RESUMO
Soft X-rays are an important agent for chemical processing in the Solar System and in the interstellar medium. The photolysis and photodesorption processes of H2O-rich ices triggered by soft X-rays was, experimentally, addressed in this paper. The experiments were performed at the Brazilian synchrotron facility LNLS/CNPEN employing broadband radiation (from 6 to 2000 eV; mainly soft X-rays and a small fraction of VUV) in solid samples at temperatures of 20 and 80 K. The icy samples were monitored by infrared spectroscopy. We determined the effective destruction cross section (in the order 10-18 cm2) as well as the formation cross section for the new species produced after the irradiation. Among them, we list OCN-, CO, CO3, CH3OH, H2O2, HCOO-, NH4 +, HCONH2 and CH3HCO, mostly formed in the experiment at 80 K. The chemical equilibrium stage was characterized and molecular abundances were quantified. In addition, we discuss a methodology to estimate the amount of unknown species in the ice produced by photolysis. The samples reach chemical equilibrium at fluences around 2-3 × 1018 cm-2. Timescales for reaching chemical equilibrium in space environments illuminated by X-rays were given, as well as the desorption yields induced by X-rays. The astrophysical implication on the surface chemistry and desorption processes at the moon Enceladus are provided.
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OBJECTIVES: To generate and validate at pretest level a cross-culturally adapted Portuguese version of Xerostomia Inventory (XI), a 11-item questionnaire designed to measure specific xerostomia rating of patients complaints. METHODS: The original English version of the XI was translated into Portuguese following the guidelines for cross-cultural adaptation of health-related quality of life measures. Thirty patients with primary Sjögren syndrome were recruited for this study. The questionnaires were administered by trained and calibrated dental doctors to each patient. XI properties were examined including reliability, internal consistency, and test-retest reliability, using Cronbach's alpha, total and inter-item correlation, and intra-class correlation coefficients (ICC), respectively. Construct validity supported by objective measurements of xerostomia intra-oral signs and salivary secretion was investigated. Alpha was set at 0.05. Informed consents and local ethical committee clearance were obtained. RESULTS: Internal consistency and test-retest reliability were excellent (Cronbach's α=0.9; ICC range=0.79-0.94). Scatterplot interpolation and Pearson correlation coefficient suggested the presence of a strong, negative, and significant correlation between salivation and the XI scores indicating construct validity. CONCLUSION: The Portuguese version of the XI can be considered a reliable and valid instrument to measure patients' xerostomia symptoms.
Assuntos
Idioma , Inquéritos e Questionários , Tradução , Xerostomia/diagnóstico , Comparação Transcultural , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Portugal , Saliva/metabolismo , Taxa Secretória , Autorrelato , Síndrome de Sjogren/diagnóstico , Inquéritos e Questionários/normas , Xerostomia/fisiopatologiaRESUMO
Although imaging and clinical criteria are already established for the diagnosis of mucoid degeneration of the anterior cruciate ligament (ACL), many radiologists remain unaware of their existence. Once regarded as a rare occurrence, it has been recently suggested that its incidence is in fact very much higher than previously thought, and that it is probably underdiagnosed or misdiagnosed as partial ruptures of the ACL or as cystic ganglia. In this review, the authors revisit the literature concerning this subject and present their personal experience with it, stressing the paramount importance of magnetic resonance imaging and correlation with clinical data for a correct diagnosis.
Assuntos
Ligamento Cruzado Anterior/patologia , Artropatias/diagnóstico , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Envelhecimento , Diagnóstico Diferencial , Cistos Glanglionares/diagnóstico , Humanos , Muco , Amplitude de Movimento ArticularRESUMO
In this report seven cases of diffusely altered signal intensity of the posterior cruciate ligament (PCL) at magnetic resonance imaging (MRI) are described. The abnormalities resemble those of mucoid degeneration of the anterior cruciate ligament (ACL) and are associated with it in six cases. Although mucoid degeneration of the ACL is an increasingly reported entity, with well-established imaging criteria at MRI, to the authors' knowledge similar findings were never described before for the PCL. It is hypothesized that these abnormalities of the cruciate ligaments are similar in nature, probably related to degenerative changes of the connective tissue.
