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F Alvarez

Publications and source records attributed to F Alvarez.

At least 55 records · Page 3Linked to original sources
PubMed2000

Citrate utilization by homo- and heterofermentative lactobacilli.

Citrate utilization by several homo- and heterofermentative lactobacilli was determined in Kempler and McKay and in calcium citrate media. The last medium with glucose permitted best to distinguish citrate-fermenting lactobacilli. Lactobacillus rhamnosus ATCC 11443, Lactobacillus zeae ATCC 15820 and Lactobacillus plantarum ATCC 8014 used citrate as sole energy source, whereas in the other strains, glucose and citrate were cometabolized. Some lactobacilli strains produced aroma compounds from citrate. Citrate transport experiments suggested that all strains studied presented a citrate transport system inducible by citrate. The levels of induction were variable between several strains. Dot blot experiment showed that lactobacilli do not present an equivalent plasmid coding for citrate permease.

Acetoin↗
PubMed2000

Autoantibodies in recent onset type-1 diabetic patients to a Mr 60K microsomal hepatic protein: new evidence for autoantibodies to the type-2 glucose transporter.

Here we describe the presence of IgG antibodies, in the sera of patients presenting with insulin-dependent diabetes mellitus (IDDM), that react in Western blots with a 60-kD protein (Mr 60K) from rat hepatic microsomal extracts. Sera from 60 IDDM patients were screened and 31.6% were positive for the Mr 60K band. This antibody reactivity was indistinguishable in terms of both molecular weight and isoelectric point (pI 5.4) from that described in some patients presenting with autoimmune hepatitis who may also develop IDDM. We hypothesized that the type-2 glucose transporter (Glut-2) that is expressed on both hepatocytes and pancreatic beta cells could be a putative target for the detected antibodies. A polyclonal antisera to rat Glut-2 used in the liver microsome Western blot identified a 60-kD band superimposable upon that evidenced by IDDM sera. Antisera to Glut-2 successfully inhibited the binding of the patient's IgGs to liver microsomes, further suggesting that the two proteins may be identical. Using protein extracts from a rat insulinoma cell line (RIN) transfected with the human Glut-2 cDNA, further evidence was obtained suggesting that these IDDM IgGs are specific for the human Glut-2 transporter.

Animals↗
PubMed2000

Statistical models for predicting response to interferon-alpha and spontaneous seroconversion in children with chronic hepatitis B.

To develop prognostic models for identifying children with hepatitis B who are likely to respond to interferon-alpha (IFN-alpha) or to spontaneously seroconvert, we evaluated results of a multinational controlled trial comprising 70 children with chronic hepatitis B who received IFN-alpha and 74 children who did not receive therapy. Prognostic models were developed using SMILES (similarity of least squares), which is a data analysis network that incorporates multidimensional relationships in the clinical data of complex diseases. Commonly collected clinical data included age, gender, serum aminotransferase (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) and hepatitis B virus (HBV) DNA levels, and IFN-alpha dose. Additional data included pretreatment directional information (e.g. increases or decreases in serum aminotransferase and HBV DNA levels), liver biopsy results, race and transmission mode. Using data available prior to initiation of treatment, the SMILES models achieved prospective predictions of 89% for responders, 96% for non-responders, 100% for seroconverters and 93% for non-seroconverters. Although not predictive by themselves, the variables that had the greatest impact on predictions for IFN-alpha response were HBV DNA pretreatment direction, baseline HBV DNA, IFN-alpha dose and gender. The variables that had the greatest impact on predictions for spontaneous seroconversion were ALT pretreatment direction, baseline HBV DNA level, age and AST pretreatment direction. Therefore, these models may be useful in determining, in children with hepatitis B, the likelihood of response to IFN-alpha and spontaneous seroconversion.

Adolescent↗
PubMed2000

Extra-laryngeal head and neck tuberculosis.

