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Biomedical subjects

J C Andrade

Publications and source records attributed to J C Andrade.

At least 19 recordsLinked to original sources
PubMed2005

Production of 1,3-Propanediol by Clostridium butyricum VPI 3266 in continuous cultures with high yield and productivity.

The effects of dilution rate and substrate feed concentration on continuous glycerol fermentation by Clostridium butyricum VPI 3266, a natural 1,3-propanediol producer, were evaluated in this work. A high and constant 1,3-propanediol yield (around 0.65 mol/mol), close to the theoretical value, was obtained irrespective of substrate feed concentration or dilution rate. Improvement of 1,3-propanediol volumetric productivity was achieved by increasing the dilution rate, at a fixed feed substrate concentration of 30, 60 or 70 g l(-1). Higher 1,3-propanediol final concentrations and volumetric productivities were also obtained when glycerol feed concentration was increased from 30 to 60 g l(-1), at D=0.05-0.3 h(-1), and from 60-70 g l(-1), at D=0.05 and 0.1 h(-1).30 g l(-1) of 1,3-propanediol and the highest reported value of productivity, 10.3 g l(-1) h(-1), was achieved at D=0.30 h(-1) and 60 g l(-1) of feed glycerol. A switch to an acetate/butyrate ratio higher than one was observed for 60 g l(-1) of feed glycerol and a dilution rate higher than 0.10 h(-1); moreover, at D=0.30 h(-1) 3-hydroxypropionaldehyde accumulation was observed for the first time in the fermentation broth of C. butyricum.

Acetates↗
PubMed2004

Production of 1,3-propanediol by Clostridium butyricum VPI 3266 using a synthetic medium and raw glycerol.

Growth inhibition of Clostridium butyricum VPI 3266 by raw glycerol, obtained from the biodiesel production process, was evaluated. C. butyricum presents the same tolerance to raw and to commercial glycerol, when both are of similar grade, i.e. above 87% (w/v). A 39% increase of growth inhibition was observed in the presence of 100 g l(-1) of a lower grade raw glycerol (65% w/v). Furthermore, 1,3-propanediol production from two raw glycerol types (65% w/v and 92% w/v), without any prior purification, was observed in batch and continuous cultures, on a synthetic medium. No significant differences were found in C. butyricum fermentation patterns on raw and commercial glycerol as the sole carbon source. In every case, 1,3-propanediol yield was around 0.60 mol/mol glycerol consumed.

Clostridium butyricum↗
PubMed1998

Importance of intraoperative transesophageal echocardiography during coronary artery surgery without cardiopulmonary bypass.

The goal of this study was to assess left ventricular segmental wall motion (SWM) abnormalities during coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB), and its impact on the immediate postoperative outcome. Transesophageal echocardiography was used intraoperatively in 27 patients (mean age 57 years) who had CABG without CPB. Images obtained with a 5-MHz biplane transesophageal echocardiographic probe in the transgastric and transesophageal planes were recorded before, during, and after 48 coronary artery clampings for saphenous vein or internal mammary artery anastomosis. Transthoracic echocardiography was performed 1 day before surgery and on the seventh postoperative day. During the 48 coronary artery clampings, 31 (64%) new SWM abnormalities were found. At the time of chest closure, complete recovery occurred in 16 (50%) segments, partial recovery in 10 (33%), and no recovery in 5 (17%). On the seventh postoperative day the new SWM abnormalities persisted in all 5 segments without recovery at the end of the surgery and in 2 of 10 (20%)segments with partial recovery (group 1). Group 1 had higher variation on the echocardiographic point score index between the beginning and end of surgery, higher enzymatic levels, more ST-T changes on the electrocardiogram, and more clinical problems than group 2 (patients without new SWM abnormalities on the seventh postoperative day) (P < .05). We concluded that new SWM abnormalities of the left ventricle occur during CABG without CPB as assessed by intraoperative transesophageal echocardiography. Persistence of these abnormalities at the end of surgery may be a predictor of SWM dysfunction and clinical problems in the immediate postoperative period.

Adult↗
PubMed1998

On the incidence of the biceps brachii third head in Brazilian white and blacks.

The incidence of a third head of the biceps brachii muscle has been reported in several articles, and there is a general idea that it is a race-dependent variation. The aim of this investigation was to study the biceps brachii muscle with regard to the incidence of its third head in a mixed white and black Brazilian population. A total of 200 upper arms from adult white and black cadavers (100 whites and 100 blacks) fixed in a 10% formol solution were examined and compared. It was observed that for white subjects the incidence of the third head was 20% against 9% for the black subjects: a statistically significant difference. We suggest that other factors, in addition to racial ones, might play a part in determining the incidence of the biceps brachii third head in a population.

Adult↗
PubMed1998

Mitral valve replacement with glutaraldehyde preserved aortic allografts.

