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1.
Water Resour Res ; 57(10): e2020WR028946, 2021 Oct.
Article in English | MEDLINE | ID: mdl-35860362

ABSTRACT

Human and ecological health have been threatened by the increase of cyanobacteria harmful algal blooms (cyanoHABs) in freshwater systems. Successful mitigation of this risk requires understanding the factors driving cyanoHABs at a broad scale. To inform management priorities and decisions, we employed random forest modeling to identify major cyanoHAB drivers in 369 freshwater lakes distributed across 15 upper Midwest states during the 2011 bloom season (July-October). We used Cyanobacteria Index (CI_cyano)-A remotely sensed product derived from the MEdium Resolution Imaging Spectrometer (MERIS) aboard the European Space Agency's Envisat satellite-as the response variable to obtain variable importance metrics for 75 landscape and lake physiographic predictor variables. Lakes were stratified into high and low elevation categories to further focus CI_cyano variable importance identification by anthropogenic and natural influences. "High elevation" watershed land cover (LC) was primarily forest or natural vegetation, compared with "low elevation" watersheds LC dominated by anthropogenic landscapes (e.g., agriculture and municipalities). We used the top ranked 25 Random Forest variables to create a classification and regression tree (CART) for both low and high elevation lake designations to identify variable thresholds for possible management mitigation. Mean CI_cyano was 3 times larger for "low elevation" lakes than for "high elevation" lakes, with both mean values exceeding the "High" World Health Organization recreational guidance/action level threshold for cyanobacteria (100,000 cells/mL). Agrarian-related variables were prominent across all 369 lakes and low elevation lakes. High elevation lakes showed more influence of lakeside LC than for the low elevation lakes.

2.
Childs Nerv Syst ; 36(3): 491-496, 2020 03.
Article in English | MEDLINE | ID: mdl-31179530

ABSTRACT

PURPOSE: Though the use of the pedicled nasoseptal flap (NSF), a reconstructive technique used after endoscopic endonasal approaches (EEA) for resection of craniopharyngiomas, has been shown to reduce the occurrence of post-operative cerebrospinal fluid (CSF) leaks in adults, less is known about its use in pediatric populations, specifically in children under the age of 7. The goal of this retrospective cohort study is to determine the viability of the pedicled NSF for pediatric patients. METHODS: Retrospective review of 12 pediatric patients (ages 2-16) undergoing 13 NSF reconstructions after resection of craniopharyngiomas. Radioanatomic analysis of computed tomography (CT) scans was utilized to classify the pneumatization of the sphenoid sinus depending on the thickness of the sphenoid bone margin. Intercarotid distances were measured from magnetic resonance imaging (MRI) scans to assess the feasibility of this reconstruction technique in pediatric patients. RESULTS: At the time of surgery, all patients were noted to have adequate NSF length and width. No post-operative high-flow CSF leaks were found within the group. Lack of pneumatization of the sphenoid sinus and narrow intercarotid distances in the youngest of patients did not lead to negative clinical outcomes. CONCLUSIONS: Based on our results and experience, the pedicled nasoseptal flap is a viable reconstructive option after EEA in the pediatric population, including even the youngest of patients. In these patients, a narrowed window between the intercarotid arteries and the lack of pneumatization of the sphenoid sinus present a challenge that can be overcome by using stereotactic navigation and advanced endoscopic techniques.


Subject(s)
Craniopharyngioma , Pituitary Neoplasms , Plastic Surgery Procedures , Adolescent , Adult , Child , Child, Preschool , Craniopharyngioma/diagnostic imaging , Craniopharyngioma/surgery , Endoscopy , Humans , Pituitary Neoplasms/diagnostic imaging , Pituitary Neoplasms/surgery , Retrospective Studies , Skull Base/diagnostic imaging , Skull Base/surgery , Surgical Flaps
3.
Surg Neurol Int ; 9: 100, 2018.
Article in English | MEDLINE | ID: mdl-29900030

