PubMed Health⌕ Search

Biomedical subjects

J Baxter

Publications and source records attributed to J Baxter.

At least 91 records · Page 5Linked to original sources
PubMed1989

OKT3 prophylaxis versus conventional drug therapy: single-center perspective, part of a multicenter trial.

As part of a collaborative study, Orthoclone OKT3 (Ortho Pharmaceutical Corporation, Raritan, NJ) monoclonal anti-T-cell antibody was used prophylactically for 14 days following cadaveric renal transplantation. Patients were randomized before treatment and compared with a control group treated with triple-drug immunosuppressant therapy consisting of cyclosporine, azathioprine, and prednisone. The OKT3 group (also treated with prednisone and azathioprine) had significantly fewer patients with acute rejection during the first year (27% v 60%), significantly delayed onset of acute rejection (median number of days to rejection, 56 v 10), and shortened duration of delayed initial graft function (median number of days on nonfunction, 5.5 v 9.0). OKT3 was safely administered intraoperatively. The study group included diabetics and patients over the age of 50 years. There was an increased incidence of benign fungal infection in patients treated with OKT3. The outcome data of both the prophylactic and control groups in this single-center trial was different from the multicenter experience in that patient and graft survival was 100% in both groups. The only difference in the immunosuppressive protocol was the use of 2 g intravenous methylprednisolone intraoperatively. The combination of intraoperative OKT3 with 2 g methylprednisolone may merit further study. It was concluded that OKT3 prophylaxis reduces the incidence of rejection episodes, delays the occurrence of rejection, and may reduce the duration of delayed initial graft function. It is not associated with an increase in serious infection and can be administered safely to a variety of cadaver transplant recipients.

Antibodies, Monoclonal↗
PubMed1988

Comparability of mortality follow-up before and after the National Death Index.

Prior to 1979, epidemiologic studies which included mortality follow-up on large cohorts relied on death certificates from last state of residence and expensive follow-up techniques to determine survival. Beginning with 1979, the National Death Index can be used to search death certificate files from all 50 states, the Virgin Islands, and Puerto Rico. This paper addresses the issue of whether mortality follow-up in epidemiologic studies based on a single state death certificate search using only data available in 1970-1975 can be compared with post-1979 mortality follow-up using the National Death Index. This question was addressed by following a cohort of 2,925 coronary heart disease and cerebrovascular disease 1980 hospital discharges from 1980 through 1983 with the use of both the National Death Index and the Minnesota Death Index (MINNDEX). Algorithms for evaluating potential death certificate matches were developed independently for both systems. The systems agreed on the survival status of 98% of the cohort, and both identified 31% as dead. This study supports the comparison of results of National Death Index follow-up to pre-National Death Index studies using algorithms such as the MINNDEX, and provides evidence that trend analyses relying on single state death searches pre-1979 and on the National Death Index from 1979 are valid, particularly in chronically ill persons.

Adult↗
PubMed1988

Four-year experience with exclusive use of cytomegalovirus antibody (CMV-Ab)-negative donors for CMV-Ab-negative kidney recipients.

Because of unacceptable CMV related morbidity, mortality, and graft loss, we adopted a policy that (-) patients would receive renal allografts only from (-) donors. This policy has resulted in a significant decrease in (1) morbidity (10.6% v 1.7%, P less than .0001), (2) mortality (3.7%) v 0%, P = .002), and (3) graft loss (2.5% v 0%, P = .016). CMV-Ab-negative patients (1) constitute 26% of all patients tested (compared with 36% of all donors tested), (2) receive transplants at the same rate as (+) patients, (3) do not have a prolonged waiting time, and (4) received greater HLA-A, B, -DR mismatched kidneys (3.6 v 3.1, P less than .01).

Antibodies, Viral↗
PubMed1987

Infection-resistant continuous peritoneal dialysis catheters.

