Graphitic molecules with partial "zig/zag" periphery.

A new synthetic protocol that affords novel hexa-peri-hexabenzocoronene (HBC) derivatives with partial "zig/zag" periphery and dramatically different electronic properties has been developed, which represents an important step toward understanding structure-property relationships of graphitic materials. The scope of this methodology was broadened by application to a much larger polycyclic aromatic hydrocarbon (PAH) with a more extended "zig/zag" character.

Origin, nature, and fate of the fluorescent state of the green fluorescent protein chromophore at the CASPT2//CASSCF resolution.

Ab initio CASPT2//CASSCF relaxation path computations are employed to determine the intrinsic (e.g., in vacuo) mechanism underlying the rise and decay of the luminescence of the anionic form of the green fluorescent protein (GFP) fluorophore.

Photochemical and electronic properties of conjugated bis(azo) compounds: an experimental and computational study.

We have investigated the photophysical, photochemical and electrochemical properties of two bis(azo) derivatives, (E,E)-m-1 and (E,E)-p-1. The two compounds, which can be viewed as being composed of a pair of azobenzene units sharing one of their phenyl rings, differ only for the relative position of the two azo groups on the central phenyl ring-meta and para for m-1 and p-1, respectively. The UV-visible absorption spectra and photoisomerisation properties are noticeably different for the two structural isomers; (E,E)-m-1 behaves similarly to (E)-azobenzene, while (E,E)-p-1 exhibits a substantial red shift in the absorption bands and a decreased photoreactivity.

HER-2/neu amplification by fluorescence in situ hybridization in cytologic samples from distant metastatic sites of breast carcinoma.

Background: Amplification of the HER-2/neu oncogene has been proposed as a target for antibody-based therapies and as a predictor of chemoresponsiveness in advanced breast carcinoma. Few studies have concentrated on HER-2/neu gene evaluation by fluorescence in situ hybridization (FISH) on distant metastatic sites and none have been performed on cytologic samples. The current study evaluated HER-2/neu amplification by FISH on cytologic samples obtained from distant metastatic lesions of breast carcinoma to update HER-2/neu characterization through a safe and easier procedure than biopsy.

Neuroblastic tumors associated with opsoclonus-myoclonus syndrome: histological, immunohistochemical and molecular features of 15 Italian cases.

The aim of this study was to investigate the histological, immunohistochemical and molecular features of a series of children with neuroblastic tumors (NTs) and opsoclonus-myoclonus syndrome (OMS). Of 1187 children (age 0-15 years) with previously untreated NTs registered between 1979 and 1995, 15 (1.3%) had OMS at presentation.

Electronic states and transitions in C60 and C70 fullerenes.

A review of the most relevant aspects of fullerene electronic structure and spectroscopy is presented. Experimental data and their interpretation based on computational results are discussed both for fullerene C60 and C70, with particular attention to the properties of the isolated molecule. Concerning singlet state spectroscopy, it is shown that because of its high symmetry, only dipole-forbidden electronic states are found in the low excitation energy region of C60.

Expression of HER2/neu is uncommon in human neuroblastic tumors and is unrelated to tumor progression.

Neuroblastic tumors (NT) are the most frequently occurring extracranial solid tumors during childhood. The overall 5-year survival is approximately 20% for patients with metastatic disease. Novel treatments are therefore intensively sought and tumor-targeted immuno- and chemotherapy appear promising.

Reactive hyperemia and tissue-type plasminogen activator release in hypertensive men.

A relationship may exist between endothelial-mediated vasodilation and tissue-type plasminogen activator (t-PA) release. However, the existing evidence is mainly based upon exogenous agonist administration, and needs testing under more physiological conditions. We evaluated the link between t-PA, the key fibrinolytic factor in man, and forearm reactive hyperemia, a model of endogenous endothelial-mediated vasodilation, in 13 uncomplicated hypertensive subjects and six elderly hypertensive patients with atherosclerotic peripheral vascular disease and hypercholesterolemia (i.

