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F Molina

Publications and source records attributed to F Molina.

At least 19 recordsLinked to original sources
PubMed2007

Targeted therapy for threatened preterm labor based on sonographic measurement of the cervical length: a randomized controlled trial.

OBJECTIVE: False positive diagnosis of preterm labor is common. As a consequence, medications including corticosteroids to promote fetal lung maturity and tocolysis are prescribed unnecessarily. We tested the hypothesis that management of threatened preterm labor based on measurement of cervical length by ultrasonography can reduce the number of women who receive inappropriate treatment. METHODS: Forty-one women with threatened preterm labor for whom a clinical decision was made to prescribe antenatal corticosteroids and tocolysis were randomized to have their cervical length measured by transvaginal ultrasound (n=21) or to receive therapy as planned (n=20). Fourteen women in the ultrasound group had a cervix longer than 15 mm and the therapy was withheld, while the other seven with a short cervix were managed in the same way as the control group. RESULTS: Three women (14%) in the ultrasound group were treated inappropriately with antenatal corticosteroids because they remained undelivered for more than a week. This compared favorably with the control group where 18 out of 20 (90%) received corticosteroids unnecessarily (relative risk (RR) 0.16; 95% confidence interval (CI), 0.05-0.39). Tocolysis was given to only seven women (33.3%) in the ultrasound group compared with 20 (100%) in the control group (RR 0.3; 95% CI, 0.15-0.54). There were no babies in either group who were born prematurely without being given a full course of antenatal corticosteroid therapy. CONCLUSION: Women with threatened preterm labor and cervical length more than 15 mm should not receive tocolysis. The issue of the safety of withholding corticosteroid therapy in this clinical scenario warrants further study.

Adrenal Cortex Hormones↗
PubMed2006

Antibodies against synthetic epitopes inhibit the enzymatic activity of mutalysin II, a metalloproteinase from bushmaster snake venom.

Mutalysin II (mut-II), a 22.5kDa zinc endopeptidase isolated from bushmaster (Lachesis muta muta) snake venom, is a direct acting fibrin(ogen)olytic proteinase. It induces monoclonal and polyclonal antibodies which efficiently neutralize the hemorrhagic effect of L. muta and several Bothrops whole venoms. To characterize epitopes of protective antibodies we have used the Spot method of multiple peptide synthesis to prepare 64 overlapping dodecapeptides frameshifted by three residues, covering the complete amino acid sequence of mut-II. The rabbit anti-mut-II antibodies binding pattern to peptides revealed several continuous antigenic regions: one in the N-terminal part, two in the central region and the other in the C-terminal of mut-II. By using homology modelling, a three-dimensional model of mut-II was built which showed that epitopes are surface exposed. Anti-peptide antibodies were raised against three peptides (one representative of each epitope region) covalently coupled as a mixture to keyhole limpet hemocyanin. Purified IgG from the resulting anti- peptide antibodies cross-reacted with mut-II and induced a dose-dependent inhibition of the mut-II catalyzed proteolysis of fibrinogen.

Animals↗
PubMed2006

A hydrogen-based variable-gain controller for anaerobic digestion processes.

An easy-to-implement controller based on gas phase measurements for anaerobic digestion processes was developed. The controller is based on the indirect control of COD in the effluent by means of controlling the hydrogen concentration in the biogas. The fast response of hydrogen under destabilizations, such as those caused by overloads, guarantees an early actuation on the system before it destabilizes. The controller is designed such that it brings the anaerobic digestion process to maximum capacity by pushing it to maximum methane production as long as hydrogen remains low. Experiments have been conducted to test the controller under organic over- and underload situations and promising performance was achieved. Further experiments must be carried out to validate the controller under a wider spectrum of situations to enable its robust industrial application.

Anaerobiosis↗
PubMed2005

Patients' responses to distraction osteogenesis: a multi-centre study.

