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J Piquer

Publications and source records attributed to J Piquer.

At least 19 recordsLinked to original sources
PubMed2006

MRS as endogenous molecular imaging for brain and prostate tumors: FP6 project "eTUMOR".

Molecular imaging has become during the last years in an important tool for supporting cancer diagnosis and prognosis. PET and SPECT are the most common molecular imaging techniques, although very promising and specific biological molecular agent contrast for CT and MRI are being recently developed. However, the above imaging techniques require exogenous contrast agents and usually a sole molecular image can be obtained at once. On the contrary, in vivo magnetic resonance spectroscopy (MRS), in particular 1H MRS can simultaneously provide several molecular images using endogenous metabolites. In addition to biochemical spatial information from molecular imaging spectroscopy, MRS can also provide average metabolite profile of the selected affected tissue region. Initially MRS, especially 1H MRS, was extensively applied to complete and improve the diagnosis and prognosis of central nervous system (CNS) pathologies, in particular brain tumors. However, during the last years the MRS applications have been extent to the diagnosis of different very common cancer types such as breast, prostate, colon carcinoma, and ovarian, among others. Likewise, MRS has been also used for lymph node assessment. In this contribution, the added value of MRS for the diagnosis, prognosis, and treatment selection of two different, important types of cancer: (1) brain tumors and (2) prostate, will be presented and discussed. Brain tumors are the leading cause of death in children under 15, and although in adults, brain cancers are proportionately less common than other cancers, it is a devastating disease with high mortality. There is a great need to increase our understanding of brain tumor biology to improve diagnosis and to develop new treatments. 1H MRS is currently the only noninvasive method that can be used to investigate molecular profile of brain tumors and also provide molecular images, more than six in one acquisition, of the distribution of chemicals in a tumor, which are also generally heterogeneous. A summary of the applications of 1H MRS to the in vivo diagnosis and prognosis of brain tumors will be presented. In addition, examples of metabolite limits, infiltration and high cellularity location for neurosurgery applications by MRS molecular images will be shown. Likewise, new ex vivo methods of studying the detailed biochemistry of tumor biopsies as metabolomic (high resolution magic angle spinning [HR-MAS]) and transcriptomic (DNA microarrays) will be discussed as complementary to in vivo MRS (FP6 European project eTUMOR). A preliminary comparison between molecular images from PET and 1H MRS will be also presented. Finally, the application of 1H MRS to the improvement of prostate diagnosis and prognosis, the second leading cause of cancer death, will also discussed, with particular attention to the location cancer contribution from MRS molecular images.

Brain Neoplasms↗
PubMed2006

Systemic movement of Agrobacterium tumefaciens in several plant species.

AIMS: The systemic movement of Agrobacterium spp. inside plants of different species was studied to determine the most valuable diagnostic methodology for their detection. METHODS AND RESULTS: Pathogenic agrobacteria were detected by isolation and PCR in tissue away from primary tumours in tomato plants grown in the presence of Agrobacterium spp. Moreover, this bacterium was also able to induce secondary tumours beyond the inoculation site. In addition, the capacity of agrobacteria to translocate and induce secondary tumours was analysed in rose, grapevine, chrysanthemum, cherry and peach x almond hybrid GF677. No differences among strains of Agrobacterium spp. were detected in secondary tumour development, although some of them induced a significantly higher number of primary tumours in some species. Movement of inoculated pathogenic cells of four strains was also demonstrated in symptomless portions of the plant stems by isolation and PCR. Finally, pathogenic agrobacteria were detected in root, crown and stem portions of naturally infected walnuts. In all assays, PCR was the most efficient technique for detecting the movement of Agrobacterium spp. within the plants. CONCLUSIONS: Migration of agrobacteria inside plants is a complex phenomenon and more extensive than previously reported. Therefore, efficient and sensitive detection methods such as PCR must be used to select clean plants to avoid latent infections of Agrobacterium spp. SIGNIFICANCE AND IMPACT OF THE STUDY: The results show that migration of Agrobacterium spp. could be relatively frequent in several cultivated fruit trees, and systemic infections should be taken into account when designing strategies for controlling crown gall disease.

Agrobacterium tumefaciens↗
PubMed1998

[Petrous bone approach for the surgery of petroclival meningiomas].

