Brain activation during smooth-pursuit eye movements

A potential application of studying eye movements with functional MRI (fMRI) is to examine patient populations with known eye movement dysfunction, but the reliability with which normal subjects demonstrate activity in specific brain regions has not been established. To date, fMRI studies of smooth-pursuit eye movements have used relatively small numbers of subjects and have been restricted to fixed-effects analyses. We extend these studies to whole brain imaging at 1.5 T, properly accounting for intersubject variation using random effects analysis. Smooth-pursuit eye movements elicited activation consistently in dorsal cortical eye fields and cerebellum. Subcortical activation was greatly attenuated, but not eliminated, with the random-effects second-level analysis. In addition, session-dependent changes in activation were greater in some regions than others and may indicate areas of brain, such as the supplementary eye fields, that are sensitive to attentional modulation of eye movements.     

Pulsatile uptake of CO in the human lung

The instantaneous uptake of CO in the lungs was measured with a water-filled body plethysmograph in normal man. First, control measurements of plethysmograph pressure were made while the subject held his breath for 7 sec after breathing gas mixtures prepared to bring his alveolar P(O2) and P(CO2) close to mixed venous levels. Then, CO uptake measurements were made while he held his breath after inhaling the same gas mixtures with added CO (2.0%). The change in lung volume on CO minus the change in lung volume during the control measurement was a measure of the CO uptake in the lungs. Cardiopneumatic changes in lung gas volume were subtracted electrically. All of five subjects showed pulsatile CO uptake. The mean CO uptake was 103 ml/min. A peak uptake of 2.0 (range 1.6-2.3) times the mean uptake occurred 0.3-0.4 sec after the R wave of the EKG and a minimum uptake of 0.4 (range 0.2-0.5) times the mean uptake occurred during the tenth of a second before the R wave of the EKG. These results suggest that pulmonary capillary blood volume is pulsatile during the cardiac cycle.     

Comparison of plain ice and flavoured ice for preventing oral mucositis associated with the use of 5 fluorouracil

Aims and objectives. The study aimed to compare the use of plain ice, flavoured ice and standard care, to evaluate the effect on mucositis and to determine patients’ perceptions of the two forms of oral cryotherapy. Background. Despite evidence that oral cryotherapy is useful in preventing mucositis in patients receiving 5‐fluorouracil, concerns have been expressed about its clinical utility, due to potential side effects and negative perceptions. Design. A randomized, controlled, crossover trial was conducted in the outpatient chemotherapy department of an acute care teaching hospital in Perth, Western Australia. Patients were randomized to receive each of three interventions across three cycles of chemotherapy: standard care alone; standard care plus plain ice; and standard care plus flavoured ice. Methods. Oral mucositis was assessed by nurses prior to each of the three chemotherapy cycles and 15 days after each intervention. Two assessment tools were used, the Oral Assessment Guide, and the Western Consortium Cancer Nursing Research Scale. Participants completed a questionnaire to determine their comfort and satisfaction with oral cryotherapy, as well as factors affecting compliance. Results. Findings from 67 patients revealed that when participants used standard care alone, they were significantly more likely to experience symptoms of mucositis than when they used either plain or flavoured ice. Odds ratios were at least threefold higher for standard care alone, varying according to the instrument used. The two main concerns reported were the taste of flavoured ice and the time required to complete the cryotherapy interventions. Side effects such as nausea, sensitivity and headache were reported more frequently for flavoured ice (n = 11) compared with plain ice (n = 5) and standard care (n = 1). Conclusions. Both forms of oral cryotherapy were effective in reducing the severity of oral mucositis after chemotherapy and were more effective than standard care alone. Flavoured ice was associated with the highest frequency of side effects. Relevance to clinical practice. The benefits of cryotherapy appear to outweigh the problems in this sample of patients. The intervention should be tailored to individual patients, based on preferences for plain versus flavoured ice and small chips vs. larger blocks. Unsweetened frozen fruit juices should be evaluated. Time constraints could be addressed by providing transportable containers of ice.     

Persistence of Plasmodium falciparum in the placenta after apparently effective quinidine/clindamycin therapy.

The persistence of Plasmodium falciparum in the placenta after apparently adequate therapy with quinine has been described. We describe this phenomenon in the placenta of a 19-year-old woman with falciparum malaria, who was treated with a combination of quinidine and clindamycin. Although this therapy was effective and diminished her peripheral blood parasitemia from 3% at presentation to almost undetectable at the time of delivery, vast numbers of P. falciparum-infected erythrocytes were present in the maternal sinusoids of the placenta. This sequestration of infected erythrocytes produced a local parasitemia in the placenta of 70% to 80%. Additionally, rare Plasmodium-infected erythrocytes were also seen in the fetal blood of the placenta. We review malaria in pregnancy, parasitic involvement of the placenta and emphasize that Plasmodium-infected erythrocytes may persist in the placenta even after clearance of parasites from the peripheral blood.     

Critical appraisal workshops to promote evidence-based healthcare.

