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M Asensio

Publications and source records attributed to M Asensio.

At least 19 recordsLinked to original sources
PubMed2006

Variable very-high-energy gamma-ray emission from the microquasar LS I +61 303.

Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes.

Journal Article↗
PubMed2006

[Sigmoid colon vaginoplasty: experience with five cases].

Vaginal atresia compounds a rare congenital anomaly and results from anomalies in the development of Müller ducts as happens in the Mayer-Rokitansky syndrome or in other cases of intersexual states. Some different tissues have been issued for the creation of a neovagina, but none of them has been accepted as ideal. We have chosen sigmoid colon in order to create a new vagina functionally appropriate. We present five cases affected of vaginal atresia. Two of them were Mayer-Rokitansky syndromes and the other were diagnosed during the study for primary amenorrhea as a result of an intersexual state. In all cases a vaginoplasty was performed according to Baldwin's technique in the ages between 15 and 20 year-old. The follow up has been from 1 to 16 years. No postoperative complications have been observed. The external aspect of the genitalia is normal and a proper sized with length and lubrificated vagina was attained in all cases without any retraction in any patient. Two of the patients maintain sexual relations without problems. In our experience, the cosmetic and functional result of sigmoid vaginoplasty were excellent.

Adolescent↗
PubMed2004

[Good results with Passerini's technique in severely masculinised female pseudohermaphroditism].

In female pseudohermaphroditism due to congenital adrenal hyperplasia (CAH), some cases develope a very important masculinization degree with a high outlet of the vagina above the outern urethral sphincter. There are several surgical techniques to solve this problem. Our group uses Passerini's thecnique since 1990. 9 Girls with CAH with extreme masculitation (IV and V Prader degree) have been operated with this technique. The age at intervention varies between 9 months and 3 years, with a follow-up between 1 and 12 years. All these patients had hormonal studies, demostrating a deficiency of 21-hydroxilase in 8 cases and a deficiency of 11-B-hydroxilase in one case. To determine the vaginal outlet a genitography was performed in all cases, vaginoscopy in 7 cases and MNR in 2 cases. Passerini's technique consists of two phases: the first step has the objective of forming the distal 2/3 of the vagina using the skin and the urethral mucosa of the phallus. At the second time transtrigonal way is performed to access the vagina which is desinserted from its urethral outlet and anastomosed with the distal neovagina. There were no significative complications in immediate time. The esthetic result is acceptable in all cases, although one case had to be surgically repaired because of a prominent vulvar flap. We use vaginoscopy to prove vaginal permeability in all cases although one of them developed adherences around the anastomosis. This severe genital malformation, very uncommon, has a difficult surgical solution. Passerini's technique allows, with less complications, to create an acceptable outer genitals at early age and only in one surgical time.

Adrenal Hyperplasia, Congenital↗
PubMed2003

Outcome of 28 split liver grafts.

UNLABELLED: Our aim is to present our experience with split liver transplantation. From 1992-2002, 14 livers were split to obtain 28 grafts that were transplanted to 12 adults and 16 children. Ex situ splitting was performed in all cases. The left graft consisted of the left lateral segment (segments II-III) in 11 cases and the left lobe in three, depending on the size of the pediatric recipient. Pediatric recipients were of mean age 3, 4 years; mean weight 13 kg; six emergency cases for fulminant hepatic failure or urgent retransplantation and seven of 10 elective cases for biliary atresia. Postoperative mortality rate was 31% (five cases), including four of six emergency cases and one elective case (10%). The main cause was multiorgan failure. Technical complications were: one arterial thrombosis, one portal vein thrombosis, and four biliary complications. Eleven patients are alive and well. Adult recipients were of mean age 53 years. The indications were hepatocellular carcinoma in six cases, liver cirrhosis of various etiologies in five, and one recurrence of hepatitis C in a graft. Two patients died during the postoperative period from sepsis after retransplantation for primary nonfunction of the split graft and multiorgan failure with sepsis. One-year actuarial survival was 84%. CONCLUSIONS: The results of split liver transplantation in elective cases are similar to whole liver transplantation, whereas patient survival among emergency cases is low due to the critical condition of the patients.

Adult↗
PubMed2003

[Endoscopic treatment of tracheo-esophageal fistulas: fact or fiction?].

