Search PubMed⌕ Search

Biomedical subjects

J A Roth

Publications and source records attributed to J A Roth.

At least 361 records · Page 20Linked to original sources
PubMed1990

Multidisciplinary therapy for esophageal cancer.

The use of combined-modality therapy programs, including systemic chemotherapy plus radiotherapy, are being studied intensively, since pilot trials have consistently shown improvement in 1- or 2-year survival statistics compared with historic controls. The mechanisms of interaction of the most popular chemotherapeutic drugs (5-FU, mitomycin C, and cisplatin) when used with irradiation are not fully understood. Further clinical work will be necessary to optimize the best combination of agents, their dose levels, and method and schedules of administration. Pathologic complete responses ranging from 37 to 45% have been reported in some series using preoperative chemoradiation and may translate into better survival rates for some patient subgroups. Several randomized multiinstitutional trials are underway to assess the utility of chemoradiation in comparison to radiotherapy alone in order to confirm these initial encouraging results. From these data, it would be prudent to consider the use of 5-FU continuous infusion treatment with or without other chemotherapeutic agents in conjunction with conventionally fractionated irradiation. Radiotherapy should be given in a continuous fractionated course rather than given as a split course. With these guidelines, the acute complications and late complications seem to be acceptable and not increased over those expected with radiotherapy alone.

Combined Modality Therapy↗
PubMed1989

Analysis of gp74 expression by transformed rat fibroblasts from experimental pulmonary metastases following specific ricin A-chain immunotoxin therapy.

Ricin A chain immunotoxin (IT) 45-2D9-RTA mediates regression of spontaneous pulmonary metastases and lung colonies from K-ras transformed rat fibroblasts (TRF cells). However, residual metastases are frequently noted after IT therapy, and therefore, possible mechanisms mediating tumor cell escape were investigated. Individual lung colonies were dissected from lungs of BALB/c mice, and single-cell suspensions of fresh cells from short-term cultures (eight passages) were tested. Immunoperoxidase staining with 45-2D9 monoclonal antibody showed that stable loss of surface antigen by cells cultured from IT-treated mice did not occur after four injections of specific IT. Sensitivity to specific IT in vitro was equal for metastatic tumor cells from mice treated with either two or four doses of specific IT compared to cells from nonspecific IT-treated mice and to parental cells. Clones derived from metastases of IT-treated mice were not resistant to IT. Clones derived from metastases of specific IT-treated mice internalized bound antibody or IT at the same rate as untreated cells. Freshly disaggregated cells from specific IT-treated mice were as sensitive to specific IT as were cells from nonspecific IT-treated or untreated mice. Specific IT successfully mediated reduction of lung colonies derived from fresh suspensions of lung colony TRF cells from IT-treated mice. This reduction was equivalent to that seen for cells not previously exposed to specific IT. Immunoperoxidase stains of lung sections with 45-2D9 showed that colonies consisting entirely of unstained TRF cells were present in both specific IT and phosphate buffered saline-treated mice. There was a trend toward a higher percentage of antigen-negative colonies in mice treated with IT, although 9 days following specific IT therapy, greater than 80% of lung colonies expressed gp74 antigen. When TRF cells were grown on agar plugs, which promoted three-dimensional growth, groups of cells showing absence of immunoperoxidase staining with antibody to gp74 were identified during 2 weeks of growth. Thus, stability of antigen-negative variants is favored by three-dimensional growth conditions and the selective pressure of IT administration. Our results also suggest that impaired trafficking of IT to antigen-positive cells may also contribute to escape from IT therapy.

Animals↗
PubMed1989

Differential expression of the c-erbB-2 gene in human small cell and non-small cell lung cancer.

We studied non-small cell lung cancers (NSCLC) from 60 patients for abnormalities in the c-erbB-2 gene. Eleven human lung cancer cell lines, including four derived from small cell lung cancer (SCLC) and seven derived from NSCLC were also examined for altered c-erbB-2 gene expression. Southern blot analysis of paired tumor and normal lung samples demonstrated that amplification of the c-erbB-2 gene is rare in NSCLC (2/60) and not restricted to adenocarcinomas. One patient showed an EcoRI restriction fragment length polymorphism for the c-erbB-2 locus. Four of four SCLC cell lines demonstrated minimal or nondetectable expression of c-erbB-2 mRNA compared to high levels of expression by seven of seven NSCLC lines. The highest expression levels were seen in four of four adenocarcinomas. We conclude that c-erbB-2 expression is different in SCLC compared to NSCLC and high expression of c-erbB-2 is consistently present in lung adenocarcinomas.

