Isolation of an attenuated myxoma virus field strain that can confer protection against myxomatosis on contacts of vaccinates

Twenty MV strains obtained from a survey of field strains currently circulating throughout Spain were analyzed for their virulence and horizontal spreading among rabbits by contact transmission. A virus strain with suitable characteristics to be used as a potential vaccine against myxomatosis in wild rabbit populations was selected. Following inoculation, the selected MV strain elicited high levels of MV specific antibodies and induced protection of rabbits against a virulent MV challenge. Furthermore, the attenuated MV was transmitted to 9 out of 16 uninoculated rabbits by contact, inducing protection against myxomatosis.

[Transmissible spongiform encephalopathies in animals]

INTRODUCTION

The transmissible spongiform encephalopathies affect several species of higher animals apart from man. Amongst these, undoubtedly the best known is that affecting cattle, since the association between consumption of beef and its derivatives and the appearance of a variant of Creutzfeldt-Jakob disease in humans has been established.

DEVELOPMENT

This type of pathology has been well known for many years in the ovine family, particularly in sheep and goats. In spite of the establishment of hypotheses linking the cause of the appearance of spongiform encephalopathy in cows with an interspecies jump of the disease between the ovine and bovine families, this has not yet been proved. Concomitant with the epidemic of bovine spongiform encephalopathy, other species of animals were reported to have been affected by an identical disease. These included farmed mink, deer, elks, cats and two species of exotic African ungulates (the nyala and the greater kudu). All cases were described in animals kept in captivity for human consumption. Thus it would seem that there was a common cause of the disease in all cases.

CONCLUSION

In this paper we describe the most relevant aspects of the appearance of this disorder in animals, including the symptoms, epidemiology and pathology typical of each specific condition.

Effect of estrogen-progestin replacement therapy on plasma lipids and lipoproteins in postmenopausal women

Serum levels of cholesterol (Chol), triglycerides (TG), low-density lipoprotein cholesterol (LDL) high-density lipoprotein cholesterol (HDL), both apolipoproteins A1 and B (Apo A1, Apo B), follicle-stimulating hormone (FSH) luteinizing hormone (LH), estradiol (E2), progesterone (P), testosterone (T) and steroid hormone binding globulin (SHBG) were measured in postmenopausal women, before and after four different estrogen-progestin replacement therapies. Each woman was her own control to avoid genetic or socioeconomic differences. Our results showed that serum E2 and TG significantly increased and serum FSH, LH, LDH, Apo B, and Chol significantly decreased after all treatments. Serum P and T did not significantly change after any of the treatments. HDL, Apo A1 and SHBG significantly increased in the groups treated with medroxiprogesterone acetate (MPA) but not in the group treated with Norgestrel. We conclude that estrogen-progestin replacement therapy in postmenopausal women leads to profound and beneficial changes in plasma lipids and lipoproteins and that treatments with cyclic or continuous MPA could provide greater protection against coronary heart disease (CHD).

Imported histoplasmosis in Spain

Histoplasma capsulatum is a dimorphic fungus endemic in the American continent but not in Europe, where cases are usually imported. Its favorite habitat is in warm humid soils. Guano from birds and bats enhance the sporulation of the mycelial phase.1 Man acquires H. capsulatum through inhalation of spores. Most people infected by this fungi remain asymptomatic, but around 10-50% can start an illness ranging from acute pulmonary histoplasmosis to chronic histoplasmosis. In both, there is close clinical resemblance to pulmonary tuberculosis. Immunodepressed patients undergo a more severe form of the disease, usually presenting in the acute disseminated form. We present seven immunocompetent patients with histoplasmosis acquired after traveling to several American countries.

Horizontal transmissible protection against myxomatosis and rabbit hemorrhagic disease by using a recombinant myxoma virus

We have developed a new strategy for immunization of wild rabbit populations against myxomatosis and rabbit hemorrhagic disease (RHD) that uses recombinant viruses based on a naturally attenuated field strain of myxoma virus (MV). The recombinant viruses expressed the RHDV major capsid protein (VP60) including a linear epitope tag from the transmissible gastroenteritis virus (TGEV) nucleoprotein. Following inoculation, the recombinant viruses induced specific antibody responses against MV, RHDV, and the TGEV tag. Immunization of wild rabbits by the subcutaneous and oral routes conferred protection against virulent RHDV and MV challenges. The recombinant viruses showed a limited horizontal transmission capacity, either by direct contact or in a flea-mediated process, promoting immunization of contact uninoculated animals.

