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1.
Eur J Trauma Emerg Surg ; 44(2): 273-277, 2018 Apr.
Article in English | MEDLINE | ID: mdl-28756513

ABSTRACT

BACKGROUND: The treatment of perforated foregut ulcers by omental patching (OP) or primary closure has mostly replaced vagotomy and pyloroplasty/antrectomy (VPA). We sought to determine the natural history and recurrence rate of ulceration in patients treated by omental patching or primary closure. STUDY DESIGN: An 11-year retrospective study. RESULTS: From 2004 through 2015, 94 patients had perforated foregut ulcers, 53 gastric, and 41 duodenal. 77 (82%) were treated by OP alone (study group) and 17 (18%) were treated with VPA (comparison group). All OP patients were discharged on PPIs, but only 86% took the drugs for a median of 22 months (1-192, SD 40). Endoscopy in the OP group showed recurrent ulcers in nine (12% recurrence rate) and gastritis in three (4%) This group also had three later recurrent perforations. Another recurrent ulcer hemorrhaged causing death (3% late mortality). Two other patients required non-emergent re-do ulcer operations for recurrent disease/symptoms (surgical re-intervention rate 4%). Total length of follow-up was median 44 months (1-192, SD 40) and was complete in 82 (87%). 18 (23%) patients in the OP group developed recurrent abdominal pain attributed to ulcer disease during follow-up, compared to 2 (12%) in the VPA group (p = 0.15). No patient in the VPA group had an endoscopic recurrence or re-intervention. CONCLUSION: Omental patching does not correct the underlying disease process which causes foregut perforation, and has a 12% endoscopically proven recurrent ulceration rate and a 23% incidence of recurrent symptoms within 44 months. Patients tend to stop taking PPIs after 22 months at which time their risk increases.


Subject(s)
Omentum/transplantation , Peptic Ulcer Perforation/surgery , Disease-Free Survival , Female , Humans , Male , Michigan , Peptic Ulcer Perforation/mortality , Recurrence , Retrospective Studies , Treatment Outcome , Vagotomy, Proximal Gastric/methods
2.
Restor Neurol Neurosci ; 25(5-6): 513-26, 2007.
Article in English | MEDLINE | ID: mdl-18334769

ABSTRACT

PURPOSE: The infusion of 6-hydroxydopamine (6-OHDA) into the nigrostriatal pathway in rats is commonly used to produce an animal model of Parkinson's disease (PD). However, most studies use male adult animals only. The present study focused on possible gender differences in vulnerability to 6-OHDA during the early pubertal period when the effects exerted by gonadal steroid hormones are unpronounced. METHODS: Young Sprague-Dawley rats, 35 days of age, were given a low vs. a higher dose of 6-OHDA in the medial forebrain bundle (MFB). Control rats received equivalent saline infusions. At 14 days post-surgery the rats were evaluated for forelimb akinesia. RESULTS: For the higher dose of 6-OHDA the female rats were less impaired than males in making adjustment steps in response to a weight shift and in a vibrissae-evoked forelimb placing test. Tyrosine hydroxylase (TH) immunoreactivity was significantly higher for the female rats. CONCLUSION: Early gender differences in cell survival factors and/or other promoters of neuroplasticity may have contributed to the beneficial outcome in the females. For example, NGF was found to be higher in the female rats following administration of DA neurotoxin. It is unclear whether gonadal steroids are involved, and if so, whether female hormones are protective or whether male hormones are prodegenerative. Determining the mechanisms for the improved outcome in the young female rats may lead to potential treatment strategies in PD.


Subject(s)
Mental Disorders/chemically induced , Nerve Growth Factor/metabolism , Neurotoxicity Syndromes/etiology , Neurotoxins/toxicity , Oxidopamine/toxicity , Sex Characteristics , Analysis of Variance , Animals , Behavior, Animal , Disease Models, Animal , Dose-Response Relationship, Drug , Female , Male , Medial Forebrain Bundle/drug effects , Mental Disorders/pathology , Mental Disorders/physiopathology , Neurotoxicity Syndromes/pathology , Psychomotor Performance/drug effects , Rats , Rats, Sprague-Dawley , Tyrosine 3-Monooxygenase/metabolism , Vibrissae/drug effects , Vibrissae/innervation
3.
Aquat Toxicol ; 76(3-4): 230-45, 2006 Mar 10.
Article in English | MEDLINE | ID: mdl-16300839