OBJECTIVE: To present long-term results after mitral valve replacement with stent mounted glutaraldehyde preserved aortic allografts in patients older than 15 years. The clinical support for this study was to combine the glutaraldehyde technique of biological tissue preservation with the advantages of allografts when compared to xenografts. This was demonstrated in previous studies using other methods of tissue processing. METHODS: Between September 1984 and November 1994, 70 patients aged 16-77 years (mean 35.4 years) underwent mitral valve replacement with this preserved and mounted allograft. Of these, 40 patients (57.2%) were aged 16-35 years and 15 (21.4%) were 20 years old or younger; 46 (65.7%) were females and 24 (34.3%) males. Single mitral valve replacement was performed in 60 patients and 10 were also subjected to other combined cardiac procedures. Human aortic valves were obtained during routine autopsy, processed in glutaraldehyde and mounted into flexible stents, using the same technique as that used for porcine bioprostheses. RESULTS: Hospital mortality was 1.4%. Total follow-up was 543.1 patient-years, corresponding to a mean follow-up of 7.9 years per patient. Echocardiography demonstrated a hemodynamic performance similar to porcine bioprostheses. Late mortality was 0.7 +/- 0.6% per patient-year and the causes were congestive heart failure in 2, prosthetic endocarditis in 1 and acute myocardial infarction in 1. The 12-year actuarial survival was 92.4 +/- 3.2%. The incidence of late complications was 5.2 +/- 1.2% per patient-year, including congestive heart failure, prosthetic endocarditis, periprosthetic leak, thromboembolic episodes, recurrence of rheumatic disease, coronary artery disease and allograft failure. Complications related to heart disease represented 2.8 +/- 0.6% and allobioprosthesis-related 2.4 +/- 0.5% per patient-year. The 12-year actuarial freedom from primary valve failure was 81.0 +/- 15.0%. The incidence of reoperations was 1.5 +/- 0.8% per patient-year and the main indication was prosthetic endocarditis. Other causes were periprosthetic leak, aortic insufficiency in the native aortic valve and allobioprosthesis dysfunction. Functional results demonstrated a significant improvement in patients clinical condition. CONCLUSION: This 12-year follow-up shows a very low incidence of primary allograft failure for patients older than 15 years undergoing mitral valve replacement, and much superior than our results with porcine bioprosthesis in the same age group. This supports our assumption that this investigational valve represents a new advance in cardiac valve surgery.

Adolescent↗
PubMed1997

Surgical treatment of acute type B aortic dissection using an endoprosthesis (elephant trunk).

BACKGROUND: The surgical treatment of acute complicated type B aortic dissection continues to be a challenge and is still associated with high morbidity and mortality rates. METHODS: Seventy consecutive patients with an acute type B aortic dissection underwent an elephant trunk procedure through a median sternotomy during deep hypothermic circulatory arrest. An endoprosthesis that was 22 to 24 mm in diameter was inserted through an incision in the arch and held in place with only proximal sutures. RESULTS: The mean arrest time was 31.4 +/- 8.7 minutes, and it was possible to adequately position the endoluminal graft in every patient. The procedure was done in association with other procedures in 13 patients. There were six in-hospital deaths not related to the endoprosthesis, and four late deaths. Late reoperation was necessary in 6 patients to manage leakage at the proximal suture line. CONCLUSIONS: The insertion of an endoprosthesis through the arch for the management of a complicated acute type B dissection has several advantages over the conventional thoracotomy approach. The hospital mortality rate in this series of 70 patients was 20%, and the actuarial 5-year survival rate was 62.5%. We consider the elephant trunk procedure the treatment of choice in patients with type B acute dissections, regardless of whether the dissection is complicated or not.

Adult↗
PubMed1996

Transaortic approach has a role in the surgical treatment of ventricular septal defects.

A transaortic approach was used for surgical closure of ventricular septal defects (VSDs), sometimes as first choice and otherwise as an alternative approach. This paper presents the experience in a group of 124 patients who underwent VSD closure by a transaortic approach in an 18-year-period, between 1974 and 1992. Patients were divided in three groups: (I) Isolated VSD, 89 patients (mean age 7.6 years); (II) VSD associated with other malformations, 27 patients (mean age 10.8 years); and (III) recurrent VSD, eight patients (mean age 15.6 years). Two deaths occurred in the postoperative period (2/124), one after closure of VSD in a patient with severe pulmonary hypertension; another death was observed after transaortic closure of the VSD as part of the repair of a complex heart malformation. There were no instances of new right bundle branch block (RBBB) in the group operated on for isolated VSDs. Three cases of left bundle branch block (LBBB) (3.4%) occurred in the isolated VSD group. There were no cases of complete aortic valve (AV) block in the whole series and no instances of AV dysfunction. The transaortic approach is an alternative for the surgical treatment of ventricular septal defects. The ease of exposure and closure of defects suggest this technique to be a particularly attractive approach in the treatment of small to moderate-sized VSDs and also in recurrent VSDs.

