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Florida Administrative Code (FAC) 5E-2.0311, “Performance Standards and Acceptable Test Conditions for Preventive Termite Treatments for New Construction,” approved in 2003, currently remains without change as originally written. This Code requires broad revision to include updating existing and new termite management methods and technologies, describing acceptable testing protocols that objectively evaluate termite management product efficacy, and clearly and accurately define product performance standards required for approval and use in Florida, USA. This manuscript provides modification and expansion of the existing Code, first in outline form, then followed by a proposed complete revision including detailed explanations for each outline heading and sub-heading. Efficacy requirements, acceptable test conditions, and performance standards requirements are described for termite management products, materials, and non-chemical physical exclusion barriers. We also include testing protocols for field plot and structure efficacy tests. Minimum performance standards also are described for field plots and structure tests to include: (1) termiticide applications to soil, (2) termite baiting systems, (3) pesticides applied directly to wood and building components, (4) pesticide combination mixtures, and (5) new application technologies, products, and methodologies. Although this manuscript addresses revision of a specific Florida Administrative Code, it also is appropriate for consideration by the United States Environmental Protection Agency (USEPA) as well as regulatory entities in other states responsible for pesticide regulation and consumer protection services when writing or revising their code requirements for termite management.

Psocids are damaging stored-product pests. In this study, eggs and early-instar nymphs, adults, and all life stages of Liposcelis entomophila, L. decolor, L. bostrychophila, and L. paeta were subjected to 43, 50, or 75% (Control) relative humidity (RH) for 2, 4, 6, 8, 10, 12, 14, or 16 d at 30.0°C. All adults of these species died within 8 d at both 43 and 50% RH, except for L. bostrychophila, which required 12 d at 50% RH for 100% mortality to occur. For all life stages and eggs and early-instar nymphs, maximum survival times (times to 100% mortality) at 43 or 50% RH for L. entomophila, L. decolor, L. bostrychophila, and L. paeta, were 8 and 10 d, 8 and 12 d, 12 and 14 d, and 12 and 16 d, respectively. During this study, numbers of nymphs and adults of all species 14 d after the RH treatments increased within the 75% RH Control arenas. Different species and life stages responded differently to 43 and 50% RH, as time to kill all stages of the four psocid species was 8–12 and 10–16 d, respectively. Results indicate that using a specific RH environment may be effective in psocid management.

In 1995, the historical shipwreck of La Belle was discovered off the coast of Texas. One partial human skeleton was recovered from alongside cargo in the rear portion of the ship; a second (complete) skeleton was found atop coiled anchor rope in the bow. In late 2015, comprehensive forensic genetic testing began on multiple samplings from each set of remains. For the partial skeleton recovered from the ship's rear cargo area, results were obtained for 26/27 Y-STRs using traditional CE; with MPS technology, results were obtained for 18/24 Y-STRs, 56/56 ancestry-informative SNPs (aiSNPs), 22/22 phenotype-informative SNPs (piSNPs), 22/27 autosomal STRs, 4/7 X-STRs, and 94/94 identity-informative SNPs (iiSNPs). For the complete skeleton of the second individual, results were obtained for 7/17 Y-STRs using traditional CE; with MPS technology, results were obtained for 5/24 Y-STRs, 49/56 aiSNPs, 18/22 piSNPs, 15/27 autosomal STRs, 1/7 X-STRs, and 66/94 iiSNPs. Biogeographic ancestry for each set of skeletal remains was predicted using the ancestry feature and metapopulation tool of the Y-STR Haplotype Reference Database (YHRD), Haplogroup Predictor, and the Forensic Research/Reference on Genetics knowledge base (FROG-kb). Phenotype prediction was performed using piSNP data and the HIrisplex eye color and hair color DNA phenotyping webtool. mtDNA whole genome sequencing also was performed successfully. This study highlights the sensitivity of current forensic laboratory methods in recovering DNA from historical and archaeological human remains. Using advanced sequencing technology provided by MiSeq™ FGx (Verogen) and Ion S5™ (Thermo Fisher Scientific) instrumentation, degraded skeletal remains can be characterized using a panel of diverse and highly informative markers, producing data which can be useful in both forensic and genealogical investigations.

