PubMed HealthSearch

Biomedical subjects

P Serra

Publications and source records attributed to P Serra.

At least 19 recordsLinked to original sources

Oxygen effect on O2 deficit and VO2 kinetics during exercise in obstructive pulmonary disease.

We evaluated the effect of supplemental O2 on energy metabolism of hypoxemic humans by measuring O2 uptake (VO2) kinetics and other cardiorespiratory parameters in nine male chronic obstructive pulmonary disease (COPD) patients and seven age-matched control subjects (on air and on 30% O2) at rest and during moderate cycle ergometer exercise. Heart rate, ventilation, VO2, CO2 output, respiratory exchange ratio, O2 cost of work, and work efficiency were measured with a computerized metabolic cart; O2 deficit and VO2 time courses were calculated. In COPD patients, 30% O2 breathing resulted in 1) reduction of O2 deficit (from 488 +/- 34 ml in air to 398 +/- 27 ml in O2; P < 0.05) and phase 2 VO2 time constant (from 116 +/- 13 s in air to 74 +/- 12 s in O2; P < 0.05); 2) a smaller steady-state increment in CO2 output than in room air (315 +/- 17 ml/min in O2 vs. 358 +/- 27 ml/min in air; P < 0.02), which resulted in a lower exercise respiratory exchange ratio (0.75 +/- 0.02 in O2 vs. 0.80 +/- 0.02 in air; P < 0.02); and 3) reduced steady-state ventilation (22.6 +/- 1.0 l/min in O2 vs. 25.4 +/- 1.1 l/min in air; P < 0.05). In conclusion, 30% O2 breathing accelerated exercise VO2 kinetics in mildly hypoxemic COPD patients. The observed VO2 kinetics improvement with O2 supplementation is consistent with an enhancement of aerobic metabolism in skeletal muscles during moderate exercise.

Aged

Nutritional state and exercise tolerance in patients with COPD.

We hypothesized that in patients with COPD, poor nutritional status adversely influences exercise tolerance by limiting aerobic capacity of exercising muscles. In 28 patients with stable COPD, we correlated nutritional status with gas exchange indexes obtained during maximal incremental cycle ergometer exercise and with respiratory function parameters. On the basis of percent of ideal body weight (%IBW), patients were divided into three groups (GP): GP1 (n = 8, %IBW < 90); GP2 (n = 13, %IBW > or = 90 < 110); and GP3 (n = 7, %IBW > or = 110). When compared with normally nourished individuals (GPs 2 and 3), malnourished GP1 patients showed greater reduction in maximal workload and in peak O2 uptake (VO2 peak), with earlier onset of metabolic acidosis (anaerobic threshold [AT]); in addition, indexes reflecting O2 cost of ventilation were higher in GP1. Nutritional status could be correlated with exercise tolerance (VO2 peak, r = 0.82, p < 0.0001), with onset of metabolic acidosis (AT, r = 0.69, p < 0.0001) and with dead space/tidal volume ratio (VD/VT, r = -0.59, p < 0.001). Body weight was inversely correlated with indexes that are likely to reflect the increase in O2 cost of ventilation. We conclude that in patients with stable COPD, (1) malnutrition significantly affects muscle aerobic capacity and exercise tolerance, and (2) high wasted ventilation and O2 cost of ventilation may be responsible for the weight loss.

Aged

Cardiopulmonary exercise testing in the evaluation of patients with ventilatory vs circulatory causes of reduced exercise tolerance.

INTRODUCTION: Cardiopulmonary exercise testing (CPX) is considered a useful procedure in the evaluation of circulatory, ventilatory, or mixed origin of reduced exercise tolerance. Our study was designed to compare CPX and a standard clinical-instrumental approach in the evaluation of patients with cardiopulmonary disorders. METHODS: Fifty-seven patients (31 male, 26 female; mean [+/- SE] age, 60 +/- 2 years) were studied. Each patient was evaluated by two different observers: one used standard clinical criteria, the other used gas exchange indexes, monitored during a maximal incremental CPX, performed on a cycle ergometer. Cardiac output (CO), at rest and at submaximal work level, was also obtained. RESULTS: In 46 patients (80.7 percent), a concordant evaluation was reached by the two observers (24 were found to have a predominant ventilatory disorder, 22 to have a circulatory disorder); among these, in subjects considered to have circulatory impairment, the maximal CO/maximal workload ratio was significantly lower than in the ventilatory group; in those with ventilatory impairment, the reduced exercise tolerance correlated with the resting spirometric values. In the remaining 11 patients (19.3 percent), CPX better defined the underlying pathophysiology of exercise limitation: in 10 of them, clinically classified as having a mixed or predominantly ventilatory disorder, a greater importance of the circulatory component was detected; 4 had evidence of pulmonary vascular impairment (high VE/VCO2 at anaerobic threshold). CONCLUSIONS: Our study confirmed the sensitivity of CPX in the evaluation of a reduced exercise tolerance in dyspneic patients with cardiopulmonary conditions; when compared with a clinical-laboratory approach, in some patients it allowed the detection of an underestimated circulatory component causing exercise limitation.

