Prospecting potential links between PRRSV infection susceptibility of alveolar macrophages and other respiratory infectious agents present in conventionally reared pigs

Porcine Reproductive and Respiratory Syndrome virus (PRRSV) is one of the main component of the porcine respiratory disease complex (PRDC), which strongly impact the pig production. Although PRRSV is often considered as a primary infection that eases subsequent respiratory coinfections, the possibility that other PRDC components may facilitate PRRSV infection has been largely overlooked. The main cellular targets of PRRSV are respiratory macrophages among them alveolar macrophages (AM) and pulmonary intravascular macrophages (PIM). AM, contrarily to PIM, are directly exposed to the external respiratory environment, among them co-infectious agents. In order to explore the possibility of a co-infections impact on the capacity of respiratory macrophages to replicate PRRSV, we proceed to in vitro infection of AM and PIM sampled from animals presenting different sanitary status, and tested the presence in the respiratory tract of these animals of the most common porcine respiratory pathogens (PCV2, Actinobacillus pleuropneumoniae, Mycoplasma hyopneumoniae, Mycoplasma hyorhinis, Mycoplasma floculare, Pasteurella multocida, Bordetella bronchiseptica, Streptoccocus suis). In this exploratory study with a limited number of animals, no statistic differences were observed between AM and PIM susceptibility to in vitro PRRSV infection, nor between AM coming from animals presenting very contrasting respiratory coinfection loads.

NIST Interlaboratory Study on Glycosylation Analysis of Monoclonal Antibodies: Comparison of Results from Diverse Analytical Methods

Glycosylation is a topic of intense current interest in the development of biopharmaceuticals because it is related to drug safety and efficacy. This work describes results of an interlaboratory study on the glycosylation of the Primary Sample (PS) of NISTmAb, a monoclonal antibody reference material. Seventy-six laboratories from industry, university, research, government, and hospital sectors in Europe, North America, Asia, and Australia submitted a total of 103 reports on glycan distributions. The principal objective of this study was to report and compare results for the full range of analytical methods presently used in the glycosylation analysis of mAbs. Therefore, participation was unrestricted, with laboratories choosing their own measurement techniques. Protein glycosylation was determined in various ways, including at the level of intact mAb, protein fragments, glycopeptides, or released glycans, using a wide variety of methods for derivatization, separation, identification, and quantification. Consequently, the diversity of results was enormous, with the number of glycan compositions identified by each laboratory ranging from 4 to 48. In total, one hundred sixteen glycan compositions were reported, of which 57 compositions could be assigned consensus abundance values. These consensus medians provide community-derived values for NISTmAb PS. Agreement with the consensus medians did not depend on the specific method or laboratory type. The study provides a view of the current state-of-the-art for biologic glycosylation measurement and suggests a clear need for harmonization of glycosylation analysis methods.

Transcriptional changes in Crassostrea gigas oyster spat following a parental exposure to the herbicide diuron

The Pacific oyster Crassostrea gigas is the main oyster species produced in the world, and a key coastal economic resource in France. High mortalities affect Pacific oysters since 2008 in France and Europe. Their origins have been attributed to a combination of biotic and abiotic factors, underlining the importance of environment quality. The impact of water pollution has been pointed out and one of the pollutants, the genotoxic herbicide diuron, occurs at high concentrations all along the French coasts. Previous work has revealed that a parental exposure to diuron had a strong impact on hatching rates and offspring development even if spats were not exposed to diuron themselves. In this study, we explored for the first time the transcriptional changes occurring in oyster spats (non exposed) originating from genitors exposed to an environmentally relevant concentration of diuron during gametogenesis using the RNAseq methodology. We identified a transcriptomic remodeling revealing an effect of the herbicide. Different molecular pathways involved in energy production, translation and cell proliferation are particularly disturbed. This analysis revealed modulated candidate genes putatively involved in response to oxidative stress and mitochondrial damage in offspring of genitors exposed to diuron. Complementary measures of the activity of enzymes involved in these latter processes corroborate the results obtained at the transcriptomic level. In addition, our results suggested an increase in energy production and mitotic activity in 5-month-spats from diuron-exposed genitors. These results could correspond to a "catch-up growth" phenomenon allowing the spats from diuron-exposed genitors, which displayed a growth delay at 3 months, to gain a normal size when they reach the age of 6 months. These results indicate that exposure to a concentration of diuron that is frequently encountered in the field during the oyster's gametogenesis stage can impact the next generation and may result in fitness disturbance.

