Hg concentrations in fish from coastal waters of California and Western North America.

The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3µg/gwet weight (ww), and 10 locations an average above 1.0µg/gww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds.

Treatment with mild brain hypothermia for cardiopulmonary resuscitation after myoclonic seizures in infant with robertsonian type of trisomy 13.

Congenital chromosomal abnormality with trisomy 13 is known to be associated with poor life prognosis and lethal. Therefore, physician advice the patients be kept in intensive treatment with resuscitation and state of the art intensive care when sudden change in the general condition with this trisomy is observed. We report herein, the treatment with mild brain hypothermia therapy for cardiopulmonary resuscitation after myoclonic seizures in infant with Robertsonian type of trisomy 13 in intensive care unit. Our study indicated that brain hypothermia therapy and steroid pulse therapy on an infant who was believed to have post-resuscitation hypoxic encephalopathy was highly effective as the patient's general condition recovered to the original state after four months.

Observation of the spatial distribution of gravitationally bound quantum states of ultracold neutrons and its derivation using the Wigner function.

Ultracold neutrons (UCNs) can be bound by the potential of terrestrial gravity and a reflecting mirror. The wave function of the bound state has characteristic modulations. We carried out an experiment to observe the vertical distribution of the UCNs above such a mirror at the Institut Laue-Langevin in 2011. The observed modulation is in good agreement with that prediction by quantum mechanics using the Wigner function. The spatial resolution of the detector system is estimated to be 0.7 µm. This is the first observation of gravitationally bound states of UCNs with submicron spatial resolution.

Spatial trends and impairment assessment of mercury in sport fish in the Sacramento-San Joaquin Delta watershed.

A three-year study was conducted to examine mercury in sport fish from the Sacramento-San Joaquin Delta. More than 4000 fish from 31 species were collected and analyzed for total mercury in individual muscle filets. Largemouth bass and striped bass were the most contaminated, averaging 0.40 microg/g, while redear sunfish, bluegill and rainbow trout exhibited the lowest (<0.15 microg/g) concentrations. Spatial variation in mercury was evaluated with an analysis of covariance model, which accounted for variability due to fish size and regional hydrology. Significant regional differences in mercury were apparent in size-standardized largemouth bass, with concentrations on the Cosumnes and Mokelumne rivers significantly higher than the central and western Delta. Significant prey-predator mercury correlations were also apparent, which may explain a significant proportion of the spatial variation in the watershed.

[A study on cervical reflex induced by click stimuli in cats].

UNLABELLED: The effects of click stimuli on the cervical muscle have been wildly studied, but no information is available on what reaction click stimuli elicit from the cervical cord. We studied the effects of click stimuli on the cervical cord in cats. PURPOSE: To determine the response of the cervical cord to click stimuli in cats. MATERIALS AND METHODS: Subjects were ten adult cats confirmed to have normal tympanic membranes. Cats were placed on artificial ventilation by tracheal incision. Auditory brainstem response (ABR) of both ears was measured to determine its threshold. Following the cervical incision, the dorsal vertebrae were removed, the cervical cord was exposed at C3 to C6, and bipolar needle electrodes were inserted. The reference electrode was attached to the forehead. Click stimuli were presented using 1-20 Hz clicks. RESULTS: Responses peaking at 4.89-5.10 ms were induced by click stimuli of 105 dBSPL (1 Hz) at C3. Latencies tended to be prolonged with decreasing sound pressure. No response was confirmed at of C4 to C6. The responses to clicks of 20 Hz or more disappeared when 100 responses were summed. After the experiment, we confirmed that accessory nerves showed a response to electrical stimuli applied by bipolar needle electrodes. The cervical cord was removed to make sure that the electrode had been passed into the spinal nucleus of the accessory nerve. DISCUSSION: Spinal nuclei of accessory nerves exist at C3 to C5 of the cervical cord, and are associated with the movement of the sternocleidomastoid muscle at C3 in particular. Click stimuli are reported to affect the sternocleidomastoid muscle. The results of our study appear to reflect the response of the spinal nucleus of the accessory nerve to click stimuli. The fact that responses to clicks of 20 Hz or more disappeared when 100 responses were summed suggests that the response was induced via a pathway other than the auditory pathway.

[A case of convergence spasm in hysteria improved with a brief psychiatric assessment].

We report a 16-year-old female who developed double vision. The diplopia was in the horizontal plane and persisted for 3 weeks. She also complained of headache and nausea. She kept her eyes closed unless she was told to open. When eyelids were passively open, both eyes deviated inward in an adducted position. The pupil size and the reaction to light were normal. No weakness was noted in the extraocular muscles when each eye was examined individually. The rest of the neurologic examinations were normal. We thought that she had a convergence spasm. Brain CT and MRI were normal. The CSF and blood chemistries were also normal. We treated her with supportive psychotherapy and her convergence spasm disappeared. We concluded that her convergence spasm was a manifestation of conversion hysteria.

[Effect of adrenaline on vagus nerve reflexes].

