[Electron microscopic studies of the action of erythromycin, doxycycline and ofloxacin on the growth cycle of Chlamydia trachomatis]

The aim of this work is to realise an ultra structural study of the action of antibiotics (doxycycline, erythromycin and ofloxacin) on the intracellular growth cycle of chlamydia. All assays were done on McCoy cells. Antibiotics were added to the culture medium two hours after inoculation with C. trachomatis. 24 and 48 hours, cells were removed and treated by standard procedure for transmission electron microscopy. No difference between control-cells and cells treated with doxycycline, erythromycin (0.015 mg/l) and ofloxacin (0.15 mg/l), was observed in the inclusions (number and size). However 48 hours, the quantity of elementary bodies (E.B.) was lower in treated culture. The organisms were not morphologically different from those seen in untreated culture. At higher concentrations of doxycycline and erythromycin (0.03 mg/l - 0.06 mg/l), the inclusions were smaller. Reticulate bodies (RB) were each in separate inclusion indicating that no fission has taken place. At 48 hours, no infectious forms (EB) were observed. Small or large RBs appeared with an apparent normal cytoplasmic membrane within an inflated cell wall. With ofloxacin (0.3 - 0.6 mg/l), inclusions contained enlarged and sometimes empty bacterial cells. Doxycycline and erythromycin (0.03 mg/l) inhibit the division of RBs and there maturation to EBs Ofloxacin (0.3 mg/l) induces the production of large abnormal forms which may not be able to revert towards viable bacteria.

Prospective study of risk factors in natural rubber latex hypersensitivity

Five hundred sixty-nine subjects routinely underwent skin prick tests for latent sensitization to latex. The study of risk factors included skin tests to inhalant allergens, to diagnose atopy, and a questionnaire aimed at revealing frequent exposure to latex such as the wearing of gloves, multiple surgical procedures, or urinary catheterization. The subjects were categorized into five groups: group I, subjects with no risk factor (n = 272); group II, nonatopic subjects exposed to latex (n = 73); group III, atopic subjects not exposed (n = 180); group IV, exposed atopic subjects (n = 44); and group V, subjects with a history of intraoperative anaphylactic shock caused by latex (n = 13). Twenty-five subjects had spina bifida and were in either group II (14 subjects) or group IV (11 subjects). The questionnaire identified a probable allergy to latex in 18 subjects: 16 cases were confirmed by skin test, but responses were not informative in 23 patients who were sensitive to latex. Positive prick tests to latex were obtained in 0.37% of group I, 6.85% of group II, 9.44% of group III, and 36.36% of group IV. Of the children with spina bifida, 32% had positive skin test results. As risk factors, atopy and exposure were synergistic. We recommend predictive prick tests not only in children with spina bifida but also in any atopic subject or in any patient with a history of frequent exposure to latex. Latex could be considered a habitual allergen. The use of latex urinary catheters should be avoided in patients who are catheterized on a daily basis.

Effect of a series of 1-alkyl ether lipids on inhibition of phospholipase A2 activity and PAF responses

Several 1-alkyl ether lipids were studied for their ability to inhibit PLA2 and antagonize PAF responses. Studies with synthetic micellar substrate (1-stearyl-2-arachidonyl phosphocholine), at concentrations ranging from 0.02 to 1000 microM, demonstrate that CL 118326 inhibits porcine pancreatic PLA2 in vitro. As the substrate concentration increases, there is a dose-dependent increase in the IC50 value (IC50 ranges: 1.6-84.6 micrograms/ml or 2.6-137 microM). CL 118326 inhibits mammalian pancreatic PLA2, but not snake or bee venom PLA2. CL 118326 inhibits thrombin (IC50 = 7.9 microM), but not Na arachidonate- (IC50 > 100 microM) induced platelet aggregation, indicative of inhibition of cellular PLA2. CL 118326 inhibits other PLA2-dependent processes such as antigen-induced leukotriene (LTC4) release (IC50 = 2.3 micrograms/ml or 3.8 microM) and histamine release (IC50 = 1.4 micrograms/ml or 2.2 microM) in basophil-enriched WBCs. Intradermal coinjection of CL 118326 (10 micrograms) with PLA2 into guinea pig skin inhibits pancreatic PLA2-induced increase in vascular permeability and leakage, but not snake or bee venom PLA2-induced leakage. CL 118326 shows no PAF-like agonist activity in stimulating rabbit platelet-rich plasma. It inhibits PAF-induced aggregation (IC50 = 5.8 microM), but not ADP-induced aggregation. CL 118326 has greater efficacy as a PLA2 inhibitor than as a PAF antagonist since the IC50-substrate concentration ratio for PLA2 inhibition is < or = 1.0 at substrate concentrations of 10-1000 microM while the IC50-agonist ratio for PAF antagonism is > 100. Results for four other compounds related to CL 118326 are also presented.

[Severe anaphylactic shock with heart arrest caused by coffee and gum arabic, potentiated by beta-blocking eyedrops]

The case of a male patient who experienced four allergic accidents after drinking coffee is reported. Two serious anaphylactic reactions with cardiac arrest occurred after a continuous treatment with beta-blocking eye drops (timolol) was prescribed. Dual sensitivation to coffee and to the gum arabic coating roasted coffee beans was demonstrated by skin prick tests and by human basophil degranulation tests. Occupational allergy to green coffee has been widely described, but food sensitization to these two allergens has not yet been reported. This case also draws attention to the risk, inherent in beta-blockers, of immuno-allergic reactions. These drugs produce a loss of compensatory cardiovascular mechanisms and make those who take them resistant to the conventional treatment of anaphylactic shocks, which explains the serious accidents that occurred in this patient. The authors stress the usefulness of a thorough investigation for food allergy to a rare allergen in patients with idiopathic anaphylaxis.

