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M Herrera

Publications and source records attributed to M Herrera.

At least 55 records · Page 3Linked to original sources
PubMed1999

[Life-threatening hemoptysis. Treatment with transcatheter embolization].

OBJECTIVE: To evaluate the immediate and long-term efficacy of transcatheter embolization of bronchial, systemic and pulmonary arteries to treat life-threatening hemoptysis. Likewise, we propose the systematic treatment of life-threatening hemoptysis by means of transcatheter embolization. MATERIAL AND METHODS: One hundred seven angiographies were performed on the same number of patients experiencing life-threatening hemoptysis with bleeding exceeding 150 ml in 24 hours. Before angiography, we rinsed the vessels with cold saline solution and adrenalin through the catheter. Thirty-three patients were female and 74 were male. Mean age was 52.3 years (range 12 to 75 years). Embolization was performed in 104 (3 in patients with recurrent hemoptysis) using polyvinyl alcohol and micro-coils. Bronchial and systemic arteries of the affected hemithorax (mammary and lateral thoracic arteries) were checked in all patients. If findings were negative or bleeding was recurrent, we also performed pulmonary arteriography. RESULTS: In two cases we were unable to catheterize the artery theoretically responsible for bleeding. Examination of both arterial and systemic vessels proved normal in one patient. The embolization technique was successful in 99% (103/104) of the cases and the rate of immediate clinical success was 95.1% (99/104). The mean time of follow-up was 43.2 months (range 3 to 66 months). Hemoptysis recurred in 15.3% (16 cases) within a mean 8.3 months (range 15 days to 48 months); embolization was repeated in 14 of these patients with satisfactory results, while two underwent surgery. In five patients (4.8%) we observed complications requiring no additional medical treatment: one instance of coil migration to the deep femoral artery, from which the coil was removed in a basket; two cases of bronchial artery extravasation with small mediastinal hematomas; and two hematomas at the points of puncture. CONCLUSION: Selective or supra-selective embolization of the arteries that feed the bronchi provides effective management of life-threatening hemoptysis. No additional medical treatment is usually required.

Adolescent↗
PubMed1998

Deletion patterns in Argentine patients with Duchenne and Becker muscular dystrophy.

The identification of mutations in Duchenne or Becker muscular dystrophy (DMD/BMD) patients is important for carrier detection in these families. We present the patterns of deletions of the dystrophin gene in Argentine population. DNA from 75 patients with DMD/BMD was analyzed by multiplex PCR and, in some cases, cDNA/Southern. Deletions were detected in 24 patients (32%) and were mainly clustered in two areas of the dystrophin gene: the 5' end (exons 3-12) and the central part (exons 44-53). 64% of the deletion endpoints lay in the middle region and 34% in the 5' end of the gene. The most frequent sites for deletion-endpoints were in the introns 47 (13.6%), 44 (11%), 2 (9%) and 12 (7%). Thus, the proportion and distribution of deletions in our DMD/BMD patients differ from those reported for other populations. Furthermore, a higher proportion of deletions was observed in familial cases (40%) than in isolated ones (30%), in contrast to previously reported data. The effect of the deletion on the reading frame agree with the phenotype in almost all the patients studied. This study will be useful in prenatal diagnosis and diagnosis of other Argentine DMD patients.

Adolescent↗
PubMed1998

Microbiology of acute otitis media in Costa Rican children.

BACKGROUND: Because of the increasing number of resistant middle ear pathogens reported from different centers worldwide, an active surveillance of the microbiology and susceptibility pattern of middle ear pathogens is required for proper antimicrobial recommendations among different regions of the world. OBJECTIVE: To study the microbiology and susceptibility pattern of middle ear pathogens obtained from Costa Rican children with acute otitis media. METHODS: Between 1992 and 1997 a diagnostic tympanocentesis was performed in 398 Costa Rican patients with acute otitis media. Middle ear fluid was obtained for culture and minimal inhibitory concentrations were determined by the E-test technique in those isolates obtained between October, 1995, and January, 1997. RESULTS: The most common pathogens cultured were Streptococcus pneumoniae (30%), Haemophilus influenzae (14%), Staphylococcus aureus (4%) and Streptococcus pyogenes (4%). Moraxella catarrhalis was uncommon. Beta-lactamase production was low (3.7%) among the H. influenzae isolates but frequent among the Staphylococcus aureus (57.1%) and M. catarrhalis (100%) strains. Overall 9 of 46 S. pneumoniae isolates (19.6%) exhibited decreased susceptibility to penicillin of which 8 isolates (17.4%) showed intermediate and one strain (2.2%) high level resistance. Among the penicillin-susceptible S. pneumoniae isolates, susceptibility to the following antimicrobials was: 81%, azithromycin; 89%, clarithromycin; and 100%, ceftriaxone and trimethoprim-sulfamethoxazole (TMP-SMX). Among the penicillin-resistant S. pneumoniae isolates the percentage of susceptible strains was 89% for azithromycin, clarithromycin and ceftriaxone and 67% for TMP-SMX. CONCLUSIONS: Based on this microbiologic information the agents considered first line drugs in the treatment of acute otitis media in Costa Rica remain amoxicillin or TMP-SMX.

