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A revised formulation of the image light distribution of an incoherent line source proposed by Steel [Rev. Opt. 31, 334-340 (1952)] is presented. Analytical and numerical results based on this new representation are given. We explicitly show that a major error in Steel's final expression generates singularities, thereby preventing convenient numerical computation.

The role of Helicobacter pylori in generating of the chronic gastritis and in the maintaining of the gastroduodenal ulcerous disease, has been a major medical discovery of these past years in human gastroenterology. More recently in Man, studies have showed that the gastric tumours (adenocarcinoma, lymphoma) are epidemiologically associated with the H. pylori infection. Although the H. pylori infection is the one of the most frequent in the word, the epidemiologic and ecologic aspects of this infections are still not very well known. Thanks to phylogenic studies using the new molecular biology techniques and to fundamental experimental studies, we know more about helicobacteria in domestic carnivores as well as their morphologic characteristic, their taxonomia and more importantly details concerning their ecological niche. Few clinical studies have been made to this day, but the ones that have been undertaken are interesting in confirming the extensive prevalence of Helicobacter infections in domestic carnivores and in underlining their role in the genesis of the inflammatory gastropathies observed in these species. Recent observations have demonstrated the ubiquitous character of these helicobacteria by showing their presence in the stomach of man, dogs and cats. This ubiquitous character has led some scientists to consider the potential zoonotic risk of the human infection by Helicobacter heilmannii, felis or pylori. Finally, the Helicobacter infection of animals seems to be an interesting model not only in the study of the affections caused by these bacteria, but also in the elaboration of a future vaccine against the H. pylori infection in man.

During 1990-1992 a study of dose and image quality in mammography was carried out in the Madrid area. Values of air kerma and mean glandular dose per film estimated at 14 public and private centres (17 X-ray units) by means of the Leeds TOR(MAX) mammographic phantom and from a sample of patients were reported in a previous paper. This second paper describes image quality results obtained by the same Leeds TOR(MAX) phantom. Inferior image quality was found for units without a grid (most of them older systems) and/or using aluminium filtration. In units with a grid, inferior image quality was due to the low optical density of the images, the use of inadequate image receptors and the use of an aluminium filter. Image quality results were compared with the standards of the UK Breast Screening Programme and proposed European Guidelines. It is concluded that mammography image quality might be considered as acceptable when TOR(MAX) phantom films achieved at least 10 lp mm-1 and 1.2% for high contrast resolution and threshold contrast visibility (6 mm details) respectively.

The nonstructural protein NS1 of Japanese encephalitis virus is a major immunogen produced during flavivirus infection. However, the function of this protein has not been identified. To analyze its biochemical properties and evaluate its potential activity in the virus life cycle, the protein was produced in Spodoptera frugiperda insect cells (Sf9), using a recombinant baculovirus, and purified. As described previously by M. Flamand, V. Deubel, and M. Girard (1992, Virology 191, 826-836), a small fraction of the synthesized recombinant protein could mature into a dimer, whereas the major part was retained in intracellular aggregates. This insolubility was used to recover the protein in a purified form using a two-step procedure. Isolated inclusion bodies, in which NS1 constituted over 60% of the protein, were solubilized in 8 M urea. NS1 was further purified by reverse-phase HPLC and recovered at over 90% purity with an overall yield of over 60%. Conditions promoting reoxidation-renaturation of the purified protein were then investigated at a concentration of 100 micrograms/ml at pH 8. The presence of 8 M urea during reoxidation of NS1 with oxidized glutathione was essential prior to renaturation by dialysis to avoid reaggregation, the main side pathway of refolding in vitro. Three major species, all monomeric, were resolved by nonreducing SDS-PAGE. The form showing the lowest apparent molecular weight comigrated with native unreduced NS1 and was recognized by a monoclonal antibody directed against a conformational epitope strictly dependent on the native structure of the protein.(ABSTRACT TRUNCATED AT 250 WORDS)

A reverse phase liquid chromatographic (LC) method for the determination of chloramphenicol (CAP) residues in foies gras was tested. The method was based on acetonitrile-sodium chloride extraction, sample clean-up with hexane and purification on a Sep-Pak C18 cartridge. Acceptable chromatographic separation was obtained for thawed samples with two sample clean-up steps with hexane, a purification step with acetonitrile + water (87.5 + 12.5) (v/v) before the elution of CAP residues by a mixture of acetonitrile + water (70 + 30) (v/v) with a chromatographic separation on Spherisorb ODS-2 (5 microns) column using sodium acetate buffer (pH 4.3) + acetonitrile (78 + 22) (v/v) as mobile phase. The detection limit of the method was 2.5 micrograms/kg. The mean recovery from spiked samples at the 10 micrograms/kg level was 55.7 +/- 8.7%.