Effects of an environmentally relevant concentration of diuron on oyster genitors during gametogenesis: responses of early molecular and cellular markers and physiological impacts

Genitors of the Pacific oyster Crassostrea gigas were submitted during gametogenesis to a short pulse exposure to the herbicide diuron at a realistic environmental concentration. Histological analysis showed no effect of diuron on gametogenesis course, sex ratio and reproductive effort. A non-significant increase in testosterone and progesterone levels was observed in genitors exposed to the herbicide. At cell level, diuron exposure was shown to modulate the phagocytic activity of circulating hemocytes. The results of a transcriptional analysis showed that diuron affected the expression of genes belonging to functions known to play a major role during oyster gametogenesis such as gene transcription regulation, DNA replication and repair, DNA methylation and cytokinesis. Taking into account the results we previously obtained on the same genitors, this study showed a negative effect of diuron on oyster reproduction by inducing both structural and functional modifications of the DNA.

Study of genetic damage in the Japanese oyster induced by an environmentally-relevant exposure to diuron: evidence of vertical transmission of DNA damage

Pesticides represent a major proportion of the chemical pollutants detected in French coastal waters and hence a significant environmental risk with regards to marine organisms. Commercially-raised bivalves are particularly exposed to pollutants, among them pesticides, as shellfish farming zones are subject to considerable pressure from agricultural activities on the mainland. The aims of this study were to determine (1) the genotoxic effects of diuron exposure on oyster genitors and (2) the possible transmission of damaged DNA to offspring and its repercussions on oyster fitness. To investigate these points, oysters were exposed to concentrations of diuron close to those detected in the Marennes-Oleron Basin (two 7-day exposure pulses at 0.4 and 0.6 μg L(-1)) during the gametogenesis period. Genomic abnormalities were characterized using two complementary approaches. The Comet assay was applied for the measurement of early and reversible primary DNA damage, whereas flow cytometry was used to assess the clastogenic and aneugenic effect of diuron exposure. Polar Organic Chemical Integrative Samplers (POCIS) were used in exposed and assay tanks to confirm the waterborne concentration of diuron reached during the experiment. The results obtained by the Comet assay clearly showed a higher level of DNA strand breaks in both the hemocytes and spermatozoa of diuron-exposed genitors. The transmission of damaged genetic material to gamete cells could be responsible for the genetic damage measured in offspring. Indeed, flow cytometry analyses showed the presence of DNA breakage and a significant decrease in DNA content in spat from diuron-exposed genitors. The transmission of DNA damage to the offspring could be involved in the negative effects observed on offspring development (decrease in hatching rate, higher level of larval abnormalities, delay in metamorphosis) and growth. In this study, the vertical transmission of DNA damage was so highlighted by subjecting oyster genitors to short exposures to diuron at medium environmental concentrations. The analysis of POCIS showed that oysters were exposed to integrated concentrations as low as 0.2 and 0.3 μg L(-1), emphasizing the relevance of the results obtained and the risk associated to chemical contamination for oyster recruitment and fitness.

Relationship between PAH biotransformation as measured by biliary metabolites and EROD activity, and genotoxicity in juveniles of sole (Solea solea)

Polycylic aromatic hydrocarbons (PAHs) are ubiquitous contaminants in the marine environment. Their toxicity is mainly linked to the ability of marine species to biotransform them into reactive metabolites. PAHs are thus often detected at trace levels in animal tissues. For biomonitoring purposes, this findings have two main consequences, (i) the determination of the PAH tissue concentration is not suitable for the evaluation of individual exposure to PAHs (ii) it can explain sometimes the lack of correlations obtained with relevant markers of toxicity such as genotoxicity biomarkers. The aim of the present study was to better investigate the link between PAH exposure and genotoxicity in marine flatfish. During a laboratory experiment, juvenile soles were exposed for four weeks to a mixture of three PAHs, namely benzo[a]pyrene, fluoranthene and pyrene, followed by one week of depuration. Fish were exposed via the trophic route to a daily PAH concentration of 120 μg/g food. Fish were sampled at different time points. The bioavailability and the biotransformation of PAHs were assessed by the measurement of biliary metabolites using a sensitive UPLC MS/MS method. The 7-ethoxyresorufine-O-deethylase was also measured in liver subcellular fractions as a biomarker of phase I biotransformation activities. Genotoxicity was assessed in parallel by the measurement of DNA strand breaks in fish erythrocytes by the alkaline comet assay. During this study, the high amount of PAH metabolites produced in sole demonstrated the bioavailability of PAHs and their biotransformation by fish enzymes. A positive correlation was observed between the level of hydroxylated PAH metabolites and genotoxicity as measured by the alkaline comet assay.

