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C Pinho

Publications and source records attributed to C Pinho.

At least 19 recordsLinked to original sources
PubMed2005

Overall characterization of cork dust explosion.

Explosibility and ignitability studies of air/cork dust mixtures were conducted in a near-spherical 22.7 L explosibility test chamber using pyrotechnic ignitors and in a furnace of 1.23 L. The suspension dust burned as air-dispersed dust clouds and the uniformity of the dispersion inside the chamber was evaluated through optical dust probes. The range of tested particle sizes went from a mass median diameter of 47.4 to 438.3 microm and the covered dust cloud concentration was up to 700-800 g/m(3). Measured explosion parameters included minimum explosible concentration, maximum explosion pressure, maximum rate of pressure rise and minimum autoignition temperature. The effect of dust particle size on flammability was evaluated and it was found that the minimum explosible concentration is around 40 g/m(3) and it is relatively independent of particle size below 180 microm. Maximum explosion pressure of 7.2 bar and maximum rate of pressure rise of 179 bar/s were detected for the smallest tested sizes. The limitations on the rates of devolatilization of the solid particles became rate controlling at high burning velocities, at high dust loadings and for large particle sizes. The effect of initial pressure on the characteristic parameters of the explosion was studied by varying the initial absolute pressure from 0.9 bar to 2.2 bar, and it was found that as initial pressure increases, there is a proportional increase of minimum explosion limit, maximum explosion pressure, and maximum rate of pressure rise. The influence of the intensity of the ignition energy on the development of the explosion was evaluated using ignition energies of 1000 J, 2500 J and 5000 J, and the experimental data showed that the value of 2500 J is the most convenient to use in the determination of minimum explosion concentration. The behavior of the cork dust explosion in hybrid methane air mixtures was studied for atmospheres with 2% and 3.5% (v/v) of methane. The effect of methane content on the characteristic parameters of the explosions was evaluated. The conclusion is that, the hazard and explosion danger rise with the increase of methane concentration, characterized by the reduction of the minimum dust explosion concentration. The minimum autoignition temperature obtained with the thermal ignition tests was 540 degrees C and the results have shown that this value is independent of particle size, for particles with mass median diameters below 80 microm.

Dust↗
PubMed2004

Acute necrotizing esophagitis: a large retrospective case series.

BACKGROUND AND STUDY AIMS: Acute necrotizing esophagitis is a rarely described entity. Its incidence has not yet been established, and its multifactorial etiology remains unknown. The aim of the present study was to establish the incidence, clinical presentation, endoscopic course, accompanying factors, and pathogenesis of the condition. PATIENTS AND METHODS: A retrospective analysis of clinical, laboratory, endoscopic and histological data and the clinical course in 29 patients with acute necrotizing esophagitis was carried out over a 5-year period. RESULTS: Acute necrotizing esophagitis was observed in 29 of 10 295 upper gastrointestinal endoscopies (0.28 %) carried out during the 5-year period. The average age of the patients was 75.24 years (range 40 - 91), and they were predominantly male. Eighty-three percent of the patients had comorbid conditions. In all cases, acute necrotizing esophagitis became evident with upper gastrointestinal bleeding, without hemodynamic stabilization in the majority of cases (75.9 %). The lesions predominantly affected the lower two-thirds of the esophagus (59 %), and there were coexisting abnormal endoscopic findings in 83 % of cases. Empirical supportive therapy, including oral nutritional rest, omeprazole, sucralfate (15 cases) and broad-spectrum antibiotics (7 cases) was provided. The condition resolved in all patients. Ten patients in the group died of other causes (coexisting illnesses). CONCLUSIONS: Acute necrotizing esophagitis was more commonly recognized than has previously been reported. It is a serious clinical entity that should be considered in the differential diagnosis of upper gastrointestinal bleeding, particularly in elderly patients. The prognosis depends more on the patient's advanced age and on comorbid illnesses than on the course of the esophageal lesions, which resolved in all patients in this series.