The techniques of bonding of anionic antibiotics by treatment with cationic surfactants were applied to continuous ambulatory peritoneal dialysis (CAPD) catheters. The elution of 14C-penicillin from tridodecylmethylammonium chloride (TDMAC) treated silicone elastomer catheters in dialysis solution was biphasic, with 95% dissociated from the catheter by 48 h. Forty percent of the TDMAC left the catheter surface during the initial 2 days. The ability of the surfactant TDMAC to bind antibiotics after incubation in dialysis solution correlated directly with the amount of surfactant remaining. Rats with intraperitoneal dialysis catheters were inoculated with exit site and intraluminal bacterial challenges. Intraperitoneal catheter tips treated with TDMAC-penicillin were rendered more resistant to colonization after exit site and intraluminal bacterial challenges.

Animals↗
PubMed1987

OKT3 rescue in refractory renal rejection.

A community hospital-based transplant program participated in the study of Orthoclone OKT3 as a treatment for refractory renal rejection. A total of 16 patients receiving varied oral immunosuppressive regimens, and developing steroid-resistant acute rejection, were treated with OKT3. Thirteen of the 16 patients completed a 10-day course of therapy with reversal of rejection in all 13. Rerejection occurred in 1 of the 13 patients; the remaining 12 have normal renal function. Fever, chills, and diarrhea were the most common side effects, lasting an average of 72 h. Based on this experience, OKT3 was found to be an effective drug in refractory rejection with minimal complications or risks of administration.

Adult↗
PubMed1986

Cloning, sequence analysis, and processing of the rat and human atrial natriuretic peptide precursors.

Complementary DNA sequences and structural genes encoding the atrial natriuretic peptide precursor (prepro-ANP) have been cloned. Analysis of DNA sequences, complementary to rat atrial prepro-ANP mRNA, has revealed that the various natriuretic peptides isolated from rat atrium reside at the carboxy terminus of a 152-amino-acid precursor protein. The human gene, comprised of three exons and two intervening sequences, encodes a protein of 151 amino acids highly homologous to the rat precursor. Although putative proteolytic processing sites can be identified throughout the prepro-ANP amino acid sequence, the natural form of the mature ANP has not been identified. Therefore, the sites and mechanisms of prepro-ANP processing to mature peptides forms are unknown. However, the successful cloning of the prepro-ANP gene and corresponding cDNAs provide the necessary molecular tools to address these fundamental questions relating to the regulation of ANP synthesis and processing in atrial and extraatrial tissues.

Amino Acid Sequence↗
PubMed1985

Cellular sensitivity to glucocorticoids in patients with POAG. Steroid receptors and responses in cultured skin fibroblasts.

The question of a generalized hypersensitivity to corticosteroids in primary open-angle glaucoma (POAG) was investigated using cultured skin fibroblasts from patients with POAG and age-matched controls. Nuclear binding of (3H)-dexamethasone was performed to evaluate possible changes in the glucocorticoid receptors. Cortisol effects on (3H)-thymidine uptake into the cells were investigated as a measure of the cellular sensitivity to corticosteroids. When POAG and control groups were compared, no significant differences (P less than 0.05) were found for either the number or affinity of glucocorticoid receptors (POAG: Kd = 6.1 +/- 1.0 nM, Rt = 94 +/- 13 sites/cell X 10(3); control: Kd = 5.5 +/- 1.6 nM, Rt = 124 +/- 20 X 10(3) sites/cell) or for cortisol effects on thymidine uptake (POAG: C50 = 83 +/- 38 nM; control: C50 = 80 +/- 34 nM). Use of epidermal growth factor (EGF) resulted in an increased steroid sensitivity in some cell lines, but again no differences between POAG and control groups were detected. These results suggest that a generalized cellular hypersensitivity to glucocorticoids is not intrinsic to POAG. It is possible that environmental alterations and/or endogenous factors may influence the steroid responses observed in these patients.

Adult↗
PubMed1984

Cardiovascular mortality trends in Minnesota, 1960-1978. The Minnesota Heart Survey.

