What might cervical vestibular–evoked myogenic potential abnormalities mean in essential tremor?

Aim/background

Essential tremor (ET) is one of the most common movement disorders. However, its pathogenesis is unclear. Human vestibular reflexes are essential not only for gait and posture but also for goal-directed voluntary movements. In this study, cervical vestibular–evoked myogenic potentials (cVEMPs), the electrophysiological equivalent of the vestibulo-collic reflex was studied in ET patients to understand the interaction between the tremor network and the vestibular neural pathways.

Methods

cVEMPs were recorded in 40 ET patients and 40 age and sex-matched healthy controls (HCs). The latencies of peaks p13 and n23 and peak-to-peak amplitude of p13-n23 were measured.

Results

There was no statistically significant difference between the p13 latencies of the HC and ET groups (p 0.79 and p 0.23 for the right and left sides respectively). n23 latency was shortened bilaterally in the ET group (p 0.009 and p 0.02 for the right and left sides respectively). p13-n23 amplitudes of the ET patients were bilaterally reduced when compared with the HC (p <0.001 and p 0.001 for the right and left sides respectively).

Conclusion

Information provided by vestibular afferents is crucial in the control of voluntary movements in humans. Despite this silent but significant effect, the role of the vestibular system in movement disorders is often overlooked. In this study, it was found that cVEMP responses reflecting the activity of the vestibulo-collic pathway were affected in ET which can be either caused by dysfunctional structures or pathways responsible from ET or an additional disorder of vestibular information processing in these patients.

     

Cooperative effect of GNB3 825C>T and GPIIIa PI(A) polymorphisms in enhanced platelet aggregation

Introduction: Platelet aggregation contributes to various thrombembolic disorders. Environmental factors affect platelet aggregability but only partially explain the interindividual variability in aggregation. While the platelet glycoprotein IIb/IIIa is involved in the pathogenesis of acute coronary syndromes whereas most platelet activating stimuli act via G Protein coupled receptors we investigated whether the 825C>T polymorphism of the gene GNB3 encoding the G protein β3 subunit together with the platelet glycoprotein (GP) IIIa Pl(A) polymorphism are predictive of platelet aggregability on stimulation with various agonists acting via GPCRs. Materials and methods: Platelet aggregation was measured by turbidometry in 150 non-smoking individuals aged 18–40 years at a density of 2×10⁵ platelets/μl with various agonists according to the method of Born. Genotypes of the GNB3 825C>T and glycoprotein IIb/IIIa PI(A) polymorphisms were determined using Pyrosequencing technology and restriction analysis. All functional studies were completed within 3 h. The data were analysed by Student's t-test for paired data. Results: Low concentrations of agonists resulted in enhanced platelet aggregation in subjects with the GNB3 CC-genotype compared to carriers of a 825T-allele. This effect was further enhanced in carriers of the GPIIIa Pl(A2) allele (2 μM ADP: 42% vs. 19%, p=0.017; 1 μM U-46619: 51% vs. 30%, p=0.03; 5 μM epinephrine: 69% vs. 53%, p=0.025). No significant pattern of aggregation was observed on stratification by GPIIIa genotypes alone. Conclusions: Our findings indicate that two genetic markers contribute synergistically to increased platelet aggregation. This will help to identify patients at increased risk for thrombosis.     

Effect of sucking characteristics on breast milk creamatocrit

One of the problems in the care of healthy children is that mothers often give infant formulae to their normally growing infants in the first 4 months of life because they believe that they are unable to satisfy them. However, the association of fat content in breast milk with the sucking pattern of the infant is not clearly known. In order to determine whether the fat concentration of human milk was associated with sucking characteristics of the infants, 80 healthy 2-month-old babies and their mothers were included in the study. Milk creamatocrit was assessed at the beginning, at the first, fifth and 10th minutes and at the end of breast feeding. The creamatocrit values increased as the time elapsed from the beginning of breast feeding. There was an inverse relationship between milk volume and creamatocrit at both the beginning and the end of breast feeding (P < 0.05). The mean milk volume was higher and the mean creamatocrit at the end of breast feeding was lower in the infants whose 2-month weight gain was higher than the 75th percentile (75P) compared with those whose 2-month weight gain was lower than the 25th percentile (25P) (for milk volume 105 +/- 36 mL vs. 76 +/- 30 mL, respectively, P < 0.05; and for creamatocrit value 11.4 +/- 4.0 vs. 14.3 +/- 3.8, respectively, P < 0.05). Milk volume is the most important factor affecting weight gain of exclusively breast-fed babies, and fat concentration of human milk is not a primary determining factor in individual differences in weight gain of the infants and appears to be secondary to factors such as number of feeds per day, duration of breast feeding and the volume of milk sucked.     

Most reliable indices in differentiation between thalassemia trait and iron deficiency anemia

BACKGROUND: Iron deficiency anemia (IDA) and thalassemia trait (TT) are the most common forms of microcytic anemia. Some discrimination indices calculated from red blood cell indices are defined and used for rapid discrimination between TT and IDA. However, there has been no study carried out in which the validity of all of the defined indices are compared in the same patient groups. Youden's index is the most reliable method by which to measure the validity of a particular technique, because it takes into account both sensitivity and specificity. METHODS: We calculated eight discrimination indices (Mentzer Index, England and Fraser Index, Srivastava Index, Green and King Index, Shine and Lal Index, red blood cell (RBC) count, red blood cell distribution width and red blood cell blood distribution width index (RDWI)) in 26 patients with IDA and in 37 patients with beta TT (betaTT). We determined the number of correctly identified patients by using each discrimination index. We also calculated sensitivity, specificity, positive and negative predictive value and Youden's index of each discrimination index. RESULTS: None of the discrimination indices showed a sensitivity and specificity of 100%. Youden's indices of RBC count and RDWI were the highest with the value of 82 and 80%, respectively. Ninety percent and 92% of the patients were correctly identified with RBC and RDWI, respectively. CONCLUSIONS: Red blood cell count and RDWI are the most reliable discrimination indices in differentiation between betaTT and IDA.     

