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J C Trindade

Publications and source records attributed to J C Trindade.

At least 19 recordsLinked to original sources
PubMed2001

Single-cell gel (comet) assay detects primary DNA damage in nonneoplastic urothelial cells of smokers and ex-smokers.

A protocol for DNA damage assessment by the single-cell gel (SCG)/comet assay in human urinary bladder washing cells was established. Modifications of the standard alkaline protocol included an increase to 2% of sodium sarcosinate in the lysis solution, a reduction in the glass-slide area for comet analysis, and a cutoff value for comet head diameter of at least 30 microm, to exclude contaminating leukocytes. Distinguishing cell populations is crucial, because significant differential migration was demonstrated for transitional and nontransitional cells, phenomena that may confound the results. When applying the modified protocol to urinary bladder cells from smokers without urinary bladder neoplasia, it was possible to detect a significant (P = 0.03) increase in DNA damage as depicted by the tail moment (6.39 +/- 3.23; mean +/- 95% confidence interval; n = 18) when compared with nonsmokers (1.94 +/- 1.41; n = 12). No significant differences were observed between ex-smokers and current smokers regarding comet parameters. Inflammation was not a confounding factor, but DNA migration increased significantly with age in nonsmokers (r = 0.68; P = 0.014). Thus, age matching should be a concern when transitional cells are analyzed in the SCG assay. As it is well known, DNA damage may trigger genomic instability, a crucial step in carcinogenesis. Therefore, the present data directly support the classification of individuals with smoking history as patients at high risk for urinary bladder cancer.

Adult↗
PubMed1996

[Urinary flow in children: correlation with age, body height and body surface area].

Peak flow rate data (Qmax) are important for diagnosis of lower urinary tract obstruction. However, the lack of uroflowmetry studies in children, makes their interpretation difficult. With this aim, we studied 167 boys classified in four groups according to their age (G1: n = 48, 6-7 years; G2: n = 43, 8-9 years; G3: n = 37, 10-11 years; G4: n = 39, 12-14 years). We studied in all children, weight, height, body surface area, peak flow rate (Qmax) and the correspondant urinary volume (Vol). Means and standard deviations of Qmax (ml/sec) were: 15 +/- 5 (G1), 15 +/- 5 (G2), 17 +/- 5 (G3) and 22 +/- 7 (G4) respectively. Corresponding urinary volumes (Vol) (mean standard deviation-in ml) were: G1 = 123 +/- 75; G2 = 122 +/- 79; G3 = 158 +/- 96 and G4 = 162 +/- 101. We found a significant correlation (p < 0,01) between Qmax and Vol in groups G2, G3 and G4; and between Qmax and height in groups G1 and G4. The authors demonstrated a positive correlation between maximum flow and voided volume, and an increase of Qmax with age.

Adolescent↗
PubMed1994

Two end-to-side neurorrhaphies and nerve graft with removal of the epineural sheath: experimental study in rats.

We have studied a new type of end-to-side nerve repair in rats. The healthy (donor) nerve was not divided but an epineural window was created. In our experiment, a nerve graft bridged the tibial nerve to the distal end of the divided peroneal nerve. Electrophysiological studies showed electrical impulses conducted through both end-to-side nerve junctions. Histological studies demonstrated axons leaving the lateral surface of the healthy (donor) nerve. Based on these observations, we suggest that end-to-side neurorrhaphy from a healthy nerve may bridge a neural deficit.

Anastomosis, Surgical↗
PubMed1994

End-to-side neurorrhaphy with removal of the epineurial sheath: an experimental study in rats.