Blotting, Northern↗
PubMed1989

Pathologic analysis of advanced adult soft tissue sarcomas, bone sarcomas, and mesotheliomas. The Eastern Cooperative Oncology Group (ECOG) experience.

A total of 488 tumors entered in the Eastern Cooperative Oncology Group (ECOG) Study EST 3377 were evaluated histologically by a panel of pathologists from member institutions for quality control purposes. The overall agreement rate between the eligible submitting diagnosis and the pathology review panel's diagnosis was 74% (312/424). In 10% (44/424), the case was excluded because it was deemed to be nonsarcoma. In the other 16%, the disagreement concerned the type of sarcoma. The histologic type with the lowest agreement rate was rhabdomyosarcoma (17%), followed by sarcoma not otherwise specified (NOS) (27%), angiosarcoma (33%), and fibrosarcoma (48%). These figures reflect the significant degree of difficulty in the diagnosis of these tumor types. The treatment response rate of soft tissue sarcomas in the randomized study of Adriamycin (Adria Laboratories, Columbus, OH) regimens was slightly higher for those with lower grade sarcomas, i.e., 25% (four of 16) response rate for Grade 1 lesions; 22% (17/77) for Grade 2, and 21% (35/170) for Grade 3. When adjusted for type of sarcoma, there was no noticeable difference between Grade 1-2 versus 3 in response rate. A statistically significant difference in the percentage of complete responders was noted between Group A tumors (synovial sarcoma, hemangiopericytoma, sarcoma NOS, and Ewing's; 12.2%) versus Group B tumors (all other types--mostly spindle cell sarcomas; 3.5%) (P = 0.02).

Adolescent↗
PubMed1989

Analysis of expression of cell surface antigen Mr 74,000 phosphoglycoprotein in normal, oncogene-transformed, and neoplastic rat cell lines.

A Mr 74,000 phosphoglycoprotein (gp74) present on the surface of oncogene-transformed murine cells but not untransformed NIH 3T3 cells was previously identified with mouse monoclonal antibody 45-2D9. The original cell population used as the immunogen was found to consist of two cell populations. The purpose of this study was to characterize these cell populations; determine the distribution of gp74 on normal, transformed, and neoplastic cells; and to characterize the gp74 molecule. Southern hybridization studies of cloned cell populations demonstrated that the immunizing cell population consisted of c-Ha-ras-transfected NIH 3T3 cells and Kirsten sarcoma virus-transformed rat cells (TRF cells). TRF cells showed a high level of gp74 expression. We observed that the expression of gp74 was increased on chemically and spontaneously transformed rat cells compared to untransformed rat cells. No binding of monoclonal antibody 45-2D9 was detected to rat adult and fetal tissue. Immunoperoxidase staining, immunofluorescence flow cytometry, and immunoprecipitation analysis of dimethylbenz[a]anthracene-induced metastatic 13762NF rat mammary adenocarcinoma clonal sublines demonstrated an inverse relationship between gp74 expression and metastatic phenotype. gp74 was immunoprecipitated from two low and medium metastatic clonal sublines (MTC and MTF7), but not from highly metastatic clone MTLn3 cells. Biosynthetic labeling and immunoprecipitation studies demonstrated that gp74 was phosphorylated on serine residues and was not secreted from transformed cells. No detectable protein kinase activity in an immune complex assay was associated with this molecule. We conclude that increased gp74 expression by rat cells is associated with transformed and neoplastic cells.

Animals↗
PubMed1989

Characterization of tyrosylprotein sulfotransferase from rat liver and other tissues.

