Sauvagine/urotensin I-like immunoreactivity in the brain of the dogfish, Scyliorhinus canicula

The localization of a sauvagine (SV)/urotensin I (UI)-like material in the brain of the dogfish, Scyliorhinus canicula, was studied by immunohistochemical techniques, employing an antiserum raised in rabbit against synthetic SV which widely cross-reacts with UI. Positive cell bodies and nerve fibers were identified in the dorsocaudal hypothalamic region of the tuberculum posterius, in the nucleus sacci vasculosi and nucleus tuberculi posterioris. A dense network of immunoreactive axons was shown in the whole tuberculum posterius. These findings support the view that SV/UI-like peptides may be involved in neuromodulatory functions throughout the brain of cartilaginous fish.     

Auditory brainstem response in premenopausal women taking oral contraceptives

BACKGROUND: The aim of this prospective study was to evaluate the effects of the new monophasic oral contraceptives on the audiological system in premenopausal women. METHODS: The auditory brainstem response (ABR) was measured in 94 women during the follicular, periovular and luteal phases of one menstrual cycle in which ovulation was confirmed using sonography and serum progesterone concentration. The latencies for waves I, III and V were determined, and the inter-peak intervals were calculated for waves I-III, I-V and III-V. All 94 women began taking oral contraceptives: 23 women used 20 microg ethinyl estradiol (EE) plus 150 microg desogestrel, 24 women used 30 microg EE plus 75 microg gestodene, and 47 women used 15 microg EE plus 60 microg gestodene. During the third month of contraceptive intake, each subject was again tested for ABR, as above. RESULTS: The wave latencies and inter-peak intervals showed shorter values during the periovular phase with respect to the luteal phase (P < 0.05), the follicular phase for wave I and for inter-peak interval I-V (P < 0.05) of the menstrual cycle. All of the ABR results in pill users were statistically different from those of the periovular phase (P < 0.05), though similar to those of both the luteal and follicular phases (P = NS). CONCLUSIONS: ABR seems to depend on the variations of ovarian steroids during the menstrual cycle and during oral contraceptive intake.     

Phylogenetic study on distribution and chromogranin/secretogranin content of histamine immunoreactive elements in the gut

The distribution of histamine-immunoreactive (HA-IR) elements and possible coexistence of chromogranin A (CgA), chromogranin B (CgB) and secretogranin II (SgII) were immunohistochemically studied in gut specimens of various vertebrate species. In fish, HA-IR cells were distributed mainly within the gastric and duodenal mucosa, and nerve fibres in the gastric myenteric plexus. Only the gastric HA-IR cells co-stored SgII. In frog specimens, HA-IR endocrine cells and nerve fibres were found in the distal stomach wall, but SgII coexisted only in the nerve fibres. In lizard, HA-IR endocrine cells were widely distributed from the oesophagus to the small intestine, but only those in the stomach co-stored CgA, CgB and SgII. In chick, HA-IR cells were found in the proventriculus and almost all co-stored all three proteins. In rat, HA-IR cells were accumulated in the oxyntic mucosa and all of them constantly immunostained for CgA only.     

Colonic Cell Proliferation in Normal Mucosa of Patients with Colon Cancer

Cell kinetics parameters have been analysed in colonic mucosa at different distances from a tumour in patients with colon carcinoma. Total cell number (TCN), H thymidine labelling index (TLI), mitotic index (MI), Goblet cell index (GCI) and the distribution of labelled cells along the crypt column (cell position frequency plot) were determined in well-aligned crypts. Total cell number, GCI and the labelled cell position frequency plots were similar in different samples from the same individual. A negative linear correlation between TCN and TLI was observed. The analysis of the cell position plots showed two patterns 1) with a high concentration in the bottom fifth of the crypt and 2) with frequent labelled cells at high positions. Whereas a negative correlation between overall TLI and the percent contribution to the TLI of the lowermost fifth was seen, the correlation was positive for the next 3 fifths and labelling was absent in the last part of the crypt.     

