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BACKGROUND: The growth of the heart during the foetal and early postnatal development takes places mainly due to hyperplasia. The late postnatal development is characterised by cardiomyocytic hypertrophy in response to normal physiological mechanisms and increased load. To study the cell size most authors measure the diameter either directly or indirectly. AIM: The aim of the present study was to make a comparative quantitative analysis of the postnatal changes observed in the left and right ventricles in rat by evaluating the changes in three morphometric parameters - thickness of the free wall, transverse section of the cardiomyocytes and cardiomyocytic density in the left ventricle and right ventricle. MATERIALS AND METHODS: In the present study, we used histological material from the hearts of 15 male Wistar rats, distributed in five groups aged 2 weeks, 1 month, 3 months, 6 months and 12 months, respectively. RESULTS: In both ventricles, the wall thickness and the transverse section of the cardiomyocytes increased with age, while the cardiomyocytic density decreased. Changes were identical in both ventricles; however, they were more dynamic and pronounced in the left ventricle. CONCLUSIONS: The studied morphometric parameters reveal that age-related hypertrophy and the gradual loss of cardiac muscle cells take place in both ventricles but have a more dynamic pattern of progression in the left ventricle as compared with the right ventricle.
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Ventrículos do Coração/crescimento & desenvolvimento , Coração/crescimento & desenvolvimento , Miocárdio/citologia , Miócitos Cardíacos/citologia , Animais , Contagem de Células , Crescimento Celular , Hipertrofia , Masculino , Tamanho do Órgão , Ratos , Ratos WistarRESUMO
INTRODUCTION: It has been published that patients who underwent gastric bypass surgery have impaired alcohol metabolism, predisposing them to higher rates of intoxication and DUI arrests. Yet the impact of laparoscopic sleeve gastrectomy (LSG) on alcohol metabolism and in particular the long-term effects are still unclear. We hypothesized that LSG does not alter alcohol metabolism. METHODS: A prospective cohort study of patients undergoing LSG was evaluated. Blood alcohol concentration (BAC) was extrapolated using a Breathalyzer(®). Alcohol metabolism was evaluated by determining BAC every 5 min after a single dose of alcohol (5 oz. glass of 14% v/v Malbec wine), until BAC was equal to zero. Subjects were queried about alcohol intoxication symptoms. All parameters were obtained and analyzed preoperatively and at 3 and 12 months postoperatively. RESULTS: Our study consisted of 10 patients (9 female) with a mean age of 46.6 ± 2.2 years and BMI of 43.5 ± 2.2 kg/m(2). The mean percentage excess weight loss was 39.5 ± 3.3 at 3 months and 55.6 ± 4.4 at 12 months. Peak BAC at 20 min was not different at 3 months (0.068 ± 0.007, p = 0.77) or at 12 months (0.047 ± 0.008, p = 0.19) when compared to the preoperative assessment (0.059 ± 0.014). In addition, the time to BAC equal to zero was not significantly different between baseline and the follow-up values (preoperative: 70 ± 9 min, 3 months: 95 ± 18 min, and 12 months: 57 ± 8 min, (p > 0.05). Symptoms of intoxication were not significantly different in patients before and after surgery. CONCLUSIONS: Our study suggests that LSG does not alter alcohol metabolism. Patients who undergo LSG do not have higher levels of intoxication following alcohol consumption and are therefore not prone to higher rates of DUI charges than the general public, in contrast to that previously reported following in patients who undergo gastric bypass surgery.