The sulfoconjugation of tyrosyl residues is a widespread post-translational modification of biologically active peptides and proteins. In this paper we describe the characterization of a rat liver tyrosylprotein sulfotransferase that is capable of catalyzing the transfer of a sulfate moiety from 3'-phosphoadenosine 5'-phosphosulfate (PAPS) to the synthetic polymer, poly-(Glu6,Ala3,Tyr1) (EAY; Mr 47,000) using a simple filter paper assay. Following sucrose density gradient centrifugation and comparison with known subcellular marker enzyme activities, rat liver tyrosylprotein sulfotransferase activity was shown to have a distribution similar to the Golgi enzyme, galactosyltransferase. Using the enriched Golgi preparation, rat liver tyrosylprotein sulfotransferase displayed a pH optimum of 6.7 and required the presence of 20 mM Mn2+ for maximal activity. Co2+ (20 mM) was able to produce 26% of the maximal stimulation observed with Mn2+, whereas other metal ions, such as Mg2+, Ca2+, and Co2+, were not effective in stimulating tyrosylprotein sulfotransferase activity. Whereas tyrosylprotein sulfotransferase activity was observed in the native membrane-bound state, EAY sulfation was maximally enhanced 3-fold when assayed in the presence of Lubrol Px. Under the optimal conditions for assaying the sulfation of EAY by a rat liver enriched Golgi fraction, significant degradation of the sulfate donor, PAPS, was observed. The addition of both NaF and 5'-AMP to the incubation mixture was found to effectively prevent PAPS degradation and increase the amount of product formed in the assay by 10-fold. Using the optimized conditions for the sulfation of EAY by rat liver tyrosylprotein sulfotransferase, membrane-bound sulfotransferase activity was also observed in the crude microsomal pellets of a variety of rat tissues, including lung, pituitary, and cerebellum, as well as in livers from different species.

Animals↗
PubMed1989

Role for arachidonic acid metabolism and protein synthesis in recombinant bovine interferon-gamma-induced activation of bovine neutrophils.

Bovine neutrophils were preincubated with recombinant bovine interferon-gamma (rboIFN-gamma), and the molecular events leading to enhanced antibody-dependent (ADCC) and antibody-independent (AINC) neutrophil-mediated cytotoxicity and reduced random migration under agarose were investigated. Addition of alpha-amanitin, puromycin, or cycloheximide (RNA and protein synthesis inhibitors) during preincubation and assaying prevented the rboIFN-gamma-induced AINC enhancement and migration inhibition, but did not influence the enhancement of ADCC. Treatment of neutrophils with rboIFN-gamma consistently increased the synthesis of a 60 and a 94-95 kilodalton protein and of leukotriene B4 and 5-HETE. Neutrophils isolated from dexamethasone-treated cattle showed similar protein synthetic activity after rboIFN-gamma treatment, but these cells failed to show enhanced AINC. Neutrophils from dexamethasone-treated cattle have been shown to have depressed arachidonic acid metabolism. Addition of lipoxygenase inhibitors (NDGA and BW755c) to neutrophils from nondexamethasone-treated cattle following preincubation with rboIFN-gamma (i.e., after protein synthesis had occurred) eliminated the enhancement of AINC. Thus it was concluded that the metabolic events required for neutrophil activation by rboIFN-gamma are different for the three functions measured. The enhanced AINC response required both arachidonic acid metabolism and protein synthesis, inhibition of random migration required only protein synthesis, and enhancement of ADCC required neither.

Animals↗
PubMed1989

Cancer-induced immunosuppression: implications for therapy?

Cancer-induced immunosuppression can be caused by a variety of effects. These include factors produced by the host in response to the presence of tumor or factors elaborated by the tumor itself. Disseminated tumor can lead to host debility with associated anergy. Some immunosuppressive effects are due to the manner in which the host processes (or fails to process) the tumor as an antigenic stimulus. Lastly, antitumor treatments can have a detrimental impact on host antitumor immunity. Recent research findings from our laboratories implicate surgical stress effects and tumor-mediated production of growth factors such as transforming growth factor beta (TGF-beta) as being important causes of host immune impairment. An accurate understanding of the mechanisms underlying host antitumor immune impairment will be critical in the successful development of immunotherapy strategies for use in the surgical oncology patient.

Animals↗
PubMed1989

Induction of lymphokine-activated killer cytotoxicity with interleukin-2 and tumor necrosis factor-alpha against primary lung cancer targets.

