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J Vidal

Publications and source records attributed to J Vidal.

At least 73 records · Page 4Linked to original sources
PubMed2000

[Cerebral amyloid angiopathy presenting as a pseudotumor: 2 cases with spontaneously favorable outcomes].

A rare clinical and radiographical presentation of cerebral amyloid angiopathy mimicking a brain neoplasm was observed in 2 patients. The signs and symptoms included seizures and focal parieto-occipital dysfunction in 1 case, massive left hemisphere dysfunction and akinetic mutism in the other. Brain CT and MRI showed nonspecific focal white matter abnormalities suggestive of the diagnosis of low-grade glioma. Gradient echo T1 and T2-weighted images showing multiple areas of signal void suggesting multiple disseminated petechial hemorrhages led to the diagnosis of cerebral amyloid angiopathy. An eventless brain biopsy confirmed the diagnosis. The neuropathology examination disclosed amyloid angiopathy of the pial and cortical vessels selectively stained by anti A-beta protein antibodies. The clinical course was remarkable in the two cases with almost complete clinical recovery without any particular treatment.

Aged↗
PubMed2000

Role of the phosphoinositide pathway in the light-dependent C4 phosphoenolpyruvate carboxylase phosphorylation cascade in Digitaria sanguinalis protoplasts.

Stimulus-response coupling in animal cells frequently involves the hydrolysis of PtdIns(4,5)P(2) which is catalysed by phosphoinositide-specific phospholipase C (PI-PLC). There is an increasing body of evidence for PI-PLC-based signalling in plant cells; however, the physiological role of this system remains poorly documented in plants. Our data provide the first evidence that a PI-PLC-based signalling system is a committed step in the transduction chain controlling the phosphorylation state of C(4) phosphoenolpyruvate carboxylase (PEPC), the regulation of which is central to the assimilation of atmospheric CO(2) in C(4) plants.

Calcium↗
PubMed1999

[Changes in seroepidemiology of hepatitis A virus infection in Catalonia in the period 1989-1996. Implications for new vaccination strategy].

BACKGROUND: The aim of this study was to investigate the prevalence of the risk factors of hepatitis A virus infection (HAV) in a representative sample of a Catalonian population obtained from 1995 to 1996 and the changes in the prevalence of this infection over the period of 1989-1996. SUBJECTS AND METHODS: The prevalence of anti-HAV was determined by an ELISA test in a randomized sample of 2,142 individuals, 884 from 6 to 14 years of age and 1,248 over the age of 15 years. The results were related to sociodemographic variables and multiple logistic regression analysis was performed to establish which variables were related to the risk of infection. RESULTS: The global prevalence of HAV infection was 67.8%. The prevalence of HAV infection increased from 3.5% in the group from 5-14 years of age to 99% in that over the age of 64 years (p < 0.001). A higher prevalence was observed in those born outside of Catalonia (odds ratio [OR] = 3.97; 95% CI, 2.4-6.4) and in those with a lower level of education (OR = 2.60; 95% CI, 1.9-3.5). In the period 1989-1996 the prevalence of the infection has decreased in the population under the age of 45, the differences being statistically significant in the age groups 10-14 (p < 0.0001) and 25-34 (p < 0.0001). CONCLUSIONS: The prevalence of HAV infection has progressively decreased in Catalonia while it proportionally increases the susceptible population under the age of 45 years. These findings may be important in the design of strategies for the prevention of HAV infection with universal vaccination programs against this disease.

Adolescent↗
PubMed1999

Measles immunity and vaccination policy in Catalonia.

The prevalence of antibodies against measles in a representative sample of the school population in Catalonia was established and the results compared with previous studies. The study was carried out in 1996 using blood samples obtained from schoolchildren aged 6-7 years, 10-11 years, 13 14 years and 15-16 years. 1231 schoolchildren were studied. The global prevalence of antibodies was 96.3%, and a considerable increase was observed with respect to the prevalence in 1986 (89.4%). The level of antibodies was 94% at 6-7 years and 10-11 years, 99.7% at 13-14 years and 98.3% at 15 16 years. These data would suggest the advancement of the administration of the second dose of measles-mumps rubella vaccine to 4 6 years instead of at 11 years.

