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1.
J Med Case Rep ; 18(1): 24, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38243328

RESUMO

BACKGROUND: Carcinosarcoma of the parotid gland is an extremely rare malignancy comprising of 0.04-0.16% of all salivary gland tumors. This is the first case of an adenoid cystic carcinoma with chondrosarcoma to the best of our knowledge. They consist of distinct carcinomatous and sarcomatous components and may arise de novo or from a preexisting pleomorphic adenoma. CASE PRESENTATION: Herein we present a case of an 80-year-old white female who presented with progressively increasing left facial swelling over 6 weeks. Magnetic Resonance Imagining revealed a mass (3.4 cm) in the parotid gland with a predominant cystic/necrotic component. The cytology was atypical (Milan3) and a total parotidectomy and selective lymph node dissection was done. The resection showed extensive necrosis with high grade sarcomatous (chondrosarcoma) areas. The epithelial component was adenoid cystic carcinoma with perineural invasion. The patient is currently undergoing radiotherapy of the tumor bed and skull base due to propensity of perineural invasion of the adenoid cystic component. The most common carcinomas in carcinosarcomas of salivary glands are adenocarcinoma and squamous cell carcinoma. CONCLUSION: Carcinosarcoma is a high-grade aggressive lesion with a poor prognosis and should be treated aggressively. More studies are needed to understand the origin of these tumors.


Assuntos
Neoplasias Ósseas , Carcinoma Adenoide Cístico , Carcinossarcoma , Condrossarcoma , Neoplasias Parotídeas , Humanos , Feminino , Idoso de 80 Anos ou mais , Glândula Parótida/patologia , Neoplasias Parotídeas/diagnóstico por imagem , Neoplasias Parotídeas/cirurgia , Carcinoma Adenoide Cístico/diagnóstico por imagem , Carcinoma Adenoide Cístico/cirurgia , Carcinoma Adenoide Cístico/patologia , Carcinossarcoma/diagnóstico , Carcinossarcoma/cirurgia , Carcinossarcoma/patologia , Condrossarcoma/patologia , Neoplasias Ósseas/patologia
2.
OTO Open ; 8(1): e105, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38259521

RESUMO

Objective: To review new drugs and devices relevant to otolaryngology approved by the Food and Drug Administration (FDA) in 2022. Data Sources: Publicly available FDA data on drugs and devices approved in 2022. Review Methods: A preliminary screen was conducted to identify drugs and devices relevant to otolaryngology. A secondary screen by members of the American Academy of Otolaryngology-Head and Neck Surgery's (AAO-HNS) Medical Devices and Drugs Committee differentiated between minor updates and new approvals. The final list of drugs and devices was sent to members of each subspecialty for review and analysis. Conclusion: A total of 1251 devices and 37 drugs were identified on preliminary screening. Of these, 329 devices and 5 drugs were sent to subspecialists for further review, from which 37 devices and 2 novel drugs were selected for further analysis. The newly approved devices spanned all subspecialties within otolaryngology. Many of the newly approved devices aimed to enhance patient experience, including over-the-counter hearing aids, sleep monitoring devices, and refined CPAP devices. Other advances aimed to improve surgical access, convenience, or comfort in the operating room and clinic. Implications for Practice: Many new devices and drugs are approved each year to improve patient care and care delivery. By staying up to date with these advances, otolaryngologists can leverage new innovations to improve the safety and quality of care. Given the recent approval of these devices, further studies are needed to assess long-term impact within the field of otolaryngology.

