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J Jorquera

Publications and source records attributed to J Jorquera.

10 recordsLinked to original sources
PubMed2005

Physiological and clinical effects of diurnal noninvasive ventilation in hypercapnic COPD.

To assess the clinical impact of noninvasive mechanical ventilation (NIMV) on stable hypercapnic chronic obstructive pulmonary disease, changes in exercise capacity, dyspnoea and simple physiological parameters were evaluated. The time course of these effects during treatment and recovery was also assessed. Patients were randomly allocated to NIMV (n=27) or sham-NIMV (n=15), applied 3 h.day-1, 5 days a week, for 3 weeks. A 6-min walking distance (6MWD), arterial blood gases, spirometry, pattern of breathing, mouth occlusion pressure (P0.1), and respiratory system impedance (P0.1/tidal volume (VT)/inspiratory time (tI)) were measured weekly during treatment and 2 weekly during follow-up. Transition dyspnoea index (TDI) was also measured. During NIMV, carbon dioxide arterial tension decreased progressively, concomitantly with a slow deep pattern of breathing, a proportional increase in the forced expiratory volume in one second (FEV1), the forced vital capacity and significant reductions of P0.1 and P0.1/VT/tI. The 6MWD improved by a mean of 76 m after NIMV, and by 73 m and 61 m 1 and 2 weeks, respectively, after treatment. Dyspnoea improved with a mean TDI of three points. Changes in 6MWD were highly related to TDI and to a lesser extent to changes in FEV1 (r=0.60). The current authors conclude that noninvasive mechanical ventilation has significant and sustained clinical impact in stable hypercapnic chronic obstructive pulmonary disease.

Aged↗
PubMed2001

[The six minute walking test elicits lung hyperinflation in patients with severe chronic obstructive lung disease].

BACKGROUND: Exercise tolerance in patients with COPD is highly variable and poorly related to airways obstruction assessed by FEV1. These patients develop dynamic hyperinflation (DH) during an incremental exercise test which can be evaluated through a reduction in inspiratory capacity (IC). AIM: To evaluate: a) if the six minute walking test (6 MWD) induce DH reducing IC, b) if the reduction in IC is related to tidal expiratory flow limitation at rest (FL). SUBJECTS AND METHODS: Thirty eight stable COPD patients (28 FL and ten non FL during resting breathing, determined by the negative pressure technique). Inspiratory capacity was measured before and immediately after the 6 MWD test. Dyspnea, SpO2 and heart rate were measured before and after the test. RESULTS: Inspiratory capacity was lower in FL patients as compared to patients without FL (p < 0.005). Although no differences were found between groups in 6 MWD, dyspnea and HR, a significant reduction in IC after the walking test was observed only in FL patients (p < 0.0001). In addition, SpO2 fell significantly (p < 0.0001) after walking in the same group. CONCLUSIONS: Our results demonstrate that a moderate exercise such as the walking test induces DH and hypoxemia in patients with COPD and FL and stresses the importance of assessing DH by measuring IC in these patients.

Aged↗
PubMed1996

[Antineutrophil cytoplasmic antibodies and nonspecific ulcerative colitis].

We studied the presence of antineutrophil cytoplasmic antibodies in 16 patients with idiopathic ulcerative colitis, using an indirect immunofluorescence technique and specific ELISA for myeloperoxidase and proteinase 3. Twelve patients had an active disease and in ten, antineutrophil cytoplasmic antibodies were positive, with a predominantly perinuclear distribution and without specificity for myeliperoxidase or proteinase 3. These antibodies were negative in the four patients with inactive disease. It is concluded that antineutrophil cytoplasmic antibodies could be serologic indicators of disease activity in patients with ulcerative colitis.

Adult↗
PubMed1993

Triads and transverse tubules isolated from skeletal muscle contain high levels of inositol 1,4,5-trisphosphate.

We measured the content of inositol 1,4,5-trisphosphate in sarcoplasmic reticulum, transverse tubules, and triads isolated from frog skeletal muscle, as well as in triads isolated from rabbit skeletal muscle. We found that acid extracts of both transverse tubules and triads contained significant amounts of inositol 1,4,5-trisphosphate, in the range of 300-400 pmol/mg of protein as determined by a radioreceptor assay, whereas no detectable amounts were found in sarcoplasmic reticulum vesicles. The identity of inositol 1,4,5-trisphosphate in the extracts was confirmed by comigration with [3H]inositol 1,4,5-trisphosphate on polyethyleneimine-cellulose plates, and by phosphorylation to inositol 1,3,4,5-tetrakisphosphate using the inositol 1,4,5-trisphosphate 3-kinase present in muscle extracts. These findings may have important physiological implications. First, the results indicate that the muscle plasma membrane regions differentiated as transverse tubules contain high amounts of inositol 1,4,5-trisphosphate, suggesting that they might possess a high density of binding sites for this compound. Second, since inositol 1,4,5-trisphosphate has been proposed as a chemical transmitter in excitation-contraction coupling in skeletal muscle, our finding that this second messenger is present in high density at the site of coupling may contribute to the understanding of its role in this process.

Animals↗
PubMed1992

[2 rare cases of a presentation of endometrial cancer].

Two cases of endometrial carcinoma with an atypical presentation are analyzed. The first case was formerly submitted to pelvic irradiation because a cervical carcinoma, and the second case to a long-term tamoxifen co-adjuvant therapy on account of a breast carcinoma. The risk for seconds primaries carcinomas and the eventual association of pelvic radiation and tamoxifen therapy with a subsequent endometrial carcinoma are discussed.

Adnexa Uteri↗