Seasonal variations of a battery of biomarkers and physiological indices for the mussel Mytilus galloprovincialis transplanted into the northwest Mediterranean Sea

Seasonal variations of six mussel (Mytilus galloprovincialis) biomarkers at two sites in the Mediterranean Sea were compared with physiological indices (condition, growth and gonad maturation), environmental parameters (temperature, salinity and turbidity), and chemical contamination levels. The basal levels of acetylcholinesterase (AChE), DNA adducts, benzo[a]pyrene hydroxylase (BPH), heat-shock proteins (HSP70), metallothioneins (MT) and P-glycoprotein (P-gp)-mediated multixenobiotic resistance (MXR) were estimated as early warning signals in caged mussels sampled at Carteau (native site) and La Fourcade (transplantation site) over a 2-year period. The Carteau and La Fourcade mussels have specific chemical contamination profiles but a similar range of values. For example, both are highly contaminated by heavy metals (201 and 258.4 mg kg(-1) dw, respectively) and considered as moderately impacted for polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). However, contamination levels at Carteau are twice as high for PAHs (101.5 mg g(-1) dw) and PCBs (90.2 mg g(-1) dw) than La Fourcade. The seasonal contamination trend at Carteau showed six-fold higher levels of pyrolytic pollutants in winter. Although few tissue lesions were detected in individuals studied at either site, greater parasitic infestation was observed at Carteau. The results of findings from the two Mediterranean pilot studies support the adaptability of transplanted mussels to be used as biomarkers and to establish physiological endpoints for chemical contaminant exposure.

[Results of active surveillance of acute flaccid paralysis in the Central African Republic and Chad from 1995 to 2000]

The threefold purpose of this report is to describe the epidemiology of acute flaccid paralysis (AFP), to determine the impact of the National Immunization Days (NID), and evaluate the quality of active surveillance in the Central African Republic (CAR) and Chad. The data in this study was obtained from the Enterovirus Division of the Pastear Institute in Bangui (National WHO Inter-country Reference Laboratory for the CAR and Chad and Regional Poliovirus Reference Laboratory in Africa). An increase in the number of AFP cases was observed in the CAR between 1995 and 2000 and in Chad between 1997 and 2000, mainly as a result of enhancement of the surveillance system. The goals set by the WHO in terms of the proportion of AFP cases with 2 specimens collected within 14 days of onset of paralysis and the number of cases with 60-day follow-up have not been reached in either country. The presence of 2 strains of wild poliovirus (types 1 and 3) and several genotypes (West African 13 and West African 7 for type 1 and Central African and Nigeria-P3 for type 3) not only show that Central Africa is still a significant reservoir for poliovirus transmission but also raise serious doubts about the quality of the NID organized over the last 3 years. The priority of the next NID round must be to reach unimmunized children who have been missed by routine immunization coverage.

Macrophagic myofasciitis associated with inclusion body myositis: a report of three cases

We describe three patients with macrophagic myofasciitis and inclusion body myositis. All patients fulfilled diagnostic criteria for inclusion body myositis and myopathologic criteria for macrophagic myofasciitis. In the three cases macrophagic myofasciitis complicated the evolution of a known and painless inclusion body myositis and was diagnosed in a repeated deltoid biopsy because of the appearance of myalgia during the course of inclusion body myositis in all cases. The unexpected appearance of myalgia during the course of painless inclusion body myositis must arouse the suspicion of an association of another inflammatory muscle disease, macrophagic myofasciitis.

