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El fenómeno de Raynaud consiste en la contracción excesiva de los vasos sanguíneos en respuesta a diversos estímulos y, si bien suele comprometer las extremidades, existen otras localizaciones menos frecuentemente afectadas. Este trabajo se enfoca en describir las características de una serie de mujeres con fenómeno de Raynaud en el pezón. Mediante revisión de historias clínicas y comunicación directa con las pacientes, se recopilaron y analizaron los datos de 12 mujeres con Raynaud del pezón entre 2016 y 2023. Se evaluaron variables como edad, síntomas, desencadenantes, tratamientos y duración de los síntomas. En esta serie de casos, el fenómeno de Raynaud del pezón en mujeres lactantes se manifestó con mayor frecuencia en primigestas alrededor del décimo día posparto; el dolor fue intenso, en la mayoría mejoró con tratamientos locales y/o farmacológicos, y no limitó la duración de la lactancia materna.

Raynaud's phenomenon consists of excessive contraction of the blood vessels in response to various stimuli; although it usually affects the extremities, other locations are less frequently involved. This study focused on describing the characteristics of a series of women with Raynaud's phenomenon of the nipple. Through medical record review and direct communication with patients, data from 12 women diagnosed with Raynaud's phenomenon of the nipple between 2016 and 2023 were collected and analyzed. The following variables were assessed: age, symptoms, triggering factors, treatment, and duration of symptoms. In this case series, Raynaud's phenomenon of the nipple in breastfeeding women was more common among primiparous women around 10 days after delivery; pain was severe and, in most cases, improved with local and/or drug treatment, and did not limit the duration of breastfeeding.

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Despite the increasing knowledge in the past years, only minimal attention has been directed to the neuropsychological aspects and the prevalence of cognitive impairment associated with reversible cerebral vasoconstriction syndrome (RCVS). Objective: To describe the frequency and expand the understanding of cognitive dysfunction in RCVS. Methods: The neuropsychological evaluation was performed using a battery consisting of specific neuropsychological instruments that were administered to patients diagnosed with RCVS. A triage was conducted to exclude other potential causes of cognitive impairment. Performance on the tests was treated as a categorical variable, and a cutoff of -1.5 Z-score was adopted to indicate impaired performance. Results: Seven patients diagnosed with RCVS were evaluated, all of whom had a bachelor's degree and normal score in the Mini-Mental State Examination. The average time between diagnosis and neuropsychological evaluation was 1.8 years. Among the patients, 85.6% (n=6) exhibited performance below that of the normal population in at least two of the administered tests. Specifically, 71.4% (n=5) showed alterations in tests from the Psychological Battery for Attention Assessment, with impairment observed in concentrated (n=1), divided (n=3), or alternating (n=4) attention. Furthermore, 28.6% (n=2) demonstrated impairments in the Phonological Verbal Fluency Task, another 28.6% (n=2) exhibited difficulties copying elements of the Rey Complex Figure, and 14.3% (n=1) displayed lower performance in the Five-Digit test, all indicating executive dysfunction. Conclusion: This study provides evidence that cognitive impairment associated with RCVS is more prevalent than previously believed and has not received sufficient attention. Specifically, attention and executive functions are the cognitive domains most significantly impacted by RCVS.

Apesar do crescente conhecimento nos últimos anos, pouca atenção tem sido direcionada aos aspectos neuropsicológicos e à prevalência de declínio cognitivo associado à Síndrome de Vasoconstrição Cerebral Reversível (SVCR). Objetivo: Descrever a frequência e expandir o entendimento da disfunção cognitiva associada à SVCR. Métodos: A avaliação neuropsicológica foi realizada por meio de uma bateria composta de instrumentos neuropsicológicos específicos, que foram aplicados aos pacientes com SVCR. Uma triagem foi realizada para excluir outras potenciais causas de declínio cognitivo. O desempenho nos testes foi considerado como variável categórica, e o corte de −1,5 escore z foi adotado para indicar desempenho comprometido. Resultados: Sete pacientes com diagnóstico de SVCR foram avaliados, os quais tinham todos nível de ensino superior e pontuação normal no Miniexame do Estado Mental. A média de tempo entre o diagnóstico e a avaliação neuropsicológica foi de 1,8 ano. Dentre os pacientes, 85,6%(n=6) apresentaram desempenho comprometido em pelo menos dois dos testes aplicados. Especificamente, 71,4% (n=5) apresentaram alterações nos testes da Bateria Psicológica para Avaliação da Atenção, com comprometimento observado nas atenções concentrada (n=1), dividida (n=3), ou alternada (n=4). Além disso, 28,6% (n=2) demonstraram comprometimento na Fluência Verbal Fonológica, 28,6% (n=2) exibiram dificuldades na cópia da Figura Complexa de Rey e um paciente obteve desempenho alterado no Teste dos Cinco Dígitos, todos indicando disfunção executiva. Conclusão: Este estudo fornece evidência de que o declínio cognitivo associado à SVCR é mais prevalente do que se acreditava anteriormente. Especialmente, os domínios mais significativamente comprometidos foram a atenção e as funções executivas.