Coptotermes Wasmann is one of the most important genera of wood-destroying insect pests, both in its native and introduced countries. Pyrethroids are among the most widely used insecticides in wood preservation around the world. Consequently, they have often been evaluated against different species of Coptotermes. However, because various test methods have been used between countries, comparing results is problematic. These field trials, using a single aboveground method of exposure, assessed a range of retentions of two pyrethroids (bifenthrin and permethrin) in Pinus radiata D. Don sapwood against two species of Coptotermes in three countries to provide directly comparable results. Coptotermes acinaciformis (Froggatt) in Australia consumed the most nontreated wood, followed by Coptotermes formosanus Shiraki in China, then C formosanus in the United States, although these data were not significantly different. Both termite species demonstrated a dose-response to wood treated with the two pyrethroids; less wood was consumed as retention increased. Overall, C. acinaciformis consumed relatively little of the treated wood. In comparison, C. formosanus consumed 20–90% of the wood treated at the lowest retentions of the pyrethroids evaluated. Results indicated that C. acinaciformis was more sensitive to pyrethroid toxicity/ repellency compared with C. formosanus. Factors that may have influenced the results are discussed. However, using a single aboveground method of exposure across three countries, that suited both species of Coptotermes, made it possible to determine unambiguously the actual differences between the species in their tolerances to the two pyrethroid insecticides.

Porphyrias are disorders of heme metabolism frequently characterized by extreme photosensitivity. This symptom results from accumulation of porphyrins, tetrapyrrole intermediates in heme biosynthesis that generate reactive oxygen species when exposed to light, in the skin of affected individuals. Here we report that in addition to producing an ommochrome body pigment, the planarian flatworm Schmidtea mediterranea generates porphyrins in its subepithelial pigment cells under physiological conditions, and that this leads to pigment cell loss when animals are exposed to intense visible light. Remarkably, porphyrin biosynthesis and light-induced depigmentation are enhanced by starvation, recapitulating a common feature of some porphyrias – decreased nutrient intake precipitates an acute manifestation of the disease. Our results establish planarians as an experimentally tractable animal model for research into the pathophysiology of acute porphyrias, and potentially for the identification of novel pharmacological interventions capable of alleviating porphyrin-mediated photosensitivity or decoupling dieting and fasting from disease pathogenesis. DOI: http://dx.doi.org/10.7554/eLife.14175.001, eLife digest Porphyrias are rare diseases that involve ring-shaped molecules called porphyrins accumulating in various parts of the body. Porphyrins are produced as part of the normal process that makes an important molecule called heme, which is required to transport oxygen. However, high levels of porphyrins can be toxic. For example, porphyrins deposited in the skin can cause swelling and blistering when the skin is exposed to bright light. Other disease symptoms include neurological issues ranging from anxiety and confusion to seizures or paralysis. It has been speculated that porphyrias may have affected several historical figures, including the artist Vincent van Gogh. In addition to their role in heme production, porphyrins also have other roles. For example, they are used as pigments in the wing feathers of some owls. Researchers are trying to understand more about how organisms regulate porphyrin production so that it might be possible to develop more effective treatments for porphyria in humans. Here, Stubenhaus et al. studied how a flatworm called Schmidtea mediterranea makes porphyrins. A group of undergraduate students noticed that these animals – which are normally brown in color – turned white when they were exposed to sunlight for several days. Stubenhaus et al. found that S. mediterranea makes porphyrins in the pigment cells of its skin using the same genes that make porphyrins in humans. Together with other molecules called ommochromes, the porphyrins give rise to the normal color of this flatworm. However, when the animals are exposed to intense light for extended periods of time, which is unlikely to occur in the wild, porphyrin production leads to loss of the pigment cells. The experiments also show that starvation increases the rate of pigment cell loss in light-exposed flatworms, which mirrors the worsening of disease symptoms some porphyria patients experience when they diet or fast. Stubenhaus et al. propose that flatworms are useful models in which to study the molecular processes that are responsible for porphyrias in humans. Further research is required to determine the exact chemical structure of the porphyrin and ommochrome molecules produced in different flatworm species. Stubenhaus et al. also plan to use flatworms to screen for drugs that could potentially be developed into new treatments for porphyria. DOI: http://dx.doi.org/10.7554/eLife.14175.002

