorsal striatum, amygdala, ventral tegmental area, nucleus accumbens, prefrontal cortex, and hippocampus. The present review and research divulgation written in Spanish are expected to clarify modern research on addiction and encourage current scientific education on the vulnerabilities and predispositions for tobacco abuse in Latin-American countries.
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BACKGROUND: Healthcare Workers (HCW) are repeatedly exposed to SARS-CoV-2 infection. The aim of this study was to identify factors associated with SARS-CoV-2 infection among HCW in one of the largest cities in Colombia. METHODS: We conducted a case-control study, where cases had a positive reverse transcription-polymerase chain reaction and controls had a negative result. Participants were randomly selected and interviewed by phone. Analyses were performed using logistic regression models. RESULTS: A total of 110 cases and 113 controls were included. Men (AdjOR 4.13 95% CI 1.70-10.05), Nurses (AdjOR 11.24 95% CI 1.05-119.63), not using a high-performance filtering mask (AdjOR 2.27 95% CI 1.02-5.05) and inadequate use of personal protective equipment (AdjOR 4.82 95% CI 1.18-19.65) were identified as risk factors. Conversely, graduate (AdjOR 0.06 95% CI 0.01-0.53) and postgraduate (AdjOR 0.05 95% CI 0.005-0.7) education, feeling scared or nervous (AdjOR 0.45 95% CI 0.22-0.91), not always wearing any gloves, caps and goggles/face shields (AdjOR 0.10 95% CI 0.02-0.41), and the use of high-performance filtering or a combination of fabric plus surgical mask (AdjOR 0.27 95% CI 0.09-0.80) outside the workplace were protective factors. CONCLUSION: This study highlights the protection provided by high-performance filtering masks or double masking among HCW. Modifiable and non-modifiable factors and the difficulty of wearing other protective equipment needs to be considered in designing, implementing and monitoring COVID-19 biosafety protocols for HCW.
Subject(s)
COVID-19 , SARS-CoV-2 , Case-Control Studies , Colombia/epidemiology , Health Personnel , Humans , MaleABSTRACT
CONTEXT: Nowadays, complementary therapies are necessary for a major removal of microbial subgingival biofilm in the conventional treatment of periodontitis. Research has suggested the use of photodynamic therapy (PDT) as a promising therapy to manage oral cavity infections. This project proposes a new combination of photosensitizer chloroaluminum phthalocyanine and nanoemulsion as a strategy for improving bioactivity. The main purpose of this in vitro study was to evaluate the antimicrobial activity of nanoemulsion ClAlPc (ClAlPc-NE) on relevant periodontal bacteria before and after PDT. MATERIALS AND METHODS: The phototoxic and antibacterial effect of ClAlPc-NE was evaluated against epithelial cells derived from an African green monkey kidney using the colorimetric method with salt tetrazolium 3-(4.5-dimethylthiazolyl-2)-2.5-Diphenyltetrazolium bromide (Merck) and periodontopathogen bacteria (Porphyromonas gingivalis (ATCC 33277), Aggregatibacter actinomycetemcomitans (ATCC 33384), and Prevotella intermedia (ATCC 25611) using the plate microdilution method according to Tavares et al., 2018, respectively. The light source used for the PDT was a LED laser (400-700 nm); the cells were irradiated for 2 min using 4.83 joules/cm2. RESULTS: Antibacterial effect of NE-PcAlCl against P. intermedia with minimum inhibitory concentration (MIC) 0.63 µM after TFD was determined. In the case of P. gingivalis and A. actinomycetemcomitans, no biological activity was found after PDT (MIC > 20 µM) under-evaluated experimental conditions. On the other hand, the ClAlPc-free and ClAlPc-NE cells were phototoxic on epithelial cells. CONCLUSION: The results helped to identify the potential use of ClAlPc-NE to inhibit the periodontal bacterial and additional studies are being developed.
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The disease caused by the new SARS-CoV-2, known as Coronavirus disease 2019 (COVID-19), was first identified in China in December 2019 and rapidly spread around the world. Coinfections with fungal pathogens in patients with COVID-19 add challenges to patient care. We conducted a literature review on fungal coinfections in patients with COVID-19. We describe a report of a patient with disseminated histoplasmosis who was likely infected with SARS-CoV-2 and experienced COVID-19 during hospital care in Buenos Aires, Argentina. This patient presented with advanced HIV disease, a well-known factor for disseminated histoplasmosis; on the other hand, we suspected that COVID-19 was acquired during hospitalization but there is not enough evidence to support this hypothesis. Clinical correlation and the use of specific Histoplasma and COVID-19 rapid diagnostics assays were key to the timely diagnosis of both infections, permitting appropriate treatment and patient care.
