Nonpalpable cancer of the prostate: assessment with transrectal US

Palpable cancer of the prostate is widely believed to be clinically significant. The authors compared the clinical significance of palpable prostate cancer with nonpalpable prostate cancer discovered with transrectal ultrasound (US). A strong association between lesion volume measured with preoperative transrectal US and volumetric measurements in 60 radical prostatectomy specimens permitted the use of tumor size measured with transrectal US as a reasonable estimation of gross tumor volume. In a subsequent clinical series, 147 biopsy-proved cancers were grouped according to size measured at US, the findings at digital rectal examination (DRE), and the Gleason score. For the 147 patients with known prostate cancer, a statistically significant difference between Gleason scores of palpable and nonpalpable cancers could not be demonstrated when the size of the tumor and its location within the prostate were held constant. Assuming that the Gleason score is a reliable indication of malignant potential and clinical significance, the authors conclude that nonpalpable prostatic cancer detected with transrectal US alone may be just as clinically significant as prostatic cancer discovered with DRE.     

Reversible ureteric and pelvicalyceal calcification in a 12-year-old boy

A 12-year-old boy was shown on CT to have unexplained pelvicalyceal and ureteric calcification which resolved over a 16-month period. Received: 10 August 1998 Accepted: 30 November 1998     

Micropulse diode laser photocoagulation for central serous chorio-retinopathy

Purpose:  Central serous chorioretinopathy (CSC) is usually characterized by a localized detachment of the neurosensory retina that is self-limiting. However, some cases may persist or recur leading to degenerative changes of the retinal pigment epithelium and the neurosensory retina resulting in severe visual loss and requiring intervention.
Methods:  This retrospective case series reports the long-term visual outcome of the use of micropulse laser photocoagulation for this condition with a review of literature.
Results:  The mean follow up was 17.1 months. Four of the five patients had complete resolution of symptoms whereas one patient had recurrent CSC from a new leak that failed to resolve after repeat micropulse treatment despite improvement in symptoms.
Discussion:  The outcomes in this case series confirm the long-term efficacy of micropulse laser in the management of CSC. It produces therapeutic effects that appear comparable to those of conventional photocoagulation with no detectable signs of laser-induced iatrogenic damage.     

Uses and abuses of a biosynthetic dressing for partial skin thickness burns

The following report reviews 851 applications of Biobrane on partial skin thickness burn wounds awaiting epithelialization. After the patients had been evaluated and resuscitated as needed, the burn wounds were cleansed and debrided. Those evaluated as shallow were treated with Biobrane application. Joint surfaces were splinted for immobilization. The wound was inspected at 24 and 48 h and if any fluid had accumulated it was aspirated and the wound was redressed. When the Biobrane was adherent, the wound was covered with a light dressing and joint immobilization was discontinued. Treatment with Biobrane dressing provided certain advantages over other topical wound care. As the dressing changes were performed less frequently outpatient care was possible, with a resultant decrease in both the length of hospital stay and the ultimate cost of burn care. Wound desiccation is prevented and pain is decreased. Accurate diagnosis of wound depth is crucial if Biobrane is to be used. Very deep wounds will not allow Biobrane adherence, neither will it occur if the wound has a high bacterial count. If joint surfaces are not splinted, the Biobrane will shear and not adhere to the wound. Convex and concave surfaces can be treated with Biobrane, which may need to be meshed.     

Evaluation of tumour promoting potency of fish borne toxaphene residues, as compared to technical toxaphene and UV-irradiated toxaphene

In this study the potential impact of food chain-based biotransformation and physico-chemical weathering of toxaphene on its tumour promoting potential was investigated in vitro and in vivo. Human exposure to toxaphene is mainly through consumption of contaminated fish, therefore fish-borne residues of toxaphene (cod liver extract, CLE) were prepared by exposing cod to technical toxaphene (TT) for 63 days. UV-irradiated toxaphene (uvT) was included to represent a physico-chemical weathered toxaphene mixture. In vitro, TT, uvT and CLE all showed a dose- and time-dependent inhibition of gap junctional intercellular communication (GJIC) with a relative potency of CLE>TT=uvT. Tumour promoting potency was further studied in vivo in a medium term two-stage initiation/promotion bioassay in female Sprague-Dawley rats, using an increase in altered hepatic foci positive for glutathione-S-transferase-P (AHF-GST-P) as read out. No increase in AHF-GST-P occurred following exposure to either TT, uvT, or CLE, except for the positive control group (2,3,7,8-TCDD). Based on this study the no observed adverse effect level (NOAEL) for tumour promoting potency is at least 12.5mg/kg/week, or higher for CLE. Considering current human exposure levels in Europe it is doubtful that consumption of fish at current levels of toxaphene contamination give rise to human health risk.     

Bi-affinity alpha 1-adrenoceptor binding in normal rat brain in vivo.

The specific binding in rat brain in vivo of [125I]HEAT ([125I]iodo-2-[beta-(4-hydroxyphenyl)ethylamino methyl), a selective alpha 1-adrenoceptor ligand, was analyzed by a method designed to distinguish sites with different affinities. The data indicate at least two sites with different affinities for the alpha 1-adrenoreceptor in normal rat brain in vivo: a high-affinity site with Kd (half-saturation constant) of 3.6 +/- 0.7 nM (AV +/- SD), and a low-affinity site with Kd of 668 +/- 552 nM. The density (Bmax) of the high-affinity site in nine brain regions--auditory, visual, sensorimotor (four layers) and frontal cortex and lateral thalamic and medial geniculate nuclei--varied from 2.2 +/- 0.8 to 14.6 +/- 0.6 pmole/g, while the low-affinity range was 149 +/- 44 to 577 +/- 30 pmole/g. The results also revealed a very dynamic relationship between the two sites regulated by the concentration of the ligand ranging from 80% preponderance of the high-affinity sites at low ligand concentrations to more than 95% preponderance of the low-affinity sites at high ligand concentrations.