INTRODUCTION: Dizziness or syncope may occur during treatment of nasal disease. These symptoms are considered imputable to the vagovagal reflex, which is partly involved in neurogenic syncope. In response to trigeminal nerve stimulation, the vagus nerve causes a sudden fall in heart rate and blood pressure. Elevation in blood adrenaline level during pain or tension was noted, and its effects on vagovagal reflexes were studied. MATERIALS AND METHODS: Ten cats were used in the experiment. The vagus nerve was exposed on the right side of the neck by making an incision in the trachea, and a platinum electrode was attached to the vagus nerve on nerve's distal side. The head was tilted a 30 degree angle. The cats were divided into control and adrenaline-treated groups, and changes in cerebral blood flow, heart rate, and arterial pressure were compared between the two groups after electric stimulation of the vagus nerve. Cerebral blood flow was measured by the hydrogen clearance method. 1) Control group The vagus nerve was electrically stimulated for 1 minute. 2) Adrenaline-treated group The vagus nerve was electrically stimulated for 1 minute following 30 seconds of intravenous administration of adrenaline. RESULTS: Cerebral blood flow was significantly decreased in both the control and adrenaline-treated groups after electric stimulation, but the decrease was significantly greater in the latter group at all sites of measurement. Whereas heart rate and arterial pressure were significantly decreased in the control group, these variables in the adrenaline-treated group showed no significant change despite the greater decrease in cerebral blood flow. DISCUSSION: Heart rate, blood pressure, and cerebral blood flow were all significantly decreased after electric stimulation of the vagus nerve. These changes were considered owing to a fall in blood pressure due to vasodilation resulting from bradycardia and a relative decrease in sympathetic nervous tension resulting from electric stimulation. On the other hand, in the adrenaline-treated group, neither heart rate nor blood pressure showed any significant change, but cerebral blood flow was significantly decreased at all sites of measurement despite an adrenaline load. This contradictory results may be accounted for by the powerful beta 2-activity of adrenaline. The greater decrease in cerebral blood flow in the adrenaline-treated than in the control group can be attributed to decreased peripheral vascular resistance by its beta 2-activity. In the field of otorhinolaryngology the trigeminal region is often involved in the treatment of nasal disorders so that vagovagal reflexes are often encountered. The results of this study counsels caution in the treatment involving the trigeminal region.

Equivalent dipoles for middle latency auditory evoked potentials using the dipole tracing method.

During the last decade, new dipole localization techniques have prompted the search for the neuronal generators of evoked potentials. In this study we have reported the equivalent dipoles for the middle latency auditory evoked potentials (MAEPs) by the mean of these localization using the dipole tracing method. MAEPs that were recorded from 19 normal human subjects attending to random binaural clicks were analyzed using the dipole tracing method. Equivalent dipoles (EDs) were found, using both the single-dipole model and the two-dipole model, for components occurring from 0 to 60 ms after stimulus onset. The dipole analysis accounted for the real head geometry based on three-dimensional digitization of measured head shape, and the results were experimentally correlated to those of magnetic resonance imaging to increase the accuracy of ED localization. For components in the first 15 ms latency (P0 and Na), neither model provided EDs with reproducible high dipolality. Na was particularly difficult to analyze, as this component was often contaminated by myogenic potentials. The results provided by the two-dipole model for the Pa component (20-30 ms) showed three variations: in three subjects, one ED was located in each supratemporal cortex; in another three, one ED was located in the right temporal cortex and the other in the midbrain; and in the remaining thirteen subjects, both EDs were in the midbrain. The single-dipole model and the two-dipole model both found EDs in the midbrain for Nb. Further study is necessary to determine the cause or causes of the variety in our results. And it is also necessary to try the study using unilateral ear stimulation with/without contralateral masking noise for understanding the mechanism of the binaural interaction.

Leiomyoma with atypical cells (atypical leiomyoma) in the larynx.

AIMS: To report and confirm the identity of laryngeal leiomyoma with many atypical cells, which has not been described previously. CASE DETAILS: A 53-year-old man was found to have a polypoid tumour in the larynx. The tumour was excised and the patient has shown no evidence of recurrence over a 5-year period. The tumour tissue comprised intersecting fascicles of spindle-shaped tumour cells with blunt-ended nuclei. Many of the tumour cells showed marked atypia. Mitotic activity in the tumour cells was low, and no atypical mitoses were found. Immunohistochemically, the tumour cells were positive for smooth muscle actin and desmin. p53 overexpression was identified in many tumour cells; the p53 labelling index of the tumour cells was 45%. DNA from tumour cells showed loss of heterozygosity on chromosomes 3p, 5q, 8p, 9p, 10q, 17p and 18q. We diagnosed this case as leiomyoma with atypical cells (atypical leiomyoma) based on the clinical course and pathological and genetic findings. CONCLUSION: This is the first report of atypical leiomyoma in the larynx. The clinical course and pathological findings indicate that although laryngeal atypical leiomyoma contains numerous atypical cells, it is a benign neoplasm.