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J Pastor

Publications and source records attributed to J Pastor.

At least 19 recordsLinked to original sources
PubMed2007

[Extracorporeal shock-wave lithotripsy induced ultrastructural changes to the renal parenchyma under aspirin use. Electron microscopic findings in the rat kidney].

BACKGROUND: The risk of hemorrhagic complications after extracorporeal shock-wave lithotripsy (ESWL) increases in patients with aspirin intake, but the hematoma-inducing mechanism has not been understood completely at the ultrastructural level. METHODS: The effect off shock-waves on the kidneys of male Wistar-rats (n=24) was investigated in an experimental setting using a special ESWL device. Ultrastructural examination was performed by light-, transmission electron- and scanning electron microscopy. RESULTS: Shock-wave induced tissue damage appeared in all kidneys independently of aspirin intake. Endothelial detachment, lethal cell injury, gaps and mechanical disruption of the glomerular basement membrane were regularly found. After 1 week, repair processes were completed with evidence of permanent fibrosis in some cases. CONCLUSIONS: ESWL can induce modest as well as fatal damage to renal tissue cells. Therefore, after an ESWL-induced hematoma a second ESWL should not be performed within 1 week of the first treatment.

Animals↗
PubMed2006

A role for glutamate and glia in the fast network oscillations preceding spreading depression.

The mechanism of the propagation of spreading depression is unclear. Classical theories proposed a self-maintained cycle fed by elevated potassium and/or glutamate in the extracellular space. Earlier we found in vivo a characteristic oscillatory field activity that is synchronous in a strip of tissue ahead of the oncoming wave of neuron depolarization and that occurs before the extracellular potassium level begins to rise [Herreras O, Largo C, Ibarz JM, Somjen GG, Marrín del Río R (1994) Role of neuronal synchronizing mechanisms in the propagation of spreading depression in the in vivo hippocampus. J Neurosci 14:7087-7098]. We investigated here the possible participation of glutamate and the role of glia in the prodromal field oscillations using extra and intracellular recordings and pharmacological manipulations in rat hippocampal slices. As earlier shown in vivo, field oscillations propagated ahead of the negative potential shift covering distances of up to 1 mm. The oscillatory prodromals were initially subthreshold but then each wave became crowned by a population spike. The frequency of the oscillatory prodromals was variable among slices (80-115 Hz), but constant in individual slices. The blockade of ionotropic glutamate receptors decreased the frequency of prodromal oscillations, retarded spreading depression propagation, and shortened the duration of depolarization. Blocking the glutamate membrane transport increased the oscillatory frequency. The selective metabolic poisoning of astrocytes led to gradual disorganization of prodromal oscillations whose frequency first increased and then decreased. Also, the amplitude of the population spikes within the burst diminished as individual cells fired fewer action potentials, although still phase-locked with population spikes. The effects of glial metabolic impairment were observed within the period when neuron electrical properties were still normal, and were blocked by glutamate receptor antagonists. These data suggest that glutamate released from glial cells and possibly also from neurons has a role in the generation of oscillations and neuron firing synchronization that precede the spreading depression-related depolarization, but additional mechanisms are required to fully explain the onset and propagation of spreading depression.

Animals↗
PubMed2006

Evaluation of single and double centrifugation tube methods for concentrating equine platelets.

The aim of this study was to evaluate single and double centrifugation tube methods for concentrating equine platelets. Whole blood samples were collected from clinically normal horses and processed by use of single and double centrifugation tube methods to obtain four platelet concentrates (PCs): PC-A, PC-B, PC-C, and PC-D, which were analyzed using a flow cytometry hematology system for hemogram and additional platelet parameters (mean platelet volume, platelet distribution width, mean platelet component concentration, mean platelet component distribution width). Concentrations of transforming growth factor beta 1 (TGF-beta(1)) were determined in all the samples. Platelet concentrations for PC-A, PC-B, PC-C, and PC-D were 45%, 44%, 71%, and 21% higher, respectively, compared to the same values for citrated whole blood samples. TGF-beta(1) concentrations for PC-A, PC-B, PC-C, and PC-D were 38%, 44%, 44%, and 37% higher, respectively, compared to citrated whole blood sample values. In conclusion, the single and double centrifugation tube methods are reliable methods for concentrating equine platelets and for obtaining potentially therapeutic TGF-beta(1) levels.

