Multidisciplinary lifestyle intervention in the obese: its impact on patients' perception of the disease, food and physical exercise.

BACKGROUND AND AIMS: To be successful, lifestyle intervention in obesity must take into account patients' views. The aim of the present study, conducted using a narrative-autobiographical approach, was to report on the perception of disease, food and physical exercise in a group of 80 obese patients during a structured multidisciplinary lifestyle intervention. METHODS AND RESULTS: Patients underwent lifestyle intervention, of three months' duration, structured in the following steps: 1) an initial medical examination; 2) an interview by a psychologist; 3) an assessment by a dietician, 4) a physical examination by a specialist in sports medicine; 5) an individualized program consisting of 24 sessions (two per week) of structured indoor exercise 6) eight sessions of group therapeutic education; 7) Nordic walking activity combined with walking excursions during weekends. All the narrative autobiographic texts obtained during the lifestyle intervention were submitted for content analysis; data were analysed according to the ''grounded theory'' method. According to patients' descriptions at the end of the intervention, lifestyle intervention resulted in enhanced self-efficacy and a reduction in their dependency on food and people; their fear of change was also diminished because, by undergoing intervention, they had experienced change. CONCLUSION: The findings made in the present qualitative analysis suggest that whenever multidisciplinary lifestyle intervention is planned for patients with obesity, it is of the utmost importance to tailor the approach while taking the following key aspects into account: motivation, barriers and/or facilitators in lifestyle change, patients' perceptions of obesity and relationship with food, diet and exercise.

An innovative model for changing the lifestyles of persons with obesity and/or Type 2 diabetes mellitus.

AIM: To describe the multidisciplinary lifestyle intervention model used in an experimental CURIAMO (Centro Universitario Ricerca Interdipartimentale Attività Motoria) project designed to validate the short- and long-term efficacy of the model in obesity and Type 2 diabetes. RESEARCH DESIGN AND METHODS: Over a 3-yr period, about 1000 adults (70% diabetes-free and overweight or obese; 30% with Type 2 diabetes and overweight or obese). INCLUSION CRITERIA: Age range 18-80 yr, body mass index >27 kg/m2 with or without Type 2 diabetes mellitus; participants will be divided into three age groups (18-45, 45-65, 65-80 yr). The study duration will be from 5 to 6 yr: 1 yr of intervention followed by a mean follow-up period of 4 yr. In the first years, after a 4- month intensive lifestyle intervention, subjects will follow a maintenance programme. The intervention, which includes seven steps, involves the following experts: endocrinologists, sport medicine doctors or cardiologists, psychologists, dietitians, educators, nurses, exercise physiologists, and promoters of outdoor activities. RESULTS: The main endpoint of the study is to measure the efficacy of the lifestyle improvement intervention, defined as a loss of at least 7% of body weight combined with an increase of at least 10 MET/h-1·week-1 of energy expenditure by physical activity, after 1 yr and during the follow-up. A cost/utility analysis of the model will be made in participants with diabetes. CONCLUSIONS: We expect that the CURIAMO model will be highly effective, and that the aim of the intervention will be achieved in more than 70% of cases.

Usefulness of a comprehensive neurophysiological assessment for early diagnosis and prognosis of traumatic brachial plexus injuries.

PURPOSE: To illustrate how a thorough neurophysiological evaluation allows early diagnosis and prognosis of traumatic brachial plexus injuries. METHODS: As examples, we report on the case of two patients with acute traumatic brachial plexus injuries for whom a comprehensive neurophysiological evaluation allowed early diagnosis and prognosis. RESULTS: Neurophysiological findings were consistent with complete proximal (root) lesion in one patient and a severe neuroapraxic block between Erb point and axilla in the other one. CONCLUSIONS: The two reported acute cases of traumatic brachial plexus injuries demonstrated the high diagnostic and prognostic value of the neurophysiological tests when fully utilized.

Replacing two conserved tyrosines of the EphB2 receptor with glutamic acid prevents binding of SH2 domains without abrogating kinase activity and biological responses.

