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1.
Quintessence Int ; 54(1): 54-62, 2023 Jan 13.
Article in English | MEDLINE | ID: mdl-36268945

ABSTRACT

OBJECTIVES: When performing CBCT sialography (sialo-CBCT), space-occupying lesions may be identified incidentally. The objective was to describe their radiologic-clinical-histopathologic correlations. METHOD AND MATERIALS: The archive of sialo-CBCT scans was retrospectively searched for suspected space-occupying lesions. Based on the scan and clinical-histopathologic data, the cases were divided into "pathologic" vs "normal," "intra-parenchymal" vs "extra-parenchymal," and "benign" vs "malignant." Two precalibrated, blinded radiologists performed a survey of the radiographic features of each scan. Cohen kappa, chi-square, Kruskal-Wallis, and Mann-Whitney tests assessed inter-observer agreement and radiologic-clinical-histopathologic correlations. RESULTS: In total, 27 (1.5%) suspected space-occupying lesions were found in 1,758 reports. Full follow-up data were available for 15 cases: four were "malignant," six were "benign," and the remaining five were "normal." Kappa showed substantial inter-observer agreement (0.8 to 1.0). Constant swelling correlated with "pathologic" cases (P = .003). Lesion diameter was greater in "pathologic" than "normal" (P < .001) cases, with a cut-off of 12.6 mm. Clinical and radiographic features were similar in "benign" and "malignant" lesions. "Intra-parenchymal" and "extra-parenchymal" space-occupying lesions correlated with "no-fill-region" (P = .01) and "main-duct-displacement" (P = .002), respectively. CONCLUSIONS: Suspected space-occupying lesions in sialo-CBCT with a diameter greater than 12.6 mm are likely to be "pathologic." No radiographic features were able to differentiate between "malignant" and "benign" space-occupying lesions.


Subject(s)
Cone-Beam Computed Tomography , Salivary Glands , Sialography , Humans , Cone-Beam Computed Tomography/methods , Retrospective Studies , Salivary Glands/diagnostic imaging , Sialography/methods , Spiral Cone-Beam Computed Tomography
2.
Cancer Chemother Pharmacol ; 90(2): 109-114, 2022 08.
Article in English | MEDLINE | ID: mdl-35802145

ABSTRACT

PURPOSE: To examine the ex- vivo ability of explanted human tumors and normal tissue to activate liposomal mitomycin C lipidic prodrug (MLP) by releasing the active free drug form, mitomycin C (MMC). METHODS: We tested conversion of MLP to MMC in an ex vivo assay using explanted tissues obtained during routine surgery to remove primary tumors or metastases. Tumor and adjacent normal tissue were obtained from freshly explanted tumors and were immediately deep frozen at - 70 °C. On test day, the fragments were thawed, homogenized and incubated in the presence of a fixed amount of liposomal MLP at 37 °C for 1 h. We measured MLP and its rate of conversion to MMC by HPLC. Controls included plasma, malignant effusions, red blood cells, tumor cell lines, mouse liver, and buffer with dithiothreitol, a potent reducing agent. RESULTS: Most patients tested (16/20) were diagnosed with colo-rectal carcinoma. The average fraction of MLP cleaved per 100-mg tumor tissue (21.1%, SEM = 1.8) was greater than per 100-mg normal tissue (16.6%, SEM = 1.3). When the tumor and normal tissue samples were paired by patient, the difference was statistically significant (p = 0.022, paired t test). Biological fluids did not activate liposomal MLP, while normal liver tissue strongly does. Interestingly, the omental fatty tissue also greatly activated MLP. CONCLUSIONS: Tumor tissue homogenates activate MLP with greater efficiency than the surrounding normal tissues, but far less than liver and adipose tissue. These observations demonstrate the bioavailability of liposomal MLP in human tumors, and its pharmacologic potential in cancer therapy.