Adolescent↗
PubMed1994

[Late development of congestive heart failure in interventricular communication caused by penetrating wound, with pulmonary hypertension resolution after surgical correction].

Male, 33 years-old, with onset of heart failure and edema; he used to be completely asymptomatic but mentioned he underwent previously a pleural drainage, after a hemothorax provoked by a stab wound. His physical examination confirmed he was in heart failure and showed a harsh holosystolic murmur between mitral and tricuspid areas. Cardiac catheterization demonstrated a large apical ventricular septal defect (VSD) and systemic pulmonary arterial pressures. With oxygen there was an increase in the left to right shunt and normal pulmonary vascular resistance. The clinical diagnosis was that of a traumatic VSD provoking pulmonary hypertension although a congenital etiology could not be completely ruled out. At surgery there was a sharp cut at the pericardium and an apical epicardial lesion; the VSD was patch sutured and the patient did well with control of his heart failure. A control hemodynamic study performed within the first postoperative month showed no residual shunt and complete normalization of the pulmonary pressures and resistance.

Adult↗
PubMed1994

[Myocardial revascularization without extracorporeal circulation. Surgical results in 1090 patients].

PURPOSE: To report our experience of 12 years of myocardial revascularization without cardiopulmonary bypass (CPB) and to discuss its expanding surgical indications. METHODS: This technique was employed in 1090 patients, between September/81 and April/93, corresponding to 17.4% of all revascularized patients. Regarding gender, male patients were the majority (73.7%) and ages ranged from 28 to 86 year-old (mean 57). Chronic coronary insufficiency was the main indication (69.4%) and 18.9% of our global experience were operated on during acute ischemia. The average number of grafts per patient was 1.6 and internal mammary artery was utilized in 60.1% of patients. Left anterior descending coronary artery and right coronary artery were the coronary arteries most often treated. RESULTS: Our hospital mortality rate was 2.5% (28/1090) although it was 7% for patients over 70 years. The most common cause of death was cardiogenic shock after failed angioplasty. Postoperative complications included AMI in 4.8%, arrhythmias in 5.5% and pulmonary in 3.2%. Mean of any type of blood derivate utilization was 0.28 units/patients. CONCLUSION: Myocardial revascularization without CPB is a valid alternative in a selected cohort of patients and it is performed with low morbidity and mortality. Nowadays it represents an excellent tactical option for high-risk patients and in failed angioplasties.

Adult↗
PubMed1993

[Hemodynamic study with Swan-Ganz catheterization, concomitant to endomyocardial biopsy in heart transplantation patients. Importance in the early diagnosis of rejection].

PURPOSE: To evaluate the role of hemodynamic parameters in the diagnosis of acute rejection who underwent orthotopic cardiac transplantation. METHODS: A protocol was carried out in 19 patients who underwent heart transplantation and in whom Swan-Ganz hemodynamics was performed immediately prior to routine endomyocardial biopsy in the first few months postoperatively. The results of 28 biopsies were divided in group I--severe rejection who needed pulse-therapy (n = 10) and group II--No or mild/moderate rejection who did not need any pulse (n = 18). Hemodynamic parameters were compared between both groups. RESULTS: There were significant differences among hemodynamic parameters in groups I and II. Group I had higher mean right atrial pressures (13.0 x 7.3 mmHg), mean pulmonary pressure (26.3 x 20.4 mmHg), mean wedge pressure (14.4 x 10.9 mmHg) and lower cardiac index (2.57 x 3.10 l/min/m2). CONCLUSION: In a routine situation, hemodynamic measurements, as obtained with Swan-Ganz catheter, simultaneously with endomyocardial biopsies, show significant alterations in transplanted patients who develop acute rejection. This information, obtained earlier than the biopsy results, could shorten the time to initiate pulse-therapy in patients with severe rejection.

Adult↗
PubMed1992

[Early and late results of myocardial revascularization after coronary thrombolysis with intravenous streptokinase in the treatment of acute myocardial infarction].

PURPOSE: To study the early and late results of patients treated initially intravenous streptokinase and then with coronary artery bypass surgery. METHODS: One hundred and twenty one patients with acute myocardial infarction less than 6 hours duration were treated initially with intravenous streptokinase, and 1-38 days after (median 8.80 days) coronary artery bypass was undertaken. Ninety six patients were operated with extracorporeal circulation and 25 without it. RESULTS: Overall operative mortality was 3.30% (4/121). Reoperations due to bleeding was necessary in 3.30% (4/121). Late mortality was 5.40% with survival probability of 94.60% after 36 months and 92.30% after 70 months. Late morbidity events in terms of angina and cardiac insufficiency demonstrated that 7 patients had angina, 4 cardiac insufficiency and two angina and cardiac insufficiency; probability to be free from these events was 88.20% after 46 months and 66.40% after 70 months. CONCLUSION: Coronary artery bypass surgery after intravenous streptokinase can be undertaken with security and excellent early and late results.