This investigation aimed to compare and contrast practical difficulties experienced by 54 children from three different centres (Mexico City, New York, Paris) treated with either extra-oral or intra-oral distraction devices. The possible effect of distraction osteogenesis on pain/sleeping difficulty, speech and eating problems and disturbance of recreational activities and alteration in sensation were investigated. It was expected that intra-oral devices would reduce the difficulties associated with the distraction process and their psychological effect on the child. Some benefits resulting from the use of intra-oral devices were identified, these included fewer sleeping problems (P = 0.006) and less disturbance of recreational activities (P = 0.002). However, eating and maintaining oral hygiene were more problematic with intra-oral devices the differences between the intra-oral and extra-oral groups was approaching significance at P = 0.07. A major disadvantage of the extra oral device was scarring. In both groups the alteration of lip sensation was temporary, pain was limited to the time of activation of the distraction device. A high level of patients' cooperation was mandatory for successful completion of the treatment.

Adolescent↗
PubMed2005

Evidence of a decrease in nitric oxide-storage molecules following acute hypoxia and/or hypobaria, by means of chemiluminescence analysis.

Nitrate, nitrite, and other nitroso compounds (NOxs) had been proposed as possible nitric oxide (NO) storage molecules. The present work examines, by means of chemiluminescence analysis, changes in NOx serum levels in rats 1 h before and 24, 48, and 72 h after exposure to acute hypobaric hypoxia (HH; barometric pressure [P(B)] 225 mmHg, oxygen partial pressure [PO2] 48 mmHg), normobaric hypoxia (NH; P(B) 716 mmHg [Jaén city], PO2 48 mmHg), hypobaric normoxia (HN; P(B) 225 mmHg, PO2 150 mmHg), and normobaric normoxia (NN; P(B) 716 mmHg, PO2 150 mmHg) the latter as a control group. Results show a decrease in NOx levels, which reached significance 24 h after exposure in HH animals, 4 h after exposure in the HN and NH groups, and persisted after 48 h of exposure in the HN group. NOx determinations were also performed in brain (cerebral cortex, hippocampus, decorticated brain [basal ganglia-brainstem] and cerebellum), liver, kidney, lung, and heart homogenates, 72 h after the experiment, to detect persistent effects when serum NOx levels had returned to basal values. Only in cerebellum (HN group) and hippocampus (HN and NH groups) were NOx levels significantly lower than in controls. We conclude that not only acute hypobaric hypoxia but also either hypobaria or hypoxia alone induce changes in NOx serum levels. Moreover, all three episodes involve a decrease in NOxs, greater and longer-lasting in hypoxia alone than in hypobaria and hypoxia together. The exhaustion of these NO-storage molecules could be critical when, as during a hypoxic episode, the L-arginine/NOS pathway is impaired.

Adaptation, Physiological↗
PubMed2005

Basiliximab in lung transplantation: preliminary experience.

BACKGROUND: Basiliximab is a chimeric anti-interleukin-2 monoclonal antibody that has shown safety and efficacy in the prophylaxis of acute organ rejection in renal, liver, heart, and kidney-pancreas transplantation (Tx). The aim of this study was to present our initial experience with the use of Basiliximab in lung Tx. METHODS: Basiliximab (2 doses of 20 mg on day 0 and day 4) was administered to 16 patients treated with cyclosporine, azathioprine, and steroids between September 13, 2001 and August 26, 2003, including 12 men and 4 women patients with a mean age of 56.5 years (range, 19-69). The indication for use in transplantations were: reduced renal function (n = 14), post-Tx acute renal failure (n = 1) and steroid-resistant acute rejection (n = 1). Eight double-lung and eight single-lung Tx were performed for emphysema (n = 6), idiopathic pulmonary fibrosis (n = 7), silicosis (n = 2), and cystic fibrosis retransplantation (n = 1). RESULTS: The incidence of acute rejection was 16.6% (2 patients). Infections included cytomegalovirus (CMV) 33.3% (n = 4), bacterial 16.6% (n = 2), and fungal 8.3% (n = 1). Two patients died in the postoperative period and another at 3 months. There was no reaction to the medicine, and no malignancies or Bronchiolitis Obliterans Syndrome (BOS) during a follow-up period of more than 1 year in 10 patients. CONCLUSION: Basiliximab appeared to reduce the incidence of acute organ rejection and showed a good safety profile in terms of infections and adverse events.