Subject(s)
Mitomycin , Prodrugs , Animals , Cell Line, Tumor , Humans , Lipids , Liposomes , Mice , Mitomycin/pharmacology , Prodrugs/pharmacology
4.
Am J Trop Med Hyg ; 105(1): 204-206, 2021 05 17.
Article in English | MEDLINE | ID: mdl-33999846

ABSTRACT

Capillaria hepatica (syn. Calodium hepaticum) is a parasitic nematode of rodents, rarely infecting humans. An asymptomatic Israeli adult male with extensive travel history was diagnosed with a liver mass on routine post-thymectomy follow-up. Imaging and computer tomography (CT) guided biopsy were inconclusive. Surgical excision revealed an eosinophilic granuloma with fragments of a nematode suspected to be C. hepatica. Molecular methods verified the diagnosis, and the patient was treated empirically. This is the first case of hepatic capillariasis described in Israel, and the first to be diagnosed using molecular methods.


Subject(s)
Asymptomatic Diseases/therapy , Enoplida Infections/diagnosis , Enoplida/isolation & purification , Granuloma/diagnostic imaging , Granuloma/diagnosis , Granuloma/surgery , Liver Diseases, Parasitic/diagnosis , Animals , Humans , Israel , Male , Middle Aged , Treatment Outcome
6.
Perit Dial Int ; 41(3): 284-291, 2021 05.
Article in English | MEDLINE | ID: mdl-32400280

ABSTRACT

OBJECTIVES: Nontuberculous mycobacteria (NTM) infections pose a diagnostic challenge in peritoneal dialysis (PD) patients. In this study, we sought to identify findings that are suggestive of NTM infection in PD adult patients. METHODS: All patients with NTM exit-site infection (ESI) with/without tunnel infection and peritonitis identified during the last decade in eight medical centers in Israel were included. Clinical, microbiological, and outcome data were collected and analyzed. RESULTS: Thirty patients were identified; 16 had ESI (53%) and 14 had peritonitis (47%). Median age was 65 years (interquartile range 52-76). Abdominal pain and cloudy PD fluid were reported in all patients with peritonitis, whereas exit-site discharge and granulation tissue were common in patients with ESI. Fourteen patients (47%) had negative cultures prior NTM diagnosis, and isolation of diphtheroids or Corynebacterium spp. was reported in 9 of 30 patients (30%). Antimicrobial treatment prior to diagnosis was documented in 13 of 30 patients (43%). Delayed diagnosis was frequent. Treatment regimens and duration of therapy varied widely. In 26 of 30 (87%) patients, catheter was removed and 19 of 30 patients (63%) required permanent transition to hemodialysis. Two patients with peritonitis (2 of 14, 14%) and seven with ESI (7 of 16, 44%) were eligible for continuation of PD. CONCLUSIONS: Culture negative peritonitis, isolation of diphtheroids or Corynebacterium spp., previous exposure to antibiotics, and/or a refractory infection should all prompt consideration of PD-related NTM infection and timely workup. Catheter removal is recommended aside prolonged antimicrobial therapy. In select patients with ESI, continuation of PD may be feasible.


Subject(s)
Mycobacterium Infections, Nontuberculous , Peritoneal Dialysis , Peritonitis , Adult , Aged , Anti-Bacterial Agents/therapeutic use , Humans , Mycobacterium Infections, Nontuberculous/diagnosis , Mycobacterium Infections, Nontuberculous/epidemiology , Mycobacterium Infections, Nontuberculous/etiology , Nontuberculous Mycobacteria , Peritoneal Dialysis/adverse effects , Peritonitis/diagnosis , Peritonitis/epidemiology , Peritonitis/etiology
8.
Case Rep Pediatr ; 2019: 7920591, 2019.
Article in English | MEDLINE | ID: mdl-31198614

ABSTRACT

Cystic lymphangioma is an uncommon benign tumor that occurs primarily in children in the cervical region. We report the first case of a pleural-based cystic lymphangioma in an infant. The patient was admitted for RUL pneumonia. Because of the persistence of the radiographic findings despite clinical improvement, a computed tomography (CT) and a magnetic resonance imaging (MRI) scan were performed. They showed a multiloculated cystic lesion in the superior posterior right hemithorax. A surgical procedure was performed with complete resection of the tumor. Histopathological examination showed a pleural-based intrathoracic multicystic lymphangioma. One year after the surgery, the patient feels well without any sign of recurrence.