Studies of embryonic stem cells (ESCs) reveal that these cell lines can be derived from differing stages of embryonic development. We analyzed common changes in the expression of microRNAs (miRNAs) and mRNAs in 9 different human ESC (hESC) lines during early commitment and further examined the expression of key ESC-enriched miRNAs in earlier developmental states in several species. We show that several previously defined hESC-enriched miRNA groups (the miR-302, −17, and −515 families, and the miR-371–373 cluster) and several other hESC-enriched miRNAs are down-regulated rapidly in response to differentiation. We further found that mRNAs up-regulated upon differentiation are enriched in potential target sites for these hESC-enriched miRNAs. Interestingly, we also observed that the expression of ESC-enriched miRNAs bearing identical seed sequences changed dynamically while the cells transitioned through early embryonic states. In human and monkey ESCs, as well as human-induced pluripotent stem cells (iPSCs), the miR-371–373 cluster was consistently up-regulated, while the miR-302 family was mildly down-regulated when the cells were chemically treated to regress to an earlier developmental state. Similarly, miR-302b, but not mmu-miR-295, was expressed at higher levels in murine epiblast stem cells (mEpiSC) as compared with an earlier developmental state, mouse ESCs. These results raise the possibility that the relative expression of related miRNAs might serve as diagnostic indicators in defining the developmental state of embryonic cells and other stem cell lines, such as iPSCs. These data also raise the possibility that miRNAs bearing identical seed sequences could have specific functions during separable stages of early embryonic development.

Sequencing of a portion of the mitochondrial DNA 16S gene was undertaken to determine genetic variation and distribution of Reticulitermes in Oklahoma. From 16 Oklahoma counties, 43 R. flavipes, four R. hageni, one R. virginicus, and seven R. tibialis samples were collected, identified and subjected to DNA sequencing. No genetic variation was observed in R. virginicus, while two haplotypes were observed in R. hageni, four in R. tibialis, and 10 for R. flavipes. Among the 10 R. flavipes haplotypes, nine nucleotides were variable and genetic variation ranged from 0.2 to 1.4%. Phylogenetic analysis revealed several minor relationships within R. tibialis and R. flavipes; however, there was no apparent geographical association to the haplotypes. The high amount of genetic variation, but a lack of geographically distinct haplotypes in R. flavipes, indicate that this termite species has been distributed randomly in Oklahoma by humans due to its association with structures.

IPM strategies and tactics to reduce insecticide use while protecting structures from attack and infestation by subterranean termites are reviewed. Standard termiticide and product testing methods are presented. Results of USDA Forest Service field tests generally demonstrate that currently registered termiticides provide five or more years of termite control. Stainless steel mesh has been a 100% effective termite barrier for more than 6 yrs in continuing field tests.

Summary Objective The isocitrate dehydrogenase 1 (IDH1) R132H mutation is the most common mutation in World Health Organization (WHO) grade II gliomas, reported to be expressed in 70–80%, but only 5–10% of high grade gliomas. Low grade tumors, especially the protoplasmic subtype, have the highest incidence of tumor associated epilepsy (TAE). The IDH1 mutation leads to the accumulation of 2-hydroxyglutarate (2HG), a metabolite that bears a close structural similarity to glutamate, an excitatory neurotransmitter that has been implicated in the pathogenesis of TAE. We hypothesized that expression of mutated IDH1 may play a role in the pathogenesis of TAE in low grade gliomas. Methods Thirty consecutive patients with WHO grade II gliomas were analyzed for the presence of the IDH1-R132H mutation using immunohistochemistry. The expression of IDH1 mutation was semiquantified using open-source biologic-imaging analysis software. Results The percentage of cells positive for the IDH1-R132H mutation was found to be higher in patients with TAE compared to those without TAE (median and interquartile range (IQR) 25.3% [8.6–53.5] vs. 5.2% [0.6–13.4], p = 0.03). In addition, we found a significantly higher median IDH1 mutation expression level in the protoplasmic subtype of low grade glioma (52.2% [IQR 19.9–58.6] vs. 13.8% [IQR 3.9–29.4], p = 0.04). Significance Increased expression of the IDH1-R132H mutation is associated with seizures in low grade gliomas and also with the protoplasmic subtype. This supports the hypothesis that this mutation may play a role in the pathogenesis of both TAE and low grade gliomas.

