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T Perez

Publications and source records attributed to T Perez.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Comparative study of the global left ventricular ejection fraction obtained by ECG gated perfusion MIBI and thallium scintigraphy].

The isotopic LVEF was measured by a planar method with injection of a product visualising the ventricular cavity. Perfusion was assessed by Thallium and sesta MIBI. The investigation of ischaemia and assessment of wall motion in the coronary patient, therefore, requires two isotopic methods. The Cedars Sinai group have developed a programme allowing acquisition of a perfusion tomoscintigraphy in the cardiac cycle after injection of MIBI. This programme automatically detects the endocardial borders and calculates the LVEF. This provides a study of function and perfusion in a single investigation. However, MIBI is not considered by all as a good marker of viability, contrary to Thallium. And the acquisition of Thallium tomography with ECG gating may pose problems because of the low counting statistic. Several authors have therefore studied the possibility of using it for assessing left ventricular function. The authors have then compared LVEF with MIBI and with Thallium in 72 patients. The Thallium LVEF was 33.62% +/- 15.79%; that of MIBI was 32.51% +/- 14.73%. ThalEF = MIBI EF x 1.02 + 0.34 (r = 0.955). The mean of the standard deviation was 1.09. In conclusion, the EF measured by Thallium tomography with ECG gating was closely correlated to that obtained with MIBI. These results suggest that myocardial viability, ischaemia and function may be studied in routine daily practice with a single injection, so improving patient comfort and reducing the costs of the procedures.

Adult↗
PubMed1997

Pulmonary function tests and high resolution computed tomography of the lungs in patients with rheumatoid arthritis.

OBJECTIVE: To compare the results of pulmonary function tests (PFTs) and high resolution computed tomography (HRCT) of the lungs in rheumatoid arthritis (RA) patients. METHODS: Sixty eight patients (54 women, 14 men) fulfilling the revised criteria for RA were consecutively included in a transversal prospective study. Their mean age was 58.8 years (range: 35-82) and the mean duration of the disease was 12 years (range: 5-16). Rheumatoid factor was positive in 52 patients (76.5%). Fifty two patients (76.5%) were lifelong non-smokers. Detailed medical and drug histories were obtained. PFTs comprised spirometry and gas transfer measurements. Results for PFTs were expressed as percentage of predicted values for each individual adjusted for age, sex, and height. HRCT was undertaken with a Siemens Somatom Plus. RESULTS: A significant decrease of FEV1/ FVC, FEF25%, FEF50%, FEF75%, FEF25-75%, and TLCO was observed (p < 0.05) and 13.2% of the patients had a small airways involvement defined by a decrease of FEF25-75% below 1.64 SD. The most frequent HRCT findings were: bronchiectasis (30.5%), pulmonary nodules (28%), and air trapping (25%). The patients with small airways involvement had a high frequency of recurrent bronchitis (75% v 34%, p = 0.05) and bronchiectasis (71% v 23%, p = 0.019). The patients with bronchiectasis were characterised by low values of FEV1, FVC, FEF25-75%, and TLCO (p < 0.01), a high prevalence of small airways involvement (29% v 5%, p = 0.019), and a low prevalence of HLA DQA1 *0501 allele (14% v 33%, p < 0.05). CONCLUSION: This study suggests a significant association between small airways involvement on PFTs and bronchiectasis on HRCT in unselected RA patients.

Adult↗
PubMed1997

Sequential evaluation of pulmonary function and bronchial hyperresponsiveness in patients with nasal polyposis: a prospective study.

Nasal polyposis (NP) is commonly associated with nonspecific bronchial hyperresponsiveness (BHR) and/or asthma. The aim of this prospective study was to investigate the changes of pulmonary function and BHR in patients with nasal polyposis. Forty-four consecutive patients with NP were included in the study and were followed for 12 mo. Nonspecific BHR was assessed by a carbachol challenge test to determine the provocating dose (PD20) necessary to decrease FEV1 by 20% from baseline values; 17 of 22 patients who demonstrated BHR also exhibited asthma. Spirometric measurements and carbachol challenge were performed before initiating any treatment and 12 mo later. All patients were treated first with beclomethasone (600 microg/d). Intranasal ethmoidectomy was performed in 23 patients who did not improve when treated with topical steroids alone (nonresponders); in contrast, 21 patients were successfully treated with beclomethasone alone (responders). PD20 significantly decreased in the group of nonresponders (p = 0.018), whereas it remained unchanged in responders (p = 0.95). FEV1 (% pred) and FEF25-75 (% pred) significantly decreased in nonresponders (p < 0.001), whether BHR existed or not, whereas no significant change was observed in responders. Our results demonstrate that nonresponders who required nasal surgery exhibited an enhancement of BHR and a slight but significant decrease of FEV1 and FEF25-75 values. However, no change in pulmonary symptoms and/or asthma severity occurred. Clinical and functional follow-up of these patients should assess the long-term evolution of these parameters and their clinical relevance.