ABSTRACT

BACKGROUND: Amyloidosis encompasses a group of disorders sharing the common feature of intercellular deposition of amyloid protein by several different pathogenetic mechanisms. Primary solitary amyloidosis, or amyloidoma, is a rare subset of amyloidosis in which amyloid deposition is focal and not secondary to a systemic process or plasma cell dyscrasia. CASE DESCRIPTION: This 84-year-old female presented with history of multiple syncopal episodes, dysphagia, and ataxia. Motor strength was 3+/5 in the right upper extremity. Rheumatoid factor, cyclic citrullinated peptide (CCP), and anti-nuclear antibody (ANA) were normal. Serum and urine immune-electrophoresis detected no abnormal bands. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated a non-enhancing soft-tissue mass extending from the retro-clivus to C2 posteriorly, eccentric to the right with severe mass effect on the upper cervical medullary junction. Endoscopic trans-nasal debulking of the retro-clival mass was performed with occiput to C5 posterior instrumentation for spinal stabilization. CONCLUSIONS: Primary solitary amyloidosis, unlike other forms of amyloidosis, has an excellent prognosis with local resection. Diagnosis requires special stains and a degree of suspicion for the disease. This is the first report to document an endoscopic trans-nasal approach for removal of a primary solitary amyloidosis of the retro-clivus. Management of vertebral amyloidoma involves aggressive local resection of the tumor when feasible and spine stabilization as the degree of tumor involvement mandates. Complete evaluation for the diagnosis of systemic amyloidosis is essential for the management and prognostication. Surgeons encountering such lesions must maintain high suspicion for this rare disease and advise pathologists accordingly to establish the correct diagnosis.

4.
Int Forum Allergy Rhinol ; 1(6): 460-5, 2011.
Article in English | MEDLINE | ID: mdl-22144055

ABSTRACT

BACKGROUND: To report outcomes for subjects undergoing balloon dilation in either the operating room (OR) or the clinic and define criteria to identify suitable candidates for local anesthesia procedures. METHODS: Subjects with medically refractory chronic rhinosinusitis (CRS) underwent de novo surgery via transantral balloon dilation of the maxillary sinus ostium and ethmoid infundibulum. Concomitant nasal or endoscopic sinus surgeries were contraindicated. Technical success, surgical parameters, and long-term outcomes were evaluated through 12-month follow-up. RESULTS: Seventy-one subjects underwent balloon dilation and 94% completed follow-up through 12 months. A total of 132 maxillary ostia were targeted for treatment and 129 were successfully dilated (98%). Almost one-half (33) of the procedures were performed in the OR under local anesthesia with intravenous sedation. Average balloon procedure times for unilateral and bilateral treatment were 28.3 ± 21.1 and 40.2 ± 17.7 minutes, respectively. Thirty-three ostial dilations in 19 subjects were attempted in the clinic. Each ostium was successfully accessed and ballooned under local anesthesia. Patient tolerance was very good with an average self-reported pain level of 2.7 (2 = hurts a little bit) out of 10. Each subject was discharged within 2 hours of the procedure and there was no postoperative bleeding. Symptomatic improvement of the clinic subgroup at 3, 6, and 12 months postprocedure was statistically significant (p ≤ 0.0012) and clinically meaningful and similar in magnitude to improvement seen across all subjects regardless of site of service. CONCLUSION: Transantral balloon dilation can be performed safely in the clinic and operative settings with symptom improvement sustained through 1 year.


Subject(s)
Catheterization/methods , Ethmoid Sinus , Maxillary Sinus , Rhinitis/therapy , Sinusitis/therapy , Adult , Anesthesia, Local , Chronic Disease , Female , Humans , Male , Middle Aged , Patient Selection , Prospective Studies , Treatment Outcome
5.
Int Forum Allergy Rhinol ; 1(1): 38-45, 2011.
Article in English | MEDLINE | ID: mdl-22287306

ABSTRACT

BACKGROUND: Although multiple clinical trials have demonstrated that balloon dilation of sinus ostia in patients diagnosed with chronic rhinosinusitis (CRS) results in sustained symptomatic improvement, less data are available to measure the effects of sinusitis on worker productivity. The objective of our research was to analyze work and activity impairment before and after transantral, endoscopically-guided balloon dilation of the maxillary sinus ostia and ethmoid infundibulum. METHODS: Subjects diagnosed with CRS and computed tomography (CT) evidence of disease in the maxillary sinuses alone, or maxillary and anterior ethmoid sinuses, completed the Work Productivity and Activity Impairment (WPAI) questionnaire and the Work Limitation Questionnaire (WLQ) before treatment and at 3, 6, and 12 months postprocedure. RESULTS: A total of 56 subjects were enrolled and 53 completed the 1-year follow-up. The lost productivity composite score computed from the WLQ improved by 73% (9.0 to 2.4; p < 0.0001) at 1-year follow-up whereas lost productivity at work as measured by the WPAI improved by approximately 76% (38.3 to 9.2; p < 0.0001) 12 months after treatment. CONCLUSION: These results indicate that sinus-related health problems impose a substantial burden on work productivity and physical/mental activity levels. Treatment of CRS by dilating the maxillary sinus ostium and ethmoid infundibulum can significantly improve quality of life (QOL) and work productivity.