Six wood products used in wall paneling were tested for resistance to feeding damage by the eastern subterranean termite, Reticulitermes fiavipes (Kollar). Alaska-cedar, Chamaecyparis nootkatensis (D. Don) Spach, fiber without wax and resin treatments normally used in paneling production was not a preferred food source in choice tests where all 6 wood products plus pine, Pinus palustris Mill., were simultaneously provided. However, the same nontreated Alaska-cedar fiber sustained severe damage when provided as the only food source in no-choice tests. Nontreated fiber of western hemlock, Tsuga heterophylla (Raf.) Sarg., and hardboard and hardboard paneling made from a mixture of western hemlock and Douglas-fir. Pseudotsuga menziesii (Mirb.) Franco, sustained significant feeding damage in both choice and no-choice feeding tests. Pressed paneling mats made from Alaska-cedar or western hemlock exhibited antifeedant properties. Waxes, resins, and additives used in manufacturing these mats imparted resistance to R. fiavipes .

Recombinant human tumor necrosis factor (TNF) binding protein-1 (r-h TBP-1) and recombinant human soluble dimeric TNF receptor (rhu TNFR:Fc) were used to determine the relative contributions of TNF to phorbol myristate acetate (PMA) and cytokine-induced human immunodeficiency virus type 1 (HIV-1) replication in chronically infected cell lines. Treatment of HIV-1-infected promonocytic U1 cells with r-h-TBP-1 or rhu TNFR:Fc reduced PMA-induced HIV-1 p24 antigen production in a concentration-dependent manner, with a maximal inhibition of approximately 90%. Maximal inhibition of p24 antigen production in T-lymphocytic ACH-2 cells was 47% with r-hTBP-1 and 42% with rhu TNFR:Fc. r-hTBP-1 and rhu TNFR:Fc also decreased p24 antigen synthesized by U1 cells in response to other stimuli, including phytohemagglutinin (PHA)-induced supernatant, granulocyte-macrophage colony-stimulating factor, interleukin-6, and TNF. Addition of r-hTBP-1 to U1 cells during the last 4 h of a 24 h incubation with PMA still inhibited p24 antigen production by 15%. U1 cells stimulated with 10(-7) M PMA released approximately 1 ng/ml endogenous TBP-1 with an initial peak observed at 1 h and a second peak at 24 h after PMA stimulation. r-hTBP-1 also partially reversed inhibition of U1 cellular proliferation caused by PMA. Both r-hTBP-1 and rhu TNFR:Fc blocked PMA induction of nuclear factor (NK)- kappa B DNA-binding activity in U1 cells in association with decreases in HIV-1 replication. We conclude that soluble TNF receptors can inhibit stimuli-induced HIV-1 expression and NK- kappa B DNA-binding activity in chronically infected U1 cells.

Viral drug toxicity, resistance, and an increasing immunosuppressed population warrant continued research into new avenues for limiting diseases associated with human cytomegalovirus (HCMV). In this study, a small interfering RNA (siRNA), siX3, was designed to target coding sequences within shared exon 3 of UL123 and UL122 transcripts encoding IE1 and IE2 immediate-early proteins of HCMV. Pretreatment of cells with siX3 reduced the levels of viral protein expression, DNA replication, and progeny virus production compared to control siRNA. Two siRNAs against UL54 and overlapping transcripts ( UL55-57 ) were compared to siX3 in HCMV infection and were also found to be effective at inhibiting HCMV replication. Further investigation into the effects of the siRNAs on viral replication showed that pretreatment with each of the siRNAs resulted in an inhibition in the formation of mature replication compartments. The ability of these siRNAs to prevent or reduce certain cytopathic effects associated with HCMV infection was also examined. Infected cells pretreated with siX3, but not siUL54, retained promyelocytic leukemia (PML) protein in cellular PML bodies, an essential component of this host intrinsic antiviral defense. DNA damage response proteins, which are localized in nuclear viral replication compartments, were reduced in the siX3- and siUL54-treated cells. siX3, but not siUL54, prevented DNA damage response signaling early after infection. Therapeutic efficacy was demonstrated by treating cells with siRNAs after HCMV replication had commenced. Together, these findings suggest that siRNAs targeting exon 3 of the major IE genes or the UL54-57 transcripts be further studied for their potential development into anti-HCMV therapeutics.

