Brain processing of native and foreign languages.

We used positron emission tomography to study brain activity in adults while they were listening to stories in their native language, in a second language acquired after the age of seven, and in a third unknown language. Several areas, similar to those previously observed in monolinguals, were activated by the native but not by the second language. Both the second and the unknown language yielded distinct left-hemispheric activations in areas specialized for phonological processing, which were not engaged by a backward speech control task.

Basal ganglia and thalamo-cortical hypermetabolism in patients with spasmodic torticollis.

Unlabelled: The basal ganglia are thought to be involved in the primary dystonias, largely because of the repeated demonstration of neuropathological changes in these nuclei in the secondary dystonias. A hyperactivity of a network involving basal ganglia has been suggested in experimental animal dystonia. To test this hypothesis in humans, we studied the functional correlates of primary cervical dystonia using [18F]FDG and PET.

Dementia of the frontal lobe type: report of the neuroimaging and neuropsychological results of a case study.

We report the behavioural abnormalities, neuroimaging, and neuropsychological results of a 62-year-old patient, i.p., who shows a clinical profile that fulfils all characteristics of dementia of frontal lobe type.

Mycobacterium avium complex infection in mice: lack of exacerbation after LP-BM5 murine leukemia virus infection.

The murine leukemia virus LP-BM5 has been used to reproduce the model of murine AIDS in order to evaluate the course of infection with the MO-1 strain of Mycobacterium avium complex (MAC). LP-BM5 was inoculated in C57BL/6 mice by intravenous (i.v.

Persistent post-traumatic retrograde amnesia: a neuropsychological and (18F)FDG PET study.

We report the case of a 48-year old woman who, after a severe closed head injury, developed a severe and persistent disruption of retrograde memory, associated with a mild impairment of learning abilities. The patient's dense amnesia spared only the childhood period and included both explicit memory (autobiographical and semantic) and procedural skills. Because of her partially spared learning ability and intact language, intensive training by family members resulted in the reacquisition and retention of many autobiographical events and of some skills she had lost after the accident.

Tibial component in total knee arthroplasty: To cement or not to cement?

Loosening of the tibial component is a major cause of failure in total knee arthroplasty. Implant stability is a key element for achieving long term successful results and relies on the interplay of several factors which include the method of fixation, prosthesis design, surgical technique, bone quality and patient characteristics.The analysis of these aspects may provide some guidelines for the choice of fixation, but an ultimate solution of the problem can not be found in the past experience with total knee replacement.

An elastic computerized brain atlas for the analysis of clinical PET/SPET data.

An elastic computerized brain atlas was developed for the analysis of positron emission tomography/single-photon emission tomography (PET/SPET) data. It consists of a set of digital anatomical contours and a template of regions of interest, schematically describing the brain, derived from a currently used anatomical/functional brain atlas. A warping algorithm, matching equivalent contours, was implemented to elastically fit the atlas to individual brain images.

The desensitization of the embryonic mouse muscle acetylcholine receptor depends on the cellular environment.

The rate of desensitization of nicotinic acetylcholine (ACh) receptor (nAChR), an important characteristic of nAChR function, was studied in myotubes of the mouse C2C12 cell line at different times after fusion, by measuring the decay of ACh-evoked currents (IACh) under various patch-clamp configurations. We observed a progressive slowing of IACh decay rate (half-decay time rose from about 0.5 s to over 5 s) in myotubes of increasing size (i.

Acetylcholine-activated inward current induces cytosolic Ca2+ mobilization in mouse C2C12 myotubes.

We examined the spatiotemporal pattern of intracellular Ca2+ liberation in mouse myotubes by means of fluorescence imaging of cytosolic free Ca2+ together with the simultaneous recording of membrane whole-cell currents. Acetylcholine (ACh) applications to C2C12 myotubes equilibrated in Ca(2+)-free medium and voltage clamped at -50 mV evoked localized fluorescence transients of variable amplitude with less than 0.5 s delay.

Cefodizime modulates in vitro tumor necrosis factor-alpha, interleukin-6 and interleukin-8 release from human peripheral monocytes.

Among third-generation cephalosporins, cefodizime (CFDZ) has shown to modulate many functions of the host defense system against infections. The aim of the present study was to assess the in vitro CFDZ-dependent modulation of interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and IL-8 release from lipopolysaccharide (LPS)-stimulated human peripheral mononuclear cells (MNCs). Two other third-generation cephalosporins: ceftriaxone (CFX) and ceftazidime (CFT), were also tested under the same experimental conditions.