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Transforming growth factor ß (TGF-ß) has been shown to play a role in immunity against different pathogens in vitro and against parasites in vivo However, its role in viral infections in vivo is incompletely understood. Using a neonatal mouse model of heterologous rhesus rotavirus (RV) vaccination, we show that the vaccine induced rotavirus-specific CD4 T cells, the majority of which lacked expression of KLRG1 or CD127, and a few regulatory rotavirus-specific CD4 T cells that expressed surface latency-associated peptide (LAP)-TGF-ß. In these mice, inhibiting TGF-ß, with both a neutralizing antibody and an inhibitor of TGF-ß receptor signaling (activin receptor-like kinase 5 inhibitor [ALK5i]), did not change the development or intensity of the mild diarrhea induced by the vaccine, the rotavirus-specific T cell response, or protection against a subsequent challenge with a murine EC-rotavirus. However, mice treated with anti-LAP antibodies had improved protection after a homologous EC-rotavirus challenge, compared with control rhesus rotavirus-immunized mice. Thus, oral vaccination with a heterologous rotavirus stimulates regulatory RV-specific CD4 LAP-positive (LAP+) T cells, and depletion of LAP+ cells increases vaccine-induced protection.IMPORTANCE Despite the introduction of several live attenuated animal and human rotaviruses as efficient oral vaccines, rotaviruses continue to be the leading etiological agent for diarrhea mortality among children under 5 years of age worldwide. Improvement of these vaccines has been partially delayed because immunity to rotaviruses is incompletely understood. In the intestine (where rotavirus replicates), regulatory T cells that express latency-associated peptide (LAP) play a prominent role, which has been explored for many diseases but not specifically for infectious agents. In this paper, we show that neonatal mice given a live oral rotavirus vaccine develop rotavirus-specific LAP+ T cells and that depletion of these cells improves the efficiency of the vaccine. These findings may prove useful for the design of strategies to improve rotavirus vaccines.
Subject(s)
CD4-Positive T-Lymphocytes/immunology , Rotavirus Infections/prevention & control , Rotavirus Vaccines/immunology , T-Lymphocyte Subsets/immunology , Transforming Growth Factor beta/analysis , Administration, Oral , Animals , Animals, Newborn , CD4-Positive T-Lymphocytes/chemistry , Diarrhea/prevention & control , Disease Models, Animal , Immunity, Heterologous , Mice , Rotavirus Vaccines/administration & dosage , T-Lymphocyte Subsets/chemistry , Treatment OutcomeABSTRACT
We had the challenged to treat a 40-year-old female with Systemic Scleroderma who was showing unspecific symptoms. During her time at the hospital she rapidly develops renal dysfunction, associated with hypertension. She required renal replacement therapy initiation and we observed a decline in hemoglobin and platelets numbers. We confirm a microangiopathic hemolytic anemia and rule out other immune diseases or thrombotic thrombocytopenic purpura. Systemic Sclerosis is a chronic immune disorder of unknown origin that it is not completely understood. It is believed that environmental factors may contribute and also altered genes may be implicated in the immune system's function. Microangiopathic hemolytic anemia occurs in 43% of patients who develop scleroderma renal crisis and an activation of the complement system through the classical pathway may be involved. Given that context we decided to treat the patients with C5 blocker Eculizumab and obtain an extraordinary positive response.
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La transición epitelio mesénquima (EMT) es un proceso compuesto de diferentes fases, donde una célula epitelial adquiere un fenotipo mesenquimal. Dentro de los cambios involucrados se encuentran: pérdida de la polaridad celular, adquisición de una capacidad migratoria, capacidad invasora, resistencia a la apoptosis y aumento en la producción de componentes de la matriz extracelular. Todos estos cambios ocurren como una consecuencia de la activación y represión de genes involucrados con rutas de señalización específicas relacionadas con este evento. La EMT está relacionada con procesos fisiológicos y patológicos como el cáncer. Consta de tres fases: una de células no migratorias, células premigratorias y células migratorias; cada una de ellas producto de diferentes señales intra o extracelulares, factores de transcripción (TGF-B, Snail, TWIST, Sox, Slug, ZEB1, entre otras) y proteínas involucradas (E-cadherina, integrina, vimentina, ocludinas y claudinas).