Animals↗
PubMed2005

Assessment of a platelet function analyser in horses: reference range and influence of a platelet aggregation inhibitor.

The objective of this study was to assess whether a new human platelet function analyser (the PFA-100) could be used to evaluate platelet function in horses and detect acetylsalicylic acid (ASA)-induced platelet dysfunctions. Citrated blood samples from 40 healthy horses were processed to obtain reference values for closure time (CT) using cartridges with collagen-ADP (CT-ADP) and collagen-epinephrine (CT-EPI) as platelet agonists. In addition, CT-ADP and CT-EPI were also measured before and 24 h after oral ASA administration in another 12 healthy horses. The sensitivity and specificity of the test were also determined. In normal horses, means+/-SD value for CT-ADP was 85.1+/-13.1 s (median, 82 s), and CT-EPI ranged from 158 to >300 s (median 291 s). Calculated reference ranges were 60.5-115.9 s and 158.5->300 s for CT-ADP and CT-EPI, respectively. Administration of ASA significantly (P<0.001) prolonged CT-ADP values from 91.0+/-13 to 113.5+/-14.4 s, and CT-EPI values were also significantly (P<0.008) prolonged after ASA administration. Sensitivity and specificity results for ADP cartridges showed that a prolonged CT value would be highly suggestive of a platelet aggregation inhibition. In conclusion, ADP cartridges can be used in horses to assess primary haemostasis and may be a valuable test for the detection of platelet aggregation inhibition.

Animals↗
PubMed2005

[T2N1M0 non-small cell lung cancer: surgery and prognostic factors].

OBJECTIVE: To determine the prognostic factors for the survival in a group of patients operated on for a non-small cell lung cancer classified as T2N1M0. PATIENTS AND METHODS: Two hundred sixteen patients treated exclusively with surgery were studied. Kaplan-Meier survival and Cox multivariable regression analyses were used. RESULTS: The overall survival rate was 39.8% at 5 years and 29.9% at 10 years. Sex, age, presence or absence of symptoms, type of resection, number, and location of affected lymph nodes had no effect on survival. Tumor size (P=.04) and histologic type (P=.03) did significantly affect prognosis. Both variables entered into the Cox multivariable regression model. CONCLUSIONS: Patients operated on for non-small cell lung cancer classified as T2N1M0 have an overall probability of 5-year survival of approximately 40%. However, the prognosis for this group of patients is heterogeneous: in our study it was affected by the histologic type (45.5% for squamous cell and 25% for non-squamous cell cancers) and tumor size (53% for tumors with a diameter of 5 cm).

Adult↗
PubMed2005

[Use of blood products in patients treated surgically for stage I non-small cell lung cancer].

OBJECTIVE: Retrospective study on the relation between the use of blood products and survival rates in patients treated surgically for stage I non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: The study included 856 patients who underwent surgical resection from 1969 to 2000 for stage I NSCLC, classified histologically according to the current guidelines of the Spanish Society of Pulmonary and Thoracic Surgery (SEPAR). Patients who died in the postoperative period were excluded from the study. A series of clinicopathological variables were recorded, including the perioperative use or not of blood products. Descriptive, univariate, and multivariate statistical analyses were performed. Follow up concluded in December of 2003. RESULTS: One hundred twenty-five patients (14.6%) underwent a perioperative transfusion. A significant association was found between the use of blood products and tumor size (P<.001), pneumectomy (P<.001), and cell type (P<.05). The respective 2, 5, and 10-year survival rates were 78%, 63%, and 54% for the nontransfusion group, and 73%, 59%, and 46% for the transfusion group. Both survival curves were compared and no significant differences were found (P=.23). Multivariate regression analysis included tumor size, patient age, and histologic cell type (squamous cell carcinoma or not); no relation between transfusion and survival was found. CONCLUSIONS: In our series, we found no difference in survival rates for patients with stage I NSCLC after perioperative blood transfusion.

Aged↗
PubMed2005

[Lung transplantation in cystic fibrosis: perioperative mortality].