Age-adjusted mortality rates from coronary heart disease (CHD) and other causes were examined in Minnesota for the years 1960-1978. Regions differed in CHD mortality levels and time trends. The greatest decline in CHD mortality occurred in the Twin Cities. The Northeast region had the highest CHD mortality. Influenza and pneumonia death rates were unrelated to CHD trends. Stroke mortality, which also declined sharply, showed no regional differences. Cancer mortality was highest in the Twin Cities and Northeast regions and increased significantly over the period; most of this increase was due to a striking increase in lung cancer mortality. The authors conclude that: (1) the CHD mortality decline in Minnesota was similar to that in the United States; (2) regional differences within the state in CHD mortality levels and trends were statistically significant; (3) CHD trends were not explained by influenza epidemics; (4) regions differed in mortality rates for hypertension in the same way as they did in CHD mortality, but differed little in stroke mortality. This leaves unclear the role of hypertension in regional CHD differences. (5) Trends in cancer mortality indicate that a general decline in mortality, due to factors affecting a wide variety of diseases does not explain the downward trends in CHD mortality.

Adult↗
PubMed1984

[Initial division of Isospora sporozoites from a sparrow in cell culture].

The study of the sparrow Isospora in cell culture has demonstrated that during the extra-intestine life cycle, sporozoites undergo a primary division, resulting into two similar elements, whereas, in plain intra-intestinal cycle, the sporozoite is straightforwardly transformed into the first generation schizont.

Animals↗
PubMed1984

Inhibition of Leishmania amastigote growth by antipain and leupeptin.

Antipain and leupeptin were found to be potent inhibitors of the growth of Leishmania mexicana mexicana amastigotes in explanted mouse unstimulated peritoneal macrophages. Antipain at 100 mg l-1 reduced eight-fold the percentage of macrophages infected and to 5% of the control the number of amastigotes present after seven days incubation. At 1 mg l-1, antipain and leupeptin were as effective antileishmanial agents as pentamidine isethionate, all three stopping parasite multiplication over the seven-day incubation.

Animals↗
PubMed1984

Coronary heart disease mortality trends in Minnesota, 1960-80: the Minnesota Heart Survey.

Age-adjusted mortality rates and trends from coronary heart disease (CHD) in Minnesota for the years 1960 to 1980 differed among eight health service areas. Regression of ten socioeconomic and demographic factors and intensive care and coronary care unit beds on area CHD mortality levels and slopes revealed a significant positive association only for levels of welfare income-maintenance assistance with CHD mortality levels; there were no associations with trends. Further studies are needed to explain variation within states of CHD mortality rate levels and trends.

Adult↗
PubMed1984

Diagnosis of brain death in children by radionuclide cerebral imaging.

Nine children with clinically suspected brain death were evaluated by radionuclide cerebral imaging and four-vessel dye contrast cerebral arteriography. The scans showing absence of cerebral blood flow were verified by arteriography in all children. There was complete agreement in all cases. It was concluded that failure to detect cerebral blood flow by radionuclide cerebral imaging in children is a valid demonstration of absence of cerebral circulation for purposes of determining brain death. The scan is significantly less expensive than dye-contrast arteriograms. The test is portable, and thus it eliminates the need for transportation of extraordinarily ill patients. The scanning technique is noninvasive and may be particularly helpful in the diagnosis of brain death in patients in whom intravenous infusions of barbiturate might otherwise obscure the clinical and EEG examination.

Adolescent↗
PubMed1983

Radionuclide cerebral imaging confirming brain death.

Cerebral blood flow (CBF) was measured by portable radionuclide cerebral imaging (RCI) and by four-vessel cerebral contrast arteriography in 15 clinically brain-dead patients, including six children. Neither technique showed evidence of CBF, although four RCI scans showed sagittal sinus activity. Portable scanning techniques are therefore considered valid determinants of brain death and may be useful in lieu of contrast cerebral arteriography.

Adolescent↗