3.
BMJ Neurol Open ; 5(1): e000343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37265548

RESUMO

Objectives: This study aims to describe which concussion subtype(s) result specifically from the explosions of theatre ballistic missiles (TBMs) blast waves, an extremely rare occurrence in modern warfare. We provide feedback from using the US military's standard acute concussion screening tool, the Military Acute Concussion Examination version 2, in a deployed, chaotic, real-world environment. Background: Iran launched 27 professionally manufactured TBMs into Iraq on 8 January 2020. Eleven detonated within Al Asad Air Base, exposing approximately 330 soldiers to TBM-blast waves. The concussion subtype(s) resultant from TBM blast-related concussion is not known. Methods: Case series from the Al Asad TBM-blast exposed cohort who evacuated to Landstuhl Regional Medical Center (LRMC), Germany up to 3 months following the attack and were diagnosed with concussion. Around 4 weeks, TBM-blast exposed individuals still present on Al Asad were screened with the Neurobehavioural Symptom Inventory (NSI) and vestibular ocular motor screening (VOMS); positive screens evacuated to LRMC. Data from 8 January 2020 to 7 April 2020 were cross-sectionally analysed. Results: 35/38 patients met criteria for mild traumatic brain injury/concussion. 34/35 were within a 100 m blast radius. Migraine/headache, cognitive and mood/anxiety subtypes were common. VOMS was abnormal in 18/18 tested; 16 deferred due to overt symptoms. The 4-week screen identified nine additional concussed individuals. Conclusions: Among TBM-blast concussion patients, migraine/headache, cognitive, mood/anxiety and likely vestibular/ocular motor subtypes were predominant. Our study supports postconcussion screening that includes both a subjective symptom inventory, for example, NSI, and a performance-based ocular motor/vestibular screening examination, for example, VOMS, to help identify patients who may under recognise or under-report/minimise symptoms.

4.
Nanomaterials (Basel) ; 13(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37368291

RESUMO

We characterize the effect of ferromagnetic nickel nanoparticles (size ∼6 nm) on the magnetotransport properties of chemical-vapor-deposited (CVD) graphene. The nanoparticles were formed by thermal annealing of a thin Ni film evaporated on top of a graphene ribbon. The magnetoresistance was measured while sweeping the magnetic field at different temperatures, and compared against measurements performed on pristine graphene. Our results show that, in the presence of Ni nanoparticles, the usually observed zero-field peak of resistivity produced by weak localization is widely suppressed (by a factor of ∼3), most likely due to the reduction of the dephasing time as a consequence of the increase in magnetic scattering. On the other hand, the high-field magnetoresistance is amplified by the contribution of a large effective interaction field. The results are discussed in terms of a local exchange coupling, J∼6 meV, between the graphene π electrons and the 3d magnetic moment of nickel. Interestingly, this magnetic coupling does not affect the intrinsic transport parameters of graphene, such as the mobility and transport scattering rate, which remain the same with and without Ni nanoparticles, indicating that the changes in the magnetotransport properties have a purely magnetic origin.

5.
Cardiovasc Res ; 119(8): 1751-1762, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37041718

RESUMO

AIMS: Chronic stress is a well-known risk factor for the development of hypertension. However, the underlying mechanisms remain unclear. Corticotropin-releasing hormone (CRH) neurons in the central nucleus of the amygdala (CeA) are involved in the autonomic responses to chronic stress. Here, we determined the role of CeA-CRH neurons in chronic stress-induced hypertension. METHODS AND RESULTS: Borderline hypertensive rats (BHRs) and Wistar-Kyoto (WKY) rats were subjected to chronic unpredictable stress (CUS). Firing activity and M-currents of CeA-CRH neurons were assessed, and a CRH-Cre-directed chemogenetic approach was used to suppress CeA-CRH neurons. CUS induced a sustained elevation of arterial blood pressure (ABP) and heart rate (HR) in BHRs, while in WKY rats, CUS-induced increases in ABP and HR quickly returned to baseline levels after CUS ended. CeA-CRH neurons displayed significantly higher firing activities in CUS-treated BHRs than unstressed BHRs. Selectively suppressing CeA-CRH neurons by chemogenetic approach attenuated CUS-induced hypertension and decreased elevated sympathetic outflow in CUS-treated BHRs. Also, CUS significantly decreased protein and mRNA levels of Kv7.2 and Kv7.3 channels in the CeA of BHRs. M-currents in CeA-CRH neurons were significantly decreased in CUS-treated BHRs compared with unstressed BHRs. Blocking Kv7 channel with its blocker XE-991 increased the excitability of CeA-CRH neurons in unstressed BHRs but not in CUS-treated BHRs. Microinjection of XE-991 into the CeA increased sympathetic outflow and ABP in unstressed BHRs but not in CUS-treated BHRs. CONCLUSIONS: CeA-CRH neurons are required for chronic stress-induced sustained hypertension. The hyperactivity of CeA-CRH neurons may be due to impaired Kv7 channel activity, which represents a new mechanism involved in chronic stress-induced hypertension.