9.
Harefuah ; 158(4): 233-236, 2019 Apr.
Article in Hebrew | MEDLINE | ID: mdl-31032554

ABSTRACT

INTRODUCTION: The clinicopathologic characterization of tumoral intra-epithelial neoplasms of the gallbladder is fairly limited compared to that of similar tumors of the pancreatobiliary system. Until recently, pre-malignant lesions of the gallbladder were mostly reported as adenomas, which were microscopic and therefore regarded as benign and clinically inconsequential, whereas papillary lesions have been largely regarded as a papillary subtype of gallbladder invasive adenocarcinoma. In an attempt to create a unified terminology for these tumors, the term Intracholecystic papillary-tubular neoplasm (ICPN) was proposed to include all exophytic intra-epithelial tumors of the gallbladder measuring ≥1 cm under one category. A few studies which have retrospectively analyzed tumors fulfilling this category found them to be remarkable analogous to the more well-characterized intra-epithelial tumors of the pancreato-biliary system such as IPMN of the pancreas and IPNB of the bile ducts and as such they also represent an 'adenoma-carcinoma' sequence in the gallbladder. Since then a number of case series have been published which attempted to characterize the clinical and pathological features of these tumors and their relationship with invasive carcinoma. In this paper we report three cases of ICPN which represent different stages of the 'adenoma-carcinoma' sequence.


Subject(s)
Adenocarcinoma , Adenoma , Gallbladder Neoplasms , Adenocarcinoma/pathology , Adenoma/pathology , Gallbladder Neoplasms/pathology , Humans , Neoplasm Invasiveness , Retrospective Studies
11.
Endocr Relat Cancer ; 25(6): 677-686, 2018 06.
Article in English | MEDLINE | ID: mdl-29636368

ABSTRACT

Patients with neuroendocrine neoplasms (NENs) often require systemic treatment, which is frequently limited by the emergence of drug resistance. mTOR inhibitors (mTORi), such as RAD001 (everolimus), have been shown to inhibit neoplasm progression. mTORi stimulates autophagy, a degradation pathway that might promote the survival of neoplasm cells that are exposed to anti-cancer therapy. Chloroquine (CQ), a well-known anti-malarial and anti-rheumatic drug, suppresses autophagy. Based on our previous results, we hypothesized that CQ may enhance the anti-tumorigenic effects of mTORi by inhibiting autophagy and we aimed to examine the anti-tumorigenic effect of CQ, alone or in combination with RAD001. We established a NEN subcutaneous xenograft mouse model and evaluated the effect of the drugs on tumor growth, mTOR pathway, autophagy and apoptosis. CQ alone and in combination with RAD001 significantly decreased neoplasm volume. Histopathological analysis revealed that the combination of CQ and RAD001 markedly inhibited mTOR activity and neoplasm cell growth, along with accumulation of autophagosomes and increased apoptosis. In conclusion, CQ enhances the anti-tumorigenic effect of RAD001 in vivo by inhibiting autophagy. Clinical trials addressing the effects of CQ therapy on neoplasm progression in patients with NENs, mainly in those treated with mTORi, are warranted.