Adult↗
PubMed1991

[Systemic-pulmonary shunts in congenital heart diseases with decreased pulmonary blood flow: critical analysis of the surgical techniques and immediate results].

PURPOSE: To evaluate immediate postoperative results in children with congenital heart disease and decreased pulmonary blood flow who underwent a systemic to pulmonary shunt. PATIENTS AND METHODS: Sixty-four patients underwent surgery, 46.8% (30) of them males with ages from 1 day to 17 years old. They were divided in three groups: I--13 pts (20.3%) who underwent classical Blalock-Taussig (BT) shunt; II--46 pts (71.8%) who underwent modified BT shunts, 34 of them with polytetrafluoroetylene (PTFE) and 12 of them with umbilical vein shunts; III--5 pts (7.8%) with central anastomosis that were made with three different types of graft; 3 PTFE, umbilical vein and bovine mammary artery in one each. The simultaneous procedures were: section and suture of PDA--2, closure of systemic-pulmonary collaterals--3, pulmonary valvotomy--3, right ventricular outflow patch--3, pulmonary branch stenosis (enlargement)--2. RESULTS: In group I there were 4 (30.7%) closures, with two immediate reoperation and a total mortality of 30.7%. In group II there were 4 closures (8.6%) and two reoperations with a mortality of 15.2% (7 cases). In group III there was one graft closure and an overall mortality of 80% (4 pts). When analysing deaths due to the shunt itself the mortality rate was respectively 15.3%, 8.6% and 40.0%. CONCLUSION: Modified BT operation was performed most frequently in our service; it was associated with less closure and mortality than the other types of shunt. It is considered our first alternative for a systemic-pulmonary shunt.

Adolescent↗
PubMed1990

Myocardial revascularization without extracorporeal circulation. Seven-year experience in 593 cases.

The authors present the results of 593 consecutive and non-selected patients who underwent direct myocardial revascularization without extracorporeal circulation in the period September 1981 to December 1988. The results are compared with 3086 patients who underwent conventional bypass surgery over the same period of time. The ages varied from 33 to 80 years (mean = 56) with 40 patients older than 70. The overall mortality in the group without cardiopulmonary bypass (CPB) was 1.7% (10/593) compared with 3.8% for conventional revascularization. Our mortality in the last 3 years has been 0.5% and 0% in the last 203 patients revascularized without CPB. The number of grafts varied from 1 to 5 (average 1.6). The treated arteries were: anterior descending (557), right (282) marginal (5) and circumflex marginal (4). Immediate postoperative complications were fewer and hospital discharge was earlier in the group treated without CPB. The authors conclude that this tactical alternative has the advantages of: lower morbidity and mortality, lower cost and no need for blood transfusion. Drawbacks are the need for greater technical expertise and it seems to be possible in about 19% of all patients who undergo myocardial revascularization.

Adult↗
PubMed1990

Cardiac valve replacement with glutaraldehyde preserved aortic allografts.

From September 1984 to December 1988, 144 patients underwent cardiac valve replacement using glutaraldehyde preserved stent mounted aortic allografts. The mean age was 21.4 years (54.9% were 15 years old or younger). The mitral valve was replaced in 125 patients, the aortic valve in 7, the pulmonary valve in 3, the tricuspid in 1, the mitral and tricuspid in 1, and the aortic and mitral in 7. Hospital mortality was 2.8% (4 patients). Total follow-up was 396.3 patient-years and the mean follow-up was 2.8 years per patient. The 5-year actuarial survival was 73.8% +/- 11.9%. The 4-year actuarial survival for patients aged 15 or younger was 81.4% +/- 7.1%. The overall mortality was 2.8% +/- 0.8%/per patient-year. The incidence of valve-related complications was 4.8% +/- 1.1%/per patient-year, and the calcification rate was 3.0% +/- 0.9%/per patient-year and was the main complication reported in 12 patients, all under the age of 15 years. It occurred 14-47 months after implantation (mean 32.7 months). Five-year actuarial freedom from valve dysfunction due to calcification was 82.6% +/- 5.0% and for patients aged 15 or younger was 69.9% +/- 8.8%. The incidence of reoperation was 3.3% +/- 0.9%/per patient-year. These initial results demonstrate a 5-year actuarial freedom from primary valve failure due to fibrocalcification superior to the results obtained with xenobioprostheses in the paediatric age group.

Actuarial Analysis↗