Dose values and image quality in mammography resulting from a study carried out in the area of Madrid during 1990-1991 are presented in a two-part sequence. In this paper are reported the values of air kerma and mean glandular dose per film estimated at 14 centres by means of the Leeds TOR(MAX) mammographic phantom and from patient samples. The results obtained from patient measurements allow us to deduce that the TOR(MAX) phantom assembly used (4.5 cm thick) is equivalent to an average 5 cm thick compressed breast from the population in the area of Madrid. Approximately 75% of the air kerma values resulting from phantom estimations are below 6.6 and 12.2 mGy for X-ray units with and without grid, respectively. The mean glandular doses per film for 75% of the units with and without grid are below 1.5 and 1.7 mGy, respectively. The results showed that the higher values of both air kerma and mean glandular dose obtained for the units without grid result from the use of slow speed recording systems. On the other hand, the quality control programme carried out shows important faults in the performance of the X-ray units which have an important impact on both dose and image quality. Finally, the third quartile values of the air kerma and mean glandular dose per film (10.4 and 1.7 mGy, respectively), deduced by considering all the units (with and without grid), are proposed to be the reference values of the mammographic examinations during the aforementioned period. In a second paper, the image quality is analysed by using the same Leeds TOR(MAX) phantom. Results for each test object included in the phantom are discussed as a function of the X-ray unit characteristics. Subsequently, the phantom images obtained with each X-ray system are scored and the resulting values are compared with the corresponding dose values, so that the dose-image quality relationship for each unit is obtained.

The penetration mechanism study of Venturia inaequalis is undertaken on leaves of scab-susceptible and scab-resistant apple cultivars. The penetration through the cuticle occurs whatever the host phenotype. The resistance will be expressed when the infectious hyphae is in contact with the epidermal cell wall. The epidermal cell of susceptible variety does not show any modification. The resistant variety reaction is very fast, since twenty hours after penetration many wall appositions are setting, the cytoplasm strongly degenerates and the parasite hyphae are already necrotic. The contact between the host and the parasite is always very complex in the case of resistant host. The rapidity and the important cytological modifications of the host parasite interaction connect this reaction to an hypersensitive reaction.

This study was undertaken to evaluate the effectiveness of 0.5% bupivacaine (360 mg/day) as a continuous infusion through an indwelling intercostal catheter inserted intraoperatively in the management of pain after thoracotomy. Eighty-six patients were randomized into three groups: group 1 = intercostal bupivacaine, group 2 = intercostal saline solution, and group 3 = fixed-schedule intramuscular buprenorphine. Supplementary buprenorphine was given as required. Pain and pulmonary function were assessed throughout the first 5 days after operation. Pain score was lower in group 1 than in group 2 for the first 8 hours after operation (p < 0.02). During the first 3 postoperative days, mean postoperative pain scores of 5 or more were recorded in 9% of group 1 patients versus 40% of group 2 patients (p < 0.05) and 13% of group 3 patients (not significant). Total doses of buprenorphine were lower in groups 1 and 2 than in group 3 (p < 0.001). No between-group differences in pulmonary function were observed. Respiratory complications occurred in no patients in groups 1 and 3 versus 5 in group 2 (p < 0.05). Continuous intercostal bupivacaine provided similar early pain control as compared with fixed-schedule narcotics but induced better analgesia with fewer complications than on-demand narcotics alone (group 2).

Pure epithelial cell cultures, obtained from primary culture of vas deferens tissue collected from 20- to 30-day-old mice, were amplified by subculturing the cells over 3T3 feeder layer in a serum-free defined medium. Adhesion and proliferation of epithelial cells did not require androgens, but a minimal concentration of 5.10(-7) M hydrocortisone. In that system, epithelial cells expressed cytokeratin but failed to produce the tissue specific mouse vas deferens protein (MVDP) in response to androgens. Various culture procedures and medium compositions were assayed for induction of MVDP expression. Culture onto microporous membrane inserts, which allow polarization of cells, is absolutely required for androgenic induction of MVDP. Androgen action did not require the presence of hydrocortisone, insulin, triiodothyronine, pituitary extracts, epidermal growth factor and acetylcholine. A minimal supplemented medium was then defined in which the expression of MVDP by epithelial cells in response to androgens was dose dependent. It has also been shown that this response at each concentration of dihydrotestosterone was heterogeneous at individual cell level. Highly reproducible results were obtained from epithelial cell cultures between 8th to 16th passages, showing that subcultured cells have maintained their ability to differentiate and express specialized functions.