[Immunoblot applied to the diagnosis of congenital toxoplasmosis]

Western blot was evaluated for the neonatal diagnosis of congenital toxoplasmosis based on a comparison of antibody profiles between serum samples obtained from the mother at delivery and from the neonate. Passively transferred antibodies can be distinguished from antibodies produced by the neonate, thus allowing early postdelivery diagnosis of congenital toxoplasmosis before the results of other tests are available. This method was developed at the Parasitology-Mycology laboratory of the Pitié-Salpêtrière Teaching Hospital, Paris, France, then evaluated in a retrospective study of 52 mother-infant pairs. The diagnosis of congenital toxoplasmosis was ruled out in 34 cases, confirmed in ten cases, and doubtful in 8 cases. Sensitivity was higher than with conventional serological tests. Antibody profile differences were found between mothers and affected infants; these differences usually involved IgGs (8 of 9 cases). Importantly, in two cases Western blot would have provided the diagnosis of congenital toxoplasmosis two months before the secondary elevation in IgM titers in one case and three weeks before the result of mouse placenta inoculation in another case. In conclusion, Western blot deserves to be used to complement established methods (serology and direct demonstration of the parasite by gene amplification, cell cultures, and mouse inoculations) as a means of rapidly (within 24 hours of receipt of the specimen) providing clinicians with information relevant to treatment decisions.

Enterovirus genome detection in wastewater: multi centric evaluation of a commercial kit

A multi-centric study was carried out in three laboratories, to evaluate the efficiency of a standardized kit for the detection of enterovirus genome in wastewater. Twenty one samples of 20 liters of wastewater were analyzed before and after concentration through glass wool. Each sample was analyzed with the Amplicor kit as well as with techniques developed independently in each laboratory. The results show that the Amplicor kit is well suited to the detection of enterovirus genome in treated wastewater. The results may be compared to those obtained with semi-nested RT-PCR techniques used in each laboratory. However, the Amplicor kit technique is more simple and has the advantage of providing a standardized technique useful for comparative studies. During this work it was observed that the sensitivity of the detection of infectious viruses and virus genome was improved when concentrated samples were used for analysis.

Structural modifications of the N-terminal tetrapeptide segment of [D-Ala2]deltorphin I: effects on opioid receptor affinities and activities in vitro and on antinociceptive potency

A series of deltorphin I analogs containing D- or L-N-methylalanine (MeAla), D- or L-proline (Pro), alpha-aminoisobutyric acid (Aib), sarcosine (Sar) or D-tert-leucine (Tle) in place of D-Ala2, or phenylalanine in place of Tyr1, was synthesized. The opioid activity profiles of these peptides were determined in mu and delta opioid receptor-representative binding assays and bioassays in vitro as well as in the rat tail flick test in vivo. In comparison with the deltorphin I parent, both the L- and the D-MeAla2-analog were slightly more potent delta agonists in the mouse vas deferens (MDV) assay, and the D-MeAla2-analog showed two-fold higher antinociceptive potency in the analgesic test. In view of the fact that deltorphin analogs with an unsubstituted L-amino acid residue in the 2-position generally lack opioid activity, the observed high delta opioid potency of [L-MeAla2]deltorphin I is postulated to be due to the demonstrated presence of a conformer with a cis Tyr1-MeAla2 peptide bond, since the cis conformer allows for a spatial arrangement of the pharmacophoric moieties in the N-terminal tripeptide segment similar to that in active deltorphin analogs containing a D-amino acid residue in the 2-position. Substitution of Aib in the 2-position led to a compound, H-Tyr-Aib-Phe-Asp-Val-Val-Gly-NH2, which displayed lower delta receptor affinity than the parent peptide but higher delta selectivity and, surprisingly, three times higher antinociceptive potency. The D- and L-Pro2-, Sar2- and D-Tle2-analogs showed much reduced delta receptor affinities and were inactive in the tail flick test. Replacement of Tyr1 in deltorphin I with Phe produced a 32-fold decrease in delta receptor affinity but only a 7-fold drop in antinociceptive potency.

Value of nocturnal penile tumescence and rigidity (NPTR) recording in impotent patients with multiple sclerosis

The etiology of impotence in patients with multiple sclerosis (MS) is difficult to assess due to the possibility of normal nocturnal penile tumescence and rigidity (NPTR) recording despite neurologic involvement. Sixteen patients with MS and impotence were studied with Rigiscan, cavernous artery doppler, neurophysiological tests and intracavernous injection of PGE1. When more restrictive criteria of normality than usual are used for Rigiscan (rigidity > or = 80% and/or duration > 30 minutes), an inverse relationship between NPTR recording and sexuality score or PGE1 dose is reported. No significant difference is noted for neurophysiological tests. With such criteria, Rigiscan alone or combined with intracavernous PGE1 is a valuable means to differentiate neurogenic from psychogenic impotence in MS patients. Neurophysiological tests are of limited clinical value.