Human peripheral blood mononuclear cells (PBM) activated with recombinant interleukin-2 (IL-2) generate potent lytic activity (LAK) against a variety of malignant cells. IL-2 alone is sufficient for LAK generation, but high concentrations are needed to generate optimal cytotoxicity. Our recent studies based on combinations of biological agents indicated that alternative activation pathways may exist. Synergy for LAK induction was investigated using IL-2 and tumor necrosis factor-alpha (TNF). Single-cell suspensions of primary human lung carcinomas were prepared from seven established cell lines and 32 fresh tumor specimens. Not only were all cell lines sensitive to allogeneic LAK, but also all fresh tumors were sensitive to some degree to both autologous and allogeneic LAK lysis measured by a 4-h 51Cr-release assay. LAK-mediated cytotoxicity, induced with a combination of human recombinant IL-2 (Cetus, 100 U/ml) and TNF (Genentech, 500 U/ml), showed a mean fourfold increase (range 0.7-16.3) over IL-2 alone. No lytic activity was generated from PBM incubated with media or TNF alone. The sequence dependence of adding IL-2 and TNF in enhancing cytolytic activity was also studied. In vitro kinetics data revealed that the addition of TNF 2-6 h before the addition of IL-2 greatly increased LAK activity over that obtained from the simultaneous addition of the two cytokines. These results demonstrated (a) the synergy of IL-2 and TNF for generating LAK; (b) the lysis of fresh primary lung cancer cells by LAK; and (c) the sequence dependence of IL-2 and TNF for the induction of optimal LAK activity.

Carcinoma, Non-Small-Cell Lung↗
PubMed1989

Determinants of perioperative morbidity and mortality after pneumonectomy.

A total of 197 consecutive patients undergoing pneumonectomy at the M.D. Anderson Cancer Center from 1982 to 1987 were reviewed. Sixty-five variables were analyzed for the predictive value for perioperative risk. The operative mortality rate was 7% (14/197). Patients having a right pneumonectomy (n = 95) had a higher operative mortality rate (12%) than patients having a left pneumonectomy (1%, p less than 0.05). The extent of resection correlated with the operative mortality rate (chest wall resection or extrapleural pneumonectomy, n = 39, 15%; versus simple or intrapericardial pneumonectomy, n = 158, 5%; p less than 0.05). Patients whose predicted postoperative pulmonary function, by spirometry and xenon 133 regional pulmonary function studies, was a forced expiratory volume in 1 second greater than 1.65 L, forced expiratory volume in 1 second greater than 58% of the preoperative value, forced vital capacity greater than 2.5 L, or forced vital capacity greater than 60% of the preoperative value had a lower operative mortality rate (p less than 0.05). Atrial arrhythmia was the most common postoperative complication (23%). Xenon 133 regional pulmonary function studies are useful in predicting the risks of pneumonectomy.

Aged↗
PubMed1989

Effects of in vitro and in vivo administration of recombinant bovine interferon-gamma on bovine neutrophil responses to Brucella abortus.

The effects of in vitro and in vivo treatment of bovine polymorphonuclear leukocytes with recombinant bovine interferon-gamma on in vitro bovine polymorphonuclear leukocyte functions and the survival of Brucella abortus were determined. Activation of neutrophils in vitro with interferon-gamma resulted in enhanced production of O2- and myelopeoroxidase-H2O2-halide activity by neutrophils in the presence of B. abortus. The improved iodination responses were correlated with an enhanced ability to perform iodination in the presence of 5'-guanosine monophosphate and adenine which have previously been shown to contribute to inhibition of neutrophil myeloperoxidase-H2O2-halide activity by B. abortus. The ability of opsonized B. abortus to survive in the presence of neutrophils activated in vitro or in vivo was partially decreased by approximately 10% of control when compared to survival rates within control phagocytes. These results suggest that activation of neutrophils with recombinant interferon-gamma partially enhances their oxidative metabolic responses, resulting in a slightly enhanced ability to kill virulent B. abortus.

Animals↗
PubMed1989

In vivo effects of a thymosin alpha 1-containing colostral whey product on neutrophils and lymphocytes from lactating cows without and with experimentally induced Staphylococcus aureus mastitis.