Adolescent↗
PubMed1997

Rothia dentocariosa: two new cases of pneumonia revealing lung cancer.

Pneumonia due to Rothia dentocariosa is extremely rare: only 1 case of pneumonia due to this pathogen has been reported in an immunocompromised patient with acute myelocytic leukemia. In this report, 2 new cases of Rothia dentocariosa pneumonia are described in 2 patients with lung cancer. This opportunistic pulmonary agent, belonging to the oro-pharyngeal flora, is also known to cause endocarditis in patients with underlying cardiac pathology.

Actinomycetales Infections↗
PubMed1997

[Chylothorax and sarcoidosis].

The association of sarcoidosis and chylothorax is rare. A patient aged 64 presented with mediastinal sarcoidosis. Two years after the diagnosis he developed a right chylothorax. The computed tomographic examination showed a retraction of the right hemithorax associated with large mediastinal nodes, without signs of interstitial lung disease. Pulmonary function tests revealed a restrictive ventilatory defect with a Forced Vital Capacity (FVC) of 53% and a Forced Expired Volume in one second (FEV1) of 54% from the predicted values; the FEV1/FVC ratio was 78%. Steroid therapy was started at 1 mg per kilogram per day for three months then progressively decreased to 15 mg per day. Inspite of the steroid therapy there was as well biological evidence of continued disease activity (bronchoalveolar lavage lymphocytosis and increased serum angiotensin converting enzyme), as persistence of pleural effusion and mediastinal adenopathy; the contraction of the right hemithorax increased. Restrictive ventilatory defect worsened with a FVC of 44% and an FEV1 of 47% of the predicted values. The presence of a significant contraction of the hemithorax and of a severe restrictive ventilatory defect suggested the existence both of pleural fibrosis and of a compression of the main lymphatic pathways responsible for the chylothorax.

Adrenal Cortex Hormones↗
PubMed1996

[Stunned myocardium or hibernating myocardium? Apropos of a case].

The authors relate a case report of unstable angina pectoris accompanied by a well-documented stunned myocardium phenomenon. Stunned and hibernating myocardium resulting from an acute or chronic coronary ischaemia on the myocardium are notions which widely govern revascularisation indications, especially after a myocardial infarction. At present, their detection is based on isotopic methods and stress echocardiography.

Angina, Unstable↗
PubMed1996

Inspiratory muscle strength and endurance in steroid-dependent asthma.

The adverse effect of long-term steroid treatment on respiratory muscle function remains controversial. We evaluated inspiratory muscle strength and endurance in steroid-dependent asthmatics in comparison with other asthmatics or with patients with chronic obstructive pulmonary disease exhibiting a comparable level of lung hyperinflation. Inspiratory muscle function was assessed by maximal inspiratory pressure (Pimax) and by an incremental inspiratory threshold loading test in 19 patients who had had steroid-dependent asthma (SDA) requiring a mean daily dose of 20.7 +/- 0.8 mg prednisone for 5 +/- 1.4 yr. They were compared with 16 healthy control subjects, 30 patients with COPD, and 16 patients with non-steroid-dependent asthma (NSDA). Pimax as percentage of predicted values (%Pimax) was not significantly different in patients with SDA (77 +/- 5%) or NSDA (83 +/- 6%) than in control subjects (93 +/- 4%). In contrast, %Pimax was lower in patients with COPD (59 +/- 4.4%) than in those with SDA or NSDA (p < 0.05) or the control subjects (p < 0.0001). A significant correlation was found between %Pimax and hyperinflation assessed by the FRC/TLC ratio (r = 0.42; p < 0.001). Inspiratory endurance, defined as the ratio of maximal peak inspiratory pressure sustained for 2 min to individual Pimax (Plim2/Pimax), was significantly lower in the SDA (43 +/- 3%; p < 0.0001), NSDA (65 +/- 4%; p = 0.01), and COPD (55 +/- 3%; p < 0.0001) groups than in the control group (76 +/- 2%). Plim2/Pimax was also lower in patients with SDA than in those with COPD (p = 0.0073) or NSDA (p < 0.0001). Hyperinflation plays a major role in inspiratory muscle dysfunction associated with obstructive lung disorders, but the finding of a significantly decreased endurance in patients with SDA when compared with patients with COPD, despite a lower level of hyperinflation in the former group, points to a deleterious effect of long-term corticosteroid treatment on inspiratory muscle function in asthmatics.

