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R Delgado

Publications and source records attributed to R Delgado.

At least 145 records · Page 8Linked to original sources
PubMed1986

Urothelial dysplasia and carcinoma in situ of the bladder.

Urothelial cells were pepsin-extracted from paraffin-embedded specimens taken from human nontumorous bladder mucosa, dysplasia, and carcinoma in situ. After Feulgen staining for DNA, nuclei were measured with an integrating microdensitometer. The measurements show that normal urothelium consists mostly of diploid nuclei. Dysplasia means that there is a predominance of tetraploid DNA values, whereas carcinoma in situ is characterized by a high percentage of aneuploid cells. In both dysplasia and carcinoma in situ there is a considerable percentage of diploid nuclei. Thus, DNA cytophotometry can be used for standardization of preneoplastic and early stages of tumor development in bladder cancer.

Carcinoma in Situ↗
PubMed1986

Monocyte-macrophage participation in atherogenesis: inflammatory components of pathogenesis.

This article has addressed the roles of the monocyte-macrophage in atherogenesis and factors influencing monocyte recruitment to the intima. The diversity of the secretory products of the macrophage and their putative participatory roles in pathogenesis have been reviewed and discussed. Additionally, we have presented summary data on the monocyte chemoattractant peptide SMC-CF and on the differentiation of the monocyte-derived foam cell. Discussion has centered on the concept of atherosclerosis as an inflammatory process.

Animals↗
PubMed1985

Extraction of cells from paraffin-embedded tissue sections for single-cell DNA cytophotometry.

A simple technique is presented for the isolation of cells from paraffin-embedded tissues for Feulgen DNA cytophotometric investigations. Tissue fragments from paraffin blocks were deparaffinized in xylene, rehydrated and refixed in a formalin solution and incubated in a solution of 0.5 pepsin in 0.25% hydrochloric acid. After filtration through a 70 micron mesh and centrifugation, the cells were smeared upon a glass slide. Comparison between the results obtained with freshly prepared imprints and with pepsin-extracted cells of the same tumor showed that the extraction technique does not influence the Feulgen reaction or the DNA distribution pattern. Investigations carried out on bladder and embryonal carcinomas have demonstrated that the method permits an analysis of histologically or histochemically identified tumor cells within individual tissue areas.

Cell Separation↗
PubMed1984

DNA-Feulgen-cytophotometric analysis of single cells isolated from paraffin embedded tissue.

This study describes a method for the isolation of cells from paraffin embedded tissues for DNA-Feulgen-cytophotometric measurements. The relevance of the method used is demonstrated by the analysis of the DNA-distribution pattern of cells isolated from an alveolar sarcoma of the soft tissues of a 10-year old girl. The comparison between freshly prepared imprint preparations and specimens after pepsin--extraction clearly shows, that the preparation mode used did not influence the relative DNA-content. The mean values of DNA/nuclei did not show a decrease even after prolonged pepsin treatment (90 minutes). Therefore this method permits access to stored histopathological material for retrospective DNA-Feulgen-Cytophotometric investigations.

Child↗
PubMed1984

Biological behaviour and DNA cytophotometry of urothelial bladder carcinoma.

In this prospective study, primary urothelial bladder tumour specimens from 64 patients were investigated by means of DNA Feulgen cytophotometry. The patients were followed clinically for at least 7 years. The objective cytophotometric parameters correlated well with the histopathological grading and the cytochemical data were of considerable prognostic value. They were closely correlated with the stage of the tumour, 5- and 7-year survival rates and the probability of tumour recurrence. It is concluded that DNA cytophotometry can serve as a method for the standardisation of histological grading and can give more objective and more detailed prognostic information than conventional histopathology.

Adult↗
PubMed1984

Infundibulopelvic stenosis in children.

Of 11,500 children who underwent excretory urography during a 17-year period, three were found to have the rare renal malformation infundibulopelvic stenosis, characterized by caliceal dilatation, infundibular stenosis, and hypoplasia or stenosis of the renal pelvis. The contralateral kidney was absent in two cases and normal in the other. Voiding cystourethrograms were normal in all three. Renal sonography showed a variable degree of caliceal dilatation without associated pelvic dilatation. The diagnosis was confirmed by retrograde ureteropyelography in one case. Two patients were followed for 12 and 18 months, respectively; both remained asymptomatic with normal renal function, and sequential sonographic examinations of their kidneys have shown no significant changes. The third patient died of an unrelated condition. Infundibulopelvic stenosis has highly characteristic radiographic features, and prognosis is good for most affected patients.

Child↗
PubMed1975

Renal blood flow distribution during steady-state exercise and exhaustion in conscious dogs.