[Evolution of the Mycobacteria Laboratory of the Pasteur Institute of Madagascar from 1991 to 1994]

In 1991, the Laboratory of Mycobacteria was a small laboratory, part of the Clinical Biology Centre (CBC) of the Institut Pasteur de Madagascar: 656 pathological samples have been analysed for the account of the CBC and the National Control Programme activities. Within 4 years, the number of samples tested increased by more than threefold and the technical ability has evolved in an important way, specially for the identification and the antibiotic sensitivity testing. The scientific equipment have been modernized and the rooms surface increased by fourfold. In 1995, this laboratory was officially designated as the National Reference Laboratory for the culture, the identification and antibiogramme for the account of the National Control programme and for the private clinicians. It also participates to the tuberculosis research programmes of Institut Pasteur de Madagascar. It is associated to the Laboratory of Mycobacteria in the Institut d'Hygiène Sociale of Antananarivo which is the National Reference Laboratory for the bacilloscopy, the teaching and the supervision of the peripheral laboratories.

Detection of hepatitis A virus, rotavirus, and enterovirus in naturally contaminated shellfish and sediment by reverse transcription-seminested PCR

A reverse transcription-PCR method was developed to detect enterovirus (EV), hepatitis A virus (HAV), and rotavirus (RV) RNAs in shellfish and sediment. The method was first tested under experimental conditions by using virus-spiked shellfish to evaluate assay sensitivity. The use of CC41 cellulose was found to be efficient for removing inhibitors of RV detection. For sediment samples, a Sephadex column was used to allow the detection of EV and HAV RNAs. The specificity of amplified products was controlled by hybridization with digoxigenin-labeled oligoprobes. The method was then applied to naturally contaminated shellfish and sediments. EV, HAV, and RV RNAs were detected in 22, 14, and 20% of the shellfish samples, respectively. No relationship between viral contamination and bacterial contamination was found. When viral RNAs (HAV or EV) were detected in sediments, they were also detected in shellfish.

Occurrence of a multiple sclerosis-like illness in women who have a Leber's hereditary optic neuropathy mitochondrial DNA mutation

Eight women are described who presented with bilateral, usually sequential, optic neuropathy, six of whom later developed a neurological syndrome indistinguishable from multiple sclerosis (MS). Magnetic resonance imaging, performed in five of the patients with an MS-like illness and in the two others with optic neuropathy alone, showed widespread white matter lesions as seen in MS. All of these women had matrilineal relatives with Leber's hereditary optic neuropathy, although this was not always apparent at presentation, and the most common mitochondrial DNA mutation associated with this disorder was detected in each of the women and their affected relatives. On the basis of observations made in these patients, the clinical features of Leber's hereditary optic neuropathy in males, and evidence for mitochondrially encoded peptides involved in the immune response in rodents, we propose that optic nerve damage in this disease could be immunologically mediated and that mitochondrial genes may contribute to susceptibility to MS.

Occurrence of faecal bacteria, Salmonella and antigens associated with hepatitis A virus in shellfish

An investigation was carried out over a one year period to examine jointly the occurrence of faecal bacteria, salmonella and the presence of antigens associated with the hepatitis A virus (HAV) in oysters (Crassostrea gigas), mussels (Mytilus edulis, Mytilus galloprovincialis) and cockles (Cerastoderma edule), taken from 8 shellfish farming areas or natural beds along the French coast. For the faecal coliforms (FC) and faecal streptococci (FS), statistical analysis of the 176 samples examined shows a statistically significant difference between sampling stations (F = 44.39 and F = 26.69 respectively, p less than 0.001): 4 of the 8 stations are more highly contaminated. Salmonella and antigens associated with HAV were detected in 5% and 1.7% respectively of the samples analysed. Frequency of isolation of salmonella is higher for the group of sampling stations where the mean levels of contamination by FC and FS are highest. The presence of HAV associated antigens was detected for the group of stations showing the lowest mean contamination levels. Taking all sample stations together, the percentage of isolation of salmonella differs significantly (chi 2 = 7.28, p less than 0.01) for the two classes of FC established on the basis of the threshold value (300 FC). There is no difference between the two classes of FS. For the HAV-associated antigens, detection percentages are similar for the two classes of results for FC and FS. Within each sampling station, considered independently, no particular correlation was found between the various viral and bacterial markers investigated.