Assuntos
Ligamento Cruzado Anterior/patologia , Doenças do Tecido Conjuntivo/diagnóstico , Artropatias/diagnóstico , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Ligamento Cruzado Posterior/patologia , Adulto , Idoso , Doenças do Tecido Conjuntivo/complicações , Feminino , Humanos , Artropatias/complicações , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Amplitude de Movimento ArticularRESUMO
BACKGROUND: Anti-mullerian hormone (AMH) is a marker of ovarian function and reserve and reflects the number and size of antral follicles. The objective of this study was to evaluate the effect of FSH suppression on AMH levels, during the late luteal phase of human menstrual cycle, with the use of oral contraceptives pills (OCP). METHODS: Twenty normovulatory infertile women were included in the study. On the third day of a spontaneous menstrual cycle, the patients were submitted to a transvaginal ultrasound examination and blood sample collection. From the 20th day of this menstrual cycle, the patients took daily OCP, containing 0.030 mg of ethinyl-estradiol plus 0.15 mg of desogestrel. On the third day of the following cycle, the measurements were repeated. RESULTS: After OCP use, the levels of FSH and estradiol were significantly reduced (P < 0.001). The number of antral follicles measured on both occasions did not differ, although after OCP use, the follicles presented significantly lower diameters (mean 4.4 + 1.7 mm before OCP versus 3.5 + 1.2 mm after OCP P < 0.001). The levels of AMH were significantly reduced after pituitary suppression, with a median (inter-quartile range) of 3.02 ng/mL (1.21-6.39) before OCP and 2.22 ng/mL (0.9-3.11) after OCP, P = 0.04. CONCLUSIONS: The short administration of OCP in late luteal phase caused suppression of FSH secretion during the cycle transition, leading to a more homogeneous follicular cohort. The lower AMH levels observed, although simultaneous with FSH suppression, were probably not a direct effect of the reduced FSH levels, but were more likely a consequence of the lower production by the arrested follicular cohort.
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Hormônio Antimülleriano/sangue , Anticoncepcionais Orais Sintéticos/administração & dosagem , Desogestrel/administração & dosagem , Fase Luteal/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Adulto , Hormônio Antimülleriano/metabolismo , Biomarcadores/sangue , Estudos de Coortes , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Folículo Ovariano/metabolismo , Hipófise/efeitos dos fármacosRESUMO
PURPOSE: To evaluate power Doppler ultrasonography to predict sperm recovery in azoospermic patients. METHODS: Color Doppler and power Doppler ultrasonography of testis were performed in 38 patients before testicular sperm extraction. Analysis of blood flow included the pulsatility and resistance index of intratesticular vessels and testicular artery, and power Doppler of testis. The results of power Doppler of testis were classified into three categories: 0, no vessels found; 1, one to three vessels; 2, more than three vessels found. RESULTS: Power Doppler of both testis showed a significant difference between obstructive azoospermia and non-obstructive azoospermia (Fisher's exact test - P = 0.02), and between the groups with and without sperm recovery (Fisher's exact test - P = 0.001). Doppler indices of intratesticular vessels and testicular artery were similar between the groups. CONCLUSIONS: Testicular Power Doppler assessment showed that patients with obstructive azoospermia have better blood flow than patients with non-obstructive azoospermia, and power Doppler is able to predict sperm recovery in azoospermic patients.