Two separate experiments evaluated ID-1 (a commercial bovine whey product containing 5200 pg of thymosin alpha 1/ml) as an immunotherapeutic agent in lactating cows. In the first experiment, cows without mastitis were evaluated for blood leukogram, milk production, total and differential milk cell counts, lymphocyte (Lc) blastogenesis, and neutrophil (PMN) functions (random and directed migration under agarose, chemiluminescence, ingestion of bacteria, iodination, cytochrome C reduction, antibody-independent neutrophil-mediated cytotoxicity, and antibody-dependent cell-mediated cytotoxicity) before and after ID-1 therapy. ID-1 treatment resulted in a significant treatment group by time period interaction for the relative proportion of mononuclear cells (MNC) in milk (P less than 0.009) and for PMN random migration (P less than 0.01). Based on these interactions, ID-1 treatment appeared to slightly increase the proportion of small MNC in milk and to increase random migration from pretreatment levels by 73% more than increases observed in controls. No significant effect of ID-1 treatment on milk production, total milk somatic cell counts, Lc blastogenesis, or other PMN functions was observed. In cows with experimental Staphylococcus aureus intramammary infections, ID-1 treatment resulted in a significant decline in blood leukocyte count (P less than 0.001) and blood PMN count (P less than 0.02), and maintained PMN random migration (P less than 0.01) while controls declined and abrogated a depression in the ability of Lc to respond to mitogens (P less than 0.05) that developed in controls as a result of S. aureus mastitis. Injection of ID-1 into cows had no adverse effect on their overall health or level of milk production, but did cause subtle and potentially favorable changes in several in vitro immune parameters. In spite of these subtle changes which might indicate increased resistance to mastitis, cows actually developed a more severe S. aureus intramammary infection based on a 9% increase in log 10 bacterial shedding in milk.

Animals↗
PubMed1989

Current management of chest-wall tumors.

Chest-wall resection can be performed with low morbidity and mortality rates and remains the primary treatment for most chest-wall tumors. However, some lesions are best treated with a multimodality approach including preoperative chemotherapy. Therefore, pretreatment tissue diagnosis is essential in planning. The biopsy should be done at the medical center where the definitive treatment will be undertaken, and frequently, a needle biopsy will be sufficient. Osteosarcoma, rhabdomyosarcoma, Ewing's sarcoma, and other small-cell sarcomas are sensitive to chemotherapy, which should be given preoperatively, continued postoperatively, and modified according to the tumor response. Chondrosarcomas and most adult soft-tissue sarcomas are well controlled by primary excision and selective use of adjuvant irradiation. Better systemic and local therapy is needed for the recurrent soft-tissue sarcomas and the aggressive unclassified sarcomas. Chest-wall resection continues to play a primary role in the management of locally and regionally recurrent breast cancer but is best combined with systemic chemotherapy. Chest-wall resection can provide a long disease-free survival in patients with isolated metastases from sarcomas or carcinomas. In addition, significant palliation can be afforded patients with symptomatic chest-wall metastases and a shortened life expectancy.

Antineoplastic Agents↗
PubMed1989

Recombinant bovine interferon-gamma as an immunomodulator in dexamethasone-treated and nontreated cattle.

Three dosages (0.1, 0.5, and 2.5 mg/animal, subcutaneously), of recombinant bovine interferon-gamma (rBoIFN-gamma) were evaluated for their in vivo influence on neutrophil function and lymphocyte blastogenesis in cattle. The optimal of the three dosages tested (0.5 mg/animal or 1.1 x 10(6) U/animal) was then evaluated for its influence on neutrophils and lymphocytes in both normal and dexamethasone-treated cattle. One animal, which received 2.5 mg of rBoIFN-gamma, died by 24 h after administration due to acute diffuse interstitial pneumonia with interlobular edema and emphysema. The two highest dosages used caused fever at 24 h and the highest dosage caused a decrease in lymphocyte blastogenesis at 24 h after administration. The influence of rBoIFN-gamma on neutrophil function was dose dependent and depended on the baseline values for neutrophil function. Random migration by neutrophils was consistently inhibited in animals that received 0.5 mg or more of rBoIFN-gamma. Staphylococcus aureus ingestion and antibody-dependent cell-mediated cytotoxicity by neutrophils was enhanced by rBoIFN-gamma treatment in both dexamethasone-treated cattle and in nondexamethasone-treated cattle, which had relatively low values for these parameters before treatment. Iodination by neutrophils was also enhanced by rBoIFN-gamma when either a suboptimal concentration of neutrophil stimulant was used or when the cattle were treated with dexamethasone. In summary, the rBoIFN-gamma had greater immunomodulator activity in immunosuppressed than in normal cattle. The in vivo influence of rBoIFN-gamma therefore depends on the physiologic status of the animal.

