Association of EGFR c.2073A > T polymorphism with decreased risk of diffusely infiltrating astrocytoma in a Brazilian case-control study

Epidermal growth factor receptor (EGFR) gene overexpression has been implicated in the development of many types of tumors, including glioblastomas, the most frequent diffusely infiltrating astrocytomas. However, little is known about the influence of the polymorphisms of EGFR on EGFR production and/or activity, possibly modulating the susceptibility to astrocytomas. This study aimed to examine the association of two EGFR promoter polymorphisms (c.-191C > A and c.-216G > T) and the c.2073A > T polymorphism located in exon 16 with susceptibility to astrocytomas, EGFR gene expression and survival in a case-control study of 193 astrocytoma patients and 200 cancer-free controls. We found that the variant TT genotype of the EGFR c.2073A > T polymorphism was associated with a significantly decreased risk of astrocytoma when compared with the AA genotype [sex- and age-adjusted odds ratio 0.51, 95% confidence interval 0.26-0.98]. No association of the two promoter EGFR polymorphisms (or combinations of these polymorphisms) and risk of astrocytomas, EGFR expression or survival was found. Our findings suggest that modulation of the EGFR c.2073A > T polymorphism could play a role in future therapeutic approaches to astrocytoma. (Int J Biol Markers 2008; 23: 140-6)

Ultrasound features of carpal tunnel syndrome: a prospective case-control study

Purpose The purpose of the study was to examine the most adequate cut-off point for median nerve cross-sectional area and additional ultrasound features supporting the diagnosis of carpal tunnel syndrome (CTS). Material and methods Forty wrists from 31 CTS patients and 63 wrists from 37 asymptomatic volunteers were evaluated by ultrasound. All patients were women. The mean age was 49.1 years (range: 29-78) in the symptomatic and 45.1 years (range 24-82) in the asymptomatic group. Median nerve cross-sectional area was obtained using direct (DT) and indirect (IT) techniques. Median nerve echogenicity, mobility, flexor retinaculum measurement and the anteroposterior (AP) carpal tunnel distance were assessed. This study was IRB-approved and all patients gave informed consent prior to examination. Results In CTS the median nerve cross-sectional area was increased compared with the control group. Median nerve cross-sectional area of 10 mm(2) (DT) and 9 mm(2) (IT) had high sensitivity (85% and 88.5%, respectively), specificity (92.1% and 82.5%) and accuracy (89.3% and 82.5%) in the diagnosis of CTS. CTS patients had an increased carpal tunnel AP diameter, flexor retinaculum thickening, reduced median nerve mobility and decreased median nerve echogenicity. Conclusion Ultrasound assists in the diagnosis of CTS using the median nerve diameter cut-off point of 10 mm(2) (DT) and 9 mm(2) (IT) and several additional findings.

Immediate and lasting improvements in weight distribution seen in baropodometry following a high-velocity, low-amplitude thrust manipulation of the sacroiliac joint

The biomechanics of the sacroiliac joint makes the pelvic segment responsible for proper weight distribution between lower extremities; however, it is known to be susceptible to altered mobility. The objective of this study was to analyze baropodometric responses following thrust manipulation on subjects with sacroiliac joint restrictions. Twenty asymptomatic subjects were submitted to computerized baropodometric analysis before, after, and seven days following sacroiliac manipulation. The variables peak pressure and contact area were obtained at each of these periods as the average of absolute values of the difference between the right and left foot based on three trials. Data revealed significant reduction only in peak pressure immediately after manipulation and at follow-up when compared to pre-manipulative values (p < 0.05). Strong correlation was found between the dominant foot and the foot with greater contact area (r - 0.978), as well as between the side of joint restriction and the foot with greater contact area (r = 0.884). Weak correlation was observed between the dominant foot and the foot with greater peak pressure (r = 0.501), as well as between the side of joint restriction and the foot with greater peak pressure (r = 0.694). The results suggest that sacroiliac joint manipulation can influence peak pressure distribution between feet, but contact area does not seem to be related to the biomechanical aspects addressed in this study. (C) 2011 Elsevier Ltd. All rights reserved.

Electrical Stimulation During Gait Promotes Increase of Muscle Cross-sectional Area in Quadriplegics: A Preliminary Study

Increases in muscular cross-sectional area (CSA) occur in quadriplegics after training, but the effects of neuromuscular electrical stimulation (NMES) along with training are unknown. Thus, we addressed two questions: (1) Does NMES during treadmill gait training increase the quadriceps CSA in complete quadriplegics?; and (2) Is treadmill gait training alone enough to observe an increase in CSA? Fifteen quadriplegics were divided into gait (n = 8) and control (n = 7) groups. The gait group performed training with NMES for 6 months twice a week for 20 minutes each time. After 6 months of traditional therapy, the control group received the same gait training protocol but without NMES for an additional 6 months. Axial images of the thigh were acquired at the beginning of the study, at 6 months (for both groups), and at 12 months for the control group to determine the average quadriceps CSA. After 6 months, there was an increase of CSA in the gait group (from 49.8 +/- A 9.4 cm(2) to 57.3 +/- A 10.3 cm(2)), but not in the control group (from 43.6 +/- A 7.6 cm(2) to 41.8 +/- A 8.4 cm(2)). After another 6 months of gait without NMES in the control group, the CSA did not change (from 41.8 +/- A 8.4 cm(2) to 41.7 +/- A 7.9 cm(2)). The increase in quadriceps CSA after gait training in patients with chronic complete quadriplegia appears associated with NMES.