Low oxygen levels have been shown to promote self-renewal in many stem cells. In tumors, hypoxia is associated with aggressive disease course and poor clinical outcomes. Furthermore, many aggressive tumors have been shown to display gene expression signatures characteristic of human embryonic stem cells (hESC). We now tested whether hypoxia might be responsible for the hESC signature observed in aggressive tumors. We show that hypoxia, through hypoxia-inducible factor (HIF), can induce an hESC-like transcriptional program, including the induced pluripotent stem cell (iPSC) inducers, OCT4, NANOG, SOX2, KLF4, cMYC, and microRNA-302 in 11 cancer cell lines (from prostate, brain, kidney, cervix, lung, colon, liver, and breast tumors). Furthermore, nondegradable forms of HIFα, combined with the traditional iPSC inducers, are highly efficient in generating A549 iPSC-like colonies that have high tumorigenic capacity. To test potential correlation between iPSC inducers and HIF expression in primary tumors, we analyzed primary prostate tumors and found a significant correlation between NANOG-, OCT4-, and HIF1α-positive regions. Furthermore, NANOG and OCT4 expressions positively correlated with increased prostate tumor Gleason score. In primary glioma-derived CD133 negative cells, hypoxia was able to induce neurospheres and hESC markers. Together, these findings suggest that HIF targets may act as key inducers of a dynamic state of stemness in pathologic conditions. Cancer Res; 71(13); 4640–52. ©2011 AACR.

microRNAs (miRNAs) regulate numerous physiological processes such as cell division and differentiation in many tissue types including stem cells. To probe the role that miRNAs play in regulating processes relevant to embryonic stem cell biology, we used RNA interference to silence DICER and DROSHA, the two main miRNA processing enzymes. Consistent with a role for miRNAs in maintaining normal stem cell division and renewal, we found that perturbation of miRNA pathway function in human embryonic stem cells (hESCs) attenuates cell proliferation. Normal cell growth can be partially restored by introduction of the mature miRNAs miR-195 and miR-372. These miRNAs regulate two tumor suppressor genes, respectively: WEE1, which encodes a negative G2/M kinase modulator of the CycB/CDK complex and CDKN1A, which encodes p21, a CycE/CDK cyclin dependent kinase inhibitor that regulates the G1/S transition. We show that in wild-type hESCs, WEE 1 levels control the rate of hESC division, whereas p21 levels must be maintained at a low level for hESC division to proceed. These data support a model for hESC cell cycle control in which miRNAs regulate negative cell cycle modulators at two phases of the cell cycle to ensure proper replenishment of the stem cell population.

We developed an isotope (87Sr/86Sr, δ18O) reference section for the uppermost Oligocene to lower upper Miocene (ca. 25–8 Ma) at Site 608 in the northeastern North Atlantic. This site contains the least ambiguous magnetostratigraphic record of Miocene polarity changes available, providing direct correlations to the Geomagnetic Polarity Time Scale (GPTS). We integrate biostratigraphic, magnetostratigraphic, Sr isotope, and stable isotope data to provide a reference section for Miocene isotope fluctuations. The direct correlation of isotopes and biostratigraphy to the Geomagnetic Polarity Time Scale (GPTS) provides relatively precise age estimates. We use these age estimates to evaluate the timing of first and last occurrences of planktonic foraminifera, and conclude that many of these are synchronous within a 0.5 m.y. resolution between subtropical Site 563 (33°N) and high-latitude Site 608 (43°N). In addition, we use this chronology to estimate the ages of previously established Miocene oxygen isotope Zones Mi 1 through Mi 7 and to compare the Sr isotope record at Site 608 with previously published 87Sr/86Sr records. We approximate latest Oligocene to early late Miocene (25–8 Ma) Sr isotope changes with two linear regressions. The rate of increase of 87Sr/86Sr was high from the latest Oligocene (∼25 Ma) to earliest middle Miocene (∼15 Ma), with an estimated rate of 0.000059/m.y. Our ability to reproduce Sr isotope measurements is ±0.000030 or better, yielding a stratigraphic resolution of as good as ±0.5 m.y. for this interval. The rate of change was much lower from about 15 to 8 Ma (on average, 0.000013/m.y.), yielding Sr isotope stratigraphic resolution of worse than ±2.3 m.y. The causes of the late Eocene to Miocene 87Sr/86Sr increases are not known. We speculate that a moderate 87Sr/86Sr increase (0.000030/m.y) which occurred during the late Eocene-latest Oligocene can be explained by intermittent glaciations and deglaciations of the Antarctic continent. These pulse-like changes in the input of glacial weathering products yield what appears to be a monotonic, linear increase. The increase in the frequency of glaciations during the latest Oligocene-early Miocene can explain the higher rate of change of 87Sr/86Sr at this time. We speculate that by the middle Miocene, the development of a permanent east Antarctica ice sheet resulted in decreased input of glacial weathering products and a lower rate of 87Sr/86Sr change. Appendix 1 is available with entire article on microfiche.Order from American Geophysical Union, 2000 FloridaAvenue N.W., Washington, D.C. 20009. Document P90-001;$2.50. Payment must accompany order.