Neurobehavioral profile of neuropeptide Y

In order to better delineate the profile of central actions of neuropeptide Y (NPY), the effects of intracerebroventricular administration of several doses (2.5-20 micrograms) of the peptide on spontaneous activity, muscular tone, body temperature, food intake, nociception and cataleptic manifestations were examined in rats. Results indicate that, starting at 5 micrograms. NPY significantly decreased motor activity of animals in a dose-related fashion. NPY also significantly lowered body temperature of animals. The hypothermic effect was obtained following injections of 10.0 and 20.0 micrograms of the peptide. Administration of the same two doses of NPY resulted in significant increases in food intake, muscular tone and induced a significant catalepsy in animals. On the other hand, nociceptive response times of animals in the hot plate test were not affected by any of the NPY doses tested. Together, these results indicate that the profile of NPY's neurobehavioral actions is more complex than previously reported and suggest that the peptide might be implicated functionally in a variety of neurophysiological processes.

In vivo structure activity study supports the existence of heterogeneous neuropeptide Y receptors

The purpose of the present study was to examine relationships between structure and activity of the peptide for stimulating food intake and decreasing body temperature in rats. Various NPY fragments and structural analogs were administered intracerebroventricularly in several doses (2.5-160 micrograms) and their effects on feeding and body temperature evaluated and compared. Globally, results indicate that the C-terminal portion of the peptide is responsible for both central effects of NPY. However, the distributions of potencies of the various fragments and analogs for increasing food intake and decreasing body temperature were clearly different. The most salient difference was that deletion of the N-terminal residue Tyr1 of NPY resulted in a five-fold loss in the potency for decreasing rectal temperature, whereas NPY2-36 was relatively more potent than the native peptide to increase food intake in animals. These results suggest that the purported receptors mediating the effect of NPY on food intake are different than those responsible for the influence of the peptide on body temperature. The results of the present in vivo work are discussed in relation to those obtained in previous in vitro studies.

Neurobehavioral evidence for kappa agonist activity of the morphinan derivative 14-beta-methyl 8-oxacyclorphan [BC (3016)]

The purpose of the present study was to determine if the in vivo neurobehavioral effects of the morphinan 14-beta-methyl 8-oxacyclorphan, [BC (3016)], would reflect the kappa agonist activity found in our previous in vitro studies. The effects of intracisternal administration of various doses (10-80 micrograms) of BC (3016) on body temperature, muscle rigidity, nociception of thermal, chemical and mechanical stimuli as well as its ability to induce catalepsy were examined. The effects of intrathecal administration of the same doses of the compound on reactivity of animals to a thermal stimulus were also assessed. Finally, the ability of BC (3016) to antagonize well known neurobehavioral effects of morphine was investigated. Results indicate that the analgesic properties of BC (3016) resemble those of typical kappa agonists: Intracisternal administration of the drug failed to affect nociception to an aversive thermal stimulus but markedly reduced the reactivity of animals subjected to noxious chemical or mechanical stimuli. On the other hand, intrathecal administration of BC (3016) significantly attenuated nociception of animals to a thermal stimulus. The in vivo neurobehavioral effects of BC (3016) appear to be kappa selective since the drug did not decrease body temperature, increase muscular tone or induce catalepsy, three effects generally attributed to mu agonists. Furthermore, BC (3016) antagonized the immobility, trunk rigidity, catalepsy and analgesia induced by morphine. In summary, the present results reveal that BC (3016) displays a profile of neurobehavioral effects similar to that of well known kappa agonists.

