Altered surface myoelectric signals in peripheral vascular disease: correlations with muscle fiber composition.

Conduction velocity (CV) and median frequency (MDF) during tetanic electrical stimulation of the tibialis anterior muscle were evaluated in patients with uncomplicated peripheral arterial occlusive disease. Results were analyzed with respect to biopsy determination of diameter and proportion of types 1 and 2 muscles fibers. Initial MDF and CV correlated positively with type 2, but not type 1 fiber diameter.

Chronic administration of suramin induces neurotoxicity in rats.

In the present study, the ability of suramin 18 mg/kg i.p. twice a week to induce chronic neurotoxicity in rats was investigated.

Internal hemipelvectomy in the treatment of recurrent carcinoma of the colon: report of a case.

Purpose: Although extended surgery has been established as an effective method for the treatment of advanced carcinoma of the colon, there are no reports in the literature of en bloc resection of the tumor together with the iliac bone. We report herein a 46-year-old woman with a second local recurrence after right colectomy, with the main objective of showing the possibility of indicating this type of surgery in selected cases.

Methods: In view of the lack of therapeutic options for the case and the absence of metastases, extended curative surgery for recurrent carcinoma of the colon was performed, with en bloc resection of the right iliac bone and of the crural nerve (Type I internal hemipelvectomy).

The multiple endocrine neoplasia type 2B point mutation switches the specificity of the Ret tyrosine kinase towards cellular substrates that are susceptible to interact with Crk and Nck.

The RET proto-oncogene encodes a Tyrosine Kinase Receptor (RTK) which plays an important function in the proliferation and/or differentiation of neuroectodermic cells. Germline mutation of a methionine to a threonine within the RET TK domain predisposes to the Multiple Endocrine Neoplasia type 2B (MEN 2B). It has been demonstrated that, unlike c-Ret, the MEN 2B mutated Ret displays constitutive TK activity, tyrosine autophosphorylation and transforms fibroblasts.

Differential SP220K expression in renal carcinoma and oncocytoma cells.

SP220K is a newly described serine proteinase which displays guanidinobenzoatase activity in its inactive form and gelatinolytic activity in its active form. SP220K expression was studied in 20 renal clear-cell carcinomas and in a series of renal oncocytomas, a rare benign tumor derived from the kidney tubule epithelium. We provide evidence that SP220K expression, as assessed by guanidinobenzoatase activity, gelatin zymography and Western blot immunodetection, was increased markedly in cancer basolateral membranes compared to kidney cortex controls, whereas no signal was detectable in basolateral membranes from the 5 renal oncocytomas studied.

Endopeptidase 24.11 (CD10/NEP) is required for phorbol ester-induced growth arrest in Jurkat T cells.

Jurkat T cells express a functional endopeptidase 24.11 that is involved in the regulation of T cell activation. We have analyzed the effect of ectopic CD10 expression in mutant Jurkat cell clones that fail to express CD10 and, unlike wild-type cells, are resistant to the growth-inhibitory effects of the protein kinase C activator, PMA.

Electrically-elicited surface mechanomyogram in myotonic dystrophy.

Unlabelled: The surface oscillation of the muscle during electrical stimulation is detectable by an accelerometer as a surface mechanomyogram (MMG). The aim of this study was to evaluate whether MMG properties reflect the mechanical muscle changes induced by myotonic dystrophy (MyD). To this end, the tibialis anterior of seven MyD patients and seven age- and sex-matched controls (C) was supramaximally stimulated at 1 (single twitches), 5, 10, 15, 20 Hz for 3 s at the most proximal motor point.

Platelet monoamine oxidase molecular activity in demented patients.

Blood platelet monoamine oxidase activity, as well as other platelet enzyme activities, have been studied in several neuropsychiatric disorders in an attempt to identify biochemical markers of altered brain function. In this study, we determined both total and molecular monoamine oxidase activity in platelets derived from demented patients, which showed significantly greater enzyme activity than those of the controls. It therefore seems that the high degree of monoamine oxidase activity depends on the increased intrinsic activity of individual enzyme molecules.