A 12-month clinical investigation with a 24-day regimen containing 15 microg ethinylestradiol plus 60 microg gestodene with respect to hemostasis and cycle control.

The effects of a 24-day regimen containing 15 microg ethinyl estradiol (EE) plus 60 microg gestodene on cycle control and on hemostasis, were evaluated in 58 healthy women (age 19-47 years). All women received the pill for 12 months. Withdrawal bleeding at every cycle during the tablet-free interval was experienced by 84.

Bcl-2 expression in pancreas development and pancreatic cancer progression.

Apoptosis is important for both tissue development and differentiation; its deregulation may contribute to tumourigenesis. In order to clarify the role of Bcl-2, an apoptosis-inhibiting protein, in pancreatic morphogenesis and tumour progression, its immunohistochemical expression was evaluated in 12 samples of fetal pancreas, in 10 samples of adult pancreas with ductal hyperplastic lesions, in 120 cases of primary pancreatic ductal adenocarcinoma, and in 43 synchronous metastatic lymph nodes. To evaluate the role of apoptosis in pancreatic cancer, p53 expression was also studied in tumour samples.

Activation of coagulation in smoking and non-smoking women using a third-generation oral contraceptive containing desogestrel.

The concurret use of smoking and oral contraceptives affects the hemostatic balance, thereby inducing a thrombophilic state. In order to clarify the effects of this association on the hemostatic system, the possible changes in the markers of activation of coagulation (thrombin-antithrombin III complexes and prothrombin fragment F1+2) were evaluated in 35 women given a third-generation oral contraceptive for 6 months; 13 of these women (37.1%) were mild or moderate smokers.

Local insulin infusion stimulates expression of plasminogen activator inhibitor-1 and tissue-type plasminogen activator in normal subjects.

Purpose: Plasma levels of plasminogen activator inhibitor-1 are increased in obesity, hypertension, and diabetes. Their correlation with insulin levels supports the hypothesis that hypofibrinolysis may affect the development of atherosclerotic complications in patients with insulin resistance. To investigate the effect of insulin on fibrinolysis, we evaluated levels of plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) antigens during insulin infusion in the forearm vascular beds of 8 healthy subjects.

p53 overexpression in lymph node metastases predicts clinical outcome in ductal pancreatic cancer.

In this study, we evaluated the prognostic significance of both p53 overexpression and proliferating activity in 133 primary ductal pancreatic carcinomas and in their regional synchronous lymph node metastases by immunohistochemistry, by using DO7 and MIB1 monoclonal antibodies, respectively. Tumor samples and lymph nodes were obtained from formalin-fixed, paraffin-embedded archival material of patients operated on between 1976 and 1996. Patients had a well-documented clinical history and were given accurate follow-up.

Preoperative enzymo-histochemical diagnosis of dysganglionoses associated with anorectal malformations (ARM) with recto-vestibular and recto-perineal fistula.

The posterior sagittal anorectoplasty (PSARP) is widely recognized as the best technique available today for the surgical treatment of anorectal malformations (ARM). However, different retrospective studies on the functional results of PSARP in the treatment of ARM have shown different postoperative degrees of constipation. In particular, even in patients with normal sacrum, about 70% of operated ARM with vestibular fistula and about 50% with perineal fistula can be complicated by fecal constipation and pseudoincontinence.

Acetylcholine-mediated vasodilatation and tissue-type plasminogen activator release in normal and hypertensive men.

Muscarinic agents release tissue plasminogen activator (t-PA) in the forearm circulation of normal subjects, but no information exists about their effect in those hypertensive patients in whom the response to endothelial-mediated vasodilators is blunted. Acetylcholine, an endothelium-dependent vasodilator and a muscarinic agonist that releases t-PA from in-vitro systems, and sodium nitroprusside, an endothelium-independent vasodilator, were infused into the brachial artery at rates calculated to cause a similar degree of vasodilatation. The study was performed in five elderly, smoking hypertensive patients in whom the clustering of detrimental factors for endothelial function permitted prediction of defective endothelial-mediated vasorelaxation, and five young, normotensive, nonsmoking male volunteers.

