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V Calvo

Publications and source records attributed to V Calvo.

At least 19 recordsLinked to original sources
PubMed2005

Urgent lung transplantation in Spain.

BACKGROUND: Lung donors are scarce and lung transplantation resources are limited. Because urgent lung transplantation (ULT) is assumed to yield poor results, its use is controversial. We assessed the outcome of patients who received ULT seeking to determine effectiveness and risk factors. PATIENTS AND METHOD: We collected data from every ULT performed in Spain during 5 years (1998-2002). The survival of patients was studied using Kaplan-Meier, Cox regression, and chi-square statistical analyses. We compared outcomes and perioperative mortality (over 30 days) for ULT procedures, analyzing the influence of certain variables (age, type of transplant, diagnosis, indication, and time on waiting list). RESULTS: Among 109 patients proposed for the procedure, 73 ULT were performed during the period. The most frequent indications were pulmonary fibrosis (19 cases) and cystic fibrosis (19 cases), showing the worst and the better survival rates, respectively. The bad prognosis, determined mainly by per operative mortality rate (35.62%), was significantly affected by age (worse for patients older than 40 years) and type of LT (single worse than double; P < .05). A longer time waiting for ULT also showed a worse prognosis (P < .005). CONCLUSIONS: Long-term survival after ULT shows that the procedure is effective and efficient for a select group of patients, despite the high per operative risk. ULT should be reserved for younger patients. It also requires performance in a short period (just a few days), initially rejecting a single lung transplant, provided that the patient is adequately monitored.

Humans↗
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↗
PubMed2004

Two-dimensional electron-hole liquid in single Si quantum wells with large electronic and dielectric confinement.

We report a luminescence study of the electronic properties of the 2D electron-hole liquid in crystalline Si quantum wells with SiO2 dielectric barriers. The Fermi-Dirac condensation of e-h pairs into a metallic liquid is strongly enhanced by spatial localization. We present experimental evidence for the formation of liquid nanodroplets, with size increasing with e-h pair density. The quantum confined regime is observed for well width below 15 nm. The data are analyzed in a confinement model that takes account of the band-gap renormalization by 2D many-body effects and the increase of the Coulomb interactions due to the dielectric mismatch between the Si well and the SiO2 barriers.

Journal Article↗
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↗
PubMed2003

Cardiopulmonary transplantation: experience of a lung transplant group.

Cardiopulmonary transplantation (CPT) is indicated for patients eligible for heart transplantation (HT) or lung transplantation (LT) who have severe concomitant lung or heart disease. Only 2 groups perform CPT in Spain. We report our experience with 18 CPTs representing 8.2% and 5% compared with LT (220) and HT (362), respectively, from February 13, 1990 to October 15, 2002. The mean time on a waiting list was 138 days. The current number of surviving patients is 7 (39%), with a mean follow-up of 602 days (range, 3 to 4627 days). They all remain asymptomatic with normal respiratory function in 4 patients. No cardiac graft rejection has been detected. Two patients experienced sustained gastroparesis during the first year with spontaneous resolution. Death occurred within the first 3 months in 9 patients. These outcomes contrast with the early mortality associated with LT and HT in our series, namely 10.6% and 11%, respectively. The different causes of death were as follows: sepsis and multiorgan failure in 5 patients, hemorrhagic shock in 3 patients, and suture dehiscence and fungal aortic perforation in 1 patient. Late mortalities were recorded in 2 cases. Overall patient survival in our series is lower than that reported by the International Registry (IR), with an early mortality rate of 50% (30% IR). Nevertheless, our survival rate at 10 years after transplantation is 30% (26% IR). We conclude that CPT should be considered despite the greater early morbidity and mortality.

Adolescent↗
PubMed2003

[Emergency lung transplantation].

