Modality-related scalp responses after electrical stimulation of cutaneous and muscular upper limb afferents in humans

To elucidate whether the selective electrical stimulation of muscle as well as cutaneous afferents evokes modality-specific responses in somatosensory evoked potentials (SEPs) recorded on the scalp of humans, we compared scalp SEPs to electrical stimuli applied to the median nerve and to the abductor pollicis brevis (APB) motor point. In three subjects, we also recorded SEPs after stimulation of the distal phalanx of the thumb, which selectively involved cutaneous afferents. Motor point and median nerve SEPs showed the same scalp distribution; moreover, very similar dipole models, showing the same dipolar time courses, explained well the SEPs after both types of stimulation. Since the non-natural stimulation of muscle afferents evokes responses also in areas specifically devoted to cutaneous input processing, it is conceivable that, in physiological conditions, muscle afferents are differentially gated in somatosensory cortex. The frontocentral N30 response was absent after purely cutaneous stimulation; by contrast, it was relatively more represented in motor point rather than in mixed nerve SEPs. These data suggest that the N30 response is specifically evoked by proprioceptive inputs.     

Clinical and MRI disease activity in multiple sclerosis are associated with reciprocal fluctuations in serum and cerebrospinal fluid levels of soluble HLA class I molecules

The goal of our study was to clarify the contribution of soluble human leukocyte antigens class I (sHLA-I) in multiple sclerosis (MS) immune dysregulation. We retrospectively evaluated by ELISA cerebrospinal fluid (CSF) and serum sHLA-I levels in 79 relapsing-remitting (RR), 26 secondary progressive (SP) and 15 primary progressive (PP) MS patients stratified according to clinical and Magnetic Resonance Imaging (MRI) evidence of disease activity. One hundred and nine patients with other inflammatory neurological disorders (OIND), 88 with noninflammatory neurological disorders (NIND) and 82 healthy donors were used as controls. An intrathecal synthesis of sHLA-I detected by a specific index was significantly more consistent in MS than in controls, with more pronounced values in MS patients with relapses and MRI enhancing brain lesions. A decrease in serum sHLA-I concentrations was observed in MS patients with demyelinating attacks, while an increase in CSF levels of sHLA-I was found in MS patients with lesional activity on MRI scans. This association between intrathecal synthesis and reciprocal fluctuations of CSF and serum levels of sHLA-I in clinically and MRI active MS seems to suggest a potential role for CSF and serum levels of sHLA-I as a sensitive marker of immune activation taking place both intrathecally and systemically in MS.     

Antioxidant agents have a different expression pattern in muscle fibers of patients with mitochondrial diseases

Respiratory chain dysfunction leads to reactive oxygen species (ROS) generation with following oxidative stress and cellular damage. A histochemical and immunohistochemical study was performed on muscle biopsies from 17 patients with mitochondrial disease [chronic progressive external ophthalmoplegia (CPEO), mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), myoclonic epilepsy with ragged red fibers (MERRF)] to evaluate the expression pattern and location of manganese superoxide dismutase (MnSOD), copper-zinc superoxide dismutase (CuZnSOD) and reduced glutathione (GSH) in skeletal muscle fibers. Our data showed that: (1) MnSOD, CuZnSOD and GSH are expressed in fibers with respiratory chain deficiency; (2) the antioxidant induction is correlated with the degree of mitochondrial proliferation, but not with clinical phenotype, patients' age, duration of disease, biochemical defects or mitochondrial DNA abnormalities. In addition, we suggest that expression of MnSOD and GSH may be considered an initial, indirect sign of respiratory chain dysfunction because it is observed in the early stages of the disease.     

Raloxifene administration in premenopausal women with uterine leiomyomas: a pilot study

This prospective randomized single-blind placebo-controlled clinical trial was carried out to evaluate the effects of raloxifene administration on uterine and leiomyoma sizes in premenopausal women. Ninety healthy premenopausal women affected by asymptomatic uterine leiomyomas were enrolled and treated with raloxifene at the doses of 60 mg/d (group A), 180 mg/d (group B), or placebo (group C). The duration of the treatment was 6 cycles of 28 d each. At entry and after three and six cycles, uterine and leiomyoma sizes were measured by transvaginal ultrasonography. The difference between uterine and leiomyoma volumes (Delta size) was calculated in all subjects. The characteristics of the menstrual cycles and the side effects of the treatments were recorded using a daily diary. The severity of the uterine bleedings was assessed using a rank scale. Throughout the study, no significant changes were observed in uterine and leiomyoma size or in Delta size among the three groups and within each group of treatment. The length and severity of uterine bleedings was not significantly different between the three groups and within each group. In conclusion, raloxifene has no significant effect on uterine and leiomyoma size or on menstrual cycle in premenopausal women.     