Terminolateral neurorrhaphies were used up to the beginning of this century. After that, they were no longer reported. We tested the efficacy of a new type of end-to-side neurorrhaphy. A group of 20 rats had the peroneal nerve sectioned, and the distal ending was sutured to the lateral face of the tibial nerve after removing a small epineural window. All experiments were made on the right side, the left one remaining untouched in half the animals of each group. The other half was denervated by sectioning and inverting the endings of the peroneal nerves. In this way, tibial cranial muscles were either normal or denervated on the left side and reinnervated through end-to-side neurorrhaphies on the right side. After 7.8 months, the animals were subjected to electrophysiologic tests, sacrificed, and the nerves and muscles were taken for histologic examination. A response of the tibial cranial muscle was obtained in 90 percent of the animals. The distal ending of the peroneal nerve showed an average of 861 nerve fibers. The average areas of the reinnervated tibial cranial muscles were (microns 2) 1617.81 for M2n (when the contralateral side was normal) and 1579.19 for M2d (when the contralateral was denervated). We conclude that the terminolateral neurorrhaphy is functional, conducting electrical stimuli and allowing the passage of axons from the lateral surface of a healthy nerve, to reconstitute the distal segment of a sectioned nerve. The absence of an incision on the axons of the donor nerve was no impediment to axonal regeneration or to the passage of electrical stimuli. The results demonstrate the possibility of using end-to-side and terminolateral neurorrhaphies for reconstituting neural lesions when only a distal end is available; the reinnervation can be obtained from the lateral face of a healthy nerve.

Animals↗
PubMed1990

Influence of nephrectomy on the growth of a murine Wilms tumor: a study using parabiotic rats.

It has been reported that unilateral nephrectomy causes acceleration of the growth of a Wistar/Furth rat Wilms tumor. We studied this phenomenon in parabiotic rats by measuring tumor growth after either sham nephrectomy, or excision of 1, 2 or 3 kidneys. We observed no stimulation of tumor growth in the experimental groups. Renal function was significantly decreased after removal of 2 or 3 kidneys. Serum creatinine levels were significantly different between right and left members of parabiotic pairs in these 2 groups. The effect of unilateral and bilateral nephrectomy on tumor growth in single rats also was examined. In these rats progressive increases in tumor growth were observed after unilateral and bilateral nephrectomy. Our inability to demonstrate a tumor-stimulating factor in the parabiotic model may be due partly to incomplete sharing of humoral factors between parabionts. Serum transfer studies in vitro may prove more fruitful in demonstrating such a factor.

Animals↗
PubMed1985

Cyclophosphamide and inhibition of renal compensatory hypertrophy.

The objective of the present study was to determine whether cyclophosphamide inhibits nephrectomy-induced compensatory renal hypertrophy directly or indirectly owing to the reduced food intake caused by the drug. We measured kidney weight and renal water, protein, deoxyribonucleic acid (DNA), and ribonucleic acid (RNA) content and the renal RNA/DNA ratio in 72 rats distributed into groups as follows: left nephrectomized/cyclophosphamide-treated rats; left nephrectomized/saline treated rats; left nephrectomized rats submitted to food restriction and treated with saline; and left sham-nephrectomized rats treated with saline. An additional group of 12 rats was studied to obtain the initial values of the parameters. The parameters were also measured 1, 2 and 3 weeks after left nephrectomy or sham-operation. Cyclophosphamide was given once a week intraperitoneally at the dosage of 60 mg/kg body weight in saline. Corresponding volumes of saline were given to control animals. At the end of the 1st week all nephrectomized groups of rats showed some degree of renal compensatory growth. However, no significant differences in kidney weight, protein or RNA content were detected between controls, cyclophosphamide-treated rats, and animals submitted to food restriction at the end of the 2nd and 3rd week. We conclude that cyclophosphamide inhibits but does not abolish compensatory renal hypertrophy after uninephrectomy in the young rat and this inhibition is mediated primarily through the reduced food intake caused by the drug.

Adaptation, Physiological↗
PubMed1981

Endoscopic surgery: a new teaching method.

A new method of teaching endoscopic surgery with a canine model is described. Its main advantage over the few existing methods is that it best reproduces the events of the human transurethral resection.

Animals↗
PubMed1971

[Trichobezoars].

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Adult↗