INTRODUCTION: Lung donors are scarce and lung transplantation resources limited, leading to a need to look at transplants in terms of efficiency. Because emergency transplants (C-0) are assumed to yield poor results, most countries do not perform them on a regular basis. Spain, however does accept the concept of emergency lung transplantation for patients who are on waiting lists. We assess outcome for our patients who have received scheduled and emergency transplants. MATERIAL AND METHOD: The survival of patients receiving lung transplants in our service from 1992 through 2001 was studied using, Kaplan-Meier, Cox regression and chi-squared statistical analyses. We compared outcome and perioperative mortality (over 30 days) for scheduled versus C-0 procedures, analyzing the influence of certain variables (age, sex, emergency status, type of transplant, mechanical ventilation and use of extracorporeal membrane oxygenation). RESULTS: Eleven of 183 lung transplants were C-0 and 172 were scheduled. Forty-one were single-lung and 142 were double-lung transplants. Perioperative mortality was 36.4% for emergency procedures and 8.7% for scheduled procedures (p = 0.0035). Survival was significantly better for scheduled patients than for C-0 patients (p = 0.0032), although outcome was similar when perioperative mortality was not taken into account (58.16% vs. 57.14% at 5 years for scheduled and C-0 patients, respectively). CONCLUSIONS: Long-term survival after lung transplantation shows that the procedure is effective and efficient in C-0 patients, in spite of perioperative risk, provided the patient has been adequately monitored.

Adolescent↗
PubMed2002

Survival and risk model for stage IB non-small cell lung cancer.

BACKGROUND: The aim of this work is to estimate the prognostic value of a set of clinical-pathological factors in patients resected for non-small cell lung cancer (NSCLC) and classified as stage IB, in order to create a prognostic model for establishing risk groups, and to validate that model. METHODS: Among 637 patients resected and classified as stage IB, we analyzed sex, age, symptoms, location, type of resection, cell type, histology, and tumor size. The Kaplan-Meier method was used to estimate the survival. The results were compared using the log-rank test. All the significant variables from this univariable method were then included in a multivariable method of estimation of the proportional risk for survival data developed by Cox, using the variables selected, a regression model was developed for accurately predicting survival. To validate the predictive capability of the regression model, we randomly divided our patients into training and test subsets, containing 322 and 315 cases, respectively. RESULTS: The overall 5-year survival rate of the series was 60%. The cell type, the squamous or non-squamous and the tumor size showed a significant influence on survival in the univariable analysis, while, according to the Cox model, only the tumor size and the squamous or non-squamous type entered into regression. Hazard rates were calculated for each patient. The mean risk was 0.87 +/- 0.25 (range 30-1.94). The series was divided into three risk groups (low, intermediate, and high risk) according to the fitted hazard rates, using cut-off points (one standard deviation from the mean). The 5-year survival rates were 85, 59, and 44%, respectively. To validate the model, we repeated the analysis for training and test subsets. Only the tumor size had a significant influence on survival in the univariable analysis. Using the Cox model, also the tumor size entered into regression. The mean risk was 0.79 +/- 0.29 (range 0.09-2.12). Cut-off points were 0.50 and 1.08 for the low, intermediate, and high-risk groups. The 5-year survival rates were 83, 58, and 40%, respectively. We validated the regression model obtained in the training subset by demonstrating its capacity in identifying risk groups in the test subset. The 5-year survival rates were 83, 61, and 49.5% for the low, intermediate, and high-risk groups, respectively (P = 0.0104). CONCLUSIONS: Stage IB does not succeed in configuring a group of patients with a homogeneous prognosis, as there is a wide variability in a 5-year survival. The estimation of prognosis derived from a multivariable analysis can obviate the limitations of the actual staging system for NSCLC.

Adenocarcinoma↗
PubMed2002

[Single-lung transplant and primary graft failure].

OBJECTIVE: To quantify primary graft failure (PGF) and its impact on perioperative and early mortality in single-lung transplant (SLT). METHOD: We analyzed 35 SLT procedures performed using similar techniques. PGF was defined as a PaO2/FiO2 coefficient lower than 200 mmHg during the first 72 hours or ventilation assistance lasting longer than 5 days attributable to primary lung dysfunction. We defined perioperative mortality as occurring within 30 days of surgery and early mortality within 90 days. RESULTS: Twenty-five men and 10 women received lungs, 22 for pulmonary fibrosis and 13 for emphysema; the mean age was 53.26 10.77 years. Twenty right SLTs were performed and 15 left SLTs. Twenty-nine donors were men and 6 were women, with a mean age of 29.31 12.33 years. Twenty-six died from cranial trauma, 8 from stroke and 1 from a brain tumor. The mean time of intubation was 1.69 1.35 days. The mean PaO2 was 470.71 70.82 mmHg. The mean time of ischemia was 201.77 62.64 minutes. Four patients (11.42%) developed PGF and 3 died during the perioperative period. Two additional patients died within the early postoperative period. Survival was 91.4% at one month and 85.5% at three months. The cause of donor death was the only variable that influenced the development of PGF. CONCLUSION: We observed a low incidence of PGF and of perioperative and early mortality, with one and three month survival rates similar to those reported internationally.