Subject(s)
Catheterization/methods , Ethmoid Sinusitis/therapy , Maxillary Sinusitis/therapy , Occupational Diseases/therapy , Rhinitis/therapy , Absenteeism , Adult , Chronic Disease , Efficiency , Employment/statistics & numerical data , Endoscopy , Ethmoid Sinusitis/physiopathology , Humans , Maxillary Sinusitis/physiopathology , Middle Aged , Occupational Diseases/physiopathology , Physical Fitness , Prospective Studies , Quality of Life , Rhinitis/physiopathology , Surveys and Questionnaires , Task Performance and Analysis , Treatment Outcome
6.
Biochim Biophys Acta ; 1774(1): 154-67, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17174161

ABSTRACT

Prion-induced neurodegeneration results from multiple cellular alterations among which the accumulation of a modified form of the host protein PrP is but a hallmark. Drug treatments need understanding of underlying mechanisms. Proteomics allows getting a comprehensive view of perturbations leading to neuronal death. Heparan sulfate mimetics has proved to be efficient to clear scrapie protein in cultured cells and in animals. To investigate the mechanisms of drug attack, protein profiles of the neuronal cell line GT1 and its chronically Chandler strain infected counterpart were compared, either in steady state cultures or after a 4-day drug treatment. Differentially expressed proteins were associated into functional blocks relevant to neurodegenerative diseases. Protein structure repair and modification, proteolysis, cell shape and energy/oxidation players were affected by infection, in agreement with prion biology. Unexpectedly, novel affected blocks related to translation, nucleus structure and DNA replication were unravelled displaying commonalities with proliferative processes. The drug had a double action in infected cells by reversing protein levels back to normal in some blocks and by heightening survival functions in others. This study emphasizes the interest of a proteomic approach to unravel novel networks involved in prion infection and curing.


Subject(s)
PrPSc Proteins/antagonists & inhibitors , Prion Diseases/physiopathology , Proteomics , Animals , Anti-Infective Agents , Cell Line , Gene Expression Profiling , Heparitin Sulfate/therapeutic use , Mice , Nerve Tissue Proteins/analysis , Neurons , Prion Diseases/drug therapy , Scrapie/drug therapy , Scrapie/physiopathology
8.
Arch Facial Plast Surg ; 2(4): 264-8, 2000.
Article in English | MEDLINE | ID: mdl-11074722

ABSTRACT

OBJECTIVE: To describe a modified technique of liposuction that combines endoscopic techniques and a soft tissue shaver for neck recontouring. DESIGN: Nonrandomized, nonblinded, retrospective evaluation of endoscopic liposhaving for patients requiring neck recontouring in a facial plastic surgery practice. INTERVENTIONS: Endoscopic liposhaving was performed on 5 patients undergoing neck recontouring with platysma plication using a small submental incision. MAIN OUTCOME MEASURES: Subjective evaluation by the surgeon. RESULTS: Direct visualization with the endoscope ensures complete removal of excess fat while maintaining a small amount of fat over the platysma muscle and on the skin flap. The fat was easily and precisely removed with minimal trauma and edema. There were no resulting facial nerve injuries, dimpling, hematomas, or significant asymmetries. CONCLUSIONS: Endoscopic liposhaving for neck recontouring is a precise and less traumatic method of lipectomy than the current techniques. Direct fat visualization with an endoscope allows more accuracy than the external visualization and palpation relied on in conventional liposuction or direct liposhaving. Using these 2 newer modalities can lead to quicker recovery time. There are no known previous reports of use of these 2 techniques together. Arch Facial Plast Surg. 2000;2:264-268