Paradoxical behavior of the QT interval during exercise and recovery and its relationship with cardiac memory

BACKGROUND

Few studies have dealt with the behavior of the corrected (QTc) and uncorrected QT intervals during exercise and recovery.

HYPOTHESIS

Based on previously published dynamics of the QT interval during treadmill testing, this study attempted to reevaluate the computer-proposed underlying mechanisms of these dynamics and to determine whether the so-called memory phenomenon could be operative in some subjects without evidence of structural heart disease.

METHODS

This study included 42 unmedicated healthcare volunteers, 23 men and 19 women aged between 20 and 42 (mean 31.7) years. All had normal physical examinations, x-rays, and transthoracic echocardiograms. The electrocardiograms were also normal with 12-lead QT interval dispersions of < 90 ms.

RESULTS

During exercise and recovery, the behavior of the QT intervals permitted the categorization into two groups. In Group 1 (31/42; 73.8% of subjects) the uncorrected QT interval showed a biphasic pattern consisting of a gradual decrease during incremental exercise followed by a gradual increase during recovery. In contrast, the QTc interval had a triphasic pattern resulting from a slight increase during the early phase of exercise, a gradual decrease at the highest rates, and a final increase during recovery as the rate slowed to control values. In Group 2 (11/42; 36.2% of subjects) the behavior was considered as paradoxical since the uncorrected QT interval displayed in a triphasic pattern whereas the QTc interval yielded a tetraphasic pattern due to the fact that both showed a second decrease during recovery while the rate was decreasing.

CONCLUSIONS

Analysis of dynamics behavior of the QTc and the uncorrected QT intervals during exercise showed that some normal subjects had a paradoxical behavior which, because of its temporal relation to the phases of exercise, could be an expression of the so-called memory phenomenon.

Streptococcus pneumoniae bacteremia in a community hospital

We reviewed 71 consecutive patients with Streptococcus pneumoniae bacteremia. The patients were analyzed by age, sex, ethnic background, and clinical presentation. Laboratory data reviewed included a CBC count, electrolyte levels, liver function studies, chest radiograph, HIV status, a sputum culture and Gram's stain, and sensitivities for the S pneumoniae isolated. Modalities of therapy, response to treatment, and ultimate outcome were examined. Many of the patients with pneumococcal bacteremia did not have cough, fever, or chills. HIV positivity was a risk factor for pneumococcal infection although it was not associated with increased mortality. Mortality correlated with elderly status, leukopenia, and lack of fever. Many patients had symptoms suggestive of atypical pneumonia including myalgia and mental status change. Hyponatremia and hyperbilirubinemia were commonly noted.

On the limits of enhancement in human gene transfer: drawing the line

Enhancement-line human genetic engineering has recurrently been targeted for bioethical discussion and is usually (if not always) illustrated by examples alluding to a genetic technology that is far beyond our current possibilities. By discussing an ambitious project related to solid tumor cancers--multidrug resistance (MDR)--the present paper places the question on a more realistic plane and draws bioethical conclusions to serve as guidelines in the field. The paper also establishes the inadequacy of the prevalent concept of genetic medicine as one of substitution.

Saline wound irrigation reduces the postoperative infection rate in guinea pigs

Wound irrigation with saline is widely used alone or together with systemic antibiotic prophylaxis to prevent postoperative wound infection. This study was aimed to investigate the effect of saline irrigation upon the bacterial load on wound surfaces and on the wound infection rate in an animal model. In 16 guinea pigs, two wounds were contaminated with Bacteroides fragilis and Escherichia coli. One wound was irrigated with saline, while the other received no prophylaxis. Quantitative wound cultures were performed before and after irrigation. The wound infection rate was determined at 10 days. Saline irrigation reduced the aerobic and anaerobic bacterial counts in wound margins. The infection rate was also reduced (15/16 nonirrigated vs 6/16 irrigated, P < 0.001). High bacterial counts at the end of operation were associated with wound infection (P < 0.001). At skin closure, wounds which later became infected harbored fourfold more bacteria than noninfected wounds [8.7 (6.4- 1 1.0) vs 2.3 (0.8-3.7) colony-forming units x 10(3) of E. coli/cm2; P < 0.005]. Saline wound irrigation diminishes infection rate in experimental animals by means of a significant reduction of the bacterial inoculum present at the time of skin closure.