Asthma↗
PubMed1995

Maternal-to-fetal transfer of 5-methyltetrahydrofolate by the perfused human placental cotyledon: evidence for a concentrative role by placental folate receptors in fetal folate delivery.

Folates play a vital role in cellular processes that are essential for fetal growth and viability. Thus the human placenta, which contains high-affinity membrane-associated placental folate receptors (PFRs), maintains a concentrative maternal-to-fetal flux of the vitamin under conditions of minimal dependence on variations of maternal dietary intake. To define transplacental folate transport and the role of PFRs in this mechanism, we utilized the isolated perfused human placental cotyledon. In closed system perfusions with 10 nmol/L 5-methyltetrahydrofolate, placental binding was rapid and extensive (47%), with a gradual maternal-to-fetal transfer of 5-methyltetrahydrofolate. Although hydrophilic PFRs were released into the fetal perfusate, PFR-bound folates constituted only a fraction of net transplacental folate transport. Transfer was bidirectional, not saturable, not inhibited by anion channel blockers, and dependent on perfusate levels. Placental binding far exceeded transfer, and pulsing the maternal circuit with tritiated 5-methyltetrahydrofolate, followed by washout of unbound radiolabel and rechallenge with unlabeled 5-methyltetrahydrofolate or folate, led to release of bound tritiated 5-methyltetrahydrofolate, illustrating reversible binding. Perfusion with the N-hydroxysuccinimide ester of folic acid eliminated essentially all 5-methyltetrahydrofolate binding to PFRs, while increasing net maternal-to-fetal transfer of the vitamin. Finally, because it has been suggested that impaired placental transport of folate may be linked to the fetotoxic effects of ethanol, the effect of this compound on the above processes was examined. An acute 6-hour exposure to ethanol (2.5 to 3.1 mg/ml) had no effect (p > 0.05) on net maternal-to-fetal transfer of 5-methyltetrahydrofolate. These studies suggest that net maternal-to-fetal transfer is a process consisting of two steps. First is the concentrative component in which circulating 5-methyltetrahydrofolate is bound to (captured by) PFRs on the maternally facing chorionic surface. Although kinetics favor binding, there is a dynamic state wherein a gradual release of 5-methyltetrahydrofolate from this pool can add to incoming circulating folates to generate an intervillous blood level approximately 3 times that in the maternal blood. In the second step, folates are passively transferred to the fetal circulation along a downhill concentration gradient. This unique mechanism for transplacental folate transport may be applicable to other small relative molecular mass ligand nutrients that bind to high-affinity placental receptors.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1994

Concomitant chemoradiation prior to surgery in the treatment of advanced cervical carcinoma.

In patients with locally advanced cervical cancer, most of the treatment failures occur within the pelvis. In an attempt to improve local control, 40 patients with bulky tumors (stage IB > 5 cm, stage IIB with distal parametrial invasion, and stage III-IVA) were treated between 1988 and 1992 with concurrent chemoradiation (CCR). The whole pelvis received a midplane dose of 45 Gy over 33 days. Daily radiation dose was 1.8 Gy, with twice-daily fractionation in the last 20 patients. Chemotherapy was administered on the 1st and 21st days of radiation therapy (RT) consisting of cisplatin (60 mg/m2), followed by 5-fluorouracil (600 mg/m2/day continuous i.v. infusion) over 96 hr (and decreased to 40 and 400 mg/m2, respectively, in the last 23 patients). CCR was first followed by a single intracavitary application and then by a parametrial boost in stage IIB-III patients and in stage IVA patients with disease reaching the pelvis side wall. Then surgery (colpohysterectomy with lymphadenectomy or pelvic exenteration) was performed in 35 patients. Median follow-up time was 2.6 years (0.6-5.6 years). Acute toxicity (WHO grade 3-4 diarrhea) in 13 patients led to 6 RT interruptions and 4 incomplete RTs. One patient died of a septic episode without leukopenia after completion of CCR. Five postexenteration complications required a second surgical procedure, of which one patient died with tumor and small bowel fistula. One patient developed small bowel late complication and another patient developed urinary late complications. No postoperative or late complications were observed in patients treated with twice-daily fractionation. Pelvic control was achieved in 32 of 40 patients (81 and 74% in stage IB-IIB and stage III-IVA, respectively). Sites of failure were the pelvis (6 cases), metastases (7 cases), and both (2 cases). Two-year survival and DFS rates were 61 and 66%, respectively, in stage IB-IIB and 77 and 65% in stage III-IVA. High SCC-TA4 values significantly worsened DFS rates. In patients with stage III-IVA tumors, additional surgery could be an important component of this treatment strategy and may be compatible with CCR using twice-daily fractionation radiotherapy. However, these results must be confirmed by a large-scale prospective study.

