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F Izquierdo

Publications and source records attributed to F Izquierdo.

15 recordsLinked to original sources
PubMed2006

Encephalitozoon microsporidia modulates p53-mediated apoptosis in infected cells.

Microsporidia are intracellular obligate parasites which have recently been found to be related to fungi. They have a unique extrusion apparatus that is able to inject the sporoplasm directly into the target cell without using receptors. Encephalitozoon microsporidia are a source of morbidity and mortality in humans. It has been suggested that microsporidia may modulate the host cell cycle and apoptosis. We report here that caspase-3 cleavage is inhibited at different times of Vero cell infection by Encephalitozoon microsporidia and that the phosphorylation and translocation of p53 to the nucleus, previous steps for the activation of this protein, do not occur after infection of Vero cells. Consequently, the transcriptional function of p53 is impaired during the infection cycle as demonstrated by luciferase reporter assays. Thus, to our knowledge, for the first time it is shown that an intracellular parasite may be able to multiply in the host cell without activating the p53 apoptotic pathway of that cell. However, changes in the expression of Bcl-2 or Bax levels were not observed.

Animals↗
PubMed2005

First detection and genotyping of human-associated microsporidia in pigeons from urban parks.

Microsporidia are ubiquitous opportunistic parasites in nature infecting all animal phyla, and the zoonotic potential of this parasitosis is under discussion. Fecal samples from 124 pigeons from seven parks of Murcia (Spain) were analyzed. Thirty-six of them (29.0%) showed structures compatible with microsporidia spores by staining methods. The DNA isolated from 26 fecal samples (20.9%) of microsporidia-positive pigeons was amplified with specific primers for the four most frequent human microsporidia. Twelve pigeons were positive for only Enterocytozoon bieneusi (9.7%), 5 for Encephalitozoon intestinalis (4%), and one for Encephalitozoon hellem (0.8%). Coinfections were detected in eight additional pigeons: E. bieneusi and E. hellem were detected in six animals (4.8%); E. bieneusi was associated with E. intestinalis in one case (0.8%); and E. hellem and E. intestinalis coexisted in one pigeon. No positive samples for Encephalitozoon cuniculi were detected. The internally transcribed spacer genotype could be completed for one E. hellem-positive pigeon; the result was identical to the genotype A1 previously characterized in an E. hellem Spanish strain of human origin. To our knowledge, this is the first time that human-related microsporidia have been identified in urban park pigeons. Moreover, we can conclude that there is no barrier to microsporidia transmission between park pigeons and humans for E. intestinalis and E. hellem. This study is of environmental and sanitary interest, because children and elderly people constitute the main visitors of parks and they are populations at risk for microsporidiosis. It should also contribute to the better design of appropriate prophylactic measures for populations at risk for opportunistic infections.

Animals↗
PubMed1999

Staghorn calculi in children: treatment with monotherapy extracorporeal shock wave lithotripsy.

PURPOSE: We evaluated the effectiveness of monotherapy extracorporeal shock wave lithotripsy (ESWLT) for treating children with staghorn calculi. MATERIALS AND METHODS: From February 1992 to December 1997, 11 boys and 4 girls 14 months to 13 years old (median age 4 years) presented to our institution with staghorn calculi. In these patients ESWL was performed using a Siemens Lithostar-ULTRA with ultrasound stone localization and with intravenous sedation or without anesthesia. Using the Puigvert method the frequency and energy of the shock waves delivered were increased progressively to desensitize cutaneous nerve receptors, making the procedure less painful and improving stone fragmentation. RESULTS: Overall stones resolved in 11 of the 15 patients (73.3%) after an average of 2 ESWL sessions. Of the 11 patients 7 were stone-free after only 1 session, 2 with fragments less than 5 mm. required no further intervention, and 2 required additional surgery, including percutaneous nephrolithotomy to remove large residual stone fragments in 1 and open renal surgery to remove a cystine staghorn calculus in 1. Ureteral stents were not required in any patients. One case of post-ESWL fever resolved promptly with antibiotics. CONCLUSIONS: ESWL using the Siemens Lithostar-ULTRA is simple, effective and safe primary treatment in children with staghorn calculi.

