Biomedical subjects

Alberto Gobbi

Publications and source records attributed to Alberto Gobbi.

25 records · Page 2Linked to original sources

PubMed2002

Patellar tendon anterior cruciate ligament reconstruction with conical press-fit femoral fixation: 5-year results in athletes population.

Bone-patellar tendon autograft is probably the most widely used graft for ACL reconstruction. Several methods for graft fixation have been described. To avoid intra-articular hardware we adopt biological fixation with a femoral conical press-fit fixation. A prospective study was performed on 40 consecutive active athletes who underwent ACL reconstruction with this technique by the same surgeon between November 1994 and September 1995 (mean follow-up 46 months, range 36-62). Results were evaluated by an independent examiner using radiography, computed tomography, subjective and objective evaluation, and isokinetic and functional strength tests. Assessment using the IKDC knee scoring revealed 85% of the patients with a normal or nearly normal knee joint; Tegner's score was 7.5 preoperatively and 6.0 postoperatively, with 60% of the athletes returning to the preinjury sport and level. No patients had instability, with 90% having less than 3 mm side-to-side difference on computerized analysis. The isokinetic test showed mild quadriceps deficit at 3 and 6 months, with no deficit at final follow-up; four patients complained of anterior knee pain and had a positive kneeling test. We found no graft dislocation. All cases showed radiological evidence of graft integration at 3 months time. Long-term results support this technique asx a simple, cost-effective, and reliable alternative for patellar tendon fixation in ACL reconstruction.

Adult↗

PubMed2002

In vitro and in vivo hematopoietic potential of human stem cells residing in muscle tissue.

OBJECTIVE: We studied the in vitro and in vivo hematopoietic potential of human stem cells residing in muscle tissue collected from adults with head and neck cancer. MATERIALS AND METHODS: Adherent muscle cells were cultured in F12 medium with 10% fetal bovine serum and transplanted into immunodeficient mice. RESULTS: On day 12 we obtained a median of 500,000 adherent cells per gram muscle sample. Thy-1, endoglin, HER2/neu, and P1H12 were expressed in the majority of cells. CD34, VEGFR2, c-kit, VCAM-1, and CXCR4 were expressed in 0.5-1.5%, 1-5%, 1-15%, 9-15%, and 30% of cells, respectively. Immunodeficient mice transplanted with fresh muscle cells or less than 500,000 cultured cells showed little or no human engraftment. In mice transplanted with more than 500,000 cultured cells, up to 14% human CD45(+) hematopoietic cells (including myeloid and lymphoid subsets) were detected by flow cytometry. Engraftment was confirmed by polymerase chain reaction, Southern blotting, and DNA sequencing. Liver, muscle, and spleen evaluated for human DNA were positive in the majority of mice showing hematopoietic engraftment in the bone marrow. In vivo hematopoietic engraftment potential was maintained in cultured CD45(-) muscle cells transduced with the green fluorescence protein gene. CONCLUSIONS: Human stem cells residing in muscle tissue can generate multilineage hematopoiesis in immunodeficient mice. Surprisingly, this hematopoietic potential increased in cultured versus fresh cells from muscle tissue.

Adult↗

PubMed2002

Mdm4 (Mdmx) regulates p53-induced growth arrest and neuronal cell death during early embryonic mouse development.

We report here the characterization of a mutant mouse line with a specific gene trap event in the Mdm4 locus. Absence of Mdm4 expression results in embryonic lethality (10.5 days postcoitum [dpc]), which was rescued by transferring the Mdm4 mutation into a Trp53-null background. Mutant embryos were characterized by overall growth deficiency, anemia, improper neural tube closure, and dilation of lateral ventricles. In situ analysis demonstrated increased levels of p21(CIP1/Waf1) and lower levels of Cyclin E and proliferating cell nuclear antigen expression. Consistent with lack of 5-bromo-2'-deoxyuridine incorporation, these data suggest a block of mutant embryo cells in the G(1) phase of the cell cycle. Accordingly, Mdm4-deficient mouse embryonic fibroblasts manifested a greatly reduced proliferative capacity in culture. Moreover, extensive p53-dependent cell death was specifically detected in the developing central nervous system of the Mdm4 mutant embryos. These findings unambiguously assign a critical role for Mdm4 as a negative regulator of p53 and suggest that Mdm4 could contribute to neoplasias retaining wild-type Trp53. Finally, we provide evidence indicating that Mdm4 plays no role on cell proliferation or cell cycle control that is distinct from its ability to modulate p53 function.

