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Biomedical subjects

M Jimenez

Publications and source records attributed to M Jimenez.

At least 73 records · Page 4Linked to original sources
PubMed1997

[Cerebral abscess and cyanotic congenital heart disease].

Cerebral abscess is a classical complication of cyanotic congenital heart disease. The authors report 7 cases of cerebral abscess diagnosed since 1982. One asymptomatic patient died of a postoperative cerebral haemorrage. The child was repatriated from Africa for complete correction of his cardiac lesion. The presentation of the other 6 cases was quite typical : headaches, pyrexia and vomiting with a neurological deficit in 4 cases : two hemiparesias and two homonymous lateral hemianopsia. These 6 patients recovered without sequeilae. Four underwent surgical drainage of the abscess with antibiotic therapy. Two recovered with antibiotic therapy alone. The causal organism was only identified in patients undergoing surgical drainage and then only in 3 cases. They were gram positive cocci, in particular the streptococcus. The association ampicillin-chloramphenicol has often been proposed as the treatment of first intention. Adaptation of antibiotic therapy then depends on clinical, biological, bacteriological (CSF, blood cultures, portal of entry) outcomes and the results of CT scanning. The association of a third generation cephalosporin and an imidazole may be proposed as treatment of second intention. The minimal duration of treatment is generally acknowledged to be 4 weeks for intravenous therapy in cases of medical therapy alone, and 2 to 3 weeks in cases with surgical drainage. The age of apparition of this complication seems to be increasing as the average age was 16 in this series (cerebral abscess is classically described as occurring between 8 and 12 years of age). This may be due to palliative surgery which reduces systemic hypoxia and polycythaemia. It also appears that neurological drainage is not systematic now because of early diagnosis of this complication. Finally, in the last few years, a new population of patients is becoming more common : patients repatriated by humanitary organisations in the third world, which should incite great vigilance in the preoperative period in this pathology.

Adolescent↗
PubMed1997

Nontraumatic lower extremity amputations in diabetic and non-diabetic subjects in Madrid, Spain.

The purpose of this study was to determine the incidence of non-traumatic lower extremity amputations (LEAs) in diabetic and non-diabetic subjects in Madrid, Spain, and their direct cost. All patients who underwent LEAs between the 1st of January 1994 and the 31st of December 1996, and who had lived in area 7 of the city (569,307 inhabitants) for at least the last 6 months, were identified through operating theatre records cross-checked with Vascular Surgery Department discharge records. In addition, the direct cost of LEAs per year was estimated, taking into account the length of the hospital stay, the period of rehabilitation in the outpatient clinic after discharge, and the use of artificial limbs and their maintenance. The incidence of LEAs was 1.6 (95% CI: 1.1-2.2) per 10(5) non-diabetic subjects and 46.1 (95% CI: 34.5-57.6) per 10(5) diabetic patients. Relative risk was 28. Total direct costs associated with LEAs per year were US$ 56,131 in the diabetic population and US$ 30,765 in the non-diabetic population. Thus, potential cost savings associated with excess amputations in the diabetic population was estimated at US$ 541,353 per year of US$ 94,736 per 10(5) inhabitants. It is concluded that the incidence of LEAs in both diabetic and non-diabetic populations in area 7 is the lowest reported in European countries. The potential cost savings per 10(5) inhabitants and per year is estimated at US$ 94,736.

Adult↗
PubMed1996

The proto-oncogene product c-Crk associates with insulin receptor substrate-1 and 4PS. Modulation by insulin growth factor-I (IGF) and enhanced IGF-I signaling.

