Cytoplasmic Dynein Heavy Chain 1b Is Required for Flagellar Assembly in Chlamydomonas

A second cytoplasmic dynein heavy chain (cDhc) has recently been identified in several organisms, and its expression pattern is consistent with a possible role in axoneme assembly. We have used a genetic approach to ask whether cDhc1b is involved in flagellar assembly in Chlamydomonas. Using a modified PCR protocol, we recovered two cDhc sequences distinct from the axonemal Dhc sequences identified previously. cDhc1a is closely related to the major cytoplasmic Dhc, whereas cDhc1b is closely related to the minor cDhc isoform identified in sea urchins, Caenorhabditis elegans, and Tetrahymena. TheChlamydomonas cDhc1b transcript is a low-abundance mRNA whose expression is enhanced by deflagellation. To determine its role in flagellar assembly, we screened a collection of stumpy flagellar (stf) mutants generated by insertional mutagenesis and identified two strains in which portions of the cDhc1bgene have been deleted. The two mutants assemble short flagellar stumps (<1–2 μm) filled with aberrant microtubules, raft-like particles, and other amorphous material. The results indicate that cDhc1b is involved in the transport of components required for flagellar assembly in Chlamydomonas

Cloning and expression of a rat brain interleukin-1beta-converting enzyme (ICE)-related protease (IRP) and its possible role in apoptosis of cultured cerebellar granule neurons

Several members of the IL-1beta-converting enzyme (ICE) family of proteases recently have been implicated in the intracellular cascade mediating the apoptotic death of various cell types. It is unclear, however, whether ICE-related proteases are involved in apoptosis of mammalian neurons and, if so, how they are activated. Here we report the cloning of an ICE-related protease (IRP) from rat brain, which displays strong sequence identity to human CPP32. In situ hybridization histochemistry reveals that this IRP mRNA is expressed in neuron-enriched regions of the developing and adult rat brain but is profoundly downregulated in the adult (compared with developing) brain. To investigate whether this IRP is involved in the death of neurons in the developing brain, we studied IRP expression in cultured cerebellar granule neurons. In cultured cerebellar granule neurons, reduction of extracellular K+ reliably induces apoptosis and stimulates overexpression of IRP mRNA. The latter is especially prominent 4 hr after switching from high K+ to low K+ medium. The expression of IRP mRNA was maintained at this level for at least 8 hr and was followed by apoptotic death of these neurons. Induction of IRP mRNA and cell death are blocked completely by adding depolarizing concentrations of K+ </=90 min after switching to low K+ medium (i.e., before the commitment point for apoptosis) and partially blocked by brain-derived neurotrophic factor (BDNF), which also partially rescues granule neurons from low K+-induced apoptosis. In addition, overexpression of IRP cDNA in HeLa cells results in cell death accompanied by strong internucleosomal cleavage of DNA, a typical feature of apoptosis. Finally, we detected cleavage of the putative death substrate poly (ADP-ribose) polymerase (PARP), beginning 8 hr after changing from high K+ to low K+ medium, coinciding with the time course of induced expression of the IRP gene. Our data suggest that transcriptional activation of IRP could be one of the mechanisms involved in the apoptotic death of cerebellar granule neurons

Return to Fort Rock Cave: Assessing the Site\u27s Potential to Contribute to Ongoing Debates about how and when Humans Colonized the Great Basin

Oregon’s Fort Rock Cave is iconic in respect to both the archaeology of the northern Great Basin and the history of debate about when the Great Basin was colonized. In 1938, Luther Cressman recovered dozens of sagebrush bark sandals from beneath Mt. Mazama ash that were later radiocarbon dated to between 10,500 and 9350 cal B.P. In 1970, Stephen Bedwell reported finding lithic tools associated with a date of more than 15,000 cal B.P., a date dismissed as unreasonably old by most researchers. Now, with evidence of a nearly 15,000-year-old occupation at the nearby Paisley Five Mile Point Caves, we returned to Fort Rock Cave to evaluate the validity of Bedwell’s claim, assess the stratigraphic integrity of remaining deposits, and determine the potential for future work at the site. Here, we report the results of additional fieldwork at Fort Rock Cave undertaken in 2015 and 2016, which supports the early Holocene occupation, but does not confirm a pre–10,500 cal B.P. human presence

Characterizing Emerging Canine H3 Influenza Viruses.

