A Novel Nomogram to Identify Candidates for Extended Pelvic Lymph Node Dissection Among Patients with Clinically Localized Prostate Cancer Diagnosed with Magnetic Resonance Imaging-targeted and Systematic Biopsies

Background

Available models for predicting lymph node invasion (LNI) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP) might not be applicable to men diagnosed via magnetic resonance imaging (MRI)-targeted biopsies.

Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography

The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.     

The aging process and potential interventions to extend life expectancy

Aging is commonly defined as the accumulation of diverse deleterious changes occurring in cells and tissues with advancing age that are responsible for the increased risk of disease and death. The major theories of aging are all specific of a particular cause of aging, providing useful and important insights for the understanding of age-related physiological changes. However, a global view of them is needed when debating of a process which is still obscure in some of its aspects. In this context, the search for a single cause of aging has recently been replaced by the view of aging as an extremely complex, multifactorial process. Therefore, the different theories of aging should not be considered as mutually exclusive, but complementary of others in the explanation of some or all the features of the normal aging process. To date, no convincing evidence showing the administration of existing “anti-aging” remedies can slow aging or increase longevity in humans is available. Nevertheless, several studies on animal models have shown that aging rates and life expectancy can be modified. The present review provides an overlook of the most commonly accepted theories of aging, providing current evidence of those interventions aimed at modifying the aging process.     

Small-cell neuroendocrine carcinoma of the ampullary region. A clinicopathologic, immunohistochemical, and ultrastructural study of three cases.

We report the clinicopathologic, immunohistochemical, and ultrastructural features of three small-cell neuroendocrine carcinomas of the ampullary region of the duodenum. All patients were men; their ages were 51, 62, and 66 years. The therapy consisted of pancreatoduodenectomy. All patients died of the disease; median survival was 10 months from the diagnosis. The histological appearance was identical to pulmonary and extrapulmonary small-cell carcinoma. The neuroendocrine differentiation was demonstrated ultrastructurally by the presence of dense-core granules, and by the positive immunoreaction for neuron-specific enolase and Leu-7 in each case. One case expressed a focal positivity for chromogranin A (PHE-5) and argyrophilic granules. The same case showed the presence of neurofilaments on frozen material. Neurofilament proteins could not be demonstrated in any case in paraffin sections. Neoplastic cells exhibited cytoplasmic immunostaining for cytokeratins (CAM 5.2) in all cases. In one case, a large number of neoplastic cells (60-70%) exhibited nuclear Ki-67 positivity. We postulate that the disease's histogenesis was from epithelial stem cell expressing both epithelial and neuroendocrine characteristics. The clinical behavior of small-cell neuroendocrine carcinomas of the ampullary region appears to be extremely aggressive, with early metastases and fatal outcome.     

Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials

BACKGROUND: In general practice, acute sinusitis is frequently diagnosed and treated with antibiotics. OBJECTIVE: This study aimed to determine the evidence for the effectiveness of antibiotic treatment in acute maxillary sinusitis in adults by assessing the methodological quality of placebo-controlled double-blind randomized trials. METHOD: An evaluation by four raters through a 35-item scoring-scale for internal and external validity of all placebo-controlled double-blind randomized trials on acute sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five trials were excluded because they were not placebo-controlled, double-blind, randomized, or were carried out in patients with chronic sinusitis or in children. The three remaining trials were performed in different populations (one in general practice) between 1973 and 1978. Only one study claimed superiority of antibiotic treatment. Different inclusion criteria and major outcome measures were used by the authors. The reliability of major outcome events was reported poorly or not at all and in two studies outcome measures were clinically inappropriate. The studies scored 30-62% of the maximum attainable score for internal validity and 10-20% for external validity. CONCLUSION: The effectiveness of antibiotic treatment in acute maxillary sinusitis in a general practice population is not based sufficiently on evidence.      

The effect of hyperbaric oxygen on reperfusion of ischemic axial skin flaps: a laser Doppler analysis.