RESUMO

Raynaud's phenomenon consists of excessive contraction of the blood vessels in response to various stimuli; although it usually affects the extremities, other locations are less frequently involved. This study focused on describing the characteristics of a series of women with Raynaud's phenomenon of the nipple. Through medical record review and direct communication with patients, data from 12 women diagnosed with Raynaud's phenomenon of the nipple between 2016 and 2023 were collected and analyzed. The following variables were assessed: age, symptoms, triggering factors, treatment, and duration of symptoms. In this case series, Raynaud's phenomenon of the nipple in breastfeeding women was more common among primiparous women around 10 days after delivery; pain was severe and, in most cases, improved with local and/or drug treatment, and did not limit the duration of breastfeeding.

El fenómeno de Raynaud consiste en la contracción excesiva de los vasos sanguíneos en respuesta a diversos estímulos y, si bien suele comprometer las extremidades, existen otras localizaciones menos frecuentemente afectadas. Este trabajo se enfoca en describir las características de una serie de mujeres con fenómeno de Raynaud en el pezón. Mediante revisión de historias clínicas y comunicación directa con las pacientes, se recopilaron y analizaron los datos de 12 mujeres con Raynaud del pezón entre 2016 y 2023. Se evaluaron variables como edad, síntomas, desencadenantes, tratamientos y duración de los síntomas. En esta serie de casos, el fenómeno de Raynaud del pezón en mujeres lactantes se manifestó con mayor frecuencia en primigestas alrededor del décimo día posparto; el dolor fue intenso, en la mayoría mejoró con tratamientos locales y/o farmacológicos, y no limitó la duración de la lactancia materna.

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When an organism detects decreases in their core body temperature, the hypothalamus, the main thermoregulatory center, triggers compensatory responses. These responses include vasomotor changes to prevent heat loss and physiological mechanisms (e.g., shivering and non-shivering thermogenesis) for heat production. Both types of changes require the participation of peripheral thermoreceptors, afferent signaling to the spinal cord and hypothalamus, and efferent pathways to motor and/or sympathetic neurons. The present review aims to analyze the scientific evidence of the hypothalamic control of hypothermia and the central and peripheral changes that are triggered in domestic animals.

RESUMO

Arthritis has important cardiovascular repercussions. Phenylephrine-induced vasoconstriction is impaired in rat aortas in the early phase of the adjuvant-induced arthritis (AIA), around the 15th day post-induction. Therefore, the present study aimed to verify the effects of AIA on hyporesponsiveness to phenylephrine in rat aortas. AIA was induced by intradermal injection of Mycobacterium tuberculosis (3.8 mg/dL) in the right hind paw of male Wistar rats (n=27). Functional experiments in isolated aortas were carried out 15 days after AIA induction. Morphometric and stereological analyses of the aortas were also performed 36 days after the induction of AIA. AIA did not promote structural modifications in the aortas at any of the time points studied. AIA reduced phenylephrine-induced contraction in endothelium-intact aortas, but not in endothelium-denuded aortas. However, AIA did not change KCl-induced contraction in either endothelium-intact or denuded aortas. L-NAME (non-selective NOS inhibitor), 1400W (selective iNOS inhibitor), and ODQ (guanylyl cyclase inhibitor) reversed AIA-induced hyporesponsiveness to phenylephrine in intact aortas. 7-NI (selective nNOS inhibitor) increased the contraction induced by phenylephrine in aortas from AIA rats. In summary, the hyporesponsiveness to phenylephrine induced by AIA was endothelium-dependent and mediated by iNOS-derived NO through activation of the NO-guanylyl cyclase pathway.