Antibodies, Monoclonal↗
PubMed2005

Hospital outbreak caused by a carbapenem-resistant strain of Acinetobacter baumannii: patient prognosis and risk-factors for colonisation and infection.

Between October 2001 and August 2002, 30 hospital patients became infected or colonised by a multiresistant (including to carbapenems) epidemic strain of Acinetobacter baumannii (AbMR) in a hospital outbreak. This study analysed the risk-factors associated with acquisition of this epidemic strain and investigated the prognosis of patients infected by AbMR, with the aim of elucidating factors which lead to mortality. A case-control study of the acquisition of AbMR in patients infected or colonised in the hospital outbreak was performed. Independent risk-factors leading to death were studied by logistic regression analysis. Multivariate analysis of the risk-factors for colonisation/infection with AbMR revealed an independent association with the presence of an arterial catheter (OR, 1.13; 95% CI, 1.03-1.25) and administration of imipenem as monotherapy (OR, 11.12; 95% CI, 2.33-53.09). Multivariate analysis of the prognostic features leading to mortality revealed a significant association with hypotension or shock (OR, 24.63; 95% CI, 1.56-387.56) at the time of bacterial isolation.

Acinetobacter Infections↗
PubMed2005

Autoimmune rheumatic diseases in the intensive care unit: experience from a tertiary referral hospital and review of the literature.

Autoimmune rheumatic diseases (AIRD) are not uncommon in the general population and up to one third of hospitalized patients with AIRD may need admission to intensive care unit (ICU). This paper describes the causes of admission, the clinical features and outcome of 24 AIRD patients admitted to a medical ICU from a third level hospital. Thirteen patients had systemic lupus erythematosus (54.2%), three rheumatoid arthritis (12.5%), three pulmonary renal syndrome (12.5%), two dermatopolymyositis (8.3%), two scleroderma (8.3%) and one antiphospholipid syndrome (4.2%). The main causes for ICU admission were rheumatic disease flare-up (37.5%), infection (37.5%) and complications derived from rheumatic disease (29.1%). Mortality during ICU stay was 16.7% (four patients). Excluding shock requiring vasopressor support, no statistical difference was found between survivors and nonsurvivors; although there was a trend to higher test severity scores (APACHE II, ODIN) in nonsurvivors. Our results reveal a lower mortality rate in AIRD patients admitted to the ICU than reported previously. Severity scores such as APACHE II are predictors of mortality in patients with AIRD in the ICU.

Adolescent↗
PubMed2004

Molecular characterization of protective antibodies raised in mice by Tityus serrulatus scorpion venom toxins conjugated to bovine serum albumin.

The possibility of raising a humoral immune response capable of inducing in vivo protection against the lethal effects of Tityus serrulatus (Ts) scorpion venom was evaluated in the mouse model. An immunogen was prepared that consists of a toxic fraction (TstFG(50)) of the Tityus venom (this G(50) chromatography fraction represents most of the toxicity of the crude venom) conjugated to bovine serum albumin (BSA) with glutaraldehyde. TstFG(50) coupled to BSA yielded a thoroughly detoxified immunogen. BALB/c and C57BL/10 mice were immunized with this preparation and all developed an antibody response. In vivo protection assays one week after the last immunization showed that vaccinated mice could resist the challenge by twice the LD(50) of the TstFG(50), a dose which killed all control non-immune mice. The protective effect persisted nine weeks after the end of the immunization protocol. To characterize epitopes of protective antibodies we used the Spot method of multiple peptide synthesis to prepare sets of immobilized 15 mer overlapping peptides, covering the complete amino acid sequences of the main Tityus toxins, TsII and TsVII (both beta-type toxins) and TsIV, an alpha-type toxin that is the major lethal component of the venom. Antibody binding to peptides, revealed one major antigenic region in the C-terminal part of the three toxins and another region in the helical part of TsII and TsIV toxins. It is likely that these epitopes correspond to neutralizing epitopes since they correspond to regions of the toxins that are known to be involved in the active site of the toxins.

Amino Acid Sequence↗
PubMed2004

Novel mutations in the CHST6 gene causing macular corneal dystrophy.