OBJECTIVE: To determine the incidence and causes of perioperative mortality following lung transplant for cystic fibrosis. PATIENTS AND METHODS: We analyzed the cases of 57 patients. Fifty-five patients received double lung transplants, 1 received a heart-double lung transplant, and 1 received a combined double lung and liver transplant. Information related to the organ donor, recipient, lung graft, and early postoperative period was gathered. Perioperative mortality was defined as death resulting from anesthesia or surgery regardless of how many days had passed. The Kaplan-Meier method was used to analyze survival. A Cox logistic regression model was used to determine variables affecting mortality. RESULTS: Survival was 83.7% at 1 year after transplantation, 77.3% at 2 years, and 66.9% at 5 years. Five (8.7%) patients died as a result of anesthesia or surgery. A ratio of PaO2 to inspired oxygen fraction (FiO2) less than 200 mm Hg in the early postoperative period was observed in 8 (14%) patients. Primary graft failure occurred in 4 patients, due to pneumonia in 2 and to biventricular dysfunction in 2. Three of those patients died. Two patients with PaO2/FiO2 greater than 200 mm Hg died after surgery, one from septic shock due to Pseudomonas cepacia and the other from massive cerebral infarction. PaO2/FiO2 upon admission to the recovery care unit was the only variable significantly associated with perioperative mortality in the logistic regression model (P=.0034). CONCLUSIONS: The only factor significantly related to perioperative mortality in patients receiving transplants for cystic fibrosis was PaO2/FiO2 upon admission to the recovery unit.

Adolescent↗
PubMed2005

[Non-small cell bronchogenic cancer in stage IA: mortality patterns after surgery].

OBJECTIVE: To determine the causes of death in patients treated surgically for nonsmall cell lung cancer (NSCLC) in stage IA and to evaluate the impact on survival of not performing systematic lymph node dissection and of the number of nodes resected. PATIENTS AND METHODS: The study sample consisted of 156 patients operated on for NSCLC and classified in stage IA according to TNM staging. Only palpable or visible lymph nodes were dissected. Kaplan-Meier survival curves were compared using a log-rank test. RESULTS: At the end of the study, 85 (54.5%) patients had died, 67 (42.9%) were alive, and 4 (2.5%) were lost to follow up. Twenty-three (14.7%) died from a recurrence of NSCLC: 2 with local tumors (1.2%), 2 with mediastinal node involvement (1.2%), and 19 (12.1%) with distant metastasis. The cause of death was unrelated to NSCLC in 62 (39.7%) cases: 33 (21.1%) had a new tumor, 18 of which were bronchogenic, and 29 (18.5%) had nonmalignant disease. The 5-year survival rate was 81.4%. The rate was 88.9% among patients from whom no lymph nodes were excised and 79.9% among those with node excision, although the difference was not statistically significant (P=.4073). CONCLUSIONS: Our experience suggests that neither the fact of not performing systematic lymph node dissection nor the number of nodes resected has an impact on survival. A substantial number of patients died of causes unrelated to the NSCLC for which they had been treated.

Adult↗
PubMed2005

Myocarditis and generalised vasculitis associated with leishmaniosis in a dog.

A three-year-old, female bulldog was presented with bilateral uveitis, apathy, listlessness, generalised lymphadenopathy and perivulvar haematoma. The initial laboratory studies showed non-regenerative anaemia, polyclonal gammopathy and a high urine protein:creatinine ratio. Serology for leishmaniosis was positive and treatment with allopurinol and meglumine antimoniate was started. Despite treatment, the dog's clinical condition deteriorated. Signs included cutaneous ecchymosis, respiratory distress and finally cardiorespiratory arrest. Histopathological studies of postmortem tissue samples revealed a generalised vasculitis of several internal organs and severe myocarditis. Leishmania species organisms were identified in affected tissues using immunoperoxidase labelling and PCR techniques.

Animals↗
PubMed2004

Microanatomy of the dysplastic neocortex from epileptic patients.