Tropism of human adenovirus type 5-based vectors in swine and their ability to protect against transmissible gastroenteritis coronavirus

The infection of epithelia] swine testicle and intestinal porcine epithelial (IPEC-1) cell lines by adenovirus type 5 (Ad5) has been studied in vitro by using an Ad5-luciferase recombinant containing the firefly luciferase gene as a reporter. Porcine cell lines supported Ad5 replication, showing virus titers, kinetics of virus production, and luciferase expression levels similar to those obtained in human 293 cells, which constitutively express the 5'-end 11% of the Ad5 genome. The tropism of Ad5-based vectors in swine and its ability to induce an efficient immune response against heterologous antigens expressed by foreign genes inserted in these vectors has been determined. Ad5 vectors replicate and express heterologous antigens in porcine lungs and mediastinal and mesenteric lymph nodes. Significant levels of heterologous antigen expression were also demonstrated in the small intestine (jejunum and ileum), but Ad5 replication in this organ was very poor, suggesting that Ad vectors undergo an abortive replication in the porcine small intestine. The tissues infected by Ad5 were dependent on the inoculation route. The oronasal route appeared to be best for inoculation of bronchus-associated lymphoid tissue infection, while the intraperitoneal route was best for gut-associated lymphoid tissue infection. Epithelial cells of bronchioles, macrophages, type II pneumocytes, and follicular dendritic cells were identified as targets for Ad5, while epithelial cells of the intestine were not infected by Ad5. Viruses with a deletion from 79.5 to 84.8 map units in the E3 region, with or without heterologous inserted genes, replicated to lower levels in porcine tissues than did wild-type Ad5. It was also shown that an Ad5 recombinant expressing the four antigenic sites (A, B, C, and D) of transmissible gastroenteritis coronavirus (TGEV) spike protein induced in swine immune responses which neutralized TGEV infectivity. In addition, porcine serum from Ad-TGEV-immune animals provide passive protection when mixed with fully virulent TGEV and orally administered to highly susceptible newborn piglets. These results taken together indicate that swine may be a good animal model for human Ad5 lung infection to aid in the evaluation of candidate adenovirus vaccines and that Ad5 may be suitable as a recombinant viral vaccine or for other applications in swine.

[Hyponatremia as a complication of laparoscopic hysterectomy. Report of a case]

The case of a 42 years old woman, who had laparoscopic hysterectomy and seven hours after presented with a convulsive crisis and later a coma status, secondary to hyponatremia. Hyponatremia causes, are discussed, as well as its relationship with syndrome of inadequate secretion of antidiuretic hormone, diagnosis, management, prognosis factors and risk.

Induction of antibodies protecting against transmissible gastroenteritis coronavirus (TGEV) by recombinant adenovirus expressing TGEV spike protein

Ten recombinant adenoviruses expressing either fragments of 1135, 1587, or 3329 nt or the full-length spike gene of transmissible gastroenteritis coronavirus (TGEV) have been constructed. These recombinants produce S polypeptides with apparent molecular masses of 68, 86, 135, and 200 kDa, respectively. Expression of the recombinant antigen driven by Ad5 promoters was inhibited by the insertion of an exogenous SV-40 promoter. Most of the recombinant antigens remain intracytoplasmic in infected cells. All the recombinant-directed expression products contain functional antigenic sites C and B (Gebauer et al., 1991, Virology 183, 225-238). The recombinant antigen of 135 kDa and that of 200 kDa, which represents the whole spike protein, also contain antigenic sites D and A, which have previously been shown to be the major inducers of TGEV-neutralizing antibodies. Interestingly, here we show that recombinant S protein fragments expressing only sites C and B also induced TGEV-neutralizing antibodies. The chimeric Ad5-TGEV recombinants elicited lactogenic immunity in hamsters, including the production of TGEV-neutralizing antibodies. The antisera induced in swine by the Ad5 recombinants expressing the amino-terminal 26% of the spike protein (containing sites C and B) or the full-length spike protein, when mixed with a lethal dose of virus prior to administration to susceptible piglets, delayed or completely prevented the induction of symptoms of disease, respectively.