Aged

Aorto-femoral graft infections: a clinical and microbiological analysis.

A 5-year experience of 19 aortic graft infections is reviewed. Of these, 13 (68%) had a late onset (more than 4 months after graft implantation) and usually presented with anastomotic pseudo-aneurysm or thrombosis. The remaining six infections (32%) had an early onset and presented more often with surgical wound infection. Aorto-enteric fistulae and inguinal sinus tracts were observed in both early and late onset infections. Coagulase-negative staphylococci (all slime negative, oxacillin susceptible strains) were the prevalent pathogens in both groups of infections and were isolated in six (32%) patients. Next most commonly seen were Pseudomonas aeruginosa in four (21%) patients, Enterococcus spp. in three (16%) patients, Staphylococcus aureus in three (16%) patients, other bacteria in six (32%) patients. No organisms were isolated in three (16%) patients. Mortality and major amputation rates were 47.3% and 31.6%, respectively. The therapeutic procedures included total graft removal (15 patients), partial graft excision (two patients), partial graft excision followed by total graft removal (one patient) and local treatment without graft removal (one patient). Six patients recovered, including two who underwent total graft removal associated with a non-conventional 'in situ' graft replacement and one patient treated conservatively with local treatment and antibiotics. The three patients undergoing partial graft excision showed signs of active infection of the residual graft.

Adult

Physical violence in the couple relationship: a contribution toward the analysis of the context.

This article proposes an analysis of the contextual elements of physical violence occurring within the couple relationship. According to this analysis, the batterer acquires power of a moral nature while the victim plays the role of the accused. After violence occurs, reconciliation with the batterer relieves the victim of her role as the suspect, the guilty one. In the course of the analysis, it is argued that the perception of physical violence in all its forms is characterized by dichotomies that are typical of our culture (subject/object, mind/body, ethics/knowledge, and so on). Attention is drawn also to the incongruity between the victim's requests for help and the kind of response she usually receives. It is intended, moreover, to cast new light on the tension-violence-contrition cycle described by Lenore Walker.

Adult

High-level aminoglycoside resistance among enterococci: evaluation of an agar screen susceptibility test.

Seventy-five enterococci from infected (63 isolates) and colonized (12 isolates) patients hospitalized in various divisions of the Policlinico Umberto I, University of Rome, were in vitro studied for high-level resistance (HLR) to gentamicin (HLRG) and streptomycin (HLRS) with adoption of a standard broth dilution and an agar screen test. The employed procedures provided equal results for 100% of the 75 isolates. Of these, 21 (28%) showed HLRG and 43 (57%) HLRS. Combined HLRG and HLRS were found in 18 (24%) isolates, whereas HLRS or HLRG alone were found in 25 (33%) and 3 (4%) isolates respectively. It is concluded that HLR to aminoglycosides may represent a major problem in Italian institutions. Along with other established procedures, the agar screen test employed in the study may be used to detect this antibiotic resistance in enterococci.

Drug Resistance, Microbial

4-week treatment of streptococcal native valve endocarditis with high-dose teicoplanin.