The Crk proto-oncogene product is an SH2 and SH3 domain-containing adaptor protein which we have previously shown to become rapidly tyrosine phosphorylated in response to stimulation with insulin-like growth factor I (IGF-I) in NIH-3T3 cells. In order to further characterize the role of Crk in the IGF-I signaling pathway, NIH-3T3 and 293 cells were stably transfected with an expression vector containing the Crk cDNA. The various resultant 3T3-Crk clones expressed Crk at approximately 2-15-fold higher levels than parental 3T3 cells. In 3T3-Crk cells, Crk immunoreactivity was detected in insulin receptor substrate-1 (IRS-1) immunoprecipitates. Stimulation with IGF-I resulted in a dissociation of Crk protein from IRS-1. In contrast, the association of the related adaptor protein Grb2 with IRS-1 was enhanced by IGF-I stimulation. Similar results were obtained in stably transfected 293-Crk cells, which express both IRS-1 and the IRS-1-related signaling protein 4PS. In these cells, IRS-1 and 4PS both associated with Crk, and this association was also decreased by IGF-I treatment, whereas the association of Grb2 with IRS-1 and 4PS was enhanced by IGF-I. Overexpression of Crk also enhanced IGF-I-induced mitogenesis of NIH-3T3 cells, as measured by [3H]thymidine incorporation. The levels of IGF-I-induced mitogenesis were proportional to the level of Crk expression. These results suggest that Crk is a positive effector of IGF-I signaling, and may mediate its effects via interaction with IRS-1 and/or 4PS.

3T3 Cells↗
PubMed1996

Leishmaniasis presenting as a dermatomyositis-like eruption in AIDS.

Three patients are described with leishmaniasis and AIDS, with cutaneous lesions mimicking dermatomyositis. Leishmania organisms were observed in great numbers in the dermis of lesional skin biopsy specimens. They were also present inside keratinocytes in all layers of the epidermis in one patient. Skin cultures from all patients and bone marrow culture in patients 1 and 3 revealed Leishmania infantum. Leishmania organisms were also found in nonlesional skin. The absence of proximal symmetric muscle weakness, elevated muscle enzymes, myopathic electromyograms, or characteristic histopathologic and immunologic features of dermatomyositis, and the rapid and complete clearance or marked improvement of the cutaneous lesions after treatment for leishmaniasis, make us consider true dermatomyositis unlikely. We suggest that leishmaniasis be included in the list of diseases capable of inducing a dermatomyositis-like eruption.

AIDS-Related Opportunistic Infections↗
PubMed1996

Renal dysplasia in a Rhodesian ridgeback dog.

A six-month-old Rhodesian ridgeback dog was presented for evaluation of facial swelling. Chronic renal failure was clinically diagnosed based on urinalysis, biochemical changes and ultrasonography. The facial swelling was due to fibrous osteodystrophy, which was evident on survey radiographs of the skull. On post mortem examination, chronic renal failure as a result of renal dysplasia was confirmed. This is the first reported case of renal dysplasia in this breed of dog.

Animals↗
PubMed1996

Overnight growth hormone secretion in achondroplasia: deconvolution analysis, correlation with sleep state, and changes after treatment of obstructive sleep apnea.

The normal profile for overnight GH secretion in achondroplasia has not been previously studied. Factors that have been shown to influence GH secretion include age, obesity, sleep state, and the presence of obstructive sleep apnea (OSA). We assessed GH levels in a group of subjects with achondroplasia, during overnight polysomnography. Nineteen subjects with achondroplasia were studied at 11.3 y of age (median 6.7, range 1.8-30.9). Levels of GH were measured using time-resolved immunofluorometric assay (DELFIA, Pharmacia Biotech Inc.) and analyzed by a deconvolution method. Five subjects were restudied after treatment for OSA. Secretion rates of GH were greater in slow wave (SWS) and rapid eye movement (REM) sleep than in stage one and two (SI-II = light non-REM) sleep (p < 0.01). Total overnight GH secretion decreased with increasing age (r2 = 0.22 p < 0.04). Neither the frequency of arousals, frequency of sleep state transitions nor the severity of OSA correlated with measures of GH secretion. Levels of IGF-I correlated independently with age, body weight (percent ideal), and GH secretion rate (r2 = 0.76, p < 0.001). In a group of five subjects treated for OSA, improved respiratory distress index and reduced sleep state transitions were not associated with significant changes in GH secretion rate by sleep stage; SWS [from 0.62 +/- 0.28 mIU/L/min to 1.02 +/- 0.25 mIU/L/min (NS)] and SI-II sleep [from 0.26 +/- 0.07 mIU/L/min to 0.60 +/- 0.16 mIU/L/min (NS)]. However, in those five subjects, a GH secretion peak during the first 2 h of SWS was initially absent, appearing only after treatment of OSA (1.09 +/- 0.38 mIU/L/min) compared with (2.40 +/- 0.59 mIU/L/min (p = 0.01). A profile of overnight GH secretion is presented for subjects with achondroplasia.