Assuntos
Núcleo Central da Amígdala , Hipertensão , Ratos , Animais , Hormônio Liberador da Corticotropina/metabolismo , Núcleo Central da Amígdala/metabolismo , Ratos Endogâmicos WKY , Hipertensão/metabolismo , Neurônios/metabolismo
6.
Diagnostics (Basel) ; 13(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36832195

RESUMO

Since the beginning of the COVID-19 pandemic, there has been enormous interest in the development of measures that would allow for the swift detection of the disease. The rapid screening and preliminary diagnosis of SARS-CoV-2 infection allow for the instant identification of possibly infected individuals and the subsequent mitigation of the disease spread. Herein, the detection of SARS-CoV-2-infected individuals was explored using noninvasive sampling and low-preparatory-work analytical instrumentation. Hand odor samples were obtained from SARS-CoV-2-positive and -negative individuals. The volatile organic compounds (VOCs) were extracted from the collected hand odor samples using solid phase microextraction (SPME) and analyzed using gas chromatography coupled with mass spectrometry (GC-MS). Sparse partial least squares discriminant analysis (sPLS-DA) was used to develop predictive models using the suspected variant sample subsets. The developed sPLS-DA models performed moderately (75.8% (±0.4) accuracy, 81.8% sensitivity, 69.7% specificity) at distinguishing between SARS-CoV-2-positive and negative -individuals based on the VOC signatures alone. Potential markers for distinguishing between infection statuses were preliminarily acquired using this multivariate data analysis. This work highlights the potential of using odor signatures as a diagnostic tool and sets the groundwork for the optimization of other rapid screening sensors such as e-noses or detection canines.

7.
Hypertension ; 80(1): 1-12, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36069195

RESUMO

Hypertension affects over 1 billion individuals worldwide. Because the cause of hypertension is known only in a small fraction of patients, most individuals with high blood pressure are diagnosed as having essential hypertension. Elevated sympathetic nervous system activity has been identified in a large portion of hypertensive patients. However, the root cause for this sympathetic overdrive is unknown. A more complete understanding of the breadth of the functional capabilities of the sympathetic nervous system may lead to new insights into the cause of essential hypertension. By employing a unique experimental paradigm, we have recently discovered that the neural network controlling sympathetic drive is more reactive after rats are exposed to mild challenges (stressors) and that the hypertensive response can be sensitized (ie, hypertensive response sensitization [HTRS]). We have also found that the induction of HTRS involves plasticity in the neural network controlling sympathetic drive. The induction and maintenance of the latent HTRS state also require the functional integrity of the brain renin-angiotensin-aldosterone system and the presence of several central inflammatory factors. In this review, we will discuss the induction and expression of HTRS in adult animals and in the progeny of mothers with prenatal obesity/overnutrition or with maternal gestational hypertension. Also, interventions that reverse the effects of stressor-induced HTRS will be reviewed. Understanding the mechanisms underlying HTRS and identifying the beneficial effects of maternal or offspring early-life interventions that prevent or reverse the sensitized state can provide insights into therapeutic strategies for interrupting the vicious cycle of transgenerational hypertension.


Assuntos
Hipertensão , Mães , Animais , Ratos , Feminino , Humanos , Hipertensão Essencial
9.
Biosensors (Basel) ; 12(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36421122

RESUMO

The spread of SARS-CoV-2, which causes the disease COVID-19, is difficult to control as some positive individuals, capable of transmitting the disease, can be asymptomatic. Thus, it remains critical to generate noninvasive, inexpensive COVID-19 screening systems. Two such methods include detection canines and analytical instrumentation, both of which detect volatile organic compounds associated with SARS-CoV-2. In this study, the performance of trained detection dogs is compared to a noninvasive headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) approach to identifying COVID-19 positive individuals. Five dogs were trained to detect the odor signature associated with COVID-19. They varied in performance, with the two highest-performing dogs averaging 88% sensitivity and 95% specificity over five double-blind tests. The three lowest-performing dogs averaged 46% sensitivity and 87% specificity. The optimized linear discriminant analysis (LDA) model, developed using HS-SPME-GC-MS, displayed a 100% true positive rate and a 100% true negative rate using leave-one-out cross-validation. However, the non-optimized LDA model displayed difficulty in categorizing animal hair-contaminated samples, while animal hair did not impact the dogs' performance. In conclusion, the HS-SPME-GC-MS approach for noninvasive COVID-19 detection more accurately discriminated between COVID-19 positive and COVID-19 negative samples; however, dogs performed better than the computational model when non-ideal samples were presented.