ABSTRACT

The triazine herbicide atrazine has been suggested to be a potential disruptor of normal sexual development in male frogs. The goals of this study were to collect native ranid frogs from sites in agricultural and non-agricultural areas and determine whether hypothesised atrazine effects on the gonads could be observed at the gross morphological and histological levels. Juvenile and adult green frogs (Rana clamitans), bullfrogs (R. catesbeiana) and leopard frogs (R. pipiens) were collected in the summers of 2002 and 2003. Atrazine concentrations were below the limit of quantification at non-agricultural sites, and concentrations did not exceed 2 microg/L at most agricultural sites. One concentration greater than 200 microg atrazine/L was measured once at one site in 2002. Hermaphroditic individuals with both male and female gonad tissue in either one or both gonads, were found at a low incidence at both non-agricultural and agricultural sites, and in both adults and juveniles. Testicular oocytes (TO) were found in male frogs at most of the sites, with the greatest incidence occurring in juvenile leopard frogs. TO incidence was not significantly different between agricultural and non-agricultural sites with the exception of juveniles collected in 2003. Atrazine concentrations were not significantly correlated with the incidence of hermaphroditism, but maximum atrazine concentrations were correlated with TO incidence in juvenile frogs in 2003. However, given the lack of a consistent relationship between atrazine concentrations and TO incidence, it is more likely the TOs observed in this study result from natural processes in development rather than atrazine exposure.


Subject(s)
Agrochemicals/toxicity , Atrazine/toxicity , Disorders of Sex Development/veterinary , Herbicides/toxicity , Ranidae , Agrochemicals/analysis , Animals , Atrazine/analysis , Disorders of Sex Development/chemically induced , Disorders of Sex Development/epidemiology , Female , Gonads/anatomy & histology , Gonads/drug effects , Gonads/pathology , Gonads/ultrastructure , Herbicides/analysis , Incidence , Limb Deformities, Congenital/chemically induced , Limb Deformities, Congenital/epidemiology , Limb Deformities, Congenital/veterinary , Male , Michigan , Ranidae/anatomy & histology , Ranidae/physiology , Time Factors , Water/chemistry , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
4.
Aquat Toxicol ; 77(2): 153-66, 2006 May 01.
Article in English | MEDLINE | ID: mdl-16427146

ABSTRACT

The triazine herbicide atrazine has been hypothesized to disrupt sexual development in frogs by up-regulating aromatase activity, resulting in greater estradiol (E2) concentrations and causing feminization in males. The goal of this study was to collect native ranid frogs from atrazine-exposed ponds and determine whether relationships exist between measured atrazine concentrations and the gonadosomatic index (GSI), plasma concentrations of testosterone (T), E2 or 11-ketotestosterone (KT), or with aromatase activity. In the summer of 2002 and 2003, adult and juvenile green frogs (Rana clamitans), bullfrogs (R. catesbeiana) and Northern leopard frogs (R. pipiens) were collected from areas with extensive corn cultivation and areas where there was little agricultural activity in south-central Michigan. Atrazine concentrations were below the limit of quantification at non-agricultural sites. Atrazine concentrations did not exceed 2 microg/L at most agricultural sites, but a concentration of 250 microg atrazine/L was measured in one sample from one site in 2002. Plasma steroid concentrations varied among locations. Aromatase activity was measurable in less than 11% of testes in adult males, and in less than 4% of testes in juvenile males. Median aromatase activities in ovaries of adult females ranged from 3 to 245 pmol/h/mg protein, and maximum activities were 2.5-fold greater in juveniles than in adults. Atrazine concentrations were not significantly correlated with any of the parameters measured in this study. These results indicate that atrazine does not up-regulate aromatase in green frogs in the wild, and does not appear to affect plasma steroid hormone concentrations.


Subject(s)
Aromatase/metabolism , Atrazine/toxicity , Environmental Exposure , Herbicides/toxicity , Ranidae/physiology , Animals , Aromatase/drug effects , Estradiol/blood , Female , Fresh Water , Gonads/enzymology , Male , Michigan , Seasons , Sex Factors , Testosterone/analogs & derivatives , Testosterone/blood , Water Pollution, Chemical/adverse effects
5.
Eur J Trauma Emerg Surg ; 42(2): 219-23, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26038041