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Etanol/farmacocinética , Gastrectomia/métodos , Obesidade Mórbida/cirurgia , Testes Respiratórios , Etanol/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/sangue , Período Pós-Operatório , Estudos Prospectivos , Redução de PesoRESUMO
BACKGROUND: Tirzepatide has recently been approved for the treatment of type 2 diabetes mellitus (T2DM), based on its impressive effects on glycemia and body weight reduction. We investigated whether tirzepatide affects the risk for cancer in T2DM. METHODS: We conducted a meta-analysis of available, up to 1st April 2024, phase 2/3 randomized controlled trials (RCTs) evaluating the use of tirzepatide in T2DM. We set as primary safety endpoint the risk for any type of cancer, while we assessed as secondary endpoints specific cancer types. Subgroup analyses according to the type of comparator were also performed. RESULTS: We included a total of 9 RCTs with a relatively short study duration, ranging from 36 to 72 weeks. Our preliminary evidence suggests that tirzepatide does not increase the risk for any cancer (primary outcome) or any of the specific cancer types (secondary outcomes). Of course, small number of enrolled participants, short study duration and follow-up, along with scarcity of reported events are considered to be main limitations of the present analysis. CONCLUSIONS: Preliminary evidence from our analysis suggests that tirzepatide may not affect the risk ofcancer among individuals with T2DM. However, our results should be interpreted with extra caution, based on the several limitations of our "hypothesis-generating" analysis Future, well-designed studies are warranted to answer this important research question.
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Diabetes Mellitus Tipo 2 , Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Neoplasias/epidemiologia , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversosRESUMO
Oncofertility is an extremely significant topic that is increasingly being discussed owing to increased evidence indicating that fertility preservation does not affect the treatment outcomes of patients with cancer but significantly contributes to preserving life quality. The effect of chemotherapy can range from minimal effects to complete ovarian atrophy. Limited data are available on the effects of monoclonal antibodies and targeted therapies on the ovaries and fertility. Temporary ovarian suppression by administering a gonadotropin-releasing hormone agonist (GnRHa) during chemotherapy decreases the gonadotoxic effect of chemotherapy, thereby diminishing the chance of developing premature ovarian insufficiency (POI). At present, the concomitant administration of GnRH analogs during chemotherapy is the only accepted pharmacological method for preserving ovarian function. Notably, most randomized studies on the effectiveness of luteinizing hormone-releasing hormone agonists during chemotherapy in preventing POI have been conducted in women with breast cancer, with a considerably small number of studies on patients with hematological malignancies. Furthermore, most randomized controlled trials on breast cancer have revealed a decrease in treatment-induced POI risk, regardless of the hormone receptor status. In addition, studies on hematological malignancies have yielded negative results; nevertheless, the findings must be interpreted with caution owing to numerous limitations. Current guidelines from the American Society of Clinical Oncology and ESMO Clinical Practice Guidelines recommend sperm, oocyte, and embryo cryopreservation as a standard practice and only offering GnRHa to patients when proven fertility preservation methods are not feasible. In this manuscript, we present a comprehensive literature overview on the application of ovarian suppression with GnRHa during chemotherapy in patients with cancer by addressing preclinical and clinical data, as well as future perspectives in this field that upcoming research should focus on.
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Preservação da Fertilidade , Hormônio Liberador de Gonadotropina , Neoplasias , Ovário , Insuficiência Ovariana Primária , Humanos , Preservação da Fertilidade/métodos , Feminino , Neoplasias/tratamento farmacológico , Ovário/efeitos dos fármacos , Ovário/metabolismo , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/prevenção & controle , Hormônio Liberador de Gonadotropina/agonistas , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Criopreservação/métodosRESUMO
Triple-negative breast cancer (TNBC) is a disease with often an aggressive course and a poor prognosis compared to other subtypes of breast cancer. TNBC accounts for approximately 10%-15% of all diagnosed breast cancer cases and represents a high unmet need in the field. Up to just a few years ago, chemotherapy was the only systemic treatment option for this subtype (1). To date, TNBC is considered a heterogeneous disease. One of the existing classifications is based on the analysis of mRNA expression in 587 TNBC cases, in which Lehman et al. proposed six subtypes of TNBC as follows: two basal-like (BL1 and BL2) subtypes, a mesenchymal (M) subtype, a mesenchymal stem-like (MSL) subtype, an immunomodulatory (IM) subtype, and a luminal androgen receptor (LAR) subtype (2). Later studies have demonstrated that the IM and MSL subtypes do not correlate with independent subtypes but reflect background expression by dense infiltration of tumor-infiltrating lymphocytes (TILs) or stromal cells. According to this finding, the classification of TNBC has been revised into the following four subtypes: basal 1, basal 2, LAR, and mesenchymal subtypes (3). Over the last years, several new strategies have been investigated for the treatment of patients with TNBC. Among them, immunotherapy, antibody drug conjugates, new chemotherapy agents, and targeted therapy have been and are currently being developed. The present article aims to provide an updated overview on the different treatment options that are now available or are still under investigation for patients with TNBC.
