Basaltic Lava Tube Hosts a Putative Novel Genus in the Family Solirubrobacteraceae.

We report the draft genome sequence of a putative new genus and species, Siliceabacter maunaloa, in the family Solirubrobacteraceae. The members of this family of Actinobacteria are generally Gram positive and mesophilic. Found within a Hawaiian lava tube, this microbe illuminates the types of prokaryotes inhabiting secondary minerals in subsurface basaltic environments.

Metagenome-Assembled Genome of a Putative Chemoheterotroph from Volcanic Terrain in Hawaii.

Here, we present the draft genome for a new putative species, Gaiellasilicea maunaloa, most closely related to Gaiella occulta, within the phylum Actinobacteria. This group contains Gram-negative, aerobic mesophilic species. This metagenome-assembled genome (MAG) contributes to knowledge of life in volcanic environments and may inform investigations of life beyond Earth.

Evidence for a Diagenetic Origin of Vera Rubin Ridge, Gale Crater, Mars: Summary and Synthesis of Curiosity's Exploration Campaign.

This paper provides an overview of the Curiosity rover's exploration at Vera Rubin ridge (VRR) and summarizes the science results. VRR is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mount Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three outcrop samples from the ridge, as well as one outcrop sample immediately below the ridge. Our observations indicate that strata composing VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the orbital spectral detection. Gray hematite is also present in isolated, gray-colored patches concentrated toward the upper elevations of VRR, and these gray patches also contain small, dark Fe-rich nodules. We propose that VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind. Diagenesis also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge, which helped make them readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars' rock record.

Performance of the SAM gas chromatographic columns under simulated flight operating conditions for the analysis of chlorohydrocarbons on Mars.

The Sample Analysis at Mars (SAM) instrument is a gas chromatograph-mass spectrometer onboard the NASA Curiosity rover, currently operating on the surface of Mars. Organic compounds are of major importance with regard to questions of habitability and the potential presence of life on Mars, and one of the mission's main objectives is to analyze the organic content of soil and rock samples. In SAM's first chromatographic measurements, however, unexpected chlorine-bearing organic molecules were detected. These molecules have different origins but the presence of perchlorates and chlorates detected at the surface of Mars suggests that reactivity between organic molecules and thermal decomposition products from oxychlorines is one of the major sources of the chlorinated organic molecules. Here we perform a comprehensive and systematic study of the separation of volatile chlorohydrocarbons with the chromatographic columns used in the SAM instrument. Despite the constrained operating conditions of the flight instrument, we demonstrate that SAM's capillary chromatographic columns allow for effective separation and identification of a wide range of chlorine-bearing species. We also show that instrumental limitations prevent the detection of certain molecules, obscuring our ability to make definitive conclusions about the origin of these organic materials.

Application of TMAH thermochemolysis to the detection of nucleobases: Application to the MOMA and SAM space experiment.

Thermochemolysis of seven nucleobases-adenine, thymine, uracil, cytosine, guanine, xanthine, and hypoxanthine-in tetramethylammonium hydroxide (TMAH) was studied individually by pyrolysis gas chromatography mass spectrometry in the frame of the Mars surface exploration. The analyses were performed under conditions relevant to the Sample Analysis at Mars (SAM) instrument of the Mars Curiosity Rover and the Mars Organic Molecule Analyzer (MOMA) instrument of the ExoMars Rover. The thermochemolysis products of each nucleobase were identified and the reaction mechanisms studied. The thermochemolysis temperature was optimized and the limit of detection and quantification of each nucleobase were also investigated. Results indicate that 600°C is the optimal thermochemolysis temperature for all seven nucleobases. The methylated products trimethyl-adenine, 1, 3-dimethyl-thymine, 1, 3-dimethyl-uracil, trimethyl-cytosine, 1, 3, 7-trimethyl-xanthine (caffeine), and dimethyl-hypoxanthine, respectively, are the most stable forms of adenine, thymine, uracil, cytosine, guanine, and xanthine, and hypoxanthine in TMAH solutions. The limits of detection for adenine, thymine, and uracil were 0.075 nmol; the limits of detection for guanine, cytosine, and hypoxanthine were higher, at 0.40, 0.55, and 0.75 nmol, respectively. These experiments allowed to well constrain the analytical capabilities of the thermochemolysis experiments that will be performed on Mars to detect nucleobases.