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Hydrogen sulfide (H2S) is a gasotransmitter implied in metabolic diseases, insulin resistance, obesity, and type 2 Diabetes Mellitus. This study aimed to determine the effect of chronic administration of sodium hydrosulfide (NaHS; inorganic H2S donor), L-Cysteine (L-Cys; substrate of H2S producing enzymes) and DL-Propargylglycine (DL-PAG; cystathionine-gamma-lyase inhibitor) on the vascular dysfunction induced by insulin resistance in rat thoracic aorta. For this purpose, 72 animals were divided into two main sets that received: 1) tap water (control group; n = 12); and 2) fructose 15% w/v in drinking water [insulin resistance group (IR); n = 60] for 20 weeks. After 16 weeks, the group 2 was divided into five subgroups (n = 12 each), which received daily i. p. injections during 4 weeks of: 1) non-treatment (control); 2) vehicle (phosphate buffer saline; PBS, 1 ml/kg); 3) NaHS (5.6 mg/kg); 4) L-Cys (300 mg/kg); and (5) DL-PAG (10 mg/kg). Hemodynamic variables, metabolic variables, vascular function, ROS levels and the expression of p-eNOS and eNOS were determined. IR induced: 1) hyperinsulinemia; 2) increased HOMA-index; 3) decreased Matsuda index; 4) hypertension, vascular dysfunction, increased ROS levels; 5) increased iNOS, and 6) decreased CSE, p-eNOS and eNOS expression. Furthermore, IR did not affect contractile responses to norepinephrine. Interestingly, NaHS and L-Cys treatment, reversed IR-induced impairments and DL-PAG treatment decreased and increased the HOMA and Matsuda index, respectively. Taken together, these results suggest that NaHS and L-Cys decrease the metabolic and vascular alterations induced by insulin resistance by reducing oxidative stress and activating eNOS. Thus, hydrogen sulfide may have a therapeutic application.

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ABSTRACT. Despite the increasing knowledge in the past years, only minimal attention has been directed to the neuropsychological aspects and the prevalence of cognitive impairment associated with reversible cerebral vasoconstriction syndrome (RCVS). Objective: To describe the frequency and expand the understanding of cognitive dysfunction in RCVS. Methods: The neuropsychological evaluation was performed using a battery consisting of specific neuropsychological instruments that were administered to patients diagnosed with RCVS. A triage was conducted to exclude other potential causes of cognitive impairment. Performance on the tests was treated as a categorical variable, and a cutoff of −1.5 Z-score was adopted to indicate impaired performance. Results: Seven patients diagnosed with RCVS were evaluated, all of whom had a bachelor's degree and normal score in the Mini-Mental State Examination. The average time between diagnosis and neuropsychological evaluation was 1.8 years. Among the patients, 85.6% (n=6) exhibited performance below that of the normal population in at least two of the administered tests. Specifically, 71.4% (n=5) showed alterations in tests from the Psychological Battery for Attention Assessment, with impairment observed in concentrated (n=1), divided (n=3), or alternating (n=4) attention. Furthermore, 28.6% (n=2) demonstrated impairments in the Phonological Verbal Fluency Task, another 28.6% (n=2) exhibited difficulties copying elements of the Rey Complex Figure, and 14.3% (n=1) displayed lower performance in the Five-Digit test, all indicating executive dysfunction. Conclusion: This study provides evidence that cognitive impairment associated with RCVS is more prevalent than previously believed and has not received sufficient attention. Specifically, attention and executive functions are the cognitive domains most significantly impacted by RCVS.

RESUMO. Apesar do crescente conhecimento nos últimos anos, pouca atenção tem sido direcionada aos aspectos neuropsicológicos e à prevalência de declínio cognitivo associado à Síndrome de Vasoconstrição Cerebral Reversível (SVCR). Objetivo: Descrever a frequência e expandir o entendimento da disfunção cognitiva associada à SVCR. Métodos: A avaliação neuropsicológica foi realizada por meio de uma bateria composta de instrumentos neuropsicológicos específicos, que foram aplicados aos pacientes com SVCR. Uma triagem foi realizada para excluir outras potenciais causas de declínio cognitivo. O desempenho nos testes foi considerado como variável categórica, e o corte de −1,5 escore z foi adotado para indicar desempenho comprometido. Resultados: Sete pacientes com diagnóstico de SVCR foram avaliados, os quais tinham todos nível de ensino superior e pontuação normal no Miniexame do Estado Mental. A média de tempo entre o diagnóstico e a avaliação neuropsicológica foi de 1,8 ano. Dentre os pacientes, 85,6%(n=6) apresentaram desempenho comprometido em pelo menos dois dos testes aplicados. Especificamente, 71,4% (n=5) apresentaram alterações nos testes da Bateria Psicológica para Avaliação da Atenção, com comprometimento observado nas atenções concentrada (n=1), dividida (n=3), ou alternada (n=4). Além disso, 28,6% (n=2) demonstraram comprometimento na Fluência Verbal Fonológica, 28,6% (n=2) exibiram dificuldades na cópia da Figura Complexa de Rey e um paciente obteve desempenho alterado no Teste dos Cinco Dígitos, todos indicando disfunção executiva. Conclusão: Este estudo fornece evidência de que o declínio cognitivo associado à SVCR é mais prevalente do que se acreditava anteriormente. Especialmente, os domínios mais significativamente comprometidos foram a atenção e as funções executivas.