Neurotrophin receptor proteins immunoreactivity in the rat cerebellar cortex as a function of age

The influence of age on immunohistochemically demonstrable neurotrophin receptor proteins (p75, trkA-, trkB-, and trkC-proteins) was studied in the cerebellar cortex of Wistar male rats aged 3 (young), 12 (adult) and 24 (old) months. The number of Purkinje neurons displaying p75, trkA- and trkC-like proteins immunoreactivity (IR), as well as the intensity of p75 and trkA-like protein IR, were significantly reduced in aged rats in comparison with 3 and 12-month-old rats. The intensity of trkC-like protein in the cytoplasm of Purkinje neurons remained unchanged for all the period studied. Moreover, no significant age-dependent changes were observed in the density of p75 or trkC-like proteins IR in the granule neurons layer. The molecular layer showed faint p75 IR which decreased as a function of age. No immunolabelling for neuronal trkB-like proteins was observed, but trkB- and trkC-like proteins IR was found in non-neuronal cells. These results suggest that cerebellar cortex neurons are responsive to and/or dependent upon different neurotrophins. Moreover, the age-dependent impairment in the expression of some neurotrophin receptors in Purkinje neurons, but not in the granule neurons, lends support to a role for neurotrophins in cerebellar aging.

Calbindin D-28k immunoreactivity in the rat cerebellar cortex: age-related changes

The present study was designed to analyze age-dependent changes in the expression of calbindin D-28k immunoreactivity in the cerebellar cortex of male Wistar rats aged 3 months (young), 12 months (adult) and 24 months (old). Calbindin D-28k immunoreactivity was localized primarily in the cytoplasm of Purkinje neurons and in the basal portion of their dendritic processes entering in the molecular layer. The expression of calbindin D-28k immunoreactivity was highest in Purkinje neurons of adult rats and lowest in Purkinje neurons of old rats. Moreover, the number of Purkinje neurons displaying calbindin D-28k immunoreactivity was decreased in aged rats. These results demonstrate the occurrence of age-related-changes in the expression of immunoreactivity of the Ca2+ binding protein calbindin D-28k in the rat cerebellar cortex. The possibility that impairment in the expression of Ca2+ binding proteins may be involved in changes of intracellular Ca2+ homeostasis reported in aging and in some neuro-degenerative disorders is discussed.

Endocytosis of three serum proteins of a multigene family and of arachidonic acid in human lectin-stimulated T lymphocytes

Alpha-fetoprotein (AFP), serum albumin (SA), and vitamin D binding protein (DBP) are members of a multigene family of proteins showing high structural homology. AFP and SA exhibit a reciprocal relation during development and carry mostly fatty acids, while DBP carries vitamin D and its metabolites in the plasma. Covalent conjugates of these proteins with horseradish peroxidase (HRP) were used to follow by cytochemistry, at the electron microscope level, the protein uptake and intracellular pathways in peripheral blood human lymphocytes stimulated to blast formation by phytohemagglutinin (PHA). Transferrin (Tf), an iron-binding plasma protein, was used as a control. Combined with the results of competition and saturability experiments reported elsewhere, the ultrastructural observations are in favour of a specific endocytosis of the four proteins through cell surface receptors. Tf and AFP enter the cells via small vesicles and endosomes and move to multivesicular bodies (MVBs) and tubular vesicular elements located in the Golgi-centrosphere region to be finally recycled back into the medium. A noncovalent conjugate of AFP-HRP with 3H arachidonic acid [3H-(20:4)] is strongly internalized at 37 degrees C in PHA-stimulated lymphocytes; the autoradiographic labelling, localized in cellular membranes and mostly in lipid droplets, was only occasionally associated with organelles where the presence of AFP-HRP was cytochemically detected. SA, which competes with AFP for a common binding site on the surface of activated T cells, is endocytosed through small vesicles, endosomes, and MVBs before being released in a degraded form from the cells, in agreement with the localization of SA-HRP in lysosome-like organelles. DBP-HRP is poorly internalized through noncoated vesicles, endosomes, and MVBs and is finally routed to lysosomes. The physiological role of AFP and SA would be to mediate the transfer of fatty acids into cells, while that of DBP would be to facilitate the intracellular delivery of vitamin D.

