Obstructive sleep apnea: lessons on clinic and surgery

Introdução: A síndrome da apnéia obstrutiva do sono (SAOS) é uma doença crônica e progressiva com alta morbimortalidade cardiovascular. A SAOS afeta 2-4% da população masculina entre 30 e 69 anos, e 1-2% da população feminina na mesma faixa etária, constituindo um problema de saúde pública. Fisiopatologia: A SAOS ocorre por associação de alterações anatômicas e um aumento na complacência da musculatura durante a passagem do ar. A musculatura das vias aéreas superiores relaxa durante o sono, causando uma redução das forças de dilatação das mesmas e episódios repetidos de obstrução. Cada obstrução é acompanhada por despertares e redução da saturação de oxigênio arterial, causando ativação aguda do sistema nervoso autônomo simpático com alterações cardiorrespiratórias. Aspectos Clínicos: Os sintomas da SAOS são noturnos e diurnos. Durante o sono, há a presença de roncos, pausas respiratórias, sono agitado, despertares e noctúria. Enquanto acordado, o paciente apresenta sintomas de sonolência diurna excessiva, dor de cabeça matinal, queda da função intelectual, sintomas depressivos, impotência sexual e distúrbios de personalidade. Os pacientes com SAOS são frequentemente homens, de meia-idade, com sobrepeso, pescoço curto, com alterações anatômicas das vias aéreas superiores. O diagnóstico definitivo é realizado por meio do estudo do sono através da polissonografia. Tratamento: O tratamento clínico inclui medidas comportamentais, como perda de peso, abstinência de álcool, sedativos, assim como o uso de dispositivos intra-orais removíveis ou pressão positiva contínua das vias aéreas (CPAP). Os tratamentos cirúrgicos visam aumentar o diâmetro das vias aéreas superiores e variam desde a uvulopalatofaringoplastia ao avanço maxilo-mandibular.

Introduction: Obstructive sleep apnea syndrome (OSAS) is a chronic disease that is progressive and impairing with high mortality and cardiovascular morbidity. OSAS affects 2-4% of the male population between 30 and69 years, and 1-2% of the female population in the same age range, thus constituting a public health problem. Physiopathology: OSAS occurs by association of physical disproportions, and an increase in complacency of this air passage. The musculature of upper airway (UA) passages relaxes during sleep, causing a reduction of UA dilating forces and repeated and intermediate episodes of obstruction. Each obstruction is accompanied by reduction in arterial oxygen saturation and the reaction of sleep interruption, causing repeated acute activation during sleep of the sympathetic autonomic nervous system with cardiorespiratory alterations that are already well-documented. Clinical Aspects: The symptoms of OSAS are nocturnal and occur at daytime as well. During sleep there is the presence of snoring, respiratory pauses, agitated sleep, multiple sleep interruptions and nocturia. While awake, the patient presents symptoms of excessive daytime somnolence and matinal headache, drop in intellectual function, depressive symptoms, sexual impotence and personality disorders. Typical OSAS patients are middle-aged overweight short-necked men with UA anatomical alterations. The definitive diagnosis is performed in the laboratory by means of a sleep study called Polysonography. Treatment: The clinical treatment includes behavioral measures such as weight loss and abstinence from alcohol and sedatives. Physical measures include the use of removable intra-oral devices or continuous positive airways pressure (CPAP). Surgical treatments aim at increasing UA and varies from Uvulopalatopharyngoplasty to maxillo-mandibular advance.

Structural characterization and distribution of elastic system fibers in the human prostate and some prostatic lesions

Prostatic disorders are accompanied by extensive but poorly understood modifications of the cells and surrounding extracellular matrix. In this study, we examined the distribution of the elastic system fibers in prostatic disorders compared to normal tissue. Sections of prostatic transurethral resections and/or radical prostatectomies were examined after staining with hematoxylin-eosin plus fluorescence microscopy and after Weigert's staining for elastic fibers. Transmission electron microscopy was used to examine the ultrastructure of tissues from radical prostatectomy. A concentric fibrous extracellular matrix and smooth muscle cells were observed surrounding normal acini. The elastic fibers were thin and inconspicuous. In benign prostatic hyperplasia (BPH) the elastic components were of variable thickness and formed a three-dimensional network at the base of the epithelium. Conversely, increased variability in the elastic fiber distribution was observed in adenocarcinomas, depending on the tumor grade. In adenocarcinomas with little differentiation, in some hyperplasic acini, and in the stroma adjacent to tumoral mass, ruptured and residual elastic fibers indicative of matrix degradation or remodeling were seen. In more undifferentiated tumors, a pre-elastic network, perhaps indicative of a new extracellular matrix microenvironment was seen. These results indicate that prostate cancer cell invasion involves extensive remodeling of the fibers of the elastic system.

Basic nuclear protein substituition during spermiogenesis in Hyla ranki (Amphibia, Anura, Hylidae

One of the most noticeable modifications observed during spermatic differentiation is the change in nuclear shape and especially chromatin condensation. This study was undertaken to determine nuclear modifications during spermiogenesis in Hyla ranki taking into account patterns of nuclear basophilia, nuclear condensation and elongation. Adult testes processed for light microscopy were stained with toluidine blue at PH 4.0, and those used for transmission electron microscopy were processed using the ethanolic phosphotungstic acid (E-PTA) method for basic proteins. Toluidine blue-treated material exhibited a different basophilic response as a function of the degree of cell maturation, the same variation occurring in relation to the nuclear density seen with the electron microscope. By using both staining methods, it is assumed that during cytodifferentiation of the spermatic cells of Hyla ranki, the high degree of chromation condensation is possibly related to the appearance of a protamine-like protein which substitutes somatic histones or associates to these, giving rise to a tighter DNA-protein complex.