Acute Disease↗
PubMed1998

Acute colorectal obstruction: stent placement for palliative treatment--results of a multicenter study.

PURPOSE: To evaluate the usefulness of stent implantation as a palliative treatment in patients with acute colonic obstruction who are not surgical candidates. MATERIALS AND METHODS: Twenty-four patients (eight women, 16 men; age range, 60-98 years) with acute colonic obstruction underwent colonic stent placement. In nine patients, the procedure was considered a primary palliative treatment; seven patients had a previous diagnosis of disseminated neoplastic disease, and two were not surgical candidates because of their poor general condition. In the remaining 15 patients, stent placement was considered the definitive palliative treatment after tumor staging. The mean time of follow-up was 8.4 months (range, 1-24 months) for patients who lived and 6.3 months (range, 1-12 months) for those who died. RESULTS: Stent placement was successful in all patients. Clinical and radiographic findings of bowel obstruction resolved within 24 hours after stent placement in 23 (96%) patients. None of the patients required colostomy for bowel decompression after immediate stent placement. Complications developed in 10 (42%) patients: Two (8%) patients had mild rectal bleeding; three (12%), abdominal pain; two (8%), malpositioning of the stent; two (8%), pseudo-obstructive episodes due to fecal impaction; and one (4%), occlusive tumor ingrowth into the stent lumen. One (4%) patient underwent surgery to resolve stent malfunction due to poor positioning. Two (8.3%) patients--one with malpositioning of the prosthesis and the other with stent occlusion--required a new stent. The remaining complications required no further treatment. The mortality rate at 6 months was 24%. Eight patients were alive at the time this article was written. CONCLUSION: Colorectal stent placement resulted in successful palliation of acute colonic obstruction in patients with disseminated neoplastic disease.

Acute Disease↗
PubMed1998

bcl-2 expression in plasma cells from neoplastic gammopathies and reactive plasmacytosis: a comparative study.

BACKGROUND AND OBJECTIVE: bcl-2 oncoprotein plays a major physiological role in hemopoietic and non-hemopoietic cells by preventing apoptosis (programmed cell death). Disregulation of this process may be important in oncogenesis and the response to treatment of patients with different hematological malignancies. We have investigated the levels of bcl-2 expression in plasma cells from patients with reactive plasmacytosis (RP), monoclonal gammopathy of unknown significance (MGUS) and multiple myeloma (MM), correlating the bcl-2 expression and clinico-biological features in MM patients. DESIGN AND METHODS: The percentage of bcl-2 (+) plasma cells and levels of bcl-2 protein expression were investigated in 73 patients at diagnosis. Immunofluorescence and immunoenzymatic methods were applied using McAb against bcl-2 protein, and the intensity of protein expression was assessed by both the mean channel fluorescence intensity (MFI) and semiquantitative methods. To evaluate the intensity of bcl-2 expression in proliferating plasma cells, sequential double immunoenzymatic staining with McAb Ki-67 and bcl-2 was applied in 10 patients with MM. Correlations between bcl-2 expression and the clinico-biological features in MM patients were also studied. RESULTS: The proportion of bcl-2 (+) plasma cells was significantly higher in MGUS and MM than in RP (p < 0.001). The intensity of bcl-2 expression in plasma cells (assessed by MFI) was significantly different between all groups studied (p < 0.0001). RP showed lower expression than MGUS and MM patients. MM stage III patients demonstrated higher bcl-2 expression values than MGUS (p < 0.01). According to the proportion of plasma cells expressing Ki-67, patients with a proliferative index (Ki-67+) > 4% showed lower bcl-2 expression than patients with proliferative index < 4% (p < 0.05). Immunocytochemistry showed that plasma cells from RP had a lower intensity of bcl-2 expression than MM (p < 0.001), and double immunostaining Ki-67/bcl-2 demonstrated that the majority of proliferating plasma cells had weak bcl-2 expression. There was no correlation between bcl-2 expression and clinico-biological parameters, response to therapy or overall survival in MM patients. INTERPRETATION AND CONCLUSIONS: Globally, the number of bcl-2 (+) plasma cells and the intensity of protein expression in neoplastic gammopathies are significantly higher than in reactive plasmacytosis and bcl-2 levels tend to increase with disease stage. bcl-2 may be relevant to the pathogenesis of malignant gammopathies, prolonging the survival of plasma cells by preventing apoptosis and increasing the chance of acquiring additional gene defects. bcl-2 expression could also contribute to the resistance to chemotherapy observed in MM disease.