GDNF deficit in Hirschsprung's disease.

Background/purpose: In 1996, the glial cell line-derived neurotrophic factor (GDNF) was identified as one of the ligands of the RET transmembrane receptor. In the same year, GDNF mutations were found in association with RET protooncogene mutations in Hirschsprung patients. Mutations in GDNF per se are thought neither necessary nor sufficient to cause Hirschsprung's disease (HD).

Relationship between breast cancer and thyroid disease: relevance of autoimmune thyroid disorders in breast malignancy.

The relationship between thyroid dysfunction and breast cancer (BC) is debated. To clarify this controversial issue, a prospective study on thyroid function in BC was performed. The prevalence of thyroid disease was examined in 102 consecutive BC patients with ductal infiltrating carcinoma after surgery and before starting any chemohormonal or x-ray therapy and in 100 age-matched control healthy women living in the same borderline iodine-sufficient geographic area.

Fibrin degradation in the synovial fluid of rheumatoid arthritis patients: a model for extravascular fibrinolysis.

The patterns of degradation and the influence of factor XIII polymerization on fibrin stability were examined in vitro following incubation with leukocyte elastase. In vivo experiments, various factor XIII-polymerized fibrin clots were implanted subcutaneously in mice to evaluate the stability of clots in the extravascular space. Both in vitro and in vivo lysis proceeded faster with nonpolymerized fibrin and was not influenced by the presence of cross-linked alpha 2-plasmin inhibitor.

Thrombin-antithrombin III complexes as an additional diagnostic aid in pulmonary embolism.

Plasma levels of selected coagulation and fibrinolytic parameters (activated partial thromboplastin time, prothrombin time, fibrinogen, antithrombin III, protein C, thrombin-anti-thrombin III complexes (TAT), plasminogen activator inhibitor-1 (PAI-1), plasminogen, alpha 2-plasmin inhibitor) were evaluated in 90 patients with clinical suspicion of pulmonary embolism (PE). Plasma levels of fibrinogen, PAI-1 and TAT were significantly higher in patients than in controls (p < 0.01): evaluation of TAT displayed a sensitivity of 96.

Late miocene tidal deposits in the amazonian foreland basin.

Late Miocene tidal sediments of Acre, Brazilian Amazonia, were deposited in an embayment or interior seaway located in the sub-Andean zone. This late Tertiary embayment system may once have connected the Caribbean with the South Atlantic. The tidal coasts of the embayment-seaway have provided an avenue for the earliest waif (over water) dispersal phases of the great American biotic interchange in the late Miocene.

Presence of endothelin-1 in the normal and pathological human thyroid.

An immunohistochemical study with two rabbit polyclonal antibodies I-AR76 and CA-08-351 against Endothelin-1 (ET-1) was performed in 133 human thyroid specimens: 5 normal thyroids, 30 multinodular goiters (15 toxic and 15 nontoxic), 20 Graves' diseases, 5 Hashimoto's thyroiditis, 26 adenomas (6 Hürthle cell, 16 toxic and 4 nontoxic), 30 classic papillary carcinomas, 3 minimally invasive follicular carcinomas, 1 widely invasive follicular carcinoma, 3 undifferentiated carcinomas and 10 medullary carcinoma. All normal thyroids, non toxic multinodular goiters and non toxic adenomas, 4 (66%) Hürthle cell adenomas, 3 (15%) Graves' diseases, 1 (33%) case of minimally invasive follicular carcinoma showed rare follicular cells with weak cytoplasmic immunoreactivity. Many immunoreactive follicular cells, with or without oxyphilic changes, were observed in all specimens of Hashimoto's disease, while the lymphocytic infiltrate was always negative.