To determine whether renal blood flow is reduced or redistributed during exercise, we measured total renal flow (TRF) and intrarenal flow distribution (IRFD) in nine dogs. They ran on a motor-driven treadmill at 3-8 mph at grades of 8-15% for an average of 35 min. We measured aortic pressure, heart rate, stroke volume, and cardiac output (CO) via chronically implanted catheters and an electromagnetic flow probe. We injected 15-mum radiolabeled microspheres (85Sr, 141Ce, and 51Cr) via a left atrial catheter during resting control, steady state (SS) and exhaustive (EE) exercise; measured their distribution by gamma spectrometry; and determined TRF as % CO and as ml/100 g per min. We determined IRFD for the outer and inner cortex and the outer medulla. TRF as %CO dropped (P less than 0.05) during both levels of exercise: from 10.2 +/- 0.7% to 3.9 +/- 0.4% (SS) and 3.4 +/- 0.6% (EE). TRF in ml/100 g per min did not change significantly from control (228 +/- 30 ml/100 g per min). IRFD was unchanged with exercise, remaining at about 80, 20, and 3% of TRF for the outer and inner cortex and outer medulla, respectively. We conclude that blood flow is not diverted from the kidneys during severe exercise in the dog.

Animals↗
PubMedDate not supplied

Osteosarcoma of the jaw.

BACKGROUND: Osteogenic sarcoma of the jaw has clinical and prognostic differences from that of long bones. METHODS: We reviewed 23 confirmed cases of osteosarcoma of the jaw seen at the Instituto Nacional de Cancerologia of Mexico between 1972 and 1990. RESULTS: Fifty-seven percent of the patients were women. Median age for all patients was 28 years. In 52% of cases, the neoplasm involved the maxilla. Tumor size ranged from 5 to 24 cm (median 10 x 7 cm) and 87% of the neoplasms were grade III or IV (Broder's). Twenty one (91%) patients were treated with surgery (s); radiotherapy (Rt) was administered to 14 (61%) and chemotherapy (Ct) to 11 (48%) patients. Clear (negative) surgical margins were obtained in 43% of surgically treated patients. Median follow-up for 20 patients eligible for evaluation was 16.5 months. Survival at 5 years was 10%. CONCLUSIONS: We found that tumor size and surgical margins were significant prognostic factors. Early diagnosis of these tumors is mandatory to improve survival; the role of Ct and Rt is still unknown.

Adolescent↗
PubMedDate not supplied

Activity against Mycobacterium tuberculosis with concomitant induction of cellular immune responses by a tetraaza-macrocycle with acetate pendant arms.

The novel tetraaza-macrocyclic compound 3,7,11-tris(carboxymethyl)-3,7,11,17-tetraaza-bicyclo[11.3.1]heptadeca-1(17),13,15-triene, abbreviated as ac3py14, was investigated for its activity against Mycobacterium tuberculosis and for induction of protective cellular immune responses. Perspective results show that ac3py14 and its Fe3+ 1:1 complex, [Fe(ac3py14)], inhibited radiometric growth of several strains of M. tuberculosis. Inhibition with 25 microg/mL varied from 99% for H37Rv to 80% and above for multiple drug-resistant clinical isolates. The capacity of ac3py14 to elicit a beneficial immune response without cellular apoptosis was assessed and compared to the effects of virulent M. tuberculosis. The present study produces evidence that after stimulation with ac3py14 there was significant production of interferon gamma (IFN-gamma), whereas the production of interleukin-5 (IL-5) remained low, and there was development of a memory population (CD45RO). The level of binding of Annexin V, a marker of apoptosis, was not sufficient to result in toxic effects toward alphabeta and gammadelta T cells and CD14+ macrophages. This preliminary study is the first report of a compound that simultaneously exerts an inhibitory effect against M. tuberculosis and induces factors associated with protective immune responses.

Adult↗
PubMedDate not supplied

Neurohormonal changes after implantation of a left ventricular assist system.

In patients with left ventricular dysfunction, neurohormonal levels are valuable indicators of the severity of heart disease and prognosis. For patients with severe left ventricular dysfunction, left ventricular assist systems (LVAS) are effective as short-term bridges to heart transplantation and are currently being investigated for long-term use. Unknown, however, are the effects of mechanical unloading of the left ventricle on neurohormone levels during the initial weeks after LVAS implantation, and whether these changes are similar to the neurohormonal level decreases observed after cardiac transplantation. This study was undertaken to determine the effect of LVAS support on plasma norepinephrine (PNE) levels during the initial weeks after device implantation. The PNE levels in five consecutive patients with left ventricular dysfunction were measured within 1 week after LVAS implantation and every week thereafter for 5 weeks. Significant decreases in PNE levels were observed after 3 weeks of LVAS support. After 5 weeks of LVAS support, PNE levels had decreased to near normal. For patients with severe left ventricular dysfunction, the improved prognosis after LVAS support may be due in part to the normalization of neurohormonal levels. The findings indicate that PNE levels may be of value in determining whether a patient can be weaned from LVAS support.

Aged↗