ABSTRACT

INTRODUCTION: Gunshot wounds through the liver are highly lethal and are prone to delayed morbidity due to late complications. METHODS: A retrospective study was performed to determine the incidence, morbidity, and need for late interventions in patients shot through the liver, and the role of post-injury CT in making those determinations. RESULTS: 83 patients were shot through the liver. Injury grades were: Grade V-12 (14 %), Grade IV-41 (49 %), Grade III-12 (14 %), Grade II-8 (10 %), Grade I-1 (1 %), and nine were ungraded. Ten (12 %) died in the ED, three (4 %) died in the OR, and two (2 %) died postoperatively. Of the 68 survivors, 52 (76 %) had follow-up CT scans performed a median of 7 days (95 % CI 2-13 days) after injury. Seventeen (33 %) had 25 complications related to the bullet tract: 12 (48 %) abscesses, 6 (24 %) infected hematomas, 3 (12 %) bilomas, 3 (12 %) unclassified fluid collections, and 1 (4 %) hepatic necrosis. Treatment included CT-guided drainage in 15 (60 %), ultrasound-guided drainage in 3 (12 %), surgical drainage and debridement in 2 (8 %), and observation in 5 (20 %). Overall morbidity rate including hepatic and non-hepatic complications was 74 % (50/68). Patients having their CT scan-determined intervention (for all complications) within 7 days of injury (n = 24), compared to those having their CT scan-determined intervention on day 8 or later (n = 28), had a significantly decreased rate of overall complications and morbidity (p = 0.03). This difference was due to early detection and intervention for abscesses, anastomotic breakdown, and missed injuries. Those having a CT scan within 7 days of injury also had a significantly reduced length of stay compared to those scanned on day 8 or later (median 14 days, 95 % CI 4-24 days versus 18 days, 95 % CI 6-30 days, p = 0.05). CONCLUSIONS: Gunshot wounds to the liver have a high morbidity and mortality rate. Survivors should have a follow-up CT scan performed within 7 days to allow detection and intervention for complications, as this dramatically decreases the overall morbidity rate and length of stay.


Subject(s)
Debridement/methods , Drainage/methods , Liver , Surgery, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Wounds, Gunshot , Adult , Female , Humans , Injury Severity Score , Length of Stay/statistics & numerical data , Liver/diagnostic imaging , Liver/injuries , Liver/surgery , Liver Abscess/diagnosis , Liver Abscess/etiology , Liver Abscess/surgery , Male , Retrospective Studies , Time-to-Treatment/statistics & numerical data , Treatment Outcome , Ultrasonography/methods , United States/epidemiology , Wounds, Gunshot/complications , Wounds, Gunshot/diagnosis , Wounds, Gunshot/mortality , Wounds, Gunshot/surgery
6.
Environ Pollut ; 135(1): 131-41, 2005 May.
Article in English | MEDLINE | ID: mdl-15701400

ABSTRACT

The objective of this study was to characterize concentrations of atrazine, terbuthylazine, and other pesticides in amphibian habitats in surface waters of a corn-production area of the western Highveld region (North-West Province) of South Africa. The study was conducted from November 2001 to June 2002, coinciding with the corn-production season. Pesticide residues were measured at regular intervals in surface water from eight ponds, three in a non-corn-growing area (NCGA) and five within the corn-growing area (CGA). Measured atrazine concentrations differed significantly among sites and between samples. In the five CGA sites, the maximum atrazine concentrations measured during the study ranged from 1.2 to 9.3 microg/L. Although no atrazine was recorded as being applied in the catchment of the three NCGA sites, maximum concentrations from 0.39 to 0.84 microg/L were measured during the study, possibly as a result of atmospheric transport. Maximum measured concentrations of terbuthylazine ranged from 1.22 to 2.1 microg/L in the NCGA sites and from 1.04 to 4.1 microg/L in the CGA sites. The source of terbuthylazine in the NCGA sites may have been in use other than in corn. The triazine degradation products, deisopropylatrazine (DIA) and deethylatrazine (DEA) and diaminochlorotriazine (DACT) were also found in water from both the CGA and NCGA sites. Concentrations of DIA were > or = 1 microg/L throughout the season, while DEA concentrations were mostly <0.5 microg/L before planting but increased after planting and application of herbicides to concentrations >2 microg/L in some locations. Concentrations of DACT were highly variable (LOD to 8 microg/L) both before and after planting and application, suggesting that they resulted from historical use of triazines in the area. Other herbicides such as simazine and acetochlor were only detected infrequently and pesticides such as S-metolachlor, cypermethrin, monocrotophos, and terbuphos, known to be used in the CGA, were not detected in any of the samples. Because of dilution by higher than normal rainfall in the study period, these concentrations may not be predictive of those in years of normal rainfall.