Assuntos
COVID-19 , Odorantes , Cães , Animais , Odorantes/análise , COVID-19/diagnóstico , SARS-CoV-2 , Microextração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos
10.
Front Physiol ; 13: 1052304, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439267

RESUMO

Tumor necrosis factor (TNF)-α converting enzyme (TACE) is a key metalloprotease mediating ectodomain shedding of a variety of inflammatory mediators, substrates, and growth factors. We previously reported that TACE-mediated production of TNF-α in the hypothalamic paraventricular nucleus (PVN) contributes to sympathetic excitation in heart failure (HF). Here, we sought to determine whether central interventions in TACE activity attenuate neuroinflammation and improve cardiac function in heart failure. Myocardial infarction-induced HF or sham-operated (SHAM) rats were treated with bilateral paraventricular nucleus microinjection of a TACE siRNA or a 4-week intracerebroventricular (ICV) infusion of the TACE inhibitor TAPI-0. Compared with SHAM rats, scrambled siRNA-treated HF rats had higher TACE levels in the PVN along with increased mRNA levels of TNF-α, TNF-α receptor 1 and cyclooxygenase-2. The protein levels of TNF-α in cerebrospinal fluid and phosphorylated (p-) NF-κB p65 and extracellular signal-regulated protein kinase (ERK)1/2 in the PVN were also elevated in HF rats treated with scrambled siRNA. The expression of these inflammatory mediators and signaling molecules in the PVN of HF rats were significantly attenuated by TACE siRNA. Interestingly, the mRNA level of TNF-α receptor 2 in the PVN was increased in HF treated with TACE siRNA. Moreover, sympathetic excitation, left ventricular end-diastolic pressure, pulmonary congestion, and cardiac hypertrophy and fibrosis were reduced by PVN microinjection of TACE siRNA. A 4-week treatment with intracerebroventricular TAPI-0 had similar effects to ameliorate these variables in HF rats. These data indicate that interventions suppressing TACE activity in the brain mitigate neuroinflammation, sympathetic activation and cardiac dysfunction in HF rats.

11.
BMJ Open ; 12(7): e058609, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798530

RESUMO

OBJECTIVE: The study aimed to evaluate the impact of the COVID-19 pandemic on levels of anxiety and depressive symptoms in children and adolescents. DESIGN: Cross-sectional surveys were carried out on the mental health of children; one survey was conducted before the COVID-19 pandemic and one into the pandemic, 15 months after the school closures and implementation of lockdown and social distancing. Demographic data and COVID-19 pandemic-related data were collected from specific parent-report and self-report questionnaires. PARTICIPANTS: Participants included children and adolescents between ages 6 and 16 years, attending a tertiary care hospital without any diagnosed major psychiatric or chronic disorder. ANALYSIS: Data were collected at two points (before the COVID-19 pandemic and during it) and compared. Levels of anxiety and depressive symptoms were compared and tested for statistically significant differences between these two points using appropriate statistical tests. Regression models were constructed to predict the factors affecting increased anxiety levels and depressive symptoms in the COVID-19 period. RESULTS: 832 and 1255 children/adolescents were included in the study during the pre-COVID-19 and COVID-19 times, respectively. The median age of the participants was 10 years (IQR=4 years). The median (IQR) Spence Children's Anxiety Scale score was 24 (12) at the pre-COVID-19 point and 31 (13) during the COVID-19 pandemic (p<0.001, r=-0.27). 11% and 16% of children reported being depressed at these two-time points, respectively (p=0.004, φc=-0.063). Regression analysis showed that many factors, including the duration of smartphone use, female gender and only child status, were associated with increased anxiety or depression levels. CONCLUSION: A large proportion of children had elevated anxiety and depressive symptoms during the pandemic relative to before the pandemic, suggesting a need for measures to engage children in healthy habits to protect children's mental health and continuous monitoring of children during such scenarios.