Subject(s)
Endoscopy/methods , Lipectomy/methods , Neck/surgery , Rhytidoplasty/methods , Combined Modality Therapy , Endoscopy/adverse effects , Humans , Lipectomy/adverse effects , Lipectomy/instrumentation , Retrospective Studies , Rhytidoplasty/instrumentation , Treatment Outcome
9.
J Endocrinol ; 161(2): 289-98, 1999 May.
Article in English | MEDLINE | ID: mdl-10320827

ABSTRACT

We report the ability of sheep placental cotyledonary cells, isolated at different periods of pregnancy (40 to 90 days) to produce ovine chorionic somatomammotrophin (oCS) in in vitro culture conditions. This oCS production increased gradually with stage of pregnancy. Endogenous oCS net production by isolated placental cells was increased, in a dose-dependent manner, by addition of recombinant oCS (roCS). This effect was not observed after addition of recombinant ovine growth hormone. The roCS effect was more potent on cells collected during early pregnancy. Specific immunoprecipitation of oCS revealed that roCS treatment was associated with an increased dose-dependent incorporation of [35S]methionine-[35S]cysteine. These findings provide evidence that oCS may act in a paracrine/autocrine manner to up-regulate its own production during early gestation. We suggest that this autoregulation may be associated with morphological and functional differentiation of the trophoblast during the growth of the placenta.


Subject(s)
Homeostasis/physiology , Placenta/metabolism , Placental Lactogen/biosynthesis , Pregnancy, Animal/metabolism , Sheep/metabolism , Animals , Blotting, Northern , Cell Culture Techniques , Cysteine/metabolism , Female , Gene Expression , Growth Hormone/pharmacology , Methionine/metabolism , Placenta/cytology , Placenta/drug effects , Placental Lactogen/genetics , Placental Lactogen/pharmacology , Pregnancy , RNA, Messenger/genetics , Recombinant Proteins/pharmacology
10.
Mutat Res ; 425(1): 29-46, 1999 Mar 10.
Article in English | MEDLINE | ID: mdl-10082914

ABSTRACT

Cooking meat and fish at high temperature creates heterocyclic amines (HA) including 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Several HA are mutagens in the Ames' S9/Salmonella assay. While PhIP is a substantial Ames' test mutagen, it is 1000-fold less active than the extraordinarily potent MeIQ. In contrast, MeIQ is significantly less mutagenic than PhIP in several mammalian cell assays, especially in repair-deficient Chinese hamster ovary (CHO) cells. HA are suspect human carcinogens on the basis of (i) epidemiological evidence, (ii) induction of tumors in rodents and monkeys, (iii) DNA adduct formation and (iv) mutagenic capacity. In this study, MeIQ and PhIP were significant mutagens at the S1 locus of co-cultivated human/hamster hybrid AL cells following metabolic activation by beta-napthoflavone (betaNF)-induced chick embryonic liver cultures (CELC). MeIQ was more mutagenic than PhIP in the CELC+AL cell assay. The mutant response curves increase with dose and then plateau (PhIP), or decrease (MeIQ). The inflections in these response curves coincide with dose-dependent decreases in cytochrome CYP1A1 activity. Molecular analysis of S1- mutants indicates that a substantial fraction, >65%, of the mutations induced by PhIP are deletions of 4.2 to 133 (Mbp); half are larger than 21 Mbp. Mutations induced by MeIQ were smaller, most (56%) being less than 5.7 Mbp. When appropriate metabolic activation is combined with a target locus, which can detect both small and large chromosomal mutations, both MeIQ and PhIP are significant mutagens and clastogens in repair proficient mammalian cells.


Subject(s)
Imidazoles/toxicity , Mutagens/toxicity , Quinolines/toxicity , Animals , Biotransformation , Chick Embryo , Coculture Techniques , Cricetinae , Humans , Hybrid Cells , Imidazoles/pharmacokinetics , Mutagens/pharmacokinetics , Mutation , Quinolines/pharmacokinetics , beta-Naphthoflavone/pharmacology
11.
J Neurosurg ; 87(4): 508-11, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9322840