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Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Imunoterapia , Imunomodulação , Linfócitos do Interstício TumoralRESUMO
Renal cell cancer (RCC) represents 2%-3% of all adulthood cancers and is the most common malignant neoplasm of the kidney (90%). In the mid-nineties of the last century, the standard of treatment for patients with metastatic RCC was cytokines. Sunititib and pazopanib were registered in 2007 and 2009, respectively, and have since been the standard first-line treatment for metastatic clear cell RCC (mccRCC). Renal cell cancer is a highly immunogenic tumor with tumor infiltrating cells, including CD8+ T lymphocytes, dendritic cells, natural killer cells (NK) and macrophages. This observation led to the design of new clinical trials in which patients were treated with immunotherapy. With the growing evidence that proangiogenic factors can have immunomodulatory effects on the host's immune system, the idea of combining angiogenic drugs with immunotherapy has emerged, and new clinical trials have been designed. In the last few years, several therapeutic options have been approved [immunotherapy and immunotherapy/tyrosine kinase inhibitors (TKI)] for the first-line treatment of mccRCC. Nivolumab/ipilimumab is approved for the treatment of patients with intermediate and poor prognoses. Several checkpoint inhibitors (pembrolizumab, nivolumab, avelumab) in combination with TKI (axitinib, lenvatinib, cabozantinib) are approved for the treatment of patients regardless of their International mRCC Database Consortium prognostic group and PD-L1 expression. There is no specific and ideal biomarker that could help in selecting the ideal patient for the appropriate first-line treatment.
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The possibilities of computer tomography (CT) for differential diagnosis of adrenal incidentalomas (AI) were investigated. CT was done for 157 patients with AT: 17--with malignant adrenal tumors (MAT) and 70--with benign adrenal tumors (BAT) (61--adrenocortical adenoma, 5--cyst, 3--hematoma, 1--myelolipoma). CT--main method of topic diagnostic for AI, which allow to make assumption about potential malignancy AI in 76.5% patients. Incidentalomas size more than 10,1sm, irregular contours, density more +51HU, signs of invasion, lymphadenopathy, regional or remote metastasis are the diagnostic criteria for MAT. In 23.5% cases with CT impossible to differentiate the malignant nature of AI. 10.0% patients with BAT had a false positive results, which slightly limits the diagnostic value of CT.
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Neoplasias das Glândulas Suprarrenais/diagnóstico , Doenças das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Adulto JovemRESUMO
Relapsed or refractory non-Hodgkin's lymphomas, especially diffuse large B-cell lymphoma as well as relapsed or refractory Hodgkin lymphomas are hard-to-treat diseases. Patients who do not respond to initial therapy or experience relapse are treated with salvage regimens, and if eligible for aggressive therapy, treatment is continued with high-dose chemotherapy and autologous stem cell transplantation. Current therapy options can cure substantial numbers of patients, however for some it is still an uncurable disease. Numerous new drugs and cell therapies are being investigated for the treatment of relapsed or refractory lymphomas. Different types of immunotherapy options have shown promising results, and some have already become the standard of care. Here, we review immunotherapy options for the treatment of lymphoma and discuss the results, positions, practical aspects, and future directions of different drugs and cellular therapies for the treatment of this disease.