Achondroplasia↗
PubMed1996

[Percutaneous dilatation of the pulmonary tract in tetralogy of Fallot].

When palliative treatment is indicated in tetralogy of Fallot, percutaneous endoluminal dilatation of the valvular pulmonary stenosis may represent an alternative to palliative surgery (systemico-pulmonary shunt) and its disadvantages. This paper sets out the clinical outcome and growth of the pulmonary arterial circulation after dilatation of the valvular pulmonary stenosis in children with tetralogy of Fallot. Twenty-five children (average age: 8 +/- 5.8 week; average weight: 6.7 +/- 2.4 kg) were included in this study. The dilatation resulted in an immediate decrease in the patients' cyanosis and a significant increase (+10%) in arterial oxygen saturation. However, this technique did not suppress the risk of anoxic malaise. Only 5 children (20%) required a palliative surgical shunt for persistence of anoxic malaise. From the anatomical point of view, the dilatation induced significant growth of the pulmonary annulus (7.6 mm vs 11.3 mm; p < 0.0001), of the main pulmonary artery (6.8 mm vs 10 mm); p = 0.008) and left pulmonary artery (7 mm vs 11 mm; p = 0.02). The need for a procedure to widen the right ventricular outflow tract at the time of complete correction was also reduced. The perioperative mortality of complete correction and postoperative pulmonary insufficiency were decreased. Percutaneous dilatation of the right ventricular outflow tract is therefore a valuable palliative alternative to surgical sytemico-pulmonary shunt.

Blood Gas Monitoring, Transcutaneous↗
PubMed1995

Review of the long-term course of 52 patients with pulmonary atresia and ventricular septal defect. Anatomical and surgical considerations.

This study reviews the long-term course of 52 patients with pulmonary atresia and ventricular septal defect seen in a single institution and followed for a mean period of 8.6 years (range 2 days to 20 years). Before the first operation, pulmonary blood supply was provided by ductus arteriosus supplying confluent pulmonary arteries in 26 patients (50%, group I), and was partially or entirely dependent on systemic collateral arteries in the other 26 patients (group II). The angiographic mean ratio of diameters of the right and left pulmonary artery/descending aorta (McGoon ratio) was significantly lower in group II than in group I, 0.76 +/- 0.42 vs 1.04 +/- 0.17 (P = 0.006). Severe arborization defects (with fewer than 10 pulmonary vascular segments connected to central pulmonary arteries) were present only in group II patients (eight patients: 15%), six of whom had congenital absence of the central pulmonary arteries. Corrective surgery was performed in 23 patients (44%, 14 in group I, nine in group II). All but one, who died later, had a McGoon ratio > or = 1 (mean 1.19 +/- 0.18) at time of repair. There was one hospital death (4%) and two late deaths (9%). All but one of the surviving corrected patients were in functional class I or II. Conduit replacement reoperation was performed in three patients (14%), 6, 10 and 13 years, respectively, after repair. At the end of the study, among the 37 patients (71%) who were alive (17 in group I, 20 in group II), 20 (39%) were corrected (12 in group I, eight in group II), four await corrective surgery, and six (11.5%) are estimated inoperable (all in group II) because of very hypoplastic or absent pulmonary arteries. This study confirms the estimated rate in the published literature of long-term survival in patients with pulmonary atresia and ventricular septal defect, and the good results of corrective surgery whenever the size and distribution of pulmonary arteries are satisfactory. The problem of very hypoplastic pulmonary arteries and severe arborization defects remains contentious.