Transition mesenchymal epithelium (EMT) is a process composed of different phases where an epithelial cell acquires a mesenchymal phenotype. Among the changes involved are: loss of cellular polarity, acquisition of a migratory capacity, invasive capacity, resistance to apoptosis, and increase in the production of components of the extracellular matrix. All these changes occur as a consequence of the activation and repression of genes involved with specific signaling pathways related to this event. EMT is related to physiological and pathological processes such as cancer. It consists of three phases: A phase of non-migratory cells, pre-migratory cells and migratory cells; (TGF-B, Snail, TWIST, Sox, Slug, ZEB1 among others), and proteins involved (E-cadherin, integrin, vimentin, occludins and claudins).
Subject(s)
Humans , Epithelial Cells , Mesenchymal Stem CellsABSTRACT
Philodryas olfersii is found in South America, from Amazonas to Patagonia. It is important to characterize the venom of P. olfersii, who inhabits the North-East region of Argentina, since snake venoms are known to exhibit considerable variability in composition and biological activities. In this work, mice weighing 18-20 g (n = 4 for each experimental group) were used. For the edematogenic activity mice were injected s.c. in the right foot pad with 50 microl of solutions containing different amounts of venom, whereas the left foot pad was injected with 50 microl of PBS. Two hours after injection mice were killed by cervical dislocation and both feet were cut off and weighed individually. For the myotoxic activity mice were injected i.m. with 100 microl of solutions containing 40 microg of venom. Blood samples were extracted after 1, 3, 6, 8, 10, 12, 14, 16 and 24 h of venom injection to determinate serum CPK activity and mice were sacrificed at the same time intervals to obtain the inoculated gastrocnemius muscle. They were fixed with Bouin solution and stained with Hematoxylin-Eosin. Results showed that P. olfersii venom exhibits a high edematogenic activity (MED = 0.31 microg) and a moderate myotoxic activity. Myonecrosis reached its highest level after 12 h of venom injection as shown by plasmatic CPK levels (5,401 +/- 330 IU/l) and microscopic assay. It demonstrates the potential toxicity of the venom of P. olfersii, who inhabits the North-East region of Argentina. It also reinforces the original warning concerning the potential danger of bites by colubrids.
Subject(s)
Colubridae/physiology , Edema/chemically induced , Muscle, Skeletal/drug effects , Snake Venoms/toxicity , Animals , Argentina , Colubridae/anatomy & histology , Creatine Kinase/blood , Edema/physiopathology , Hemorrhage/chemically induced , Hemorrhage/physiopathology , Mice , Muscle, Skeletal/pathology , Muscle, Skeletal/physiopathology , Necrosis , Reaction Time/physiology , Salivary Glands/metabolismABSTRACT
Philodryas olfersii is found in South America, from Amazonas to Patagonia. It is important to characterize the venom of P. olfersii, who inhabits the North-East region of Argentina, since snake venoms are known to exhibit considerable variability in composition and biological activities. In this work, mice weighing 18-20 g (n = 4 for each experimental group) were used. For the edematogenic activity mice were injected s.c. in the right foot pad with 50 microl of solutions containing different amounts of venom, whereas the left foot pad was injected with 50 microl of PBS. Two hours after injection mice were killed by cervical dislocation and both feet were cut off and weighed individually. For the myotoxic activity mice were injected i.m. with 100 microl of solutions containing 40 microg of venom. Blood samples were extracted after 1, 3, 6, 8, 10, 12, 14, 16 and 24 h of venom injection to determinate serum CPK activity and mice were sacrificed at the same time intervals to obtain the inoculated gastrocnemius muscle. They were fixed with Bouin solution and stained with Hematoxylin-Eosin. Results showed that P. olfersii venom exhibits a high edematogenic activity (MED = 0.31 microg) and a moderate myotoxic activity. Myonecrosis reached its highest level after 12 h of venom injection as shown by plasmatic CPK levels (5,401 +/- 330 IU/l) and microscopic assay. It demonstrates the potential toxicity of the venom of P. olfersii, who inhabits the North-East region of Argentina. It also reinforces the original warning concerning the potential danger of bites by colubrids.
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Uma nova espécie de Sibynomorphus é descrita com base em material proveniente das províncias argentinas de Jujuy, Salta, Chaco e Formosa e do Paraguay. Sibynomorphus lavillai sp. nov. é caracterizado pela presença de manchas sobre todo o corpo que alcançam a primeira fileira de escamas; estas manchas säo mais largas ou iguais ao inter-espaço anteriormente e mais estreitas posteriormente; pela fileira vertebral moderadamente alargada; pelo processo palatino estendendo-se até a extremidade anterior do maxilar e por ter de 47 a 61 subcaudais