RESUMO

Purpose: To evaluate whether a subtraction CT angiography (sCTA) perfusion score may have prognostic value in patients with COVID-19 pneumonia. Method: This prospective cohort study included adult patients with RT-PCR-confirmed SARS-CoV-2 infection admitted to the ED and a sCTA performed within 24 h of admission between June and September 2020. Perfusion abnormalities (PA) in areas of apparently spared lung parenchyma on conventional CT images were assessed with sCTA perfusion score. Airspace disease extension was assessed with CT severity scores, which were then correlated with clinical outcomes (admission to ICU, requirement of IMV, and death). Inter-rater reliability (IRR) was assessed using Cohen's Kappa. Independent predictors of adverse outcomes were evaluated by multivariable logistic regression analyses using the Hosmer and Lemeshow's test. Results: 191 patients were included: 112 males (58%), median age of 60.8 years (SD ± 16.0). The IRR was very high (median Kappa statistic: 0.95). No association was found between perfusion CT scores and D-dimer levels (Kendall's Tau-B coefficient = 0.08, p = 0.16) or between PaO2/FiO2 ratios and D-dimer levels (Kendall's Tau-B coefficient = -0.10, p = 0.07). Multivariate analyses adjusting for parenchymal disease extension, vascular beaded appearance, pulmonary embolism, sex, and age showed that severe PA remained a significant predictor for ICU admission (AOR: 6.25, 95% CI 2.10-18.7, p = 0.001). The overall diagnostic capacity of this model was adequate (ROC AUC: 0.83; 95% CI 0.77-0.89). Conclusions: The assessment of pulmonary perfusion abnormalities in areas of apparently spared lung parenchyma on conventional CT images via sCTA perfusion scoring has prognostic value in COVID-19 pneumonia.

RESUMO

Electroporation has emerged as a suitable technique to induce the pore formation in the cell membrane of cancer tissues, facilitating the cellular internalization of chemotherapeutic drugs. An adequate selection of the electric pulse characteristics is crucial to guarantee the efficiency of this technique, minimizing the adverse effects. In the present work, the dual reciprocity boundary element method (DR-BEM) is applied for the simulation of drug transport in the extracellular and intracellular space of cancer tissues subjected to the application of controlled electric pulses, using a continuum tumour cord approach, and considering both the electro-permeabilization and vasoconstriction phenomena. The developed DR-BEM algorithm is validated with numerical and experimental results previously published, obtaining a satisfactory accuracy and convergence. Using the DR-BEM code, a study about the influence of the magnitude of electric field (E) and pulse spacing (dpulses) on the time behavior and spatial distribution of the internalized drug, as well as on the cell survival fraction, is carried out. In general, the change of drug concentration, drug exposure and cell survival fraction with the parameters E and dpulses is ruled by two important factors: the balance between the electro-permeabilization and vasoconstriction phenomena, and the relative importance of the sources of cell death (electric pulses and drug cytotoxicity); these two factors, in turn, significantly depend on the reversible and irreversible thresholds considered for the electric field.

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El síndrome de vasoconstricción cerebral reversible es poco frecuente y su fisiopatología aún no está bien dilucidada. Su presentación clínica se caracteriza por manifestaciones neurológicas como cefalea "en trueno", déficit focal, vómito, fotofobia y, en casos graves, puede tener complicaciones como eventos cerebrovasculares isquémicos o hemorrágicos. El diagnóstico se realiza mediante angiografía cerebral, angiotomografía o angioresonancia, las cuales documentan vasoconstricción de las arterias cerebrales con resolución espontánea, que en la mayoría de los casos es consistente con un buen pronóstico clínico. A continuación, se expone el caso de una paciente con vasoconstricción cerebral reversible y lesión miocárdica asociada, en donde se logra un diagnóstico mediante imágenes y tratamiento oportuno. La importancia del caso radica en informar sobre el reconocimiento temprano de una complicación miocárdica poco común del síndrome de vasoconstricción cerebral, pero con riesgo de morbimortalidad dentro del espectro de los cuadros cerebrovasculares.

