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J A Marques

Publications and source records attributed to J A Marques.

15 recordsLinked to original sources
PubMed2001

Congenital inclusion cysts of the anterior fontanelle.

BACKGROUND: Congenital inclusion cysts of the anterior fontanelle are rare lesions. Both dermoid and epidermoid cysts are located in the midline of the scalp and occupy the subgaleal space. METHODS: We report 7 cases, 4 boys (57.1%), and 3 girls (42.9%), with ages ranging from 3 months to 16 years (mean 40.85 +/- 68.56 months; median 10 months). Four patients (57.1%) were white and 3 (42.9%) were Afro-Brazilian. RESULTS: The cysts had manifested soon after birth in all patients. They gradually enlarged, with no intracranial extensions. Four patients had dermoid cysts and the others had epidermoid cysts. All of them underwent surgery with complete excision of the cyst and no capsular rupture. There were no complications and no deaths. CONCLUSIONS: Congenital inclusion cysts of the anterior fontanelle are rare lesions that usually manifest at birth. The diagnosis is usually easy and surgery is mandatory, with a good prognosis. Recurrence is rare.

Adolescent↗
PubMed2001

A barbourin-albumin fusion protein that is slowly cleared in vivo retains the ability to inhibit platelet aggregation in vitro.

Barbourin is a 73 amino acid venom protein that inhibits platelet aggregation. Recombinant barbourin (BARH6), rabbit serum albumin (RSAH6), and a barbourin-RSA fusion protein (barbourin-linker-albumin; BLAH6) were secreted from Pichia pastoris yeast, and purified by nickel-chelate affinity chromatography via their C-terminal hexahistidine (H6) tags. BARH6 and BLAH6 did not differ in their IC50s for inhibition of platelet aggregation using either human platelets stimulated with thrombin or ADP, or rabbit platelets stimulated with ADP. BARH6 and BLAH6 were also effective in inhibiting platelet aggregation in whole blood, and formed complexes with platelet integrin alphaIIbbeta3. The terminal catabolic half-life of BLAH6 approached that of RSAH6 [3.4 +/- 0.2 versus 4.0 +/- 0.1 days (n = 4 +/- SD)], but was substantially increased relative to that of BARH6 [0.15 +/- 0.03 days (n = 3 +/- SD)]. Our results suggest that fusion to albumin slows the clearance of barbourin in vivo, while preserving its ability to inhibit platelet aggregation.

Adenosine Diphosphate↗
PubMed2000

Modulation of clearance of recombinant serum albumin by either glycosylation or truncation.

Albumin is an abundant non-glycosylated plasma protein with a slow clearance profile. It has been employed as a fusion partner in efforts to slow the clearance of small antithrombotic proteins like hirudin. In the present study, the in vivo clearance of recombinant rabbit serum albumin (rRSA), of mutant rRSAs containing consensus sequences for N-linked glycosylation (D494N and V14T variants), and of mutant mini-proteins truncated at albumin domain boundaries (rRSAs 1-185, 1-377, or 378-584) was examined. Mean terminal catabolic half-lives (t(0.5)cat) in rabbits for plasma-derived RSA, rRSA, and the V14T variant did not differ significantly (range 4. 32-4.76 days). In contrast, mean t(0.5)cat was reduced to 2.87 days for the D494N variant and to less than 0.071 days for all mini-proteins. The mini-proteins were found in the urine in tissue distribution experiments, suggesting a renal route of clearance. Our results suggest that all three internally repeated albumin domains are required to maintain the slow in vivo clearance profile of albumin, and that albumin glycosylation can be associated with an acceleration of clearance. This information could be used to design fusion proteins, including those with antithrombotic properties, with predictably altered in vivo half-lives less than that of serum albumin.

Animals↗
PubMed2000

[Carotid body tumors: review of 8 cases and surgical approach].

Carotid body tumors are rather uncommon. Even though there is a great amount of literature on the subject, the controversy regarding its biological behavior and therapeutics and mainly, the surgical management still remains. We present eight patients with carotid body tumors (total of 9 tumors, one bilateral) surgically treated at the Neurosurgery Department of Santa Casa in Belo Horizonte, from 1989 to 1999. The age ranged from 11 to 66-years-old (35,6+/-17.7). Four patients were women and four were men. We had satisfactory postoperative results with low morbidity and no deaths. Based on our experience and on the review of the literature, some aspects of this disease are discussed. We conclude that carotid body tumors are uncommon and should be treat with carefully surgery techniques to obtain low morbi-mortality rates.

Adolescent↗
PubMed2000

[Lipoma of the cerebellopontine angle: case report].