A Rare Complication of Adjustable Gastric Banding:Wernicke's Encephalopathy

Background:Wernicke'sencephalopathy is an uncommon complication seen after morbid obesity surgery. Neurological and cardiac symptoms can occur. Early and adequate replacement of thiamin is crucial. Methods: A patient, who was operated by adjustable silicone gastric banding had severe vomiting 1 week after the operation. Physical examination showed no abnormalities except neurological signs consisting of ataxia, disorientation and diplopia. All radiological and biochemical parameters were in the normal range. Result: After replacement of vitamin B₁ (thiamin) intravenously 20 mg twice daily, all the neurological signs regressed day by day. Oral thiamin pills have been continued. Conclusion: Wernicke's encephalopathy which occurs as a result of thiamin deficiency is a rare complication that has serious morbidity with rapidly progressing neurologic symptoms, and must be treated immediately. Surgeons who treat morbidly obese patients must follow the metabolic and nutritional status of the patient.     

Value of p53 protein in biological behavior of basal cell carcinoma and in normal epithelia adjacent to carcinomas

Mutations in p53 gene are the most frequent gene alterations in human cancer. In this study, we have used the monoclonal antibody (DO7) to evaluate the role of the p53 gene mutation in the progression of basal cell carcinomas towards invasion. We tested the positivity for p53 protein in tumor cells in six cases of basosquamous cell carcinoma (BSCC), in twelve cases of infiltrative basal cell carcinoma (IBCC) and twenty-four cases of non-infiltrative basal cell carcinoma (NIBCC) in order to evaluate its potential prognostic significance. We also tested the expression of p53 protein in normal epithelia adjacent to carcinomas in order to determine its role in tumor progression. p53 protein staining with some peripheral accentuation was identified in 42,9% of all groups. No correlation was found between the immunreactivity of p53 protein and recurrence, pattern of tumor, diameter of the tumors and sex. However, there were statistically significant differences in positivity of p53 protein in normal epithelia adjacent to carcinomas and age of patients (t value: 2,21; p: 0,034). Results of the study suggest that the increasein p53 mutation frequency of morphologically normal epidermis was related to age and was independent of the degree of differentiation of BCC.     

Isolation, culture, and characterization of endothelial cells from mouse glomeruli

BACKGROUND: Cloned glomerular endothelial cells (GENC) have many potential uses and applications in immunologic and physiologic studies. Propagation of GENC has been difficult and available homogeneous GENC, particularly from mice, are limited. Herein we report isolation, cloning, propagation, and characterization of GENC from mice. METHODS: tsA58 immorto mice were used to isolate glomerular cells. Glomeruli were isolated by differential sieving, and decapsulated explants were cultured in permissive and optimal conditions for endothelial cells. The primary cells from glomerular outgrowths were expanded, taking advantage of the temperature-sensitive tsA58 gene, and then the cells were allowed to undergo spontaneous transformation. The cells were then sorted using anti-CD31 antibodies and their capacity to uptake acetylated-low-density lipoprotein (LDL). Individual subclones isolated by patch cloning were characterized using multiple markers. RESULTS: One of the homogeneous clones was morphologically endothelial-like, positive for CD31, CD106, CD62E, CD54, and acetylated-LDL uptake, formed tubes, and was negative for epithelial and mesangial cell markers. The functional properties of this GENC clone appeared to be intact, and signaling pathway was not altered. Two of the clones displayed the characteristics of either visceral epithelial or mesangial cells. CONCLUSION: The identified clones should have utility in multiple areas of investigation.     

Biochemical bone markers in nephrotic children

In this study we evaluated the effects of high-dose corticosteroid (CS) therapy and the character of the nephrotic syndrome (NS) itself on bones in patients with normal glomerular filtration rate. We measured serum osteocalcin (OC), alkaline phosphatase (ALP), intact parathyroid hormone (iPTH), 25-hydroxyvitamin D, calcium (Ca), phosphorus (P), and magnesium (Mg) levels, and urinary Ca and protein excretion in nephrotic children during the active phase before (group Ia) and after CS treatment (group Ib). The results were compared with age-matched control subjects. A significant increase in urinary Ca excretion was observed after CS treatment. Serum ALP, OC, and iPTH levels were within normal limits at the time of study entry. However, both serum OC and ALP levels showed a significant decrease after the completion of CS treatment (OC from 13.6±9.2 ng/ml to 6.7±5.2 ng/ml and ALP from 151.8±60.2 U/l to 116±43.8 U/l). 25-Hydroxyvitamin D levels increased to 17.2±8.9 g/l from 9.9±6.9 g/l after CS treatment. The effects of recurrent use of CSs were assessed by dividing nephrotic patients into two subgroups: infrequent relapsers (IFR) and frequent relapsers (FR). The cumulative dose of CS was 28,125 mg/m² for IFR and 105,000 mg/m² for FR. The changes in OC, ALP, and 25-hydroxyvitamin D levels after CS treatment were significantly different between IFR and FR. We conclude that high-dose CS treatment causes a decrease in bone formation, as shown by the changes in OC and ALP levels. 25-Hydroxyvitamin D levels remained lower than control subjects after CS therapy. The higher the cumulative dose of CS used the more marked the changes in biochemical bone markers. The contribution of FR to baseline 25-hydroxyvitamin D levels needs further study.