Protein kinase C modulates exogenous acetylcholine current in Xenopus oocytes.

The modulation of acetylcholine-activated current (IACh) by protein kinase C (PKC) was studied in Xenopus laevis oocytes microinjected with either mRNA extracted from C2C12 myotubes (C2C12 mRNA) or RNAs encoding murine alpha beta gamma delta subunits of the nicotinic ACh receptor (nAChR). Voltage-clamped oocytes were treated for 90 sec with 12-O-tetradecanoylphorbol-13-acetate (TPA, 300 nM), a potent PKC activator. Transient increase in the amplitude and acceleration in the decay of IACh were invariably observed within minutes of TPA application, and were independent of extracellular Ca2+ concentration.

Two forms of acetylcholine receptor gamma subunit in mouse muscle.

Nicotinic acetylcholine receptors (nAcChoRs) of skeletal muscle are heterosubunit ligand-gated channels that mediate signal transmission from motor nerves to muscle. While cloning murine nAcChoR subunits, to gain an insight into the receptor diversity across species, we detected two forms of gamma subunits in the myogenic C2C12 cell line. Both forms are functional when expressed in Xenopus oocytes.

Clinical/metabolic correlations in multiple system atrophy. A fludeoxyglucose F 18 positron emission tomographic study.

Objective: To evaluate the regional cerebral metabolic involvement; the relationships among regional brain metabolism, clinical features, and quantitative measures of disease severity; and the patterns of brain involvement that can be related to the different types of onset: striatonigral degeneration vs olivopontocerebellar atrophy.

Design: Fludeoxyglucose F 18 positron emission tomography (PET) studies performed in patients with multiple system atrophy (MSA) were evaluated for their clinical features at the onset of the disease and at the time of the PET study.

Cases: Seventeen patients diagnosed as having probable MSA and 10 age-matched controls.

[18F]FDG PET study in obsessive-compulsive disorder. A clinical/metabolic correlation study after treatment.

Background: We used [18F]FDG and PET in patients with obsessive-compulsive disorder (OCD) to evaluate cerebral metabolic involvement before and after treatment with serotonin-specific reuptake inhibitors.

Method: In 11 untreated, drug-free adults, regional cerebral metabolic rate for glucose (rCMRglu) was compared with that of 15 age-matched normal controls.

Results: rCMRglu values were significantly increased in the cingulate cortex, thalamus and pallidum/putamen complex.

Correlations between cognitive impairment, middle cerebral artery flow velocity and cortical glucose metabolism in the early phase of Alzheimer's disease.

In a previous transcranial Doppler (TCD) study, we demonstrated a decrease in blood flow velocity in the proximal tract of the middle cerebral artery (MCA) in patients with Alzheimer's disease (AD). In these patients there was also an asymmetry in blood flow velocity which positively correlated with the cognitive asymmetry often seen in the early phase of AD. In this study we found a correlation between the absolute values and asymmetry indexes of MCA blood flow velocity with adjusted metabolic values and asymmetry indexes of the relative cortical frontotemporoparietal (FTP) areas, evaluated by FDG-PET, and with neuropsychological asymmetry indexes.

TNF-alpha increases the frequency of spontaneous miniature synaptic currents in cultured rat hippocampal neurons.

Tumor necrosis factor-alpha (TNF-alpha) is a cytokine secreted by activated astrocytes and is known to alter evoked synaptic activity in slices of adult rat hippocampus. In this paper we show that TNF-alpha increases the frequency of spontaneous miniature synaptic currents in cultured hippocampal neurons, acting at nanomolar concentrations. In addition, we show that the mRNA for the 55 kDa TNF-alpha receptor (TNF-R1) is detected in embryonic rat hippocampal cultures, as well as in acutely dissected embryonic and adult rat hippocampi.

Ca2+ signalling pathways activated by acetylcholine in mouse C2C12 myotubes.

In mouse C2C12 myotubes acetylcholine (ACh) elevates the concentration of myoplasmic Ca2+ ([Ca2+]i) by inducing Ca2+ influx through transmitter-gated and voltage-gated channels, and by mobilizing Ca2+ from internal stores. The relative contribution of each of these ACh-activated sources to the global [Ca2+]i elevation was estimated. We found that Ca2+ entry through voltage- and ACh-gated channels accounts for roughly 80% of the total [Ca2+]i increment, while mobilization from internal caffeine-sensitive and inositoltrisphosphate- (InsP3-) sensitive stores contributes the remaining 20% to the maximal [Ca2+]i increment.