Carrier-protein-mediated enhancement of fatty-acid binding and internalization in human T-lymphocytes

Albumin and alpha-fetoprotein (AFP) are members of a multigene family which also includes vitamin-D-binding protein. Previous work in our laboratory has provided experimental support for the suggestion that the entry of unsaturated fatty acids into growing, normal and neoplastic cells may be regulated by AFP. In the actual study we have examined the role of human serum albumin (HSA) as a carrier protein, when compared to AFP, on the uptake (binding and internalization) of fatty acids by resting and PHA-activated human lymphocytes. Radioiodinated human HSA and tritiated oleic and arachidonic acids were used under different experimental conditions to follow the binding of the protein and fatty acids (FA) to cells. Time-course uptake at 4 degrees C of HSA and of oleic and arachidonic acids bound to HSA (FA/HSA molar ratio = 1) by either resting or activated T-lymphocytes exhibited a steady state of binding. The amount of FA bound was much greater than the corresponding amount of HSA, suggesting that T-lymphocytes bear distinct binding sites for albumin and fatty acids. A saturable process of FA binding was observed at constant unbound FA concentration in the incubation medium when the HSA-to-FA molar ratio was fixed at 1 and the concentrations of both HSA and FA were increased simultaneously. This saturable component of binding reflects an intrinsic regulatory effect of HSA, probably operating throughout the interaction of the protein with specific cell receptors. At varying unbound FA concentrations, binding curves showed two distinct components: a non-linear portion which could indicate the presence of a saturable process operating at low concentrations of unbound, free FA, followed by a second part which increased linearly with the concentration of unbound FA. The amount of FA bound at 4 degrees C and bound and internalized at 37 degrees C by both types of cell was considerably higher in the presence than in the absence of carrier proteins. On the contrary, carrier proteins were without effect on the distribution pattern of internalized oleic or arachidonic acid. Taken together, these observations suggest that: (i) the binding and entry of FA into cells is enhanced by the two carrier-proteins at low concentrations of free, unbound fatty acids in the vicinity of the cell surface, and (ii) fatty-acid uptake seems regulated by a dual-receptor mechanism involving HSA and/or AFP receptors as well as plasma-membrane FA-binding proteins.

[Laparoscopic hysterectomy. Initial experience]

The results of the first twelve cases of Laparoscopic Assisted Vaginal Hysterectomy, are presented. The indications for hysterectomy were myomatosis, suspicion of adenomyosis and endometriosis. The surgical technique is described in detail in which a combination of bipolar Kleppinger forceps and reusable scissors were employed. There were two intraoperative accidents. One subcutaneous emphysema of the left half of the abdominal wall, thorax, neck, face and upper limb. The second case was a damage to a branch of the left epigastric artery. The average time was 4 hours 31 minutes which includes 9 patients to which another surgical procedure was practiced. There was no significant bleeding in any of the patients. The postoperative complications were 1 hyponatremia that needed the use of an Intensive Care Unit and the other was periumbilical hematoma of 3 cm. of diameter. The patient was discharged on the one to three postoperative day with an average of two days. The average hospital fee was 35% higher than an abdominal hysterectomy. All the surgery were videotaped and later viewed by the patients. It was concluded that the laparoscopic assistance that is offered to the vaginal hysterectomy is particularly advantageous for hysterectomy especially in the cases where absence of genital prolapse, when uni or bilateral Adnexectomy is required, previous past history of abdomino-pelvic surgery, endometriosis and adhesions. This procedure should be included in the armamentarium of the Gynecological Surgeons but only after and appropriate training.

