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1.
Ann Surg Oncol ; 27(Suppl 3): 983, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32699930

ABSTRACT

C.R. Farley and M.C. Perez contributed equally to this publication and are co-first authors. J.S. Zager and M.C. Lowe contributed equally to this publication and are co-corresponding authors.

2.
Ann Surg Oncol ; 27(6): 1978-1985, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32103415

ABSTRACT

INTRODUCTION: The eighth edition of the American Joint Committee on Cancer (AJCC8) Staging Manual provides important information for staging and prognostication; however, survival estimates for patients with Stage I-III Merkel cell carcinoma (MCC), a rare disease, may be as practical using data from large-volume centers as that collated for the AJCC analysis. As such, we compared our institutional outcomes to AJCC8. METHODS: Patients who presented from 2005 to 2017 with MCC to two high-volume centers were included. Demographics, clinicopathologic characteristics, survival and recurrence data were compiled, and outcomes compared to AJCC8. RESULTS: A total of 409 patients were included. Median age was 75 (range 29-98) years, and 68% were male. Median follow-up was 16 months (0-157). Five-year overall survival (OS) was 70%; 5-year disease-specific survival (DSS) was 84%. When stratified by extent of disease, 5-year OS was higher for patients with local disease compared to those with nodal disease (72.6% vs 62.7%, p=0.005). Similarly, patients with local disease had higher 5-year DSS than those with nodal disease (90.1% vs 76.8%, p=0.002). Five-year recurrence-free survival was 59.2% for all patients, 65.0% for local disease and 48.3% for nodal disease (p=0.033). CONCLUSIONS: Here, MCC patients with local or nodal disease have substantially higher OS rates than predicted in AJCC8 (5-year: 72.6% vs 50.6%; 62.7% vs 35.4%, respectively). Importantly, 5-year DSS was significantly better than the OS rates reported presently and in AJCC8. As clinicians and patients rely on AJCC to accurately prognosticate and guide treatment decisions, these estimates should be reassessed and updated to more accurately predict survival outcomes.


Subject(s)
Carcinoma, Merkel Cell/mortality , Carcinoma, Merkel Cell/pathology , Neoplasm Staging , Skin Neoplasms/mortality , Skin Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Analysis , Time Factors , United States/epidemiology
3.
Am J Transplant ; 17(9): 2285-2299, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28502128

ABSTRACT

Recently, newer therapies have been designed to more specifically target rejection in an effort to improve efficacy and limit unwanted toxicity. Belatacept, a CD28-CD80/86 specific reagent, is associated with superior patient survival and graft function compared with traditional therapy, but its adoption as a mainstay immunosuppressive therapy has been tempered by increased rejection rates. It is essential that the underlying mechanisms associated with this rejection be elucidated before belatacept is more widely used. To that end, we designed a study in a nonhuman primate kidney transplant model where animals were treated with either a belatacept- or aĀ tacrolimus-based immunosuppressive regimen. Interestingly, we found that elevated pretransplant frequencies of CD28+ CD8+ TEMRA cells are associated with rejection on belatacept but not tacrolimus treatment. Further analysis showed that the CD28+ CD8+ TEMRA cells rapidly lose CD28 expression after transplant in those animals that go on to reject with the allograft infiltrate being predominantly CD28- . These data suggest that CD28+ memory T cells may be resistant to belatacept, capable of further differentiation including loss of CD28 expression while maintaining effector function. The unique signaling requirements of CD28+ memory T cells provide opportunities for the development of targeted therapies, which may synergize with belatacept to prevent costimulation-independent rejection.