Adolescent↗
PubMed1998

Sequential evaluation of serum adenosine deaminase in patients treated for tuberculosis.

STUDY OBJECTIVE: To delineate the course of serum adenosine deaminase (s-ADA) in patients with tuberculosis who are receiving effective therapy. SETTING: A medical ward and an outpatient clinic in a general hospital. PATIENTS: Twenty-five immunocompetent patients with pleural or pulmonary tuberculosis. INTERVENTIONS: All patients received standard chemotherapeutic regimens with isoniazid, rifampin, and pyrazinamide. MEASUREMENTS AND RESULTS: Six measurements of several variables, including s-ADA, were carried out at different periods of time during the 6 months of follow-up. There were no significant differences in s-ADA values between sexes and there was no significant correlation with age or with the other variables analyzed. There was a significant decline in the s-ADA values during the first 2 months in the patients as a whole (p=0.04), followed by a stabilization of the s-ADA activity. This decline was due to a marked decrease in the s-ADA in the 13 patients (52%) who had initial high levels of the enzyme (p=0.03), whereas there were no changes in those patients with normal initial levels (p=0.27). Patients with increased s-ADA activity at the time of the first measurement reported symptoms for a longer period than patients with normal s-ADA (median, 15 vs 10 days; p=0.02). CONCLUSIONS: s-ADA levels in patients with tuberculosis decrease during the initial months of effective treatment. Perhaps this decrease might reflect the normalization of the altered lymphocyte turnover induced by tuberculosis. The measurement of s-ADA could be of some help to evaluate the response to therapy, particularly in those patients with increased values of the enzyme.

Adenosine Deaminase↗
PubMed1995

[Morphopathological changes before and after biliodigestive derivation in experimental cirrhosis induced by biliary ligation in the rat].

OBJECTIVE: Study of the hepatic morphological and biochemical changes in an experimental model of cirrhosis in rat by ligation of the common bile duct before and after bilioduodenal anastomosis. DESIGN: Ligation of the common bile duct in a group of 80 female Wistar rats during 30 days. Liver biopsy for histological studies and staining, blood samples for biochemical determination were taken, and a bilioduodenal anastomosis was constructed. 30 days later new liver specimens and blood samples were taken. A control group consisted of 10 rats. RESULTS: 30 days after biliary obstruction histological changes were characterized by occurrence of bile canalicular proliferation and portal fibrosis that rounded hepatic lobules. No well-defined nodules indicative of cirrhosis were seen. There was cholestasis with an increase in serum bilirubin, alkaline phosphatase and transaminase levels, and a decrease of albumin levels. Survival was 63.7%. Thirty days after biliary diversion (60 days after ligation) the normal lobular pattern was disorganized and regenerative nodules indicative of cirrhosis appeared, separated by narrow fibrous connective tissue septa, in 65% of rats. Bilirubin levels returned to normal values. Alkaline Phosphatase and transaminase levels remained high and albumin levels remained low. Overall survival was 25%. CONCLUSIONS: 30 days after biliary obstruction there are no regeneration nodules indicative of cirrhosis. There is a precirrhotic change, biliary fibrosis. Biliary diversion does not improve the histological changes and regeneration nodules and cirrhosis appear in 65% of animals.

Anastomosis, Surgical↗
PubMed1992

[Renal hemangiomas: a clinical case and review of the literature].