Subject(s)
Agriculture , Environmental Exposure , Seasons , Triazines , Environmental Monitoring/methods , Pesticides , South Africa , Water Pollutants, Chemical
7.
S Afr Med J ; 105(1): 17-20, 2015 Jan.
Article in English | MEDLINE | ID: mdl-26046155

ABSTRACT

Listerial brainstem encephalitis (LBE) is an uncommon form of listerial central nervous system infection that progresses rapidly and is invariably fatal unless detected and treated early. We report on six adult patients with LBE, of whom five were managed or co-managed by our unit during the period January - June 2012. All presented with a short prodromal illness followed by a combination of brainstem signs, including multiple cranial nerve palsies with emphasis on the lower cranial nerves, ataxia, motor and sensory long-tract signs, a depressed level of consciousness and apnoea. In two cases the diagnosis was delayed with adverse outcomes. LBE may be difficult to diagnose: clinicians may not be aware of this condition, the brainstem location may not be recognised readily, general markers of inflammation such as the erythrocyte sedimentation rate, C-reactive protein level or white cell count may be normal, and the cerebrospinal fluid is typically normal or there are only mild and nonspecific findings. Serological tests are unreliable, and diagnosis is achieved through blood cultures, magnetic resonance imaging and clinical recognition.


Subject(s)
Brain Stem/microbiology , Encephalitis/diagnosis , Listeriosis/diagnosis , Magnetic Resonance Imaging/methods , Adult , Brain Stem/physiopathology , C-Reactive Protein/metabolism , Disease Progression , Encephalitis/microbiology , Encephalitis/therapy , Female , Humans , Listeriosis/microbiology , Listeriosis/therapy , Male , Middle Aged , Prodromal Symptoms
8.
Neurosci Biobehav Rev ; 23(3): 451-5, 1999.
Article in English | MEDLINE | ID: mdl-9989431

ABSTRACT

It is commonly assumed that errors in animal memory paradigms such as delayed matching to sample, radial mazes, and food-cache recovery are due to failures in memory for information necessary to perform the task successfully. A body of research, reviewed here, suggests that this is not always the case: animals sometimes make errors despite apparently being able to remember the appropriate information. In this paper a case study of this phenomenon is described, along with a demonstration of a simple procedural modification that successfully reduced these non-memory errors, thereby producing a better measure of memory.


Subject(s)
Memory/physiology , Animals , Humans
9.
Endocrinology ; 124(2): 1007-16, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2536309

ABSTRACT

Immunohistochemical analysis revealed the colocalization of ACTH-related immunoreactive forms and alpha-MSH-related immunoreactive forms in corticotropic cells of the anterior pituitary of larval Ambystoma tigrinum. Subsequent analysis of acid extracts of anterior pituitaries obtained from larval, neotene, and postmetamorphic adults indicated that the molar ratio of ACTH(1-39) to alpha-MSH was, respectively, 2.5:1, 1:1.5, and 1:1.3. However, in sexually mature adults the molar ratio of ACTH(1-39) to alpha-MSH was 8:1. These results indicate that before and immediately after metamorphosis, both ACTH(1-39) and alpha-MSH are major end products of corticotropic cells in this species. As postmetamorphic animals reach sexual maturity, ACTH(1-39) is a major end product of corticotropic cells and only trace amounts of alpha-MSH are produced. Thus in A. tigrinum the proteolytic processing of ACTH in corticotropic cells is developmentally regulated. The alpha-MSH-related peptide produced by the corticotropic cells appears to be an ACTH(1-13)amide-like form.


Subject(s)
Adrenocorticotropic Hormone/analysis , Ambystoma/growth & development , Pituitary Gland, Anterior/growth & development , alpha-MSH/analysis , Aging , Animals , Brain/growth & development , Chromatography, Gel , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Immunoenzyme Techniques , Larva , Radioimmunoassay
10.
J Interferon Cytokine Res ; 19(10): 1145-52, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10547154

