8 research outputs found
Anti-NMDAR encephalitis in a 19 year old female patient with ovarian teratoma: A case report
Background: Anti-N-Methyl-d-Aspartate encephalitis is a subcategory of auto-immune encephalitis. It is known for its aggressive presenting symptoms and rapid deterioration, yet it is treatment responsive. It is associated in 50 % to ovarian teratoma. Case: We report the case of a 19Â year old female patient presenting for a psychiatric disorder of sudden onset with rapid deterioration. Neurologic imaging was in favor of encephalitis, and CSF studies revealed Anti NMDA receptors. Further abdominal imaging showed a right ovarian teratoma of 4Â cm.Laparoscopic ovarian cyst resection was done, and corticotherapy, IVIG and anticonvulsants were given. We report complete resolution of symptoms after 7 months. Conclusion: Anti-NMDA receptor encephalitis with ovarian teratoma is a rare entity with rapid deterioration. Early diagnosis, surgical resection and proper medical treatment are essential for the management of this disease
Ultraslow Myosin Molecular Motors of Placental Contractile Stem Villi in Humans
Human placental stem villi (PSV) present contractile properties. In vitro mechanics were investigated in 40 human PSV. Contraction of PSV was induced by both KCl exposure (n = 20) and electrical tetanic stimulation (n = 20). Isotonic contractions were registered at several load levels ranging from zero-load up to isometric load. The tension-velocity relationship was found to be hyperbolic. This made it possible to apply the A. Huxley formalism for determining the rate constants for myosin cross-bridge (CB) attachment and detachment, CB single force, catalytic constant, myosin content, and maximum myosin ATPase activity. These molecular characteristics of myosin CBs did not differ under either KCl exposure or tetanus. A comparative approach was established from studies previously published in the literature and driven by mean of a similar method. As compared to that described in mammalian striated muscles, we showed that in human PSV, myosin CB rate constants for attachment and detachment were about 103 times lower whereas myosin ATPase activity was 105 times lower. Up to now, CB kinetics of contractile cells arranged along the long axis of the placental sheath appeared to be the slowest ever observed in any mammalian contractile tissue
Changes in PSV contractile activity were induced by means of either electrical tetanus (panels A and B) or KCl exposure (panels C and D).
<p>Panels A and C: PSV shortening length versus time curves; Panels B and D: PSV tension versus time curves. Just after the onset of stimulus, a slow isotonic shortening at basal tone began, and reached a plateau. Basal tone was the load imposed to the PSV which induced neither shortening nor lengthening of PSV before both KCl exposure and electrical tetanus. PSV was then abruptly submitted to isometric conditions. After a brief overshoot due to the load clamp, PSV tension progressively decreased towards a plateau representing the total isometric tension.</p
Mechanical parameters of human placental stem villi (PSV) and molecular myosin characteristics under electrical tetanus and KCl [0.05M].
<p>Vo: PSV maximum velocity at zero-load; Po: PSV peak isometric tension; G: curvature of the hyperbolic T-V relationship; CB attachment (f<sub>1</sub>) and detachment (g<sub>1</sub> and g<sub>2</sub>) constants; π: CB unitary force; k<sub>cat</sub>: catalytic constant; max.ATPase: maximum myosin ATPase activity. Values are means ±SD. For all parameters presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108814#pone-0108814-t001" target="_blank">Table 1</a>, there was no statistical difference between tetanus and KCl exposure by applying the unpaired t test and as attested by the p-values.</p><p>Mechanical parameters of human placental stem villi (PSV) and molecular myosin characteristics under electrical tetanus and KCl [0.05M].</p