Cortical evoked potentials and somatosensory perception in chronic spinal cord injury patients

The correlation between somatosensory evoked potentials (SEPs) and sensory perception was studied in 110 patients with traumatic chronic spinal cord lesions. Perception thresholds over the legs for light touch, vibratory sensibility, temperature and thermal pain were tested together with recordings of tibial and peroneal SEPs. Tibial nerve SEPs correlated better with sensory perception than peroneal nerve SEPs. Normal tibial nerve SEPs were not present with absent or trace vibratory sensibility and vice versa. However, we found many exceptions to the correlation between temperature and pain perception and SEPs. Light touch, vibratory sensibility, and SEPs were highly correlated between each other, while temperature and pain perception correlated poorly to these other modalities. This represents an evident segregation of touch perception, vibratory sensibility and SEPs, which are thought to share dorsal columns as a common ascending pathway, and temperature and pain perception known to be related to the spinothalamic system.     

Vascular calcification and atherosclerosis in hemodialysis patients: what can we learn from the routine clinical practice?

BACKGROUND: Hemodialysis (HD) patients are at increased risk for arterial intimal (AIC) and medial calcification (AMC). METHODS: In a cross-sectional study on 153 HD patients we evaluated the presence of AIC and AMC using plain radiography of the pelvis and the presence of atherosclerotic lesions using high-resolution B-mode ultrasonography of the common carotid arteries (CCA). RESULTS: The radiography of the pelvis confirmed the frequent presence of AIC (35.3%) and AMC (35.9%) in our HD patients. Arterial calcification was absent (non calcified-NC) in a minority of patients (28.8%). Patients with AIC had significantly higher prevalence of atherosclerotic plaques on CCA (78.6%) compared with both other groups and a higher number of documented atherosclerotic complications, such as cardiovascular (85.2%), cerebrovascular (33.3%) and peripheral arterial disease (38.9%) in comparison with the NC patients. According to the 1-year calculated data from patient records, there were no significant differences in the specific HD risks, such as the dose of prescribed calcium carbonate and vitamin D3, serum levels of calcium, phosphate, calcium-phosphate product and intact parathyroid hormone. All four bone metabolism markers within the range proposed by K/DOQI guidelines were achieved in 9.3%, 14.5% and 20.4% in the AIC, AMC and NC group, respectively. CONCLUSIONS: Patients with AIC and AMC are frequently found in the HD population. Screening for arterial calcifications in chronic kidney disease patients is suggested even in the early pre-dialysis period. The highest proportion of patients within the guidelines proposed range for bone and mineral metabolism markers was observed in the NC group. A longer period of data analysis is required in order to evaluate the possible role of some traditional and HD-specific risk factors for the development of arterial calcifications. The achievement of the K/DOQI guidelines is an important issue in the prevention of those conditions.     

Therapeutic efficacy of bilateral prefrontal slow repetitive transcranial magnetic stimulation in depressed patients with Parkinson's disease: an open study.

Recent studies have suggested that both high- and low-frequency repetitive transcranial magnetic stimulation (rTMS) have antidepressant effects in patients with major depression. We conducted an open study to assess the effects of slow rTMS on mood changes in patients with depression associated with Parkinson's disease (PD). Ten depressed patients with PD (four with major depression and six with dysthymia) received daily sessions of rTMS (frequency, 0.5 Hz; pulse duration, 0.1 msec; field intensity, 10% above the motor threshold) over both prefrontal regions (a total of 100 stimuli per prefrontal region daily) over 10 consecutive days. This treatment resulted in a moderate but significant decrease in scores of the Hamilton Depression Rating Scale (33-37%) and the Beck Depression Inventory (24-34%), which persisted 20 days after finishing the stimulation. In parallel, we observed mild improvement (18-20%) of motor symptoms. No significant adverse effects were reported. These preliminary results suggest the therapeutic potential of daily prefrontal low-frequency rTMS (0.5 Hz) in depression associated with PD.     

