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Little is known about the molecular mechanisms underlying the release of merozoites from malaria infected erythrocytes. In this study membranous structures present in the culture medium at the time of merozoite release have been characterized. Biochemical and ultrastructural evidence indicate that membranous structures consist of the infected erythrocyte membrane, the parasitophorous vacuolar membrane and a residual body containing electron dense material. These are subcellular compartments expected in a structure that arises as a consequence of merozoite release from the infected cell. Ultrastructural studies show that a novel structure extends from the former parasite compartment to the surface membrane. Since these membrane modifications are detected only after merozoites have been released from the infected erythrocyte, it is proposed that they might play a role in the release of merozoites from the host cell

Background: Normal sagittal cervical alignment has been associated with improved outcome after anterior cervical discectomy and fusion (ACDF)., Objective: The aim of this study is to identify alterations of cervical sagittal balance parameters after single-level ACDF and assess correlations with postoperative functionality., Methods: A retrospective chart review was performed between January 2010 and January 2014 to identify adult patients with no previous cervical spine surgery who underwent ACDF at any one level between C2 and C7 for the single-level degenerative disease. Tumor, infection, and trauma cases were excluded from the study. For the included cases, the following data were recorded preoperatively and 6 months-1 year after surgery: sagittal balance-marker measurements of the C1-C2 angle, C2-C7 angle, C7 slope, segmental angle at the operated level, and sagittal vertical axis (SVA) distance between C2 and C7, as well as the neck disability index and visual analog scale of pain., Results: The present study included 47 patients (average age: 51.2 years; range: 28-86 years). A moderate negative correlation between a smaller C2-C7 angle and the presence of right arm pain before treatment was found ( P = 0.0281). Postoperatively, functionality scores significantly improved in all patients. C1-C2 angle increased with statistical significance ( P = 0.0255). C2-C7 angle, segmental angle, C7 slope, and SVA C2-C7 distance did not change with statistical significance after surgery. C7 slope significantly correlated with overall cervical sagittal balance ( P < 0.05)., Conclusions: Single-level ACDF significantly increases upper cervical lordosis (C1-C2) without significantly changing lower cervical lordosis (C2-C7). The C7 slope is a significant marker of overall cervical sagittal alignment ( P < 0.05)., Competing Interests: There are no conflicts of interest.

Infected erythrocytes containing the more mature stages of the human malaria Plasmodium falciparum may adhere to endothelial cells and uninfected red cells. These phenomena, called sequestration and rosetting, respectively, are involved in both host pathogenesis and parasite survival. This review provides a critical summary of recent advances in the characterization of the molecules of the infected red blood cell involved in adhesion, i.e. parasite-encoded molecules (PfEMP1, MESA, rifins, stevor, clag 9, histidine-rich protein), a modified host membrane protein (band 3) and exofacial exposure of phosphatidylserine, as well as receptors on the endothelium, i.e. thrombospondin, CD36, ICAM-1 (intercellular adhesion molecule), and chondroitin sulfate.

Background: The preservation of implicit memory function during anesthesia is controversial, with conflicting results appearing in the literature. This study was designed to elucidate the effect of midazolam as part of an anesthetic technique on implicit memory function during anesthesia. Using a prospective randomized, double-blind study design, performance in three tasks (category generation, free association, and homophone spelling) was assessed., Methods: Forty-eight consenting patients were assigned to two equal groups, to receive 2 mg intravenous midazolam or normal saline before induction of anesthesia. Anesthesia was induced with fentanyl and propofol and maintained with isoflurane 1.3 MAC until incision and isoflurane 1.0 MAC in 70% nitrous oxide thereafter. Fentanyl was used for supplementation of anesthesia. During anesthesia, one of two 50-min tapes containing the test material was played to each patient on a portable cassette player. In the postanesthesia care unit and 48 h after surgery, patients were engaged in three tasks by an observer unaware of the treatment group or tape., Results: No significant main effect of priming or midazolam was observed in any of the tasks. In the word-association task, an interaction was observed between priming and treatment group (F = 9.62, P < .01) due to negative priming in the placebo group., Conclusions: The lack of a main effect of priming in any of the three tasks is consistent with the conclusion that indirect memory was not demonstrated for events occurring during the standard anesthetic conditions of this study. Further, midazolam appeared to have no effect.

Three experiments on memory for unfamiliar voices are reported. In the first two experiments, the type of encoding was manipulated by orienting tasks. In each study, one group rated the pleasantness of the voices, another group made judgments of pitch, and a third group performed no orienting task. Recognition memory was not correlated with encoding condition in either experiment. In Experiment 2, voice memory was better when the message remained constant from study to test than when it was changed. In Experiment 3, a group of blind adults was tested with no orienting task. The blind subjects' memory was equivalent to that of the appropriate sighted group of Experiment 2. It is proposed that voices represent a psychologically unitary stimulus that cannot be encoded with differing degrees of elaboration; therefore, voices are not sensitive to orienting tasks in the way that other classes of events, such as words and faces, are.

The effects of ratio length and shock intensity on bar pressing were examined in three rats in two escape-from-shock experiments. In Experiment I, shock intensity was held constant while the schedule was varied from FR 1 to FR 20. The latency of the first escape response increased with FR length while the escape rate, computed as over-all rate in shock minus latency of the first response, decreased at FR 20. In Experiment II, the schedule was held constant at FR 5 while shock intensity was manipulated. Latency decreased as intensity increased, while escape rate increased with intensity, passing through a maximum for two subjects. Responses occurring during the last 100 sec of the 2-min escape period decreased as the FR increased for all subjects, and decreased as shock intensity increased for two subjects.

This study concerns the use of a multiple stimulus discrimination procedure for producing data on the generalization of conditioned suppression. Four rats were maintained on a variable interval schedule of milk reinforcement in the presence of five stimuli varying in auditory click rate. When response rates were stable, electric shock was regularly paired with the termination of one of the click stimuli. For two rats the shock was paired with the slowest click rate, and for two rats shock was paired with the fastest click rate. The VI schedule remained in effect. Plots of the relative rates of response to each of the five stimuli yielded concave gradients for both animals suppressed at the slowest click rate, and flat gradients with a sharp drop at the warning stimulus for both animals suppressed at the fastest click rate. When the warning stimuli were reversed for both pairs of subjects, both gradient forms were reproduced. The present procedure was contrasted with procedures used by other investigators.