The lizard epididymis is an androgen-dependent organ whose epithelial cells undergo marked changes in structure and secretory activity during the annual cycle. These changes are connected to fluctuations of testosterone levels. During the breeding season, the epididymis produces a major protein secretion, the L-proteins. In the present work we studied the fluctuations of RNA synthesis and accumulation during the annual cycle by means of histoautoradiographic methods. Total RNA synthesis was determined by uridine incorporation; accumulation of rRNAs and L-protein mRNAs were determined by in situ hybridization. Total RNA synthesis began during reorganization (Phase I), then increased gradually during differentiation and growth (Phase II). The synthesis peaked during maturation (Phase III), but stopped abruptly during hypersecretory activity (Phase IV). The rRNAs were very abundant from Phase II to Phase IV, which is related to the presence of many ribosomes as revealed by electron microscopy. The mRNAs of L-proteins were detected only during Phases III and IV in all epithelial cells. For every phase of the sexual cycle there exists a strong correspondence between the changes in transcriptional activity (rRNA and specific mRNA) of the epithelial cells and changes in the testosterone levels.

Klebsiella pneumoniae utilizes distinct pathways for the anaerobic and aerobic metabolism of glycerol. During anaerobic growth, glycerol is first converted to dihydroxyacetone by glycerol dehydrogenase; subsequent phosphorylation yields dihydroxyacetone phosphate. During aerobic growth, glycerol is initially phosphorylated to yield glycerol 3-phosphate; subsequent reduction then gives dihydroxyacetone phosphate. A coordinated response occurs when anaerobically growing cells are switched to aerobic conditions. Synthesis of glycerol dehydrogenase is repressed, glycerol dehydrogenase is inactivated, and the protein is degraded. Ethanol dehydrogenase and propanediol oxidoreductase are also inactivated when cells are exposed to oxygen (Johnson, E. A., Levine, R. L., and Lin, E. C. C. (1985) J. Bacteriol. 164, 479-483). Exposure of anaerobically growing cells to low concentrations of hydrogen peroxide also inactivated these three enzymes and led to rapid degradation of glycerol dehydrogenase. Glycerol dehydrogenase was purified and characterized after in vivo oxidative modification initiated by hydrogen peroxide. No differences in molecular weight, amino acid composition, or Km were detected between the native and oxidatively modified forms, although the modified enzyme had only 10% of the catalytic activity of the native form. The oxidatively modified enzyme was very susceptible to degradation by subtilisin while the native enzyme was resistant. Chloramphenicol prevented the inactivation and degradation of glycerol dehydrogenase caused by exposure to oxygen but did not block that caused by hydrogen peroxide. Thus, protein synthesis appears necessary for in vivo oxidative modification caused by exposure to oxygen but is not necessary when the process is initiated by exposure to hydrogen peroxide. The newly synthesized protein(s) presumably catalyzes the production of hydrogen peroxide which is required for the metal-catalyzed oxidative modification of susceptible enzymes.

A series of thirty consecutive epithelial ovarian cancer patients were reviewed after long-term follow-up (more than 5 y) since their second-look operation (SLO). All patients had advanced tumors (stages IIb-IV). Primary chemotherapy consisted of a cisplatin-associated regimen. For all patients adjuvant treatment had been planned after completion of the SLO. Mean follow-up after SLO was 68 months (47-103 months). Tumor status at SLO divided the patients in 2 subgroups: Group A = 13 patients (43%), with no evidence of histologically proved disease at time of operation (NED); Group B = 17 patients (57%), with macroscopic persistence of tumor. Survival was significantly better in the first group than in the second (77% at 5 yr vs less than 25%). Recurrence rate in the NED group was 7.7% (1 recurrence at 32 months). Eight of 17 patients with gross tumor at SLO underwent satisfactory resection. However, recurrence rate was high (75%) and survival rate was low (25% at 5 yrs). This result was not significantly better than that of patients with no optimal resection at SLO (9 patients, survival 22%). Second effort resection at SLO does not seem to be beneficial in these patients after partial failure of initial chemotherapy with cisplatin. The usefulness of systematic second look operations is discussed. Controlled randomized trials should be made to determine the exact role of SLO in ovarian cancer treatment.