Focal cortical dysplasia (FCD) is a pathology that is characterized by the abnormal development of the neocortex. Indeed, a wide range of abnormalities in the cortical mantle have been associated with this pathology, including cytoarchitectonic alterations and the presence of dysmorphic neurons, balloon cells and ectopic neurons in the white matter. FCD is commonly associated with epilepsy, and hence we have studied the ultrastructure of cortical tissue resected from three subjects with intractable epilepsy secondary to cortical dysplasia to identify possible alterations in synaptic circuitry, using correlative light and electron microscopic methods. While the balloon cells found in this tissue do not appear to receive synaptic contacts, the ectopic neurons in the white matter were abnormally large and were surrounded by hypertrophic basket formations immunoreactive for the calcium-binding protein parvalbumin. Furthermore, these basket formations formed symmetrical (inhibitory) synapses with both the somata and the proximal portion of the dendrites of these giant ectopic neurons. A quantitative analysis revealed that in the dysplastic tissue, the density of excitatory and inhibitory synapses was different from that of the normal adjacent cortex. Both increases and decreases in synaptic density were observed, as well as changes in the proportion of excitatory and inhibitory synapses. However, we could not establish a common pattern of changes, either in the same patients or between different patients. These results suggest that cortical dysplasia leads to multiple changes in excitatory and inhibitory synaptic circuits. We discuss the possible relationship between these alterations and epilepsy, bearing in mind the possible limitations that preclude the extrapolation of the results to the whole population of epileptic patients with dysplastic neocortex.

Adult↗
PubMed2004

Management of leishmanial osteolytic lesions in a hypothyroid dog by partial tarsal arthrodesis.

A five-year-old male boxer, previously diagnosed with leishmaniasis and hypothyroidism, had gradually become unable to bear weight on its left hindlimb. Physical examination revealed a left popliteal lymphadenopathy, mild crepitus, and severe swelling of the left tarsal joint, a radiographic examination of which revealed severe bone destruction of the talus and a periosteal reaction of the calcaneus. Laboratory findings and serological tests suggested an active leishmanial infection, and a Leishmania species was identified by direct cytology of a sample from the osteolytic area and by indirect immunohistochemistry of a bone biopsy. The dog's condition improved when it was treated with meglumine antimonate and allopurinol. Because of the large osteolytic area and the increased use of the affected leg, a partial tarsal arthrodesis was performed to prevent a fracture. Five months after the surgery, the osteolytic area had healed completely and the calcaneus periosteal reaction had disappeared.

Allopurinol↗
PubMed2004

Comparative haematology and blood chemistry of endangered lizards (Gallotia species) in the Canary Islands.

Blood samples were taken from the ventral coccygeal vein of 15 El Hierro giant lizards (Gallotia simonyi) (seven females and eight males), six La Gomera giant lizards (Gallotia bravoana) (four males and two females) and four Tenerife giant lizards (Gallotia intermedia) (two males and two females), and 31 blood parameters were measured. Among the haematological parameters there were significant differences between the three species in heterophils, azurophils and lymphocytes, but no significant differences in red blood cell count, white blood cell count, haemoglobin, packed-cell volume, monocytes, eosinophils and basophils. In terms of blood chemistry there were significant differences between the three species in cholesterol, triglycerides, glucose, sodium, chloride, urea, uric acid, total proteins, prealbumin, albumin and gamma globulins, but no significant differences in calcium, potassium, aspartate aminotransferase, alanine aminotransferase, creatine kinase, bile acids, alpha-1 and alpha-2 globulins and beta globulins.

Animals↗
PubMed2004

Amino acids composition of Teucrium nutlet proteins and their systematic significance.

BACKGROUND AND AIMS: Plant species are considered as a good source of dietary proteins, although the nutritional quality of proteins depends on their amino acid composition. In this work the protein content and amino acid composition of nutlets of 21 Teucrium taxa (Lamiaceae) from Spain were analysed and their nutritional quality was compared with the minimum values established by the Food and Agriculture Organization of the United Nations (FAO). In addition, the amino acid composition was evaluated as a chemical character to clarify the taxonomic complexity in this genus. METHODS: Amino acid content of nutlets was determined after derivatization with diethyl ethoxymethylenemalonate by high-performance liquid chromatography. Previously, nutlets samples were hydrolysed and incubated in an oven at 110 degrees C for 24 h. KEY RESULTS: The protein content was variable, ranging from 6.4 % in T. dunense to 43.8 % in T. algarbiense. According to the FAO values all taxa contain satisfactory amounts of leucine, threonine and valine and are deficient in lysine. The similarity analysis of Teucrium taxa using amino acid composition data did not clearly reflect the infrageneric classification of this genus. CONCLUSIONS: Annual species, such as T. spinosum, T. aristatum and T. resupinatum showed a better balanced amino acid composition. The dendrogram partly matched with the karyological complexity of Teucrium. No correlation between amino acid composition and habitat has been observed, showing that Teucrium nutlet amino acid composition may not be strongly influenced by the environment.