The continual emergence of novel influenza A strains from non-human hosts requires constant vigilance and the need for ongoing research to identify strains that may pose a human public health risk. Since 1999, canine H3 influenza A viruses (CIVs) have caused many thousands or millions of respiratory infections in dogs in the United States. While no human infections with CIVs have been reported to date, these viruses could pose a zoonotic risk. In these studies, the National Institutes of Allergy and Infectious Diseases (NIAID) Centers of Excellence for Influenza Research and Surveillance (CEIRS) network collaboratively demonstrated that CIVs replicated in some primary human cells and transmitted effectively in mammalian models. While people born after 1970 had little or no pre-existing humoral immunity against CIVs, the viruses were sensitive to existing antivirals and we identified a panel of H3 cross-reactive human monoclonal antibodies (hmAbs) that could have prophylactic and/or therapeutic value. Our data predict these CIVs posed a low risk to humans. Importantly, we showed that the CEIRS network could work together to provide basic research information important for characterizing emerging influenza viruses, although there were valuable lessons learned

Reliability and criterion validity of self-measured waist, hip, and neck circumferences

Abstract Background Waist, hip, and neck circumference measurements are cost-effective, non-invasive, useful markers for body fat distribution and disease risk. For epidemiology and intervention studies, including body circumference measurements in self-report surveys could be informative. However, few studies have assessed the test-retest reliability and criterion validity of a self-report tool feasible for use in large scale studies. Methods At home, mothers of young children viewed a brief, online instructional video on how to measure their waist, hip, and neck circumferences. Afterwards, they created a homemade paper measuring tape from a downloaded file with scissors and tape, took all measurements in duplicate, and entered them into an online survey. A few weeks later, participants visited an anthropometrics lab where they measured themselves again, and trained technicians (n = 9) measured participants in duplicate using standard equipment and procedures. To assess differences between self- and technician-measured circumferences, duplicate measurements for participant home self-measurements, participant lab self-measurements, and technician measurements each were averaged and Wilcoxon signed-rank tests conducted. Agreement between all possible pairs of measurements were examined using Intraclass Correlations (ICCs) and Bland-Altman plots. Results Participants (n = 41; aged 38.05 ± 3.54SD years; 71 % white) were all mothers that had at least one child under the age of 12 yrs. Technical error of measurements for self- and technician- duplicate measurements varied little (0.08 to 0.76 inches) and had very high reliability (≥0.90). Intraclass Correlations (ICC) comparing self vs technician were high (0.97, 0.96, and 0.84 for waist, hip, and neck). Comparison of self-measurements at home vs lab revealed high test-retest reliability (ICC ≥ 0.87). Differences between participant self- and technician measurements were small (i.e., mean difference ranged from −0.13 to 0.06 inches) with nearly all (≥93 %) differences within Bland-Altman limits of agreement and <10 % exceeding the a priori clinically meaningful difference criterion. Conclusions This study has demonstrated a simple, inexpensive method for teaching novice mothers of young children to take their own body circumferences resulting in accurate, reliable data. Thus, collecting self-measured and self-reported circumference data in future studies may be a feasible approach in research protocols that has potential to expand our knowledge of body composition beyond that provided by self-reported body mass indexes

Cloning and Expression of a Rat Brain Interleukin-1�-Converting Enzyme (ICE)-Related Protease (IRP) and Its Possible Role in Apoptosis of Cultured Cerebellar Granule Neurons

Several members of the IL-1�-converting enzyme (ICE) family of proteases recently have been implicated in the intracellular cascade mediating the apoptotic death of various cell types. It is unclear, however, whether ICE-related proteases are involved in apoptosis of mammalian neurons and, if so, how they are activated. Here we report the cloning of an ICE-related protease (IRP) from rat brain, which displays strong sequence identity to human CPP32. In situ hybridization histochemistry reveals that this IRP mRNA is expressed in neuron-enriched regions of the developing and adult rat brain but is profoundly downregulated in the adult (compared with developing) brain. To investigate whether this IRP is involved in the death of neurons in the developing brain, we studied IRP expression in cultured cerebellar granule neurons. In cultured cerebellar granule neurons, reduction of extracellular K � reliably induce