Acute Disease↗
PubMed2004

Wireless capsule endoscopy for evaluation of phenotypic expression of small-bowel polyps in patients with Peutz-Jeghers syndrome and in symptomatic first-degree relatives.

BACKGROUND AND STUDY AIMS: Peutz-Jeghers syndrome (PJS) is an inherited gastrointestinal hamartomatous polyposis disorder. Small-bowel intussusception and bleeding are the most common complications, and malignancy may also occur. Survey of the gastrointestinal tract, particularly of the small bowel, is difficult and current recommendations for management syndrome are ambiguous. We evaluated the feasibility of capsule endoscopy for identifying phenotypic expression of small-bowel polyps in patients with full-blown PJS and a previous diagnosis of gastrointestinal polyposis, and in symptomatic kindred of PJS patients with no previous diagnosis of gastrointestinal polyposis. PATIENTS AND METHODS: Two groups were studied: group A consisted of 14 patients with gastrointestinal polyposis, eight of whom had undergone previous small-intestine surgery; group B consisted of six symptomatic first-degree relatives of PJS patients; these patients had previous negative gastrointestinal endoscopic examinations. RESULTS: Numerous polyps were detected in all patients in group A. Most polyps were sessile, but the larger polyps tended to be pedunculated. Polyp density was highest in the jejunum (greater than in the ileum and duodenum). Seven patients had at least one large polyp (> 11 mm) and five of these patients subsequently underwent enteroscopy, which revealed that capsule endoscopy had correctly identified all the patients with large polyps, but had missed 20 % of the total number of large polyps in these patients. No polyps were detected by capsule endoscopy in group B patients, despite the excellent visualization of the small intestine. In all patients, the capsules were expelled within 24 hours, without complications, and the procedure was well tolerated. CONCLUSIONS: Capsule endoscopy is an effective and well-tolerated method for evaluating small-bowel pathology in patients with PJS.

Adolescent↗
PubMed2001

Helicobacter pylori genotypes are associated with clinical outcome in Portuguese patients and show a high prevalence of infections with multiple strains.

BACKGROUND: Clinical outcome of Helicobacter pylori infection is associated with virulence-associated bacterial genotypes. This study assessed the relationships between vacA, cagA and iceA genotypes and gastric diseases in Portuguese patients. METHODS: A total of 319 patients were endoscoped and gastric biopsy specimens were studied by PCR and reverse hybridization (LiPA). RESULTS: vacA genotypes s1/m1, s1/m2 and s2/m2 were observed in 53%, 14.5% and 32.5% of the cases, respectively. The majority (93.4%) of the s1 cases were s1b and 6.6% were s1a. Multiple vacA genotypes were found in 37.3% of the cases. Gastric ulcer and gastric carcinoma were associated with the presence of vacA s1 (P = 0.008 and P < 0.001, respectively) and vacA m1 genotypes (P = 0.007 and P < 0.001, respectively). Duodenal ulcers were associated with vacA s1 (P < 0.001) but not with the vacA m genotype (P = 0.221). cagA was present in 71.2% of the cases and was associated with duodenal ulcer (P < 0.001), gastric ulcer (P = 0.009) and gastric carcinoma (P < 0.001). iceA1 was found in 27.3% and iceA2 in 32.3% of the cases. In 36.7% of the isolates both iceA alleles were found, and 3.8% were negative for iceA. The iceA genotype was not associated with clinical outcome. CONCLUSIONS: vacA s1 and cagA+ H. pylori strains are associated with duodenal ulcer, gastric ulcer or gastric carcinoma. vacA m1 is associated with gastric ulcer or carcinoma but not with duodenal ulcer. Infection with multiple H. pylori strains is remarkably high in Portugal and is more frequent in duodenal ulcer patients.

Adolescent↗
PubMed2001

The distally based island superficial sural artery flap: clinical experience with 36 flaps.