The stringent regulation of cell cycle progression helps to maintain genetic stability in cells. MicroRNAs (miRNAs) are critical regulators of gene expression in diverse cellular pathways, including developmental patterning, hematopoietic differentiation and antiviral defense. Here, we show that two c-Myc-regulated miRNAs, miR-17 and miR-20a, govern the transition through G1 in normal diploid human cells. Inhibition of these miRNAs leads to a G1 checkpoint due to an accumulation of DNA double-strand breaks, resulting from premature temporal accumulation of the E2F1 transcription factor. Surprisingly, gross changes in E2F1 levels were not required to initiate the DNA damage response and checkpoint, as these responses could occur with a less than twofold change in E2F1 protein levels. Instead, our findings indicate that the precise timing of E2F1 expression dictates S-phase entry and that accurate timing of E2F1 accumulation requires converging signals from the Rb/E2F pathway and the c-Myc-regulated miR-17 and miR-20a miRNAs to circumvent a G1 checkpoint arising from the untimely accumulation of E2F1. These data provide a mechanistic view of miRNA-based regulation of E2F1 in the context of the emerging model that miRNAs coordinate the timing of cell cycle progression.

Light-trap and soil-sampling studies were conducted at higher elevations in the Appalachian Mountains of northwestern North Carolina to determine adult flight patterns and white grub population densities and instar ratios of three scarab species: Phyllophaga anxia (LeConte) Glasgow, P. fusca (Froelich) Glasgow, and Polyphylla comes Casey. Flights of the two Phyllophaga species overlapped (May–June), preceding Polyphlla flights (July–August). Multiple flights of Phyllophaga anxia and P. fusca occurred over periods of 10 and 12 weeks, respectively. Multiple flights of Polyphylla comes lasted for 6 weeks. For all three species, peak flight densities occurred 3 to 4 weeks after initial flights. Phyllophaga males and females were captured in large numbers, but very few female Polyphylla were caught. Most Phyllophaga were caught before midnight, most Polyphylla between midnight and 0400 h. White grubs were found in the root zone from early May to late September. The mean (±SEM) and maximum grub densities observed were 14.6 ± 1.7 and 34.0 grubs per m2, respectively.

Objective To determine the effects of rolipram, a specific type IV phosphodiesterase inhibitor, on tumor necrosis factor (TNF)-alpha production and HIV-1 replication. Design TNF-alpha enhances HIV-1 replication in vitro; blocking TNF-alpha and thereby inhibiting HIV-1 replication may therefore potentially delay progression of HIV disease. Pentoxifylline is a non-specific phosphodiesterase inhibitor that blocks TNF-alpha synthesis and HIV-1 replication in vitro and has been shown in preliminary clinical studies to decrease viral replication in HIV-1-infected patients. Rolipram, which selectively inhibits the predominant phosphodiesterase isoenzyme of monocytes, inhibits lipopolysaccharide (LPS)-induced TNF-alpha with 500-fold greater potency than pentoxifylline. We, therefore, hypothesized that rolipram would be a powerful inhibitor of HIV-1 replication. Methods The effects of rolipram and pentoxifylline on TNF-alpha production and HIV-1 replication were determined in infected and uninfected peripheral blood mononuclear cells (PBMC), in a chronically infected promonocytic cell line (U1) and in an acutely infected monocytic cell line (BT4A3.5). TNF-alpha was determined by specific radioimmunoassay and HIV-1 replication was measured by p24 antigen and HIV-1 mRNA production. Results Rolipram inhibited TNF-alpha production in LPS- and phorbol myristate acetate (PMA)-stimulated PBMC and in PMA-stimulated U1 cells. Rolipram also inhibited HIV-1 replication in the U1 cell line, as well as in acutely infected PBMC and BT4A3.5 cells. Depending on the experimental conditions, rolipram was 10-600 times more potent, on a molar basis, than pentoxifylline. Conclusion Rolipram is a potent inhibitor HIV-1 replication and therefore deserves further investigation as a potential therapeutic agent in the treatment of HIV-1-infected patients.

