Chronological changes in cerebral air embolism that occurred during continuous drainage of infected lung bullae

We present a 43-year-old man with cerebral air embolism that occurred during continuous drainage of infected lung bullae. This complication is extremely rare, and may have been caused by the passage of air into the pulmonary venous circulation through a bronchovenous fistula and/or damaged pulmonary vessels. Air densities were demonstrated along the right frontal gyri on a CT performed 1 h after the onset of embolism, then moved to the deep cortex after 2.5 h. Three days later, a cortical infarct accompanied with extensive white matter edema in the right frontal lobe was confirmed by MRI. These CT and MRI findings may indicate the passage of intravascular air from the superficial to the deep cortex and subsequent cerebral infarction.     

Gonadotropin-releasing hormone exhibits circadian rhythm in phase with arginine-vasopressin in co-cultures of the female rat preoptic area and suprachiasmatic nucleus

To determine whether the suprachiasmatic nucleus can drive a circadian release of gonadotropin-releasing hormone (GnRH) in the preoptic area, we measured the release of GnRH, arginine-vasopressin and vasoactive intestinal polypeptide (VIP) in cocultures of the preoptic area and the suprachiasmatic nucleus at 2-h intervals over a period of 120 h. The release of GnRH in cocultures exhibited a significant circadian rhythm in the presence of oestrogen but not in the absence of oestrogen. The period of the GnRH circadian rhythm was the same as that of the arginine-vasopressin circadian rhythm, and different from the VIP circadian rhythm in each coculture. Furthermore, the peak phase of the GnRH rhythm occurred at the time same as that of the arginine-vasopressin rhythm in each coculture. However, the peak phase of the GnRH rhythm was not always the same as that of the VIP rhythm. Administration of arginine-vasopressin significantly increased GnRH release in single preoptic area cultures in the presence of oestrogen, but VIP did not. The result suggests that, in cocultures of the suprachiasmatic nucleus and the preoptic area, arginine-vasopressin neurones drive the circadian release of GnRH in the presence of oestrogen. We suggest that arginine-vasopressin neurones in the suprachiasmatic nucleus mediate the clock information to GnRH neurones in vivo as well.     

Transfection of antisense core 2 beta1,6-N-acetylglucosaminyltransferase-1 cDNA suppresses selectin ligand expression and tissue infiltration of B-cell precursor leukemia cells.

B-cell precursor (BCP) leukemia cells infiltrate into peripheral organs and the disease often relapses. Inhibition of tissue infiltration may improve the treatment outcome of BCP-leukemia patients. Selectin ligand has been suggested to play an important role in the infiltration of leukemia cells. However, the regulation mechanisms and involvement in tissue infiltration of selectin ligand expression in BCP-leukemia cells are not fully understood. In this study, we report that BCP-leukemia cells express selectin ligand on O-sialoglycoproteins. Core 2 beta1,6-N-acetylglucosaminyltransferase-1 (C2GnT-1) is mainly expressed in BCP-leukemia cells. Transfection of the antisense C2GnT-1 cDNA resulted in a significant reduction of either selectin ligand expression or selectin-dependent cell adhesion in BCP-leukemia cell line KM3 cells. Migration ability into mouse peripheral organs was reduced significantly in the antisense transfectant. These findings suggest that C2GnT-1 regulates selectin ligand expression. Downregulation of the selectin ligand expression level inhibits tissue infiltration of BCP-leukemia cells. C2GnT-1 may be a candidate of therapeutic target for the inhibition of infiltration of leukemia cells.     

Metabolite alterations in basal ganglia associated with psychiatric symptoms of abstinent toluene users: a proton MRS study.

Long-term toluene abuse causes a variety of psychiatric symptoms. However, little is known about abnormalities at the neurochemical level in the living human brain after long-term exposure to toluene. To detect neurochemical changes in the basal ganglia of subjects with a history of long-term toluene use, proton magnetic resonance spectroscopy (1H MRS) was performed in 12 abstinent toluene users and 13 healthy comparisons with no history of drug abuse. N-acetylaspartate (NAA), creatine plus phosphocreatine (Cr + PCr), choline-containing compounds (Cho), and myo-inositol (MI) levels were measured in the left and right basal ganglia. The Cho/Cr + PCr ratio, a marker of membrane metabolism, was significantly increased in the basal ganglia of toluene users in comparison to that of the control subjects. Furthermore, the increase in the Cho/Cr + PCr ratio was significantly correlated with the severity of residual psychiatric symptoms. These findings suggest that long-term toluene use causes membrane disturbance in the basal ganglia, which is associated with residual psychiatric symptoms that persist even after long-term abstinence from toluene use.     