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INTRODUCTION: Ca2+ regulatory excitation-contraction coupling properties are key topics of interest in the development of work-related muscle myalgia and may constitute an underlying cause of muscle pain and loss of force generating capacity. METHOD: A well-established rat model of high repetition high force (HRHF) work was used to investigate if such exposure leads to an increase in cytosolic Ca2+ concentration ([Ca2+]i) and changes in sarcoplasmic reticulum (SR) vesicle Ca2+ uptake and release rates. RESULT: Six weeks exposure of rats to HRHF increased indicators of fatigue, pain behaviors, and [Ca2+]i, the latter implied by around 50-100% increases in pCam, as well as in the Ca2+ handling proteins RyR1 and Casq1 accompanied by an â¼10% increased SR Ca2+ uptake rate in extensor and flexor muscles compared to those of control rats. This demonstrated a work-related altered myocellular Ca2+ regulation, SR Ca2+ handling, and SR protein expression. DISCUSSION: These disturbances may mirror intracellular changes in early stages of human work-related myalgic muscle. Increased uptake of Ca2+ into the SR may reflect an early adaptation to avoid a sustained detrimental increase in [Ca2+]i similar to the previous findings of deteriorated Ca2+ regulation and impaired function in fatigued human muscle.
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Cálcio/metabolismo , Músculo Esquelético/metabolismo , Doenças Musculares/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Citosol/metabolismo , Modelos Animais de Doenças , Acoplamento Excitação-Contração/fisiologia , Feminino , Proteínas Mitocondriais/metabolismo , Contração Muscular/fisiologia , Mialgia/metabolismo , Ratos , Ratos Sprague-Dawley , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismoRESUMO
Checkpoint inhibitors are monoclonal antibodies attach to several different receptors on T-cells or tumour cells expressing receptors for cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed death-1 (PD-1) and their ligand (PD-L1). Since 2010, numerous trials on different tumour types have been conducted, which was resulted in these drugs being approved for the treatment of melanoma, lung cancer, Hodgkin's lymphoma and head and neck cancers. Urological cancers, especially urothelial and renal-cell carcinomas, are immunogenic tumours. Since the late 70s, the bacillus Calmette-Gurin (BCG) vaccine has been used for intravesical instillation in non-muscle invasive bladder cancer from the mid-90s up until the discovery of tyrosine kinase inhibitors (TKIs) in 2007, interleukin-2 (IL-2) and interferon alpha (IFNα), which were the standard of care for metastatic renal-cell cancer. Two checkpoint inhibitors are already approved by the Food and Drug Administration: atezolizumab for metastatic urothelial cancer and nivolumab for metastatic renal-cell carcinoma. There are many drugs are in different phases of clinical development. Here we review the current status of checkpoint inhibitors in the treatment of urological tumours.
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Nowadays, aberration corrected transmission electron microscopy (TEM) is a popular method to characterise nanomaterials at the atomic scale. Here, atomically resolved images of nanomaterials are acquired, where the contrast depends on the illumination, imaging and detector conditions of the microscope. Visualization of light elements is possible when using low angle annular dark field (LAADF) STEM, annular bright field (ABF) STEM, integrated differential phase contrast (iDPC) STEM, negative spherical aberration imaging (NCSI) and imaging STEM (ISTEM). In this work, images of a NdGaO3-La0.67Sr0.33MnO3 (NGO-LSMO) interface are quantitatively evaluated by using statistical parameter estimation theory. For imaging light elements, all techniques are providing reliable results, while the techniques based on interference contrast, NCSI and ISTEM, are less robust in terms of accuracy for extracting heavy column locations. In term of precision, sample drift and scan distortions mainly limits the STEM based techniques as compared to NCSI. Post processing techniques can, however, partially compensate for this. In order to provide an outlook to the future, simulated images of NGO, in which the unavoidable presence of Poisson noise is taken into account, are used to determine the ultimate precision. In this future counting noise limited scenario, NCSI and ISTEM imaging will provide more precise values as compared to the other techniques, which can be related to the mechanisms behind the image recording.
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Vertically aligned well-separated N-doped multiwalled carbon nanotubes (CNTs) were grown on a silicon substrate by plasma enhanced chemical vapor deposition (PECVD). Angular near-edge X-ray absorption fine structure (NEXAFS) was used to investigate the vertical alignment of as-grown CNTs. In addition, both individual tubes and tube bundles were characterized by high-resolution electron energy loss spectroscopy (HREELS). Simultaneous analysis of both spectroscopic techniques provides information on chemical environment, orbital orientation between carbon and heteroatoms, and local curvature effects. We demonstrate the utility of NEXAFS as an in situ probe of CNTs.