Subject(s)
Abatacept/pharmacology , CD28 Antigens/immunology , CD8-Positive T-Lymphocytes/immunology , Drug Resistance/immunology , Graft Rejection/immunology , Immunologic Memory/immunology , Kidney Transplantation/adverse effects , Animals , CD28 Antigens/metabolism , CD8-Positive T-Lymphocytes/metabolism , Glomerular Filtration Rate , Graft Rejection/etiology , Graft Rejection/pathology , Graft Survival , Immunosuppressive Agents/pharmacology , Kidney Failure, Chronic/surgery , Kidney Function Tests , Macaca mulatta , Postoperative Complications
4.
Am J Transplant ; 15(5): 1241-52, 2015 May.
Article in English | MEDLINE | ID: mdl-25702898

ABSTRACT

Islet xenotransplantation is a potential treatment for diabetes without the limitations of tissue availability. Although successful experimentally, early islet loss remains substantial and attributed to an instant blood-mediated inflammatory reaction (IBMIR). This syndrome of islet destruction has been incompletely defined and characterization in pig-to-primate models has been hampered by logistical and statistical limitations of large animal studies. To further investigate IBMIR, we developed a novel in vivo dual islet transplant model to precisely characterize IBMIR as proof-of-concept that this model can serve to properly control experiments comparing modified xenoislet preparations. WT and α1,3-galactosyltransferase knockout (GTKO) neonatal porcine islets were studied in nonimmunosuppressed rhesus macaques. Inert polyethylene microspheres served as a control for the effects of portal embolization. Digital analysis of immunohistochemistry targeting IBMIR mediators was performed at 1 and 24 h after intraportal islet infusion. Early findings observed in transplanted islets include complement and antibody deposition, and infiltration by neutrophils, macrophages and platelets. Insulin, complement, antibody, neutrophils, macrophages and platelets were similar between GTKO and WT islets, with increasing macrophage infiltration at 24 h in both phenotypes. This model provides an objective and internally controlled study of distinct islet preparations and documents the temporal histology of IBMIR.


Subject(s)
Inflammation/immunology , Islets of Langerhans Transplantation/methods , Islets of Langerhans/cytology , Animals , Animals, Genetically Modified , Blood Glucose/chemistry , Blood Platelets/immunology , Complement Activation , Disease Models, Animal , Galactosyltransferases/genetics , Immunohistochemistry , Macaca mulatta , Macrophages/immunology , Neutrophils/immunology , Phenotype , Swine , Time Factors , Transplantation, Heterologous
5.
Br J Surg ; 101(3): 172-88, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24469618

ABSTRACT

BACKGROUND: Enhanced recovery programmes (ERPs) have been developed over the past 10 years to improve patient outcomes and to accelerate recovery after surgery. The existing literature focuses on specific specialties, mainly colorectal surgery. The aim of this review was to investigate whether the effect of ERPs on patient outcomes varies across surgical specialties or with the design of individual programmes. METHODS: MEDLINE, Embase, CINAHL and the Cochrane Central Register of Controlled Trials were searched from inception to January 2013 for randomized or quasi-randomized trials comparing ERPs with standard care in adult elective surgical patients. RESULTS: Thirty-eight trials were included in the review, with a total of 5099 participants. Study design and quality was poor. Meta-analyses showed that ERPs reduced the primary length of stay (standardized mean difference -1Ā·14 (95 per cent confidence interval -1Ā·45 to -0Ā·85)) and reduced the risk of all complications within 30 days (risk ratio (RR) 0Ā·71, 95 per cent c.i. 0Ā·60 to 0Ā·86). There was no evidence of a reduction in mortality (RR 0Ā·69, 95 per cent c.i. 0Ā·34 to 1Ā·39), major complications (RR 0Ā·95, 0Ā·69 to 1Ā·31) or readmission rates (RR 0Ā·96, 0Ā·59 to 1Ā·58). The impact of ERPs was similar across specialties and there was no consistent evidence that elements included within ERPs affected patient outcomes. CONCLUSION: ERPs are effective in reducing length of hospital stay and overall complication rates across surgical specialties. It was not possible to identify individual components that improved outcome. Qualitative synthesis may be more appropriate to investigate the determinants of success.