OBJECTIVE: Extra-laryngeal head and neck tuberculosis is exceptional. Therefore, a retrospective multicenter study in patients with head and neck tuberculosis, excluding solitary lymphadenitis and laryngeal locations was carried out. METHODS: We reviewed the patients with these features and tuberculosis confirmation by culture and/or histologic granuloma with presence of acid-fast bacilli (AFB). RESULTS: We found 16 patients with the following locations: eight in oral cavity and/or pharynx, four in ear, two in salivary glands, one in nose and one in frontal sinuses. The average duration of symptoms was 11.5 months. Purified protein derivative (PPD) was positive (> 10 mm) in all but one patient in whom it was performed (six of seven). Except tuberculous otitis, which occured without reactive lymphadenitis, this was present in 50% of the rest (six of the 12). In all cases a biopsy was required for diagnosis. Only in four patients, all with pharyngeal locations, was coincident pulmonary tuberculosis confirmed. One patient with tuberculous otitis developed meningitis and died; three additional patients (two with otitis) were cured but with sequelae; the evolution of the remaining patients was satisfactory with medical therapy. CONCLUSIONS: Extra-laryngeal head and neck tuberculosis has a slow course. The diagnosis is difficult due to the common absence of lung involvement and the usual requirements for biopsy procedures. The outcome is usually favorable with antituberculous drugs alone although in tuberculous otitis there are possibilities of complications.

Adolescent↗
PubMed2000

Past and future of biliary atresia.

BACKGROUND: With the advent of liver transplantation the outcome of children with biliary atresia (BA) has improved. Is Kasai hepatic portoenterostomy (KHPE) still a valuable option for the treatment of these patients? METHODS: From 1974 to 1998, 77 patients with biliary atresia have been treated at our institution: 50 girls and 27 boys. RESULTS: Seventy-four patients had a KHPE, and 3 patients had no KHPE because of delay in diagnosis. A total of 65 of 74 patients (88%) had undergone KHPE type I, 4 patients (5.4%) KHPE type II, 3 patients (4%) had a Suruga modification, and 2 patients (2.6%) had a portocholecystostomy. Among the 74 patients, 11 were lost to follow-up and their cases were considered failures. Seventeen of our patients are alive at long-term follow-up after KHPE. Among the 77 patients, 33 (43%) had an orthotopic liver transplantation (OLT). Successful KHPE patients underwent transplant at a mean age of 9 years, and KHPE failed at a mean age of 11 months. A total of 25 of 77 (32%) of patients are alive thanks to OLT. In the cohort, the overall survival rate for the KHPE plus OLT is 42 of 77 (55%). Mortality and morbidity rates were more frequent among the younger patients who had early OLT after KHPE failure. In our series, overall survival rate was improved when the patient had a successful KHPE (P < .001). CONCLUSIONS: Kasai hepatic portoenterostomy (KHPE) continues to be a valuable procedure in the treatment of infants with biliary atresia (BA). Successful KHPE permits transplantation at an age at which mortality and morbidity are decreased leading to a better outcome.

Biliary Atresia↗
PubMed2000

Primary costochondritis due to Escherichia coli.

We present a case of primary costochondritis by Escherichia coli, in a diabetic woman. The patient suffered a urinary infection by E. coli which may have been the source of haematogenous spread. She received medical and surgical therapy and 5 months later, she was asymptomatic.

Aged↗
PubMed2000

Periosteal glomus tumor of the femur: a case report.

Osseous abnormalities produced by glomus tumors located in soft tissues of the periungual region have been described. More rare is the location of a glomus tumor within bone, which usually is located in the phalanx of the fingers. However, to the authors' knowledge, there is no previous description of a glomus tumor located in a periosteal location of a long bone. A 50-year-old man with a glomus tumor in a periosteal location of the lower metaphysis of the femur without neoplastic erosion of the cortical surface is reported. Magnetic resonance imaging and intraoperative ultrasonography were needed to locate the lesion.

Femoral Neoplasms↗
PubMed2000

Preliminary safety and acceptability of a carrageenan gel for possible use as a vaginal microbicide.

OBJECTIVE: We sought to determine the safety and acceptability of vaginal gel formulation PC-503 among low risk, abstinent women. The active ingredient was 2% pharmaceutical grade lambda carrageenan, a sulphated polymer that is generally recognised as safe by the US Food and Drug Administration. METHODS: 35 women in five sites applied 5 ml of the PC-503 gel vaginally once a day for 7 days while abstaining from sexual intercourse. Visual vaginal examinations were performed on days 1, 4, and 8. STI testing and vaginal pool Gram stain preparations were done on days 1 and 8. Participants were asked about product acceptability. RESULTS: 34 of the 35 women enrolled completed 7 days' use. Following product use, five reported mild symptoms including "bladder fullness," "genital warmth," or discomfort, and lower abdominal pain, and one had moderate pale yellow cervical discharge. Using the Nugent criteria, three women had bacterial vaginosis (BV) before and after use; three had BV before but not after, and two had BV after but not before. Most of the women found PC-503 to be pleasant or neutral in feel and smell and considered extra lubrication to be an advantage; however, one third found it to be messy. CONCLUSIONS: Vaginal use of PC-503 gel did not cause significant adverse effects in a small number of low risk, sexually abstinent women. Further testing in larger numbers of sexually active women is planned. A smaller volume of gel may be more acceptable to some women.

