Dynamics of Tibiofibular Syndesmosis in Correlation with the Level of the Syndesmotic Scress in Maisonneuvre Fractures of the Ankle - a Cadaver Study

Background: The objective of this study was to determine the level of the syndesmotic screw, the number of screws needed, and whether one or both cortices of tibia should be engaged to closely reproduce the physiological stability and elastic of the ankle mortise in syndesmotic rupture after Maisonneuve fractures. Material and Methods: Twelve fresh frozen cadaveric pairs of lower extremities were used for this study. The knee was exarticulated and soft tisue removed leaving the lateral and medial ankle ligaments intact. The tibiofibular syndesmosis was then sharply sectioned. All specimens were mounted in an Instron 2000 material testing machine. An axial loading of 500 N was applied. Syndesmotic diastasis was measured by a linear transducer system. The specimens were divided into three groups. In group I, the specimens were instrumented with one syndesmotic screw 2.5 cm above tibia plafond. In group II, the same procedure was performed as in group I with the syndesmotic screw positioned 4 cm above tibia plafond. In group III, the syndesmosis was fixed in each pair with two screws 2.5 and 4 cm above tibia plafond. In all groups, the screws were positioned randomly through three cortices on the one side and through four cortices on the contralateral side. Results: Significant difference was observed between the application of one or two screws through three or four cortical shells on one side and the level of the screw on the other. Conclusions: According to the results of this study, we recommend to use one screw through four cortices 2.5 cm above the tibia plafond.     

Temporal limits of long-range phase discrimination across the visual field

When two flickering sources are far enough apart to avoid low-level motion signals, phase judgment relies on the temporal individuation of the light and dark phases of each source. The highest rate at which the individuation can be maintained has been referred to as Gestalt flicker fusion [Van de Grind, W. A., Grüsser, O. -J., & Lunkenheimer, H. U. (1973). Temporal transfer properties of the afferent visual system. Psychophysical, neurophysiological and theoretical investigations. In R. Jung (Ed.), Handbook of sensory physiology (Vol. VII/3, pp. 431-573). Berlin: Springer, Chapter 7] and this has been taken as a measure of the temporal resolution of attention [Verstraten, F. A., Cavanagh, P., & Labianca, A. T. (2000). Limits of attentive tracking reveal temporal properties of attention. Vision Research, 40, 3651-3664; Battelli, L., Cavanagh, P., Intriligator, J., Tramo, M. J., Henaff, M. A., Michel, F., et al. (2001). Unilateral right parietal damage leads to bilateral deficit for high-level motion. Neuron, 32, 985-995]. Here we examine the variation of the temporal resolution of attention across the visual field using phase judgments of widely spaced pairs of flickering dots presented either in the upper or lower visual field and at either 4 degrees or 14 degrees eccentricity. We varied inter-dot separation to determine the spacing at which phase discriminations are no longer facilitated by low-level motion signals. Our data for these long-range phase judgments showed that temporal resolution decreases only slightly with increased distance from center of gaze (decrease from 11.4 to 8.9 Hz between 4 degrees to 14 degrees ), and does not differ between upper and lower visual fields. We conclude that the variation of the temporal limits of visual attention across the visual field differs markedly from that of the spatial resolution of attention.     

Significance of abnormal myocardial perfusion scintigraphy in young adult patients with SLE

Objectives  

Detection of subclinical coronary artery disease (CAD) is a potential challenge in patients with systemic lupus erythematosus (SLE) and it is suggested that myocardial perfusion single photon emission computerized tomography (SPECT) is more sensitive than exercise test in this setting. However, the significance of perfusion abnormalities in SLE patients is not well known. In this study, we evaluated the prognostic significance of myocardial perfusion defects in patients with SLE.     

Gene expression profiling reveals alteration of caspase 6 and 14 transcripts in normal skin of keloid-prone patients

Excessive scar formation in keloids points to altered tissue modeling and repair mechanisms. Dysregulation of cytokine and apoptotic cascades and their downstream signaling pathways might have a role in keloid development. Total RNA was isolated from biopsied keloidal tissue and adjacent normal skin of black patients, white patient’s scars, and normal skin of black and white patients, with normal wound healing. Apoptosis, cytokine and NFkB pathway microarrays were used to study and compare gene expression levels. Real-time PCR was used to verify microarray results in original samples and a separate, validation-set of samples. Significant differences were observed in the expression levels of members of caspase, cytokines and MAP kinase pathways, between the normal skin of keloid-prone and normal skin of keloid-resistant patients. Specifically, expression of caspase 6, and caspase 14 genes were different between normal skin of keloid-prone individuals and normal skin of keloid-resistant patients. Our results suggest that normal skin of keloid-prone individuals constitutively expresses a distinct gene profile which might contribute to their susceptibility to develop keloids.     

Effects of different periods of renal ischemia on liver as a remote organ

AIM： To assess the hepatic changes after induction of different periods of renal ischemia. METHODS： Rats were subjected to either sham operation or ischemia （30, 45 and 60 min） followed by 60 min reperfusion. Liver and renal functional indices were measured. Hepatic glutathione （GSH） and ferric reducing antioxidant power levels and the concentration of interleukin （IL）-10 and tumor necrosis factor （TNF-α） were evaluated. Portions of liver and kidney tissues were fixed for histological evaluation. RESULTS： Forty-five minutes renal ischemia followed by 60 min reperfusion caused significant changes in liver structure and a significant reduction in renal function. These rats showed a significant decrease in liver GSH, as well as a significant increase in TNF-α and IL-10 concentrations. These results demonstrated that renal ischemia caused changes in liver histology, function, oxidative stress and inflammatory status, which led to a reduction in hepatic antioxidant capacity. With 30 min ischemia, the magnitude of these changes was less than those with 45 or 60 min ischemia. CONCLUSION： A minimum of 45 min ischemia is needed to study the effects of renal injury on the liver as a remote organ.     