Adult↗
PubMed1994

Pelvic staging of advanced and recurrent gynecologic cancers: contribution of endosonography.

From January 1988 to December 1992, 106 patients with advanced gynecologic cancer were preoperatively explored by clinical examination (CE) and endosonography (ESG) under anesthesia and by computed tomography (CT). Sixty-one tumors were primary and 45 recurrent; the main locations were cervical (73 cases), ovarian (10 cases), and endometrial (8 cases). All the patients were operated. This prospective study compares the data from clinical and imaging examinations with the histologic findings and the surgical reports. Accuracy of the CE, ESG, cytoscopy, and CT was respectively 79, 90, 82, and 80% for vesical involvement (ESG versus CT: P < 0.05). For vesicovaginal septum extension, accuracy of ESG (92%) was statistically better than that of CE (80%) and CT (77%). Accuracy of the CE, ESG, and CT was respectively 93, 97, and 89% for rectal involvement (ESG versus CT: P < 0.02). For rectovaginal septum extension, accuracy of ESG (96%) was statistically better than that of CE (85%) and CT (85%). Endosonography is valuable in the assessment of regional staging of advanced gynecologic cancers. Since it is realized during the clinical examination under anesthesia, this low-cost procedure is easily performed and provided no discomfort to the patients.

Adult↗
PubMed1994

Determinants of response to immunosuppressive therapy in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) response to corticosteroids and cytotoxic medications appears to be the most important determinant of survival. The purpose of this retrospective study was to analyse the determinants of response to immunosuppressive therapy with prednisone alone, or prednisone and cyclophosphamide, in IPF. Twenty five consecutive patients were studied. Initial evaluation in untreated patients included clinical, biological and functional parameters. Sequential evaluation by pulmonary function tests (forced vital capacity (FVC) and transfer factor of the lungs for carbon monoxide (TLCO)) was performed at a 3 month interval. Response to therapy was defined as an improvement in FVC and/or TLCO of more than 10% after 12 months, with maintenance of this improvement for at least another 12 months. Twelve of the 25 patients were classified as responders. A symptomatic disease of less than 12 months duration before onset of therapy related to response. FVC was more impaired in the group of responders when the comparison was limited to patients with an FVC of less than 90%. Bronchoalveolar lavage cell counts were not significantly different between responders and non-responders. Assessment of pulmonary function after 3 months of treatment was predictive of maintenance of the response or of even further improvement. Patients with improved FVC after 3 months of therapy had a significantly shorter symptomatic disease before onset of treatment (7.6 +/- 7.1 vs 20.2 +/- 18.6 months). A beneficial effect of addition of cyclophosphamide was observed only in patients who demonstrated an early but short-lived improvement to steroids. Adverse reactions of immunosuppressive therapy were noticed in 10 patients, and required discontinuation of treatment in six of them.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchoalveolar Lavage Fluid↗
PubMed1992

PAF acether release on antigenic challenge. A method for the investigation of drug allergic reactions.

This study describes an in vitro method to evaluate a PAF acether release test (PART) from white blood cells after antigenic challenge. PAF acether activity of the supernatant was tested by platelet aggregation. The aggregating power was abolished by using SRI 63-441 (Sandoz), a PAF acether inhibitor. This method was applied to 57 patients with allergic or pseudo-allergic reactions to drugs by using different drug protein conjugates. The results of PART were evaluated in relation to the clinical history (score of imputability) and to other tests (skin tests, lymphocyte transformation tests (LTT), IgE-RAST). A good correlation was found between the release of PAF acether and a high predictability score: sensitivity 75%, specificity 83.8%. PART also correlated with skin tests (75% agreement, n = 60), with LTT (67.7% agreement, n = 74) and in 65.6% of cases with positive penicillin IgE-RAST (n = 32). This method brings a new possibility for the investigation of drug-allergic and pseudo-allergic reactions.