Tracheo-esophageal fistulas as a sequelae of esophageal atresia surgery are usually a severe complication whose correction requires an important surgical aggression, often with uncertain results. The possibility of treating this problem through the use of non-aggressive endoscopic methods has been described in medical literature over the last years, applying several products for occlusion with conflicting results in different publications. We present three cases of tracheo-esophageal fistulas, describing the technique of trans-tracheal endoscopic approach based on the novelty of employing a laryngeal mask which facilitates ventilation during the procedure, as well as the possibility to use endoscopic material of greater diameter. We comment on the different occlusion materials employed (Tissucol & Histoacryl) and the difficulties of their management. In one case two attempts of occlusion were made, and three in the other two, varying the application method and product. In two cases the fistulas initially reopened and in the other an occlusion was demonstrated by esophagogram and remission of respiratory symptoms during eight months was achieved. In a posterior control, a thread-like fistula reappeared but did not affect clinical improvement. The possibility to employ endoscopic techniques always seemed very promising for this type of pathology. The appearance on the market of various substances with capacity of occlusion has allowed us to employ them in comparative studies and simultaneously test the efficacy of the laryngeal mask in this kind of situations. The results show the complete ineffectiveness of some of these products and the relative possibilities of others, although in our experience we have yet to achieve any definitive occlusion.

Child↗
PubMed2001

[Treatment of caustic stenosis of the esophagus with self-expanding devices].

Caustic stenosis is a serious problem in children due to its complicated resolution and implications in important areas like nutrition, as well as the child's tolerance to the measures taken to correct them. After dealing extensively with this problem over the last twenty five years, always from a conservative approach using traditional methods like dilatations, we believe we have found a technique that brings together all the necessary conditions to achieve a favorable and definitive solution. Our ideal goal to achieve a device that provides a well-tolerated permanent esophageal expansion during the scarring process, also permitting normal swallowing, seems to have been reached through the use of the new generation of silicone stents. The authors present their experience in the first seven cases of caustic stenosis treatment through the placement of silicone stents, describing a precise placement technique while establishing a standard protocol for the use of these devices.

Adolescent↗
PubMed2001

[Nineteen years experience with posterior sagittal anorectoplasty as a treatment of anorectal malformation].

UNLABELLED: Posterior sagittal anorectoplasty (PSARP) is considered today the best surgical technique for the treatment of the anorectal malformations. With the aim of evaluating the results of the PSARP in our patients, the charts of 39 children (27 male, 12 female) were reviewed. Mean age was 11 years (3 to 20 years) and the mean follow-up period from the closure of the colostomy was 9.4 years (1 to 18 years). Patients with any alteration of the extrinsic innervation or those with rare malformations were excluded of the study. According to the Wingspread classification, 14 patients had a high defect, 13 had an intermediate type and 12 had a low one. One patient had a PSARP in the newborn period whereas the rest of them had a descending loop colostomy. Definitive repair consisted in PSARP in low and intermediate forms and in six of the high type patients. The rest (8) of the high type patients had a Rehbein abdominoperineal pull-through (DA) plus a PSARP. Evaluation for the surgical results was made by means of an anorectal manometry (existence or not of anal inhibitory reflex [RIA], the symmetry and pressure of the canal anal, and the existence of extrinsic innervation) and a clinical questionnaire. Patients or parents were asked for fecal continence, age at which the continence was achieved and the existence of severe constipation. RESULTS: Low defects: Eleven patients were continent between 3 and 5 years old. Seven patients had RIA. Intermediate defects: Seven patients were continent. Five (all with RIA) achieved continence between 2 and 8 years old; the other 2 were continent at the age of 10. The six incontinent patients had absence of RIA and/or low-pressure anal canal. High defects: Five patients were continent, between 11 and 16 years old. All had an DA plus PSARP. None of them had RIA. All the incontinent patients had an anomalous anal canal. CONCLUSIONS: The lowest the type of an anorectal malformation, the better the prognoses. In these patients, there is a relationship between the achievement of continence, the presence of RIA and the symmetry and high pressures at the anal canal. Among the patients with high defects, the results are better when they had an abdominoperineal pull-through plus PSARP.

Adolescent↗
PubMed2001

[Comparative study of reduced-size and whole liver transplantation in children].