Subject(s)
Medicine/statistics & numerical data , Postoperative Care/methods , Postoperative Complications/rehabilitation , Recovery of Function , Clinical Trials as Topic , Humans , Length of Stay , Patient Readmission/statistics & numerical data , Postoperative Care/mortality , Postoperative Complications/mortality , Research Design , Risk Factors
6.
Am J Transplant ; 13(2): 312-9, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23279640

ABSTRACT

Calcineurin inhibitors (CNI) and steroids are known to promote insulin resistance, and their avoidance after islet transplantation is preferred from a metabolic standpoint. Belatacept, a B7-specific mediator of costimulation blockade (CoB), is clinically indicated as a CNI alternative in renal transplantation, and we have endeavored to develop a clinically translatable, belatacept-based regimen that could obviate the need for both CNIs and steroids. Based on the known synergy between CoB and mTOR inhibition, we studied rhesus monkeys undergoing MHC-mismatched islet allotransplants treated with belatacept and the mTOR inhibitor, sirolimus. To extend prior work on CoB-resistant rejection, some animals also received CD2 blockade with alefacept (LFA3-Ig). Nine rhesus macaques were rendered diabetic with streptozotocin and underwent islet allotransplantation. All received belatacept and sirolimus; six also received alefacept. Belatacept and sirolimus significantly prolonged rejection-free graft survival (median 225 days compared to 8 days in controls receiving basiliximab and sirolimus; p = 0.022). The addition of alefacept provided no additional survival benefit, but was associated with Cytomegalovirus reactivation in four of six animals. No recipients produced donor-specific alloantibodies. The combination of belatacept and sirolimus successfully prevents islet allograft survival in rhesus monkeys, but induction with alefacept provides no survival benefit and increases the risk of viral reactivation.


Subject(s)
Immunoconjugates/administration & dosage , Islets of Langerhans Transplantation/methods , Recombinant Fusion Proteins/administration & dosage , Sirolimus/administration & dosage , Transplantation, Homologous/methods , Abatacept , Alefacept , Animals , Antibodies, Monoclonal/administration & dosage , Basiliximab , C-Peptide/metabolism , Diabetes Mellitus, Experimental , Graft Survival , Histocompatibility Antigens/immunology , Immunosuppressive Agents/administration & dosage , Islets of Langerhans/drug effects , Islets of Langerhans/immunology , Macaca mulatta , Steroids/administration & dosage
7.
Lymphology ; 45(2): 47-52, 2012 Jun.
Article in English | MEDLINE | ID: mdl-23057148

ABSTRACT

Plastic bronchitis is a rare condition characterized by the formation and expectoration of long, branching bronchial casts that develop in the tracheobronchial tree and cause airway obstruction. Plastic bronchitis has become increasingly recognized as a feared complication of the Fontan operation with a mortality of up to 50%. We report an 11 year old boy who developed severe plastic bronchitis following Fontan repair and the successful long-term control of cast formation utilizing a low-fat diet and subsequent thoracic duct ligation.


Subject(s)
Bronchitis/diet therapy , Diet, Fat-Restricted , Fontan Procedure/adverse effects , Thoracic Duct/surgery , Bronchitis/etiology , Bronchoscopy , Child , Combined Modality Therapy , Humans , Ligation , Male , Postoperative Complications , Prognosis
8.
Lymphology ; 55(2): 65-69, 2022.
Article in English | MEDLINE | ID: mdl-36170580

ABSTRACT

Plastic bronchitis, more appropriately termed chyloptysis, is a rare and potentially fatal condition caused by chylous coating of the airways. These cast coating can dislodge and become an obstructive mass in the patient's airway, necessitating rapid intervention. PB is well described to occur following single ventricle physiology heart disease corrective procedures, particularly following Fontan procedures. It is less commonly seen in traumatic settings. We present the youngest known case of a traumatic injury induced plastic bronchitis. A 19-year-old man was involved in a motor vehicle accident with airbag deployment. The airbags struck him in the chest; however, the patient felt well at the time and did not seek medical attention. Several months later the patient began coughing up milky white masses identified as casts. He was initially diagnosed with asthma but did not respond to therapy. He ultimately was found to have evidence of thoracic duct injury. Options for therapy were discussed, including possible thoracic duct ligation. The patient opted to continue a lowfat diet and has remained cast free. This case highlights the importance of considering plastic bronchitis in patients with cast production and a history of trauma to the chest.