Subject(s)
Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chloroquine/therapeutic use , Everolimus/therapeutic use , Immunosuppressive Agents/therapeutic use , Neuroendocrine Tumors/drug therapy , Animals , Autophagy/drug effects , Cell Line, Tumor , Humans , Mechanistic Target of Rapamycin Complex 1/metabolism , Mice, Nude , Neuroendocrine Tumors/metabolism , Neuroendocrine Tumors/pathology , Xenograft Model Antitumor Assays
12.
Br J Cancer ; 114(4): 469-76, 2016 Feb 16.
Article in English | MEDLINE | ID: mdl-26812573

ABSTRACT

BACKGROUND: Progastrin-releasing peptide (ProGRP) is a potential marker for small-cell lung cancer (SCLC) in serum; however, it may be more stable in plasma. We investigated a new plasma assay (ProGRPp) and its usefulness in diagnosing and monitoring SCLC. METHODS: The marker concentrations were determined on the ARCHITECT i system. RESULTS: The assay could distinguish SCLC from non-small-cell lung cancer (NSCLC: area under the curve 0.931, 95% CI 0.893-0.969; cross-validated accuracy 0.813; sensitivity 84.0%, specificity 96.3%; at 140 pg ml(-1) cutoff). The probability of SCLC when ProGRPp was >140 pg ml(-1) was 91.8%, after adjusting for age, gender, and renal dysfunction. The NSCLC patients with ProGRPp >140 pg ml(-1) were at high risk (odds ratio=37.0, P<0.001) for tumours with neuroendocrine features. False negatives in SCLC were associated with a lack of thyroid transcription factor-1 (P<0.001). A decrease of ProGRPp to <140 pg ml(-1) during chemotherapy was significantly associated with the image-based response (P<0.001), and independently affected progression-free survival (PFS, relative risk=2.51, P=0.04) and overall survival (OS, relative risk=4.38, P=0.003), after adjustment for imaging response, performance status, and stage. CONCLUSIONS: The ProGRPp assay is specific and sensitive for diagnosing SCLC. Changes in ProGRPp during chemotherapy are significantly associated with image-based response, PFS, and OS.


Subject(s)
Biomarkers, Tumor/blood , Lung Neoplasms/blood , Peptide Fragments/blood , Small Cell Lung Carcinoma/blood , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Case-Control Studies , Diagnosis, Differential , Female , Humans , Lung Neoplasms/diagnosis , Lung Neoplasms/drug therapy , Male , Middle Aged , Monitoring, Physiologic/methods , Recombinant Proteins , Small Cell Lung Carcinoma/diagnosis , Small Cell Lung Carcinoma/drug therapy
13.
BMC Res Notes ; 7: 695, 2014 Oct 07.
Article in English | MEDLINE | ID: mdl-25287119

ABSTRACT

BACKGROUND: Gastrointestinal stromal tumors of the alimentary tract may present with severe bleeding. Localization and treatment of obscure gastrointestinal bleeding is challenging in cases of negative bi-directional endoscopy. CASE PRESENTATION: A previously healthy 64-year-old Caucasian female presented with clinical signs of active gastrointestinal bleeding. Esophagogastroduodenoscopy was normal, and colonoscopy revealed passage of blood from the small bowel. Computerized tomography angiography demonstrated a hypervascular lesion with active extravasation located in the jejunum. Angiography of the superior mesenteric artery revealed a focal hypervascular mass in the jejunum, and super selective distal coil embolization of the feeding vessel was performed. When the patient was taken for laparoscopic exploration, a 2.5 cm tumor arising from the anti-mesenteric border of the proximal jejunum was identified and resected with primary anastomosis. Pathological results demonstrated a gastrointestinal stromal tumor with a low proliferation index of 1%. Small erosions in the adjacent mucosa confirmed the locus of bleeding. CONCLUSIONS: Computerized tomography is a useful tool for initial diagnosis of submucosal alimentary tumors in patients with obscure but clinically overt gastrointestinal bleeding. Selective angiography, following positive computerized tomography findings, is an important modality to allow both localization and hemostasis in actively bleeding small bowel tumors, but the procedure carries the risk of bowel necrosis. Complete surgical resection remains the mainstay for treatment of gastrointestinal stromal tumors.