ABSTRACT

Biologically active interleukin-12 (IL-12), comprising a 40 kDa subunit (p40) covalently linked to a 35 kDa subunit (p35), is produced in response to a range of infectious stimuli. Here, we demonstrate that mice deficient in either IL-12 p40 (p40-/-) or IL-12 p35 (p35-/-) are susceptible to murine cytomegalovirus (MCMV) infection in terms of survival (Balb/c p35-/-) and viral clearance (Balb/c p35-/- and Balb/c p40-/-), and this susceptibility may be correlated to a deficiency in serum interferon-gamma (IFN-gamma) levels. These data support a role for endogenous IL-12 in controlling MCMV infection. The IL-12 p40 subunit is produced in excess of IL-12 p35, and to date the function of the excess endogenous p40 has been assumed to be one of IL-12 antagonism, as demonstrated by experiments with exogenous p40 both in vivo and in vitro. We show that Balb/c p35-/- alone are significantly compromised in survival of a sublethal infection and in clearance of virus from the spleen. These mice produce a very early IFN-gamma spike (8 h after infection) and an aberrant tumor necrosis factor-alpha (TNF-alpha) spike (day 2 after infection). MCMV infection has revealed an altered Balb/c p35-/- phenotype compared with Balb/c p40-/-, and this indicates that endogenous p40 may have an activity independent of and additional to IL-12 antagonism in vivo.


Subject(s)
Cytomegalovirus Infections/physiopathology , Immunity, Innate , Interleukin-12/physiology , Peptide Fragments/physiology , Animals , Cytomegalovirus Infections/immunology , Interleukin-12/chemistry , Metabolic Clearance Rate , Mice , Mice, Inbred BALB C , Survival Rate , Up-Regulation
11.
Neurology ; 45(7): 1405-8, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7617205

ABSTRACT

We report the clinical and electrophysiologic data on five subjects from two families with severe sensory and autonomic neuropathy who also exhibited peroneal muscular atrophy with the electrophysiologic features of an axonopathy, congenital cataracts, mental retardation, and skin lesions. One patient had hearing loss. Autosomal recessive inheritance was probable in both families.


Subject(s)
Cataract/etiology , Hereditary Sensory and Autonomic Neuropathies/genetics , Intellectual Disability/etiology , Skin Diseases/etiology , Adult , Cataract/genetics , Electromyography , Female , Humans , Intellectual Disability/genetics , Male , Middle Aged , Pedigree , Skin Diseases/genetics
12.
Proc Biol Sci ; 242(1304): 108-12, 1990 Nov 22.
Article in English | MEDLINE | ID: mdl-1706096

ABSTRACT

Expression in Xenopus oocytes of cloned nicotinic acetylcholine receptors (alpha, beta, gamma and delta subunits of BC3H1 receptor), produced more than one sort of functional receptor. This heterogeneity was detectable neither as heterogeneity in single channel conductance, nor as heterogeneity in the burst length. It was seen most obviously as differences from patch to patch in the maximum fraction of time for which the channels are held open at high acetylcholine concentrations, and it was also detectable as differences in the shut time distributions at low acetylcholine concentrations.


Subject(s)
Receptors, Nicotinic/metabolism , Acetylcholine/pharmacology , Animals , Cloning, Molecular , Electric Conductivity , Female , Gene Expression , Ion Channels/drug effects , Ion Channels/metabolism , Membrane Potentials , Mice , Oocytes/metabolism , Receptors, Nicotinic/drug effects , Receptors, Nicotinic/genetics , Xenopus laevis
13.
Antiviral Res ; 55(2): 307-17, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12103431

ABSTRACT

Oseltamivir carboxylate is a potent and specific inhibitor of influenza A and B neuraminidase (NA). Oseltamivir phosphate, the ethyl ester prodrug of oseltamivir carboxylate, is the first orally active NA inhibitor available for the prophylaxis and treatment of influenza A and B. It offers an improvement over amantadine and rimantadine which are active only against influenza A and rapidly generate resistant virus. The emergence of virus resistant to oseltamivir carboxylate in the treatment of naturally acquired influenza infection is low (about 1%). The types of NA mutation to arise are sub-type specific and largely predicted from in vitro drug selection studies. A substitution of the conserved histidine at position 274 for tyrosine in the NA active site has been selected via site directed mutagenesis, serial passage in culture under drug pressure in H1N1 and during the treatment of experimental H1N1 infection in man. Virus carrying H274Y NA enzyme selected in vivo has reduced sensitivity to oseltamivir carboxylate. The replicative ability in cell culture was reduced up to 3 logs, as was infectivity in animal models of influenza virus infection. Additionally, pathogenicity of the mutant virus is significantly compromised in ferret, compared to the corresponding wild type virus. Virus carrying a H274Y mutation is unlikely to be of clinical consequence in man.