Anti-Infective Agents, Local↗
PubMed2000

Pulmonary alveolar proteinosis in association with household exposure to fibrous insulation material.

We report the case of a 35-year-old woman who developed pulmonary alveolar proteinosis requiring multiple lavage treatments, in association with household exposure to ventilation system dust comprised at least partially by a cellulose fire-resistant fibrous insulation material. Scanning electron microscopy with energy-dispersive x-ray analysis documented the presence of spectral peaks consistent with the insulation material in transbronchial biopsy tissue. The patient showed symptomatic improvement once exposure to the insulation material had ceased. We believe that this case demonstrates an unusual association with pulmonary alveolar proteinosis. This case emphasizes the broad differential diagnosis for this histologic injury pattern and the need to thoroughly investigate environmental exposures in patients with unexplained pulmonary disease.

Adult↗
PubMed1999

Viral-antigen dependence and T-cell receptor expression in leucocytes from rhabdovirus immunized trout.

This work describes the characterization of trout haematopoietic in vitro long-term cell cultures showing specific viral antigen-dependent cell (ADC) proliferation. The ADC cultures were developed from outbreed trout after surviving viral hemorrhagic septicaemia virus (VHSV) infections or after immunization with purified VHSV. For in vitro long-term proliferation of the ADC cultures, adherent (Ad) cells obtained from autologous trout were pulsed with VHSV recombinant glycoprotein G4 (G4-pulsed Ad cells) and added periodically to the cultures. ADC did not proliferate in cultures obtained from non-infected control trout treated in parallel with G4 or from VHSV survivor/VHSV immunized trout kidney donors treated with non-viral proteins. After months in culture, the ADC acquired an increasingly homogeneous morphology compatible with that of mature trout lymphocytes, secreted supernatant 'factors', and were stained with rabbit antibodies to the ectodomain of recombinant trout T-cell receptor (TcR) beta-chain. Together with all the above mentioned properties, the presence of TcR sequences in the ADC cultures confirmed by the expression of alpha- and beta-chain TcR by nested PCR amplification and sequencing of the amplified bands, suggests that these ADC cultures contain trout T-like cells engaged in a VHSV response. These trout ADC cultures offer a first opportunity to further analyze fish anti-viral immunological responses.

Animals↗
PubMed1999

Timing of onset of contraceptive effectiveness in Norplant implant users. II. Effect on the ovarian function in the first cycle of use.

The objective of this study was to time the onset of contraceptive effectiveness in Norplant implant users, when the capsules were inserted beyond the first 7 days of the cycle, based on the immediate effect on the ovarian activity. A total of 42 healthy women requesting Norplant implant contraception were enrolled at clinics in Santo Domingo, Dominican Republic, and in Baltimore, Maryland. Implants were inserted on days 8-13 of the menstrual cycle. Blood samples for estradiol (E2), progesterone (P), luteinizing hormone (LH) (in a subset of 12 women), and levonogestrel (LNG) assay, were taken at 0 h and at 6, 12, 24, 72, and 168 h postinsertion. Ovulation, as defined by P > 2.5 ng/mL, occurred in 40% of subjects. A short lasting, frequently blunted, LH peak occurred within 12 h postinsertion, in all these subjects. The remaining subjects had anovulatory cycles with two distinct E2 profiles: continuously increasing E2 levels to a high mean of 414.3 pg/mL (28%), or no sustained increase in E2 (32%). Most cycles (86%) in which Norplant was inserted with high E2 levels (> 175 pg/mL) were ovulatory, whereas none were ovulatory with low E2 (< 100 pg/mL) at insertion. Based on the endocrine effects of Norplant implant insertion in the midadvanced follicular phase, in which ovulation will either occur within 48 h of insertion or will be impaired, additional contraceptive protection is necessary only for 3 days.

Adolescent↗
PubMed1999

Efficacy, bleeding patterns, and side effects of a 1-year contraceptive vaginal ring.

