TV watching modifies obesity risk linked to the 27Glu polymorphism of the ADRB2 gene in girls.

OBJECTIVE: A matched case-control study was conducted in a population of Spanish children and adolescents (5-18 years old), to assess the interaction between the Gln27Glu polymorphism of the ADRB2 and television (TV) watching on obesity risk. PATIENTS: Obese (n=165) and control subjects (n=165) matched by sex and age were recruited and classified according to Spanish reference data. Results. Using conditional logistic regression, we calculated the obesity risk linked to the polymorphism. A statistically significant association was found for 27Glu carrier allele girls (OR = 1.95; 95% CI = 1.02-3.70), but no association was apparent among boys. In the fully adjusted model, the odds ratio for obesity linked to the genotype Glu27Glu in the female population rose to 4.84 (95% CI = 1.37-17.10). Moreover, we found a significant negative interaction between hours of TV watching and the Gln27Glu polymorphism for obesity risk in girls. Surprisingly, among 27Glu carrier subjects, even girls with a low level of TV watching ( < 12.5 h/week) had a high obesity risk (OR = 4.60; 95% CI = 1.01-20.02), which was not very different to the odds ratio values for sedentary girls carrying the 27 Glu allele watching TV more than 12.5 h/week (OR = 6.05; 95% CI = 1.31-27.71). Conclusion. A higher risk of obesity was found for girls carrying the 27Glu allele of the ADRB2 gene even when they spent less than 12.5 h/week watching TV. In addition, our results suggest that the effect of sedentary lifestyle on obesity risk may depend on the genotype of the subject.     

Cell-cycle-specific genes differentially expressed in human leukemias.

Three cDNA clones isolated from Syrian hamster cells (p4F1, p2F1, and p2A9) contain sequences that are preferentially expressed in the G1 phase of the cell cycle. The expression of these sequences was investigated in human peripheral blood cells from normal individuals and from patients with leukemia. The expression of p4F1 and p2F1 is clearly dependent on the cell cycle in peripheral blood mononuclear cells stimulated to proliferate with phytohemagglutinin; the p2A9 sequences cannot be clearly detected in human lymphocytes but are expressed in a cell-cycle-dependent manner in human diploid fibroblasts (WI-38). These genes also show different levels of expression in lymphoid and myeloid leukemias. The highest level of expression for p2A9 is found in patients with chronic myelogenous leukemia, and the lowest in patients with chronic lymphocytic leukemia. For p2F1 and p4F1, the highest levels of expression are found in chronic and acute myelogenous leukemia. At least two other cell-cycle genes are not expressed at detectable levels in human leukemias. These findings suggest that the activation of cell-division-cycle genes might contribute, like cellular oncogenes, to the phenotype of human malignancies and that, perhaps, new oncogenes could be found by identifying and isolating genes whose expression is dependent on the cell cycle.     

Prospective evidence of the superiority of a sonography-based algorithm in the assessment of blunt abdominal injury.

BACKGROUND: Although the routine use of FAST (focused assessment with sonography for trauma) in the evaluation of trauma victims is increasing, to our knowledge, a prospective comparison of contemporary adult trauma victims managed with and without FAST has not been reported in North America. METHODS: Adult victims of blunt trauma for whom there was a suspicion of abdominal injury were managed with one of two diagnostic algorithms, FAST or no-FAST. The two algorithms were compared for diagnostic accuracy, cost, time, and delayed diagnoses. RESULTS: Among 706 patients (mean Injury Severity Score, 23), 460 were managed with FAST and 246 with no-FAST. The two groups were similar with respect to age, Injury Severity Score, prehospital time, and mortality (p = not significant). There were 3 of 460 (0.7%) delayed diagnoses in the FAST group and 4 of 246 (1.6%) in the no-FAST group (p = not significant). The diagnostic accuracy for the FAST and no-FAST algorithms was 99% and 98%, respectfully. The FAST and no-FAST algorithms led to similar rates of laparotomy, 13% and 14%, respectfully, but nonoperative management was more common in the no-FAST group (p < 0.01). The mean diagnostic cost for the FAST algorithm was $156, compared with $540 with the no-FAST algorithm (p < 0.0001) and the mean time required for diagnostic work-up was 53 minutes with the FAST algorithm, compared with 151 minutes with the no-FAST algorithm (p < 0.0001). CONCLUSION: This study has provided prospective evidence that a FAST-based algorithm for blunt abdominal injury was more rapid, less expensive, and as accurate as an algorithm that used computed tomography or diagnostic peritoneal lavage only. Trauma centers are encouraged to incorporate a FAST-based algorithm into their initial management of blunt trauma victims.     