Antigens↗
PubMed1992

[Plasma extravasation in the tracheo-bronchial airways. Mechanisms and physiopathological consequences in asthma].

Plasma extravasation (EP) is an important phenomenon during the course of inflammation. In asthmatic subjects, EP is produced not only in the walls of the airways, but also in the lumen. This has consequences for the bronchial calibre and the qualitative and quantitative characteristics of the secretions. Numerous experimental methods have been developed in animals in order to study EP induced in the airways by different stimuli. For the most part these are inapplicable in man where EP is generally validated in an indirect fashion by measuring the quantity of certain plasma proteins, such as albumin in the secretions or the bronchoalveolar lavage. EP is linked to an increase in the permeability of the vessels, notably this is situated in the subepithelial zone. It is influenced by the appearance of disruption between the endothelial cells and possibly amplified by an increased blood flow linked to vasodilatation. It is the association of these phenomena of epithelial hyperpermeability which favours the appearance of EP in the lumen. In experimental systems the greater part of the mediators implicated in the pathophysiology of asthma are capable of inducing EP in the airways. The perfecting of reliable and non-invasive methods of study is, however, necessary to achieve a perfect understanding of the role of EP in the pathophysiology of asthma or other inflammatory diseases of the bronchi and to assess the efficacy of this parameter of different therapeutic techniques.

Animals↗
PubMed1991

Imbalance of CD45R and CDw29 helper cell subsets after seven days of culture from penicillin hypersensitive patients.

Specific PBMC proliferation to penicillin represents one of the in vitro diagnostic procedures to show antigenic sensitization. Nine patients with suggestive clinical history of penicillin hypersensitivity, significant stimulation index in the lymphocyte transformation test (LTT), and increased CD25 expression were selected. Their phenotypic expression of T-cell subset markers was compared with that of six normal subjects after 7 days of culture. Higher percentages of CD45R and CDw29 positive cells were found in penicillin-hypersensitive patients. This group of patients showed a significantly (P less than 0.01) higher percentage of CD45R positive cells compared with normal subjects, after 7 days of culture. The percentage of CD45R cells did not differ between patients and normal subjects at day 0, and the progressive decrease of CD45R positive cells in culture of normal subjects was not observable in our patients. These results suggest that the patients with penicillin hypersensitivity have an imbalance of CD45R/CDw29 ratio after 7 days of culture, with a higher expression of CD45R positive cells.

Antigens, CD↗
PubMed1991

Increased TNF-alpha secretion by alveolar macrophages from patients with rheumatoid arthritis.

Tumor necrosis factor alpha (TNF) and interleukin-1 (IL-1) production by alveolar macrophages (AM) was evaluated in 17 rheumatoid arthritis (RA) patients without interstitial lung disease (ILD, Group 1) and 14 RA patients with clinical ILD (Group 2) in comparison with 10 control subjects. AM after recovery by bronchoalveolar lavage were selected by adherence, and then supernatants were collected after 3 or 24 h of culture. Results showed no modification of IL-1 synthesis in either group of RA patients. Spontaneous TNF production was significantly increased in Group 2 (2.5 +/- 0.5 ng/ml) as well as in Group 1 (2.4 +/- 0.4 ng/ml) compared with control subjects (0.43 +/- 0.1 ng/ml, p less than 0.001). In addition, AM from patients untreated or treated exclusively by nonsteroidal antiinflammatory drugs produced similar levels of TNF, whereas those receiving corticosteroids, second-line drugs (such as sulfasalazine, aurothiomalate, and methotrexate), or the combination of both therapy regimens released significantly less TNF. Interestingly, TNF was not different in both groups, but Group 2 had a markedly increased ratio of local immune complex to albumin in bronchoalveolar lavage fluid (0.47 +/- 0.12 versus 0.07 +/- 0.02 in Group 1; p less than 0.002). TNF thus appears an additional component of RA subclinical alveolitis in RA, but its prognostic value and its precise role in lung damage remain to be determined. Development of ILD requires certainly complex interactions of synergistic factors, possibly including local immune complexes detected in BAL fluids.

Antigen-Antibody Complex↗