Reversible Cerebral Vasoconstriction Syndrome is a rare condition, and its pathophysiology is not yet fully understood. Its clinical presentation is characterized by neurological manifestations such as "thunderclap" headache, focal deficit, vomiting, photophobia, and, in severe cases, it can lead to complications such as ischemic or hemorrhagic cerebrovascular events. The diagnosis is made through cerebral angiography, CT angiography, or magnetic resonance angiography, which demonstrate vasoconstriction of the cerebral arteries with spontaneous resolution, which in most cases is consistent with a good clinical prognosis. Here, we present the case of a patient with reversible cerebral vasoconstriction syndrome and associated myocardial injury, where a diagnosis was achieved through imaging and timely treatment. The importance of this case lies in raising awareness about the early recognition of a rare myocardial complication of reversible cerebral vasoconstriction syndrome, which carries a risk of morbidity and mortality within the spectrum of cerebrovascular disorders.

A síndrome de vasoconstrição cerebral reversível é rara e sua fisiopatologia ainda não é bem compreendida. Sua apresentação clínica é caracterizada por manifestações neuro-lógicas como cefaléia em trovoada, déficit focal, vômitos, fotofobia e, em casos graves, pode ter complicações como eventos cerebrovasculares isquêmicos ou hemorrágicos. O diagnóstico é feito por angiografia cerebral, angiotomografia ou angiorressonância , que documentam vasoconstrição das artérias cerebrais com resolução espontânea, o que na maioria dos casos é compatível com bom prognóstico clínico. A seguir, é apresentado o caso de um paciente com vasoconstrição cerebral reversível e lesão miocárdica associa-da, onde o diagnóstico é feito por imagem e tratamento oportuno. A importância do caso está em relatar o reconhecimento precoce de uma rara complicação miocárdica da síndrome de vasoconstrição cerebral, mas com risco de morbimortalidade dentro do espectro das doenças cerebrovasculares.

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Hypobaric hypoxia under chromic conditions triggers hypoxic pulmonary vasoconstriction (HPV) and right ventricular hypertrophy (RVH). The role of zinc (Zn) under hypoxia is controversial and remains unclear. We evaluated the effect of Zn supplementation in prolonged hypobaric hypoxia on HIF2α/MTF-1/MT/ZIP12/PKCε pathway in the lung and RVH. Wistar rats were exposed to hypobaric hypoxia for 30 days and randomly allocated into three groups: chronic hypoxia (CH); intermittent hypoxia (2 days hypoxia/2 days normoxia; CIH); and normoxia (sea level control; NX). Each group was subdivided (n = 8) to receive either 1% Zn sulfate solution (z) or saline (s) intraperitoneally. Body weight, hemoglobin, and RVH were measured. Zn levels were evaluated in plasma and lung tissue. Additionally, the lipid peroxidation levels, HIF2α/MTF-1/MT/ZIP12/PKCε protein expression and pulmonary artery remodeling were measured in the lung. The CIH and CH groups showed decreased plasma Zn and body weight and increased hemoglobin, RVH, and vascular remodeling; the CH group also showed increased lipid peroxidation. Zn administration under hypobaric hypoxia upregulated the HIF2α/MTF-1/MT/ZIP12/PKCε pathway and increased RVH in the intermittent zinc group. Under intermittent hypobaric hypoxia, Zn dysregulation could participate in RVH development through alterations in the pulmonary HIF2α/MTF1/MT/ZIP12/PKCε pathway.

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La hipertensión arterial pulmonar se caracteriza por una presión arterial pulmonar media y resistencia vascular pulmonar elevadas y remodelado patológico de las arterias pulmonares. La entrada de calcio desde el espacio extracelular al intracelular a través de canales dependientes e independientes de voltaje juega un rol fundamental en el aumento de la contractilidad de las arterias pulmonares y la pérdida de regulación del comportamiento proliferativo de las células de las distintas capas de la pared de las arterias pulmonares. De esta manera, estos canales contribuyen con la vasoconstricción exacerbada de las arterias pulmonares y a su remodelado patológico. El objetivo de esta revisión es recapitular la evidencia obtenida desde modelos celulares y animales respecto a la contribución de los principales canales de calcio de membrana plasmática en estos mecanismos fisiopatológicos claves en el desarrollo de la hipertensión pulmonar, discutiendo su valor potencial como diana farmacológica para terapias presentes y futuras.

Pulmonary arterial hypertension is characterized by increased mean pulmonary arterial pressure, resistance, and pathological remodeling of pulmonary arteries. Calcium entry from the extracellular to the intracellular space through voltage-dependent and -independent channels play a major role in the increase of contractility of pulmonary arteries and in the loss of regulation of the proliferative behavior of the cells from the different layers of the pulmonary arterial wall. In doing so, these channels contribute to enhanced vasoconstriction of pulmonary arteries and their pathological remodeling. This review aims to summarize the evidence obtained from animal and cellular models regarding the involvement of the main plasma membrane calcium channels in these key pathophysiological processes for pulmonary arterial hypertension, discussing the potential value as pharmacological targets for therapies in the present and the future.