Adolescent↗
PubMed1999

Prevalence and mother-to-infant transmission of hepatitis viruses B, C, and E in Southern Tanzania.

Hepatitis B and C markers were tested in 980 pregnant women, in the infants born to infected mothers, and in a random sample of 42 and 50, respectively, children born to uninfected mothers in Tanzania. Sixty-two women (6.3%) were positive for HBsAg and 15 (24%) were HBeAg-seropositive. Anti-HCV was detected in 49 women (5%), 15 (31%) of whom had detectable viremia. HCV RNA serum levels were low and only genotype 4 was identified. Sixty-six women (6.7%) were positive for anti-HIV, six of whom were coinfected with HBV and one with HCV. Anti-HEV was negative in the 180 women tested. At 8 months of age, HBsAg was detected in 8% and 2% of children born to HBV-infected and noninfected mothers, respectively (P = 0.2). Corresponding figures at 18 months of age were 31% and 21% (P = 0.3). When tested at 2 months of age, HCV RNA was not detected in any of the 43 children born to anti-HCV-positive mothers nor in any of 50 children born to anti-HCV-negative mothers. At 18 months, only one child, born to an anti-HCV-positive mother, had detectable HCV RNA. None of the infants born to women with HIV coinfection were infected with hepatitis viruses. This study suggests that exposure to HEV does not occur in southern Tanzania. The prevalence of current HBV infection in pregnant women from rural Tanzania is lower than in other sub-Saharan areas. In early childhood, HBV infection appears to occur by horizontal rather than maternofilial mechanisms of transmission. The prevalence of HCV infection is similar to that in other African countries. The results of this study show for the first time in Africa that mother-to-infant transmission does not play a significant role in the acquisition of HCV infection.

Adolescent↗
PubMed1999

Cryopreserved arterial homografts: preliminary results in infrageniculate arterial reconstructions.

The aim of this report is to present our preliminary experience using cryopreserved arterial homografts in below-knee revascularization. We carried out a retrospective study at the Public Health Hospital of the Servicio Galego da Saude (SERGAS) from October 1995 to March 1997 in which cryopreserved arterial homografts were used for revascularization of 17 lower limbs in 16 patients. The clinical indications were limb-threatening ischemia in 15 lower extremities (7 with rest pain and 8 with ischemic ulcers or gangrene), and large aneurysms of femoropopliteal arteries in 2. In addition, 75% of the patients had undergone previous surgical procedures for revascularization on the involved extremity. No patient had a suitable greater saphenous vein in the ipsilateral extremity and all patients required a below-knee arterial reconstruction procedure. There was just one runoff vessel in 11 of 17 extremities (65%). A histological exam was performed in four patients who died (1 case) or had homograft-related complications (3 cases). The results of this study indicated that cryopreserved arterial homografts could be a promising alternative when below-knee revascularization is required in patients lacking suitable greater saphenous vein, especially in those with limited life expectancy, but despite early acceptable results, many aspects must be clarified. Close follow-up is mandatory.

Aged↗
PubMed1999

Influence of the specific immune response on some consistent murine behaviors.

The author's goal was to discover if the generation and maintenance of the specific immune response resulted in alterations of reliable behaviors (i.e., behaviors correlated over time). The behaviors (ambulation, rearing, and interaction with a conspecific) of CD1 male mice were measured in a small open field, and several days later, the mice were immunized with antigens (either splenocytes from C57BL/6 mice or a mixture of sheep erythrocytes and goat serum). The same behaviors were recorded again some hours, or some days, after immunization. Immunizations and behavioral measurements were repeated at various intervals. Blood levels of antibodies to the antigens were measured 6 days after immunization. The recorded behaviors were consistent (according to Kendall coefficient of concordance). The mice mounted antibody responses to the antigens, yet no behavioral changes were apparent during the response. On the contrary, a single injection of E. coli lipopolysaccharide decreased ambulation and rearing. It is proposed that in healthy mice kept in normal conditions, the specific immune response may be unrelated to reliable behavioral changes.

Animals↗
PubMed1999

Triplet pregnancy achieved through intracytoplasmic sperm injection with spermatozoa obtained by prostatic massage of a paraplegic patient: case report.