CSF-1 stimulation induces the formation of a multiprotein complex including CSF-1 receptor, c-Cbl, PI 3-kinase, Crk-II and Grb2.

Recently c-Cbl has been reported to be phosphorylated upon CSF-1 stimulation. The product of the c-cbl proto-oncogene (c-Cbl) is a 120 kDa protein harboring several docking sites for Src homology 2 (SH2) domain containing proteins and proline-rich regions that have been shown to allow its constitutive association with the SH3 domains of Grb2. We demonstrate here that CSF-1 exposure of stable transfectant CHO cells expressing the CSF-1 receptor induced the sustained tyrosine phosphorylation of c-Cbl and its subsequent association with Crk-II and the p85 kDa subunit of the PI 3-kinase, while it constitutively associates with Grb2.

Cleavage site mutants of the subtype B insulin receptor are uncleaved and fully functional.

The insulin receptor (IR) is a membrane-bound glycoprotein composed of alpha and beta subunits derived from a common precursor. This processing is observed for both subtypes A and B of the IR and its physiological importance is poorly understood. In order to investigate the functional consequences of the absence of IR precursor cleavage, using site-directed mutagenesis of the hIRB cDNA, we have produced two mutants replacing the sequence Arg-Lys-Arg-Arg by either His-Lys-His-Arg or Arg-Lys-Arg-Ser.

Human monocytes express amphiregulin and heregulin growth factors upon activation.

In the last few years, three new heparin binding growth factors that interact with the Epidermal Growth Factor receptor (EGFR) and/or the related p185erbB-2 tyrosine kinase have been identified. Amphiregulin (AR) and Heparin-Binding EGF-like growth factor (HB-EGF) bind and activate the EGFR while Heregulin (HRG) acts through the p185erbB-2 and p180erbB-4 tyrosine kinases. Recently, activated macrophages were reported to secrete a p185erbB-2- and a heparin binding EGFR-stimulatory activities.

Interleukin 6 stimulates a tyrosine kinase activity potentially involved in mouse hybridoma cell growth.

In this report the authors describe the characterization of a cytosolic tyrosine kinase activity (IL-6PTK) stimulated by interleukin 6 (IL-6). IL-6PTK appears 6 h after IL-6 addition and is inhibited by tyrphostin but not genistein. It is active under its phosphorylated form although it is not immunoprecipitated by antiphosphotyrosine antibodies, suggesting that autophosphorylation occurs on residues other than tyrosine.

Mild clinical expression of myasthenia gravis associated with autoimmune thyroid diseases.

Myasthenia gravis (MG) may occur in association with autoimmune thyroid diseases (AITD). The aim of this study was to evaluate the features of MG associated with AITD compared to those of MG without AITD. A total of 129 MG patients (34 men and 95 women; age range, 11-81 yr) were subdivided into: group A, 56 MG patients with AITD [25 with autoimmune thyroiditis and 31 with Graves' disease (GD)]; group B, 21 MG patients with nonautoimmune thyroid diseases; and group C, 52 MG patients without thyroid disease.

CD10 (endopeptidase 24.11) is a thymic peptide-degrading enzyme possibly involved in the regulation of thymocyte functions.

Human immature thymocytes express significant levels of the CD10 (endopeptidase 24.11) cell surface antigen. We report here that IOB5, an anti-CD10 mAb, as well as the phorbol ester PMA down-regulate CD10 activity at the surface of human thymocytes.

Different effects of levodopa and apomorphine on blink reflex recovery cycle in essential blepharospasm.