Membrane proteins from lymphoblastoid cells showing cross-affinity for alpha-fetoprotein and albumin. Isolation and characterization

AFP or SA immobilized on nitrocellulose membranes (AFP-NC or SA-NC) were used as affinity matrices to purify cell membrane proteins with affinity for AFP (AFP-BP) and for SA (SA-BP) from membrane-enriched extracts of Raji cells (a B-lymphoma cell line), as well as for normal resting and activated peripheral blood lymphocytes (PBMC). SDS-PAGE and ligand blotting assays showed that AFP-BP and SA-BP isolated from Raji cells are probably identical molecules. They consisted of two sets of polypeptides of 31 kDa and 18 kDa. The glycoprotein nature of isolated 31 kDa and 18 kDa peptides was suggested by positive staining with Schiff's reagent, and amino-acid analysis revealed similar amino-acid composition for the two glycoproteins. In human PHA-activated PBMC, only the 18 kDa polypeptide was identified and isolated as AFP-BP or SA-BP. As in Raji cells, this 18 kDa polypeptide, isolated by affinity for AFP or for SA, appeared to be the same molecule. Contrary to Raji cells and activated PBMC, no proteins with an affinity for AFP or for SA were identified or isolated in resting PBMC. These observations strongly suggest that the isolated 31 kDa and 18 kDa glycoproteins are probably AFP receptors previously demonstrated in several neoplastic and normal cells undergoing growth and/or differentiation; indeed, they were identical to albumin-binding proteins described by others.

Evaluation of eight serological tests in the diagnosis of human echinococcosis and follow-up

The ELISA with use of IgG, IgA, and IgE, latex agglutination, indirect hemagglutination (IHA), total IgE, the radioallergosorbent test (RAST), and immunoelectrophoresis (IEP) were carried out to determine the preoperative diagnosis of infection due to Echinococcus granulosus in 131 patients. Eighty-nine patients received follow-up care for 42 +/- 22 months (mean +/- SD); 72 were treated surgically and 17 with mebendazole only. We analyzed 5 +/- 2 serum samples per patient and analyzed each serum sample using the eight tests. IgG ELISA was the most sensitive (up to 94%) and specific (up to 99%) test for the majority of cyst locations in the patient. IEP was positive in only 73% of cases. The combination of IgG ELISA, IHA, and IgA ELISA allowed us to achieve a sensitivity of 81% in cases of pulmonary echinococcosis. IgE and IgA were both responsible for most nonspecific reactions, the former in patients with parasitic diseases other than echinococcosis and the latter in patients with cirrhosis of the liver and malignancies. IgG ELISA and IHA were the most adequate tests for postsurgical follow-up. In patients with favorable clinical outcome, the specific IgG level decreased early toward the end of the first year, although serological positivity could persist beyond 6 years. A rise of IgG level 2 or 3 years after treatment suggested persistent active infection. In patients with mebendazole-associated cure, only tests with total or specific IgE detection seemed to exhibit a strong association with decreasing levels or with negative results.

In vitro and in vivo studies with flutrimazole, a new imidazole derivative with antifungal activity

1-[(2-Fluorophenyl)(4-fluorophenyl)phenylmethyl]-1H-imidazole (flutrimazole, UR-4056, CAS 119006-77-8) is a new topical imidazole antifungal agent which displays potent broad-spectrum in vitro activity against dermatophytes, filamentous fungi and yeasts, saprophytic and pathogenic to animals and humans (MIC = 0.025-5.0 micrograms/ml). In most of these studies the activity of flutrimazole was comparable to that of clotrimazole and markedly higher than that of bifonazole (MIC differences of greater than or equal to 1 order of magnitude). Tested against Scopulariopsis brevicaulis (8 strains), both flutrimazole and clotrimazole exhibited fungistatic and fungicidal activity, and clotrimazole appeared something less active (MIC = 0.3-2.5 micrograms/ml) than flutrimazole (MIC = 0.15-0.6 micrograms/ml). In animal experiments, topical application of 1% and 2% flutrimazole, as a cream or solution, was highly effective in models of rat vaginal candidiasis and guinea-pig trichophytosis, giving a rate of cured or cured plus markedly improved animals higher than 80%. Flutrimazole shares the mode of action of other imidazole or triazole-containing antifungals, i.e. inhibition of fungal lanosterol 14 alpha-demethylase, as it strongly inhibits ergosterol biosynthesis in a cell-free homogenate of Candida albicans, with an IC50 value of 0.071 mumol/l.