Renal haemangiomas, an unusual cause of renal haematuria, are benign vascular dysplasias of uncertain etiology. Usually asymptomatic, their clinical manifestation is a unilateral renal haematuria associated or not to obstructive urological disease through accumulation of clots in the urinary tract and arterial hypertension when associated to a major arteriovenous shunt. Arteriographic diagnosis is based on the size of the vascular malformation but the absence of findings in the arteriography does not eliminate the presence of small-sized haemangiomas or microhaemangiomas responsible for the renal chronic haematuria, also labelled as "essential haematuria", which sometimes can be diagnosed through endoscopic examination of the renal cavities. This report presents one case of renal haemangioma which appeared as a massive, sudden haematuria and prompted haemodynamic instability requiring haemotherapy. Following arteriographic diagnosis, selective transarterial embolization was undertaken with three modified Gianturco's metal helicoids, to which the patient responded favourably. The report includes a review of the clinical, pathological, diagnostic and therapeutical features of renal haemangiomas.

Adult↗
PubMed1988

Percutaneous transuretero-ureterostomy in situ.

Endourological techniques allow one to postpone a second, planned intervention--urinary diversion to the intestine--in radical cystectomies with a high surgical risk. PTU consists in introducing one nephrostomy tube percutaneously through one kidney and replacing it by the definitive drainage tube during the surgical procedure after suturing both ureters together.

Aged↗
PubMed1986

Small kidney and hypertension: selection of patients for surgery.

We studied 37 patients with various degrees of hypertension and a small unilateral kidney. Renal vein renin studies were shown to be positive on 19 occasions and negative on 18. Of those positive, 10 had severe and 1 moderate hypertension. Surgery cured 63.3%. In 27% blood pressure improved and 1 patient failed to respond. Eight patients had mild hypertension with a positive renal vein renin ratio (RVRR), but on observation their home blood pressures were normal without medication and they were not considered for surgery. Eighteen patients with mild hypertension and negative RVRR were also not operated. We believe that RVRR is important for a surgical decision, but only in severe and moderate hypertensives. In mild hypertension, measurement of blood pressure at home is normal on most occasions. These are hyperreactive patients and should not have surgery, regardless of the results of their RVRRs.

Adolescent↗
PubMed1984

Renal tuberculosis and hypertension: value of the renal vein renin ratio.

We applied the central renal vein renin ratios in a group of patients with unilateral renal tuberculosis and hypertension to see whether the diseased kidney was involved in the pathogenesis of the elevated blood pressure. Of 20 patients 11 were nephrectomized, 7 had positive renal vein renin ratios and normal peripheral plasma renin activity; only 2 kept their blood pressure in control without medication. From 5 without a positive index, only 1 kept his blood pressure in control without medicine 1 year after surgery. The renal vein renin ratio has to be interpreted in light of other parameters, such as blood pressure, peripheral renin--if high the more the chance of being significant--and global renal function. The renal vein renin ratio alone per se gives poor information on the pressor role of a unilateral tuberculous kidney.

Adult↗
PubMed1975

Effects of standing position on spontaneous uterine contractility and other aspects of labor.

The aim of this paper has been to compare the uterine contractility, pain produced by contractions and comfort of the patients between standing and supine position. The study has been performed in twenty normal nulliparae who were changed from supine to standing position and viceversa at intervals of approximately thirty minutes. Intrauterine pressure and fetal heart rate were continuously monitored. Cervial dilatation was evaluated every thirty minutes. No medication was given to the patients. They were asked to assess the pain produced by uterine contractions in each one of both positions and which was the more comfortable. It has been found: 1. That the intensity of contractions was significantly higher in fifteen out of the twenty patients in standing position. 2. Frequency of contractions diminished significantly in one third of the patients. 3. Uterine activity increased significantly in half of them. 4. Consistently, less pain accompanied uterine contractions in standing position. 5. Patients reported more comfort in this position. The average duration of labor was 3 hrs 55 min. This duration is short, compared with standard clinical experience and with published data. No complications occurred, by the use of standing position during labor, on the mother or fetus. The physiological mechanisms responsible for the above mentioned effects of standing position are unknown. It is condluced that there are no clear arguments against the use of standing position during labor and that this position should be used more frequently in clinical obstetrics, provided obstetrical conditions are similar to those reported in this paper.

Adult↗