Carbon dioxide versus normal saline as a uterine distension medium for diagnostic vaginoscopic hysteroscopy in infertile patients: a prospective,randomized, multicenter study

OBJECTIVE: To evaluate the satisfaction rate, efficacy, and complication rate of carbon dioxide (CO(2)) versus normal saline as a uterine distension medium for outpatient diagnostic vaginoscopic hysteroscopy in infertile patients. DESIGN: Prospective, randomized multicenter study. SETTING: Hysteroscopy units in two university hospitals and in a private center. PATIENT(S): One hundred eighty-nine infertile women undergoing outpatient hysteroscopy. INTERVENTION(S): Outpatient hysteroscopy was performed with CO(2) (group A) or normal saline (group B) and with endometrial biopsy when indicated. MAIN OUTCOME MEASURE(S): Quality of the visualization of the uterine cavity, procedure time, complications, patient discomfort, and satisfaction rate. RESULT(S): Significantly lower abdominal and shoulder tip pain and a lower incidence of vasovagal reactions were observed in group B in comparison with group A. A higher satisfaction rate and a lower operative time were obtained in the normal saline group in comparison with the CO(2) group. Moreover, group A required significantly more analgesics after the procedure than group B. CONCLUSION(S): Uterine distension with normal saline seems to have less adverse effects and is better tolerated by patients. Moreover, it allows operative procedures to be performed with the new bipolar instruments.     

P-glycoprotein and BCL-2 levels predict outcome in adult acute lymphoblastic leukaemia

Concurrent resistance mechanisms, such as P-glycoprotein (PGP) and bcl-2, may contribute to a worse outcome in adult acute lymphoblastic leukaemia (ALL). Between 1990 and 2000, we analysed PGP and bcl-2 by flow cytometry, using two anti-PGP (C219 and JSB-1) monoclonal antibodies (mAbs) and an anti-bcl-2 mAb in 115 de novo adult ALL patients. Both a longer overall survival (OS) and longer disease-free survival (DFS) were observed in PGP-negative patients (23%vs 0% at 3 years, P = 0.011 and 29%vs 0% at 2 years, P = 0.006 for C219 respectively; 42%vs 0% at 1.5 years, P = 0.004 and 53%vs 0% at 8.5 months, P = 0.00006 for JSB-1 respectively). Bcl-2 positivity was associated with a significantly higher complete remission rate (90%vs 66%, P = 0.01). Moreover, in 69 patients not presenting with either t(9;22) or B-mature immunophenotype, PGP negativity (JSB-1) maintained its significant favourable prognostic impact with regard to OS (41%vs 0% at 1.5 years, P = 0.009) and DFS (83%vs 0% at 6 months, P = 0.0005). Importantly, within a subset of 62 patients with normal (n = 31) or unknown (n = 31) karyotype, PGP (JSB-1)-negative patients showed both a significantly longer OS and DFS (63%vs 0% at 1.4 years, P = 0.018 and 84%vs 0% at 6 months, P = 0.001 respectively). In multivariate analysis, JSB-1 (P = 0.008) and cytogenetics (P = 0.02) were found to be independent prognostic factors with regard to DFS. Therefore, in adult ALL, PGP and bcl-2 represent sensitive indicators of clinical outcome, and potential targets of novel molecules aimed at overcoming chemoresistance and recurrent relapses.     

Microtransplantation of membranes from cultured cells to Xenopus oocytes: a method to study neurotransmitter receptors embedded in native lipids

The Xenopus oocyte is used as a convenient cell expression system to study the structure and function of heterogenic transmitter receptors and ion channels. Recently, we introduced a method to microtransplant already assembled neurotransmitter receptors from the human brain to the plasma membrane of Xenopus oocytes. The same approach was used here to transplant neurotransmitter receptors expressed from cultured cells to the oocytes. Membrane vesicles prepared from a human embryonic kidney cell line (HEK293) stably expressing the rat glutamate receptor 1 were injected into oocytes, and, within a few hours, the oocyte plasma membrane acquired alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type glutamate receptors, which had the same properties as those expressed in the original HEK cells. Analogously, oocytes injected with membranes prepared from rat pituitary GH(4)C1 cells, stably expressing homomeric human neuronal alpha 7 nicotinic acetylcholine receptors (alpha 7-AcChoRs), incorporated in their plasma membrane AcChoRs that behaved as those expressed in GH(4)C1 cells. Similar results were obtained with HEK cells stably expressing heteromeric human neuronal alpha 4 beta 2-AcChoRs. All this makes the Xenopus oocyte a powerful tool for detailed investigations of receptors and other proteins expressed in the membrane of cultured cells.     

Thrombospondin 1, a mediator of the antiangiogenic effects of low-dose metronomic chemotherapy

Chemotherapeutic drugs chronically administered to tumor-bearing mice, using a frequent schedule at doses substantially lower than the maximum tolerated dose (MTD) (i.e., metronomic dosing), can cause sustained and potent antiangiogenic effects by targeting the endothelial cells of newly growing tumor blood vessels. These effects appear to occur in the absence of an increase in the severity of side effects caused by destruction of other cell types normally sensitive to MTD chemotherapy, suggesting a marked and selective sensitivity of activated endothelial cells, the basis of which is unknown. Here we report that protracted exposure of endothelial cells in vitro to low concentrations of several different anticancer agents, including microtubule inhibitors and an alkylating agent, caused marked induction of gene and protein expression of TSP-1, a potent and endothelial-specific inhibitor of angiogenesis. Increases in circulating TSP-1 were also detected in the plasma of human tumor-bearing severe combined immunodeficient mice treated with metronomic low-dose cyclophosphamide. Most importantly, the antiangiogenic and antitumor effects of low-dose continuous cyclophosphamide were lost in TSP-1-null C57BL/6 mice, whereas, in contrast, these effects were retained by using a MTD schedule of the same drug. Taken together, the results implicate TSP-1 as a secondary mediator of the antiangiogenic effects of at least some low-dose metronomic chemotherapy regimens.