Eph receptor tyrosine kinases play key roles in pattern formation during embryonic development, but little is known about the mechanisms by which they elicit specific biological responses in cells. Here, we investigate the role of tyrosines 605 and 611 in the juxtamembrane region of EphB2, because they are conserved Eph receptor autophosphorylation sites and demonstrated binding sites for the SH2 domains of multiple signaling proteins. Mutation of tyrosines 605 and 611 to phenylalanine impaired EphB2 kinase activity, complicating analysis of their function as SH2 domain binding sites and their contribution to EphB2-mediated signaling. In contrast, mutation to the negatively charged glutamic acid disrupted SH2 domain binding without reducing EphB2 kinase activity. By using a panel of EphB2 mutants, we found that kinase activity is required for the changes in cell-matrix and cell - cell adhesion, cytoskeletal organization, and activation of mitogen-activated protein (MAP) kinases elicited by EphB2 in transiently transfected cells. Instead, the two juxtamembrane SH2 domain binding sites were dispensable for these effects. These results suggest that phosphorylation of tyrosines 605 and 611 is critical for EphB2-mediated cellular responses because it regulates EphB2 kinase activity.

A novel signaling intermediate, SHEP1, directly couples Eph receptors to R-Ras and Rap1A.

The Eph family of receptor tyrosine kinases has been implicated in many developmental patterning processes, including cell segregation, cell migration, and axon guidance. The cellular components involved in the signaling pathways of the Eph receptors, however, are incompletely characterized. Using a yeast two-hybrid screen, we have identified a novel signaling intermediate, SHEP1 (SH2 domain-containing Eph receptor-binding protein 1), which is expressed in the embryonic and adult brain. SHEP1 contains an Src homology 2 domain that binds to a conserved tyrosine-phosphorylated motif in the juxtamembrane region of the EphB2 receptor and may itself be a target of EphB2 kinase activity, since it becomes heavily tyrosine-phosphorylated in cells expressing activated EphB2. SHEP1 also contains a domain similar to Ras guanine nucleotide exchange factor domains and binds to the GTPases R-Ras and Rap1A, but not Ha-Ras or RalA. Thus, SHEP1 directly links activated, tyrosine-phosphorylated Eph receptors to small Ras superfamily GTPases.

Elevated cyclins and cyclin-dependent kinase activity in the rhabdomyosarcoma cell line RD.

An important early event in the differentiation of skeletal muscle cells is exit from the cell cycle, after which full expression of the muscle phenotype occurs. Rhabdomyosarcoma (RMS), a tumor of skeletal muscle origin, expresses a number of muscle-specific proteins, including MyoD; however, these cells fail to arrest or differentiate when cultured in differentiation medium (DM). To determine the basis for the failure of RMS cells to differentiate or arrest, we studied the molecular response of the embryonal RMS cell line, RD, to culture in DM. Under these conditions, the retinoblastoma protein (RB) was primarily in the hyperphosphorylated state. This is in contrast to myoblasts cultured in DM, in which the hypophosphorylated form of RB is exclusively present. Measurements of the expression and activities of cyclin-dependent kinases (cdks) cdk2 and cdk4 indicated that RD cells maintained higher levels than do myoblasts, and the activity and abundance of these proteins did not significantly decrease upon culture in DM in RD cells, as they did in myoblasts. Similarly, elevated expression of cyclins D1, E, and A was observed in RD cells. Interestingly, cdk inhibitors are expressed in RD cells, with p16ink4 expression markedly elevated relative to myoblasts. Ectopic expression of p21cip1, p16ink4, or p27kip1 caused a growth arrest of RD cells but not detectable expression of a myogenic marker. Furthermore, a constitutively active RB protein could also inhibit the growth of RD cells without inducing myogenic differentiation. Taken together, these data suggest that the elevated levels of cdk2 and/or cdk4 observed in RD cells contribute to the inability of RD cells to growth arrest when cultured in DM but that these activities alone are not responsible for the failure of RD cells to differentiate.

Paclitaxel plus epirubicin in advanced breast cancer.

This phase I-II study aimed to determine the maximum tolerated dose (MTD) of paclitaxel (Taxol), infused over 3 hours, when combined with a fixed dose (90 mg/m2) of epirubicin. Other aims were to investigate the combination's plasma pharmacokinetics, toxicity, and activity in 50 patients with previously untreated metastatic breast cancer, as well as its ability to mobilize peripheral blood stem cells (PBSCs). The initial dose of paclitaxel, 135 mg/m2, was increased by 20 mg/m2 in subsequent cohorts of six patients until dose-limiting toxicity (DLT) occurred. The DLT of the combination was febrile neutropenia in two of eight patients who received paclitaxel at 225 mg/m2. The concentration of epirubicinol, the major metabolite of epirubicin, decreased from 47.3 +/- 9.4 ng/mL at 175 mg/m2 of paclitaxel to 37.9 +/- 7.5 ng/mL at the 225-mg/m2 dose. The most relevant toxicity was grade 4 neutropenia (61% of all the courses). Cardiac toxicity included three patients (6%) developing congestive heart failure responsive to therapy. Among 49 evaluable patients, 41 responses (84%) were observed (95% confidence interval [CI], 70% to 92%) and 9 (19%) of these were complete. In 21 patients, we evaluated the mobilization of PBSCs after this regimen plus a colony-stimulating factor. The median number of CD34+ cells was 61.7/microL (range, 6.8 to 201/microL), and a median of 6.3 x 10(6)/kg of CD34+ cells have been harvested with a single leukapheresis.