The National WIC Evaluation: evaluation of the Special Supplemental Food Program for Women, Infants, and Children. III. Historical study of pregnancy outcomes.

We related perinatal outcome and quality of prenatal care between 1972 and 1980 to WIC benefits to pregnant women among 11,154,673 births in 1392 counties in 19 states and the District of Columbia, adjusted for time change and between-county variability. WIC was associated with increased first trimester prenatal care (4.1%, p less than 0.001), decreased inadequate prenatal care (-5.0%, p less than 0.001), longer duration of gestation (0.20 d, p less than 0.05), decreased preterm delivery (-0.92%, p less than 0.05) and increased birth weight (23 g, p less than 0.01). After autocorrelation was accounted for, significance levels for birth weight and frequency of preterm delivery were 0.05 less than p less than 0.10. Including counties with incomplete time series data, the estimated effect on birth weight was 23.9 g (p = 0.004) and on decreased fetal mortality was -2.3/1000 (p = 0.04). Among those with less than 12 y schooling, whites had a 1.8% reduction in preterm birth (p less than 0.05) and blacks a 2.0% reduction (p less than 0.05). The estimated effect on birth weight for less-educated whites was 46.6 g (p less than 0.001). The predominant effects of WIC were on improved physiologic status of the mother and fetus.

The National WIC Evaluation: evaluation of the Special Supplemental Food Program for Women, Infants, and Children. I. Background and introduction.

The Special Supplemental Food Program for Women, Infants, and Children (WIC) aims to improve the nutrition and health of low-income, nutritionally at-risk pregnant women and preschool children with supplemental food, nutrition education, and coordination of health care. Started in 1972, it recently served greater than 3.4 million persons monthly and at a cost of $1.66 billion annually. The National WIC Evaluation (NWE) consisted of four studies: The historical study estimated changes in birth outcome attributable to WIC from 1972 to 1980 in 19 states and the District of Columbia from WIC program data and vital statistics. The longitudinal study of pregnant women compared dietary intake, weight gain, anthropometry, duration of gestation, birth weight, and infant length and head circumference between a representative national sample of WIC participants and economically comparable women. The cross-sectional study of preschool children related WIC to dietary intake, anthropometry, and psychological development. The food expenditures study estimated the impact of WIC on family grocery and other food expenditures.

The National WIC Evaluation: evaluation of the Special Supplemental Food Program for Women, Infants, and Children. IV. Study methodology and sample characteristics in the longitudinal study of pregnant women, the study of children, and the food expenditures study.

The longitudinal study of pregnant women enrolled a national probability sample of 5,205 women first certified for WIC and 1,358 comparable low-income pregnant women in 174 WIC clinics located in 58 areas in the contiguous 48 states and in 55 prenatal clinics without WIC programs in counties with low program coverage. The women completed 24-h dietary recalls, histories of food expenditures, health care utilization, health and sociodemographic status, and anthropometric assessment. At late-pregnancy follow-up 3,967 WIC and 1043 control women were interviewed and 853 WIC and 762 control women completed 1-wk food expenditure diaries. Birth outcome was abstracted (from hospital records) for 3,863 WIC and 1058 control women. Anthropometry, dietary intake, health, and use of health services were related to WIC among 2,619 random low-income preschoolers. Psychological development was assessed in 526 children aged 4 and 5 y. Control women had higher income, education, and employment status; therefore, WIC program benefits probably were underestimated.

The National WIC Evaluation: evaluation of the Special Supplemental Food Program for Women, Infants, and Children. V. Longitudinal study of pregnant women.

The major associations with the Special Supplemental Food Program for Women, Infants, and Children (WIC) in pregnancy were increased intake of protein, iron, calcium, and vitamin C (four of five targeted nutrients) and of energy, magnesium, phosphorus, thiamin, riboflavin, niacin, vitamin B-6, and vitamin B-12; reversal of low weight gain in early pregnancy; smaller fat stores in late pregnancy; reduced frequency of premature rupture of the uterine membranes; larger infant head circumference with no effect on birth weight and length; increased birth weight and head circumference with better program quality; and lower fetal mortality of appreciable but not significant magnitude. Incremental energy intake was comparable to that in most small-scale supplementation trials. There was no evidence of effects on frequency of prenatal care, use of alcohol or tobacco, the intention to breast-feed, or the rate of breast-feeding. Maternal alcohol intake was associated with depressed infant head circumference, over and above effects on birth weight and length.