A combined contraceptive vaginal ring designed to last 12 months was tested at three clinic sites. This ring released approximately 1 mg of norethindrone acetate (NET-Ac) and 20 micrograms of ethinyl estradiol (EE) daily. A total of 60 women were enrolled to use the ring in a schedule of 3 weeks in/1 week out. Serum norethindrone (NET) and ethinyl estradiol (EE) levels were assayed twice weekly in cycles 6, 9, and 13. Mean NET concentrations between cycles 6 and 9 were relatively stable between 13 and 19 nmol/L but showed a 10%-21% decrease in all centers between cycles 9 and 13. Mean EE concentrations ranged from 75 to 103 pmol/L, but did not have the same decrease as NET between cycles 9 and 13. Cycles with progesterone peaks (> 9.6 nmol/L) compatible with some luteal activity occurred in 4% of cycles sampled in Sydney, 3% in Santo Domingo, and 26% in Los Angeles. Half of these cycles exhibited at least one progesterone value > 32 nmol/L with three of 18 occurring in noncompliant cycles. Heavier body weight was associated with increased probability of luteal activity. Based on serum estradiol peaks > 400 pmol/L, eight of 81 cycles appeared to have marked follicular activity with no luteal activity. No pregnancies occurred. Nausea was reported by about half the subjects in approximately 10% of the visits (mainly in the first 1-2 days in the first cycle immediately after ring insertion). Vomiting was reported by 20% of subjects early in the first cycle only. Headache was reported on occasion by nearly 50% of the women, but the relationship to ring use was uncertain. Vaginal discharge was reported by 17 women (82% of these were from one clinic). Of 60 women, 14 discontinued before completing the study, but only two discontinuations were for medical reasons. Small but statistically significant changes occurred in lipid levels in two of the three centers. All changes remained within normal limits and were similar to those seen with many oral contraceptives. It appears that this ring may perform slightly differently in different populations, but is a highly satisfactory method of contraception for many women. Minor modifications in design could provide higher levels of steroid release and in the later months of the ring life span would assure continuing high levels of contraceptive protection for heavier women.

Adolescent↗
PubMed1999

Formiminotransferase cyclodeaminase is an organ-specific autoantigen recognized by sera of patients with autoimmune hepatitis.

BACKGROUND & AIMS: Anti-liver cytosol type 1 autoantibodies have been reported in association with anti-liver-kidney microsome type 1 autoantibodies in 30% of patients with autoimmune hepatitis type II. In 10% of cases, anti-liver cytosol type 1 antibodies are the only liver-related circulating autoantibodies. The liver cytosol antigen is a liver-specific 62-kilodalton protein present in the cell as an oligomer of approximately 240 kilodaltons. The aim of this study was to identify the antigen recognized by anti-liver cytosol antibody. METHODS: To identify the liver cytosol antigen, an anti-liver cytosol type 1-positive serum was used for the screening of a complementary DNA library from HepG2 cells. Double immunodiffusion method was used to show the identity between the cytosolic and the cloned protein. RESULTS: The sequence of two isolated clones showed 85.2% homology with the formiminotransferase cyclodeaminase (FTCD) enzyme from pig liver. Antibodies purified by affinity with the recombinant protein and sera from mice immunized with FTCD recognized a 62-kilodalton human cytosolic protein when tested by immunoblot. The identity of precipitation lines was found between the cytosolic antigen and FTCD. CONCLUSIONS: This enzyme is a liver-specific antigen recognized by the sera of patients with autoimmune hepatitis.

Amino Acid Sequence↗
PubMed1999

Short-term cyclosporine induces a remission of autoimmune hepatitis in children.

BACKGROUND/AIMS: The current immunosuppressive treatment of patients with autoimmune hepatitis consists of prednisone and azathioprine. High doses of prednisone used to obtain the remission of the disease are associated with serious adverse effects. To avoid harmful consequences of prednisone therapy, we proposed to treat patients with oral cyclosporine to obtain the remission of the inflammatory process. METHODS: This is a pilot, multinational, multicenter, clinical trial involving children with autoimmune hepatitis. Thirty-two children were recruited, who according to international criteria were considered as having definite autoimmune hepatitis. Cyclosporine alone was administered for 6 months, followed by combined low doses of prednisone and azathioprine for 1 month, after which cyclosporine was discontinued. Biochemical remission of the disease was established by the follow-up of serum transaminase activity levels. Growth parameters and adverse effects of the treatment were recorded. RESULTS: Two patients were withdrawn from the study: one for non-compliance and the other for liver failure which did not improve with cyclosporine. Of the 30 remaining patients, 25 normalized alanine aminotransferase activity levels by 6 months and all the patients by 1 year of treatment. Z-scores for height showed a trend towards improvement during treatment. Adverse effects of cyclosporine were mild and disappeared during weaning off the medication. CONCLUSIONS: Cyclosporine induced the biochemical remission of the hepatic inflammatory/necrotic process in children with autoimmune hepatitis, with few and well-tolerated adverse effects.