Adolescent↗
PubMed1995

[Comparative value of transthoracic echocardiography and angiography for measuring the pulmonary artery annulus in tetralogy of Fallot].

It may be necessary to perform an enlarging pulmonary annuloplasty during surgical cure of Tetralogy of Fallot (TOF) in order to optimise reconstruction of the right ventricular outflow tract. As this additional procedure implies an increase in perioperative mortality, it is useful to prepare for this eventuality before surgery. Two imaging techniques are available: transthoracic echocardiography (diameter of the pulmonary annulus obtained by averaging the measurements obtained in the subcostal and parasternal short axis views of the insertion of the pulmonary valve cusps at end systole) and selective angiography during right heart catheterisation (anteroposterior measurement with comparison to be projected and real size of the catheter at the point of insertion of the cusps at end systole). In this study, these two techniques were compared with reference to the peroperative measurement with Hegar dilators and criteria defined by Naito (minimal diameter of the pulmonary artery annulus with respect to the weight of the child). Seventy-eight children admitted to hospital between January 1986 and April 1994 for curative surgery of TOF were included. The calculation of the intra-class correlation coefficient showed a mediocre correlation with angiography and a very mediocre correlation with echocardiography compared with peroperative measurements. However, the calculation of sensitivities showed angiography to be the predictive investigation for annuloplasty in children not conforming to the Naito criteria: higher sensitivity (83% vs 26% for echocardiography), greater negative predictive value (84% vs 70%). This result holds for all categories of body weight (over and under 10 kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗
PubMed1995

[Antiphospholipid syndrome in children. Apropos of a case].

The authors report the case of a 10 year old child who presented with an uncomplicated deep venous thrombosis associated with an antiphospholipid syndrome. The diagnosis was established by the finding of spontaneous prolongation of the activated cephalin time, the finding of a lupus-like antibody and an anti-cardiolipin antibody. The clinical outcome was good with oral anticoagulants but a recurrence was observed when they were stopped. The authors discuss the question of the duration of preventive therapy.

Age Factors↗
PubMed1994

Bacterial translocation in cirrhotic rats. Its role in the development of spontaneous bacterial peritonitis.

Bacterial translocation occurs in ascitic cirrhotic rats, but its association with ascites infection is unknown. The aim of this study was to assess the relation between bacterial translocation and ascites infection in cirrhotic rats. Male Sprague-Dawley rats were induced to cirrhosis with intragastric CCl4. Ascitic fluid, portal and peripheral blood, mesenteric lymph nodes, liver and spleen samples were cultured before death in those cirrhotic rats with less (group A) or more (group B) than 250 polymorphonuclear neutrophils/mm3 in ascitic fluid, as well as in healthy control rats. Histological examination of jejunum, ileum, and caecum was also performed. Bacterial translocation occurred in 45% of ascitic rats (without differences between groups A and B), but in 0% controls (p = 0.01). Bacterial translocation was associated with positive ascitic fluid culture in 60% of the cases. In all of them the same bacterial species was isolated in both mesenteric lymph node and ascitic fluid. Submucosal caecal oedema (100%), ileal lymphangiectasia (41%), and caecal inflammatory infiltrate (41%) occurred in ascitic rats, the last being associated with ascitic fluid positive culture (p = 0.04). These results suggests that bacterial translocation occurs frequently in ascitic cirrhotic rats, and may play a permissive, but not unique, part in a number of ascites infections. Whether histological changes seen in cirrhotic ascitic rats favour bacterial translocation remains to be elucidated.

Animals↗
PubMed1994

Rhythmic oscillating complex: characterization, induction, and relationship to MMC in chickens.

