Surveillance of foodborne infections— the role of the Communicable Disease Surveillance Centre

The paper describes the work of the Public Health Laboratory Service, popularly referred to as “Colindale”, and reviews the types of infection which are commonly food or waterborne and their relative importance. Cholera, typhoid and paratyphoid are rare diseases usually acquired abroad. Bovine tuberculosis, brucellosis and foodborne helmenthiasis have been almost eliminated as indigenous diseases. However, salmonellosis and Campylobacter enteritis are increasing. The increase has not been satisfactorily explained but is probably due to bovine and poultry infections. Although most notified food poisoning incidents are due to salmonella, a number of other organisms have been implicated, the cause being defective food hygiene. Viral foodborne diseases, including hepatitis A, have been associated mainly with shellfish. The incidence of new foodborne infections may be increasing.     

Human cell membrane oxidative damage induced by single and fractionated doses of ionizing radiation: a fluorescence spectroscopy study

Purpose: To investigate the production and repair of lipid oxidative damage in two human cell lines exposed to acute and fractionated dose of ionizing radiation. Radiation dose was in the range from 0.1 to 44Gy. Materials and Methods: K562 and HL60 human cell lines have been used, 24 and 96 h after seeding. Membrane lipid oxidative damage has been detected by the measurement of the fluorescence decay of 1,6-diphenyl-1,3,5-hexatriene (DPH), its polarization value and the conjugated dienes concentration. The modification of DPH decay has been previously reported to be directly related to the lipid hydroperoxide concentration. Results: A modification of the DPH decay has been observed as a linear function of the logarithm of the radiation dose and only when the irradiation was performed in the presence of oxygen. The amount of the damage is related to the time after the cell medium change. By exposing the cells to fractionated radiation doses for several days (10 cGyday- 1), the oxidative damage has been found to be cumulative. After a single acute dose, evidence of repair of the lipid oxidative damage was not obtained. Conclusions: Following a previously developed method, the membrane damage was attributed to the production of hydroperoxide residues in the lipid acyl chains with the consequence of water penetration into the external portion of the bilayer, from the aqueous environment to the position of hydroperoxides. This damage is not repaired. The results obtained by measuring the DPH fluorescence decay have been compared with those obtained using other current optical and biochemical methods. None of these techniques could detect membrane oxidative damage at doses 10 Gy. Finally, the different sensitivity of 'young' and 'old' cells to the oxidative damage can be related to different cholesterol concentrations.     

SLEEP-WAKE PATTERNS AND INTEGRATED VALUES OF LUTEINIZING HORMONE, FOLLICLE STIMULATING HORMONE, PROLACTIN, GROWTH HORMONE AND THYROID STIMULATING HORMONE IN NORMAL AND CRYPTORCHID PUBERTAL PATIENTS

The sleep-wake behaviour of LH, FSH, PRI, GH and TSH was studied in seven cryptorchid patients (four unilateral and three bilateral cryptorchids) average age 12 years and in nine normal pubertal boys of 13 years (mean age). Blood samples were collected by a continuous withdrawal pump, every hour, for 24 h. The hormonal concentration for every fraction of time was measured and related to the sleep (Sc-), wake (Wc-) and total 24 h period (Dc-). The integrated concentrations of the corresponding periods (IS, IW, ID) were calculated as well as their ratios (IS/IW; IS/ID%). For GH and TSH, the data obtained demonstrated no differences between cryptorchid and pubertal subjects. The PRL secretion in cryptorchid patients was moderately increased during the hours of nocturnal sleep. A normal pubertal sleep-wake rhythm was found for gonadotrophins in both groups of subjects. More marked levels of LH secretion were observed in cryptorchid boys compared to normal pubertals. The presence of a sleep-wake rhythm was also found in the cryptorchid patients and normal pubertal subjects in the P 1 stage. These data suggest that the CNS "programme" which controls the onset of puberty may be normal in cryptorchid patients.     

Psychological status of men with haemophilia and HIV infection: two-year follow-up

This study aimed to assess the psychological status of men with haemophilia and HIV infection and to monitor changes in psychlogical status over time, in order to evaluate the need for psychological support. The study included 24 HIV seropositive men and a control group of 21 HIV seronegative men who attended the Haemophilia Centre in Bari (Italy). Subjects underwent psychological tests (STAl-Y: State and Trait Anxiety Inventory; SDS: Self-Rating Depression Scale) and completed a questionnaire on the emotional impact of AIDS. Assessment was repeated at 6-monthly intervals over a 2-year period. Contrary to expectation, HIV seronegative men with haemophilia had worse anxiety and depression scores, reported more confusion and fear, and had more reluctance towards the use of blood products (despite their present safety) than HIV seropositives. Possible reasons for these findings are considered, and their implications for clinical practice discussed.     

THE ROLE OF VASCULAR ENDOTHELIAL GROWTH FACTOR IN A MURINE CHRONIC GRANULOMATOUS TISSUE AIR POUCH MODEL OF ANGIOGENESIS

Chronic granulomatous inflammation may be considered an angiogenic-dependent process. Recently it has been demonstrated that vascular endothelial growth factor (VEGF) or vascular permeability factor is essential for tumour angiogenesis. Its role in inflammation-mediated angiogenesis has yet to be determined. In this study, the murine chronic granulomatous air pouch model was used to investigate the role of VEGF in angiogenesis. Animals were treated twice weekly with 10 μ g per animal of neutralizing antibody to rh VEGF and the vascularity and granuloma dry weight were assessed after 7 days. This resulted in significant suppression of both angiogenesis and granuloma dry weight. Western blot analysis demonstrated the presence of VEGF; the levels of protein paralleled the angiogenic response. These results demonstrate for the first time that VEGF may be an important regulator of angiogenesis in inflammation.     