The efficacy and safety of a 4-week course of intravenous teicoplanin (500 mg every 12 h for the first 2 days and 10 mg/kg of body weight every 24 h thereafter) in the treatment of streptococcal native valve endocarditis in 20 patients were evaluated. All blood isolates were inhibited by a concentration of 0.12 micrograms of teicoplanin per ml. Serum bactericidal activity levels were measured 1/2 and 24 h after antibiotic infusion on days 5 to 7 of therapy in 19 patients, and titers of greater than or equal to 1:32 and greater than or equal to 1:8, respectively, were obtained with 17 patients (89%). On the other hand, for two patients who were infected with teicoplanin-tolerant Streptococcus bovis, serum bactericidal activity levels of less than 1:2 were found. Of 20 patients, 4 were excluded from further analysis because of protocol violation or prosthetic valve infection. Of the remaining 16 patients, 6 did not complete teicoplanin therapy because of early death (1 patient) or drug fever (5 patients). Among patients who developed drug fever, three who discontinued teicoplanin by day 15 were switched to penicillin therapy, whereas the remaining two, who discontinued teicoplanin on day 22 and 25, respectively, did not receive any further therapy and have shown no relapse during the follow-up. Of 10 patients who completed trial therapy, 9 were cured and 1 relapsed. It is concluded that a 4-week course of high-dose teicoplanin may be a useful regimen for home treatment of selected cases of streptococcal native valve endocarditis. However, drug fever and infection with teicoplanin-tolerant S. bovis may be factors of concern with this therapeutic approach.

Endocarditis, Bacterial

Intravenous ciprofloxacin for the treatment of severe infections.

Intravenous ciprofloxacin at a daily dosage of 400 mg divided in two doses was administered to 19 patients with severe infections caused by ciprofloxacin-susceptible bacteria. These infections included: 11 surgical would infections, 5 soft tissue infections, 2 respiratory tract infections, 1 urinary tract infection. The offending pathogens were: 8 coagulase-negative staphylococci, 3 Staphylococcus aureus, 3 Pseudomonas aeruginosa, 2 Proteus spp., 1 Escherichia coli, 1 Branhamella catarrhalis, 1 Klebsiella ozenae and 1 Serratia liquefaciens. Overall, 17 of 19 infections (89%) showed a satisfactory clinical response to trial therapy (15 cures and 2 improvements). Microbiological eradication was observed in 17 out of 20 isolated pathogens. Emergence of resistance to ciprofloxacin occurred in 1 coagulase-negative Staphylococcus and was associated with clinical failure. No side effects were observed. We conclude that intravenous ciprofloxacin may represent efficacious and safe therapy of severe infections; however close microbiological monitoring seems to be necessary to evaluate the emergence of resistance during quinolone therapy.

Adult

Comparative efficacy of cefotetan and clindamycin plus amikacin as antimicrobial prophylaxis for major head and neck surgery.

A total of 41 patients were randomly allocated to receive either cefotetan (total dose, 20 g) or clindamycin (total dose, 12 g) plus amikacin (total dose, 5 g) as perioperative antimicrobial prophylaxis for major head and neck surgery. The two groups were similar in age, male to female ratio, stage of cancer, and the various types of surgery. No patient received radiotherapy or chemotherapy before surgery. The wound infection rate was 4% in the group of patients receiving cefotetan and 0% in the group receiving clindamycin plus amikacin. No major side effects were observed in either group. On the basis of this study a five-day perioperative course with cefotetan may be considered effective antimicrobial prophylaxis in patients undergoing major head and neck oncologic surgery.

Amikacin

Regulation of atrial natriuretic peptide release in normal humans.

Atrial volume, pressure, and heart rate are considered the most important modulators of atrial natriuretic peptide (ANP) release, although their relative role is unknown. Continuous positive-pressure breathing in normal humans may cause atrial pressure and atrial volume to go in opposite directions (increase and decrease, respectively). We utilized this maneuver to differentially manipulate atrial volume and atrial pressure and evaluate the effect on ANP release. Effective filling pressure (atrial pressure minus pericardial pressure) was also monitored, because this variable has been proposed as another modulator of ANP secretion. We measured right atrial (RA) pressure, RA area, esophageal pressure (reflection of pericardial pressure), and RA and peripheral venous ANP in seven healthy adult males at rest and during continuous positive-pressure breathing (19 mmHg for 15 min). Continuous positive-pressure breathing decreased RA area (mean +/- SE, *P less than 0.05) 13.6 +/- 1.1 to 10.5 +/- 0.8* cm2, increased RA pressure 4 +/- 1 to 16 +/- 1* mmHg, increased esophageal pressure 2 +/- 1 to 12 +/- 1* mmHg, and increased effective filling pressure 2 +/- 0 to 4 +/- 1* mmHg. RA ANP increased from 67 +/- 17 to 91 +/- 18* pmol/l and peripheral venous ANP from 43 +/- 4 to 58 +/- 6* pmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Turner's syndrome, fibromuscular dysplasia, and stroke.