Spinal cord-injured men with ejaculation disorders can have children thanks to assisted reproduction techniques. Spermatozoa from these patients are usually obtained through vibratory stimulation, electroejaculation or by puncturing the seminal duct or the testicle. We present the first published case, as far as we are aware, of spermatozoa obtained through prostatic massage of a paraplegic patient. Penile vibratory stimulation was unsuccessful in this patient. In-vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI) with spermatozoa obtained through electroejaculation was performed at another centre but pregnancy was not achieved. Through prostatic massage, we obtained a total semen volume of 6 ml containing a total count of 12.32x10(6) spermatozoa (6.24x10(6) with tails), 8% of which had motility (graded + and ++); and 16% of which had normal morphology. The spermatozoa obtained were then used to perform IVF with ICSI and a triplet pregnancy was achieved. Prostatic massage appears to be an easy, non-traumatic and risk-free method to obtain spermatozoa from paraplegic patients.

Adult↗
PubMed1999

Evidence for a slow-turnover form of the Ca2+-independent phosphoenolpyruvate carboxylase kinase in the aleurone-endosperm tissue of germinating barley seeds

Phosphoenolpyruvate carboxylase (PEPC) activity was detected in aleurone-endosperm extracts of barley (Hordeum vulgare) seeds during germination, and specific anti-sorghum (Sorghum bicolor) C4 PEPC polyclonal antibodies immunodecorated constitutive 103-kD and inducible 108-kD PEPC polypeptides in western analysis. The 103- and 108-kD polypeptides were radiolabeled in situ after imbibition for up to 1.5 d in 32P-labeled inorganic phosphate. In vitro phosphorylation by a Ca2+-independent PEPC protein kinase (PK) in crude extracts enhanced the enzyme's velocity and decreased its sensitivity to L-malate at suboptimal pH and [PEP]. Isolated aleurone cell protoplasts contained both phosphorylated PEPC and a Ca2+-independent PEPC-PK that was partially purified by affinity chromatography on blue dextran-agarose. This PK activity was present in dry seeds, and PEPC phosphorylation in situ during imbibition was not affected by the cytosolic protein-synthesis inhibitor cycloheximide, by weak acids, or by various pharmacological reagents that had proven to be effective blockers of the light signal transduction chain and PEPC phosphorylation in C4 mesophyll protoplasts. These collective data support the hypothesis that this Ca2+-independent PEPC-PK was formed during maturation of barley seeds and that its presumed underlying signaling elements were no longer operative during germination.

Journal Article↗
PubMed1999

Effect of reduced immunity on murine behaviors.

Reduction of immunity in 11 mice of the CD1 strain by administration of methotrexate did not alter some reliable behaviors in the open-field (ambulation, rearing, defecation) compared with 10 matched mice injected with saline. Perhaps moderate depression of immunity may not affect some characteristic behaviors.

Animals↗
PubMed1999

[Postero-lateral surgical approach to soft cervical herniated discs. Technical note].

Most ruptured cervical discs are operated on by an anterolateral approach. The posterior approach is an older procedure, nowadays underused because it was associated with a high morbidity, especially in terms of medullary complications. However, posterior approach has evolved in posterolateral route, which is not so devastating and has a very low morbidity rate. It gives excellent functional results when surgery is dedicated to monoradiculopathy from soft posterolateral cervical hernias. It seems appropriate to consider this surgical route as an alternative to anterolateral surgery in these very selected cases. The authors describe and comment the technique.

Cervical Vertebrae↗
PubMed1999

Use of a shape-memory alloy (nitinol) in a removable prostate stent.

An easily removable prostate stent would be useful in various clinical situations but is not currently available. Thus, we studied the safety, tolerability, and ease of removal of a nitinol (nickel-titanium alloy) prostate stent in 10 men with symptomatic benign prostatic hyperplasia. The circular-coil stent becomes hourglass in shape following deployment, with the narrowest diameter approximately 35F. A working hypothesis was that the temperature-sensitive shape memory of nitinol would allow for its easy removal vis-à-vis other available stents. Using several modifications of a prototype insertion device, we found that the nitinol stents were easily inserted, retained their shape during retention periods of 1 to 4 weeks, caused no gross tissue reaction, and were removed easily with gentle traction after in situ cooling with iced saline lavage. Stent migration was observed in two patients, but otherwise, the stents were well tolerated. Nitinol prostate stents appear to fulfill a theoretical promise of being biologically inert, "superelastic," and pliable when cooled, allowing for easy removal. Further clinical investigation appears warranted.