ABSTRACT

Patients undergoing brain tumor surgery are at high risk for the occurrence of a thromboembolic event. To identify a laboratory marker suitable for risk estimation the authors studied the perioperative time pattern of routine coagulation parameters and the specific hemostasis activation marker D-dimer in 28 consecutive patients at high risk (11 patients with glioma and eight patients with meningioma) and low risk (nine patients with metastases) for thromboembolism, as previously reported. As is typical during major surgery, most of the routine parameters declined, probably because of hemodilution, and recovered postoperatively to values higher than baseline, probably because of an acute-phase reaction. On Days 2 and 7 after surgery no difference in the routine parameters was recorded between patients at high (meningioma and glioma) and low risk (metastasis). The level of D-dimer was elevated at baseline in patients with metastasis, indicating a hemostatic hyperactivity that is usual in cancer patients. During surgery a marked increase in D-dimer levels occurred in patients with meningioma and glioma (pre- and postoperative median 90/2000 and 100/1020 ng/ml, respectively), but the increase was less pronounced in patients with metastasis (320/660 ng/ml). Postoperatively, D-dimer declined in patients with metastases to lower than preoperative levels (Day 7, 270 ng/ml); in patients with meningioma or glioma, however, D-dimer levels remained elevated until Day 7 (450 and 200 ng/ml, respectively). These results indicate that levels of D-dimer correlate with the reported high risk for thromboembolism in patients with meningioma and glioma, and D-dimer should be evaluated for its use in estimating individual risk and the efficiency of its use in the control of prophylactic treatment.


Subject(s)
Brain Neoplasms/surgery , Hemostasis/physiology , Acute-Phase Reaction/blood , Anticoagulants/therapeutic use , Antifibrinolytic Agents/blood , Biomarkers/blood , Blood Coagulation Tests , Brain Neoplasms/blood , Brain Neoplasms/physiopathology , Brain Neoplasms/secondary , Female , Fibrin Fibrinogen Degradation Products/analysis , Follow-Up Studies , Glioma/blood , Glioma/physiopathology , Glioma/surgery , Hemodilution , Heparin, Low-Molecular-Weight/therapeutic use , Humans , Intraoperative Care , Male , Meningioma/blood , Meningioma/physiopathology , Meningioma/surgery , Middle Aged , Risk Factors , Thromboembolism/blood , Thromboembolism/etiology , Thromboembolism/prevention & control
12.
Am J Pathol ; 145(3): 696-701, 1994 Sep.
Article in English | MEDLINE | ID: mdl-8080049

ABSTRACT

c-K-ras is activated by mutation at codon 12 in the majority of human pancreatic carcinomas of ductal but not acinar phenotype. The Ela-1-myc transgene when expressed in transgenic mice induces pancreatic carcinomas of both acinar and mixed acinar/ductal phenotype. The histopathology of 110 pancreatic carcinomas were characterized in this model. A high percentage of the low to moderately differentiated acinar cell carcinomas contain areas of ductal metaplasia. The latter tumors and several well-differentiated acinar tumors were evaluated for c-K-ras mutation to determine whether there is a relationship between the ductal phenotype and c-K-ras mutation. The polymerase chain reaction and allele-specific oligomer hybridization were used to determine whether the c-K-ras gene was mutated at codons 12, 13, or 61. Amplified DNA products from these tumors were also evaluated by single strand conformation polymorphism analysis. Only wild-type c-K-ras was found in these tissues. Not finding c-K-ras mutation in tumors containing ductal morphology indicates that c-K-ras mutation is not a required factor for acinar to ductal metaplasia or a factor in the tumorigenesis of pancreatic tumors that arise in acinar tissue.


Subject(s)
Carcinoma, Acinar Cell/genetics , Carcinoma, Ductal, Breast/genetics , Genes, ras/genetics , Mutation/genetics , Neoplasms, Multiple Primary/genetics , Pancreatic Neoplasms/genetics , Animals , Base Sequence , Carcinoma, Acinar Cell/pathology , Carcinoma, Ductal, Breast/pathology , Mice , Mice, Transgenic , Molecular Sequence Data , Neoplasms, Multiple Primary/pathology , Pancreatic Neoplasms/pathology
13.
Pancreas ; 9(2): 161-5, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8190717

ABSTRACT

The objective of this study was to determine whether small human pancreatic adenocarcinomas contain activated c-K-ras as an approach to answering the question of whether c-K-ras mutation is an early change in this disease. Eight pancreatic adenocarcinomas in the range 1.2-3 cm were analyzed for c-K-ras mutation at codon 12 by amplifying the c-K-ras gene around codon 12 out of paraffin-embedded tissue sections using the polymerase chain reaction. c-K-ras mutations were detected by allele-specific oligonucleotide hybridization. Six of the eight small pancreatic adenocarcinomas contained mutated c-K-ras at codon 12, position 2, and two of the six tumors had an additional mutation at position 1 of codon 12. Our results indicate that small pancreatic adenocarcinomas are similar to large, late-stage pancreatic adenocarcinomas in that 75% of the tumors analyzed contain mutated c-K-ras at codon 12, position 2. These data suggest that c-K-ras mutation occurs early and may therefore have a role in initiation of human pancreatic adenocarcinoma.