Four patients, 3 woman and 1 man, with giant petroclival meningiomata are presented. In all cases the tumor size exceed 44 mm in its greater diametre. Main clinical symptoms were endocranial hypertension and cranial nerves deficit. A modified transcochlear approach in two stages was used. A total petrosectomy was performed, using the petrosygmoidal via for opening the dura. Transversus and sygmoid sinus were spared. Total removal was achieved in 2 cases, subtotal and partly in each of the other 2. No operative mortality occurred (hospital exitus) and neurologic morbility related to V-VI-VII and VIII cranial nerves and 1 hemyparesia was recorded. The AA. explain and comment the fundamentals of the followed procedure and compare, as well, the own outcomes with those reported by more classic alternatives. Finally, the conclusion is drawn out that retroclival meningiomata are conditions treatable, although always are difficulty approached and demand meticulous microsurgical techniques.

Cranial Fossa, Posterior↗
PubMed1997

Preoperative embolization of solid cervicomedullary junction hemangioblastomas: report of two cases.

Solid cervicomedullary haemangioblastomas represent a small but technically challenging subset of posterior fossa haemangioblastomas because of their site, high vascularity and tendency to bleed. We present our experience with preoperative embolisation of two solid cervicomedullary haemangioblastomas. In both cases the main feeding artery was the posterior inferior cerebellar artery. Arterial pedicles were catheterised with a microcatheter. The embolic material was small particles (150-250 microm) of polyvinyl alcohol. The result was almost complete preoperative obliteration of the vessels of the tumours. The procedure was well tolerated and facilitated easier bloodless, successful resection in both cases, 24 h after embolisation.

Adult↗
PubMed1997

Delayed extradural hematoma after mild head injury: report of three cases.

BACKGROUND: Extradural hematoma has been classically considered to be an acute complication of head injury whose maximum development takes place in the minutes following trauma. Delayed extradural hematoma (DEH) is defined on the basis of an exclusively radiologic criterion: epidural hematoma that is not present in the first neuroradiologic examination made after trauma but that appears in sequential neuroradiologic examinations during patient evolution. This is an infrequent complication that usually appears in hypotensive multiple trauma patients or is related to severe head injury with other intracranial lesions. CASE DESCRIPTION: We present three cases of DEH after mild head injury (GCS > 12) without associated intracranial or traumatic systemic lesions. Therefore, those usually considered to be "protective mechanisms" responsible for delayed development of an extradural hematoma were absent in our three patients. Diagnosis was attained by means of repetition of cranial computed tomography (CT) scan after neurologic impairment was noted. Surgical evacuation of DEH was immediately performed after diagnosis. Postoperative outcome was favorable in two patients who suffered DEH in the supratentorial compartment. One patient who presented a posterior fossa DEH died 3 days after surgery. CONCLUSIONS: Early diagnosis and immediate treatment have proved to be essential for improving the prognosis of patients affected by DEH. Hospital admission under neurologic observation is recommended for patients who have sustained mild head injury associated with those factors that are related to the development of DEH, including GCS score under 15 or the detection of a skull fracture. Normality of a CT scan does not rule out subsequent appearance of delayed traumatic lesions.

Adolescent↗
PubMed1996

Surgical treatment of epidermoid cysts of the cerebellopontine angle.

A total of 40 patients with epidermoid cysts of the cerebellopontine angle (CPA) underwent surgery between 1980 and 1993. Total resection was achieved in 30 cases (75%); in 10 cases (25%) parts of the cyst capsule were left because they adhered to the brainstem and vascular structures of the CPA. One patient with very large bilateral epidermoid cysts, who underwent complete bilateral resection in one stage, died of pulmonary aspiration and infection. As of their latest clinical and radiological follow-up examinations (mean 5.7 years), 93% of the patients are able to lead useful lives. Three cases of cyst regrowth have been observed thus far. Modern radiological tools and microsurgery techniques have considerably improved the completeness of cyst resection and reduced postoperative mortality and morbidity rates; however, there still are some cases in which complete resection is impossible without producing severe neurological deficits.

Adult↗
PubMed1992

Dietary effects on stunting syndrome in poults.

