Respiratory virus infections in transplant recipients after reduced-intensity conditioning with Campath-1H: high incidence but low mortality

Respiratory virus infections can cause serious morbidity and mortality after conventional allogeneic stem cell transplantation. However, the incidence and outcome of these infections after reduced intensity conditioning has not been reported. Between 1997 and 2001, 35 episodes of respiratory virus infections were noted in 25 of 83 transplant recipients conditioned with fludarabine, melphalan and Campath-1H, and 80% of them received early antiviral therapy. Parainfluenza virus (PIV) 3 was the commonest isolate (45.7%) followed by respiratory syncytial virus (37%). Patients with myeloma were more susceptible to these infections [odds ratio (OR) 4.1, P = 0.01] which were often recurrent in patients with severe acute or chronic graft-versus-host disease (GVHD) (OR 10.6, P = 0.03). Infection within the first 100 d (OR 5.0, P = 0.05) and PIV 3 (OR 9.2, P = 0.01) isolation were risk factors for developing lower respiratory infection. Although more than half of the episodes progressed to lower respiratory infection, the mortality was only 8%. This could have been due to early initiation of antiviral therapy, but the attenuation of pulmonary damage due to the reduced-intensity conditioning, low incidence of GVHD and, paradoxically, the low CD4+ T-cell subset in this setting might also have been contributory factors.     

Development of rapid,sensitive one-tube duplex RT-PCR assay for specific and differential diagnosis of Chikungunya and dengue

Chikungunya and dengue, two arboviral infections are common in South-East Asia and their early clinical manifestations are very similar hence it is important to discriminate between them as early as possible for better clinical management. The aim of this study was to design a rapid, sensitive and specific method for the differential diagnosis of these two viruses simultaneously. A rapid one-tube duplex RT-PCR assay was developed that requires 110 min including RNA extraction, RT-PCR and agarose gel electrophoresis by using a novel Taq polymerase with high processivity. This one-tube duplex RT-PCR system with primers designed from the conserved regions of the genome allowed discrimination between the two viral groups. Bioinformatics analysis of the DNA sequences from PCR amplified products confirmed that this method was very specific and accurate. The time required for this duplex RT-PCR was comparable to the standard IgM capture ELISA method. This novel approach would help to diagnose specifically and accurately these two closely related arboviruses and enable early detection from blood. This method could be applied in resource limited settings, for surveillance in endemic regions or for routine epidemiological screening.     

Liquid‐Crystalline Nano‐optomechanical Actuator

The synthesis and characterization of organic nanoparticles composed of a polymer network of azobenzene moieties and capable of reproducible, photoinduced mechanical actuation are reported. The molecules within the nanoparticles undergo co‐ordinated, reversible isomerization between cis‐ and trans‐conformations in response to ultraviolet and visible electromagnetic radiation, resulting in a reversible 20% height contraction of nanoparticles adsorbed on a substrate. The kinetics of the actuation response as a function of light intensity and duration are reported and closely match the molecular kinetics of azobenzene photoisomerization. The results support the proposed mechanism of co‐ordinated molecular conformational changes resulting in observable nanoscale actuation.     

Oxytocin increases eye contact during a real-time,naturalistic social interaction in males with and without autism

Autism spectrum conditions (autism) affect ~1% of the population and are characterized by deficits in social communication. Oxytocin has been widely reported to affect social-communicative function and its neural underpinnings. Here we report the first evidence that intranasal oxytocin administration improves a core problem that individuals with autism have in using eye contact appropriately in real-world social settings. A randomized double-blind, placebo-controlled, within-subjects design is used to examine how intranasal administration of 24 IU of oxytocin affects gaze behavior for 32 adult males with autism and 34 controls in a real-time interaction with a researcher. This interactive paradigm bypasses many of the limitations encountered with conventional static or computer-based stimuli. Eye movements are recorded using eye tracking, providing an objective measurement of looking patterns. The measure is shown to be sensitive to the reduced eye contact commonly reported in autism, with the autism group spending less time looking to the eye region of the face than controls. Oxytocin administration selectively enhanced gaze to the eyes in both the autism and control groups (transformed mean eye-fixation difference per second=0.082; 95% CI:0.025–0.14, P=0.006). Within the autism group, oxytocin has the most effect on fixation duration in individuals with impaired levels of eye contact at baseline (Cohen''s d=0.86). These findings demonstrate that the potential benefits of oxytocin in autism extend to a real-time interaction, providing evidence of a therapeutic effect in a key aspect of social communication.     

Effects of heparin and protamine on left ventricular performance in the dog.

The effects of protamine on left ventricular (LV) function were measured under conditions of controlled heart rate and proximal aortic pressure in eight anaesthetized, heparinised dogs. Protamine 3 mg.kg-1 produced a 21% decrease in LV dP/dt max, a 43% decrease in cardiac output, a 47% decrease in stroke work and decreases in systolic and diastolic pressures (-16%, -19% respectively). Protamine 6 mg.kg-1 resulted in a 17% decrease in LV dP/dt max, a 26% decrease in cardiac output, a 50% decrease in LV stroke work and 25 and 30% decreases in systolic and diastolic pressures. These results show that an impairment of LV function plays an important part in the circulatory depression produced by protamine.