Lipoma of the cerebellopontine angle is a very rare tumor. We report the case of a 14-years-old female, with left side deafness during three years, associated with headache. CT scan showed an hypodense mass, without enhancement at the cerebellopontine angle. The patient was treated surgically by left retrosigmoid approach. The lesion involved the eighth and seventh cranial nerves and only a partial removal was performed. The postoperative course was uneventful. She had no more headache; the deafness of the left side remained unchanged. Asymptomatic lipoma of the cerebellopontine angle can be treated conservatively, although those with progressive symptoms should be treated surgically, with total or partial remove based on their neurovascular involvement.

Adolescent↗
PubMed2000

[Cavernoma of the lateral ventricle: case report].

UNLABELLED: Cavernous malformations are uncommon lesions that are usually present in the cerebral hemispheres. They occur rarely in the ventricular system, and even more rarely in the lateral ventricle. Only 28 cases have been previously reported in the literature. CASE: We present one case of lateral ventricle cavernoma in a 15-years-old female patient, who suffered of mild chronic headache for 8 months, followed by two episodes of sudden intensive headache and stupor with complete recovery after 48 hours. CT scan was performed and revealed a voluminous size, hiperdense mass in the frontal horn of the lateral ventricle. The surgical access to site was through transcallosal interhemisphere approach. The patient had a good recovery without complications. CONCLUSION: Although lateral ventricle cavernomas are rare they should be considered in the differential diagnosis of intraventricular tumors. A wrong preoperative diagnosis has sometimes induced a wrong therapy, such as radiotherapy, for these surgically curable benign lesions.

Adolescent↗
PubMed1997

Gastroduodenal resistance and neural mechanisms involved in saline flow decrease elicited by acute blood volume expansion in anesthetized rats.

We have previously demonstrated that blood volume (BV) expansion decreases saline flow through the gastroduodenal (GD) segment in anesthetized rats (Xavier-Neto J, dos Santos AA & Rola FH (1990) Gut, 31: 1006-1010). The present study attempts to identify the site(s) of resistance and neural mechanisms involved in this phenomenon. Male Wistar rats (N = 97, 200-300 g) were surgically manipulated to create four gut circuits: GD, gastric, pyloric and duodenal. These circuits were perfused under barostatically controlled pressure (4 cmH2O). Steady-state changes in flow were taken to reflect modifications in circuit resistances during three periods of time: normovolemic control (20 min), expansion (10-15 min), and expanded (30 min). Perfusion flow rates did not change in normovolemic control animals over a period of 60 min. BV expansion (Ringer bicarbonate, 1 ml/min up to 5% body weight) significantly (P < 0.05) reduced perfusion flow in the GD (10.3 +/- 0.5 to 7.6 +/- 0.6 ml/min), pyloric (9.0 +/- 0.6 to 5.6 +/- 1.2 ml/min) and duodenal (10.8 +/- 0.4 to 9.0 +/- 0.6 ml/min) circuits, but not in the gastric circuit (11.9 +/- 0.4 to 10.4 +/- 0.6 ml/min). Prazosin (1 mg/kg) and yohimbine (3 mg/kg) prevented the expansion effect on the duodenal but not on the pyloric circuit. Bilateral cervical vagotomy prevented the expansion effect on the pylorus during the expansion but not during the expanded period and had no effect on the duodenum. Atropine (0.5 mg/kg), hexamethonium (10 mg/kg) and propranolol (2 mg/kg) were ineffective on both circuits. These results indicate that 1) BV expansion increases the GD resistance to liquid flow, 2) pylorus and duodenum are important sites of resistance, and, 3) yohimbine and prazosin prevented the increase in duodenal resistance and vagotomy prevented it partially in the pylorus.

Animals↗
PubMed1996

Acute effects of inhaled and i.v. cocaine on airway dynamics.