Subject(s)
Bronchitis , Fontan Procedure , Adult , Bronchitis/diagnosis , Bronchitis/etiology , Bronchitis/therapy , Fontan Procedure/adverse effects , Humans , Male , Motor Vehicles , Plastics , Thoracic Duct/surgery , Young Adult
9.
J Natl Cancer Inst ; 54(4): 819-24, 1975 Apr.
Article in English | MEDLINE | ID: mdl-236393

ABSTRACT

Tissue sections from human placentas taken at term were studied after time-sequential incubations with benzo[a]pyrene and appropriate cofactors for mixed-function oxidation. Fluorescence microscopy revealed that the enzymic reaction appeared to be most active in the syncytial trophoblast, though the fluorescence of hydroxylated metabolites also could be observed in other placental cell types. A comparison of sections from placentas with very low versus very high aryl hydrocarbon hydroxylase activities provided evidence that induction of the human placental enzyme system with pol7cyclic aromatic hydrocarbons also appeared to occur primarily in the syncytium. When considered in conjunction with previous studies on human placental aryl hydrocarbon hydroxylase, the results tended to indicate that fetal elements of the human placenta contain the necessary electron-transport components for catalysis of mixed-function oxidations of chemical carcinogens and other foreign compounds and that this hydroxtlase system is readily inducible in the same fetal cells by components present in cigarette smoke.


Subject(s)
Aryl Hydrocarbon Hydroxylases/metabolism , Placenta/enzymology , Benzopyrenes , Enzyme Induction , Histocytochemistry , Humans , Microscopy, Fluorescence , NAD , NADP , Trophoblasts/enzymology
10.
J Natl Cancer Inst ; 70(2): 337-42, 1983 Feb.
Article in English | MEDLINE | ID: mdl-6337293

ABSTRACT

The immunocytochemical localization of catechol methyltransferase was determined in normal and cancerous breast tissues of inbred female Swiss-Webster mice and in normal, lactating, and cancerous breast tissues of inbred Sprague-Dawley rats. The enzyme was found to be cytoplasmically localized in ductal epithelial cells of secretory tubules in both inactive and stimulated mammary glands, in endothelial cells lining blood vessels, in fibroblasts in the connective tissue matrix, and, especially, in tumor cells. Adipose cells were nonreactive. The intensity of the immunocytochemical reaction in tumor cells was stronger than that in lactating tissues, which, in turn, was more reactive than that in normal, unstimulated breast tissues.


Subject(s)
Catechol O-Methyltransferase/analysis , Adenocarcinoma/enzymology , Adipose Tissue/enzymology , Animals , Cytoplasm/enzymology , Epithelium/enzymology , Female , Fibroblasts/enzymology , Histocytochemistry , Immunologic Techniques , Lactation , Mammary Neoplasms, Experimental/enzymology , Mice , Mice, Inbred Strains , Pregnancy , Rats , Rats, Inbred Strains
11.
Cancer Chemother Pharmacol ; 5(1): 61-5, 1980.
Article in English | MEDLINE | ID: mdl-7460195

ABSTRACT

Chemotherapeutic usefulness of adriamycin (ADR) and daunomycin (DAU), members of a large class of antitumor anthracyclines, is limited by a unique cardiotoxicity. Using spontaneously beating isolated myocytes from adult rat hearts, we have observed a relatively unique effect of these agents upon maximal contraction times. ADR and DAU induce cessation of beating in an identical dose-dependent manner, while two related anthracyclines exhibit similar inhibitory effects but at different concentrations. Other cytotoxic and antitumor agents tested failed to significantly affect maximal contraction times. This system may be useful in the evaluation of anthracycline analogs for cardiotoxic potential relative to ADR and DAU, as well as in studying the mechanisms of that toxicity. It may also prove useful in selective examination of the direct effects of other agents upon myocardial cells.