Assuntos
Oligospermia/diagnóstico por imagem , Espermatozoides , Testículo/diagnóstico por imagem , Coleta de Tecidos e Órgãos , Adulto , Estudos Transversais , Humanos , Masculino , Fluxo Sanguíneo Regional , Testículo/irrigação sanguínea , Ultrassonografia DopplerRESUMO
Pseudotumoural hemicerebellitis is exceedingly rare. It may closely resemble a tumour either clinically or on imaging, and a high index of suspicion is required to avoid unnecessary surgical procedures. MRI is the most useful diagnostic tool, and reveals a swollen cerebellar hemisphere, hyperintense in T(2) weighted images. A pattern of predominantly pial contrast enhancement, absence of a well-defined mass and regression of the abnormalities in follow up examinations help to rule out malignancy. We report two cases of pseudotumoural cerebellitis (an 11-year-old girl and a 9-year-old boy) studied with CT and MRI.
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Doenças Cerebelares/diagnóstico , Encefalite/diagnóstico , Neoplasias Cerebelares/diagnóstico , Criança , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: In the present article we propose to evaluate IGF-1, IGFBP-1 and 3 in the follicular fluid of infertile patients submitted to in vitro fertilization. METHODS: We performed a case-control study with 53 infertile patients submitted to the first in vitro fertilization attempt. We compared their follicular fluid concentration of IGF-1, IGFBP-1 and IGFBP-3 between the patients who became pregnant (n = 11) versus those nonpregnant (n = 42). RESULTS: The clinical characteristics of patients from the two groups were similar in terms of age and body mass index. Data related to the analysis of ovulation induction was not different regarding length of induction in days, number of retrieved oocytes, fertilization rate, and number of transferred embryos. Furthermore, the number of FSH units required for ovarian induction was also similar between the studied groups. IGF-1 and IGFBP-1 were not significantly different between the groups (p > 0.05). However, those patients that became pregnant presented a lower follicular fluid concentration of IGFBP-3, 2237.10 +/- 582.73 pg/ml and 2657.64 +/- 584.15 ng/ml, respectively (p = 0.038). CONCLUSIONS: We demonstrated an association of a lower follicular fluid IGFBP-3 in individuals that became pregnant compared to subjects that did not after in vitro fertilization.
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Fertilização in vitro , Líquido Folicular/metabolismo , Infertilidade Feminina/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Folículo Ovariano/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , GravidezRESUMO
OBJECTIVE: The objective of the present study was to assess the predictive value of hormone values, histological analysis for the finding of motile spermatozoa on testicular biopsy in nonobstructive azoospermia. METHODS: This cross-sectional study assessed serum follicle-stimulating hormone (FSH), luteinizing hormone, prolactin and total testosterone values in 50 patients undergoing testicular biopsy prior to ICSI. P < 0.05 was considered significant. RESULTS: Recovery was successful in 28 cases, and motile spermatozoa were retrieved in 7. Significant differences were detected between presence of motile spermatozoa and absence of spermatozoa in terms of FSH values (P = 0.003, one-way ANOVA). The other variables did not present statistical differences. A receiver operating characteristic curve showed that FSH levels below 17.00 IU/L were predictive of motile spermatozoa recovery. CONCLUSIONS: FSH values can serve as a predictive factor for the recovery of motile spermatozoa using biopsy in azoospermic patients. On the other hand, histological analysis and other hormone values were not helpful in the prediction of motile sperm.
Assuntos
Oligospermia , Motilidade dos Espermatozoides , Espermatozoides , Testículo/citologia , Coleta de Tecidos e Órgãos/métodos , Biópsia , Estudos Transversais , Humanos , Masculino , Valor Preditivo dos TestesRESUMO
BACKGROUND: Endometriosis is associated with pituitary-ovarian axis dysfunction. The study of the follicular fluid in patients with endometriosis is important to elucidate the pathophysiological mechanism of this disease. The objective of this present paper was to analyse the dosages of insulin-like growth factor-1 (IGF-1) and IGF binding protein-1 and 3 (IGFBP-1 and IGFBP-3) in the follicular fluid environment of infertile patients with endometriosis. METHODS: A total of 41 infertile patients undergoing IVF between January 1999 and January 2000 participated in the cross-sectional prospective study. Patients were divided into three groups: group I, minimal/mild endometriosis (n = 12); group II, moderate/severe endometriosis (n = 10); and group III, tubal obstruction (n = 19). The ultra-short protocol was used in association with recombinant FSH for ovulation induction. Follicular fluid analysis was performed using radioimmunoassay with specific kits. RESULTS: Follicular fluid IGF-1 and IGFBP-3 levels were not significantly different among the groups; however, follicular fluid IGFBP-1 levels were lower in those patients with moderate/severe endometriosis (P < 0.05). Comparison of ovulation induction time, number of recombinant FSH units, number of follicles, oocytes and embryos, and fertilization and gestation/cycle rates showed non-significant differences. CONCLUSION: Infertile patients with moderate/severe endometriosis, which is associated with ovulatory dysfunction, presented lower levels of IGFBP-1 in the follicular fluid when undergoing IVF.