Cognitive impairment in Duchenne muscular dystrophy.

Cognitive function and dystrophin gene mutations were investigated in 50 DMD patients (mean age 11.1 yr; range 3.5-20.

Early degenerate selection of thymocytes by class I major histocompatibility complex.

Ontogeny of T cells is accomplished in the thymus by a process of positive selection, in which interaction of the T cell receptor (TcR) expressed on CD4+8+ thymocytes with self major histocompatibility complex (MHC), expressed on cortical epithelial cells, determines the progress along the maturation pathway and confers self restriction to T cells. Conversely, cells behaving as self reactive by interaction with bone marrow-derived antigen-presenting cells are negatively selected by apoptosis. We show here that the presence of a class I-restricted soluble TcR (sTcR) in the fetal thymic microenvironment, early in T cell ontogeny, determines an enhanced negative selection of a sizeable number of CD4+8+ thymocytes, which have been previously subjected to a positive-selection event.

High-resolution technetium-99m-HMPAO SPECT in patients with probable Alzheimer's disease: comparison with fluorine-18-FDG PET.

Unlabelled: SPECT studies of regional cerebral perfusion with a high-resolution system were compared to PET studies of regional cerebral glucose utilization (rCMRglc) in 21 patients with probable Alzheimer's disease (AD). Ten normal subjects were also evaluated with SPECT and 10 with PET.

Methods: rCMRglc (for PET) and counts (for SPECT) in the associative cortices were normalized to the average rCMRglc, and counts in the calcarine cortex and basal ganglia were considered as a "reference area" to obtain a ratio.

Spondylosis and lumbar instability: pathologic changes.

The degenerative processes of the lumbar spine generally initiate from the intervertebral disc, at the level of which progressive biochemical and structural changes take place leading to a modification in its physical properties of elasticity and mechanical resistance. Disc lesions cause pathological changes in the vertebral bodies, where osteophytes appear, and in the posterior joints. In more severe forms of the process the severe deformation of joint shape may lead to a condition of spondylolisthesis.

High concentration of peripheral blood mononuclear cells harboring infectious virus correlates with rapid progression of human immunodeficiency virus type 1-related diseases.

In a cohort of 103 asymptomatic seropositive subjects (Centers for Disease Control and Prevention [CDC] stage II/III) followed for 2 years, the concentration of peripheral blood mononuclear cells harboring infectious human immunodeficiency virus (HIV) type 1 (viral burden) was correlated with the rate of decrease of CD4 cell count (RD-CD4; R = .857). Rapidly progressing patients (RD-CD4 > or = 60%; n = 18) had a high viral burden (mean +/- SE, 572 +/- 202 cells/mL) and an 89% progression to CDC IV-A-C, while stable patients (RD-CD4 < 30%; n = 55) had a low viral burden (mean +/- SE, 28 +/- 4 cells/mL) and remained asymptomatic.

The role of peripheral opioid receptor subtypes in the modulation of gastric acid secretion and plasma gastrin in dogs.

The peripheral opioid receptor subtypes involved in the regulation of gastric acid secretion were studied in dogs with both a gastric fistula and a Heidenhain pouch, by using the putative mu-opioid receptor agonist dermorphin, the delta-opioid receptor agonist [D-Ala2,D-Leu5]enkephalin (DADLE) and the kappa-opioid receptor agonist dynorphin-(1-13). Dermorphin caused a significant increase in basal acid secretion from both the gastric fistula and the Heidenhain pouch, while DADLE and dynorphin-(1-13) did not. Acid secretion stimulated by 2-deoxy-D-glucose from the gastric fistula was not modified by dermorphin and dynorphin-(1-13), while DADLE significantly inhibited it; at the same time gastric secretion from the Heidenhain pouch was significantly increased by dermorphin and unmodified by DADLE and dynorphin-(1-13).

Cholinergic responses in cloned human TE671/RD tumour cells.

The cholinergic responses of the human tumour cell line TE671/RD were examined using digital Ca2+ imaging fluorescence microscopy and patch-clamp measurements. In response to stimulation of the muscarinic acetylcholine (ACh) receptor (mAChR), the intracellular concentration of Ca2+ ([Ca2+]i) rose about two-fold, in parallel with inositol 1,4,5-trisphosphate accumulation, measured by chromatographic techniques. By contrast, there was no increment of [Ca2+]i upon stimulation of the nicotinic ACh receptor (nAChR), nor after caffeine application.