Adult↗
PubMed1998

[Spinal anesthesia. Repercussions on childbirth].

A study was carried out to discover the action of epidural anesthesia on pain, on the evolution of dilation and expulsion intervals, on the number of surgically assisted births, and on perinatal morbidity. Some of the most significant results indicated that with good techniques, pain disappears in all cases; that the dilating period is significantly shortened with epidural anesthesia, although there is an increase in instrumental-assisted childbirths. Even though epidural anesthesia is, as of this writing, the best method available, the ideal pain reduction method has yet to be discovered. Part of this study was presented before the National Congress of Midwives and received the "Nuk" Prize.

Anesthesia, Epidural↗
PubMed1998

Prenatal diagnosis of intra-atrial cardiac echogenic foci.

Intra-atrial echogenic foci were detected in 3 out of 15,706 fetuses (prevalence 0.019 per cent). In all cases, they were located in the right atrium. Normal chromosomes and negative TORCH titres were observed in all affected cases. Fetuses with intra-atrial echogenic foci demonstrated adequate intra-uterine growth and had normal neonatal outcome. Intra-atrial echogenic foci seem to represent a normal variant of fetal cardiac development.

Echocardiography↗
PubMed1998

[Caudal regression syndrome].

INTRODUCTION: The regression caudal syndrome includes a spectrum of malformations which vary from the symptomless coccygeal agenesis until thoracic vertebrae and sacrococcygeal agenesis with severe neurological deficit; it is associated sometimes with malformations in other organs and systems. We present a case of partial agenesis of sacro and coccix with neuromuscular, sphincter and orthopedist alterations. CLINICAL CASE: A 4-year-old patient consults because of walk alterations, with daytime and nocturnal enuresis and urinary incontinence, constipation/encopresis and rectal prolapse. Familiar and personnel precedents are uninteresting. She began to walk at normal age, referring only rectal prolapse with constipation from nursing and urinary tract infections and encopresis when she was 3 years old, with normal complementary explorations (digestive and nephrourologyc). She presents in lumbosacral X-rays four lumbar vertebrae, a dysplasic sacro and absence of coccix. Hypoplasy of sacro with bilateral stenosis of the pelvis and coxa vara in both femurs are seen in the lumbar CT. In RMI is observed agenesis of sacro and coccix vertebrae. CONCLUSIONS: There are a wide variety of sacrococcygeal agenesis, which are classified by Renshaw and modified by Pang. As etiologics factors we find the gestational diabetes, in addition to genetic factors. The clinic exploration guides us toward a flaccid paraparesia/areflexia, with orthopaedist alterations, sometimes of artrogripotyc type. With image techniques (X-rays, CT, MRI) we can accomplish the diagnosis and we can discard or demonstrate associated medullary anomalies. We concluded that in all patient with alterations of walk and/or lack of sphincters control we should explore the lumbosacral region searching for medulodiysplasic or vertebral alterations.

Abnormalities, Multiple↗
PubMed1997

Effects of nebulized salbutamol on respiratory mechanics in adult respiratory distress syndrome.

OBJECTIVE: To determine whether nebulized salbutamol improves the respiratory mechanics of patients with adult respiratory distress syndrome (ARDS). We also assessed the mechanisms that contribute to high respiratory system resistances during this disease. PATIENTS AND SETTING: Eleven consecutive patients with ARDS without clinical evidence of chronic obstructive pulmonary disease, admitted to a polivalent intensive care unit, and mechanically ventilated with Siemens Elema Servo C ventilator at constant inspiratory flow. METHOD: Peak airway pressure (Ppeak), airway pressure immediately after end inspiratory occlusion (P1), plateau pressure (P2) and intrinsic positive end-expiratory pressure (PEEPi) were measured at baseline condition and then 5, 15, and 30 min after 1 mg of salbutamol had been administered via a nebulizer through the endotracheal tube. Partial pressure of arterial oxygen (PaO2), heart rate (HR) and mean blood pressure (BP) were monitored and minimal respiratory system resistances (Rrs, m), additional resistances (DRrs) and static compliance (Cst) were computed. RESULTS: Between baseline and post-salbutamol, we observed changes in Ppeak, P1, P2, PEEPi and Rrs, m. As there were no significant differences between values at the different intervals during post administration, the results are described comparing baseline and 15 min post-salbutamol administration values. We found a significant decrease in Ppeak (4.9 +/- 0.8 cmH2O). P1 (3 +/- 0.6 cmH2O). P2 (2.1 +/- 0.6 cmH2O), PEEPi (1.9 +/- 0.5 cmH2O) and Rrs, m (1.9 +/- 0.3 cmH2O/1 s-1); DR, rs decreased in five patients, did not change in four and increased in two. HR, PaO2 and BP did not change. CONCLUSIONS: a) Salbutamol administered through the endotracheal tube by a nebulizer device lessens respiratory system resistances and airway and alveolar pressures, and therefore could decrease the risk of barotrauma and alveolar damage; b) high respiratory system resistances in ARDS have an increased smooth muscle tone component that can be reversible with salbutamol.