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Endometriose/complicações , Líquido Folicular/metabolismo , Infertilidade Feminina/etiologia , Infertilidade Feminina/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Adulto , Estudos Transversais , Feminino , Humanos , Concentração Osmolar , Estudos ProspectivosRESUMO
BACKGROUND: This study examines the effects of long-term continuous exposure to light on dopaminergic supersensitivity induced by repeated treatment with haloperidol in rats. METHODS: Spontaneous general activity in an open-field (SGA) and stereotyped behavior induced by apomorphine (SB-APO) or amphetamine (SB-AMP) were used as experimental parameters. Rats were allocated to four groups in each experiment: saline-treated animals kept under a 12-hour light/dark cycle (LD) or 24-hour light/light cycle (LL), and 2 mg/kg haloperidol-treated animals kept under the above cycles. Plasma corticosterone concentration was also measured by radioimmunoassay in saline-treated rats kept under a LD or LL cycle. RESULTS: All the behavioral parameters used showed the development of central dopaminergic supersensitivity in rats kept under both cycles. Continuous exposure to light enhanced SGA and SB-AMP in both saline- and haloperidol-treated rats, but did not modify SB-APO. Animals kept under the LL cycle presented an increased plasma corticosterone concentration. CONCLUSIONS: Our results suggest that continuous exposure to light leads to an increase in dopaminergic function in both normal and "supersensitive" rats. This effect seems to be mediated by a presynaptic mechanism possibly involving corticosterone actions.
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Antipsicóticos/efeitos adversos , Apomorfina/efeitos adversos , Dextroanfetamina/efeitos adversos , Dopaminérgicos/efeitos adversos , Agonistas de Dopamina/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Haloperidol/efeitos adversos , Luz/efeitos adversos , Transtorno de Movimento Estereotipado/induzido quimicamente , Animais , Comportamento Animal/efeitos dos fármacos , Corticosterona/sangue , Corticosterona/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Receptores Pré-Sinápticos/metabolismo , Fatores de TempoRESUMO
Infection by human T-cell lymphotrophic virus type I (HTLV-I) is associated with a myelopathy known as tropical spastic paraparesis (TSP). The prevalence of HTLV-I infection was found to be high in a pilot study in Bahia, Brazil. In the present study, among patients with myelopathy of unclear etiology, 27% (17/62) were immunoblot reactive to HTLV-I/II (serum and CSF), but none of 40 consecutive patients seen at the neurological clinic and having a well-established neurological diagnosis had detectable antibodies against those viruses (discrimination between HTLV-I and HTLV-II was not possible with the tests we used). The clinical syndrome of typical TSP with upper limb hyperreflexia was found to be a significant feature among the HTLV-I/II-seropositive patients compared to seronegative individuals. The 17 HTLV-I/II-reactive individuals had negative tests for syphilis, toxoplasmosis and schistosomiasis. TSP was also associated with female gender (P = 0.001). We conclude that TSP is strongly associated with HTLV-I/II infection in women in Bahia.