Migrating myoelectrical complexes (MMCs) and rhythmic oscillating complexes (ROCs) have been investigated in chickens prepared for electromyography. Animals were chronically implanted with electrodes in stomach, duodenum, jejunum, ileum, ceca, and rectum. MMCs showing phases I-III were found in the jejunum and ileum both in fed and fasted states. Repetitive spike bursts were recorded in the duodenum (0.5-1/h), disrupting the gastroduodenal coordination and preceding a phase III in the jejunum. ROCs appeared spontaneously in fasted animals and in 75% of the recordings during the dark period. Four consecutive intestinal myoelectrical patterns have been described during a ROC. Briefly, they consisted in series of high-speed propagated abroad contractions of great amplitude that progressively changed into others of orad direction. In relation to the MMC, the ROC pattern appeared just after a phase III reached the distal ileum, and a pattern of duodenal repetitive spike bursts, followed by a migrating phase III in the jejunum, started at the duodenum after a ROC. No myoelectrical changes were recorded in cecorectal activity during ROC. Vagotomized animals showed the ROC pattern. Neither apomorphine (5-100 micrograms/kg iv) nor cholecystokinin (10(-9) mol/kg iv) induced ROCs. Naloxone (5 x 10(-7) mol/kg iv) and atropine (0.1 mg/kg iv) induced isolated orad contractions. Myoelectrical and functional similarities can be found between retrograde giant contractions, described in mammals, and ROCs. However, they differ in their origin and mechanism of induction.

Animals↗
PubMed1994

Detection of hepatitis C virus RNA in hemodialysis patients.

The clinical significance of the high prevalence of antibodies to hepatitis C virus (HCV) in dialysis patients remains undefined. In order to assess the relationship between seropositivity and potential infectivity, 63 patients undergoing maintenance hemodialysis were evaluated between April and May 1990. The mean duration of maintenance hemodialysis was 45 mo (range, 13 to 144). Eighty-two percent (52 of 63) had received blood transfusions, and 16% (10 of 63) had a history of iv drug abuse. Serum samples were analyzed by HCV-cDNA polymerase chain reaction; antibodies to HCV structural (core) and nonstructural regions NS3 and NS4 were determined by enzyme immunoassay. Specimens repeatedly reactive for anti-HCV and HCV-RNA-positive samples were tested by HCV MATRIX dot immunoblot assay and HBV-DNA PCR. Twenty-five percent (16 of 63) were anti-HCV-positive. Of the 16 anti-HCV-positive patients, HCV-RNA was detected in 5 (31%) with the NS3 primers and in 12 (75%) with 5'-noncoding primers. Among the anti-HCV-negative patients, HCV-RNA was detected in 2 (4.3%) of 47 patients. Eleven of the 18 patients with HCV infection (anti-HCV and/or HCV-RNA-positive) had evidence of additional present or past viral infections (human immunodeficiency virus and/or hepatitis B virus). In summary, HCV-RNA is present in at least 75% of anti-HCV-positive patients, suggesting that they may be infectious. The detection of HCV-RNA in anti-HCV-negative patients may indicate early or chronic HCV infection not detected by current antibody assays or the inability of these patients to mount or sustain a significant antibody response.

Adult↗
PubMed1994

Visceral leishmaniasis in Angola due to Leishmania (Leishmania) infantum.

A 26-year-old man from Angola with no history of travel outside the country presented with typical symptoms of visceral leishmaniasis. The parasite was isolated and biochemically characterized using both kinetoplast DNA and nuclear DNA probes and showed a strong homology with Leishmania (Leishmania) donovani sensu lato (s.l.). When the nuclear DNA of the isolate was hybridized with a specific Leishmania (L.) infantum probe, the pattern obtained showed a clear signal with this species. To establish its identity more specifically, this isolate was typed using a 15-system isoenzyme panel and thick-starch gel electrophoresis, and was identified as L. (L.) infantum zymodeme 1 (MAD-1), the most widespread zymodeme in Mediterranean countries. One case of visceral leishmaniasis has been reported in Angola, but this case is the first report of L. (L.) infantum in Africa south of the equator.

