PubMed Health⌕ Search

Biomedical subjects

G Mendez

Publications and source records attributed to G Mendez.

At least 37 records · Page 2Linked to original sources

Significance of intrapancreatic gas demonstrated by CT: a review of nine cases.

Nine patients with intrapancreatic air were encountered among 450 patients evaluated for pancreatic pathology. Eight of these patients had surgically proven pancreatic abscesses. The ninth had spontaneous perforation of a pancreatic pseudocyst into the gastrointestinal tract as an explanation of the intrapancreatic air. Computer tomography has been found to be very helpful, not only in the initial diagnosis of pancreatic abscessses, but also in the evaluation of distant spread of the infection. The presence of intrapancreatic air in our experience is the most reliable sign of a pancreatic abscess.

Abscess↗

Malignant external otitis: a radiographic-clinical correlation.

Malignant external otitis is an infectious process of the ear which may cause marked destruction of the surrounding bony structures. After evaluation of the plain skull films, mastoid series, temporal bone tomography, arteriography, and venography in nine cases of malignant external otitis, we divided the disorder into an early stage and late stage. The early stage is manifested by a soft tissue mass within the external canal or clouding of the mastoid air cells with no bone destruction. In the late stage, bone destruction may extend to the middle ear cavity, temporomandibular joint, and/or base of the skull. A correlation can be made between the clinical findings and these radiographic stages. Complex motion tomography is essential to appreciate the bone destruction in patients with late stage disease.

Aged↗

Fatty tumors of the thorax demonstrated by CT.

The radiographic signs previously described for fatty tumors of the thorax although helpful are nonspecific. In the past, the diagnosis of benign fatty tumors of the chest in asymptomatic patients required surgical intervention. This report illustrates the gamut of fat-containing tumors of the thorax encountered over a recent 1 year period. CT proved to be helpful in the diagnosis and management on these cases. When the CT numbers of the fatty lesion was around -55 EMI units, intervention was felt to be unnecessary. However, when the CT number of the mass ranged from --10 to--20 EMI units, intervention was felt to be necessary since a malignancy could not be excluded on the basis of the CT findings alone.

Adult↗

Pretransplant monitoring of donor-recipient compatibility.

In these studies, pretransplant testing of donor-recipient compatibility was performed in 10 related donor and 26 cadaveric renal transplants using a variety of cell-mediated immunity tests. Mixed lymphocyte culture results did not correlate with acute rejection (AR), acute irreversible rejection, or chronic rejection (CR). Lymphocyte-mediated cytolysis also did not correlate with AR, acute irreversible rejection, or CR. Cell-mediated lympholysis correlated with AR but not with acute irreversible rejection or CR. Antibody-dependent cell-mediated cytolysis (ADCMC) was positive pretransplant in 13 (36%) of the recipients. Of the positive patients, 4 had early severe AR and 9 developed typical CR. Of these 13 patients, 9 or 69% lost graft function to rejection whereas only 3 of 20 (15%) of ADCMC-negative patients lost graft function because of rejection (P less than 0.05). In summary, cell-mediated lympholysis testing demonstrated a capability to predict AR episodes. The most useful pretransplant monitoring assay in this patient series was the ADCMC assay. A positive ADCMC against donor cells pretransplant indicates a relatively poor prognosis for long-term graft survival.

Antibody-Dependent Cell Cytotoxicity↗

Studies of thymus-derived and bone marrow-derived lymphocytes in renal transplant patients.

Serial studies of levels and responsiveness of T and B lymphocytes were performed in human renal allograft recipients. Patients given prednisolone-azathioprine immunosuppression had only mild falls in levels and responsiveness of T cells. Patients given a quality controlled ATG preparation had marked and relatively selective falls in levels of T cells associated with a marked fall in T cell responsiveness as measured by PHA and Con-A responsiveness. In vivo correlates of this severe T cell deficiency suggest that T lymphocytes are central to acute allograft rejection and that acute severe T cell deficiency is not associated with risk of infectious complications above and beyond those seen in patients suppressed with prednisone-azathioprine alone. These studies suggest that ATG, produced under quality control conditions and having rather selective anti-T cell activity, is a useful adjunctive immunosuppressive agent for human renal transplantation.

Antilymphocyte Serum↗

Direct-injection NMR (DI-NMR): a flow NMR technique for the analysis of combinatorial chemistry libraries.

A new tool for analyzing compound libraries by NMR has been developed. Aliquots of solution-state samples (between 120 and 350 microL) are directly injected, using a standard liquids handler, into an NMR (LC-NMR) flow probe. Automated NMR software tracks--and suppresses--intense signals arising from the nondeuterated solvents used (if any) and acquires high-sensitivity one-dimensional 1H NMR spectra. An 88-member combinatorial library, dissolved in DMSO and stored in a 96-well microtiter plate, has been analyzed a number of ways using this technique. This nondestructive technique, which we call direct-injection NMR (DI-NMR) and which is embodied in our versatile automated sample changer (VAST) hardware, has proven to be both routine and robust. Our success in automatically acquiring the NMR data for entire plates of library compounds (within 4-8 h) has caused us to develop new ways to display and analyze the resulting NMR data, as will be shown here.

Chemistry, Organic↗