Assuntos
COVID-19 , Adolescente , Ansiedade/epidemiologia , COVID-19/epidemiologia , Criança , Pré-Escolar , Controle de Doenças Transmissíveis , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Saúde Mental , Pandemias
13.
Hypertension ; 79(9): 2016-2027, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35730432

RESUMO

BACKGROUND: Exercise has profound effects on cardiovascular function and metabolism in both physiological and pathophysiological states. The present study tested whether voluntary exercise would protect male offspring against maternal gestational hypertension-induced hypertensive response sensitization elicited by post-weaning high-fat diet (HFD). METHODS AND RESULTS: On low-lard-fat diet, offspring of both normotensive and hypertensive dams had comparable resting blood pressure, but HFD feeding elicited an enhanced increase in blood pressure (ie, hypertensive response sensitization) in sedentary offspring of hypertensive dams when compared with sedentary offspring of normotensive dams. The HFD fed sedentary offspring of hypertensive dams displayed greater sympathetic activity, enhanced pressor responses to centrally administered ANG II (angiotensin II) or leptin, and greater mRNA expression of proinflammatory cytokines, leptin, and a marker of blood-brain barrier leakage in the hypothalamic paraventricular nucleus. The enhanced blood pressure and central sympathetic activity in HFD-fed sedentary offspring of hypertensive dams were significantly reduced by exercise but fell only to levels comparable to HFD-fed exercising offspring of normotensive dams. HFD-induced increases in plasma IL-6 (interleukin-6) and sympathetic activity and greater pressor responses to central TNF (tumor necrosis factor)-α in offspring from both normotensive and hypertensive dams were also maintained after exercise. Nevertheless, exercise had remarkably beneficial effects on metabolic and autonomic function, brain reactivity to ANG II and leptin and gene expression of brain prohypertensive factors in all offspring. CONCLUSIONS: Voluntary exercise plays a beneficial role in preventing maternal hypertension-induced hypertensive response sensitization, and that this is associated with attenuation of enhanced brain reactivity and centrally driven sympathetic activity.


Assuntos
Hipertensão Induzida pela Gravidez , Efeitos Tardios da Exposição Pré-Natal , Animais , Pressão Sanguínea/fisiologia , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Leptina , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Ratos , Ratos Sprague-Dawley
14.
Cureus ; 14(3): e23342, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35464556

RESUMO

Osteochondromas typically arise in the appendicular skeleton, with axial lesions occurring less commonly. Osteochondroma of the spine resulting in cord compression and symptomatic myelopathy is relatively rare. Most cases are reported in adolescents and adults. Consequently, there is a scarcity of literature regarding its occurrence in the pediatric population. We report the case of a cervical osteochondroma of C4-6 with cord compression in a nine-year-old girl. Surgical excision with laminectomy and laminotomy successfully resolved all neurologic deficits. A literature review revealed 27 cases of pediatric osteochondromas with cord compression, suggesting that these lesions are not as rare in the pediatric population as previously thought.

15.
Platelets ; 33(8): 1159-1167, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35473564

RESUMO

We have evaluated a commercial-fixed porcine platelet preparation (with and without added fixed human red blood cells (RBC)) for the potential standardization of mean platelet volume (MPV) measurements. The standards (Biotechne) were distributed internationally to 19 laboratories including all major hematology instrument manufacturers and academic/pathology laboratories. Overall, the standards demonstrated excellent stability up to 1 month within both MPV values and platelet counts when stored at 4°C. The presence of RBC significantly increased the platelet count and MPV values compared to platelets alone. However, as expected, there were differences in MPV values between different instruments and manufacturers. MPV values were also significantly higher in the whole blood standard compared to the platelet standard in the majority of instruments except with some instruments, where MPV values were significantly higher in the platelet only preparation. To further investigate this phenomenon, two different Platelet MPV preparations (with low and high MPV) in combination with 3 different RBC MCV preparations (with low, normal or high MCVs) were tested to try and further elucidate how RBC populations may impact upon platelet analysis (count, MPV, and PDW) using a single impedance analyzer. Both MPV and MCV values showed good stability over the course of the study for up to 50 days. As expected, the RBC preparation with the lowest MCV had the greatest impact on the MPV. However, this was not observed with an increase in MCV of the RBC or by a larger MPV of the platelet population. To further understand how different gating strategies may also influence results, we investigated the effect of either fixed or floating gate strategies upon MPV raw data from patient samples in a single impedance analyzer. Overall, it was clear that floating and fixed gate strategies also significantly impact upon MPV values. In conclusion, we have demonstrated the potential of an MPV standard with good stability characteristics for calibrating and comparing full blood counters that use different analysis principles, gating and MPV calculations. This may facilitate future instrument calibration and harmonization of results between different technologies.