Stated and actual management of acute myocardial infarction among different specialties

OBJECTIVES: To examine the variation in stated management of acute myocardial infarction (AMI) among clinicians of different specialties, and to compare stated with actual practice. DESIGN: Mail survey using a hypothetical case history, and review of medical records. SETTING: 47 public hospitals in New South Wales. SUBJECTS: 224 cardiologists, general/other physicians and general practitioners (GPs) who manage patients with AMI; 390 patients admitted for AMI between February and June 1996. OUTCOME MEASURES: Stated and actual use of treatments and investigations for AMI. RESULTS: Stated use of aspirin, thrombolysis and beta-blockers (95%-100%, 95%-100% and 80%-86%, respectively) was high in all three specialties. Cardiologists were significantly more likely than GPs to state use of heparin (87% v 57%; P < 0.001), ACE inhibitors (84% v 49%; P < 0.001) and echocardiography or gated pool heart scan (79% v 26%; P < 0.001). Stated use of nitrates by cardiologists was significantly lower compared with the other specialties (29% v 50% and 44%; P = 0.027). Actual use of aspirin was high (> 80%) in all specialties. Actual use of thrombolysis was similar to stated use after adjusting for factors such as time to hospital arrival and ST-segment elevation. There were substantial differences between stated and actual use. CONCLUSIONS: There were differences in practice patterns between and among clinicians of different specialties in NSW, consistent with findings from other countries. The high stated and actual use of aspirin and thrombolysis is encouraging.     

Critical appraisal of a non-coplanar technique for radiotherapy of breast minimising lung involvement.

BACKGROUND AND PURPOSE: To appraise the potential benefit of a conformal technique with non-coplanar fields to minimise lung irradiation in the radiation treatment of breast. PATIENTS AND METHODS: A comparative study was carried out at planning level for six patients selected for their inadequate sparing of healthy lung tissue with the reference tangential technique. Plans were designed for the conventional tangential technique, for an alternative conformal approach with three beams and for the newly proposed technique with two non-coplanar beams. RESULTS: In average for the new technique compared to the reference, mean lung dose dropped from approximately 16 to 10.5 Gy, V(20 Gy) from 29.5 to 18.2% and the dose delivered to 1/3 (1/4) of the lung volume dropped from 28.5% (67.3%) to 8.7% (13.4%). For PTV, the volume receiving at least 90% of the prescribed dose resulted 97.4% for the new and 97.3% for the reference. Conformity index improved significantly from 2.58 for the reference to 1.84 for the new technique. CONCLUSIONS: For a subgroup population of breast cancer patients, where conventional techniques failed to achieve high conformal avoidance, a treatment modality with non-coplanar beams was developed and clinically tested for six patients. It resulted dosimetrically adequate, particularly when the risk of toxicity is relevant.     

In vivo and in vitro effects of 42-hydroxy-palytoxin on mouse skeletal muscle: Structural and functional impairment

Palytoxins (PLTXs) are known seafood contaminants and their entrance into the food chain raises concern about possible effects on human health. The increasing number of analogs being identified in edible marine organisms complicates the estimation of the real hazard associated with the presence of PLTX-like compounds. So far, 42-OH-PLTX is one of the few congeners available, and the study of its toxicity represents an important step toward a better comprehension of the mechanism of action of this family of compounds. From this perspective, the aim of this work was to investigate the in vivo and in vitro effect of 42-OH-PLTX on skeletal muscle, one of the most sensitive targets for PLTXs. Our results demonstrate that 42-OH-PLTX causes damage at the skeletal muscle level with a cytotoxic potency similar to that of PLTX. 42-OH-PLTX induces cytotoxicity and cell swelling in a Na⁺-dependent manner similar to the parent compound. However, the limited Ca²⁺-dependence of the toxic insult induced by 42-OH-PLTX suggests a specific mechanism of action for this analog. Our results also suggest an impaired response to the physiological agonist acetylcholine and altered cell elasticity.