Lack of effect of desmopressin on ACTH and cortisol responses to ovine corticotropin-releasing hormone in anorexia nervosa

Abstract. Both arginine vasopressin (AVP) and corticotropin-releasing hormone (CRH) are involved in the release of ACTH in man. Desmopressin (DDAVP), a synthetic analogue of AVP, has been shown to have a CRH-like action (able to promote ACTH and cortisol release) in animals but not in normal man. Nevertheless, DDAVP is able to release ACTH and cortisol in ACTH-dependent Cushing's disease. We studied eight anorexia nervosa (AN) patients [as AN is a condition in which chronic activation of the hypothalamic-pituitary-adrenal (HPA) axis is commonly reported] in a refeeding phase of the disease, to evaluate whether, after weight gain, ACTH and cortisol response to ovine corticotropin-releasing hormone (oCRH) [1 μg kg^-1 body weight (BW) i.v.] is restored. We also wanted to ascertain the effect on the HPA axis of 10 μg i.v. DDAVP alone and as pretreatment to oCRH (1 μg kg^-1 BW i.v.)-induced secretion of ACTH and cortisol. We studied six normal women as control subjects. No significant differences in ACTH and cortisol responses to oCRH were found between AN patients and control subjects. DDAVP was not able to stimulate ACTH or cortisol release in AN patients or in control subjects, but in the latter it was able to significantly enhance (P < 0.05) ACTH [area under curve (AUC): 590.0± 104.4 pmol L^-1 120 min^-1 and cortisol (AUC: 28899.0 ± 6935.2nmol L^-1 120 min^-1) responses to oCRH (ACTH AUC: 325.7 ± 101.7 pmol L^-1 120 min^-1, cortisol AUC: 14197.4 ± 2930.0 nmol L^-1 120 min^-1). The present data show that DDAVP does not stimulate ACTH and cortisol in AN patients or, as previously reported, in normal subjects. However, DDAVP is able to enhance ACTH and cortisol release after oCRH administration in normal subjects but not in AN patients. This finding could be due to a down-regulation of hypophyseal DDAVP V3 receptors in AN as a direct consequence of the hypercortisolaemic status usually present.     

A double-blind assessment of additive intolerance in children using a 12 day challenge period at home

Alleged food-additive intolerance (respiratory, dermatological, behavioural or abdominal) was assessed in 19 children using daily challenge drinks of either, base product alone, base product plus sunset yellow/tartrazine, or base product plus sodium metabisulphite/sodium benzoate. The same type of drink was given for 12 days, double-blind and in random order. During the trial the children were maintained on an additive-free diet under supervision. Diary cards were used to record symptoms and medication usage. If there was an apparent association between symptoms and drink ingredient the trial was repeated, again double-blind. Additive intolerance was confirmed by a consistent deterioration of symptoms in only three children. In one, urticaria was induced by the colourings, in another extremely abnormal behaviour was induced by the preservatives and a third child was only free of asthma and abdominal pain on placebo. This form of individual trial, using 12 daily drinks, overcomes some of the objections to a single challenge study. Despite this, intolerance to the additives was only confirmed in 3/19 children in whom it had been believed to occur.     

High Energy Transcatheter Cardioversion for Chronic, Poorly Tolerated Atrial Fibrillation

Between August 1991 and May 1993, 14 patients affected by chronic, poorly tolerated atrial fibrillation (AF) were submitted to high energy transcatheter Cardioversion. Mean duration of AF was 27.4 ± 45.1 months. In nine patients (56%), AF lasted for > 1 year. All patients had underlying heart disease, with a mean LVEF of 45.2%± 11.8% and a NYHA Class ≥ II. Previously, a mean of 2.9 ± 1.3 patients failed external electrical Cardioversion, with and without antiarrhythmics, have been attempted. Transcatheter conversion was performed by pulling the His-bundle catheter back in the right atrial cavity until no His bundle activity was recorded on distal poles, and then delivering the shock between a proximal electrode (cathode) and a back plate (anode). In all patients, transcatheter conversion restored sinus rhythm. Transient complete atrioventricular (AV) block was observed in four patients (28%), and treated by prophylactic temporary pacing. At 1 year, seven patients (50%) were still in sinus rhythm. In this series, only younger age could be related to AF recurrence (46.1 ± 10.8 vs 63.4 ± 6.8 years, P ≤ 0.004), even if prophylaxis with amiodarone showed a positive trend versus sinus rhythm maintenance (71 % vs 14%, P = NS). In conclusion, high energy transcatheter Cardioversion is a safe and effective method of restoring sinus rhythm in patients with chronic, poorly tolerated AF. In these patients, high energy transcatheter Cardioversion could be considered as an alternative to AV node ablation techniques, avoiding pacemaker implant and embolic risk. Larger studies are needed to determine better patient selection and delineate drug strategy after the procedure.