Aged↗
PubMed1998

[Low level of immune protection against diphtheria in adult population of Catalonia].

BACKGROUND: Seroepidemiologic studies carried out in different European countries have shown the existence of low levels of protection against diphtheria. In this study the prevalence of antidiphtheria antibodies in the adult population of Catalonia, Spain, during 1995 has been studied. PATIENTS AND METHODS: The prevalence of the seroprotection against diphtheria was investigated in a representative sample (n = 1,248) of the adult population of Catalonia aged 15 or older. The antibody levels were determined by means of the in vitro Vero-cell neutralization technique. Two protection levels were considered: 0.01-0.09 U/ml (partial immunity) and > or = 0.1 U/ml (total immunity). RESULTS: The prevalence of absolute seroprotection was 12.4% (CI 95%: 10.5-14.3%) and that of partial and absolute seroprotection was 26.0% (CI 95%: 23.6-28.4%). The prevalence of antibodies is higher in men than in women (29.2% versus 23.1%; p < 0.05), and in urban than in rural environments (27.2% versus 19.9%: p < 0.05). The odds ratios adjusted by multiple logistic regression analysis were 1.43 (1.11-1.85) and 1.56 (1.05-2.29), respectively. CONCLUSION: The prevalence of antidiphtheria antibodies in the adult population of Catalonia, Spain, is low. The results suggest the need to develop antidiphtheria vaccination programmes in the adult population.

Adolescent↗
PubMed1998

Design and synthesis of hydrazinopeptides and their evaluation as human leukocyte elastase inhibitors.

The name hydrazinopeptide designates peptidic structures in which one of the native CONH links is replaced by a CONHNH (hydrazido) fragment. In this paper, we report the synthesis of such hydrazinohexapeptides (3-5) analogous to Z-Ala-Ala-Pro-Val-Ala-Ala-NHiPr (6), a substrate of human leukocyte elastase (HLE; EC 3.4.21.37), cleaved by this serine protease between the Val4 and Ala5 residues. In hydrazinopeptides 3-5, the Ala5, Val4, or Pro3 residue, respectively, of the model peptide, has been replaced by the corresponding alpha-L-hydrazino acid. In 3, the bond likely to be cleaved by HLE is the one involving the CONHNH link, while in 4 and 5, this link is normally shifted away by one or two amino acid units from the catalytic serine. On incubation with HLE, hydrazinopeptide 3 proved to be a substrate and was cleaved between Val4 and NHAla5, like peptide 6. In contrast, 4 and 5 proved to bind to HLE without being cleaved, featuring properties consistent with reversible competitive inhibition. General guidelines for the synthesis of hydrazinopeptides are also reported in this paper. These guidelines take into account the chemical specificity of hydrazino acids, while being fully compatible with the conventional peptide coupling techniques. The utilization of orthogonally bisprotected hydrazino acids 1 where the Nbeta and Nalpha atoms bear a Boc and a Bzl group, respectively, is recommended for the easy construction of such hydrazinopeptides.

Drug Design↗
PubMed1998

[Dengue: a re-emerging disease. A clinical and epidemiological study in 57 Spanish travelers].

Dengue infection is nowadays considered a re-emergent disease. It has a worldwide tropical and subtropical distribution. The dengue virus in a member of the flavivirus family composed by 4 different serotypes. The virus is transmitted by mosquitos of the Aedes genus. With the increment of travels to the endemic areas, dengue is now observed frequently in our country. We analyzed 57 patients, 30 with imported dengue (ID) and 27 with dengue fever suffered during the trip (DDT). This series is compared with other published ones and a review of the subject is presented. Patients with ID followed a protocol as a febril syndrome returning from the tropics. Dengue was diagnosed through a compatible clinico-epidemiological history, the absence of other ferbil illness and positivity of specific serology. All patients had travelled to endemic areas (Central America 28 cases, Indian subcontinent 15, South-East Asia 10, South America 2, West Africa one, and Pacific one). The following were the most important clinical characteristics: fever and asthenia (100%), headache (98%), mialgia (84%), arthralgia (72%), morbilliform rash (61%) and retroocular pain (65%). For ID cases, the most helpful analitical results were: leucopenia (70%), reactive lymphocytes in peripheral blood smear (70%), thrombocytopenia (70%), and increased hepatic enzymes ALAT (53%), ASAT (63%) and LDH (100% in the 7 patients tested for this enzyme). Dengue must be included in differential diagnosis of fever in patients coming back to travels to tropical areas.