Effects of captopril and minoxidil on left ventricular hypertrophy in resistant hypertensive patients: a 6 month double-blind comparison

In a double-blind 6 month trial, the cardiac effects of captopril and minoxidil, administered as third step treatments, were compared in 34 men with essential hypertension and diastolic blood pressure greater than 95 mm Hg who were taking 200 mg/day of metoprolol and 80 mg/day of furosemide. Average daily doses of captopril and minoxidil were 269 mg (range 150 to 300) and 20 mg (range 7.5 to 30), respectively. At the end of the 6 months' treatment, blood pressure had dropped significantly in both groups, but echocardiographic criteria of hypertrophy improved only in the captopril group (intragroup comparison): blood pressure, thickness of the intraventricular septum and posterior wall, and the left ventricular mass index, respectively, decreased from 163/102 to 135/89 mm Hg (p less than 0.001), 17.4 to 15.9 mm (p less than 0.05), 14.5 to 13.4 mm (p less than 0.05) and 236 to 198 g/m2 (p less than 0.001). In the minoxidil group, blood pressure dropped from 160/99 to 137/87 mm Hg (p less than 0.001), but echocardiographic criteria were not significantly modified. Fractional shortening remained normal in both groups. These results show that in patients with severe left ventricular hypertrophy, captopril-based triple therapy reduces left ventricular mass without altering systolic performance, whereas minoxidil-based therapy does not.

The aging athlete

In summary, the purpose of this material is to demonstrate that the aging athlete does differ from the younger competitor in many facets. There are physiological, structural, and psychosocial differences which distinguish them as a unique entity in the athletic world. Despite the unavoidable alterations that the passage of time imposes on our bodies, these competitors are still capable of incredible performances of strength, skill, and endurance. In reference to injury, these athletes are at risk from both their current program and their past indiscretions. The literature strongly suggests that the greatest threat to the health of the aging athlete is not the aging process itself but rather inactivity. Astrand concurs with this and states that "there is less risk in activity than in continuous inactivity--it is more advisable to pass a careful physical examination if one intends to be sedentary in order to establish whether one's state of health is good enough to stand the inactivity." It appears that the body systems were designed to reinforce activity and when there is disuse, a large number of atrophic changes take place. It has been estimated that regular exercise may be able to retard the physiologic decline associated with old age as much as 50%. Taken in this light, exercise is truly a fountain of youth from which we can all rejuvenate ourselves. Science has proven that life does not begin at 40, but it has also demonstrated that it does not have to end there. As one author so aptly states, "Not too many years ago the words grandma and grandpa conjured images of rocking chairs and inactivity."(ABSTRACT TRUNCATED AT 250 WORDS)

Autoradiographic localization of [3H]-thymidine incorporation in developing human esophagus

Cell proliferation in the developing human esophagus was investigated by autoradiography using organ culture. The sites of [3H]-thymidine uptake were localized in the epithelium, the mesenchyme, and the muscularis externa of fetal esophageal explants from 10 to 16 weeks of gestation. Proliferating cells were abundant throughout the stratified epithelium at 10 weeks of gestation. Many labeled nuclei in the mesenchyme and the muscular layer were observed. With the development of the stratified columnar ciliated epithelium, a confinement of the proliferating zone in the basal cell layers occurred, and ciliated cells never appeared labeled. The quantitation of proliferating cells showed a labeling index at its highest value between 10 and 12 weeks; this drastically decreased between 12 and 14 weeks' gestation. A similar pattern was noted for the mesenchyme, while the labeling index in the muscularis externa peaked during the 11-14 weeks period. In all fetuses, the highest labeling index was always recorded in the epithelium. The biochemical quantitation of the [3H]-thymidine uptake into the total esophageal DNA clearly supported the continuous decrease of the cell proliferation determined by autoradiography between 10 and 16 weeks of gestation. The present investigation provides for the first time basic quantitative data regarding cell proliferation during a particular developmental phase of the human esophagus.

Development of peroxisomes in amphibians. III. Study on liver, kidney, and intestine during thyroxine-induced metamorphosis

This investigation was undertaken to study the ontogeny of hepatic, renal, and intestinal peroxisomes and/or microperoxisomes during thyroxine-induced anuran metamorphosis. Catalase activity was localized cytochemically after incubation in DAB medium, and studied biochemically by a spectrophotometric method. Our morphological and biochemical investigations suggest the formation of a new population of peroxisomes during the hormonal treatment. This is obvious especially for microperoxisomes of the intestinal epithelium since the larval tissue is completely replaced by a new layer during thyroxine-induced metamorphosis. For the peroxisomes of hepatocytes and kidney proximal tubule cells, our assumption is based on the following observations: 1) The number of peroxisomes increases in liver and kidney during thyroxine treatment; 2) this proliferation is accompanied by an enlargement of renal peroxisomes; and 3) 16 days after the beginning of the hormonal treatment, 5.4- and 2.4-fold increases are found for the specific activities of hepatic and renal catalase, respectively. A temporal coordination exists between the structure and the metabolism of peroxisomes and mitochondria during thyroxine-induced metamorphosis.