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The significant enhancement of the energy resolution in the new generation of commercially available monochromated transmission electron microscopes presents new challenges in term of selecting the correct experimental conditions and understanding the various effects that can potentially influence the quality of the EELS data. In this respect we investigated the effect of point spread function of the detector and spectrum-diffraction mixing on the energy resolution and the intensity of the zero loss peak tails. Alternative approaches to improve the energy resolution by mathematical methods have been tested. By using a simple and commonly available test case (Si L(2,3) edges) we assessed the efficiency of the deconvolution algorithms to improve the resolution. The results show that the deconvolution is not always successful in improving the resolution of the core loss EELS data and the results may not always be reliable. Contrary to this, the application of the Richardson-Lucy deconvolution algorithm on some bandgap measurements data appears to be very effective. The procedure proved successful in removing the contribution of the zero-loss peak tails and allows an easier access to spectroscopic information starting at energy losses as low as of 0.5 eV with monochromated spectra and 1 eV with the non-monochromated spectra.
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Measuring low energy losses in semiconductors and insulators with high spatial resolution becomes attractive with the increasing availability of modern transmission electron microscopes (TEMs) equipped with monochromators, C(s) correctors and energy filters. In this paper, we demonstrate that Cerenkov losses pose a limit for the interpretation of low energy loss spectra (EELS) in terms of interband transistions and bandgap determination for many materials. If the velocity of a charged particle in a medium exceeds the velocity of light, photons are emitted leading to a corresponding energy loss of a few electronvolt. Since these losses are strong for energies below the onset of interband transitions, they change the apparent loss function of semiconductors and insulators, with the risk of erroneous interpretation of spectra. We measured low energy losses of Si and GaAs with a monochromated TEM demonstrating the effect of sample thickness on Cerenkov losses. Angle resolved EELS and energy filtered diffraction patterns (taken without a monochromator) show the extremely narrow angular distribution of Cerenkov losses. The latter experiment provides a method that allows to decide whether Cerenkov radiation masks the very low loss signal in EELS.
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The purpose of this study was to determine if knowledge of diabetes could be increased through use of a learning device designed for insulin-dependent diabetic children, aged 7-12 yr. The instrument, consisting of a book and game, combines cognitive and affective elements to provide diabetic information and to reinforce and to evaluate this knowledge in subjects. Serial exposure to the instrument resulted in a significant increase in knowledge and retention of information in 26 experimental subjects. Five subjects receiving one teaching intervention showed an initial increase in knowledge, but without reinforcement, demonstrated minimal retention. Six control subjects, receiving no intervention, showed no increase in knowledge.
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Diabetes Mellitus Tipo 1/tratamento farmacológico , Educação de Pacientes como Assunto , Materiais de Ensino , Criança , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Fatores de TempoRESUMO
Possibilities of application of magnet-resonance tomography (MRT) for differential diagnosis of the adrenal glands tumors were studied up. MRT was conducted to 39 patients with adrenal glands tumors, including 22 - with malignant adrenal gland tumor, 17 - with benign tumor of adrenal gland. MRT constitutes the most effective method of topic diagnosis of the adrenal glands tumor, owes multipurpose possibilities, do not deliver radiation load, permits to visualize the vessels without the contrast media usage. The tumor diameter more than 10,1 cm, irregular form, illegible edges, uneven contours, presence of lymphadenopathy, regional or remote metastases constitutes diagnostic criterions of the adrenal glands malignant tumors. The intensity of MRT signal could not be used for differential diagnosis of malignant and benign tumors of adrenal glands.