Subject(s)
Daunorubicin/administration & dosage , Doxorubicin/administration & dosage , Myocardial Contraction/drug effects , Myocardium/cytology , Animals , Cells, Cultured , Daunorubicin/analogs & derivatives , Depression, Chemical , Dose-Response Relationship, Drug , Doxorubicin/analogs & derivatives , Drug Evaluation, Preclinical , Humans , Male , Rats
12.
Article in English | MEDLINE | ID: mdl-4067835

ABSTRACT

The effects of toxic doses of various drugs and of food or water deprivation upon heart weights of mice were evaluated over a four day period to test the validity of the hypothesis that changes in cardiac weights are indicators of cardiotoxicity. Drugs included in the study were actinomycin-D, methotrexate, 5-fluorouracil, adriamycin, daunomycin, N-dimethyladriamycin, N-trifluoroacetyladriamycin-14-valerate, isoproterenol, atropine, and acetylsalicylic acid. Additional groups of mice served as vehicle controls, or were deprived of food or water for the duration of the experiment to control for the anorexia and dehydration accompanying treatment with antineoplastic drugs. Body weights were taken at the start of the experiment (day 0), day 2, and day 4 (just prior to sacrifice). Heart ventricle wet weights were determined immediately, and dry weights after thorough desiccation of the samples. Statistical evaluation of the weights revealed that there were no ventricular weight changes unique to any particular drug, and that decreases in heart weights correlated well with decreases in body weights, thereby reflecting the general toxicities of the drugs, including inanition, and not any specific cardiotoxicities.


Subject(s)
Antibiotics, Antineoplastic/toxicity , Heart Diseases/chemically induced , Heart/drug effects , Animals , Body Weight/drug effects , Doxorubicin/toxicity , Heart Diseases/diagnosis , Heart Ventricles/drug effects , Male , Mice , Organ Size/drug effects , Time Factors
13.
Am Surg ; 61(3): 197-201, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7887528

ABSTRACT

This study was done to investigate whether laparoscopic intracorporeal (LI) or laparoscopic assisted (LA) colon resection results in improved anastomotic healing compared with open colon resection (OR). Thirty-six domestic swine were randomly assigned to undergo either LI, LA, or OR of the rectosigmoid. For OR cases, the sigmoid was resected through a midline incision, and a transanal end-to-end stapled anastomosis was constructed with an ILS device. For LA and LI cases, the sigmoid was laparoscopically mobilized and divided distally, using 5 trocar sites. For LA cases, the proximal sigmoid was brought out through an enlarged trocar site and resected; the ILS anvil was secured to the proximal end, and the colon was replaced in the abdominal cavity where the anastomosis was completed by transanal insertion and firing of ILS device. For LI cases, the sigmoid was resected laparoscopically and retrieved through a 33 mm trocar. The ILS anvil was introduced via the same trocar, and the device was laparoscopically secured with two Endoloop (Ethicon Endo-Surgery, Cincinnati, OH) pursestring sutures. The anastomosis was completed the same way as for LA cases. Animals were killed at 7 days, at which time the anastomoses were evaluated by barium enema, bursting pressure, and histologic appearance. There were no radiographic anastomotic leaks. The mean bursting pressure was 205 +/- 65 mmHg for the 13 OR animals, 240 +/- 53 mmHg for 11 LA animals, and 242 +/- 43 mmHg for the 12 LI animals (N.S.). Histologic evaluation for inflammation indicated no significant differences.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Colon/surgery , Laparoscopy/methods , Anastomosis, Surgical , Animals , Colon/physiopathology , Male , Methods , Postoperative Complications , Random Allocation , Swine , Tensile Strength , Time Factors
15.
J Pharmacol Exp Ther ; 194(3): 522-36, 1975 Sep.
Article in English | MEDLINE | ID: mdl-1159629

ABSTRACT

Monoamine oxidase (MAO) increases in an age-weight relationship in the hearts of male rats. Accumulation of MAO is not related to the activities of such mitochondrial enzymes as succinic dehydrogenase or cytochrome oxidase which do not change with age. Our previous experiments, utilizing serotonin as a substrate, have determined that cardiac MAO in the young rat does not change after chemical sympathetectomy with 6-hydroxydopamine. In this study, rats of different ages were treated with 6-hydroxy-dopamine to investigate the neuronal vs. non-neuronal distribution of MAO in the heart. After sympathetectomy, various parts of the hearts and fractions of the hearts isolated by differential centrifugation were tested for changes in MAO activity with two different substrates (kynuramine and 14C-tryptamine). It was not possible to detect any changes in MAO activity in any parts or subcellular fractions of the heart as a result of denervation. Studies with clorgyline, the MAO inhibitor, in control and sympathetecomized animals revealed that rat cardiac MAO is mostly of the type A enzyme, which was originally thought to be neuronal. A histochemical technique for the electron microscopic demonstration of MAO with osmiophilic thiocarbamyl nitro blue tetrazolium was used in the rat heart in order to determine the ultrastructural location of the enzyme. Histochemical localization of MAO with the electron microscope using tryptamine as the substrate indicates that a substantial portion of rat cardiac MAO is located near the outer membranes of mitochondria within myocardial cells. This histochemical technique provides no evidence to support differential centrifugation data which suggests the presence of a sarcoplasmic reticular (microsomal) MAO in rat heart.