The principles of neurocutaneous flaps, first described by Masquelet in 1992, represented a new concept in skin vascularization. The distally based superficial sural artery flap is an example of this kind of flap, which is supplied by the vascular axis that accompanies the sural nerve. The authors treated 36 patients with 36 distally based superficial sural artery flaps. All flaps survived, but six of them exhibited partial necrosis. No patient experienced anesthesia of the lateral side of the foot or neuroma at the donor site 12 months after surgery. The authors confirmed that this flap is very useful for soft-tissue reconstruction of the distal third of the leg and foot. Additionally they conclude that the principal advantages are that the blood supply is reliable, execution is easy and fast, the operation can be performed under regional anesthesia, the flap has a large arc of rotation, direct closure of the donor area is possible for small flaps, major arteries or nerves are not sacrificed, and excellent durability is achieved, even on weight-bearing areas. The major drawback is the donor site scar.

Adolescent↗
PubMed1998

[Microsurgical reconstruction of the head and neck: experience of 63 free flaps].

The authors present the experience of 63 clinical cases of microsurgical reconstruction of the head and neck. These reconstructions were accomplished by different microvascular free flaps which were selected according to the type, size and location of the defects. Fasciocutaneous, osteofasciocutaneous, adipofascial, myo, myocutaneous, myosseous, jejunum and great omentum flaps were applied. The etiology was traumatic in 10 cases, tumoral in 41 cases, congenital in 7 cases, iatrogenic in 3 cases and infectious in 2 cases. The reconstructed anatomical regions were the scalp in 6 cases, the skull base in 1 case, the orbit in 3 cases, the nose in 1 case, the hemiface in 7 cases, the lips in 1 case, the intraoral cavity in 21 cases, the mandible in 8 cases, the intraoral cavity plus mandible in 11 cases and the cervical esophagus in 1 cases. An analysis was made of surgical times, selection and survival rate of the free flaps and the morphofunctional quality of the reconstructions. Considering the good quality of reconstructions, the amelioration of quality of life and the low morbidity in these patients, microvascular free flaps are considered a first choice technique for head and neck reconstruction when the size and location of the defect prevents the use of local flaps.

Adult↗
PubMed1998

[Microsurgical reconstruction of the upper extremity. Experience with 24 free flaps].

The authors present the experience of 24 clinical cases of microsurgical reconstruction of the upper limb. These reconstructions were accomplished by different microvascular free flaps which were selected according to the type, size and location of the defects, having applied fasciocutaneous, adipofascial, myo, myocutaneous, tendofasciocutaneous, omentum flaps and 2nd toe transfers. The etiology was traumatic in 23 cases and tumoral in 1 case. A careful analysis was made for surgical times, selection and survival rate of the free flaps and the morphofunctional quality of the reconstructions. Microvascular free flaps are considered the choice technique for upper limb reconstruction, particularly for the hand in certain defects, considering the better anatomic and functional quality of the reconstructions.

Adolescent↗
PubMed1993

[Correlation between ventricular arrhythmia and geometric remodeling of the left ventricle in arterial hypertension].

PURPOSE: To study the presence and type of ventricular arrhythmias in patients with different geometric patterns of the left ventricle (LV). METHODS: Seventy-two patients with essential hypertension were divided in 4 groups, by the echocardiographic patterns: group I with concentric remodeling of the LV (normal LV mass with increased relative wall thickening); group II with concentric hypertrophy (both LV mass and relative wall thickening increased); group III with normal geometry of the LV (both LV mass and relative wall thickening normal); group IV, with eccentric hypertrophy (increased LV mass with normal relative wall thickening). The groups were compared by the quantity and quality of ventricular arrhythmia, measured by the number of ventricular ectopic beats (VEB) and episodes of ventricular tachycardia (VT) on Holter monitoring, and the presence of late potentials (LP) on signal-averaged electrocardiogram. RESULTS: Group I showed fewer VEB than group II (16.2 +/- 12.85 x 996.4 +/- 518.8, p < 0.05), and a statistic tendency to this result when compared with group IV (16.2 +/- 12.85 x 1634.2 +/- 1001.33, p = 0.063). When compared with group III, no statistical difference was found (16.2 +/- 12.85 x 19.8 +/- 14.81, p = NS). Episodes of VT and the presence of LP were noted only in groups II and IV. CONCLUSION: The group with concentric remodeling of the LV had fewer ventricular arrhythmias than hypertrophic groups, with characteristics closer to the patients with normal LV geometry.

