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Intracortical microstimulation (ICMS) delivered to the motor cortex (M1) via long- or short-train duration (long- or short-duration ICMS) can evoke coordinated complex movements or muscle twitches, respectively. The role of subcortical cerebellar input in M1 output, in terms of long- and short-duration ICMS-evoked movement and motor skill performance, was evaluated in rats with bilateral lesion of the deep cerebellar nuclei. After the lesion, distal forelimb movements were seldom observed, and almost 30% of proximal forelimb movements failed to match criteria defining the movement class observed under control conditions. The classifiable movements could be evoked in different cortical regions with respect to control and many kinematic variables were strongly affected. Furthermore, movement endpoints within the rat's workspace shrunk closer to the body, while performance in the reaching/grasping task worsened. Surprisingly, neither the threshold current values for evoking movements nor the overall size of forelimb movement representation changed with respect to controls in either long- or short-duration ICMS. We therefore conclude that cerebellar input via the motor thalamus is crucial for expressing the basic functional features of the motor cortex., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Electrical stimulation of the motor cortex in the rat can evoke complex forelimb multi-joint movements, including movement of limb and paw. In this study, these movements have been quantified in terms of 3D displacement and kinematic variables of two markers positioned on the wrist and middle digits (limb and paw movement, respectively). Electrical microstimulation was applied to the motor cortex using a pulse train of 500 ms duration. Movements were measured using a high-resolution 3D optical system. Five classes of limb movements (abduction, adduction, extension, retraction, elevation) and four classes of paw movements (opening, closure, opening/closure sequence, supination) were described according to their kinematics. A consistent topography of these classes of movements was presented across the motor cortex together with a topography of spatial locations to which the paw was directed. In about one-half of cortical sites, a specific pattern of limb-paw movement combination did exist. Four categories of limb-paw movements resembling behavioral repertoire were identified: reach-shaping, reach-grasp sequence, bring-to-body, and hold-like movement. Overall, the forelimb motor region included: (1) a large caudal forelimb area dominated by reach-shaping movement representation; (2) a small rostral area containing reach-grasp sequence and bring-to-body movement representation; and (3) a more lateral portion where hold-like movement was represented. These results support the view that, in rats, the motor cortex controls forelimb movements at a relatively complex level and suggest that the orderly representation of complex movements and their dynamics/kinematics emerge from the principles of forelimb motor cortex organization.

Game parks in Tanzania have long been considered to be at low risk for African trypanosomiasis; however, nine cases of the disease associated with these parks were recently reported. The outbreak was detected through TropNetEurop, a sentinel surveillance network of clinical sites throughout Europe.

The aim of this study was to characterize a Bartonella strain (BA-1) isolated from a blood culture of an Italian, human immunodeficiency virus-positive patient with bacillary angiomatosis. We analyzed the isolate using molecular biology methods such as whole-cell fatty acid analysis, PCR-restriction fragment length polymorphism analysis, type-specific 16S rRNA PCRs, sequence analysis of the 16S rRNA, pulsed-field gel electrophoresis, and arbitrarily primed PCR. The BA-1 isolate turned out to be a Bartonella quintana strain, similar but not identical to B. quintana Oklahoma, which was used as a control strain.

A cluster of hepatitis C virus (HCV) infections among gynecological patients who underwent surgical intervention in the same setting is described. An epidemiological investigation was conducted to identify the cases, the likely source of infection, and the route of transmission. Four recent HCV infections were identified. Based on molecular fingerprinting analysis and epidemiological investigation, transmission between the putative source patient (an HCV-positive woman who was the first patient of the surgical session) and outbreak patients was highly suggestive. All patients, including the source patient, were infected with HCV type 1b. Molecular characterization of HCV clones by sequence analysis of both structural envelope regions (20 clones from the source patient and 58 from the outbreak patients) and the nonstructural NS5 region of the viral genome (12 clones from the source patient and 32 from the outbreak patients) showed close homology between the viral isolates from the source and those from the outbreak patients that was higher than that observed between the viral isolates from the source and those from four unrelated, HCV type 1b-infected patients from the same geographical area (in the latter case, 33 clones were sequenced for the envelope regions and 30 were sequenced for the NS5 region). The mean percent divergence between clones was 4.69 for the envelope and 3.71 for the NS5 region in the source patient and the outbreak patients compared with 6.76 (P = 0.001) and 5.22 (P = 0.01) in the source patient and control patients, respectively. Among the risk factors investigated, only that of having undergone surgery in the morning session of the same day reached statistical significance (P = 0.003). The investigation showed that the source patient and outbreak patients shared only the administration of propofol in multidose vials. The study documents the risk of nosocomial transmission of HCV and the importance of infection control procedures in the operating room and highlights the crucial role of molecular strategies, especially sequence-based phylogenetic analysis of cloned viral isolates, in the investigation of HCV outbreaks.

A multicenter open, randomized, controlled trial was conducted to determine whether primary prophylaxis for Pneumocystis carinii pneumonia and toxoplasmic encephalitis can be discontinued in patients infected with human immunodeficiency virus type 1 (HIV-1) whose CD4+ T cell counts have increased to >200 cells/mm3 (and who have remained at this level for at least 3 months) as a result of highly active antiretroviral therapy (HAART). Patients were randomized to either the discontinuation arm (i.e., those who discontinued prophylaxis; n=355) or to the continuation arm (n=353); the 2 arms of the study were similar in terms of demographic, clinical, and immunovirologic characteristics. During the median follow-ups of 6.4 months (discontinuation arm) and 6.1 months (continuation arm) and with a total of 419 patient-years, no patient developed P. carinii pneumonia or toxoplasmic encephalitis. The results of this study strongly indicate that primary prophylaxis for P. carinii pneumonia and toxoplasmic encephalitis can be safely discontinued in patients whose CD4+ T cell counts increase to >200 cells/mm3 during HAART.

Serum samples from 66 seropositive subjects (56 with a history of intravenous drug abuse), including asymptomatic carriers and patients with persistent generalised lymphadenopathy (PGL), AIDS related complex (ARC), and AIDS, were tested by indirect immunofluorescence on rat tissue sections and HEp-2 cells for the presence of antibodies to nuclei, smooth muscle, intermediate filaments (anti-IMF) and microfilaments (anti-MF). Counterimmunoelectrophoresis was also used to detect antibodies to extractable nuclear antigens. Smooth muscle antibodies with the V pattern or antinuclear antibodies, mainly of the speckled type, or anti-IMF, occurred in 35 cases, being widely distributed in all groups. Such an autoantibody response resembles the "viral" autoimmunity described in various infectious diseases and in particular that of non-A, non-B post-transfusion hepatitis. Autoantibodies may be of some prognostic relevance, as the prevalence of smooth muscle antibodies V increased as the disease progressed (asymptomatic carriers 20%, those with PGL 29%, those with ARC 47%, and those with AIDS 63%. In the PGL group autoantibody positivity correlated with the presence of skin anergy. The fact that autoantibodies were more frequently detected in patients with circulating immune complexes suggests that these can contain autoantibodies and the corresponding autoantigens.