Experiments were done to determine the effect of feeding diets of different ingredient composition to poults experimentally infected with stunting syndrome (SS) at 1 day of age. In Experiment 1, feeding a complex diet (CPX) containing fish meal and sunflower meal as the main protein sources eliminated the adverse effects of SS inoculation on performance traits as compared with SS effects on poults fed a corn and soybean meal (CS) diet. In Experiments 2 and 3, the effects of SS were more severe than in Experiment 1. In these experiments, the CPX diet only partly overcame the adverse effects of SS on performance (i.e., in Experiment 2, growth depressions from 2 to 5 days of age were 90.3 and 59.6% in SS-inoculated poults fed the CS and CPX diets, respectively, as compared with uninoculated, control poults fed the same diets). Properties of the CPX diet that made it effective in reducing the severity of SS were not evident from the results of Experiment 3. Replacing soybean meal with soy protein or canola meal was ineffective as compared with the use of a mixture of sunflower meal, fish meal, meat and bone meal, and corn gluten meal.

Animal Feed↗
PubMed1992

Responses of turkey poults to virginiamycin as influenced by litter condition and experimentally induced stunting syndrome.

Two experiments were conducted to evaluate the effect of virginiamycin (VM, 22 mg/kg of diet) on performance of uninfected (CON) turkey poults and those infected (INO) with stunting syndrome and reared on used woodshavings (Experiment 1) or on clean or used woodshavings (Experiment 2). Virginiamycin improved BW (P less than .001) and feed efficiency (FE) (P less than .05) from 1 to 29 days of age, irrespective of type of litter or disease condition. The increase in BW induced by VM, however, was greatest when poults were kept on used litter, resulting in significant (P less than .05) VM by litter interaction. Induced stunting syndrome depressed BW (P less than .01) to 29 days of age and impaired FE from 1 to 9 days of age (P less than .05) and from 5 to 9 days of age (P less than .01) in Experiments 1 and 2, respectively. Virginiamycin did not prevent early adverse effects of INO on BW and FE, but facilitated notable recovery of INO poults relative to INO poults not fed VM. Virginiamycin increased specific activities of maltase and sucrase of the jejunum of CON poults in Experiments 1 and 2; in Experiment 2, this VM effect was evident irrespective of type of litter. Maltase-specific activity and sucrase were reduced by INO (P less than or equal to .05 and P less than or equal to .01 in Experiments 1 and 2, respectively) and VM did not modify this effect. The maltase and sucrase data suggest that VM improved BW and FE of CON poults, in part, by helping to maintain digestive and absorptive functions of the small intestine during the early growth period, but, in the instance of INO poults, VM was not effective in this regard.

Animals↗
PubMed1991

Correlations of female steroid hormone receptors with histologic features in meningiomas.

A series of 39 samples were obtained from meningiomas in 28 patients in order to investigate the relationships of the oestrogen receptor (OER) and progesterone receptor (PR) with the tumoural subtype and some histological features. Twenty-one samples were positive (greater than 10 fmole/mg protein), 7 were OER-PR-negative, and 1 was positive in both receptors. Twenty-two samples were considered as syncitial, 7 transitional, 7 fibroblastic and 3 angioblastic. The histological subtype was not found to be significantly related to the presence or absence of PR. Relations were not observed between the progestin receptor and the following histological parameters: cellular pattern, cell density, nuclear polymorphism, mitosis, lymphoplasmacellular infiltrates, degree of vascularization, psammoma bodies and interstitial fibrosis. Only the presence of intratumoural necrosis was significantly related with a low PR levels. However, progesterone binding activity was lower in tumours with numerous psammomas, fibroblastic cell pattern and interstitial fibrosis. The clinical and biological significance of these results is discussed.

Adult↗
PubMed1987

Long-term results of percutaneous gasserian ganglion lesions.

Percutaneous radiofrequency lesion of the Gasserian ganglion was performed between 1974 and 1984 in ninety-eight patients for the relief of trigeminal neuralgia. The average follow-up period was 4.5 years. Age, sex, and duration of illness were unrelated to outcome. Satisfactory analgesia was achieved in 68 patients. Thirty-one percent had return of pain (30 cases). Recurrent neuralgia occurred most frequently during first postoperative year (46%). Patients with marked sensory deficits had a reduced risk of recurrence. Postoperative complications included: reduced or absent corneal reflex (18 cases), corneal keratitis (3 cases) and anesthesia dolorosa (2 cases).

Adult↗
PubMedDate not supplied

[Meningiomas: immunohistochemical analysis of 26 cases].