Adult↗
PubMed1992

A computerized system for recording data in gastrointestinal endoscopy.

Over the past five years, the authors have developed a computerized system to record and store all the data pertaining to an endoscopic examination of the upper digestive tract. The system was designed to permit the easy storage and retrieval of data by personnel who lack computer skills and who may only have limited typing ability. The system allows for the storage and rapid retrieval of patients' individual records, as well as correction and/or deletion of these records. The system prints out copies of preliminary endoscopic findings and produces a final copy which contains histological and cytological findings. The program utilizes a standardized nomenclature, which however permits the introduction of each user's code in 16 areas of classification. It is possible to analyze statistically and correlate the stored data, permitting easy use for clinical studies. The uniformity of the methods for storage of and access to patients' records and data, along with the support of a central computer, allows multi-centre studies in the field of epidemiology. As of January 1991 30 endoscopic centres in Portugal have been equipped with this system. Overall the experience in these centres has been positive, with excellent or good participation in 76.7% of centres.

Endoscopy, Gastrointestinal↗
PubMed1992

[Myocardial infarction as a consequence of infective endocarditis in valvar bioprosthesis].

A sixteen year-old male, followed in the Unicamp Cardiology Clinic with a previous record of rheumatic heart disease and a biological mitral prosthesis, presented with infective endocarditis. In spite of a good initial response to antibiotic therapy, the patient died in two weeks. Autopsy disclosed endocarditis of the prosthetic valve and embolic occlusion of the circumflex branch of left coronary artery.

Adolescent↗
PubMed1992

[Gastric carcinoid associated with pernicious anemia].

A clinical case of a patient with pernicious anaemia and a carcinoid tumor of the gastric fundus is described. In the context of the case the relationship between pernicious anaemia, achlorhydria, atrophic gastritis and gastric carcinoid is discussed. The gastric neuroendocrine tumours and their structural and functional characteristics were reviewed in an attempt to clarify the nomenclature and the diagnostic and therapeutic approach in these situations.

Adult↗
PubMed1989

[The heart and diabetes. An anatomo-clinical study].

We performed a retrospective study in 72 autopsies of diabetic patients (DMP) selected out of 2,239 adult autopsies, comprehending the period between 1966 to 1982. In order to analyse the possible Diabetic Cardiomyopathy, the DMP were divided into 8 groups according to the presence or the absence of Myocardial Fibrosis (MF) and Congestive Heart Failure (CHF). The Diabetes Mellitus (DM) incidence according to the race, sex, age and the presence of Kimmestiel-Wilson (KW) were in agreement with the literature data. The majority of the deaths occurred after the sixth-decade and we did not find any DMP with Malignant Hypertension. Hypertension and Coronary Artery Disease (CAD) increased the frequency of anatomical cardiac alterations, as follows: 1. MF was more associated with CAD, 2. Hypertension was more frequent in DMP with KW in the nodular form; 3. Hypertension increased the frequency of left ventricular hypertrophy; 4. Myocardial Infarction occurred in the absence of occlusive vascular phenomena. The Myocardial Fibrosis (MF) observed in DMP without ACD and without hypertension may be final anatomic demonstration of a gradual metabolic-functional process, and not the basic mechanism of the CHF in the possible Diabetic Cardiomyopathy.

Adolescent↗