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J R Iglesias

Publications and source records attributed to J R Iglesias.

At least 19 recordsLinked to original sources
PubMed2006

Eight-channel ultrasonic device for non-invasive quality evaluation in packed milk.

An eight-channel ultrasonic detecting device for microbiological quality evaluation of packed liquid foods is presented in this paper. This device makes possible a non-invasive detection of the microbial growth in liquid foods with no need to open the carton-based packages where they are contained. Thermal and humidity stabilization are required inside the measuring chamber. The changes in the liquid media produced by the microorganism growth induce variations in the ultrasonic propagation parameters giving a non-invasive evidence of the developing contamination. For that purpose, the amplitude and time of flight of an ultrasonic 800kHz tone burst travelling through an UHT milk pack are analysed. Inoculated and sterile packs were tested to evaluate the performance of this new non-invasive ultrasonic microbiological quality sensor.

Animals↗
PubMed1997

Excision and anastomotic repair for urethral stricture disease: experience with 150 cases.

PURPOSE: To analyze the results of a series of end-to-end urethroplasties performed in our service from 1968 to 1995 and of the factors contributing to failure. MATERIAL AND METHODS: 150 men (mean age 35.9 years) with urethral stricture disease underwent excision of the stricture and end-to-end anastomosis; in 95 it was the first attempt at repair while in 55 it was a secondary attempt. Eighty-two patients (54.6%) had a trauma-related stricture; of them, 56 followed a pelvic ring fracture with posterior urethra distraction defect, 24 (16%) had inflammatory strictures, 26 (17.3%) iatrogenic, 9 (6%) congenital, and 9 (6%) of unknown etiology; 81 (54%) were located in the bulbous urethra, 9 (6%) in the penoscrotal junction and 2 (1.3%) in the penile urethra. Ninety-one (60.6%) of the strictures or obliterative defects measured between 1 and 3 cm, 42 (28%) less than 1 cm and only 16 (10.6%) more than 3 cm. A perineal approach was used in 138 of the cases, while combined abdominoperineal route was necessary in 12; of these, 5 were children. The follow-up has ranged from 6 to 168 months (mean 44.4). The results were classified as good, fair (some re-stricturing, not needing treatment) and poor (recurrence). RESULTS: One hundred and twenty-six (84%) good outcomes, 10 (6.6%) fair, 14 (9.3%) poor. The factors influencing success or failure were: (1) primary or secondary character of the operation; (2) etiology; (3) length, and (4) location. Postoperative early complications consisted of 2 wound infections and 2 hematomas; as late complications, 1 chordee, 2 incontinence, 7 erectile dysfunction (in previously potent patients). The 14 patients considered as failures were operated again, all successfully; in 4 of them, a repeat excision and end-to-end anastomosis was performed, elevating the final success rate of the series to 93.3%. CONCLUSION: Excision and anastomotic repair represent the optimal mode of stricture repair for single lesions located from the penoscrotal junction to the membranous part of the urethra.

Anastomosis, Surgical↗
PubMed1992

[The magnetic resonance tomography of intracranial ependymomas. Their clinical appearance and comparison with computed tomography].

The MRT and CT images of histologically confirmed intracranial ependymomas in 10 patients have been compared. All tumours were demonstrated by CT and MRT. The solid portions of the tumours showed variation in density on CT (hypodense, isodense, hyperdense, or mixed), whereas there was uniform signal intensity on MRT (T1 weighted: hypointense, T2 weighted: hyperintense). Cystic portions of the tumours (6 patients) were shown equally well by both procedures, calcifications were only shown by CT. All ependymomas were related to the ventricles. On unenhanced CT only 3 tumours were clearly delineated, whereas MRT defined all tumours satisfactorily. The significant advantage of MRT is better topographic demonstration of the tumour.

Adolescent↗
PubMed1991

Experimental CNS tumors in rats. Testing field for a computerized classification and tumor grading.

The purpose of this study was to verify the efficiency of a previously described method for the computerized histological diagnosis of experimental brain tumors (Kroh et al. 1988). 117 tumors (astrocytomas, glioblastomas, meningosarcomas, neurinomas, oligoastrocytomas and oligodendrogliomas), experimentally induced in rats, were studied. In every case the same 50 histological characteristics used for the elaboration of a computerized system for the diagnosis of experimental brain tumors in mice were analyzed. Our results demonstrate the efficiency of this diagnostic method for experimental brain tumors. Furthermore, the grade of malignancy of these tumors was also determined by using a previously described computer program.

Animals↗
PubMed1990

Primary leptomeningeal gliomatosis with predominant involvement of the spinal cord.

The authors report on a 43-year-old male with apparent myelomeningeal encephalitis. The most important clinical symptoms included severe lymphocytosis of the CSF, cranial nerve palsies, obstructive hydrocephalus, progressive coma, and presence of an intramedullary mass causing paraplegia. Neither CSF analysis, nor the intraoperative findings gave evidence of a neoplastic process. Regarding the paraclinical data we supposed a CNS inflammatory process, but autopsy revealed the diagnosis of an intraspinal, leptomeningeal gliomatosis.

Adult↗
PubMed1988

Histologic characterization of 41 ependymomas with the help of a personal computer.