We evaluated the effect of literature appraisal workshops on participants views, attitudes and knowledge about evidence-based medicine in the West Midlands region in 1998. The performance of 55 practitioners was evaluated, before and after attending the workshop. After attending the workshop, participants paid more attention to the study design (81% vs. 98%, P=0.02), they did not find research evidence confusing (35% vs. 52%, P=0.05), and they felt more confident in assessing research evidence (26% vs. 59%, P=0.0001). Their mean knowledge scores improved from 47.3 (SD12.2) to 57.9 (SD 9.0) ( P=0.0001). Our critical appraisal skills workshops improved attitudes and knowledge needed for the provision of evidence-supported healthcare. Such workshops should be incorporated in postgraduate obstetrics and gynaecology training programmes.     

Determination of vocal fold mucosal wave velocity in an in vivo canine model

The vocal fold traveling wave is essential to normal voice production. The present investigation examined whether the velocity of the traveling wave (TWV) could be consistently determined in an in vivo canine model and if traveling wave velocity is affected by changes in the amplitude of recurrent laryngeal nerve stimulation (RLNS) and superior laryngeal nerve stimulation (SLNS). The results showed that traveling wave velocity increased with an increase in recurrent laryngeal nerve stimulation at low constant superior laryngeal nerve stimulation, but was poorly correlated with increases in recurrent laryngeal nerve stimulation at a high level of superior laryngeal nerve stimulation. Furthermore, traveling wave velocity was significantly correlated with superior laryngeal nerve stimulation at constant recurrent laryngeal nerve stimulation. This study demonstrated the feasibility of objectively measuring traveling wave velocity in vivo.     

Cervical Positioning for Reduction of Sleep-Disordered Breathing in Mild-to-Moderate OSAS

The objective of this study was to assess whether cervical positioning could improve mild to moderate cases of the obstructive sleep apnea syndrome (OSAS). Eighteen subjects recruited from a tertiary sleep disorders clinic population with mild to moderate cases of OSAS were evaluated using a custom-fitted cervical pillow designed to increase upper airway caliber by promoting head extension. The subjects used their usual pillows during two consecutive recorded baseline nights in our laboratory. They then used the cervical pillow for 5 days at home and returned for 2 consecutive recorded nights at our laboratory to use the cervical pillow. During the nights in our laboratory, the subjects completed questionnaires, were videotaped to record head and body position, and had full polysomnography. The subjects had a significant trend toward improvement in their respiratory disturbance indices with use of the cervical pillow, despite spending more time in the supine position and having similar amounts of REM sleep in the baseline and experimental conditions. They also had nonsignificant trends toward improvements in their sleep efficiency and subjective depth of their sleep as well as significantly fewer arousals and awakenings in the experimental compared with the baseline condition. We propose that cervical positioning (i.e., head extension) with a custom-fitted cervical pillow provides a simple, noninvasive, and comfortable means of reducing sleep-disordered breathing in patients with mild to moderate OSAS.     

Complete, circular papovavirus genomes in the cells of hamsters exposed to a horizontally transmitted lymphomagenic agent

Contagious lymphomas were produced in a colony of Syrian golden hamsters by an unknown agent that also caused fatal ulcerative bowel disease (UBD) lesions prior to lymphoma development. A low percentage of these animals developed epitheliomas of the skin independently of the UBD or lymphomas. Previous work has shown that the epitheliomas contain numerous hamster papovavirus (HaPV) particles, whereas lymphomas do not. Cells from both kinds of tumors do contain HaPV DNA sequences, however. In this study, Southern blot hybridization showed that complete, circular HaPV genomes were present in these cells. Complete, circular HaPV genomes also were found in the cells of animals with UBD. Electron microscopy revealed the presence of HaPV particles in UBD lesions. These results, together with previous data, indicate that in the hamster, lymphomas contain complete, circular papovavirus genomes in the absence of virus particles, whereas epitheliomas and UBD lesions contain these genomes in the presence of virus particles.     

Oligoclonal bands predict multiple sclerosis in children with optic neuritis

We retrospectively evaluated predictors of conversion to multiple sclerosis (MS) in 357 children with isolated optic neuritis (ON) as a first demyelinating event who had a median follow‐up of 4.0 years. Multiple Cox proportional‐hazards regressions revealed abnormal cranial magnet resonance imaging (cMRI; hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 3.39–10.39, p < 0.001), presence of cerebrospinal fluid immunoglobulin G oligoclonal bands (OCB; HR = 3.69, 95% CI = 2.32–5.86, p < 0.001), and age (HR = 1.08 per year of age, 95% CI = 1.02–1.13, p = 0.003) as independent predictors of conversion, whereas sex and laterality (unilateral vs bilateral) had no influence. Combined cMRI and OCB positivity indicated a 26.84‐fold higher HR for developing MS compared to double negativity (95% CI = 12.26−58.74, p < 0.001). Accordingly, cerebrospinal fluid analysis may supplement cMRI to determine the risk of MS in children with isolated ON. Ann Neurol 2015;77:1076–1082