Conformational dynamic investigation of 1,5-benzodioxepin and its dimethyl derivative by 1H and 13C nmr

The conformational and dynamic properties of 1,5-dioxa-6,7-benzocycloheptene (2; 1,5-benzodioxepin) and its dimethyl derivative (7) have been investigated by dynamic 1H and 13C nmr methods. Analysis of the spectra at low temperatures (below coalescence) indicates that the most stable seven-membered ring conformations detected for solutions in CHF2Cl are a mixture of the chair (C, 80%) and the twist-boat (TB, 20%) for 2 and a mixture of TB (64%) and C (36%) for 7. Free energy barriers were determined for the chair inversion of 2 (6.5 kcal/mol) and 7 (7.5 kcal/mol) as well as for the twist-boat pseudorotation of 7 (6.8 kcal/mol). The conformational properties of these seven-membered heterocycles are discussed and compared to those known for 2,4-benzodioxepins.

Organ culture of adult mouse intestine. III. Behavior of the proteins, DNA content and brush border membrane enzymatic activities

The proteins, the DNA content and the brush border membrane enzyme activities of adult mouse intestinal explants have been measured during a 24-hr organ culture. These activities were not modified in comparison with the controls at the beginning of the culture. The activity of the enzymes secreted in the medium during the 24-hr culture was equal to the activity present in the explants at the start of the culture. These results show that several metabolic functions of the intestine are fully preserved in organ culture.

Amphibian intestinal brush border membranes-I. Isolation from Rana catesbeiana tadpole

1. Intestinal brush border membrane vesicles have been isolated form Rana catesbeiana tadpole. 2. Electron microscopy of brush border membrane vesicles demonstrates a fairly homogenous preparation of vesicles, some of them still containing electron dense material. 3. The dense vesicles probably comprise both microvillus core and membrane. 4. Negative staining of vesicles reveals the presence of knob-like structures (particles) covering the outer surface of the membrane. 5. The membranous fraction is characterized by a high specific activity of alkaline phosphatase, trehalase, glucoamylase, maltase and gamma-glutamyltranspeptidase.

Organ culture of adult mouse intestine IV. Stimulation of glucose-6-phosphatase in vitro

Explants of adult mouse jejunum have been maintained in organ culture with or without fructose added to the medium in order to stimulate the intestinal glucose-6-phosphatase (G-6-Pase). When the fructose is added, at the beginning of the culture, a three-fold increase of G-6-Pase in measured during the first 24 h. If the fructose is added after 24 h of culture, no significant increase of the G-6-Pase is registered in comparison with the controls. Proteins, DNA content and dissacharidase activities are not modified during the culture. Alkaline phosphatase activity presents a twofold increase in the controls and stimulated explants. The ultrastructural localization of the G-6-Pase is not altered during the culture.

IgG versus albumin for measurement of plasma volume in normal and hypertensive men

Labeled IgG was evaluated versus labeled albumin for measurement of plasma volume, to see whether it would give a smaller initial dilution volume (indicating a smaller premixing extravascular loss of label) and a smaller difference between initial dilution volume and dilution volume at time 10 min (indicating a negligible extravascular loss in the first 10 min after mixing). IgG was found to have a lower transcapillary escape rate than albumin (P less than 0.01) in eight normal volunteers and in eight hypertensive subjects, hypertension being associated with an increased transcapillary escape of both proteins. Despite this, the dilution volumes obtained were indistinguishable and the need for a correction through a retropolation procedure was the same with both proteins. Albumin and IgG dilution volumes were highly correlated in 21 subjects (r=0.977) so that use of labeled IgG is a proper alternative to use of labeled albumin for plasma volume determination. However, since IgG brings no consistent advantage, labeled albumin remains the best available tracer for that purpose.