Electromyographic Analysis of Paravertebral Muscles in Patients with Idiopathic Scoliosis

Study Design. Prospective clinical electromyographic study in adolescents with idiopathic scoliosis and control group. Objective. To evaluate electromyographic amplitude from erector spinae muscles of patients with idiopathic scoliosis in comparison with control volunteers without spinal deformities. Summary of Background Data. Previous studies have indicated an increased electromyographic activity in paravertebral muscles in the convex side of the scoliotic curvature. However, in previous studies there is the absence or poor description of methods used, and some studies were conducted before the recording and processing recommendations for surface electromyographic signals had been described. Methods. Thirty individuals, matched by sex, age, and body mass index, were divided into two groups: scoliosis and control. The electric activity of the erector spinae muscles was determined by surface electromyography on both sides of the three levels of spine: T8, L2, and L5. Results. Normalized electromyographic amplitudes of erector spinae muscles, in the convex and concave sides of the apex region of the scoliotic curve in the thoracic and lumbar regions, were not significantly different. Also, there was no significant difference between the muscles of these regions when the scoliosis group was compared with the control group. The erector spinae muscle at the L5 level, representing the lower vertebral limit of the lumbar scoliotic curve, had significantly higher electromyographic activity on the convex side. However, the same alteration was shown in the control group homologous muscle (on the left side). Conclusion. Erector spinae muscles on the convex and concave sides at the curvature apex in patients with idiopathic scoliosis and small magnitude of curves did not show significant differences in electromyographic amplitude. Future studies should evaluate whether intragroup activation differences, at the L5 level in 80% of the maximum voluntary isometric contractions with predominance of the left side of the vertebral column, have any relation to the condition.

Major histocompatibility complex (MHC) class II but not MHC class I molecules are required for efficient control of Strongyloides venezuelensis infection in mice

P>Strongyloides stercoralis is an intestinal nematode capable of chronic, persistent infection and hyperinfection of the host; this can lead to dissemination, mainly in immunosuppressive states, in which the infection can become severe and result in the death of the host. In this study, we investigated the immune response against Strongyloides venezuelensis infection in major histocompatibility complex (MHC) class I or class II deficient mice. We found that MHC II(-/-) animals were more susceptible to S. venezuelensis infection as a result of the presence of an elevated number of eggs in the faeces and a delay in the elimination of adult worms compared with wild-type (WT) and MHC I(-/-) mice. Histopathological analysis revealed that MHC II(-/-) mice had a mild inflammatory infiltration in the small intestine with a reduction in tissue eosinophilia. These mice also presented a significantly lower frequency of eosinophils and mononuclear cells in the blood, together with reduced T helper type 2 (Th2) cytokines in small intestine homogenates and sera compared with WT and MHC I(-/-) animals. Additionally, levels of parasite-specific immunoglobulin M (IgM), IgA, IgE, total IgG and IgG1 were also significantly reduced in the sera of MHC II(-/-) infected mice, while a non-significant increase in the level of IgG2a was found in comparison to WT or MHC I(-/-) infected mice. Together, these data demonstrate that expression of MHC class II but not class I molecules is required to induce a predominantly Th2 response and to achieve efficient control of S. venezuelensis infection in mice.

CCR2 receptor is essential to activate microbicidal mechanisms to control Toxoplasma gondii infection in the central nervous system

Chemokines comprise a structurally related family of cytokines that regulate leukocyte trafficking. Because infection with Toxoplasma gondii can induce an important inflammatory reaction that, if left uncontrolled, can lead to death, we investigated the role of the chemokine receptor CCR2 in T gondii infection. We orally infected CCR2(-/-) mice with five ME-49 T gondii cysts and monitored morbidity, survival, and immune response thereafter. The CCR2(-/-) mice displayed higher susceptibility to infection as all mice died on day 28 after infection. Despite similar Th1 responses, a more evident anti-inflammatory response was induced in the peripheral organs of CCR2(-/-) mice compared with wild-type C57BL/6 mice. Additionally, CCR2-/- mice presented greater parasitism and a milder inflammatory reaction in their peripheral organs with lesser CD4(+) and MAC-1(+) and greater CD8(+) cell migration. The parasite load decreased in these organs in CCR2(-/-) mice but remained uncontrolled in the central nervous system. Additionally, we observed down-regulated inducible nitric oxide synthase expression in peripheral organs from CCR2(-/-) mice that was associated with a small nitric oxide production by spleen macrophages. In conclusion, in the absence of CCR2, another mechanism is activated to control tissue parasitism in peripheral organs. Nevertheless, CCR2 is essential for the activation of microbicidal mediators that control T gondii replication in the central nervous system.