This study evaluates the microvascular reperfusion of ischemic skin flaps with and without acute hyperbaric oxygen (HBO) treatment. Thirty-two axial pattern epigastric skin flaps (3 x 6 cm) in male Wistar rats were subjected to 8 hours of global ischemia by pedicle clamp occlusion. The rats were divided into the following control and two experimental groups: Control (n = 12) with ischemia, no HBO; Group 1 (n = 11) with HBO treatment (three 1.75-hour dives, 2.5 absolute atm, 100% O2) during ischemia; and Group 2 (n = 9) with HBO treatment (two 1.75-hour dives) immediately after ischemia. Laser Doppler flows were recorded in two distal standardized flap locations at 0.5, 2, 4, and 18 hours after reperfusion in control rats and Group 1 rats and at 18 hours only in Group 2 rats, using a Med-Pacific 6000 laser Doppler unit. Mean distal flap laser Doppler flows (mV) were Control: 0.5 hours = 23.2 +/- 11.9, 2 hours = 52.8 +/- 27.3, 4 hours = 53.6 +/- 32.1, 18 hours = 40.2 +/- 36.2; Group 1: 0.5 hours = 71.8 +/- 30.9 (p less than 0.05 vs. control), 2 hours = 74.3 +/- 27.3, 4 hours = 67.4 +/- 20.6, 18 hours = 79.1 +/- 40.3 (p less than 0.05 vs. control); and Group 2: 18 hours = 90.3 +/- 47.9 (p less than 0.05 vs. control). It is concluded that acute HBO treatment of ischemic rat skin flaps improves distal microvascular perfusion as measured by laser Doppler flowmetry. This effect is observed for HBO treatment given either during or immediately after prolonged global ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Sonography detection of small intra-abdominal fat variations.

The aim of this study was to check the reliability of sonography in measuring small variations in quantities of subcutaneous and intra-abdominal fat. Twenty-six obese women (BMI 39 +/- 6) underwent a 15 day very low calorie diet. The study included, both before and after very low calorie diet, computed tomography measurements of total (AT), visceral (VAT) and subcutaneous (SAT) adipose tissue areas, visceral/subcutaneous area ratio (V/S), waist/hip circumference ratio measurements (W/H), and ultrasound measurements of abdominal subcutaneous skin-muscle thickness, intra-abdominal muscle-aorta thickness and intra-abdominal/subcutaneous thickness ratio. Weight reduction was from 101 +/- 17 to 95 +/- 16 kg (P less than 0.001). W/H dropped from 0.83 +/- 0.06 to 0.82 +/- 0.07 (n.s.). VAT dropped from 158 +/- 72 to 134 +/- 61 cm2 (P less than 0.005), SAT from 572 +/- 151 to 566 +/- 164 cm2 (n.s.) and V/S from 0.29 +/- 0.15 to 0.25 +/- 0.11 (P less than 0.01). Abdominal subcutaneous fat thickness decreased from 36 +/- 8 to 35 +/- 10 mm (n.s.), intra-abdominal thickness from 39 +/- 25 to 20 +/- 20 mm (P less than 0.001) and intra-abdominal/subcutaneous from 1.1 +/- 0.7 to 0.8 +/- 0.6 (P less than 0.005). VAT measurement accurately identified small intra-abdominal fat variations. W/H could not evaluate visceral fat loss, because of simultaneous decreases in waist and hip circumferences. Ultrasound was able to measure small reductions in intra-abdominal fat.     

Kinetic parameters of tyrosine hydroxylase in the rat's preoptic region during sleep deprivation and recovery induced by ambient temperature

The role of catecholaminergic mechanisms in determining the changes in the rat's preoptic cyclic adenosine monophosphate (cAMP) concentration during sleep deprivation and recovery induced by ambient temperature was investigated in the present study. To this end, the activity of tyrosine hydroxylase, the rate-limiting enzyme in catecholamine biosynthesis, was measured in the preoptic region of rats maintained in: (a) control (22 degrees C for 52 h), (b) deprivation (-10 degrees C for 52 h), and (c) recovery (22 degrees C for 4 h after 48 h at -10 degrees C) conditions. The enzyme followed a Michaelis-Menten kinetic. The analysis of substrate-related kinetic parameters (Km and Vmax) did not show any clear-cut difference between experimental conditions, which, as already known, induce both sleep deprivation and recovery in relation to significant cAMP changes.