Assuntos
Hematologia , Volume Plaquetário Médio , Animais , Plaquetas , Estudos de Viabilidade , Hematologia/métodos , Humanos , Contagem de Plaquetas/métodos , Padrões de Referência , Suínos
16.
Front Neurosci ; 16: 848079, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250473

RESUMO

Exercise training has profound effects on the renin-angiotensin system, inflammatory cytokines and oxidative stress, all of which affect autonomic nervous system activity and regulate blood pressure (BP) in both physiological and pathophysiological states. Using the Induction-Delay-Expression paradigm, our previous studies demonstrated that various challenges (stressors) during Induction resulted in hypertensive response sensitization (HTRS) during Expression. The present study tested whether voluntary exercise would protect against subpressor angiotensin (ANG) II-induced HTRS in rats. Adult male rats were given access to either "blocked" (sedentary rats) or functional running (exercise rats) wheels for 12 weeks, and the Induction-Delay-Expression paradigm was applied for the rats during the last 4 weeks. A subpressor dose of ANG II given during Induction produced an enhanced hypertensive response to a pressor dose of ANG II given during Expression in sedentary rats in comparison to sedentary animals that received saline (vehicle control) during Induction. Voluntary exercise did not attenuate the pressor dose of ANG II-induced hypertension but prevented the expression of HTRS seen in sedentary animals. Moreover, voluntary exercise reduced body weight gain and feed efficiency, abolished the augmented BP reduction after ganglionic blockade, reversed the increased mRNA expression of pro-hypertensive components, and upregulated mRNA expression of antihypertensive components in the lamina terminalis and hypothalamic paraventricular nucleus, two key brain nuclei involved in the control of sympathetic activity and BP regulation. These results indicate that exercise training plays a beneficial role in preventing HTRS and that this is associated with shifting the balance of the brain prohypertensive and antihypertensive pathways in favor of attenuated central activity driving sympathetic outflow and reduced BP.

17.
J Am Heart Assoc ; 11(2): e023685, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35014859

RESUMO

Background A recent study conducted in male offspring demonstrated that maternal gestational hypertension (MHT) induces hypertensive response sensitization (HTRS) elicited by postweaning high-fat diet (HFD). In this study, we investigated the sensitizing effect of MHT on postweaning HFD-induced hypertensive response in female rat offspring and assessed the protective role of estrogen in HTRS. Methods and Results The results showed that MHT also induced a sensitized HFD-elicited hypertensive response in intact female offspring. However, compared with male offspring, this MHT-induced HTRS was sex specific in that intact female offspring exhibited an attenuated increase in blood pressure. Ovariectomy significantly enhanced the HFD-induced increase in blood pressure and the pressor response to centrally administered angiotensin II or tumor necrosis factor-α in offspring of normotensive dams, which was accompanied by elevated centrally driven sympathetic activity, upregulated mRNA expression of prohypertensive components, and downregulated expression of antihypertensive components in the hypothalamic paraventricular nucleus. However, when compared with HFD-fed ovariectomized offspring of normotensive dams, the MHT-induced HTRS and pressor responses to centrally administered angiotensin II or tumor necrosis factor-α in HFD-fed intact offspring of MHT dams were not potentiated by ovariectomy, but the blood pressure and elicited pressor responses as well as central sympathetic tone remained higher. Conclusions The results indicate that in adult female offspring MHT induced HTRS elicited by HFD. Estrogen normally plays a protective role in antagonizing HFD prohypertensive effects, and MHT compromises this normal protective action of estrogen by augmenting brain reactivity and centrally driven sympathetic activity.


Assuntos
Hipertensão Induzida pela Gravidez , Efeitos Tardios da Exposição Pré-Natal , Angiotensina II , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Estrogênios/farmacologia , Feminino , Hipertensão Induzida pela Gravidez/prevenção & controle , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa
18.
Oxid Med Cell Longev ; 2022: 6371048, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35069977