Adult↗
PubMed1997

MRI of a family with focal abnormalities of gyration.

Focal abnormalities of gyration (FAG) are developmental disorders that may occur in isolated patients or, as in the case being reported, as part of a familial disorder. Analysis of individuals in a family spanning three generations was carried out using MRI. Abnormalities, present in all members of generations II and III, included focal cortical dysplasia (three patients), focal cortical infolding (two patients) and schizencephaly (one patient); associated minor anomalies, such as white matter abnormalities, were seen in the remaining three members of generations II and III. MRI recognition of FAG in the family being reported proved useful in defining their phenotypical expression and providing proper counselling for individual family members.

Adult↗
PubMed1997

Hyperphosphatasemia: CT assessment.

Hyperphosphatasemia is a rare disorder of uncertain cause. A 39-year-old male exhibiting striking skeletal deformities consisting of enlargement of the skull, enlargement and bowing of the long bones, neurosensorial symptoms and elevated alkaline phosphatase is the subject of this report. In the past, the radiological workup has been limited to plain films. We advocate CT in the assessment of neurological signs and symptoms which may complicate this disease.

Adult↗
PubMed1997

Imaging features of type-B Niemann-Pick disease.

We report two cases of a mild form of type-B Niemann-Pick disease manifesting as an adult-onset chronic non-neuropathic clinical picture. Femoral T1- and T2-weighted low-intensity non-enhancing coarse bone marrow pattern was evident on femoral MR associated with splenic hypodense nodule(s) on abdominal CT. The role of imaging is discussed in relation to current techniques of confirmation of this entity based on demonstration of lipid-laden cells within marrow aspirates (which are often sea-blue histiocytes) and sphingomyelinase assay of cultured skin fibroblasts.

Diagnosis, Differential↗
PubMed1997

Radiologic features of Rhodococcus equi pneumonia in AIDS.

This report outlines the radiological features observed in three cases of Rhodococcus equi (R. equi) pneumonia in AIDS (acquired immunodeficiency syndrome) and reviews another 45 radiological reports published of this emerging opportunistic pneumonia in Human Immunodeficiency Virus (HIV) infected patients. The clinical signs in our three patients consisted in a subacute onset of respiratory symptoms and fever. A low lymphocyte count (< 200 cells/mm3), pulmonary infiltrates, and pleural effusion was present in all three cases. Cavitary pneumonia was observed in two patients, and pericardial effusion in another. In this series CD4 lymphocyte count < 200/mm3 was seen in 29 of the 48 patients (60.4%). All 48 patients had abnormal findings on chest radiographs. Abnormalities involved the upper lobes in 26 of the 48 patients (55%). Cavitation was reported in 37 of the 48 cases (77%). R. equi pneumonia may not be as the paucity of case reports suggest. Consequently, a cavitary pneumonia in HIV infected patients with a low CD4 lymphocyte count (< 200 mm3) with a subacute onset, an upper lobe predilection, and/or a poor response to conventional antibiotic therapy should be considered as suspect of R. equi infection.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Genetic heterogeneity of autosomal dominant polycystic kidney disease in Argentina.

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited disorder with genetic heterogeneity. Up to three loci are involved in this disease, PKD1 on chromosome 16p13.3, PKD2 on 4q21, and a third locus of unknown location. Here we report the existence of locus heterogeneity for this disease in the Argentinian population by performing linkage analysis on 12 families of Caucasian origin. Eleven families showed linkage to PKD 1 and one family showed linkage to PKD2. Two recombinants in the latter family placed the locus PKD2 proximal to D4S1563, in agreement with data recently published on the cloning of this gene. Analysis of clinical data suggests a milder ADPKD phenotype for the PKD2 family.

Adolescent↗