Adult↗
PubMed1994

[Lethal hydrops fetalis secondary to an umbilical cord hemangioma].

We report an umbilical cord hemangioma associated with an hydrops fetalis and detected by ultrasonography at 21 week's gestation. Because of the fetal distress, a caesarean section was performed at 28 weeks'. The infant died soon after birth despite resuscitation. The post-mortem examination showed an extensive accumulation of serous fluid in the fetal tissues and the body cavities, and major pulmonary hypoplasia. The umbilical cord contained a grossly fusiform tumor which fulfilled the pathological criteria of an umbilical cord hemangioma. Umbilical cord hemangiomas are very unusual tumors and are rarely associated with a fetal hydrops. This tumor is a cause of increased maternal serum and amniotic fluid alpha-foetoprotein levels. Although it is usually isolated, it is imperative to search for associated malformations or angiomas that may clinically manifest later.

Fatal Outcome↗
PubMed1993

Mechanism of action of CCK in avian gastroduodenal motility: evidence for nitric oxide involvement.

Our objective was to study the mechanism of action of cholecystokinin (CCK) on the motility of the gastroduodenal area. Chickens were implanted with five electrodes for electromyography in the stomach and duodenum. The effects of CCK (10(-9) mol.kg-1.10 min-1) were studied against the presence of several antagonists and in vagotomized animals. CCK caused inhibition of gastric motility and duodenal hyperactivity. Vagotomy blocked CCK responses in the stomach but not in the duodenum. Hexamethonium partially blocked gastric inhibition induced by CCK. NG-nitro-L-arginine methyl ester blocked the inhibitory response to CCK in the stomach but did not modify duodenum response. L-Arginine did not modify CCK actions. Opioid antagonists naloxone and naltrindole and adrenergic antagonists phentolamine and propranolol did not modify CCK response. Atropine did not modify duodenal response to CCK. Sodium nitroprusside (10(-8)-10(-6) mol/kg) inhibited gastroduodenal activity in a dose-related manner. We suggest that gastric response to CCK is vagally mediated, mainly by the nitric oxide system. Duodenal hyperactivity seems to be a direct action of CCK. Nitric oxide is a putative neurotransmitter in the chicken gut.

Animals↗
PubMed1993

Immunohistochemical differentiation of gastrin and cholecystokinin in gastrointestinal tract of chickens.

The presence of cholecystokinin (CCK) in the gastrointestinal tract of chickens has not been well demonstrated, although immunological and chromatographic techniques have shown the presence of intestinal gastrin-CCK-like factors. Recently, a new peptide, structurally related to mammalian CCK, but with a gastrin-like activity, has been isolated from the digestive tract of chickens. The objective of this work has been: 1) to study the presence of gastrin-CCK-like immunoreactivity (IMR) in the digestive tract of chickens; 2) to distinguish chicken gastrin from CCK; and 3) to establish their distribution using specific antibodies. Tissue specimens from the proventriculus, gizzard, pylorus, duodenum, jejunum, ileum, ceca, and rectum were studied using indirect immunofluorescence procedures. The antibodies used were: 1) an antibody specific against the C-terminal pentapeptide common to gastrin and CCK; 2) one specific against CCK-33; and 3) one specific against chicken gastrin. Their use allowed the differentiation of two cellular populations which showed different affinities for the antibodies, indicating the presence of a gastrin-like peptide in the antrum and another CCK-like peptide in the small intestine, with the highest concentration in the proximal ileum. Immunoreactivity was not found in any other studied area. Two different peptides of the gastrin-CCK family are present in the chicken's gastrointestinal tract. However their differentiation and identification are more difficult than in mammals due to the greater structural similarities of these peptides in birds.

Animals↗