Subject(s)
Monoamine Oxidase/metabolism , Myocardium/enzymology , Aging , Animals , Hydroxydopamines/pharmacology , In Vitro Techniques , Kynuramine/metabolism , Male , Microscopy, Electron , Muscle Proteins/metabolism , Myocardium/ultrastructure , Neurons/enzymology , Norepinephrine/metabolism , Rats , Serotonin/metabolism , Subcellular Fractions/enzymology , Sympathectomy , Tryptamines/metabolism
16.
Gastroenterology ; 73(2): 327-38, 1977 Aug.
Article in English | MEDLINE | ID: mdl-873134

ABSTRACT

A 15-year-old girl with idiopathic intestinal pseudoobstruction is reported. She presented with a long term history of low grade obstructive symptoms, diarrhea, and poor nutrition culminating in an acute obstructive attack leading to exploratory laparotomy. At surgery, the small bowel and colon were dilated, with no mechanical obstruction found. Further evaluation revealed her to have a diffuse disorder of gastrointestinal smooth muscle function involving esophagus, small bowel, and colon. Because medical management failed to control symptom, a gastrojejunostomy was done to bypass a megaduodenum. A third laparotomy was necessary 2 months later because of intractable obstructive symptoms. At this last laparotomy, the afferent loop was taken down and a duodenoplasty and duodenojejunostomy were performed, resulting in clinical improvement. Light and electron microscopic study of the excised small intestine showed marked thinning and degeneraton of the smooth muscle, with replacement by fibrous tissue. The myenteric plexus was normal. This case demonstrates that a degenerative disease of smooth muscle may be one cause of idiopathic intestinal pseudoobstruction.


Subject(s)
Intestinal Diseases , Intestinal Obstruction/diagnosis , Intestine, Small/pathology , Muscle, Smooth/pathology , Adolescent , Biopsy , Dilatation, Pathologic , Female , Humans , Intestinal Diseases/diagnosis , Intestinal Diseases/diagnostic imaging , Intestinal Diseases/pathology , Intestinal Obstruction/diagnostic imaging , Intestine, Small/ultrastructure , Muscle, Smooth/ultrastructure , Radiography
17.
Oncology ; 40(5): 340-3, 1983.
Article in English | MEDLINE | ID: mdl-6621996

ABSTRACT

A study of the cardiotoxicity induced by adriamycin (ADR) was done on the heart tissue of Sprague-Dawley rats receiving a single intravenous dose (15 mg/kg). Condensed bright orange-red fluoresced chromatin was observed in the nuclei of the myocardial cells of the left ventricle 2 h after drug injection. Just then, the intensity of the fluorescence emission started to decrease until it reached its minimum after 21 days, and disappeared completely 28 days after drug injection.


Subject(s)
Doxorubicin/metabolism , Myocardium/metabolism , Animals , Binding Sites , Male , Microscopy, Fluorescence , Rats , Rats, Inbred Strains , Time Factors
18.
Eur J Biochem ; 120(1): 129-36, 1981 Nov.
Article in English | MEDLINE | ID: mdl-6273166