Abnormalities, Multiple↗

PubMedDate not supplied

Patellar tendon versus quadrupled bone-semitendinosus anterior cruciate ligament reconstruction: a prospective clinical investigation in athletes.

PURPOSE: Patellar tendon and hamstrings are both used in anterior cruciate ligament (ACL) reconstruction, and comparisons have been reported with different results. The purpose of this clinical study was to compare the results of ACL reconstruction in athletes with 2 different graft types, both using bone-to-bone healing: bone-patellar tendon-bone graft and a quadrupled bone-semitendinosus graft. TYPE OF STUDY: Outcomes study. METHODS: From 1994 to 1997, 2 groups of 40 athletes who underwent ACL replacement with patellar tendon and quadrupled bone-semitendinosus grafts were prospectively evaluated. Preinjury activity level, age, and gender were comparable in both groups. All patients were operated on by the same surgeon within 5 months from injury and underwent group-specific rehabilitation programs. An independent examiner performed the final evaluations at 36 months. Review included clinical examination, radiographs, computed analysis, isokinetic and functional strength tests, and subjective and objective evaluation with standard knee scores. Additional procedures were recorded. Statistical analysis was performed with both parametric and nonparametric tests. RESULTS: Average surgical time was longer with the semitendinosus graft, and postoperative pain was higher in the patellar tendon group. Standard knee evaluation scores and subjective assessment revealed no significant differences. Isokinetic testing of flexion-extension and internal-external rotation showed lower quadriceps strength and a mild deficit of external rotation in the patellar tendon group and slightly lower flexor strength in the semitendinosus group at 12 months. Computerized laxity analysis showed no difference between the 2 groups with 90% of patients having less than 3 mm side-to-side difference, with a gender difference in the semitendinosus group. Kneeling pain was higher in patellar tendon group. CONCLUSIONS: The bone-patellar tendon-bone and quadrupled bone-semitendinosus autograft provide excellent grafts for ACL reconstruction. Both techniques are comparable regarding final stability, but in patients with extensor mechanism problems or those who engage in sports with a high incidence of patellar tendonitis, the semitendinosus graft should be considered.

Adult↗

PubMedDate not supplied

DISE: directed sphere exclusion.

The Sphere Exclusion algorithm is a well-known algorithm used to select diverse subsets from chemical-compound libraries or collections. It can be applied with any given distance measure between two structures. It is popular because of the intuitive geometrical interpretation of the method and its good performance on large data sets. This paper describes Directed Sphere Exclusion (DISE), a modification of the Sphere Exclusion algorithm, which retains all positive properties of the Sphere Exclusion algorithm but generates a more even distribution of the selected compounds in the chemical space. In addition, the computational requirement is significantly reduced, thus it can be applied to very large data sets.

Algorithms↗

PubMedDate not supplied

Process-driven information management system at a biotech company: concept and implementation.

While established pharmaceutical companies have chemical information systems in place to manage their compounds and the associated data, new startup companies need to implement these systems from scratch. Decisions made early in the design phase usually have long lasting effects on the expandability, maintenance effort, and costs associated with the information management system. Careful analysis of work and data flows, both inter- and intradepartmental, and identification of existing dependencies between activities are important. This knowledge is required to implement an information management system, which enables the research community to work efficiently by avoiding redundant registration and processing of data and by timely provision of the data whenever needed. This paper first presents the workflows existing at Anadys, then ARISE, the research information management system developed in-house at Anadys. ARISE was designed to support the preclinical drug discovery process and covers compound registration, analytical quality control, inventory management, high-throughput screening, lower throughput screening, and data reporting.

Journal Article↗

PubMedDate not supplied

A searching and reporting system for relational databases using a graph-based metadata representation.

Relational databases are the current standard for storing and retrieving data in the pharmaceutical and biotech industries. However, retrieving data from a relational database requires specialized knowledge of the database schema and of the SQL query language. At Anadys, we have developed an easy-to-use system for searching and reporting data in a relational database to support our drug discovery project teams. This system is fast and flexible and allows users to access all data without having to write SQL queries. This paper presents the hierarchical, graph-based metadata representation and SQL-construction methods that, together, are the basis of this system's capabilities.

Computer Simulation↗