Somatostatin inhibits the activity of adenylate cyclase in cultured human meningioma cells and stimulates their growth

It has been reported previously that most human meningiomas have receptors for somatostatin. Here we report the results of investigations of the effect of somatostatin and the somatostatin analog octreotide on the growth in vitro of human meningioma cells. Neither somatostatin nor its analog showed a direct growth inhibitory action on cultured human meningioma cells. Rather, there was a slight but significant stimulation of growth in the presence of somatostatin. The somatostatin receptors in meningioma tissue were shown to be functional since somatostatin inhibited forskolin-stimulated formation of cAMP by meningioma membranes. In addition, cAMP inhibited the growth of cultured meningioma cells. We conclude that the stimulation by somatostatin of the growth of human meningioma cells in vitro is caused by its inhibitory effect on cAMP formation. These results suggest that therapeutic trials of patients with (recurrent) inoperable meningiomas with somatostatin analogs have to be carried out with great caution.

[Study of cells harvested in nasal secretions after lavage. Improvement of the cytologic technique and application to ORL and bronchial pathology]

The study of the cells found in the nasal lavage fluid is now a very used method. It has many advantages and it is better than the study of nasal smears obtained by nose blowing and/or swabbing. In this work, we have studied the nasal cytology of patients with a nasal or bronchial pathology. A count of inflammatory cells in a hemocytometer is performed in 301 noses then the percentage of various cell types (eosinophils, lymphocytes and neutrophils) is performed on a glass slide stained by May Grunwald Giemsa. The results are correlated with the literature. The patients with a known NARES have a mean nasal eosinophilia of 26.8%; in the allergic rhinitis, the eosinophilia is 41.4%; the patients with a Fernand Widal Syndrome or with a nasosinusal polyposis have respectively a eosinophil percentage of 24.2% and 18.8%.

Selection and acquisition of audiovisual materials by health professionals

Audiovisual (AV) materials are widely used in the education of health professionals, and health science educators are usually the people who select audiovisual teaching materials. However, little is known about the selection process and there are few parameters that can be used for guidance. No previous research was uncovered that documented the selection/acquisition of materials by users. This paper reports a survey of health science educators and resource consultants at forty-five academic health centers in the United States, on their experiences in identifying, selecting, and using AV materials. The results provide a baseline of information on which future research can build.

Modifications of the thymus and splenic thymic dependent zones after in utero exposure to phenytoin: qualitative and quantitative analysis in C3H mice

Pregnant female mice were randomly distributed in two groups and received twice a day by gavage either 25 mg/kg Dilantin in 0.2 ml distilled water or 0.2 ml distilled water till full term. The offspring were sacrificed on day 5. In the exposed group, the thymic cortex was reduced with a low mitotic activity in the lymphoid population while reticuloepithelial tissue was enlarged; numerous interdigitated reticular cells accumulate at the cortico/medulla border. In the spleen, the white pulp was enlarged because of lymphocytes accumulation in the periarteriolar sheets. In these two organs, the relative number of Thyl-2+, Lyt 1+ and Lyt 2+ T cell subsets were also modified showing especially a decrease in the thymus and an increase in the spleen of the Lyt 1+ cells. Since at the same time the thymus and the spleen of the females which reproduced the neonates are quite unchanged, it is concluded that the developing immune system of the fetal mouse is more susceptible to diphenylhydantoin than the immune system of the adult. This raises the question of the reversibility of this in utero acquired immune impairment.

Autonomic dysfunction in perennial vasomotor rhinitis and the effect of mequitazine

Thirty patients with perennial vasomotor rhinitis were submitted to pharmacological tests to assess the autonomic responsiveness of extra-nasal and intra-nasal receptors to isoprenaline and phenylephrine by infusion, and to evaluate the effect of 14-days' treatment with mequitazine (5 mg twice daily) and placebo on clinical symptoms and on autonomic sensitivity. Isoprenaline induced a similar tachycardia in all patients, more pronounced than that observed in normal subjects, at the different times of testing, and also an increase in nasal resistance. With phenylephrine, marked bradycardia was observed, reflecting high vagal baroreflex sensitivity, and a transient decrease in nasal resistance was obtained. Mequitazine improved significantly the clinical symptoms but did not modify the autonomic receptivity. It is suggested that in patients with vasomotor rhinitis an autonomic dysfunction may play a role in a predisposing factor in nasal hyperreactivity with non-specific histamine release.

Vagal sensitivity in intrinsic and allergic asthma

In 20 intrinsic and 25 allergic asthmatic patients with active disease, vagal baroreflex sensitivity was assessed by use of the phenylephrine test, and vagal blockade effects on airways were measured by the response to intravenous atropine. For a given phenylephrine-induced increase in blood pressure, bradycardia was more marked in patients with intrinsic asthma than in those with allergic asthma. Intravenous atropine caused a similar spirometric improvement in both groups. It is suggested that: 1) an inverse relationship exists between vagal sensitivity and the allergic state in asthma; 2) antigenic related stimulation modulated by a low vagal tone and non-antigenic related stimuli with high tone modulation result in similar cholinergic discharges.

Interventricular fibroma and cystic renal dysplasia in a newborn

A newborn twin presented with a cardiac tumor; at autopsy microcystic dysplasia was found in the kidneys. The histology of the renal cysts were not unlike those found in many multisystem syndromes (e.g., Schwartz-Jampel, Ehlers-Danlos, and Jeune's asphyxiating thoracic dystrophy). No evidence of tuberous sclerosis or other phakomatoses were found. This case may alert other observers to carefully look for cystic dysplasia of the kidneys or other organs in association with cardiac tumors.