ABSTRACT

Interactions of both purified tubulin and microtubule protein (tubulin plus associated proteins) with two commonly used sulfonate buffers were examined. 1,4-Piperazineethanesulfonate (Pipes) and 4-morpholineethanesulfonate (Mes) at high concentrations induce the polymerization of purified tubulin in reactions requiring only buffer, tubulin and GTP. While both reactions were temperature-dependent, cold-reversible and inhibited by GDP, colchicine or Ca2+, there were significant differences between them. Substantially lower tubulin and buffer concentrations were required for Pipes-induced polymerization; and turbidity was much more intense in the Pipes-induced than in the Mes-induced reaction at the same protein concentration. Electron microscopy demonstrated that for the most part typical smooth-walled microtubules were formed in Mes, while aberrant forms were the predominant structures formed in Pipes. When the polymerization of microtubule protein was examined as a function of buffer concentration, biphasic patterns were observed with both Pipes and Mes: polymerization occurred at both low and high, but not intermediate, buffer concentrations. The turbidity observed at high concentrations of Pipes greatly exceeded that at low concentrations. With Mes, equivalent turbidity developed at both high and low buffer concentrations. Although associated proteins copolymerized with tubulin at low buffer concentrations, they were excluded from the polymerized material at high buffer concentrations. Pipes and Mes were compared to sodium phosphate, Tris/HCl and imidazole/HCl buffers at 0.1 M in several polymerization systems using both purified tubulin and microtubule protein. The sulfonate buffers were invariably associated with more vigorous reactions than the other buffers.


Subject(s)
Alkanesulfonates/pharmacology , Alkanesulfonic Acids , Buffers , Morpholines/pharmacology , Piperazines/pharmacology , Tubulin/metabolism , Calcium/pharmacology , Colchicine/pharmacology , Guanosine Diphosphate/pharmacology , Magnesium/pharmacology , Microtubules/metabolism , Polymers , Temperature
19.
Biochem Biophys Res Commun ; 110(2): 675-81, 1983 Jan 27.
Article in English | MEDLINE | ID: mdl-6838545

ABSTRACT

The acute toxic effects of 1,1-dichloroethylene (DCE; 125 mg/kg, i.p.) on mouse lung, liver and kidney were investigated 24 hr after its administration. DCE caused a reduction of cytochrome P-450 levels and related monooxygenases in lung microsomes with no corresponding changes in liver and kidney. Examination of the lung tissue by light microscopy revealed necrosis restricted to the Clara cells. In contrast, liver and kidney were relatively unaffected by DCE treatment, as indicated by lack of changes in microsomal monooxygenase activities and morphology.


Subject(s)
Dichloroethylenes/toxicity , Hydrocarbons, Chlorinated/toxicity , Lung/pathology , Oxygenases/antagonists & inhibitors , Animals , Cytochrome P-450 Enzyme System , Kidney/drug effects , Kidney/pathology , Liver/drug effects , Liver/pathology , Lung/drug effects , Male , Mice , Mice, Inbred C57BL , Microsomes, Liver/enzymology
20.
Cancer Treat Rep ; 66(1): 157-61, 1982 Jan.
Article in English | MEDLINE | ID: mdl-7053251

ABSTRACT

Doxorubicin was administered to rats in a simulated "belly bath" protocol. Fifty milliliters of various concentrations of drug solution was administered ip and was allowed to remain in situ for either 4 or 36 hours prior to removal. Animals were analyzed at 2, 14, and 60 days after treatment. Doses ranged from lethal (75 and 150 micrograms/ml for 4 hours; 12 and 24 micrograms/ml for 36 hours) to nontoxic (5 micrograms/ml for 4 hours). The most common lesion in surviving animals was chronic fibrosing peritonitis. Grossly, there were large volumes of peritoneal fluid in animals exposed to low concentrations (12 and 24 micrograms/ml) for 36 hours, but peritoneal adhesions were the most commonly observed finding when higher concentrations (20-150 micrograms/ml) were used for 4 hours. Commonly observed systemic toxic effects (bone marrow, gastrointestinal tract, and heart) were not seen in this study. Vehicle-treated control animals were negative for all histologic lesions and gross observations.


Subject(s)
Doxorubicin/administration & dosage , Animals , Dose-Response Relationship, Drug , Doxorubicin/toxicity , Female , Injections, Intraperitoneal , Peritonitis/chemically induced , Rats , Rats, Inbred Strains
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