Subject(s)
Acetamides/pharmacology , Antiviral Agents/pharmacology , Influenza A Virus, H1N1 Subtype , Influenza A virus/drug effects , Mutation/drug effects , Neuraminidase/genetics , Acetamides/chemistry , Acetamides/therapeutic use , Amino Acid Substitution , Animals , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , Body Weight , Cell Line , Disease Models, Animal , Drug Resistance, Viral/genetics , Ferrets , Fever/etiology , Humans , In Vitro Techniques , Inflammation/etiology , Influenza A virus/enzymology , Influenza A virus/genetics , Influenza A virus/pathogenicity , Influenza, Human/drug therapy , Influenza, Human/virology , Mice , Mice, Inbred BALB C , Mutagenesis, Site-Directed , Neuraminidase/antagonists & inhibitors , Neuraminidase/metabolism , Oseltamivir , Sequence Analysis, DNA , Virus Replication
14.
Arch Surg ; 135(12): 1469-74, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11115354

ABSTRACT

HYPOTHESIS: Amplification of the HER-2/neu oncogene in 25% of breast cancers is associated with a shortened disease-free survival. DESIGN: Retrospective analysis of a patient population referred to a tertiary care facility for HER-2/neu testing. The mean follow-up was 56 months. SETTING: Large, urban, tertiary care hospital. PATIENTS: From 1995 to 1999, a consecutive sample of 190 patients with breast cancer had tissue samples tested for overexpression of the cell surface oncoprotein by immunostaining (IM) or amplification of the HER-2/neu oncogene by fluorescence in situ hybridization or both. Forty-nine subjects were excluded because they had tissue samples tested at our institution but received their treatment elsewhere. All patients tested for HER-2/neu after diagnosis with breast cancer in 1999 (n = 47) were excluded from analysis because of short follow-up time. One patient was excluded who had in situ ductal carcinoma. The remaining 93 patients were analyzed. RESULTS: Of 93 patients, 40 (43%) had gene amplification. Overall, patients with oncogene amplification had a shorter median disease-free interval (22 months) compared with controls (40 months) (P =.003). Analysis by the Cox regression model showed that the HER-2/neu status remained significantly associated with time to relapse even after adjusting for age and tumor grade (P =.002; adjusted relative risk, 2.4; 95% confidence interval, 1.4-4.4). No association was found between gene amplification and tumor grade (P =.98), estrogen/progesterone receptor status (P = .29 and P = .43, respectively), or lymph node status (P = .98). Seventy-two patients (77%) eventually had disease recurrence, with 18 (25%) of these recurring locally. CONCLUSIONS: The HER-2/neu oncogene is an independent prognostic indicator of a subset of breast cancers that are at high risk of early recurrence, regardless of tumor grade, estrogen/progesterone receptor status, and lymph node status. Patients amplifying the HER-2/neu oncogene have a shorter disease-free survival than patients without the oncogene.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/pathology , Gene Amplification , Genes, erbB-2/genetics , Neoplasm Recurrence, Local/epidemiology , Neoplasm Recurrence, Local/genetics , Breast Neoplasms/therapy , Combined Modality Therapy , Follow-Up Studies , Humans , Neoplasm Metastasis , Prognosis , Retrospective Studies , Survival Rate
15.
Peptides ; 19(5): 931-7, 1998.
Article in English | MEDLINE | ID: mdl-9663460

ABSTRACT

[125I]beta-endorphin bound to high affinity (Kd = 0.25 nM) receptors in the caudal dorsomedial medulla of rats with a Bmax of 97 fmol/mg protein. The relative potency for displacement of [125I]beta-endorphin binding was: beta-endorphin(1-31) > beta-endorphin(1-27) > DAMGO > naloxone > N-acetyl-beta-endorphin(1-31) > U50488 > DPDPE. The Bmax for [3H]DAMGO binding was 81 fmol/mg protein, indicating that most [125I]beta-endorphin binding corresponds to mu-opioid receptors. [3H]DAMGO binding was not influenced by lesioning noradrenergic nerve terminals in the caudal dorsomedial medulla. Our findings indicate that beta-endorphin interacts primarily with mu-opioid receptors in the caudal dorsomedial medulla. These receptors are not affected by noradrenergic denervation.