Fourty-one ependymomas were histologically analyzed in relation to patient age and sex and tumor location. A discriminant analysis model using Bayes' formula and a personal computer were employed. Ependymomas situated in the posterior fossa had a higher incidence in children. Ependymoblastomas were all situated above the tentorium and occurred only in young children. We identified three tumor groups on the basis of common histologic characteristics: benign ependymomas, anaplastic ependymomas, and ependymoblastomas. The main features useful for the grouping were the degree of differentiation and anaplasia. Ependymomas from the cauda equina showed histologic characteristics that allowed them to be differentiated from other benign ependymomas. In each group the particular histologic characteristics, age, and location were significant in terms of diagnosis and prognosis. This method of analysis may help to more precisely define ependymomas and may provide pathologists and clinicians with a quantifiable diagnostic tool that may be of help in establishing the appropriate treatment.

Adolescent↗
PubMed1988

Computer classification of experimental brain tumors in mice.

The purpose of this study was to develop a mathematical model which would be easy to use and which could provide an objective classification of experimental brain tumors. 250 brain tumors (glioblastomas, astrocytomas, astroblastomas, oligodendrogliomas, ependymomas, fibrosarcomas and giant cell sarcomas), induced in mice, were studied. In every case the same 50 histological characteristics were analyzed. For astroblastomas, oligodendrogliomas and ependymomas the diagnosis given by the neuropathologist and that given by the computer corresponded in 100% of the cases. However, some fibrosarcomas and giant cell sarcomas were not grouped in the same diagnostic category by the computer as that assigned by the neuropathologist. Thus an overall efficiency of 94.35% was obtained. This simple and efficient system of classification allows for further statistical analyses and makes it possible to correlate the results presented by different authors, thus providing for unity in all those works concerned with experimental neurooncology.

Animals↗
PubMed1986

Histopathological diagnosis of brain tumours with the help of a computer: mathematical fundaments and practical application.

With the help of a personal computer we have subjected 1684 tumours of the central and peripheral nervous systems to a discriminant analysis to test whether the different brain tumours can be classified. By ascribing a coefficient value which belongs to a linear function to the objective criteria for each tumour these can be ordered in groups, and a classification is then possible. This has been termed discriminant analysis. Fifty histological characteristics were the criteria taken into consideration for each tumour. By using Bayes' formula with a correction for binomial distribution we obtained a correct diagnosis in 98% of the cases studied. The differential diagnosis with its percentage of probabilities is given by the computer. The mathematical fundaments are given. The valuability and precision of this method are discussed.

Brain Neoplasms↗
PubMed1986

A model of semiautomatic type-specific diagnosis of brain tumours by computed tomography: mathematical fundaments and practical application.

Applying Escudero's formula to Bayes' theorem of conditional probabilities, we have developed a mathematical model to diagnose type-specific brain tumours with great accuracy. We have transformed a multidimensional system of n characteristics on computed tomography into a linear system, making this model very easy to use and, thus, accessible to the clinician and radiologist. We tested this model in 177 brain tumours. In 86% of the cases we obtained a type-specific correct diagnosis, achieving better results than those previously reported. Suggestions are given as to how to improve this method further.

Brain Neoplasms↗
PubMed1984

Prenatal intramedullary gliofibroma. A light and electron microscope study.

A case of an unusual congenital intramedullary tumor of the spinal cord is reported. A paraplegic 11-day-old boy with hypotonia and atrophy of the abdominal and lower-extremity muscles showed a complete myelographic block between T-5 and T-8. Surgical exploration disclosed an elongated tumor mass within the spinal cord, that blended with the surrounding nervous-system tissue. Light and electron microscopy showed that the tumor was composed of intermingled well differentiated astrocytes and fibroblasts. These two cell types often were surrounded by the same basal lamina. There were no intercellular junctions. Gliofibrils were abundant, and the interstitial spaces contained abundant collagen and reticulin fibers. There were no histological signs of malignancy. We conclude that this is a case of prenatally arising gliofibroma.

Humans↗
PubMed1983

Rete mirabile of goat: in vitro effects of adrenergic stimulation.

The carotid rete of the goat, a network of small arteries, is placed in the pathway of the main arteries which supply the brain. This structure lies within the cavernous sinus on each side of the pituitary. The presence of a carotid rete in many mammals has led to frequent speculations about its physiological function. The present study was designed to examine comparatively the responsiveness of goat retial and cerebral arteries to direct or indirect adrenergic stimulation. The contractile response of isolated retial arteries (150-500 micron in external diameter) to norepinephrine (10(-8) - 10(-4)M), field electrical stimulation (2-16 c/s), and tyramine (10(-6) - 10(-3) M) was negligible. In contrast, cerebral arteries of 300-500 micron in external diameter exhibited dose- or frequency-dependent contractions qualitatively similar to those previously described in larger cerebral arteries. The norepinephrine content in the walls of retial arteries was about 13% of that measured in cerebral arteries. These results suggest that the role of the carotid rete in the regulation of resistance to blood flow during adrenergic stimulation is negligible or nonexistent.

Adrenergic Fibers↗
PubMed1981

Intracerebral arachnoidal cyst containing choroid plexus. Case report.

A case of an intracerebral "primary" arachnoidal cyst of the left fronto-parietal region is reported. No communication with the ventricular system or with subarachnoidal space was found at the first surgical procedure. It contained genuine choroid plexus and clinically behaved as an expansive intracranial mass.

Arachnoid↗