Adolescent↗
PubMed2002

[Lung transplantation in patients in mechanical ventilation before transplantation].

Mechanical ventilation before lung transplantation has been identified as a risk factor for early death after surgery. However, several studies have reported patient series in which ventilation assistance was given preoperatively without increasing the rates of postoperative complications and death, apart from increasing time of postoperative intubation. The present retrospective analysis of the postoperative course of patients who had been mechanically ventilated before transplantation encompasses a period of 5 years in our hospital. Eight transplants (7 double- and 1 single-lung procedures) were performed. Six patients (75%) required extracorporeal oxygenation during surgery. Three patients (37.5%) died within 30 days of receiving the transplanted lung. The mean time of intubation after the operation was 10.3 days and the mean stay in the postoperative recovery and intensive care unit was 27.5 days. The most common postoperative complications were respiratory colonization (100%), with infection in 3 patients, and reimplantation injury (50%). Pretransplant mechanical ventilation was associated with high risk in the patient series we report; however, the survival rate observed suggest that such patients should be considered acceptable candidates to receive grafts if indicated.

Adolescent↗
PubMed2001

[Model of mortality risk in stage I non-small cell bronchogenic carcinoma].

OBJECTIVE: To develop and validate a mortality risk model for patients with resected stage I non-small cell bronchogenic carcinoma (NSCBC). PATIENTS AND METHOD: Tumors from 798 patients with diagnoses of NSCBC were resected and classified in stage I. The Kaplan-Meier method and Cox's proportional hazard model were used to analyze the influence of clinical and pathologic variables on survival. RESULTS: Univariate analysis revealed that age (p = 0.0461), symptoms (p = 0.0383), histology (p = 0.0489) and tumor size (p = 0.0002) and invasion (p = 0.0010) affected survival. Size (p = 0.0000) and age (p = 0.0269) were entered into multivariate analysis. Each patient's risk was estimated by applying the regression equation derived from multivariate analysis; the mean was 1.47 +/- 0.31 (range 0.68 to 2.92). The series was divided into three groups by degree of risk (low, intermediate and high), establishing the cutoff points at 1.16 and 1.78 (standard deviation of the mean). Five-year survival rates were 85%, 62% and 46%, respectively (p = 0.0000). To validate the model's predictive capacity, the series was divided randomly into two groups: the study group with 403 patients and the validation group with 395. Age (p = 0.0295), symptoms (p = 0.0396), tumor size (p = 0.0010) and invasion (p = 0.0010) affected survival in the univariate analysis. Size (p = 0.0000) and age (p = 0.0358) were entered into Cox's model. Mean risk was 1.94 +/- 0.36 (range 0.98 to 3.32). The series was divided into three risk groups, with cut-off points established at 1.58 and 2.30. Five year survival rates were 90%, 62% and 46% for the low, intermediate and high risk groups, respectively (p = 0.0000). The same model proved able to identify risk when applied to the validation group, in which five-year survival rates were 78%, 61% and 48%, respectively (p = 0.0000). CONCLUSIONS: Risk models can identify patient subgroups, potentially influenced by co-adjuvant treatment, as well as facilitate comparison of patient series.

Adult↗
PubMed2001

Vocabulary development in Italian children: a longitudinal evaluation of quantitative and qualitative aspects.

In this study vocabulary development of a sample of 42 Italian children was evaluated through monthly administration of the Italian version of the CDI. Data collection started at 1;0-1;1 for 32 children and at 1;3-1;4 for the remaining subjects and continued until children's vocabulary reached 200 words. At fixed stages of vocabulary size (50, 100 and 200 words), individual differences in percentile scores and vocabulary composition were examined. Individual growth curves were analysed in order to verify the presence of a vocabulary spurt and the type of lexical items which contributed most to rapid acceleration in vocabulary growth. Stylistic differences in vocabulary composition were examined regarding the 'referential-expressive' distinction, controlling vocabulary size. Data have shown that general trends in vocabulary development are quite similar to those obtained for other languages using CDI adaptations. Moreover, all children in this sample eventually exhibited a vocabulary spurt, even if some can be defined as 'late spurters'. The type of lexical items which are learned during the spurt depend on both infant vocabulary size and referential score. About 28% of infants in this sample were defined 'referential' when their vocabulary size was about 50 words, but the stylistic differences disappeared at the 100- and 200-word stages. Composition of vocabulary did not differ in relation to precocity in reaching different stages of vocabulary development. The only exception was that infants who reached the 50-word stage first also had a vocabulary with a lower proportion of function words.