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Infecções por HTLV-I/complicações , Infecções por HTLV-II/complicações , Paraparesia Espástica Tropical/virologia , Doenças da Medula Espinal/virologia , Adulto , Brasil , Feminino , Anticorpos Anti-HTLV-I/sangue , Anticorpos Anti-HTLV-II/sangue , Humanos , Masculino , Paraparesia Espástica Tropical/sangue , Doenças da Medula Espinal/sangueRESUMO
Infection by human T-cell lymphotrophic virus type I (HTLV-I) is associated with a myelopathy known as tropical spastic paraparesis (TSP). The prevalence of HTLV-I infection was found to be high in a pilot study in Bahia, Brazil. In the present study, among patients with myleopathy of unclear etiology, 27 per cent (17/62) were immunoblot reactive to HTLV-I/II (serum and CSF), but none of 40 consecutive patients seen at the neurological clinic and having a well-established neurological diagnosis had detectable antibodies against those viruses (discrimination between HTLV-I and HTLV-II was not possible with the tests we used). The clinical syndrome of typical TSP with upper limb hyperreflexia was found to be a significant feature among the HTLV-I/II-seropositive patients compared to seronegative individuals. The 17 HTLV-I/II-reactive individuals had negative tests for syphilis, toxoplasmosis and schistosomiasis. TSP was also associated with female gender (P=0.001). We conclude that TSP is strongly associated with HTLV-I/II infection in women in Bahia.
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Humanos , Masculino , Feminino , Adulto , Doenças da Medula Espinal/etiologia , Infecções por HTLV-I/complicações , Infecções por HTLV-II/complicações , Paraparesia Espástica Tropical/etiologia , Brasil , Eletromiografia , Anticorpos Anti-HTLV-I/análise , Anticorpos Anti-HTLV-II/análise , Imunoensaio , Reflexo Anormal , Fatores SexuaisRESUMO
1. To determine whether the association between mitral valve prolapse and Graves' disease is related to thyroid function, three groups of individuals were studied: 16 patients with Graves' disease and hyperthyroidism (hyperthyroid: T4 greater than 11.5 micrograms/100 ml), 16 patients with Graves' disease without hyperthyroidism (euthyroid: T4 less than 11.5 micrograms/100 ml), and 40 healthy individuals. The three groups were similar in age, sex distribution, and anthropometrical characteristics. 2. All patients were evaluated clinically and by M-mode and two-dimensional echocardiography to determine the presence of mitral valve prolapse. 3. The frequency of mitral valve prolapse was similar in the hyperthyroid (31%) and euthyroid patients (25%), but was higher than in the normal individuals (5%). The frequency of systolic murmur was higher in the hyperthyroid patients (75%) than the euthyroid patients (19%) or the normal subjects (0%); however, the presence of a murmur was not associated with mitral valve prolapse. Hyperthyroid (13%) and euthyroid (13%) patients had a higher frequency of clicks than the normal individuals (0%), and the presence of click was associated with mitral valve prolapse. 4. Although patients with Graves' disease have a higher frequency of mitral valve prolapse, this is not associated with thyroid function. The presence of a click but not the presence of a systolic murmur may be a clinical indicator of mitral valve prolapse in Graves' disease.