Adolescent↗
PubMed1999

Correlation of endocrine profiles with bleeding patterns during use of Nestorone contraceptive implants.

The relationship between ovarian hormones and bleeding patterns during continuous progestin contraception was studied in 29 women who used Nestorone (NES) releasing implants. Oestradiol and progesterone were measured in blood samples taken twice a week for 6 consecutive weeks, during months 6, 12, 18 and 24 of implant use. Retrospectively, the association between hormonal concentrations and bleeding patterns was evaluated. Twenty-four short (</= 24 days), 36 normal (25-35 days), 27 long (36-90 days) and nine episodes of amenorrhoea, as well as 28 periods of prolonged bleeding, were identified. Short cycles, periods of prolonged bleeding and amenorrhoea were characterized by low oestradiol concentrations. Bleeding after a normal or long cycle regularly occurred after a rise and fall of oestradiol or oestradiol and progesterone. The duration of bleeding was directly and significantly associated with the highest concentration of oestradiol in the previous 15 days in anovulatory cycles. Luteal activity was associated with shorter duration of bleeding. Periods of prolonged bleeding were usually initiated with a drop in oestradiol and over half ended with an increase in oestradiol. It was concluded that changes in endogenous hormone have a significant influence over the bleeding pattern during use of NES implants.

Adolescent↗
PubMed1999

Variations in vaginal epithelial surface appearance determined by colposcopic inspection in healthy, sexually active women.

A total of 107 sexually active women, aged 18-35 years, was recruited through family planning clinics in four centres in different countries. Each woman underwent two or three gentle but thorough and systematic vaginal inspections using a consistent technique with colposcopic magnification over a 4-6 month period to look for changes in vaginal and cervical appearance which might be related to sexual intercourse, tampon use, contraceptive method used, cigarette smoking or other environmental factors. Obvious changes in appearance were photographed at x10 magnification. These 'appearances' or 'conditions' were classified according to a modification of the recommendations of a workshop sponsored by the World Health Organization, the Population Council and the Conrad Program. Most of these alterations in the appearance of the vaginal epithelium were judged to be of such minor clinical importance that they have been termed 'conditions' or 'changes in appearance' rather than 'lesions'. In all, 56 'conditions' or 'appearances' were noted in 314 inspections, the commonest being petechiae (53.6%). Potentially significant conditions justifying the term 'lesions' (three microulcerations, two ecchymoses, five abrasions and one mucosal tear; 3.5% of inspections) usually healed spontaneously and disappeared rapidly. The incidence of these conditions was highest when the inspections followed intercourse in the previous 24 h (25.2 versus 14.2%; P < 0.0008), or tampon use (32.4 versus 15.9%; P < 0. 0001). These processes may be regarded as a reflection of regular minor trauma to the vaginal epithelium.

Adolescent↗
PubMed1999

Accuracy of the [13C]-urea breath test in diagnosing Helicobacter pylori gastritis in pediatric patients.

BACKGROUND: The causal association between Helicobacter pylori (H. pylori) colonization of the gastric mucosa and gastritis is now well established. Histologic examination of endoscopic biopsy specimens has long been regarded as the gold standard for diagnosis. However, the changes can be focal in nature and presence of the organism may be missed in nonsampled areas. The urea breath test, which uses a stable isotope, offers distinct advantages, in that it is noninvasive and measures the activity of the micro-organism. It thus represents a potentially invaluable tool in the initial diagnosis of the infection and in verifying its eradication. METHODS: The study design was that of a prospective, blinded comparison of the [13C]-urea breath test with histologic assessment of antral biopsy specimens using the Warthin-Starry stain, to diagnose H. pylori infection in a group of 79 consecutive pediatric patients. RESULTS: Patients classified as negative by histology (n=67) had breath 13C enrichment of 0.97+/-0.07 delta per thousand (mean+/-SEM), with a range of -0.20 and 2.83 delta per thousand. In contrast, those with a positive histologic results (n=12) had an enrichment of 25.41+/-5.01 delta per thousand (range, 3.43-58.80; p < 0.001). At the chosen cutoff point of 3 delta per thousand, the sensitivity and specificity as well as the positive and negative predictive values of the breath test were uniformly 100%. CONCLUSION: The [13C]-urea breath test is a highly reliable, noninvasive method for the diagnosis of H. pylori gastritis in children and adolescents.

Adolescent↗