Subject(s)
Gastrointestinal Hemorrhage/diagnostic imaging , Gastrointestinal Hemorrhage/surgery , Gastrointestinal Stromal Tumors/diagnostic imaging , Gastrointestinal Stromal Tumors/surgery , Jejunal Neoplasms/diagnostic imaging , Jejunal Neoplasms/surgery , Laparoscopy , Tomography, X-Ray Computed , Biopsy , Cell Proliferation , Colonoscopy , Embolization, Therapeutic , Female , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/pathology , Gastrointestinal Stromal Tumors/complications , Gastrointestinal Stromal Tumors/pathology , Humans , Intestinal Mucosa/diagnostic imaging , Intestinal Mucosa/surgery , Jejunal Neoplasms/complications , Jejunal Neoplasms/pathology , Middle Aged , Predictive Value of Tests , Treatment Outcome
15.
J Am Acad Dermatol ; 70(1): 80-8, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24172204

ABSTRACT

BACKGROUND: H syndrome is an autosomal recessive genodermatosis with multisystem involvement caused by mutations in SLC29A3. OBJECTIVE: We sought to investigate the clinical and molecular findings in 79 patients with this disorder. METHODS: A total of 79 patients were included, of which 13 are newly reported cases. Because of the phenotypic similarity and molecular overlap with H syndrome, we included 18 patients with allelic disorders. For 31 patients described by others, data were gathered from the medical literature. RESULTS: The most common clinical features (>45% of patients) were hyperpigmentation, phalangeal flexion contractures, hearing loss, and short stature. Insulin-dependent diabetes mellitus and lymphadenopathy mimicking Rosai-Dorfman disease were each found in approximately 20%. Additional systemic features were described in less than 15% of cases. Marked interfamilial and intrafamilial clinical variability exists. Twenty mutations have been identified in SLC29A3, with no genotype-phenotype correlation. LIMITATIONS: In the 31 patients described by others, data were collected from the medical literature. CONCLUSIONS: H syndrome is a multisystemic disease with clinical variability. Consequently, all SLC29A3-related diseases should be considered a single entity. Recognition of the pleomorphic nature of H syndrome is important for diagnosis of additional patients.


Subject(s)
Contracture/genetics , Hyperpigmentation/genetics , Hypertrichosis/genetics , Nucleoside Transport Proteins/genetics , Skin Diseases, Genetic/genetics , Adolescent , Adult , Alleles , Child , Child, Preschool , DNA Mutational Analysis , Diabetes Mellitus, Type 1/genetics , Female , Fingers , Hearing Loss, Sensorineural/genetics , Humans , Hyperpigmentation/pathology , Hypertrichosis/pathology , Infant , Lymphatic Diseases/genetics , Male , Middle Aged , Mutation , Skin Diseases, Genetic/pathology , Syndrome , Toes , Young Adult
17.
J Clin Invest ; 121(5): 1709-21, 2011 May.
Article in English | MEDLINE | ID: mdl-21490396

ABSTRACT

Ulcerative colitis (UC) is a chronic inflammatory bowel disease that is closely associated with colon cancer. Expression of the enzyme heparanase is clearly linked to colon carcinoma progression, but its role in UC is unknown. Here we demonstrate for what we believe to be the first time the importance of heparanase in sustaining the immune-epithelial crosstalk underlying colitis-associated tumorigenesis. Using histological specimens from UC patients and a mouse model of dextran sodium sulfate-induced colitis, we found that heparanase was constantly overexpressed and activated throughout the disease. We demonstrate, using heparanase-overexpressing transgenic mice, that heparanase overexpression markedly increased the incidence and severity of colitis-associated colonic tumors. We found that highly coordinated interactions between the epithelial compartment (contributing heparanase) and mucosal macrophages preserved chronic inflammatory conditions and created a tumor-promoting microenvironment characterized by enhanced NF-κB signaling and induction of STAT3. Our results indicate that heparanase generates a vicious cycle that powers colitis and the associated tumorigenesis: heparanase, acting synergistically with the intestinal flora, stimulates macrophage activation, while macrophages induce production (via TNF-α-dependent mechanisms) and activation (via secretion of cathepsin L) of heparanase contributed by the colon epithelium. Thus, disruption of the heparanase-driven chronic inflammatory circuit is highly relevant to the design of therapeutic interventions in colitis and the associated cancer.


