Vision of the body modulates somatosensory intracortical inhibition

The magnitude of somatosensory evoked potentials (SEPs) elicited by simultaneous electrical stimulation of adjacent digits is generally less than the sum of potentials evoked by stimulation of each digit individually. This under-additivity suggests suppression between representations of adjacent skin regions and may reflect a process of lateral inhibition by interneurons in somatosensory cortex. Given that simply viewing the body enhances tactile acuity and that tactile acuity depends on cortical lateral inhibition, we investigated how viewing the body modulates suppressive interactions between simultaneous afferent volleys from adjacent fingers. We recorded SEPs evoked by electrical stimulation of the right index and middle fingers, either individually or simultaneously, while participants viewed either their own hand or an object. In between trains of electrical stimuli, participants discriminated the orientation of tactile gratings applied to either finger. Consistent with previous findings, viewing the hand enhanced tactile acuity. Furthermore, viewing the hand increased the suppression of the P50 potential due to simultaneous electrical stimulation of both fingers. Moreover, the visual enhancement of tactile performance correlated across participants with the visual modulation of suppression. These results demonstrate that vision enhances somatosensation by modulating activity of inhibitory interneuronal circuits in the somatosensory cortex.     

The Effects of Biliopancreatic Diversion on Type 2 Diabetes Mellitus in Patients with Mild Obesity (BMI 30�C35?kg/m2) and Simple Overweight (BMI 25�C30?kg/m2): A Prospective Controlled Study

Background

Beneficial effects of BPD on T2DM in BMI >35 kg/m² patients are far better than those in patients with BMI 25?C35. This study was aimed at investigating if a similar difference exists between patients with mild obesity (OB, BMI 30?C35) or simple overweight (OW, BMI 25?C30).

Methods

Fifteen OB (six M) and 15 OW (13 M), diabetic for ??3 years, with HbA1c ??7.5% despite medical therapy, underwent BPD. OB/OW: age 55.1?±?8.0/57.8?±?6.7 years, BMI 33.1?±?1.5/28.0?±?1.3 kg/m², diabetes duration 11.6?±?8.0/11.1?±?6.1 years, insulin therapy 4/8 p. FSG and HbA1c were determined preoperatively and up to 2 years. Insulin resistance and beta-cell function were explored by means of HOMA-IR and IVGTT (AIR). Thirty-eight diabetic patients on medical therapy served as controls.

Results

Mean BMI stabilized around 27 since the 4th month in OB, and 24 since 1st month in OW. FSG in OB/OW preop, 1, 12, 24 months: 234?±?76/206?±?62 mg/dL, 154?±?49/176?±?75, 131?±?32/167?±?48, 134?±?41/154?±?41 (cross-sectional n.s. at all times); HbA1c: 9.5?±?1.6/9.1?±?1.3, 7.3?±?1.1/7.3?±?1.2, 5.9?±?0.6/7.1?±?1.1 (p?p?Conclusions Significantly different BPD effect, thus biological severity of T2DM, also exists between mildly obese and simply overweight patients. The rise of AIR allows hoping that an increase of beta-cell mass may occur in the long run. ClinicalTrials.gov Identifier: NCT00996294     

Using a combination of MLPA kits to detect chromosomal imbalances in patients with multiple congenital anomalies and mental retardation is a valuable choice for developing countries