Reduced anxious behavior in mice lacking the CCK2 receptor gene.

Cholecystokinin 2 (CCK2) receptors have been implicated as mediators of anxiety in standard mouse models such as exploratory behavior both in black and white test boxes and in elevated plus-mazes. We investigated the role of the CCK2 receptor in anxiety by evaluating the behavior of mice lacking the gene for this receptor in these standard anxiety models (i.e., exploratory behavior in a black and white test box and exploratory behavior in an elevated plus-maze). In the black and white test box, mice lacking the CCK2 receptor gene showed significantly increased numbers of transitions between the boxes compared to control mice. In the elevated plus-maze, mice lacking the CCK2 receptor gene displayed significantly more head dips than control mice. These results suggest that mice lacking the CCK2 receptor gene are less anxious than normal mice.     

Confirmation of brevetoxin metabolism in cockle, Austrovenus stutchburyi, and greenshell mussel, Perna canaliculus, associated with New Zealand neurotoxic shellfish poisoning, by controlled exposure to Karenia brevis culture.

We examined metabolism of PbTxs in New Zealand cockle, Austrovenus (A.) stutchburyi, and greenshell mussel, Perna (P.) canaliculus, by means of liquid chromatography coupled with tandem mass spectrometry. PbTx-2, PbTx-3 and BTX-B5 were detected in Karenia (K.) brevis culture medium in the ratio of ca. 50:2:5. The amounts of PbTx-3 and BTX-B5 were greatly increased in both seawater and shellfish exposed to K. brevis cultures or supernatant prepared by disruption of K. brevis under appropriate condition, while those of PbTx-2 were decreased. Some PbTx-2 was present in P. canaliculus, but not in A. stutchburyi. Low levels of BTX-B1 were detected in A. stutchburyi, but not P. canaliculus. Levels of PbTx-3 and BTX-B5 were highest immediately after exposure and then declined rapidly in both shellfish. BTX-B1 increased in concentration after exposure, and was then gradually eliminated from A. stutchburyi. Three successive exposures of A. stutchburyi to K. brevis cultures resulted in similar initial levels of PbTx-3 and BTX-B5, while BTX-B1 accumulated after each dose. In P. canaliculus, initial levels of PbTx-3 were similar, while PbTx-2 and BTX-B5 accumulated after each dose. PbTx-3 and BTX-B5 are proposed to be suitable markers for monitoring shellfish toxicity after a red tide event.     

Atrial Fibrillation-triggered Ventricular Fibrillation in a Patient with Early Repolarization Syndrome

A 54-year-old man with early repolarization syndrome (ERS) implanted with an implantable cardioverter-defibrillator (ICD) developed persistent atrial fibrillation (AF) three years after the implantation. Similarly, the remote monitoring system begun frequently detecting ventricular fibrillation (VF) and polymorphic ventricular tachycardia (PVT). Longer RR intervals were repeatedly observed just before the initiation of PVT/VF. Catheter ablation for AF successfully diminished both the PVT and VF events.     

Quantitative Evaluations of Posterior Staphylomas in Highly Myopic Eyes by Ultra-Widefield Optical Coherence Tomography

PurposeTo determine the shape of posterior staphylomas using ultra-widefield optical coherence tomographic (UWF-OCT) images and to identify the factors contributing to the shape and grade of the staphylomas in eyes with pathologic myopia.MethodsThis was an observational case series study. Highly myopic patients who were ≥40 years old with wide or narrow type of macular staphylomas were studied. High myopia was defined as a myopic refractive error (spherical equivalent) greater than −8.0 diopters (D) or an axial length (AL) > 26.5 mm. The maximum diameter and depth of the staphylomas were measured in the 12 radial scans of UWF-OCT images by ImageJ software and were compared between the two types of staphylomas.ResultsWe studied 197 eyes of 138 patients with a mean age of 64.7 ± 10.4 years and mean AL of 30.0 ± 1.9 mm. The AL was significantly longer in the eyes with the narrow type than the wide type of staphyloma (P = 0.036). Multiple regression analyses showed that age was significantly correlated with the maximum depth/maximum diameter ratio (wide type, P < 0.001; narrow type, P = 0.003) of both types of staphylomas. The AL was significantly correlated with the depth/diameter ratio of only the narrow type of staphylomas (P = 0.005).ConclusionsThe significant correlations of age and AL with the wide and narrow types of posterior staphylomas indicate that the factors for their formations may be distinctly different. Quantitative analyses of UWF-OCT images are helpful in determining the shape of the staphylomas.