Twenty-two heterosexuals and 21 homosexuals with chronic active hepatitis B and who had HBsAg, HBeAg and hepatitis B virus DNA in serum were randomized separately to receive adenine arabinoside monophosphate or placebo. In the 10 heterosexuals and nine homosexuals who received placebo, no change in hepatitis B virus DNA level and HBeAg was observed. Among the patients who received adenine arabinoside monophosphate, seven of the 12 heterosexuals and five of the 12 homosexuals lost hepatitis B virus DNA; five heterosexuals and three homosexuals also lost HBeAg; one homosexual lost HBsAg. There was no significant differences in response between heterosexual and homosexual patients. When results were pooled, there was a significant effect of adenine arabinoside monophosphate on hepatitis B virus replication. None of the 19 patients who received placebo but 50% of the 24 patients who received adenine arabinoside monophosphate were negative for serum hepatitis B virus DNA at 10 months after treatment (p less than 0.001) and none of the 19 patients who received placebo and 33% of the 24 patients who received adenine arabinoside monophosphate were negative for HBeAg in serum (p less than 0.005). Retrospective analysis showed that disappearance of hepatitis B virus DNA after administration of adenine arabinoside monophosphate was more common (i) in patients with a low pretreatment hepatitis B virus DNA level than in patients with a high pretreatment hepatitis B virus DNA level (8/11 vs. 4/13, p less than 0.05); (ii) in patients with a high pretreatment ALT level than in patients with a low pretreatment ALT level (10/14 vs. 2/10, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The purified regulatory (R) and catalytic (C) subunits of cAMP dependent protein kinase (cAK) from the primitive eukaryote Dictyostelium discoideum have been compared with the homologous proteins from bovine heart by SDS-PAGE followed by Western blotting using polyclonal antibodies. No cross-reaction could be demonstrated by this technique although the slime mold subunits share several functional properties with their mammalian counterparts and are able to form functional hybrid holoenzymes.

One to three months after hypophysectomy, porcine Leydig cells contain numerous dense bodies surrounded by a single membrane and crowded with dense rods geometrically arranged. In organotypic culture with HCG they undergo a striking evolution which leads first to intermediate bodies looking like peroxysomes and then to mitochondrial structures. This evolution is quantitatively reduced in a medium without HCG.

The natural history of infection with woodchuck hepatitis virus (WHV) has been studied in a colony of 38 Marmota monax. Besides serologic assessment for WHV markers, light-microscopic findings of 61 liver biopsies were correlated with the results of immunofluorescence analysis for nucleocapsid (WHcAg) and surface (WHsAg) antigens. Twenty-four chronic WHsAg carriers all featured signs of continuous viral replication. Two major immunomorphologic patterns were observed in their livers: 1) portal hepatitis in which WHcAg accumulated in the cytoplasm and WHsAg was associated with the hepatocyte membrane and 2) periportal hepatitis in which WHcAg shifted toward nuclear localization and WHsAg became mostly intracytoplasmic. Progression from portal to periportal hepatitis, observed in 7 woodchucks, appeared to be induced by a partial recovery of specific immune reactivity to WHV, insufficient, however, to interrupt WHV replication. Deposits of WHsAg and immunoglobulins were present in the kidney and spleen of animals with severe hepatitis.

Boar Leydig cells undergo a strong atrophy from 1 to 3 months after hypophysectomy but can be reactivated by the gonadotropin HCG in organ culture conditions. This reactivation which appeared at histological and ultrastructural level was evidenced by the capacity of testicular tissue to synthesize testosterone as judged by radioimmunoassay. Both synthesis in the tissue and release into the medium increased according the incubation time with HCG; the adjonction of 17 alpha-OH-pregneolone to culture medium led to increase the intra and extra-tissular concentration of testosterone.