We report a 43-year-old woman who presented with a right frontoparietotemporal ischemic stroke. She had been diagnosed with Turner's syndrome during childhood and had a history of chronic estrogen therapy. Cerebral angiography showed lesions characteristics of fibromuscular dysplasia involving the right internal carotid and right vertebral arteries. We are not aware of any previous reports describing an association between fibromuscular dysplasia and Turner's syndrome. Although chronic estrogen therapy cannot be ruled out as a cause of this patient's stroke, we suggest a possible etiologic relation between these two entities.

Adult

Pharmacologic elevation of blood inorganic phosphate in hypoxemic patients with COPD.

We have shown that in patients with COPD, myocardial efficiency during exercise is enhanced following acute elevations of plasma phosphate (Pi). A decrease in Hb-O2 affinity (increase in P50) was not responsible for the improvement. We postulated that the physiologic benefit was due to the acute reversal of a subclinical myocardial Pi depletion. To further test this hypothesis in a chronic state, we studied nine stable hypoxemic (PaO2 = 64 +/- 2 mm Hg [+/- SEM]) patients with COPD over five weeks: two weeks at normal plasma Pi; and three weeks at elevated plasma Pi, induced by etidronate disodium (Didronel; 750 mg orally daily). Administration of etidronate disodium increased (p less than 0.05) plasma level of Pi (4.4 +/- 0.2 to 5.8 +/- 0.1 mg/dl), RBC level of Pi (3.1 +/- 0.2 to 4.1 +/- 0.2 mg/dl), RBC level of 2,3-DPG (16.2 +/- 1.1 to 21.3 g+/- 1.3 mumol/g of Hb) and P50 (23.7 +/- 0.5 to 26.0 +/- 0.8 mm Hg). At the end of the treatment, the widening of the C(a-v)O2 with exercise (7.1 +/- 0.8 to 8.9 +/- 0.6 ml/dl) was less pronounced than under control conditions (6.9 +/- 0.4 to 10.1 +/- 0.6 ml/dl; p less than 0.02); concomitantly, the crossover point (COP; the PaO2 below which a rightward-shifted Hb-O2 curve causes the C(a-v)O2 to become narrower rather than wider) increased (37 +/- 2 to 49 +/- 1 mm Hg). Indicators of myocardial work efficiency were not affected by etidronate disodium at rest or during exercise. We postulate that during exercise the potential beneficial effect of the rightward shift of the Hb-O2 curve upon cardiac function was negated by the fall of PaO2 to or below the COP level, a situation which would limit increases in tissue O2 extraction.

2,3-Diphosphoglycerate

Alveolar cell population in HIV infected patients.

Alveolar lymphocytosis, in the face of blood lymphopenia, is a common finding among patients with AIDS. We studied by bronchoalveolar lavage (BAL), the alveolar cell profile of 43 human immuno deficiency virus (HIV) seropositive patients divided into three groups involving the advanced stages of the disease: group A (n = 9; CDC III), ambulatory individuals without systemic or respiratory symptoms; group B (n = 15; CDC IV) patients admitted for evaluation of fever of unknown origin (FUO) without pulmonary involvement; group C (n = 19; CDC IV), patients admitted for evaluation of an acute pulmonary condition. Sex, age and risk factor were comparable among the groups. Alveolar lymphocytosis was found in no group A patients, in 2 out of 15 group B patients (both with P. carinii lung infection) and in all group C patients, where pulmonary involvement was due to opportunistic infection or to nonspecific interstitial pneumonitis. Our findings suggest that in patients with advanced HIV infection alveolar lymphocytosis may be an expression of a concomitant process within the lungs either clinically manifest or inapparent, or possibly related to HIV primary lung involvement.

Acquired Immunodeficiency Syndrome

Erysipelothrix rhusiopathiae endocarditis.

A case of Erysipelothrix rhusiopathiae endocarditis involving the aortic and mitral valves in a 70-year-old male farmer is reported. The onset of infection was insidious, with a five-month history of low grade fever, malaise and a 20 kg weight loss. The patient eventually developed severe heart failure requiring surgery and died postoperatively of Pseudomonas aeruginosa pneumonia. In vitro studies showed the isolate to be highly susceptible to penicillin, ciprofloxacin and ofloxacin, and resistant to vancomycin.

Aged