Child Language↗
PubMed2001

Duss Fairy Tales: some data from a new evaluation form.

The purpose of this paper is to extend the research on the Duss Fairy Tales in an Italian sample. Attention has been paid, in particular, to the study of some variables identified in a newly devised schedule. The protocols were scored for four indexes: (1) the main hero of the stories, (2) number and types of characters, (3) number of emotions expressed, and (4) number of heroes' and characters' actions and behaviors. Subjects were 70 children aged 3.5 to 10.5 yr. enrolled in kindergartens and elementary schools in Italy. The relationships of scores with age and sex were also investigated. There was an increase across three age groups in the richness of stories in terms of emotions and characters' identification.

Child↗
PubMed2000

COT kinase proto-oncogene expression in T cells: implication of the JNK/SAPK signal transduction pathway in COT promoter activation.

COT/Tpl-2 proto-oncogene encodes a serine/threonine kinase implicated in cellular activation. In this study we have identified the human COT gene promoter region and three different human COT transcripts. These transcripts, with the same initiation site, display heterogeneity in their 5' untranslated regions and in their subcellular localization. Activation of Jurkat T cells with either calcium ionophore or alphaCD3 and a phorbol ester increases the levels of the different COT transcripts. Analysis of the 5' flanking region of the human COT gene reveals a unique transcription initiation site and a TATA element 20 nucleotides upstream. Transient expression of COT promoter constructs containing a reporter gene indicates that the transcriptional activity of the 5' flanking region of the COT gene is regulated by T cell-activating signals. Cotransfection of a dominant negative version of SEK-2 abolishes the inducible transcriptional activity of COT promoter, indicating that the inducible expression of the COT gene by T cell activating signals is mediated by the JNK/SAPK signal transduction pathway. All these data indicate stringent regulation of COT kinase proto-oncogene expression.

5' Untranslated Regions↗
PubMed2000

[Small-cell nonanaplastic bronchogenic carcinoma. The new stage I].

OBJECTIVE: To validate updated guidelines for stage I classification of patients with differentiated small-cell bronchogenic carcinoma. METHODS: Seven hundred seventeen tumors of differentiated small-cell bronchogenic carcinoma were resected in our hospital and given a TNM classification of stage I based on guidelines recently issued by the Spanish Society of Pneumology and Chest Surgery (SEPAR). Survival was calculated using the Kaplan-Meier method and curves were compared with a log-rank test. The Cox proportional hazards model was used to analyze multiple variables. RESULTS: One hundred forty-two cases were classified as stage IA and 575 as stage IB. Survival was significantly longer for stage IA than for stage IB (p = 0.0021). The prognosis was significantly better for stage IA patients who were asymptomatic (p = 0.0380) or who had tumors < or = 2 cm in diameter (p = 0.0431). In stage IB, histologic grade (p = 0.0104) and tumor diameter (p = 0.0002) significantly affected survival. A noteworthy finding was the 82% survival at five years in a group of 66 patients with a maximum tumor diameter of 3 cm classified as T2N0M0 due to invasion of the visceral pleura or to proximal involvement of a lobar bronchus at a site > 2 cm from the carina; that survival rate was not significantly different from survival for stage IA (p = 0.1573). Multivariate analysis showed that tumor diameter (p = 0.0272) was of prognostic importance in stage IA, while tumor diameter (p = 0.0005) and histologic grade (p = 0.0092) were relevant in stage IB. CONCLUSION: The new staging guidelines for differentiated small-cell bronchogenic carcinoma are nearer to prognostic reality given that survival for stage IA patients is significantly longer than for stage IB patients. However, the method continues to have shortcomings in that it fails to achieve one of its main objectives, namely prognostic homogeneity for each subgroup, as indicated by problems related to variables of tumor extension such as diameter, involvement of the visceral pleura or bronchial location, apart from other factors that affect survival.

Carcinoma, Bronchogenic↗