The adaptive response of Escherichia coli protects the cells against the toxic and mutagenic effects of certain alkylating agents. The major effector molecule regulating this response is the 39-kDa Ada protein, which functions as both a DNA repair protein and a transcriptional activator. Ada removes methyl groups from phosphotriester and O6-methylguanine lesions in DNA, irreversibly transferring them to cysteine residues at positions 69 and 321, respectively. When methylated at Cys-69, Ada is converted into a potent activator of ada and alkA transcription and binds to a sequence (Ada box) present in both promoters. We have found that physiologically relevant higher concentrations of unmethylated Ada are able to inhibit the activation of ada transcription by methylated Ada, both in vitro and in vivo. In contrast, the same concentrations of unmethylated Ada do not inhibit the activation of alkA transcription by methylated Ada, either in vitro or in vivo. Deletion of the carboxyl-terminal 67 amino acids of Ada abolished the ability of the unmethylated form of the protein to inhibit activation of ada transcription but not the ability of the methylated form to activate ada or alkA transcription. Our results suggest that the Ada protein plays a pivotal role in the negative modulation of its own synthesis and therefore in the down-regulation of the adaptive response. Elements present in the carboxyl terminus of Ada appear to be necessary for this negative regulatory function.

A field experiment was conducted in 1984 and 1985 to evaluate the effects of four weed control practices on white grub densities and feeding damage to roots of young Fraser fir, Abies fraseri (Pursh) Poir., Christmas trees. Variations in wood volume and health were also evaluated. The white grub complex consisted primarily of three species: Phyllophaga anxia (LeConte) Glasgow, Phyllophaga fusca (Froelich) Glasgow, and Polyphylla comes Casey. Cultivation practices were: entire-plot herbicide, not mowed; 0.6-m-wide herbicide-treated strip in tree rows only, mowed; sod, mowed, no herbicide; and sod, not mowed, no herbicide. Mowed sod plots supported the densest grub populations ( x = 44.3 grubs per m2) and contained trees with the most severe root damage, lowest wood volume, and poorest health. Plots treated entirely and in strips with herbicide contained the healthiest, least damaged trees with the highest wood volumes, while supporting mean grub densities of 13.9 and 21.9 grubs per m2, respectively. Grubs in herbicide-strip plots were usually found in the mowed, grassy areas. Plots that were not mowed supported a mean density of 18.5 grubs per m2, and contained trees with moderate to heavy root damage.

A field experiment was conducted during 1984–85 to evaluate the influence of six ground covers on white grub (Coleoptera: Scarabaeidae) densities and feeding damage to roots of young Fraser fir ( Abies fraseri (Pursh) Poir.) Christmas trees in the southern Appalachians. The three dominant grub species were Phyllophaga anxia (LeConte) Glasgow, Phyllophaga fusca (Froelich) Glasgow, and Polyphylla comes Casey. Ground covers were fescue ( Festuca elatior L. cv. Kentucky-31), orchardgrass ( Dactylis glomerata L.), Kentucky bluegrass ( Poa pratensis L.), red clover ( Trifolium pratense L.), subterranean clover ( Trifolium subterraneum L. cv. Mt. Barker), and dead sod–entire plot herbicide. Mowed grass plots supported the densest grub populations ($\bar x$ = 32.3 to 43.0 grubs per m2) when compared with clover and dead sod plots ( x ¯ = 13.3 to 16.1 grubs per m2), and contained fir trees with the most severe feeding damage to roots, poorest health, and lowest wood volumes.

An isogenic set of DNA repair-proficient and -deficient strains of B. subtilis, cured of all prophages, were constructed and analyzed for their sensitivities to selected mutagens. The results demonstrated that the lethal damage caused by ultraviolet (UV) radiation and by 4-nitroquinoline-1-oxide (4NQO) were repaired by the bacterial excision and/or recombination repair systems. In contrast, the lethal damages caused by ethyl methane sulfonate (EMS) and methyl methane sulfonate (MMS) were removed from the DNA by the recombination repair system of the bacteria, and not by the excision repair system. Significantly, the bacteria required both a functional recombination repair system and a functional excision repair system in order to remove the DNA damage caused by the bifunctional alkylating agent mitomycin C (MC).