Subject(s)
Adenocarcinoma/genetics , Genes, ras , Mutation , Pancreatic Neoplasms/genetics , Base Sequence , Humans , Molecular Sequence Data
15.
Cancer Res ; 52(13): 3615-21, 1992 Jul 01.
Article in English | MEDLINE | ID: mdl-1617633

ABSTRACT

Several heterocyclic amines, found in cooked food, are powerful mutagens in the Ames Salmonella mutagenicity test system. One of these, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) is one of the most mutagenic chemicals tested in this assay. In primary cultures of chick and rat hepatocytes, MeIQ, by itself, induced cytochrome P450 from the IA subfamily but was a weak inducer compared to 3-methylcholanthrene. However, in both chick and rat hepatocytes in culture, MeIQ decreased the amount of 3-methylcholanthrene-induced ethoxyresorufin deethylase activity, which is catalyzed by cytochrome P450 IA. The protein moiety of cytochrome P450 IA was decreased at MeIQ concentrations of 2.5 micrograms/ml or greater in chick hepatocytes and 25 micrograms/ml in rat hepatocytes. In hepatic microsomes from methylcholanthrene-treated chicks and rats, MeIQ was a competitive inhibitor of both ethoxyresorufin deethylase activity, a reaction catalyzed mainly by rodent cytochrome P450 IA1, and uroporphyrinogen oxidation, a reaction catalyzed by rodent P450 IA2. In cultured chick hepatocytes, MeIQ also decreased cytochrome P450-mediated oxidation of uroporphyrinogen by intact cells. The ability of MeIQ to inhibit as well as to induce cytochrome P450s of the IA subfamily may be important in assessing the mutagenic and carcinogenic effects of MeIQ in mammals.


Subject(s)
Cytochrome P-450 Enzyme System/analysis , Liver/drug effects , Mutagens , Quinolines/toxicity , Animals , Cells, Cultured , Chick Embryo , Cytochrome P-450 CYP1A1 , Liver/enzymology , Male , Oxidoreductases/analysis , Rats , Rats, Inbred F344 , Uroporphyrinogens/metabolism
16.
Am J Pathol ; 138(2): 333-40, 1991 Feb.
Article in English | MEDLINE | ID: mdl-1992760

ABSTRACT

Nodules of acinar cells with increased proliferative potential develop in the pancreas of carcinogen-treated rats and in untreated aged rats. Large nodules are classed as adenomas. Phenotypic and genotypic characteristics of nodule cells were compared with normal pancreas and transplantable acinar cell carcinomas by several methods. Nuclei of acinar cells from normal pancreas, adenomas, and three carcinomas in situ had normal diploid DNA content as determined by flow cytometry. One of two primary carcinomas had a hypodiploid DNA content. Two of three transplantable carcinomas were aneuploid with a DNA content in the tetraploid range. Explants from nodules and adenomas failed to grow in soft agar, whereas several carcinomas were positive in this assay. A primary carcinoma was serially transplanted, but transplantation of nodules or adenomas failed. Transfection of DNA from carcinomas in situ yielded a higher frequency of NIH 3T3 transformants than DNA from adenomas. DNAs from the transformants did not contain ras sequences. These studies indicate that cells from nodules and adenomas have low growth potential and lack critical phenotypic and genotypic characteristics of transformed malignant cells that were present in some primary and transplanted carcinomas.