Subject(s)
Colitis/metabolism , Gene Expression Regulation, Neoplastic , Glucuronidase/metabolism , Animals , Biopsy , Cell Line, Tumor , Enzyme Activation , Humans , Immunohistochemistry/methods , Inflammation , Macrophages/metabolism , Male , Mice , Mice, Inbred BALB C , Phenotype , Polysaccharides/chemistry , Recombinant Proteins/chemistry
18.
Clin Endocrinol (Oxf) ; 74(5): 593-8, 2011 May.
Article in English | MEDLINE | ID: mdl-21470282

ABSTRACT

OBJECTIVE: Glucagonoma is a pancreatic neuroendocrine tumour that arises from alpha cells in the pancreas and is often accompanied by a characteristic clinical syndrome. DESIGN: In this report, we present the cumulative experience and clinical characteristics of six patients diagnosed with glucagonoma and the glucagonoma syndrome and treated at our centre during the past 25 years. RESULTS: Although the course of the disease was variable, some features were similar. The median age at diagnosis was 53·5 years; the median time from onset of symptoms to diagnosis was 39 months. Presenting symptoms were as follows: weight loss 5/6 (83%), necrotizing migratory erythema (NME) 5/6 (83%), diabetes mellitus 4/6 (66%) and diarrhoea, weakness and thrombosis 2/6 (33%). Plasma glucagon was elevated in all patients upon diagnosis (range 200-10,000 pm; N < 50). Skin biopsy was diagnostic only in 1/6 specimens obtained, even after revision. Metastatic disease developed in all patients; 4/6 initially presented with hepatic metastasis. All patient symptoms responded to somatostatin analogue therapy. In 4/6, the NME responded to amino acid solutions. Other modes of therapy were as follows: surgery in 3/6 patients, peptide receptor radioligand therapy with (90) Y-DOTATOC (PRRT) in 3/6 patients (two responses) and chemotherapy in three patients (two responded). Four out of six patients died of the disease, and median survival time was 6·25 years (range 2-11) from diagnosis and 8 years (range 8-16) from initial symptoms. Five-year survival was 66%. CONCLUSION: Our data indicate that somatostatin analogues and an aggressive surgical approach offer symptom relief and tumour control. Among other available treatment modalities, PRRT seems to hold the most promise.


Subject(s)
Glucagonoma/diagnosis , Glucagonoma/therapy , Necrolytic Migratory Erythema , Pancreatic Neoplasms , Endocrine Gland Neoplasms/diagnosis , Endocrine Gland Neoplasms/therapy , Glucagonoma/diagnostic imaging , Glucagonoma/drug therapy , Glucagonoma/surgery , Humans , Middle Aged , Necrolytic Migratory Erythema/diagnosis , Necrolytic Migratory Erythema/therapy , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/therapy , Radionuclide Imaging , Retrospective Studies , Somatostatin/therapeutic use , Survival Rate , Syndrome , Treatment Outcome
19.
Endocrine ; 39(2): 160-6, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21069578