Pregnancy-induced obsessive compulsive disorder: a case report

Pregnancy is a well-recognised risk factor in precipitating obsessive-compulsive disorder. We present and discuss a case with the onset of obsessive-compulsive disorder in the fourth month of gestation, which fully recovered two weeks after delivery. The phenomenology of the observed disorder was similar to earlier reports of obsessive-compulsive disorder in pregnancy, i.e. the obsessions and compulsions were predominantly related to the concern of contaminating the foetus resulting in washing compulsions. Despite the initial success with anti-obsessional drugs, the patient stopped the medication in the last month of gestation. Nevertheless, she fully recovered two weeks after the delivery without any psychiatric intervention. There were no obsessive-compulsive symptoms at one-year follow up. The possible mechanisms involved in the aetiology of this case, and future research directions in understanding the role of pregnancy in OCD are discussed.     

In vitro function and phagocytosis of galactosylated platelet concentrates after long-term refrigeration

BACKGROUND: Short-term refrigeration of platelets (PLTs) in the absence of plasma results in their rapid clearance after transfusion. Blocking beta-N-acetylglucosamine (beta-GlcNAc) residues of glycoprotein Ibalpha (GPIbalpha) with galactose prevents binding of refrigerated human and mouse PLTs to macrophages and prolongs the circulation times of refrigerated mouse PLTs. PLT-associated galactosyltransferase efficiently galactosylates chilled PLTs in the presence of its substrate UDP-galactose is added to PLT-rich plasma. STUDY DESIGN AND METHODS: To characterize the hemostatic function of refrigerated and galactosylated human PLTs processed in the blood bank, PLT aggregation was studied in vitro under static and flow conditions and expression of integrin beta3 (CD61), CD62P (P-selectin), GPIbalpha (CD42b), annexin V binding, and integrin alphaIIbeta3 activation with flow cytometry. Affinity of macrophages for galactosylated refrigerated PLTs was evaluated with THP-1 cells, which recognize and phagocytize refrigerated PLTs. RESULTS: PLTs refrigerated and galactosylated for 14 days 1) maintained their ability to aggregate when exposed to agonists in a standard aggregometry assay, 2) showed less pronounced changes in surface expression of GPIbalpha compared with room temperature (RT)-stored PLTs, 3) increased P-selectin expression, and 4) were poorly phagocytized by differentiated THP-1 cells in vitro. In addition, it is shown that refrigeration of PLTs does not affect their adhesive properties under in vitro flow conditions. CONCLUSION: It is shown that refrigerated human PLTs retain in vitro function better than RT PLTs during storage and demonstrate that galactosylation prevents recognition of stored refrigerated PLTs by macrophages in vitro.     

Interleukin-3 promotes proliferation and differentiation of human hematopoietic stem cells but reduces their repopulation potential in NOD/SCID mice

In the present study we explored systematically the influence of human interleukin-3 (IL-3) on the cord blood (CB) cell-derived production of human hematopoietic cells in the bone marrow, blood, and spleen of chimeric nonobese/severe combined immunodeficient mice ((NOD/SCID) mice. CB mononuclear cells and MACS-enriched CB CD34(+) cells were injected into irradiated NOD/SCID mice. The mice were additionally transplanted with a stably transfected rat fibroblast cell line expressing the human IL-3 gene (Rat-IL-3) constitutively, or with the nontransfected rat fibroblast cell line as a control (Rat-1). Rat-IL-3 mice displayed a higher engraftment of human hematopoietic cells in bone marrow, spleen, and peripheral blood compared with mice with Rat-1 cotransplantation. When we transplanted their total bone marrow cell population into secondary mice, surprisingly, mice transplanted with bone marrow cells from Rat-1 mice displayed a higher proportion of human hematopoietic cells compared with Rat-IL-3 mice. As expected, bone marrow cultures (BMCs) from Rat-IL-3 mice contained a higher proportion of human cells than Rat-1 bone marrow cells. However, when BMCs were passaged to new flasks, we observed a higher proportion of human cells in BMCs from Rat-1 mice compared with BMCs from Rat-IL-3 mice. IL-3 promotes the proliferation and differentiation of hematopoietic stem cells in chimeric bone marrow. In addition, IL-3 may play a role in the depletion of hematopoietic stem cells in chimeric bone marrow. In the absence of IL-3, the hematopoietic stem cells may remain in a quiescent state and proliferation can be induced by stimuli, including secondary transplantation or cell passage.