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Neoplasias das Glândulas Suprarrenais/diagnóstico , Imageamento por Ressonância Magnética , Doenças das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/patologia , Cistos/diagnóstico , Diagnóstico Diferencial , Humanos , Invasividade Neoplásica , Metástase NeoplásicaRESUMO
Possibilities of computer tomography (CT) application for differential diagnosis of tumors of the adrenal cortex (TAC) were studied. CT was conducted in 157 patients with TAC, including 75--with malignant (MTAC), 82--with benign (BTAC), permitting to revealed MTAC in 76% patients. In 17.1% patients with BTAC false-positive results were noted, reducing, thus, the method diagnostic value. While the trustworthy signs of malignancy are absent, it is necessary to conduct morphological verification of the adrenal tumors nature using puncture biopsy and/or intraoperative express-cytological investigation.
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Neoplasias do Córtex Suprarrenal/diagnóstico por imagem , Adenoma/diagnóstico por imagem , Adenoma/patologia , Adenoma/cirurgia , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Cistos/diagnóstico por imagem , Cistos/patologia , Cistos/cirurgia , Diagnóstico Diferencial , Reações Falso-Positivas , Hematoma/diagnóstico por imagem , Hematoma/patologia , Hematoma/cirurgia , Humanos , Lipoma/diagnóstico por imagem , Lipoma/patologia , Lipoma/cirurgia , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: The authors reviewed data involving the impact of providing psychotherapy for psychiatric disorders on costs of care. METHOD: In a search of the MEDLINE database limited to peer-reviewed papers published from 1984 through 1994, 686 articles were identified. Forty-one articles, covering 35 studies, were found in which the intervention tested was psychotherapeutic and the study included measures of outcome that had some implications for cost. The exclusion criteria for reviewing these studies included absence of a comparison group, a focus on medical disorders instead of psychiatric illnesses, and outcomes that did not include cost data or measures from which costs could be inferred. On this basis, 18 of the 35 studies were selected for analysis. The studies were categorized according to whether or not subjects were randomly assigned to study groups. Two reviewers independently read each study to identify the following characteristics: inclusion criteria, exclusion criteria, types of interventions, main outcome variables, sample size, and statistical tests for significant differences between treatments. Outcomes had to include actual cost accounting or data on medical care utilization or work functioning. RESULTS: The findings of eight (80%) of the 10 clinical trials with random assignment and all eight (100%) of the studies without random assignment suggested that psychotherapy reduces total costs. CONCLUSIONS: Psychotherapy appears to have a beneficial impact on a variety of costs when used in the treatment of the most severe psychiatric disorders, including schizophrenia, bipolar affective disorder, and borderline personality disorder. Much of that impact accrues from reductions in inpatient treatment and decreases in work impairment.
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Custos de Cuidados de Saúde , Transtornos Mentais/terapia , Psicoterapia/economia , Transtorno Bipolar/economia , Transtorno Bipolar/terapia , Transtorno da Personalidade Borderline/economia , Transtorno da Personalidade Borderline/terapia , Ensaios Clínicos como Assunto , Humanos , MEDLINE , Transtornos Mentais/economia , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto , Esquizofrenia/economia , Esquizofrenia/terapia , Resultado do TratamentoRESUMO
[reaction--see text] A variety of 2-substituted-2,3-dihydro-1,4-dioxino[2,3-b]pyridines B have been synthesized from the readily available 2-nitro-3-oxiranylmethoxypyridine 1 via a Smiles rearrangement. We demonstrate how variations of reaction conditions affect the product distribution of A and B.
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Dioxinas/síntese química , Piridinas/síntese química , Dioxinas/química , Desenho de Fármacos , Espectroscopia de Ressonância Magnética , Piridinas/químicaRESUMO
Meditation is a conscious mental process that induces a set of integrated physiologic changes termed the relaxation response. Functional magnetic resonance imaging (fMRI) was used to identify and characterize the brain regions that are active during a simple form of meditation. Significant (p<10(-7)) signal increases were observed in the group-averaged data in the dorsolateral prefrontal and parietal cortices, hippocampus/parahippocampus, temporal lobe, pregenual anterior cingulate cortex, striatum, and pre- and post-central gyri during meditation. Global fMRI signal decreases were also noted, although these were probably secondary to cardiorespiratory changes that often accompany meditation. The results indicate that the practice of meditation activates neural structures involved in attention and control of the autonomic nervous system.