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ABSTRACTNeospora caninum, a causative agent of bovine abortions, is an apicomplexan parasite that is closely related to the human pathogen Toxoplasma gondii. Since a number of intracellular parasites, including T. gondii, have been shown to modulate host cell apoptosis, the present study was conducted to establish whether N. caninumis similarly capable of subverting apoptotic pathways in its host cells. Our results indicated that death receptor-mediated apoptosis is repressed during N. caninuminfection, and the data further showed that the executioner caspase, caspase 3, does not become activated in the infected cells. Surprisingly, nuclear translocation of the NF-κB subunit p65 was not detected in N. caninum-infected cells, although this host transcription factor has been shown to upregulate prosurvival genes in cells infected with T. gondii. Consistent with these findings, the distinct accumulation of phosphorylated IκB that is seen at the parasitophorous vacuole membrane (PVM) of T. gondiiwas not apparent on the N. caninumPVM. Although a putative IκB kinase activity was detected in N. caninumextracts, thereby implying that this parasite is capable of modulating NF-κB translocation into the host cell nucleus, the data collectively suggest that a profound and sustained activation of the NF-κB pathway is not central to the ability of N. caninumto prevent apoptosis of their host cells.

Neospora caninum, a causative agent of bovine abortions, is an apicomplexan parasite that is closely related to the human pathogen Toxoplasma gondii. Since a number of intracellular parasites, including T. gondii, have been shown to modulate host cell apoptosis, the present study was conducted to establish whether N. caninum is similarly capable of subverting apoptotic pathways in its host cells. Our results indicated that death receptor-mediated apoptosis is repressed during N. caninum infection, and the data further showed that the executioner caspase, caspase 3, does not become activated in the infected cells. Surprisingly, nuclear translocation of the NF-B subunit p65 was not detected in N. caninum-infected cells, although this host transcription factor has been shown to upregulate prosurvival genes in cells infected with T. gondii. Consistent with these findings, the distinct accumulation of phosphorylated IB that is seen at the parasitophorous vacuole membrane (PVM) of T. gondii was not apparent on the N. caninum PVM. Although a putative IB kinase activity was detected in N. caninum extracts, thereby implying that this parasite is capable of modulating NF-B translocation into the host cell nucleus, the data collectively suggest that a profound and sustained activation of the NF-B pathway is not central to the ability of N. caninum to prevent apoptosis of their host cells.

A hypothesis about the relationship between prosodic structure and discourse structure in English was tested by taking into consideration explicit models of both intonational structure and discourse structure in constructing the experimental corpus. In the experiment, a corpus of discourses with controlled structure was read by speakers. Matched pairs of utterances were extracted from different positions in the discourses. These pairs were played to listeners to test whether the discourse position was distinguishable. The utterances were then ToBI transcribed in order to test whether the same dominance relationships in the discourses are reflected by the same edge tones. Then, pairs which were perceptually distinct were examined for tonal similarity. Finally, pairs of utterances which were perceptually distinct and which had similar tones were analyzed acoustically for phonetic differences. Several trends emerged in the acoustic analysis, including differences in fundamental frequency, root mean square amplitude, and duration. These phonetic factors were thus bearing the functional load of indicating more global aspects of discourse structure.

Prenatal androgen shapes genital differentiation. In humans, genital anatomy determines sex of rearing and subsequent behavioral development. Rhesus monkey genital anatomy and neuroendocrine function are sexually differentiated, and behavioral development occurs in a complex social environment. We investigated prenatal hormonal influences on sexual differentiation by suppressing or increasing androgens in male and female rhesus monkeys. Pregnant multiparous female rhesus monkeys received 35–40 days of testosterone enanthate (TE) treatment, androgen antagonist (flutamide, FL) treatment, or vehicle starting on gestation day (GD) 35 or 40 (early) or GD 110 or 115 (late). Exogenous androgen increased neonatal LH secretion in females when given early and altered female genital differentiation when administered either early or late. TE treatment, early or late in gestation, had no measurable effects on male genital differentiation or neuroendocrine function. Early FL treatment, however, radically altered male genital differentiation, producing in two cases males with a urethral opening separate from the glans. In females, early FL treatment produced detectable alterations in genitalia consistent with a reduced exposure to prenatal androgen, suggesting that female rhesus monkeys are naturally exposed prenatally to meaningful levels of T. Late FL treatment reduced male penis size and increased neonatal T secretion, but had no effect in females. This is the first study to block endogenous prenatal testosterone in rhesus monkeys, thereby altering sexual differentiation. These findings illustrate the complexity of prenatal influences on anatomical and neuroendocrine development. The relationship between the anatomical changes reported here and sex differences in behavior is currently under investigation.

The article discusses various reports published within the issue of "Sesame Street magazine", including "Bedtime on Sesame Street," "Dream a Little Dream," and "In a Flash."

The article discusses various reports published within the issue, including "Birthday Breakfast," which features the Sesame Street friends as they sit down to a morning meal.

The author reflects on her experience at the Music in the Valley course near Haifa, Israel. She explains that the course takes place on a kibbutz offering individual lessons, chamber music rehearsals, Alexander technique classes, master classes, and concerts. She also discusses her experience with the cello choir. The author mentions cello teachers Hillel Zori, Zvi Plesser, and Dudu Sella.

The article discusses various reports published within the issue, including one about traveling to distant places and another on animal migration.

The author discusses the opportunity posed by the Thanksgiving season to instill in children the importance of giving back.

The article discusses various reports published within the issue, including one which focuses on a cooperative story about holiday dinner and another which provides information on temperature.

A letter to the editor is presented in response to the article "'One Stop' Research Shop Seen as Slow to Yield Views That Educators Can Use," published in the September 27, 2006 issue.

Introduces a series of articles related to children's activities.

The article discusses various topics published within the March 2006 issue of "Sesame Street," including an article on board games.

Introduces a series of articles featured in the October 2005 issue of "Sesame Street Magazine."

Explores articles and topics related to Christmas stories and games for children.

Presents an overview of educational games and activities for children featured in the July 2004 issue of the periodical "Sesame Street."

Encourages parents to teach their children the art of dancing.

Features puppeteer Caroll Spinney. Sesame Street characters handled by Spinney.