Effect of the Total Facet Arthroplasty System after complete laminectomy-facetectomy on the biomechanics of implanted and adjacent segments

Background contextLumbar fusion is traditionally used to restore stability after wide surgical decompression for spinal stenosis. The Total Facet Arthroplasty System (TFAS) is a motion-restoring implant suggested as an alternative to rigid fixation after complete facetectomy.PurposeTo investigate the effect of TFAS on the kinematics of the implanted and adjacent lumbar segments.Study designBiomechanical in vitro study.MethodsNine human lumbar spines (L1 to sacrum) were tested in flexion-extension (+8 to ?6 Nm), lateral bending (±6 Nm), and axial rotation (±5 Nm). Flexion-extension was tested under 400 N follower preload. Specimens were tested intact, after complete L3 laminectomy with L3–L4 facetectomy, after L3–L4 pedicle screw fixation, and after L3–L4 TFAS implantation. Range of motion (ROM) was assessed in all tested directions. Neutral zone and stiffness in flexion and extension were calculated to assess quality of motion.ResultsComplete laminectomy-facetectomy increased L3–L4 ROM compared with intact in flexion-extension (8.7±2.0 degrees to 12.2±3.2 degrees, p<.05) lateral bending (9.0±2.5 degrees to 12.6±3.2 degrees, p=.09), and axial rotation (3.8±2.7 degrees to 7.8±4.5 degrees p<.05). Pedicle screw fixation decreased ROM compared with intact, resulting in 1.7±0.5 degrees flexion-extension (p<.05), 3.3±1.4 degrees lateral bending (p<.05), and 1.8±0.6 degrees axial rotation (p=.09). TFAS restored intact ROM (p>.05) resulting in 7.9±2.1 degrees flexion-extension, 10.1±3.0 degrees lateral bending, and 4.7±1.6 degrees axial rotation. Fusion significantly increased the normalized ROM at all remaining lumbar segments, whereas TFAS implantation resulted in near-normal distribution of normalized ROM at the implanted and remaining lumbar segments. Flexion and extension stiffness in the high-flexibility zone decreased after facetectomy (p<.05) and increased after simulated fusion (p<.05). TFAS restored quality of motion parameters (load-displacement curves) to intact (p>.05). The quality of motion parameters for the whole lumbar spine mimicked L3–L4 segmental results.ConclusionsTFAS restored range and quality of motion at the operated segment to intact values and restored near-normal motion at the adjacent segments.     

Culture of human bone marrow-derived mesenchymal stem cells on of poly(l-lactic acid) scaffolds: potential application for the tissue engineering of cartilage

Purpose

Due to the attractive properties of poly(l-lactic acid) (PLLA) for tissue engineering, the aim was to determine the growth and differentiation capacity of mesenchymal stromal cells (MSCs) in PLLA scaffolds and their potential use in the treatment of cartilage diseases.

Methods

MSCs were cultured in PLLA films and thin porous membranes to study adherence and proliferation. Permeability and porosity were determined for the different scaffolds employed. The optimal conditions for cell seeding were first determined, as well as cell density and distribution inside the PLLA. Scaffolds were then maintained in expansion or chondrogenic differentiation media for 21 days. Apoptosis, proliferation and chondrogenic differentiation was assessed after 21 days in culture by immunohistochemistry. Mechanical characteristics of scaffolds were determined before and after cell seeding.

Results

MSCs uniformly adhered to PLLA films as well as to porous membranes. Proliferation was detected only in monolayers of pure PLLA, but was no longer detected after 10 days. Mechanical characterization of PLLA scaffolds showed differences in the apparent compression elastic modulus for the two sizes used. After determining high efficiencies of seeding, the production of extracellular matrix (ECM) was determined and contained aggrecan and collagens type I and X. ECM produced by the cells induced a twofold increase in the apparent elastic modulus of the composite.

Conclusions

Biocompatible PLLA scaffolds have been developed that can be efficiently loaded with MSCs. The scaffold supports chondrogenic differentiation and ECM deposition that improves the mechanics of the scaffold. Although this improvement does not met the expectations of a hyaline-like cartilage ECM, in part due to the lack of a mechanical stimulation, their potential use in the treatment of cartilage pathologies encourages to improve the mechanical component.     

Titanium elastic nailing in femoral diaphyseal fractures of children in 6-16 years of age

Background:

Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.

Materials and Methods:

Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.

Results:

All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.

Conclusion:

Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group.     

Chemokines and diabetic wound healing

Chemokines are critical for white blood cell recruitment to injured tissues and play an important role in normal wound healing processes. In contrast, impaired wound healing in diabetic patients is accompanied by decreased early inflammatory cell infiltration but persistence of neutrophils and macrophages in the chronic, nonhealing wounds. These changes in inflammatory cell recruitment occur in conjunction with alterations in chemokine and growth factor expression. In addition to leukocyte trafficking, many different cell types, including endothelial cells, fibroblasts, and keratinocytes, produce and respond to chemokines, and these interactions are altered in diabetic wounds. Thus, the chemokine system may have both direct and inflammatory-mediated effects on many different aspects of diabetic wound healing. The potential roles of chemokines and inflammatory or immune cells in nonhealing diabetic wounds, including impairments in growth factor expression, angiogenesis, extracellular matrix formation, and reepithelialization, are examined.