It is difficult to find adequate donors for many children with low weight. In order to increase the pool size of donors and decrease mortality on the waiting list, several reduction techniques have been developed in the last years (reduced, segmental and split liver). The aim of this study is to compare morbility and mortality in our serie between children who received a full-size liver and those who received a partial one. We retrospectively compared 27 cases of reduced-size liver transplants (RLTx) with 102 cases of full-size liver transplants (FLTx) performed between june of 1985 and february of 2000. Mean age in RLTx was 38.1 months (range 6-144) vs 70.8 months (range 5-192) in FLTx. Mean weight was 11.9 k (range 5.8-30) in RLTx vs 20.48 k (range 4.4-68) in FLTx. Mean donor/recipient body ratio was 4.88 in RLTx and 2.03 in FLTx. The indication of transplantation was urgent in 14 patients (51.8%) from the RLTx group and in 12 (11.7%) from the FLTx one. The requirements of transfusions during surgery was greater in the RLTx (177 cc/kg of RBC transfusions vs 124 cc in FLTx). There was no differences between both groups regarding other postoperative complications (portal thrombosis, need of reintervention and biliary complications). Arterial thrombosis was observed only in FLTx (12 cases). Graft survival at 3 months was 49% for the RLTx and 73% for the FLTx. It was 43% and 67%, respectively, at 1 year, and 43% and 53% at 5 years after liver transplantation (p = 0.06). If we consider only elective transplants, survival was 72% for RLTx and 75% for the FLTx at 3 months. Although survival is lower in the RLTx group, the difference is not significant. If we consider only the elective transplants, survival is almost the same in both groups. The reduction techniques are a good method to decrease mortality in the waiting list without increasing post-transplant morbidity and mortality.

Child↗
PubMed2000

Analysis of risk factors following pediatric liver transplantation.

Several recipient, donor and operation factors as well as postoperative complications related to patient survival after liver transplantation (LT) in children were studied by univariate and multivariate analyses. In a 13-year period, 103 patients under 15 years of age underwent 120 LT; the mean age was 63 months and 36% were under 2 years of age. Indications for LT were cholestatic disease in 68 (56%), metabolic diseases in 18 (14%), fulminant hepatic failure in 8 (7.5%), cirrhosis in 7 (5.8%), and retransplants in 17 (14%). Whole liver was transplanted in 79% of cases and partial liver in 21%. Actuarial survival at 1, 5, and 10 years was 70%, 61%, and 57%, respectively. United Network of Organ Sharing (UNOS) I recipients (RR = 2.7), primary non-function (PNF) (RR = 13.9), and hepatic artery thrombosis (HAT) (RR = 3.8) were independent factors for lower patient survival in multivariate analysis. Thus, in our experience, postoperative mortality as a consequence of the patient's condition before transplantation, or complications such as PNF or HAT, are the major causes of decreased survival in pediatric LT.

Adolescent↗
PubMed2000

Mealiness assessment in apples and peaches using MRI techniques.

Mealiness (woolliness in peaches) is a negative attribute of sensory texture that combines the sensation of a desegregated tissue with the sensation of lack of juiciness. In this study, 24 apples cv. Top Red and 8 peaches cv. Maycrest, submitted to 3 and 2 different storage conditions respectively have been tested by mechanical and MRI techniques to assess mealiness. With this study, the results obtained on apples in a previous work have been validated using mathematical features from the histograms of the T2 maps: more skewed and the presence of a tail in mealy apples, similar to internal breakdown. In peaches, MRI techniques can also be used to identify woolly fruits. Not all the changes found in the histograms of woolly peaches are similar from those observed in mealy apples pointing to a different underlying physiological change in both disorders.

Food Technology↗
PubMed2000

[Bile duct atresia: outline for a solution].

UNLABELLED: Biliary atresia continues to be a serious and relatively rare disease (1/50,000 newborns) and whose long-term prognosis has changed drastically since the appearance of liver transplant (LT) as a therapeutic weapon. The combination of two factors, early diagnosis and correct application of Kasai's surgical technique, is essential to obtain acceptable results and sufficient biliary drainage allowing the children to overcome the critical 7 kg barrier and place them in the lesser morbi-mortality range in relation to a possible LT. But we must keep in mind that despite its critics, Kasai's technique can guarantee, both in our own experience and in the literature, ten years survival percentages over 50% with correct hepatic function, as well as clinical normality and a quality of life clearly superior to first years post-LT. We present the evolution of a group of 20 patients affected with biliary atresia, diagnosed in our center since 1985, the year when pediatric LT began to be used as a therapeutic procedure in this country. We valued the age of intervention, technique, immediate and long-term results and the evolution and necessity of LT. All 20 patients were analyzed individually, and they currently have an age range from 2-14 years and were all operated by Kasai's technique. We classified the patients as having good, regular or poor results with regards to biliary flow, normalization of billirubin levels and clinical evolution. Sixteen patients presented biliary flow of such an extent that 14 of them, classified as good, completely normalized the billirubin levels. Two others, presently aged 14 and 8 years respectively, present average levels of 2.5-5.5 mg/100 ml and are classified as regular in a situation of advisable transplant, although with an acceptable hepatic function. Only one case, the first in the poor group, did not initially present biliary elimination and died at age six months while on the waiting list. Three other cases in the same group presented insufficient biliary elimination and were transplanted with 7, 11 and 12.5 kg, respectively. The second died in the first year post-transplant. CONCLUSIONS: In our opinion, action in biliary atresia must be early and based on the correct application of Kasai's technique, seeking to achieve a biliar flow that eliminates or distances the patient as far as possible from the necessity of a future LT. Three lines come together to obtain this target: an early diagnosis, a correct application of Kasai's technique, and an implication in the follow-up and treatment of these children by the hepatic transplant groups. All this advises us, as is done in other countries, to create reference centers for the study of neonatal cholestasis where an accumulated experience of a relatively rare pathology can be taken advantage of.