Hypophysectomy of the boar resulted in a rapid drop in plasma testosterone level. hCG injections (400 IU/day) considerably elevated testosteronemia (up to 16.41 ng/ml). This effect was obtained either in the days following the operation or several months after (up to 134 days). In the latter case, the effect was temporary because the testosterone level dropped again after 15 days of injections. The sexual target organs (epididymis, seminal vesicle, prostate and Cowper glands) underwent structural change which, in the epithelium, corresponded to fluctuations in testosterone level. These effects were less marked in the cauda epididymis than in other target tissues. In various target organs, the conjunctivomuscular stroma developed after the operation; it did not regress at all, or incompletely, when the epithelia were stimulated indirectly by hCG, and began to hypertrophy when the hCG was no longer effective. Variations in stromal reaction were organ-dependent. When the hCG was administered for more than 14 days, it seemed to have a desensitizing effect; these mechanisms have been discussed.

The authors studied experimentally ovario-uterine implantation in rats, an operation first performed many years ago yielding very rare and debatable results. This procedure is ineffective in the treatment of sterility due to endometrial proliferation over the ovary, which closes off rapidly the endometrial cavity and separates it from the implanted ovary. Much uncertainty surrounds the majority of previously reported successes, the few resultant pregnancies from ovario-uterine implantation considered due to hazard and completely unreliable. This operation has no place in the treatment of sterility.

Minced whole testes from immature pigs were treated with collagenase (0.4 mg/ml) then with trypsin (2.5 mg/ml). The resulting suspension of cells was divided into sterile bottles containing medium 199 supplemented with 5 p. 100 calf serum. Bottles were maintained at 32 degrees C. After about 24 hours medium was changed 3 times to eliminate free cells. Within 3 days preparations consisting of 81.5% Sertoli cells, 0.5% Leydig cells and 18% peritubular cells were obtained.

A simple and rapid high-performance liquid chromatography (HPLC) method for the determination of chloramphenicol (CAP) residues in trout muscle tissue is described. After an acetonitrile-sodium chloride extraction followed by washing with hexane and purification through a Sep-Pak C18 cartridge, analysis is performed by reversed-phase HPLC on Spherisorb ODS-II (5 microgram) using water-methanol (1:1) as the mobile phase. The detection limit of the method is 5 micrograms/kg. The mean recovery from spiked muscle samples at the 10-micrograms/kg level is 56 +/- 7.4%. CAP residues are confirmed by gas chromatography-mass spectrometry at concentrations as low as 1 micrograms/kg. Residues were detected in trout muscle after oral administration during 15 days. On the tenth day after treatment, an average of CAP of less than 5 micrograms/kg was measured. No residues were detected after the twentieth day.

The lizard epididymis provides a model for studying the control, by testosterone, of a secretory activity related to the physiology of spermatozoa. To evaluate seasonal changes and to establish chronological correlations between the structure of the epididymis and its testosterone content, lizards (Lacerta vivipara) were killed between March (emergence) and October (retreat). The epididymal tissue was examined histologically and assayed for testosterone content. Ten stages of development were defined, mainly on the basis of the epithelial structure and the morphological features of secretory activity. Degeneration of the epithelium after the breeding period and its subsequent renewal also were considered. Increased epithelial height and secretory activity coincided with a progressive rise of the testosterone level, and a severe atrophy followed a sudden reduction of blood testosterone. Reorganization of the epithelium takes place when testosterone is at its lowest level, and the hormonal dependency of this stage is questionable. This study confirms in vivo, during a sexual cycle, experimental evidence previously obtained concerning testosterone's control of the secretory activity of the lizard epididymis.

A lectin activity inhibitable by thiodigalactose, N-acetyllactosamine, lactulose, lactose and by an antibody raised against CLL I (chicken-lactose lectin I) has been investigated in the chick embryo developing kidney. At post-induction stages this activity was found in both mesonephros and metanephros. In immunofluorescence and immunoelectron microscopy, the extracellular distribution of CLL I was similar in the mesonephros and the metanephros. The lectin was never found intracellularly; cultured kidney cells did not express any endogenous lectin but were rich in lectin-receptor sites, which led to the hyphothesis that CLL I is not produced in situ but could be adsorbed on renal cells. Potential physiological roles for embryonic lectins are discussed.

Experimental studies on survival of Vibrio cholerae in untreated sea-water reveal that they remain alive at least one week. A somewhat longer survival (up to 3 weeks) could be observed if these bacteria were kept in sea-water sterilized by filtration. But if sea-water is autoclaved, cholera vibrios may keep their vitality for periods at least 6 months. Our observations lead to the conclusion that untreated sea-water may contains some filtrable thermolabile factor killing cholera vibrios. Yet these facts should not create false feelings of security. It is known, from recent epidemiological data that sea-medium as a whole may be the origin of cholera outbreak.