BACKGROUND: Wheezing has been reported by 32% of habitual smokers of crack cocaine, and several cases of crack-related acute exacerbations of asthma have been reported. STUDY OBJECTIVE: To compare the acute effects of physiologically active doses of smoked cocaine base and, i.v. cocaine hydrochloride (HCl), a subphysiologic dose of cocaine base (smoked "placebo"), and i.v. saline solution placebo on bronchomotor tone, subjective level of intoxication, and cardiovascular responses in healthy habitual crack users. DESIGN: A single-blind crossover study in which the order of route of administration (inhaled vs i.v.) was random but placebo always preceded the active drug. SUBJECTS: Fourteen healthy, nonasthmatic current crack-smoking subjects, 34 to 48 years of age, with a history of previous i.v. cocaine use (1 to 12 times per lifetime). METHODS: Heart rate, BP, self-rated level of intoxication (scale of 0 to 10), and measurements of airway resistance (Raw) and specific airway conductance (SGaw) were recorded during separate sessions before and 3 to 5, 10, 15, and 30 min after administration of smoked cocaine base (38.5 +/- 2.3 [SEM] mg), smoked placebo (2.3 +/- 0.9 mg cocaine base), i.v. cocaine HCl (30.0 +/- 2.0 mg), and i.v placebo (saline solution). RESULTS: Both smoked active cocaine and i.v. cocaine HCl caused comparable, significant (p < 0.05) peak levels of acute intoxication (6.7 +/- 0.7 and 7.3 +/- 0.8, respectively) and increases in heart rate from baseline (29.6 +/- 2.9% and 21.4 +/- 3.7%, respectively, at 5 min). However, only smoked active cocaine caused significant decreases from baseline in SGaw (25.4 +/- 6.3% at 5 min), in contrast to nonsignificant changes after i.v. cocaine HCl (5.6 +/- 7.0% increase) and smoked placebo (10.2 +/- 6.0% decrease). CONCLUSIONS: Smoked cocaine base, but not systemically administered cocaine HCl, causes acute bronchoconstriction that is probably mediated by local airway irritation and could account for reports of crack-induced wheezing and asthma attacks in nonasthmatic and asthmatic individuals, respectively.

Administration, Inhalation↗
PubMed1994

[Prevalence of asthma in the city of Porto].

It is possible that asthma epidemiology will contribute to the definition of asthma precipitant factors. This work is enrolled in an international study co-ordinated by COMAC-EPI. In Oporto, among 137.000 residents in the same town region, a standardised sample of 4.047 male and female individuals aged from 20 to 44 years was defined. A screening questionnaire was sent with a stamped envelope. Four months later the same questionnaire was sent to the individuals who did not answer it and finally those who do not answer the second letter were visited in their own residence. We got 2075 answers. Among the responders about half were women: 1075, 25.39% belonging (273) to the 20-29 years age group; 42.69% (459) 30-39 years; 31.90% (343) 40-44 years. In men the percentage of distribution by age groups was similar. Question nQ 5 was answered affirmatively by 60 individuals, corresponding to the prevalence of 2.89%. Seventy-one (3.42%) said they had been under asthma treatment during the last year. Among the symptoms that usually define the attack of asthma, those inquired in the group of question 1 show a prevalence close to that of the asthma diagnosis: 6.45%. The prevalence of being awakened by tightness in the chest, shortness of breath and coughing, with values of 16.17%, 10.69% and 25.68% is quite superior than in question nQ 5. The prevalence obtained with the Hay Fever question was 18.84%. Data obtained is similar to the data of other centers.

Adult↗
PubMedDate not supplied

Treatment of carcinoma in situ of the cervix experience at the Faculty of Medicine, University of São Paulo.

The authors studied a total of 334 cases of carcinoma in situ of the cervix (1975-1990). The patients were 19 to 61 years old (mean age, 36.6 years). The following procedures were performed: cervical amputation in 54.5% of cases, cervical enlarged amputation with resection of the adjacent vaginal mucosa in 23.3%, abdominal hysterectomy in 15.3%, electrocauterization in 3.6%, simple conization in 2.4%, and vaginal hysterectomy in 0.9%. Recurrence rates were: 9.8% after cervical amputation, 1.3% after cervical enlarged amputation, 25% after simple conization, 5.8% after abdominal hysterectomy, and 33% after electrocauterization. Recurrences were detected before the 18th month after treatment and none of them was of the invasive type. The treatment procedure with the highest rate of complications was cervical enlarged amputation (16%), followed by simple conization (12%), total abdominal hysterectomy (3.9%), and cervical amputation (2.9%). The authors conclude that, although cervical enlarged amputation was followed by the lowest recurrence rate, it was also the treatment followed by the largest number of complications. On this basis, they recommend cervical amputation or hysterectomy. For young women who wish to have children, simple conization is recommended.

Adult↗
PubMedDate not supplied

[Inter- and intra-observer variation in silicosis radiology].

The radiologic criteria are important for the diagnosis of silicosis and must be objective. Initial radiologic changes are nonspecific and sometimes misinterpreted. We asked six Pulmonologists with distinct training in pulmonary disease to interpret 112 chest films according to a simple established protocol. No further information was given. One year later, all the observers analysed the same films over again. Then, we compared the results among the observers and between the two analysis made by the same individual. In 34 cases (30%) there was unanimity in asserting or denying the presence of micronodules and in 74 cases (66%) there was an agreement among the three more experienced observers. The intraobserver variability ranged from 8% to 40% and it was more important in the least trained observers. We concluded that when interpreting early radiologic changes in silicosis inter and intraobserver variability was elevated, more objectivity was achieved by the observers with more experience in epidemiologic studies and that we must be careful in interpreting results of epidemiologic studies concerning this matter.

Adult↗