Animals↗
PubMed1998

A splice site mutation gives rise to a mutant of the C4 plant Amaranthus edulis deficient in phosphoenolpyruvate carboxylase activity.

The molecular nature of a mutant of the C4 plant Amaranthus edulis that has been shown to contain only 5% of the normal activity and protein of phosphoenolpyruvate carboxylase (PEPC) (Dever et al., 1995) has been investigated. Using Northern blot analysis, it has been shown here that the PEPC transcripts are produced in the mutant. In-vitro translation of these transcripts generated two products immunoprecipitable by a PEPC N-terminus-specific antibody. One of these products has the size of the complete PEPC polypeptide, the other is 9kDa smaller and was not revealed when using a PEPC C-terminus-specific antibody. In the mutant plant, using the same N- and C-terminus-specific antibodies, only the larger polypeptide was immunodetected, whilst at a very low level. A sequence analysis of the suspected faulty region of the mRNA revealed incorrect splicing of the last intron of the PEPC pre-mRNA. Two mis-splicings have been identified, both occurring after an AG site, one leading to a protein lacking five amino acids, the other to a truncated protein due to a stop codon generated by a frame shift in the translation. Finally, the sequencing of the boundary between the last intron and exon showed that these inaccurate splicings result from a mutation in the genuine canonical 3'AG splicing site.

Base Sequence↗
PubMed1998

[Anatomopathological bases of latent ventricular dysfunction in insulin-dependent diabetics].

INTRODUCTION AND OBJECTIVES: The natural history of diabetic cardiomyopathy remains unclear, mainly due to concurrent coronary disease or hypertension. Since the presence of confounding factors is less likely in youngsters, they constitute a suitable study model to analyze early stages of diabetic cardiomyopathy. PATIENTS AND METHODS: We screened 33 young normotensive asymptomatic patients with type I diabetes mellitus. Mean age was 28 +/- 8 y (range 18 to 46 y) and there were 14 men. RESULTS: 2-D Echo showed normal left ventricular size and wall motion in all patients but one. Radionuclide basal ejection fraction was 56.5 +/- 6.6% and increased to 63 +/- 7.4% (p < 0.02) on exercise. According to Rozansky criteria, 16 patients had an abnormal response. Abnormal stress sestamibi was detected in 18 patients and only 3 had reversible defects. Coronary angiography was performed in 11 patients with at least one abnormal non-invasive study response. Coronary angiography revealed normal vessels in all patients and left anterior descending blood flow velocity (Doppler) increased 4 fold after papaverine infusion. Left ventricular biopsies showed hypertrophy (either nuclear or cellular) in 11, myocytolysis in 6, interstitial fibrosis in 9 and lipid deposits in 4. Morphometric analysis of cardiac samples comparing the diabetic group and a control group showed that the volume fraction of fibrosis (0.19 +/- 0.06 vs 0.10 +/- 0.06; p < 0.01), fiber area -mu2- (1,062 +/- 547 vs 600 +/- 167; p < 0.02) and fiber diameter -mu- (24.2 +/- 3.3 vs 15.1 +/- 3.4; p < 0.001) were higher in the former; and volume fraction of the myocytes was higher in the latter (0.71 +/- 0.006 vs 0.89 +/- 0.07; p < 0.001). CONCLUSIONS: Left ventricular dysfunction, not related to coronary atherosclerosis or small vessel disease, is frequent in asymptomatic young diabetic patients. Abnormal pathologic findings are common in the type of cell hypertrophy, interstitial fibrosis, myocytolysis and lipid deposits.

Adolescent↗