Case of Mitral Valve Prolapse - Associated Sudden Cardiac Death in Pregnancy.

BACKGROUND Mitral valve prolapse (MVP) is a frequent echocardiographic finding that can be accompanied by symptoms ranging from a benign course to occasionally catastrophic complications, such as heart failure, and rarely, sudden cardiac death. Female sex, younger age, physiological or psychological stress, electrical instability, and changes in the structure of the mitral apparatus all seem to be risk factors for fatal ventricular arrhythmias in patients with MVP. We report a case of MVP-related cardiac arrest in a pregnant woman, which is rarely reported. CASE REPORT A 34-year-old woman who had collapsed at home from cardiac arrest was transported to the hospital. She had no history of cardiac diseases and was 8 weeks pregnant. Premature ventricular complexes and sinus tachycardia were observed on the 12-lead electrocardiogram as she arrived at the Emergency Department. The second cardiac arrest she experienced while in the hospital was observed to be from torsades de pointes. Further investigations revealed severe mitral valve regurgitation due to posterior leaflet prolapse and regional hypokinesis of the inferior wall and interventricular septum. CONCLUSIONS Ventricular arrhythmia is a frequent finding of mitral valve regurgitation. However, it rarely results in serious consequences. Malignant arrhythmic mitral valve regurgitation can result in sudden cardiac death; therefore, physicians need to be aware of patients with MVP who exhibit characteristics of a potential high-risk profile in order to avoid tragic outcomes.

Effects of steaming on saponin compositions and antiproliferative activity of Vietnamese ginseng.

BACKGROUND: Steaming of ginseng is known to change its chemical composition and biological activity. This study was carried out to investigate the effect of different steaming time-scales on chemical constituents and antiproliferative activity of Vietnamese ginseng (VG). METHODS: VG was steamed at 105°C for 2-20 h. Its saponin constituents and antiproliferative activity were studied. The similarity of chemical compositions between steamed samples at 105°C and 120°C were compared. RESULTS: Most protopanaxadiol and protopanaxatriol ginsenosides lost the sugar moiety at the C-20 position with 10-14 h steaming at 105°C and changed to their less polar analogues. However, ocotillol (OCT) ginsenosides were reasonably stable to steaming process. Antiproliferative activity against A549 lung cancer cells was increased on steaming and reached its plateau after 12 h steaming. CONCLUSION: Steaming VG at 105°C showed a similar tendency of chemical degradation to the steaming VG at 120°C except the slower rate of reaction. Its rate was about one-third of the steaming at 120°C.

Processed Vietnamese ginseng: Preliminary results in chemistry and biological activity.

BACKGROUND: This study was carried out to investigate the effect of the steaming process on chemical constituents, free radical scavenging activity, and antiproliferative effect of Vietnamese ginseng. METHODS: Samples of powdered Vietnamese ginseng were steamed at 120°C for various times and their extracts were subjected to chemical and biological studies. RESULTS: Upon steaming, contents of polar ginsenosides, such as Rb1, Rc, Rd, Re, and Rg1, were rapidly decreased, whereas less polar ginsenosides such as Rg3, Rg5, Rk1, Rk3, and Rh4 were increased as reported previously. However, ocotillol type saponins, which have no glycosyl moiety at the C-20 position, were relatively stable on steaming. The radical scavenging activity was increased continuously up to 20 h of steaming. Similarly, the antiproliferative activity against A549 lung cancer cells was also increased. CONCLUSION: It seems that the antiproliferative activity is closely related to the contents of ginsenoside Rg3, Rg5, and Rk1.

Effect of neuropeptide Y Y2 receptor deletion on emotional stress-induced neuronal activation in mice.

In different behavioral paradigms including the elevated plus maze (EPM), it was observed previously that deletion of the neuropeptide Y Y2 receptor subtype results in potent suppression of anxiety-related and stress-related behaviors. To identify neurobiological correlates underlying this behavioral reactivtiy, expression of c-Fos, an established early marker of neuronal activation, was examined in Y2 receptor knockout (Y2(-/-)) vs. wildtype (WT) mice. Mice were placed on the open arm (OA) or closed arm (CA) of the EPM for 10 min and the effect on regional c-Fos expression in the brain was investigated. The number of c-Fos positive neurons was significantly increased in both WT and Y2(-/-) lines after OA and CA exposure in 51 of 54 regions quantified. These regions included various cortical, limbic, thalamic, hypothalamic, and hindbrain regions. Genotype influenced c-Fos responses to arm exposures in 6 of the 51 activated regions: the cingulate cortex, barrel field of the primary somatosensory cortex, nucleus accumbens, dorsal lateral septum, amygdala and lateral periaqueductal gray. These differences in neuronal activity responses to the novel environments were more pronounced after OA than after CA exposure. Mice lacking Y2 receptors exhibited reduced neuronal activation when compared to WT animals in response to the emotional stressors. Reduced neuronal excitability in the identified brain areas relevant to the processing of motivated, explorative as well as anxiety-related behaviors is suggested to contribute to the reduced anxiety-related behavior observed in Y2(-/-) mice.

Conditional CRF receptor 1 knockout mice show altered neuronal activation pattern to mild anxiogenic challenge.

RATIONALE: Regional-specific corticotropin-releasing factor receptor 1 (CRF-R1) knockout mice have been generated recently as a tool to dissociate CNS functions modulated by this receptor. In these mice, CRF-R1 function is postnatally inactivated in the anterior forebrain including limbic brain structures but not in the pituitary leading to normal activity of the hypothalamic-pituitary-adrenocortical (HPA) axis under basal conditions and reduced anxiety-related behavior in the light-dark box and the elevated plus maze (EPM) as compared to wild-type (WT) mice (Müller et al., Nat Neurosci 6:1100-1107, 2003). OBJECTIVE: To identify neurobiological correlates underlying this reduced anxiety-like behavior, the expression of c-Fos, an established marker for neuronal activation, which was examined in response to a mild anxiogenic challenge. MATERIALS AND METHODS: Mice were placed for 10 min on the open arm (OA) of the EPM, and regional c-Fos expression was investigated by immunohistochemistry. RESULTS: OA exposure enhanced c-Fos expression in both conditional CRF-R1 knockout and WT mice in a number of brain areas (39 of 55 quantified), including cortical, limbic, thalamic, hypothalamic, and hindbrain regions. The c-Fos response in conditional CRF-R1 knockout animals was reduced in a restricted subset of activated neurons (4 out of 39 regions) located in the medial amygdala, ventral lateral septum, prelimbic cortex, and dorsomedial hypothalamus. CONCLUSIONS: These results underline the importance of limbic CRF-R1 in modulating anxiety-related behavior and suggest that reduced neuronal activation in the identified limbic and hypothalamic key structures of the anxiety circuitry may mediate or contribute to the anxiolytic-like phenotype observed in mice with region-specific deletion of forebrain CRF-R1.