ABSTRACT

Metastases appear in approximately 10% of patients with pheochromocytoma. There is no predictive marker of malignancy. The aim is to describe clinical course of patients with malignant pheochromocytoma and to identify predictive features of malignancy. The method involves retrospective analysis of patients files diagnosed with malignant pheochromocytoma at our institution between January 1, 1980 and December 31, 2008. We identified 16 patients with malignant pheochromocytoma. There were more men than women (10/6). Mean age of patients at time of diagnosis was 37.75-year-old. Time of occurrence of metastases ranged from 0 to 22 years after first diagnosis of pheochromocytoma. The mean size of the primary tumor was 12.1 cm. High levels of chromogranin A at the time of diagnosis were associated with the presence of metastases. The pheochromocytoma of the adrenal gland scoring scale (PASS) histological evaluation in adrenal primary tumors was above four in all cases but one. All patients had initial surgery, followed in most cases by palliative therapy: chemotherapy (streptozocin, cyclophosphamide-vincristine-dacarbazine, thalidomide, imatinib, everolimus) or (131)I-MIBG; only the latter had replicable encouraging response evaluation criteria in solid tumor response rates. We observed a 10-year survival rate of 50% after initial diagnosis of pheochromocytoma, and 25% after diagnosis of metastasis. Metastasis can occur very late after the initial diagnosis of pheochromocytoma. High chromogranin A levels may be associated with the presence of metastases and poor prognosis. Histological adrenal PASS higher than 4 appears to be suggestive of malignancy. The best therapeutic approach remains to be established.


Subject(s)
Adrenal Gland Neoplasms/physiopathology , Pheochromocytoma/physiopathology , Pheochromocytoma/secondary , Adolescent , Adrenal Gland Neoplasms/therapy , Adult , Female , Humans , Male , Middle Aged , Palliative Care , Paraganglioma, Extra-Adrenal/physiopathology , Paraganglioma, Extra-Adrenal/therapy , Pheochromocytoma/therapy , Retrospective Studies , Survival Analysis , Young Adult
20.
J Vasc Res ; 47(6): 507-18, 2010.
Article in English | MEDLINE | ID: mdl-20431299

ABSTRACT

Haptides are a family of 19-21-mer cell-binding and permeating peptides homologous to sequences in the C termini on both fibrinogen ß- and γ-chain (Cß and preCγ, respectively). The effect of the Haptides on the cardiovascular system was studied by different assays, including the activity of isolated perfused rat heart and blood vessels in the organ bath. Haptides (50-80 µg/ml) decreased the hemodynamic functions of perfused rat hearts by up to 60% (p < 0.05) in a dose-dependent manner. Whole fibrinogen or a control nonrelated peptide (Cα) did not show such an effect. The NO donor, sodium nitroprusside, reversed the inhibitory effects of Haptides. L-NAME, an endothelial nitric oxide synthase (eNOS) inhibitor, did not further augment the effect of the Haptides. Perfused (FITC)Haptides were attached to the coronary endothelium. In myocardial homogenates and HUVEC, Haptides significantly decreased eNOS activity, but had no effect on the contraction of isolated cultured adult cardiomyocytes. Haptides also significantly enhanced the contraction of rings of rat aorta and human mammary artery vessels ex vivo only when the endothelium was intact. Haptides seem to affect the coronary endothelium, but not the cardiomyocytes, by inhibiting eNOS activity, causing vasoconstriction, temporary ischemia and impaired myocardial function that seem to be related to the amino acid composition of the Haptides.


Subject(s)
Coronary Vessels/drug effects , Endothelial Cells/drug effects , Enzyme Inhibitors/pharmacology , Fibrinogen/pharmacology , Mammary Arteries/drug effects , Nitric Oxide Synthase Type III/antagonists & inhibitors , Peptides/pharmacology , Animals , Cells, Cultured , Coronary Vessels/enzymology , Dose-Response Relationship, Drug , Endothelial Cells/enzymology , Fibrinogen/chemistry , Hemodynamics/drug effects , Humans , In Vitro Techniques , Male , Mammary Arteries/enzymology , Myocytes, Cardiac/drug effects , Nitric Oxide/metabolism , Nitric Oxide Donors/pharmacology , Nitric Oxide Synthase Type III/metabolism , Perfusion , Protein Structure, Tertiary , Rats , Rats, Sprague-Dawley , Time Factors , Vasoconstriction/drug effects , Ventricular Function, Left/drug effects
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