Assuntos
Doença de Graves/complicações , Prolapso da Valva Mitral/complicações , Adulto , Ecocardiografia , Feminino , Doença de Graves/fisiopatologia , Humanos , Hipertireoidismo/fisiopatologia , Masculino , Prolapso da Valva Mitral/fisiopatologia , Prognóstico , Estudos Prospectivos , Testes de Função TireóideaRESUMO
To determine whether the association between mitral valve prolapse and Graves' disease is related to thyroid function, three groups of individuals were studied: 16 patients with Graves' disease and hyperthyroidism (hyperthyroid: T4 > 11.5 microng/100 ml), 16 patients with Graves' disease without hyperthyroidism (euthyroid: T4 < 11.5 microng/100 ml), and 40 healthy individuals. The three groups were similar in age, sex distribution, and anthropometrical characteristics. All apatients were evaluated clinically and by M-mode and two-dimensional echocardiopgraphy to determine the presence of mitral valve prolapse. The frequency of mitral valve prolapse was similar in the hyperthyroid (31%) and euthyroid patients (25%), but was higher than in the normal individuals (5%). The frequency of systolic murmur was in the hyperthyroid patients (75%) than the euthyroid patients (19%) or the normal subjects (0%); however, the presence of a murmur was not associated with mitral valve prolapse. Although patients with Graves' disease have a higher frequency of mitral valve prolapse, this is not associated with thyroid function. The presence of a click but not the presence of a systolic murmur may be a clinical indicator of mitral valve prolapse in Graves' disease
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Doença de Graves/complicações , Prolapso da Valva Mitral/etiologia , Glândula Tireoide/fisiopatologia , Ecocardiografia , Hipertireoidismo/fisiopatologia , Prolapso da Valva Mitral/diagnóstico , Prognóstico , Estudos ProspectivosRESUMO
1. In order to evaluate the mechanism by which beta blockers with intrinsic sympathomimetic activity preserve left ventricular systolic function at rest, 46 patients with coronary artery disease were studied by right and left heart catheterization and left ventriculography. Patients were studied using a double-blind, randomized protocol before and after a single intravenous dose of 3 mg propranolol (N = 22) or 0.5 mg pindolol (N = 24). 2. Mean right atrial pressure increased similarly after both drugs. Mean pulmonary artery pressure, left ventricular end-diastolic pressure, mean aortic pressure, and peripheral vascular resistance did not change significantly after either drug. Cardiac index (before: 3.0 +/- 0.7 (mean +/- SEM); after: 2.8 +/- 0.2 1 min-1 m-2) and heart rate (before: 78 +/- 15; after: 72 +/- 12 bpm) decreased only after propranolol administration. 3. Ejection fraction decreased only after propranolol (48 +/- 16 to 41 +/- 15%). Improvement in segmental wall motion abnormalities was noted (23 of 47 segments) only after pindolol. The total left ventricular wall motion score improved after pindolol and worsened after propranolol (P less than 0.05). In patients with impaired left ventricular function, pindolol administration resulted in improved resting ejection fraction. 4. Thus, the acute hemodynamic consequences of pindolol administration differ from those of propranolol owing to the preservation of left ventricular systolic function which seems to be related to the intrinsic sympathomimetic effect of pindolol on areas of reversible wall motion abnormality.
Assuntos
Doença das Coronárias/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Pindolol/farmacologia , Propranolol/farmacologia , Adulto , Idoso , Análise de Variância , Pressão Sanguínea/efeitos dos fármacos , Cateterismo Cardíaco , Ensaios Clínicos como Assunto , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , RadiografiaRESUMO
In order to evaluate the mechanism by which beta blockers with intrinsic sympathomimetic activity preserve left ventricular systolic function at rest, 46 patients with coronary artery disease were studied by right and left heart catheterization and left ventriculography. Patients were studied using a double-blind, randomized protocol before and after a single intravenous dose of 3 mg propanolol (N = 22) or 0.5 mg pindolol (N = 24). Mean right atrial pressure increased similarly after both drugs. Mean pulmonary artery pressure, left ventricular end-diastolic pressure, mean aortic pressure, and peripheral vascular resistance did not change significantly after either drug. Cardiac index (before: 3.0 + or - 0.7(mean + or - SEM); after: 2.8 + or - 0.2 1 min **-1 m**-2) and heart rate (before: 78 + or - 15; after: 72 + or - 12 bpm) deveased only after propranolol administration. Ejection fraction decreased only after propranolol (48 + or - 16 to 41 + or - 15%). Improvement in segmental wall motion abnormalities was noted (23 of 47 segments) only after pindolo. The total left ventricular wall motion score improved after pindolol and worsened after propranolol (P<0.5). In patients with impaired left ventricular function, pindolol administration resulted in improved resting ejection fraction. Thus, the acute hemodynamic consequences of pindolol administration differ from those of propranolol owing to the preservation of left ventricular systolic function which seem to be related to the...