Quantitative functional outcomes of the conservative management of partial segmental thrombosis of the corpus cavernosum.

The low incidence of partial segmental thrombosis of the corpus cavernosum (PSTCC) means its management is guided by isolated case reports. Erectile function is an important outcome that has not been described quantitatively in the literature. We present two cases of PSTCC managed conservatively. Although both patients reported resolution of local symptoms, formal analysis of sexual function at follow-up review has revealed that only one achieved complete recovery.

Aetiology and treatment of symptomatic idiopathic urethral strictures in children.

OBJECTIVE: To report the presentation and treatment outcomes on a series of 12 paediatric bulbar or posterior urethral strictures that were possibly congenital in origin, identified in a 9-year period. METHODS: A retrospective case-note review of all cases of urethral strictures thought to be congenital in origin, prospectively collected into the departmental database. RESULTS: The age at presentation had a bimodal distribution with 6/12 presenting in the first year of life of which four had antenatal hydronephrosis and 5/12 presenting after the age of 11 years. All six patients under 1-year old had a successful outcome following urethrotomy and urethral dilatation. Four of five over 11 years of age ultimately required an urethroplasty and one 3-year-old may well require an urethroplasty in the future. CONCLUSION: This outcome, in conjunction with the bimodal age distribution at presentation, would suggest a different aetiology in older children, and we would urge caution in classifying strictures in ambulant children as genuinely congenital, as this population may represent the long-term manifestation of unrecorded bulbar urethral trauma or asymptomatic inflammation. Optical urethrotomy or dilatation is durable when treated in infancy, but older patients do not experience prolonged resolution and we would recommend treatment along adult lines for these.

The outcome of drug smuggling by 'body packers'--the British experience.

Body packing or internal concealment used by drug dealers to smuggle illicit substances, puts the body packer at risk of both imprisonment and death. We report our experience over a 4 year period from January 1996 to December 1999 of suspects presenting to our hospital (the largest series in Europe). A total of 572 cases were assessed radiographically and 180 were shown to be carrying foreign bodies. The commonest reasons for admission were suspected overdose or gastrointestinal obstruction. Thirty-six cases were admitted, of whom 7 required surgical intervention. No deaths occurred. Of all people detained for smuggling by internal concealment into Britain during this period, 27% were seen in our hospital. These cases may present alone or escorted by Her Majesty's Customs and Excise personnel, and one must be aware of this possibility even when situated away from a port of entry.

Capillary electrophoresis and capillary electrophoresis-electrospray-mass spectroscopy for the analysis of heterocyclic amines.

Fourteen heterocyclic amines (HAs) were analyzed by capillary electrophoresis (CE) on a polyvinyl alcohol (PVA)-coated capillary column. The optimized electrolyte is composed of 20 mM ammonium acetate, pH 3.0, and 20% methanol. Similar conditions were applied in electrospray-mass spectrometry (CE-ES-MS). The CE-ES-MS optimization procedure includes the position of the capillary in the stainless steel interface, the flow of the sheath liquid and its composition.

On the time course of surgically induced compensatory muscle hypertrophication of the rat plantaris muscle.

1. The time course of the hypertrophy and hyperplasia of the rat plantaris muscle was determined from measurements of total muscle mass and cross-section analysis of fixed muscle. 2. Muscle enlargement was induced by the surgical removal of the plantaris synergist muscles, the gastrocnemius and the soleus. 3. From the date of surgery through the third post-operative week, muscle enlargement is due to fiber hypertrophication (approximately 100% increase in diameter). After post-operative week three, muscle enlargement is due to a combination of hyperplasia and hypertrophy. At week four the cross-sectional areas return to control values. 4. The neuromuscular junction area was determined by measuring Karnovsky stained post-synaptic membrane. Only a modest 10-30% increase was noted at weeks 2 and 3 with a return to control levels at week 4. The differences were not statistically different.

Pre- and postsynaptic actions of valproic acid at the frog neuromuscular junction.

The effect of valproic acid (VPA) on synaptic transmission was investigated at the frog neuromuscular junction using electrophysiological methods. The drug caused a dose-dependent decrease in the quantal content of the endplate potential (EPP) and a significant reduction in the input resistance of the postjunctional membrane. There were no apparent changes in the resting membrane potential or the frequency of the miniature endplate potential (MEPP). These results suggest that VPA has pre- as well as postsynaptic actions, both of which could lead to suppression of synaptic transmission.

Voltage clamp analysis of inhibitory synaptic action in crayfish stretch receptor neurons.

Abdominal stretch receptor neurons of Procambarus clarkii were voltage clamped with two microelectrodes, and the synaptic currents set up by stimulating the inhibitory axons, or by rapid bath application of gamma-aminobutyric acid (GABA), were recorded. The inhibitory postsynaptic current (IPSC) decay was exponential, the time constant of decay being increased by membrane depolarization. The IPSC decay was prolonged by diphenylhydantoin, whereas the IPSC amplitude was depressed by picrotoxin. It is suggested that these effects may reflect slowing of the channel closing and opening rates, respectively. Step clamps applied in the presence of GABA yield currents that show inactivation in the 100 ms time range. This inactivation was shown to reflect chloride movement across the membrane. Step clamp data were used to construct dose-response curves. Diphenylhydantoin shifts the dose-response curve to the left with little change in the maximum response. Picrotoxin shifts the curve to the right with a small reduction in the maximum response. These effects are consistent with the postulated effects on channel opening and closing rates, if GABA normally opens a large portion of the channels. Suitable combinations of picrotoxin and diphenylhydantoin acting together leave the dose-response curve unmodified, as predicted.

A yeast mutant which accumulates precursor tRNAs.

It has been proposed that the conditional yeast mutant ts136 is defective in the transport of mRNA from the nucleus to the cytoplasm (Hutchinson, Hartwell and McLaughlin, 1969). We have examined ts136 to determine whether it is defective in tRNA biosynthesis. At the restrictive temperature, the mutant accumulates twelve new species of RNA. These species co-migrate on polyacrylamide gels with some of the pulse-labeled precursor tRNAs. Three of the new RNAs (species 1a, 1b and 1c are large enough to contain two tandom tRNAs. Although RNAs 1a, 1b, and 1c do not contain detectable levels of modified and methylated bases, at least one of them hybridizes to DNA from an E. coli plasmid containing a yeast tRNA gene. All the remaining RNAs (2--8) contain modified and methylated bases typical of tRNA. Three of these species were tested and were found to hybridize to tRNA genes. Ribosomal RNA synthesis is also defective in ts136. It is suggested that ts136 may be defective in a nucleolytic activity, which is a prerequisite to RNA transport.

The effect of guanidine on transmitter release in the ciliary ganglion of the chick.

1. The effect of guanidine hydrochloride on synaptic transmission at the chick ciliary ganglion was studied. 2. In bathing solution containing low calcium concentrations, guanidine produced a dose-dependent increase in the number of quanta released by the presynaptic action potential. No post-synaptic effects were observed. 3. Intracellular presynaptic recordings and monitoring of the presynaptic action potential post-synaptically via the coupling potential showed that the action of guanidine was independent of any alterations in the presynaptic spike.