Adolescent↗
PubMed1999

Conservative treatment of caustic esophageal injuries in children: 20 years of experience.

The authors present their experience in the medical treatment of 1, 296 caustic esophageal injuries in children over the last 20 years in two study groups, one comprising the period up to 1989 and the other 1990 to 1996, comparing the different treatments used in each group. The treatment was based fundamentally on dilatations with anterograde mercury bougies, Savary bougies, or retrograde thread-guided bougies with gastrostomy. Pneumatic balloons or stenting procedures have also been employed in the last 3 years. Early fiberendoscopy was used systematically in the second group, which provides a more accurate evaluation of the esophageal lesions. Antibiotic coverage was done systematically during the first 10 days in all serious cases, while steroids were employed routinely only in the last 3 years. The results were similar in both groups, with a dilatation average of 32 in the first and 30 in the second group and an initial dilatation interval of 3 to 4 weeks in both. Using updated exploration and dilatation techniques, we drastically reduced the number of gastrostomies needed for retrograde thread-guided dilatations from 51 in the first group to 5 in the second, consequently improving the patients' life quality. There was no mortality and only five esophageal perforations, which did not require surgical treatment.

Anti-Bacterial Agents↗
PubMed1999

[Intraesophageal stent in the prevention of stenosis caused by caustic ingestion].

Esophageal stenosis is a frequent consequence of lye ingestion, and their treatment is of longstanding and complex matter. The search of new solutions for this problem is challenging and always attractive if its associated with less aggressiveness to the patient. The use of intraesophageal stents is not new in the treatment of stenosis, but it was anecdotal, until histocompatible material came out in the market. The stent is designed in the OR, having the same length as the stenosis, previously observed by endoscopy, its made out of a silicone tube 30 or 36 French, mounted over an ng tube 16, all this is fixed in the ends of the silicone tube, that way won't slip over the ng tube. It is placed with a laryngoscope assistant, the proximal end of the ng tube comes out the nasal nares. Once the location of the tube is checked, the stent is left in place for six weeks. Our experience, with seven patients, has shown excellent tolerance to the stent; at the third post procedure day the patients were eating soft diet by mouth, we believe that the esophageal spasm had resolved by this day. Once the stent was withdraw, five cases were free of esophageal lesions, in the other two small areas of bleeding were visualized. In the follow-up the five cases that were free of lesions, had a normal esophageal diameter, in the other two, one had a moderate restenosis and the other case was severe.

Age Factors↗
PubMed1997

Simultaneous detection and typing of plum pox potyvirus (PPV) isolates by heminested-PCR and PCR-ELISA.

Two techniques for simultaneous detection and typing of plum pox potyvirus (PPV) isolates belonging to the D or M serotypes, heminested PCR (H-PCR) and PCR-ELISA, have been developed. Ten PPV isolates typed using PPV-D and PPV-M specific monoclonal antibodies by ELISA-DASI were used to validate these two methods. The results obtained show a complete coincidence of the nucleic acid-based techniques with the serological data. When serial dilutions of infected plant extracts were assayed, H-PCR and PCR-ELISA were found to be 100 times more sensitive than the more conventional immunocapture-PCR (IC-PCR) assay. Testing of 228 PPV-infected fruit tree samples coming from different hosts and locations indicated that so far only PPV type D appears to be present in Spain and in Chile. Coupled with print-capture sample preparation (Olmos et al., Nucl. Acids Res. 24, 2192-2193, 1996) the increased sensitivity provided by heminested-PCR allowed the detection of PPV targets of D and M types, in wingless individuals of the aphid vector Aphis gossypii.

Amino Acid Sequence↗