Macular corneal dystrophy (MCD) is an autosomal recessive disease characterized by corneal opacities and caused by mutations in a carbohydrate sulfotransferase gene, known as CHST6. MCD type I patients show missense mutations in the CHST6-coding region, and MCD type II patients show a large deletion and replacement in the upstream region of CHST6. The objective of this study was to identify the genetic defect in CHST6 gene causing MCD in Italian families. We investigated MCD genotype by using polymerase chain reaction followed by direct sequencing, and results were confirmed by restriction analysis. An enzyme-linked immunosorbent assay was performed to assess the presence of sulfated keratan sulfate in the serum of MCD patients. Biochemical analysis revealed a MCD type I phenotype in two families and a type II phenotype in another family. Two novel missense mutations and a polymorphism in the coding region of CHST6 gene were identified in patients with MCD type I. In one MCD II family, a homozygous deletion in the upstream region of CHST6 gene was found.

Corneal Dystrophies, Hereditary↗
PubMed2003

One gene determines maize B chromosome accumulation by preferential fertilisation; another gene(s) determines their meiotic loss.

Genotypes of high (H(m)) and low (L(m)) male B transmission rate (B-TR) were obtained. B-TR segregation in the F2 is reported, showing that the H(m) and L(m) lines differ in a single locus we call mBt (male B transmission), controlling B preferential fertilisation in maize. The egg cells control which one of the sperm nuclei is going to fertilise them, mBt(h) egg cells being preferentially fertilised by the sperm nucleus carrying the supernumerary B chromosomes (Bs). It is hypothesised that the mBt gene is involved in the normal fertilisation of maize but the parasitic Bs take advantage of the mBt(h) allele to increase their own transmission. Selection was also carried out when the Bs were transmitted on the female side (H(f) and L(f) lines). The F1 hybrids show that the gene(s) that we call fBt (female B transmission), controlling female B-TR, is located on the A chromosomes acting at diploid level, the fBt(l) allele(s) for low transmission being dominant. This allele causes the loss of Bs at meiosis, which is shown using a specific B molecular probe to determine B presence/absence in microspores of both lines and hybrids. Maize Bs are a nice example of intragenome conflict, because the mBt and fBt loci are a polymorphic system of attack and defence between A and B chromosomes.

Biological Evolution↗
PubMed2002

The role of the external lateral parabrachial subnucleus in flavor preferences induced by predigested food administered intragastrically.

A study was undertaken of the role of the external lateral parabrachial subnucleus (PBNLe) in flavor preferences induced by the intragastric administration of predigested/cephalic food. These preferences were developed using two different learning procedures, concurrent and sequential. In the concurrent procedure, two different-flavored stimuli were presented at the same time: one stimulus was paired with the simultaneous intragastric administration of partially digested food and the other with physiological saline. In the sequential learning procedure, the two stimuli were presented at alternate sessions. The results showed that PBNLe lesions blocked acquisition of concurrent learning but had no effect on the sequential procedure. In the latter case, both lesioned and control animals showed a strong preference for the gustatory stimulus paired with partially digested food. These results are interpreted in terms of a dual neurobiological system involved in the rewarding effects of visceral signals.

Animals↗
PubMed2002

Transition from gravito- to electroconvective regimes in thin-layer electrodeposition.

The transition from gravitoconvective to electroconvective prevailing regimes in thin-layer electrochemical deposition is analyzed through variations of electrolyte viscosity at constant cell thickness. The distribution of velocity directions at the deposit front is a measure of the relative weight of electroconvection versus gravitoconvection, and a signature of that transition. The experiments are carried out under galvanostatic conditions in convection prevailing regimes. Particle image velocimetry reveals that at low viscosities, buoyancy driven convection dominates; as viscosity increases, electrically driven convection becomes more important, eventually prevailing. The transition is observed at 1.5 times the viscosity of water. The theoretical model presented reveals that an increase of the Poisson and Reynolds numbers and a decrease of the Peclet and electric Grashof numbers, when viscosity increases, makes the electroconvective motion relatively more important. The model predicts a transition at approximately two times the viscosity of water. We may conclude that, in a physicochemical hydrodynamic flow involving ions, under galvanostatic conditions, increasing viscosity damps gravitoconvection and enhances electroconvection.