Subject(s)
Medulla Oblongata/chemistry , Receptors, Opioid/analysis , Animals , Guanosine 5'-O-(3-Thiotriphosphate)/pharmacology , Iodine Radioisotopes , Logistic Models , Male , Rats , Rats, Sprague-Dawley
16.
Peptides ; 13(5): 913-7, 1992.
Article in English | MEDLINE | ID: mdl-1480515

ABSTRACT

Dopamine and gamma-aminobutyric acid (GABA) inhibit POMC peptide release from the pituitary intermediate lobe, via interaction with D2 or GABA-A/benzodiazepine receptors. Here, we examined the effects of an antianxiety triazolobenzodiazepine, adinazolam, on corticotropin-releasing factor (CRF)-stimulated POMC peptide secretion from the rat neurointermediate pituitary. Neurointermediate lobes (NILS) were incubated with CRF (10(-7) M), then adinazolam (10(-8) or (10(-9) M) was added, with CRF remaining in the medium. Aliquots were removed at 15-min intervals and frozen for radioimmunoassay of beta-endorphin. Adinazolam alone did not significantly affect secretion as compared to controls or CRF alone. Adinazolam incubated with CRF led to significant inhibition of beta-endorphin secretion, as compared to CRF alone. In addition, adinazolam was as effective as dopamine or the CRF antagonist, alpha-helical CRF, in preventing CRF-induced beta-endorphin release. Adinazolam appears to act directly on the pituitary to suppress hormone release induced by a stress-related hypothalamic peptide.


Subject(s)
Anti-Anxiety Agents , Benzodiazepines/pharmacology , Pituitary Gland/drug effects , beta-Endorphin/metabolism , Animals , Baclofen/pharmacology , Corticotropin-Releasing Hormone/antagonists & inhibitors , Corticotropin-Releasing Hormone/pharmacology , Dopamine/pharmacology , In Vitro Techniques , Male , Muscimol/pharmacology , Pituitary Gland/metabolism , Rats , Rats, Sprague-Dawley
17.
Regul Pept ; 47(2): 141-50, 1993 Sep 03.
Article in English | MEDLINE | ID: mdl-8234900

ABSTRACT

We used the met-enkephalin analog (D-Met2,Pro5)-enkephalinamide (DMPEA) to investigate enkephalinergic control of alpha-melanocyte-stimulating hormone (alpha-MSH) secretion. Systemic (s.c.) administration of DMPEA elevated plasma titers of alpha-MSH in a dose- and time-related manner. Pretreatment with the opiate antagonist naltrexone had no effect on basal plasma levels of alpha-MSH but blocked DMPEA-induced alpha-MSH release. Treatment with a dose of naltrexone sufficient to block DMPEA-induced secretion of alpha-MSH had no effect on stress-induced secretion of alpha-MSH. Although pretreatment with the dopamine receptor agonist apomorphine prevented DMPEA-induced alpha-MSH secretion, DMPEA had no effect on the synthetic activity of tuberohypophysial dopamine neurons as gauged by measuring the accumulation of 3,4-dihydroxyphenylalanine in the neurointermediate lobe (NIL) following administration of NSD-1015. In vitro treatment of isolated NILs with DMPEA resulted in a significant increase in alpha-MSH release. Naltrexone completely blocked the stimulatory effects of DMPEA on alpha-MSH release in vitro. Our results indicate that DMPEA stimulates alpha-MSH secretion by acting directly through opiate receptors at the level of the NIL.


Subject(s)
Enkephalin, Methionine/analogs & derivatives , alpha-MSH/metabolism , Animals , Dose-Response Relationship, Drug , Enkephalin, Methionine/antagonists & inhibitors , Enkephalin, Methionine/pharmacology , Male , Naltrexone/pharmacology , Pituitary Gland/drug effects , Pituitary Gland/metabolism , Rats , Rats, Sprague-Dawley , Time Factors , alpha-MSH/blood
18.
Neuropeptides ; 28(4): 219-25, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7596487

ABSTRACT

We investigated the potential influence of opioid and melanotropic peptides on endogenous norepinephrine (NE) release from the A2 noradrenergic cell group of rats using a static, fixed-volume incubation procedure. Norepinephrine release from slices of caudal dorsomedial medulla (CDMM) was evoked by high potassium concentrations (20 and 60 mM) in a Ca(2+)-dependent and dose-related manner. Treatment with the potent melanotropin agonist [Nle4,D-Phe7] alpha-MSH(NDP-MSH) had no effect on K(+)-induced NE release. In contrast, human beta-endorphin1-31 significantly reduced K(+)-stimulated NE release, but not in the presence of naloxone. The highly-selective mu-opioid agonist [D-Ala2, N-Me-Phe4, Gly-ol5]-enkephalin (DAMGO) also significantly reduced evoked NE release. The inhibitory effect of DAMGO was completely blocked by naloxone. Naloxone alone did not alter evoked NE release. The inhibitory effect of DAMGO was not enhanced by reducing the stimulatory concentration of K+. None of the peptides tested influenced basal NE release. These data indicate that melanotropin receptors do not regulate NE release in CDMM. In contrast, the opioid peptides DAMGO and beta-endorphin inhibit K(+)-stimulated release of endogenous NE. These data suggest a role for mu-opioid receptors in controlling NE release from A2 noradrenergic neurons.