With the aim of assessing dopaminergic responsiveness in essential blepharospasm, we investigated the effects of oral levodopa and subcutaneous apomorphine on blink reflex recovery cycle in 7 blepharospasm patients. We found that in blepharospasm the excitability of the blink reflex recovery cycle was increased compared with control subjects. The oral administration of levodopa/carbidopa (500/50 mg) did not significantly modify the blink reflex recovery cycle.

Potential use of iodine-123 metaiodobenzylguanidine radioaerosol as a marker of pulmonary neuroadrenergic function.

Iodine-123 metaiodobenzylguanidine (123I-MIBG) radioaerosol is of potential use in the investigation of the neuroadrenergic function of the lungs; however, before the method can be successfully employed the following issues need to be clarified: (1) Does the nebulization affect the radiochemical purity of 123I-MIBG? (2) Is the pulmonary distribution of inhaled 123I-MIBG homogeneous in normal subjects? (3) Does the pulmonary clearance of inhaled 123I-MIBG reflect the functional status of the neuroadrenergic system of the lungs? In this study we performed: (1) a chromatographic study of nebulized 123I-MIBG; (2) a quantitative evaluation of the lung distribution of 123I-MIBG radioaerosol in normal subjects as compared with that of technetium-99m diethylene triamine penta-acetic acid (99mTc-DTPA) and (3) an assessment of 123I-MIBG lung clearance both under control conditions and after pharmacologically induced beta-blockade, again compared with 99mTc-DTPA. For these purposes, eight normal subjects were divided randomly into an "MIBG group" and a "DTPA group" (four subjects each) and submitted to three scintigraphic studies each: a baseline study, and studies after the administration of a low (80 mg) and a high (160 mg) dose of propranolol. Radiochemical purity of nebulized 123I-MIBG ranged between 97.

Chordoma: retrospective analysis of 24 cases.

Introduction: Chordoma is a rare and slow-growing tumor, with local aggressiveness and preferential localization in the vertebral column.

Objective: The main objective of this study is to evaluate natural history and results of treatment of chordomas.

Methodology: This is a retrospective study from 1953 to 1993.

Prognostic factors in carcinoma of the penis: multivariate analysis of 145 patients treated with amputation and lymphadenectomy.

Purpose: The major issue in penile cancer is deciding who should or should not undergo lymph node dissection. Clinical and invasive methods are not reliable for staging. Clinical and pathological factors involved in lymph node metastases and prognosis were evaluated in 145 patients with penile carcinoma staged according to the 1978 TNM system, and treated with amputation and lymphadenectomy.

Tyrosine phosphorylation of I kappa B-alpha activates NF-kappa B without proteolytic degradation of I kappa B-alpha.

The transcription factor NF-kappa B regulates genes participating in immune and inflammatory responses. In T lymphocytes, NF-kappa B is sequestered in the cytosol by the inhibitor I kappa B-alpha and released after serine phosphorylation of I kappa B-alpha that regulates its ubiquitin-dependent degradation. We report an alternative mechanism of NF-kappa B activation.

Evidence of strategic effects in the modulation of orienting of attention.

Two models of visual orienting of attention are frequently described. Voluntary orienting is usually induced by central cues that direct subjects' attention to a given location in the visual space. Automatic orienting is provoked by presentation of peripheral cues.

Muscle modifications in Parkinson's disease: myoelectric manifestations.

The muscle changes occurring in Parkinson's disease (PD) may come about as a consequence of the modified pattern of motor unit activation and rigidity, which are characteristic of the disease. A tendency towards hypertrophy of type I fibers and, in some instances, atrophy of type II fibers has been observed. Fourteen patients affected by PD and 10 age-matched controls were studied in order to investigate these muscle changes.

Unreliability of modified inguinal lymphadenectomy for clinical staging of penile carcinoma.

Background: In 1988, Catalona proposed a modified bilateral inguinal lymphadenectomy for staging of lymph node metastasis from penile carcinoma. All three patients with penile carcinoma submitted to this procedure and without histologically confirmed metastases were free of disease within a mean follow-up time of 14.6 months.