We have analyzed, with immunohistochemical staining techniques 26 meningiomas of CNS. Vimentin intermediate filaments was present in all cases in the cytoplasm of tumoral cells. Single epithelium cytokeratin was positive in only 19% cases, same that was obtained with S-100 protein. Whereas 69% of cases expressed epithelial membrane antigen. No case was stained positively with Actin, Desmin and GFAP. The results obtained for others authors are analyzed.

Antigens, Neoplasm↗
PubMedDate not supplied

[Ag-NOR in meningiomas. Clinical and morphologic study of 14 cases].

A total of 14 meningiomas were studied in this report, grouped in different subtypes. The number of NORAg of each was analyzed and quantified. This study analyzes the results obtained as opposed to different subtypes and with clinic and biologic characteristics of patients. Similarly, technical characteristics of silver impregnation method to determine nucleolar organizer regions (NORAg) and its application as a routine method were analyzed. We propose this as a fast and reliable method to analyze of neoplastic proliferative activity.

Adult↗
PubMedDate not supplied

Association of chromosome 7, chromosome 10 and EGFR gene amplification in glioblastoma multiforme.

Glioblastoma multiforme (GBM) is characterized by intratumoral heterogeneity in both histomorphological and genetic changes, displaying a wide variety of numerical chromosome aberrations, the most common of which are trisomy 7 and monosomy 10. The amplification of the epidermal growth factor receptor (EGFR) gene is the most frequently reported genetic abnormality. The associations between these parameters and their implication in the tumoral progression are poorly understood. We performed simultaneous fluorescence in situ hybridization (FISH) with centromeric DNA probes for chromosomes 7 and 10 in smear preparations, and EGFR gene amplification by PCR from 25 cases of GBM. Trisomy/ polysomy for chromosome 7 was present in 76% of cases and monosomy 10 in 68%. Both alterations were associated in 56% of cases. The EGFR gene was amplified in 52% of tumors; in 44% associated with trisomy/ polysomy 7, and in 36% with monosomy 10. The three parameters were associated together in 28% of cases. Kaplan-Meier survival rate analysis demonstrated lower survival rates in patients with monosomy 10, trisomy 7, and monosomy associated with trisomy 7. The other combinations were not different in frequency in relation to survival. In the present study, trisomy/polysomy 7 and monosomy 10 have been found to be frequently associated. The combination of both anomalies is probably important in the tumorigenesis of glioblastoma. Moreover, this association is apparently independent of EGFR gene amplification, which could be a later event in this process.

Adult↗
PubMedDate not supplied

[Tumors of the choroid plexus: morphologic and immunohistochemical study].

We present a morphological and immunohistochemical study on three papillomas and one carcinoma of the choroid plexus. Clinical characteristics are analysed. Morphological criteria for malignancy are: solid histological pattern, cellular polymorphism, nuclear atypia and infiltration of nervous tissue. The immunohistochemical study shows the value of GFAP, S-100 protein, HNK-1 and Vimentin as specific markers. In the discussion we point out the differential diagnosis between these types of tumors and the metastasis from papillary carcinomas and ependymomas.

Adult↗
PubMedDate not supplied

[Differential immunohistochemical characteristics of meningiomas and other neoplasms of the central nervous system].

We present an immunohistochemical study of 16 meningiomas and 19 CNS tumors including gliomas, neurinomas and metastatic carcinomas, in order to establish a histopathologic differential diagnosis, using formalin-fixed and paraffin-embedded material. The antibodies analysed included vimentin, GFA-protein, cytokeratin, S-100 protein and epithelial membrane antigen. Meningiomas always express vimentin as marker, and occasionally cytokeratin and EMA. The most constant antigens demonstrated in astrocytomas were GFA-protein and vimentin, and occasionally we were able to detect S-100 protein. Neurinomas proved positive to S-100 protein, and metastases presented cytokeratin and EMA reactivity. Our results confirm the existence of diverse immunohistochemical patterns within CNS tumors, a fact that can be useful in routine differential diagnosis.

Astrocytoma↗
PubMedDate not supplied

Meningiomas: karyotypes and histological patterns.

The cytogenetic findings, based on G-banding, in six meningiomas are reported. Normal karyotypes were found in three cases and monosomy of chromosome 22 in the remaining three. In one of these three cases, a malignant meningioma, several chromosomes were lost, gonosome Y included. The possible significance of the association of chromosome alterations in meningiomas with the histology of the tumor and its biological aggressivity is discussed.

Adult↗