Adjuvants, Immunologic↗
PubMed1989

Alterations in bovine neutrophil function during the periparturient period.

Neutrophils from 8 Holstein heifers were evaluated for function during the periparturient period. Random migration, ingestion of bacteria, superoxide anion production, native (nonenhanced) chemiluminescence, iodination, and antibody-dependent, cell-mediated cytotoxicity by neutrophils were determined. Foremilk samples were evaluated for bacteria. Significant (P less than 0.05) increases in random migration of neutrophils, iodination, and chemiluminescence were evident 2 weeks before parturition and then decreased dramatically by the first week after parturition. These impairments of neutrophil function after parturition may be manifested as a severe cumulative deficit in the native defenses afforded by the neutrophil.

Animals↗
PubMed1989

Cell specific enzyme markers as indicators of neurotoxicity: effects of acute exposure to methylmercury.

In order to assess the sensitivity of several cell specific enzyme markers (tyrosine hydroxylase (TH), glutamic acid decarboxylase, choline acetyltransferase, glutamine synthetase (GS), neuron specific and non-neuronal enolase and 2',3'-cyclic nucleotide phosphohydrolase (CNP] as indices of neurotoxicity, changes in their activities were monitored after rats were treated with two doses of the neurotoxic agent, methylmercury chloride (MMC). Comparisons were also made of any histopathological changes occurring in the tissues examined. At the low dose rate (3.36 mg Hg/kg, po, for 14 days), the rats exhibited less body weight gain compared to untreated animals. No change in either the neuronal or noneuronal enzyme markers was observed in brain but a significant increase in the myelin marker, CNP, and total enolase activity was seen in the optic nerve. Morphological evaluation by light microscopy indicated no discernible neuronal lesions in MMC-exposed animals. At the higher MMC dose (7.05 mg Hg/kg, po, for 7 days), there was about a 20% loss in the body weight of treated animals and partial hind limb paralysis was observed. Of all the neuronal marker enzymes examined, only TH was found to be decreased in the striatum. The proliferating astroglial marker, GS, was elevated only in the cerebellum. CNP was found to be decreased in both the optic and sciatic nerve. As in the lower dose group no pathological changes were observed at the light microscopic level in the brain of MMC-treated rats. These data suggest that of the cell specific marker enzymes studied, GS in the cerebellum and TH in the striatum may be useful biochemical markers for the neurotoxic action of MMC.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMed1989

Effect of chronic exposure to hexachlorophene on rat brain cell specific marker enzymes.

The neurotoxicity associated with chronic exposure to hexachlorophene (HCP) was evaluated by measuring the activity of seven cell specific marker enzymes in brain and by comparing these measurements to morphological changes analyzed by light microscopy. Animals were divided into two groups, the experimental group received HCP at a daily dose of 20 mg/kg p.o. for 53 consecutive days whereas the control group received an equivalent amount of the vehicle only. HCP produced no change in the rate of gain in body weight nor did it produce a statistically significant change in brain weight. Furthermore, no overt abnormal neurological symptoms were observed at this level of exposure to HCP. The white matter throughout the brain was extensively vacuolated in the HCP-treated rats, imparting a spongiform structure which was absent in the white matter of the control animal brains. The data obtained reveal that chronic HCP treatment produce little change in any of the neuronal marker enzymes with the exception of a significant decrease in tyrosine hydroxylase activity in the striatum. Of the nonneuronal enzymes assayed, a significant increase in non-neuronal enolase, glutamine synthetase, and 2',3'-cyclic nucleotide phosphohydrolase was observed in the sciatic nerve, hippocampus and optic nerve, respectively.

Animals↗