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Reversible cerebral vasoconstriction syndrome (RCVS) is a clinical condition characterized by arterial involvement of the intracranial vessels, manifesting with vasospasm. The most common clinical manifestation related to the syndrome is the thunderclap headache, which consists of a severe headache that reaches the peak of pain within minutes. The imaging study assumes a leading role in the complementary investigation. Laboratory tests and cerebrospinal fluid analysis are often nonspecific and without significant diagnostic importance. Non-contrast studies of the brain parenchyma reveal variable results that can often be normal. Angiographic findings, which initially may not reveal any changes, allow the visualization of diffuse narrowing of the vessels, with the posterior cerebral circulation being preferentially affected. The present study reports the case of a 19-year-old woman with no relevant medical history, except that she was a regular user of marijuana and a drug based on chloroform and ether. The patient showed clinical and imaging signs compatible with RCVS, and the narcotics used by her were considered precipitating factors.

RESUMO

Hypobaric hypoxia is a condition that occurs at high altitudes (>2500 m) where the partial pressure of gases, particularly oxygen (PO2), decreases. This condition triggers several physiological and molecular responses. One of the principal responses is pulmonary vascular contraction, which seeks to optimize gas exchange under this condition, known as hypoxic pulmonary vasoconstriction (HPV); however, when this physiological response is exacerbated, it contributes to the development of high-altitude pulmonary hypertension (HAPH). Increased levels of zinc (Zn2+) and oxidative stress (known as the "ROS hypothesis") have been demonstrated in the vasoconstriction process. Therefore, the aim of this review is to determine the relationship between molecular pathways associated with altered Zn2+ levels and oxidative stress in HPV in hypobaric hypoxic conditions. The results indicate an increased level of Zn2+, which is related to increasing mitochondrial ROS (mtROS), alterations in nitric oxide (NO), metallothionein (MT), zinc-regulated, iron-regulated transporter-like protein (ZIP), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-induced protein kinase C epsilon (PKCε) activation in the development of HPV. In conclusion, there is an association between elevated Zn2+ levels and oxidative stress in HPV under different models of hypoxia, which contribute to understanding the molecular mechanism involved in HPV to prevent the development of HAPH.

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Thermoregulation in newborn mammals is an essential species-specific mechanism of the nervous system that contributes to their survival during the first hours and days of their life. When exposed to cold weather, which is a risk factor associated with mortality in neonates, pathways such as the hypothalamic-pituitary-adrenal axis (HPA) are activated to achieve temperature control, increasing the circulating levels of catecholamine and cortisol. Consequently, alterations in blood circulation and mechanisms to produce or to retain heat (e.g., vasoconstriction, piloerection, shivering, brown adipocyte tissue activation, and huddling) begin to prevent hypothermia. This study aimed to discuss the mechanisms of thermoregulation in newborn domestic mammals, highlighting the differences between altricial and precocial species. The processes that employ brown adipocyte tissue, shivering, thermoregulatory behaviors, and dermal vasomotor control will be analyzed to understand the physiology and the importance of implementing techniques to promote thermoregulation and survival in the critical post-birth period of mammals. Also, infrared thermography as a helpful method to perform thermal measurements without animal interactions does not affect these parameters.

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ABSTRACT Purpose: To examine changes in the eyes after cold compress application at the early stage. Method: A total of 62 eyes from 62 healthy adult participants were included in this cross-sectional and comparative study. The subfoveal choroidal thickness and retinal nerve fiber thickness were measured by spectral-domain ocular coherence tomography. The central corneal thickness, anterior segment volume and depth, iridocorneal angle, and pupil diameter were measured by means of the Scheimpflug anterior segment imaging method. The measurements were repeated after 10 min of cold compress application, which was applied using special packs. The procedures were then repeated with non-cold packages to exclude the effect of pressure. Results: The average age of the participants was 30.74 ± 5.82 years. There was no significant change in the central corneal thickness after cold compress application, and there was a significant decrease in the anterior segment volume (p<0.001), anterior segment depth (p<0.001), and pupil diameter. Moreover, the iridocorneal angle increased (p=0.002). The subfoveal choroidal thickness decreased after the application of cold compress (p<0.001). The overall disk thickness (p=0.034) and superior nasal scale (p=0.007) significantly decreased after the cold compress was administered during the evaluation of optic nerve fiber thickness. In contrast to that with the cold application, the subfoveal choroidal thickness and optic nerve fiber thickness did not change after the non-cold compress application (p>0.05). Conclusion: Cold compress application may thus cause some physiological changes in the eyes, which necessitates the examination of its usage and effects.