Subject(s)
Medulla Oblongata/cytology , Norepinephrine/metabolism , Opioid Peptides/pharmacology , Animals , Calcium/pharmacology , Enkephalin, Ala(2)-MePhe(4)-Gly(5)- , Enkephalins/pharmacology , Male , Melanocyte-Stimulating Hormones/agonists , Naloxone/pharmacology , Norepinephrine/antagonists & inhibitors , Potassium/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, Opioid, mu/agonists , alpha-MSH/analogs & derivatives , alpha-MSH/pharmacology , beta-Endorphin/pharmacology
19.
Neuropeptides ; 34(1): 69-75, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10688972

ABSTRACT

We investigated the ability of selective opioid agonists and antagonists to influence pro-opiomelanocortin peptide secretion from the rat neurointermediate lobe in vitro. The mu-opioid agonist DAMGO ([D-Ala(2), N-Me-Phe(4), Gly(5)-ol]enkephalin) significantly stimulated beta-endorphin and alpha-melanocyte-stimulating hormone release relative to controls early (30 min) in the incubation period. Similar effects on beta-endorphin secretion were observed with the selective mu-opioid agonist dermorphin. The delta-opioid receptor agonist DPDPE ([D-Pen(2,5)]enkephalin) weakly inhibited beta-endorphin secretion relative to controls while the kappa-opioid receptor agonist U50488 had no effect. The mu-opioid selective antagonist CTOP (D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH(2)) inhibited basal beta-endorphin secretion while kappa- and delta-opioid receptor antagonists had no effect. Our data support a role for local mu-opioid receptor control of intermediate lobe pro-opiomelanocortin peptide secretion. Peptide secretion from melanotropes appears to be tonically stimulated by activation of mu-opioid receptors in the absence of intact neuronal innervation to the intermediate lobe.


Subject(s)
Analgesics, Opioid/pharmacology , Pituitary Gland/physiology , Pro-Opiomelanocortin/metabolism , Receptors, Opioid, delta/physiology , Receptors, Opioid, mu/physiology , alpha-MSH/metabolism , beta-Endorphin/metabolism , 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology , Animals , Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacology , Enkephalin, D-Penicillamine (2,5)-/pharmacology , In Vitro Techniques , Male , Oligopeptides/pharmacology , Opioid Peptides , Pituitary Gland/drug effects , Rats , Rats, Sprague-Dawley , Somatostatin/analogs & derivatives , Somatostatin/pharmacology
20.
Neuropeptides ; 19(3): 213-21, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1896131

ABSTRACT

Neurointermediate lobes (NILS) of the pituitary glands of adult male Sprague-Dawley rats were incubated in media in the presence of corticotropin-releasing factor (CRF), a stimulator of proopiomelanocortin (POMC) peptide release. Alpha-helical CRF, a peptide known to inhibit CRF induced POMC peptide release from the anterior pituitary, was incubated with NILS for a period of 90 min, to study its potential ability to modulate peptide release from the intermediate lobe. The alpha-helical peptide reduced beta-endorphin release from NILS, as measured by radioimmunoassay (RIA), when added for the entire incubation, or when added 30 min after start of the incubation period, with CRF present. Alpha-helical CRF alone reduced beta-endorphin release, as compared to control or CRF-treated lobes. Ultrastructural examination of intermediate lobes fixed at the end of incubations revealed a reduction in the numbers of Golgi-associated dense granules, an indicator of new peptide synthesis, in intermediate lobe tissue treated with alpha-helical CRF alone, both peptides together, or with CRF followed by alpha-helical peptide. The in vitro studies demonstrate the effectiveness of the antagonist peptide on intermediate lobe peptide secretion, thereby extending its effects to both POMC-secreting areas of the pituitary gland.


Subject(s)
Corticotropin-Releasing Hormone/pharmacology , Peptide Fragments/pharmacology , Pituitary Gland/metabolism , Pro-Opiomelanocortin/metabolism , beta-Endorphin/metabolism , Animals , Corticotropin-Releasing Hormone/chemistry , Corticotropin-Releasing Hormone/metabolism , Culture Media , Cytoplasmic Granules/ultrastructure , Golgi Apparatus/ultrastructure , Male , Microscopy, Electron , Pituitary Gland/drug effects , Pituitary Gland/ultrastructure , Radioimmunoassay , Rats , Rats, Inbred Strains
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