Journal Article↗
PubMed2001

Partial characterization of SUVi, a new mammalian gene induced by UV-C and expressed during the S phase of the cell cycle.

By using a lacZ-based gene-trap approach, we identified a mammalian gene induced by UV-C in a Chinese hamster ovary cell clone (Menichini P et al. [1997]: Nucleic Acids Res 25:4803-4807). The activity of the encoded protein fused to a bacterial beta-galactosidase was followed through the hydrolysis of different beta-galactosidase substrates. In this study we describe how the expression of this gene is modulated during the cell cycle and in response to UV-irradiation. We show that the beta-galactosidase activity was virtually undetectable in quiescent cells (G[0]), started to increase when cells progressed in G(1), and reached a maximum in mid-S phase, indicating a possible role of the endogenous protein during DNA synthesis. Following UV-irradiation, besides a delay of the progression through the S phase, a twofold increase of the reporter protein activity in all phases of the cell cycle was observed. The partial sequence analysis showed that this gene, here named SUVi (for S phase UV-inducible), contains a domain that is highly conserved among different helicases. Together, these data suggest that the SUVi gene could be involved in DNA synthesis, a process that takes place both in the S phase and in the processing of UV-induced damage.

Animals↗
PubMed2001

Antibodies against a putative heparin receptor slow cell proliferation and decrease MAPK activation in vascular smooth muscle cells.

Heparin has long been known to slow the growth of vascular smooth muscle cells. However, the mechanism(s) by which heparin acts has yet to be resolved. The identification of a putative heparin receptor in endothelial cells with antibodies that blocked heparin binding to the cells provided the means to further examine the possible involvement of a heparin receptor in smooth muscle cell responses to heparin. Immunoprecipitation of a smooth muscle cell protein with the anti-heparin receptor antibodies provided evidence that the protein was present in smooth muscle cells. Experiments with the anti-heparin receptor antibodies indicate that the antibodies can mimic heparin in decreasing PDGF induced thymidine and BrdU incorporation. The anti-heparin receptor antibodies were also found to decrease MAPK activity levels after activation similarly to heparin. These results support the identification of a heparin receptor and its role in heparin effects on vascular smooth muscle cell growth.

Animals↗
PubMed2001

Effects of a flavor-placement reversal test after different modalities of taste aversion learning.

Taste aversion learning is induced through two different behavioral procedures: a short-term or concurrent (two-daily flavors) and a long-term or sequential (one-daily flavor) procedure. For the concurrent group of animals, two gustatory/olfactory stimuli are presented separately but at the same time on a daily basis. One is paired with simultaneous intragastric administration of hypertonic NaCl and the other with physiological saline. For the sequential group, the two stimuli are presented on alternate days, one of them followed by intragastric injection of the aversive stimulus and the other by saline, both after a delay of 15 min. The two groups learned the task, but when they were subjected to a flavor-placement reversal test only the sequential group was successful in achieving it. In a second experiment, three groups of animals had to learn concurrent or sequential discrimination tasks (with either simultaneous or delayed administration of the visceral stimulus) using only spatial/proprioceptive cues. The data show that none of the groups learned them under these conditions. The results are discussed in terms of the different modalities of learning. Short-term and long-term taste aversion learning are different in the anatomical structures involved, the number of trials required for acquisition and, as shown in this paper, flexibility.

Animals↗
PubMed2001

[Mandibular elongation and remodeling by gradual distraction. An experience of 277 cases].

Distraction osteogenesis at the craniofacial skeleton offers superior results than using standard osteotomies and other surgical techniques when treating mandibular hypoplasia. After ten years, we have performed 221 patients with hemifacial microsomia and 56 patients with micrognathia using external mandibular distraction. For every single patient the distraction vector is different according to the degree of bone hypoplasia. The bone elongation ranged from 12 to 49 mm, and the results were excellent: facial symmetry was reestablished, the menton became horizontal and the long term result controls shows stability clinically and occlusally.

Adolescent↗