RESUMO Objetivos: Examinar as mudanças nos olhos após a aplicação com compressa fria. Método: Sessenta e dois olhos de 62 adultos saudáveis foram incluídos neste estudo transversal e comparativo. A espessura da coróide subfoveal e a espessura da fibra nervosa retiniana foram mensuradas por tomografia de coerência óptica de domínio espectral (OCT). A espessura central da córnea, o volume e a profundidade do segmento anterior, o ângulo iridocorneano e o diâmetro da pupila foram mensurados por meio do método de imagem do segmento anterior de Scheimpflug. As medições foram repetidas após 10 minutos de aplicação de compressas frias, aplicadas com embalagens especiais. Os procedimentos foram repetidos com embalagens não frias para excluir o efeito da pressão. Resultados: A média de idade dos participantes foi de 30,74 ± 5,82 anos. Embora não tenha havido alteração significativa na espessura central da córnea após a aplicação da compressa fria, houve diminuição significativa no volume do segmento anterior (p<0,001), na profundidade do segmento anterior (p<0,001) e no diâmetro da pupila. Além disso, o ângulo iridocorneano aumentou (p=0,002). A espessura da coróide subfoveal diminuiu após a aplicação da compressa fria (p<0,001). A espessura total do disco (p=0,034) e a escala nasal superior (p=0,007) diminuíram significativamente após a administração da compressa fria durante a avaliação da espessura da fibra do nervo óptico. Ao contrário da aplicação com compressa fria, a espessura da coróide subfoveal e a espessura da fibra do nervo óptico não mudaram após a aplicação da compressa não fria (p>0,05). Conclusão: A aplicação de compressa fria pode causar algumas alterações fisiológicas nos olhos e o seu uso e efeitos devem ser observados.

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Pulmonary hypertension is an enigmatic, deleterious disease driven by multiple heterogeneous causes with a burgeoning proportion of older patients with complex, chronic comorbidities without adequate treatment options. The underlying endothelial pathophenotypes that direct vasoconstriction and panvascular remodeling remain both controversial and incompletely defined. This review discusses emerging concepts centered on endothelial senescence in pulmonary vascular disease. This principle proposes a more heterogeneous, dynamic pulmonary endothelium in disease; it provides a potentially unifying feature of endothelial dysfunction in pulmonary hypertension irrespective of cause; and it supports a clinically relevant link between aging and pulmonary hypertension like other chronic illnesses. Thus, taking cues from studies on aging and age-related diseases, we present possible opportunities and barriers to diagnostic and therapeutic targeting of senescence in pulmonary hypertension.

Assuntos

RESUMO

The authors previously demonstrated that newborn llama (NBLL) express high levels of α1 adrenergic receptors, which provide a potent vasoconstriction response when compared with newborn sheep (NBSH) gestated at sea level. However, data regarding the impact of chronic gestational hypobaric hypoxia on α-adrenergic vasoconstriction in the neonatal life has not been studied. We evaluated if gestation under chronic hypobaric hypoxia modifies α1-adrenergic vasoconstrictor function in NBLL and NBSH. We compared the vasoconstrictor response induced by potassium and α-adrenergic stimuli in isolated small femoral arteries of NBLL and NBSH gestated at high altitude (HA; 3,600 m) or low altitude (LA; 580 m). The maximal contraction (R MAX) and potency (EC50) to potassium, noradrenaline (NA), and phenylephrine (PHE) were larger in HA-NBLL than LA-NBLL. R MAX to potassium, NA, and PHE were lower in HA-NBSH when compared with LA-NBSH and potency results were similar. Competitive blockade with prazosin showed that RNLL LA/HA have a similar pA2. In contrast, NBSH had increased pA2 values in HA when compared with LA. Finally, small femoral arteries denudated or treated with LNAME in LA and HA lacked NO or endothelium participation in response to PHE stimulation. In contrast, NBSH displayed that denudation or blockade with LNAME support NO or endothelium participation in response to PHE activation. In conclusion, HA chronic hypoxia enhances α1 adrenergic receptor activity in small femoral arteries in NBLL to a higher degree than NBSH, implying a higher vasoconstriction function.