RESUMO

Hemorrhagic shock is associated with activation of renin-angiotensin system (RAS) and endoplasmic reticulum stress (ERS). Previous studies demonstrated that central RAS activation produced by various challenges sensitizes angiotensin (Ang) II-elicited hypertension and that ERS contributes to the development of neurogenic hypertension. The present study investigated whether controlled hemorrhage could sensitize Ang II-elicited hypertension and whether the brain RAS and ERS mediate this sensitization. Results showed that hemorrhaged (HEM) rats had a significantly enhanced hypertensive response to a slow-pressor infusion of Ang II when compared to sham HEM rats. Treatment with either angiotensin-converting enzyme (ACE) 1 inhibitor, captopril, or ACE2 activator, diminazene, abolished the HEM-induced sensitization of hypertension. Treatment with the ERS agonist, tunicamycin, in sham HEM rats also sensitized Ang II-elicited hypertension. However, blockade of ERS with 4-phenylbutyric acid in HEM rats did not alter HEM-elicited sensitization of hypertension. Either HEM or ERS activation produced a greater reduction in BP after ganglionic blockade, upregulated mRNA and protein expression of ACE1 in the hypothalamic paraventricular nucleus (PVN), and elevated plasma levels of Ang II but reduced mRNA expression of the Ang-(1-7) receptor, Mas-R, and did not alter plasma levels of Ang-(1-7). Treatment with captopril or diminazene, but not phenylbutyric acid, reversed these changes. No treatments had effects on PVN protein expression of the ERS marker glucose-regulated protein 78. The results indicate that controlled hemorrhage sensitizes Ang II-elicited hypertension by augmenting RAS prohypertensive actions and reducing RAS antihypertensive effects in the brain, which is independent of ERS mechanism.


Assuntos
Angiotensina II/efeitos adversos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hemorragia/induzido quimicamente , Hipertensão/induzido quimicamente , Sistema Renina-Angiotensina/efeitos dos fármacos , Angiotensina II/farmacologia , Animais , Humanos , Masculino , Ratos , Ratos Wistar
19.
Cell Mol Neurobiol ; 42(4): 1141-1152, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33201417

RESUMO

Post-traumatic stress disorder (PTSD), an anxiety-related syndrome, is associated with increased risk for cardiovascular diseases. The present study investigated whether predator scent (PS) stress, a model of PTSD, induces sensitization of hypertension and anxiety-like behaviors and underlying mechanisms related to renin-angiotensin systems (RAS) and inflammation. Coyote urine, as a PS stressor, was used to model PTSD. After PS exposures, separate cohorts of rats were studied for hypertensive response sensitization (HTRS), anxiety-like behaviors, and changes in plasma levels and mRNA expression of several components of the RAS and proinflammatory cytokines (PICs) in the lamina terminalis (LT), paraventricular nucleus (PVN), and amygdala (AMY). Rats exposed to PS as compared to control animals exhibited (1) a significantly greater hypertensive response (i.e., HTRS) when challenged with a slow-pressor dose of angiotensin (ANG) II, (2) significant decrease in locomotor activity and increase in time spent in the closed arms of a plus maze as well as general immobility (i.e., behavioral signs of increased anxiety), (3) upregulated plasma levels of ANG II and interleukin-6, and (4) increased expression of message for components of the RAS and PICs in key brain nuclei. All the PS-induced adverse effects were blocked by pretreatment with either an angiotensin-converting enzyme antagonist or a tumor necrosis factor-α inhibitor. The results suggest that PS, used as an experimental model of PTSD, sensitizes ANG II-induced hypertension and produces behavioral signs of anxiety, probably through upregulation of RAS components and inflammatory markers in plasma and brain areas associated with anxiety and blood pressure control.


Assuntos
Hipertensão , Odorantes , Angiotensina II/farmacologia , Animais , Ansiedade/complicações , Modelos Animais de Doenças , Hipertensão/complicações , Hipertensão/metabolismo , Ratos , Ratos Sprague-Dawley
20.
Nanomaterials (Basel) ; 11(11)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34835687

RESUMO

The strain in hybrid van der Waals heterostructures, made of two distinct two-dimensional van der Waals materials, offers an interesting handle on their corresponding electronic band structure. Such strain can be engineered by changing the relative crystallographic orientation between the constitutive monolayers, notably, the angular misorientation, also known as the "twist angle". By combining angle-resolved photoemission spectroscopy with density functional theory calculations, we investigate here the band structure of the WS2/graphene heterobilayer for various twist angles. Despite the relatively weak coupling between WS2 and graphene, we demonstrate that the resulting strain quantitatively affects many electronic features of the WS2 monolayers, including the spin-orbit coupling strength. In particular, we show that the WS2 spin-orbit splitting of the valence band maximum at K can be tuned from 430 to 460 meV. Our findings open perspectives in controlling the band dispersion of van der Waals materials.

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