Amino Acids↗
PubMed2004

Micromorphological studies on seeds of orobanche species from the iberian peninsula and the balearic islands, and their systematic significance.

BACKGROUND AND AIMS: Previous research has made clear the intrinsic taxonomic difficulties in identifying species in the genus Orobanche. The aim of this study, therefore, was to investigate the systematic utility of seed characteristics. METHODS: Light and scanning electron microscopy was used to examine the seeds of 33 taxa of Orobanche from the Iberian Peninsula and the Balearic Islands. KEY RESULTS: Characters such as size, shape and ornamentation of the seeds were not found to be very useful in differentiation of taxa; however, other characters of the epidermal seed coat cells proved to be very helpful in this respect. Ornamentation of the periclinal walls could be used to discriminate four morphological types. Other features related to the anticlinal walls of the cells, such as thickness, presence/absence of a narrow trough, or relative depth, all contributed to the characterization of a large number of species. CONCLUSIONS: The usefulness of micromorphological studies on seeds of Orobanche in relation to differentiating taxa is demonstrated, and a key is provided to distinguish species or groups of species.

Cell Size↗
PubMed2004

[The natural history of sperm cleareance after vasectomy].

OBJECTIVE: To study the time required to obtain a negative sperm analysis after vasectomy. MATERIAL AND METHODS: We reviewed 239 consecutive vasectomies performed between september 1998 and september 1999. All of them were done in an ambulatory basis. Follow up interval was 41-853 days (mean 144, median 104). The first semen analysis was requested between 1 and 6 months after the surgical procedure. If the sample still showed spermatozoa, then a new one was requested every two months. Probability of becoming azoospermic was studied with Kaplan-Meier curves. RESULTS: Persistent spermatozoa could be found in 31 patients (13%) at the end of follow-up. Despite having a positive semen analysis, 10 patients (4.2%) discontinued medical visits. Time required to obtain a negative sperm count ranged from 58 to 362 days (mean 133, median 99). The probability of being azoospermic 200 and 260 days after vasectomy was 80-90% respectively. A total of 328 semen analysis were requested (range 1-4, mean 1.37, median 1) CONCLUSIONS: A minimum of 200 days (6.6 months) are needed to clear all the spermatozoa in semen after vasectomy in 80% of our patients. Requesting the first semen sample 7 months after vasectomy is cost-effective, reducing unnecesary medical visits and increasing the rentability of this test.

Humans↗
PubMed2004

[Stage I nonsmall cell lung cancer up to 3 cm in diameter. Prognostic factors].

OBJECTIVE: To assess the prognostic value of a series of clinicopathological variables in stage I nonsmall cell lung cancer, for tumors up to 3 cm in diameter. PATIENTS AND METHOD: The study included 271 patients. Survival was analyzed with the Kaplan-Meier method. The Cox model was used for multivariate analysis. RESULTS: Five- and ten-year survival were 78.63% and 67.59%, respectively. Survival did not significantly depend on sex, age, extent of resection, histology, visceral pleural invasion, level of bronchial invasion or T1 versus T2. The decade in which resection was performed did affect survival (P=.0037). Five-year survival was 58% for operations between 1970 and 1980, 77% for operations between 1981 and 1990, and 84% for operations between 1991 and 2000. Tumor size also affected survival (P=.0046), which was 86% for patients with tumors of less than or equal to 2 cm in diameter and 73% for those with tumors of more than 2 cm in diameter. In the multivariate analysis both variables entered into regression, remaining predictive of survival. CONCLUSION: We found evidence for a prognostic stage migration (Will Rogers phenomenon) according to the decade in which resection was performed and that tumor size affected survival in our population. Finally, the current system of TNM staging fails in conforming groups of patients with a homogenous prognosis.

Adult↗