RESUMO

The reversible cerebral vasoconstriction syndrome is a variable, segmental, and multifocal constriction of brain arteries, usually with a benign course. We describe the case of a 49-year-old woman who presented with headaches, visual symptoms, and seizures. Three days after admission, vasoconstriction areas were found in at least two vascular territories in two segments of the same arteries. The patient was admitted to the intensive care unit where her blood pressure was monitored and she received medical treatment. Surprisingly, the patient presented an unpredicted evolution in developing malignant cerebral edema on the seventh day after admission. She then suffered brain death and was taken to organ donation. A guided nervous system necropsy was later performed. The pathology discarded vasculitis and exhibited hemorrhage areas in the cerebral convexity. Herein, we discuss the most relevant aspects of cases with fulminant evolution reported in the literature. The reversible cerebral vasoconstriction syndrome is usually associated with fatal outcomes when patients exhibit focalization, their first neuroimaging typically shows disturbances, and a rapid clinical deterioration occurs. It is crucial to identify factors linked to poor prognosis and set intervention strategies and early prevention.

El síndrome de vasoconstricción cerebral reversible se produce por la constricción variable, segmentaria y multifocal, de las arterias cerebrales y, generalmente, es de curso benigno. Se describe el caso de una mujer de 49 años que consultó por cefalea, síntomas visuales y convulsiones; tres días después, presentaba áreas de vasoconstricción en, por lo menos, dos territorios vasculares y dos segmentos de las mismas arterias. Fue internada en la unidad de cuidados intensivos para controlarle la presión arterial y recibir tratamiento médico. Tuvo una evolución tórpida y, en el séptimo día de hospitalización, desarrolló edema cerebral maligno, tras lo cual ocurrió la muerte cerebral. Se inició entonces el plan de donación de órganos y, posteriormente, se practicó una autopsia guiada del cerebro. El estudio de patología descartó vasculitis y reveló áreas de hemorragia en la convexidad cerebral. Se discuten los aspectos más relevantes de los casos con evolución fulminante informados en la literatura científica. El síndrome de vasoconstricción cerebral reversible se asocia con resultados fatales cuando los pacientes tienen una deficiencia neurológica focal, la neuroimagen inicial muestra alteraciones y hay un deterioro clínico rápido. Es importante conocer los factores asociados con un mal pronóstico, y establecer estrategias tempranas de intervención y prevención.

Assuntos

RESUMO

Resumen | El síndrome de vasoconstricción cerebral reversible se produce por la constricción variable, segmentaria y multifocal, de las arterias cerebrales y, generalmente, es de curso benigno. Se describe el caso de una mujer de 49 años que consultó por cefalea, síntomas visuales y convulsiones; tres días después, presentaba áreas de vasoconstricción en, por lo menos, dos territorios vasculares y dos segmentos de las mismas arterias. Fue internada en la unidad de cuidados intensivos para controlarle la presión arterial y recibir tratamiento médico. Tuvo una evolución tórpida y, en el séptimo día de hospitalización, desarrolló edema cerebral maligno, tras lo cual ocurrió la muerte cerebral. Se inició entonces el plan de donación de órganos y, posteriormente, se practicó una autopsia guiada del cerebro. El estudio de patología descartó vasculitis y reveló áreas de hemorragia en la convexidad cerebral. Se discuten los aspectos más relevantes de los casos con evolución fulminante informados en la literatura científica. El síndrome de vasoconstricción cerebral reversible se asocia con resultados fatales cuando los pacientes tienen una deficiencia neurológica focal, la neuroimagen inicial muestra alteraciones y hay un deterioro clínico rápido. Es importante conocer los factores asociados con un mal pronóstico, y establecer estrategias tempranas de intervención y prevención.

Abstract | The reversible cerebral vasoconstriction syndrome is a variable, segmental, and multifocal constriction of brain arteries, usually with a benign course. We describe the case of a 49-year-old woman who presented with headaches, visual symptoms, and seizures. Three days after admission, vasoconstriction areas were found in at least two vascular territories in two segments of the same arteries. The patient was admitted to the intensive care unit where her blood pressure was monitored and she received medical treatment. Surprisingly, the patient presented an unpredicted evolution in developing malignant cerebral edema on the seventh day after admission. She then suffered brain death and was taken to organ donation. A guided nervous system necropsy was later performed. The pathology discarded vasculitis and exhibited hemorrhage areas in the cerebral convexity. Herein, we discuss the most relevant aspects of cases with fulminant evolution reported in the literature. The reversible cerebral vasoconstriction syndrome is usually associated with fatal outcomes when patients exhibit focalization, their first neuroimaging typically shows disturbances, and a rapid clinical deterioration occurs. It is crucial to identify factors linked to poor prognosis and set intervention strategies and early prevention.

Assuntos