Purification of brain microtubule-associated protein MAP1A.

Brain microtubule-associated protein MAP1A has been purified until homogeneity by using a novel procedure involving copolymerization with microtubules, treatment with poly-L-aspartic acid and FPLC. The purified protein retains its capacity to facilitate microtubule assembly.

Negative growth control by a novel low M(r) phosphotyrosine protein phosphatase in normal and transformed cells.

Having determined the complete amino acid sequence of a cytosolic phosphatase purified from bovine liver, we studied the role of this enzyme (referred to as 'PTPase') in the control of cell proliferation. We used NIH/3T3 fibroblasts, both normal and transformed by the oncogenes v-erbB, v-src, and v-raf: a synthetic gene coding for PTPase was transfected into, and overexpressed in, normal and transformed NIH/3T3 cells with resulting inhibition of cell growth. Inhibition of proliferation correlated with the level of foreign PTPase; growth in soft agar was also inhibited in transformants overexpressing the enzyme. However, PTPase overexpression did not inhibit the rapid turnover of inositol lipids stimulated by platelet-derived growth factor. We conclude that this novel PTPase is active on cell type-specific signalling substrates that control normal and transformed fibroblast proliferation.

Differential role of four cysteines on the activity of a low M(r) phosphotyrosine protein phosphatase.

In this paper we describe the construction of five mutants of a bovine liver low M(r) phosphotyrosine protein phosphatase (PTPase) expressed as a fusion protein with the maltose binding protein in E. coli. Almost no changes in the kinetic parameters were observed in the fusion protein with respect to the native PTPase. Using oligonucleotide-directed mutagenesis Cys-17, Cys-62 and Cys-145 were converted to Ser while Cys-12 was converted to both Ser and Ala. The kinetic properties of the mutants, using p-nitrophenyl phosphate as substrate, were compared with those of the normal protein fused with the maltose binding protein of E. coli; both of the Cys-12 mutants showed a complete loss of enzymatic activity while the specific activity of the Cys-17 mutant was greatly decreased (200-fold). The Cys-62 mutant showed a 2.5-fold decrease in specific activity, while the Cys-145 mutant remained almost unchanged. These data confirm the involvement of Cys-12 and Cys-17 in the catalytic site and suggest that Cys-62 and Cys-145 mutations may destabilise the structure of the enzyme.

Overexpression of a synthetic phosphotyrosine protein phosphatase gene inhibits normal and transformed cell growth.

We studied the level of the cytosolic phosphotyrosine protein phosphatase (PTPase) (originally termed low-M(r) acid phosphatase) in normal NIH/3T3 and in v-erbB-transformed fibroblasts. The level of the enzyme, assayed by ELISA, was inversely related to cell proliferation, normally growing cells had less enzyme than their contact-inhibited counterparts and v-erbB transformants had less enzyme than normal NIH/3T3. In order to overexpress the enzyme and study its effects in normal and transformed cells, we transfected a synthetic gene coding for the PTPase in control NIH/3T3 and v-erbB transformants. The overexpressed enzyme was recognized by antibodies raised against the native enzyme and, in cells overexpressing the PTPase, we observed a marked dephosphorylation of tyrosyl residues of cellular proteins. Cell proliferation, in both normal and v-erbB transformants overexpressing the PTPase, was measured. We observed that PTPase overexpression was accompanied by significantly reduced thymidine incorporation in both cell types, either serum-starved or serum-stimulated. The ability of transformed v-erbB cells to grow in soft agar was also markedly decreased by overexpression of the enzyme. Taken together, our results indicate that overexpression of PTPase might interfere with mitogenic signalling pathways in both normal and transformed cells, and propose a role for PTPase in the control of cell proliferation.