Prevalence and risk factors of gastroesophageal reflux disease in Qashqai migrating nomads, southern Iran

AIM： To investigate the prevalence and risk factors of gastroesophageal reflux disease （GERD） symptoms in Qashqai migrating nomads with a different life style in Fars province, southern Iran. METHODS： In summer 2006, 748 Qashqai migrating nomads aged 25 years or more were enrolled using a multiple-stage stratified cluster random sampling method. A questionnaire consisting of demographic characteristics, lifestyle and GERD symptoms （heartburn, regurgitation, chest pain, dysphagia, hoarseness and cough） as completed for each subject. RESULTS： The questionnaire was completed in 717 subjects. The prevalence rate of GERD, defined as reflux occurring at least one time per week in the preceding year, was 33% （237 subjects）. The prevalence was higher in older individuals （36.0% vs 28.9%, P 〈 0.05） and in those with other gastrointestinal complaints （51.0% vs 27.8%, P 〈 0.001）, but not different in obese and non-obese subjects. It was also higher in those consuming fruits and vegetables more than once a week （36.2% vs 17.3%, P 〈 0.001）. GERD had a positive correlation with smoking （42.1% vs 27.8%, P 〈 0.001）, but a negative relation with non-alcoholic beverages. The association between GERD and non-steroidal antiinflammatory drugs （NSAIDs） consumption was also significant （40.2% vs 25.4%, P 〈 0.001）. CONCLUSION： The prevalence of GERD （33%） is very high in Qashqai migrating nomads which may be due to a lower socioeconomic and educational level of these people and difference in the life style. Older age, frequent consumption of fruits and vegetables, smoking and NSAIDs are risk factors for GERD in this population.     

Graves' ophthalmopathy and gene polymorphisms in interleukin-1α, interleukin-1β, interleukin-1 receptor and interleukin-1 receptor antagonist

Purpose: Interleukin‐1 (IL‐1) is known to have an important role in pathogenesis of Graves' ophthalmopathy (GO). Polymorphisms in IL‐1 gene have been associated with autoimmune reactions. This study aimed to investigate the association of GO with single‐nucleotide polymorphisms (SNPs) in the IL‐1 family (IL‐1α, IL‐1β, IL‐1 receptor [IL‐1R] and IL‐1 receptor antagonist [IL‐1RA]). Methods: A total of 57 patients of Graves' disease without GO, 50 patients with GO and 140 healthy controls were enrolled. Patients were recruited consecutively from the outpatient endocrine clinic of a large university general hospital. Cytokine typing was performed by the polymerase chain reaction with sequence‐specific primers assay. The allele and genotype frequencies of the following polymorphisms were determined: IL‐1α (?889C/T), IL‐1β (?511C/T), IL‐1β (+3962C/T), IL‐1R (Pst‐1 1970C/T) and IL‐1RA (Mspa‐1 11100C/T). Genotype distributions among patients were in Hardy–Weinberg equilibrium for all polymorphisms. Results: Among the five SNPs studied, the frequencies of the T allele and the TT genotype of IL‐1α (?889C/T) were significantly higher among patients with GO than those without GO (odds ratio [OR] = 2.16, 95% confidence interval [CI] = 1.25–3.74; P = 0.006 and 5.67, 95% CI = 1.66–49.34; P = 0.005, respectively). For IL‐1RA (Mspa‐1 11100C/T), the frequencies of the C allele and the CC genotype were significantly higher among patients with GO (OR = 2.31, 95% CI = 1.34–4.00; P = 0.004 and 6.73 95% CI = 1.94–23.36; P = 0.004, respectively; P < 0.01). No significant association was found for other SNPs. Conclusion: This is the first study to show a positive correlation between polymorphisms in the IL‐1α and IL‐1RA genes and susceptibility to GO. These findings promote further research into genetic correlates of GO.     

Monitoring of Cytomegalovirus Reactivation in Bone Marrow Transplant Recipients by Real-time PCR

Cytomegalovirus (CMV) has been recognized as the most important viral pathogen in persons undergoing bone marrow transplantation (BMT). The aim was to develop a quantitative PCR assay to quantify CMV DNA in peripheral blood leukocytes (PBLs) of bone marrow transplantation (BMT) patients. An in-house real-time PCR assay based on TaqMan technology was developed to monitor the quantity of CMV DNA in PBLs of the BMT recipients. Sequential blood samples (415 specimens) were collected from 43 patients as weekly intervals until day 100 after transplantation. The CMV DNA was quantified in parallel with the pp65 antigenemia assay in PBL samples. Viral reactivation occurred in 51% and 41.8% of the recipients as detected by RQ-PCR and antigenemia assays respectively. There was a significant correlation between both assays (P < 0.0001); however, the RQ-PCR was more sensitive than the antigenemia. CMV DNA was detected by the RQ-PCR by a median of 14 days earlier than the antigenemia. Preemptive therapy was implemented in the antigenemia positive cases. The administration of ganciclovir led to a rapid decrease in the viral load. After preemptive therapy, the antigenemia achieved a negative result earlier than the RQ-PCR assay (a median of 17.5 days). An increase of viral load in both quantitative assays and of cyclosporine serum level were identified as the most significant risk factors for CMV reactivation. The quantitative CMV PCR might be a useful tool for monitoring the CMV reactivation and guiding the efficacy of the CMV preemptive therapy in BMT recipients.