Field experiments were conducted in 1982, 1983, and 1984 to evaluate the efficacy of several insecticides for controlling white grubs infesting Fraser fir, Abies fraseri (Pursh) Poir., Christmas trees and pastureland scheduled for fir plantings, and to evaluate insecticide phytotoxicity. The white grub complex consisted primarily of three species: Pyllophaga anxia (LeConte) Glasgow, P. fusca (Froelich) Glasgow, and Polyphylla comes Casey. Mean pretreatment white grub population densities ranged from 20.8 to 77.8 grubs per m2. Isazophos, diazinon, carbofuran, carbaryl, trichlorfon, chlorpyrifos, and isofenphos demonstrated a wide range of effectiveness in reducing populations while showing no phytotoxicity to grass sod or fir. Isazophos and diazinon applications provided the highest levels of control.

Laboratory and field tests were conducted from 1983 to 1985 to evaluate the effectiveness of three entomogenous nematodes in reducing white grub populations infesting grass pasture land scheduled for Christmas tree planting. Nematodes tested were three strains of Steinernema feltiae Filipjev (DD-136, Mexican, and All), Steinernema glaseri (Steiner), and Heterorhabditis heliothidis (Khan, Brooks, and Hirschmann). The white grub complex consisted of three species: Phyllophaga anxia (LeConte), Phyllophaga fusca (Froelich), and Polyphylla comes Casey. In laboratory tests, the different nematode species demonstrated similar virulence, producing grub mortalities of 60-80% in 2-4 d. Field treatment results were highly variable; significant grub population reductions occurred at several treatment rates. Sprays with All strain caused the most consistent grub reductions. Nematodes dispersed through the soil to locate and parasitize white grubs. The highest treatment rates usually did not produce the most significant grub population reductions. Rates ranged from 0.54 to 10.76 x 105 nematodes per m2.

Leg 94 of the Deep Sea Drilling Project has provided a unique set of paleomagnetically dated cores, taken along a N-S transect in the North Atlantic. High deposition rates in the sediments, combined with the palaeomagnetic ages, have enabled existing planktonic foraminiferal zonations to be tested and a new zonation for the mid- to high latitudes to be erected. The PL zonation of Berggren (1973, 1977) is shown to be adequate as far north as 41°N, although both the LAD's ofGlobigerina nepenthes andGloborotalia margaritae occur earlier than in tropical regions. North of 41°N these two species have very diachronous LAD's, even though they are common during their range in the northern sites. The new zonation for the mid to high latitude North Atlantic is based on the FAD ofG. margaritae, FAD ofG. puncticulata, LAD ofG. cf. crassula, LAD ofN. atlantica, FAD ofG. inflata and FAD of sinistrally coiled encrustedN. pachyderma.

Largemouth bass ( Micropterus salmoides ), when starved for 1 day, almost totally abstain from eating toad ( Bufo americanus and Bufo woodhousei ) tadpoles. However, there is a positive relationship between bass hunger levels and the acceptability of Bufo larvae as food items. With experience, there is a decrease in the number of toad tadpoles engulfed (taken into the mouth), and that actually consumed by the bass, while the number of larvae expelled (spat out) increases. Bass strongly prefer Hyla crucifer tadpoles to B. americanus larvae, and learn to distinguish between the two species. These results agree with the hypothesis that the schooling behaviour found in B. americanus tadpoles functions, at least in part, as a deterrent to predation.

Stem cells and RNA silencing have emerged as areas of intense interest for both basic and clinical research. Recently these fields have converged with reports implicating small regulatory RNAs in the maintenance and pluripotency of stem cells.

A study was conducted in July and August to compare the efficacy of 3 formulations of Zectran mexacarbate insecticide for balsam woolly adelgid (BWA) control. Pydrin insecticide was used as a comparison standard. A Fraser fir Christmas tree plantation near Cullowhee in Jackson County, N.C., was selected as the study site. A 2.5-gal hand-pressurized portable sprayer was used to spray insecticide treatments on the entire main stem of BWA-infested fir trees (6-7 ft tall) until runoff. Control trees received water sprays only. Eighteen to 20 trees could be sprayed per gal. Treatments were replicated 3 or 4 times, depending on availability of infested trees (1 tree/replicate) and applied in a completely random design. Pretreatment counts were taken on 2 Jul using a no. 8 cork borer to remove 2 heavily BWA infested circular disks of bark from the bole of each tree. All BWA life stages were counted on both disks and added for a total live sample count. In the same manner, posttreatment counts were taken at 2 and 6 wk ifter treatment and compared to corresponding pretreatment counts to determine % live BWA density changes.