Subject(s)
Adenoma/pathology , Carcinoma in Situ/pathology , Carcinoma/pathology , Pancreas/pathology , Pancreatic Neoplasms/pathology , Precancerous Conditions/pathology , Adenoma/metabolism , Animals , Carcinoma/metabolism , Carcinoma in Situ/metabolism , DNA/genetics , DNA/metabolism , Flow Cytometry , Male , Neoplasm Transplantation , Pancreas/metabolism , Pancreatic Neoplasms/metabolism , Ploidies , Rats , Rats, Inbred F344 , Rats, Inbred Lew
17.
Mol Carcinog ; 3(3): 165-70, 1990.
Article in English | MEDLINE | ID: mdl-2196902

ABSTRACT

The objective of this study was to determine whether activation of c-Ki-ras occurs in carcinogen-induced rat pancreatic tumors. DNAs from 27 samples, which included adenomas, carcinomas in situ, and adenocarcinomas arising in azaserine-treated rats and corn oil-gavaged rats along with a nafenopin-induced rat pancreatic adenocarcinoma were examined for mutation of c-Ki-ras at codons 12, 13, and 61 by using the polymerase chain reaction. Our results indicate that activation of c-Ki-ras is not a common event during pancreatic carcinogenesis in the rat.


Subject(s)
Adenocarcinoma/genetics , Adenoma/genetics , Gene Expression Regulation , Genes, ras , Pancreatic Neoplasms/genetics , Animals , Male , Mutation , Polymerase Chain Reaction , Rats , Rats, Inbred F344 , Rats, Inbred Lew
18.
Carcinogenesis ; 8(8): 1033-7, 1987 Aug.
Article in English | MEDLINE | ID: mdl-3496989

ABSTRACT

Using the technique of alkaline elution analysis, the ability of 11 known or suspected pancreatic carcinogens to damage the DNA of pancreatic acinar cells when administered to rats and hamsters was examined. The two species respond differently to several agents. In selected instances, DNA damage was also assessed in cultured pancreatic acinar cells exposed in vitro to the agents. Comparisons of DNA damage produced in vivo with that produced in vitro gave useful information on the role of pancreatic metabolism in activating pancreatic carcinogens. Finally, information germane to the question of the cell of origin for pancreatic cancer was obtained.


Subject(s)
Carcinogens/pharmacology , DNA Damage , Pancreas/drug effects , Animals , Cells, Cultured , Cricetinae , Male , Mesocricetus , Pancreatic Neoplasms/chemically induced , Rats , Rats, Inbred Lew , Species Specificity
19.
Pancreas ; 2(5): 518-22, 1987.
Article in English | MEDLINE | ID: mdl-3499606

ABSTRACT

The mutagenicity of azaserine was determined in a pancreatic acinar cell-mediated mutagenesis assay using V79 cells as the responder cell line. The mutation frequency of V79 cells was increased in direct culture with azaserine as well as in coculture with rat and hamster pancreatic acinar cells. Although slightly higher mutation frequencies were seen with coculture, the mutation frequency induced by azaserine in coculture was not significantly enhanced over that observed in direct culture. Thus, azaserine cannot be used as a positive control to monitor the level of acinar cell metabolism in such cell-mediated mutagenesis assays. Statistical analysis suggested that hamster acinar cell cocultures were more effective at increasing the mutation frequency of azaserine as compared to rat acinar cell cocultures. Hamster acinar cell cocultures, but not rat acinar cell cocultures, increased the mutagenicity of azaserine in a dose-response fashion. These results suggest that azaserine may be a pancreatic carcinogen for the hamster as well as the rat.


Subject(s)
Azaserine/pharmacology , Mutagenicity Tests , Pancreas/cytology , Animals , Azaserine/administration & dosage , Cells, Cultured , Cricetinae , Cricetulus/genetics , DNA Damage , Dose-Response Relationship, Drug , Male , Mesocricetus/genetics , Pancreas/metabolism , Rats , Rats, Inbred Lew/genetics
20.
Laryngoscope ; 97(1): 105-7, 1987 Jan.
Article in English | MEDLINE | ID: mdl-3796168

ABSTRACT

Intramuscular myxoma of the head and neck is a rare lesion with only six cases documented in the literature. The tumor demonstrates a benign clinical course without a tendency to recur and is occasionally associated with fibrous dysplasia. It thus deserves to be considered in a separate class from other soft tissue myxomas. The seventh case of a head and neck intramuscular myxoma is presented and the clinical, pathological, and CT characteristics of this tumor are reviewed.


Subject(s)
Head and Neck Neoplasms , Muscles , Neck Muscles , Aged , Diagnosis, Differential , Female , Head and Neck Neoplasms/diagnostic imaging , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/ultrastructure , Humans , Neoplasm Recurrence, Local , Tomography, X-Ray Computed
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