Conventional karyotyping detects anomalies in 3-15% of patients with multiple congenital anomalies and mental retardation (MCA/MR). Whole-genome array screening (WGAS) has been consistently suggested as the first choice diagnostic test for this group of patients, but it is very costly for large-scale use in developing countries. We evaluated the use of a combination of Multiplex Ligation-dependent Probe Amplification (MLPA) kits to increase the detection rate of chromosomal abnormalities in MCA/MR patients. We screened 261 MCA/MR patients with two subtelomeric and one microdeletion kits. This would theoretically detect up to 70% of all submicroscopic abnormalities. Additionally we scored the de Vries score for 209 patients in an effort to find a suitable cut-off for MLPA screening. Our results reveal that chromosomal abnormalities were present in 87 (33.3%) patients, but only 57 (21.8%) were considered causative. Karyotyping detected 15 abnormalities (6.9%), while MLPA identified 54 (20.7%). Our combined MLPA screening raised the total detection number of pathogenic imbalances more than three times when compared to conventional karyotyping. We also show that using the de Vries score as a cut-off for this screening would only be suitable under financial restrictions. A decision analytic model was constructed with three possible strategies: karyotype, karyotype + MLPA and karyotype + WGAS. Karyotype + MLPA strategy detected anomalies in 19.8% of cases which account for 76.45% of the expected yield for karyotype + WGAS. Incremental Cost Effectiveness Ratio (ICER) of MLPA is three times lower than that of WGAS, which means that, for the same costs, we have three additional diagnoses with MLPA but only one with WGAS. We list all causative alterations found, including rare findings, such as reciprocal duplications of regions deleted in Sotos and Williams-Beuren syndromes. We also describe imbalances that were considered polymorphisms or rare variants, such as the new SNP that confounded the analysis of the 22q13.3 deletion syndrome.     

A novel microdeletion in the IGF2/H19 imprinting centre region defines a recurrent mutation mechanism in familial Beckwith-Wiedemann syndrome

The overgrowth disorder Beckwith-Wiedemann syndrome (BWS) is associated with dysregulation of imprinted genes at chromosome 11p15.5. The molecular defects are heterogeneous but most of the cases are associated with defective DNA methylation at either one of two Imprinting Control Regions (IC1 and IC2) or Uniparental paternal Disomy (UPD) at 11p15.5. In rare cases, the BWS phenotype has been found associated with maternal transmission of IC1 microdeletions. We describe a family with a novel 1.8 kb deletion that is associated with hypermethylation at IC1. The mutation results from recombination between highly homologous sequences containing target sites for the zinc-finger protein CTCF (CTSs). This finding supports the hypothesis that the function of IC1 and the penetrance of the clinical phenotype depend on the spacing of the CTSs resulting from recombination in the mutant allele.     

The diagnostic value of VEGF expression in the renal parenchyma tumors

Tumor angiogenesis emerged as an important concept in cancer therapy over two decades ago, and was extensively studied by the discovery of VEGF family members. VEGF, also known as vascular permeability factor, is a generic name for VEGF-A, which is one of the members involved in angiogenesis. VEGF is the most important angiogenic factor, with significant effects on tumor angiogenesis. Tumor expression of VEGF was not the first angiogenesis indicator, but a growing number of studies have demonstrated that VEGF could be a prognostic factor, independent even from microvascular density, which is increased by its expression. Renal parenchyma tumors are a heterogeneous group of malignancies, difficult to classify or monitor, which prompts for the assessment of novel markers useful for the investigation of tumor histogenesis or prognostic assessment. VEGF expression in renal parenchyma tumors is poorly studied, with most of the articles published so far focusing on antiangiogenic usage in renal carcinoma therapy. The aim of this study is to detect the expression pattern of VEGF in renal parenchyma tumors by immunohistochemistry.     

Atypical variant of lichen planus mimicking normal skin histology

We present the case of a 69-year-old Caucasian and non-smoker patient with erythematous, itchy, violaceous lesions on the ankles, wrists, lower legs, forearms and trunk developed within 15 months. Her condition was diagnosed as prurigo and she was treated for a long period of time with antihistaminic drugs, with no resolution of lesions. In October 2008, she presented to a Private Practice of Dermatology in Timisoara. The dermatologist noticed the development of violaceous lesions on her trunk. The patient had similar lesions on the ankles, wrists, lower legs, and forearms for the last eight months. At physical examination many hyperpigmented, 1 to 6 cm, thin plaques were present on the flanks, shoulders, and infra-mammary area. There was no vaginal involvement. This eruption had a good response to topical glucocorticoids, but recurred multiple times after discontinuation of treatment. A biopsy specimen showed some histopathological features of lichen planus.