The National WIC Evaluation: evaluation of the Special Supplemental Food Program for Women, Infants, and Children. VI. Study of infants and children.

The major associations with the Special Supplemental Food Program for Women, Infants, and Children (WIC) in preschool children were better dietary intake associated with current WIC participation, especially for Fe, vitamin A, and vitamin C, but there were no increases in energy intake and, after infancy, no residual benefits from past WIC participation; strongest dietary effects among children who were poor, black, or in single-parent or large families (children lost to WIC were as needy as those currently enrolled); shorter stature, suggesting effective targeting (with enrollment in utero there was no parallel deficit in head circumference, which is consistent with results for newborns); better immunization and more frequent regular source of health care but no more frequent use of preventive health services; and better vocabulary with WIC participation begun in utero; better digit memory with entry into the program after the first birthday (differences that emerged only after statistical adjustment for sociodemographic factors); and more advantageous child behavior (NS).

Kinetics of expulsion of Haemonchus contortus from sheep and jirds after treatment with closantel.

Experiments were conducted in sheep after intramuscular treatment with closantel and in jirds after oral treatment with closantel to determine when expulsion of established H. contortus commences. Expulsion starts at about 8 h in sheep and coincides with the onset of reduced motility in worms recovered from the abomasum. In jirds, expulsion starts by 2 h after treatment. Experiments also conducted in jirds showed that infective larvae are first killed by circulating closantel 3 days after infection, when blood feeding starts, and that by 8 days 80% of larvae are lost.

Anthelmintic activity of dioxapyrrolomycin.

Dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 produced by UC 11065 were evaluated as anthelmintics. Assays used to examine these compounds included effects on the free-living nematode Caenorhabditis elegans, ability to clear target nematodes (Haemonchus contortus and Trichostrongylus colubriformis) from jirds, and clearance of Haemonchus contortus from lambs. A crude extract of UC 11065 containing dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 was active against C. elegans and against H. contortus in the jird. Purified and/or synthetic samples of dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 were tested in the jird model; only dioxapyrrolomycin exhibited appreciable activity against H. contortus (greater than or equal to 90.9% clearance at 0.33 mg/jird), while none of the compounds showed appreciable activity against T. colubriformis. Dioxapyrrolomycin cleared 99.9% of H. contortus from lambs at 12.5 mg/kg. An in vitro migration study using susceptible and closantel-resistant H. contortus showed there is cross-resistance between dioxapyrrolomycin and closantel. Dioxapyrrolomycin appears to be a narrow-spectrum anthelmintic which works through a closantel-like mode-of-action.

Anthelmintic profile of the cyclodepsipeptide PF1022A in in vitro and in vivo models.

A novel cyclodepsipeptide of fungal origin, PF1022A, recently was reported to have anthelmintic activity. To supplement published reports and determine potential utility of PF1022A as a ruminant anthelmintic, the compound was examined in in vitro and in vivo models. Assays used measured motility of Haemonchus contortus (intrinsic drug potency), ATP levels (parasite death), and activity against H. contortus, Ostertagia ostertagi, and Trichostrongylus colubriformis in the jird (spectrum, potency, and efficacy by various routes). The potency of PF1022A in reducing motility is greater than commercial anthelmintics. Examination of ATP levels in PF1022A-paralyzed H. contortus indicates that worms are not killed, suggesting the compound acts as a neurotoxin in nematodes. In the jird, PF1022A has activity orally against each of the parasites studied and at doses comparable to all commercial anthelmintics, except the macrocyclic lactones which are more potent. Unfortunately, for some nematode species, parenteral delivery is ineffective at realistic doses.

Benzimidazole-resistant beta-tubulin alleles in a population of parasitic nematodes (Cooperia oncophora) of cattle.

Three anthelmintic classes with distinct mechanisms of action are commercially available. Selection of nematode populations resistant to all these drugs has occurred, particularly in trichostrongyloid parasites of sheep. Anthelmintic resistance in cattle parasites has only recently been recognized and appears to be less pronounced, even though very similar species infect both hosts. To understand the bases for differences in the rate of resistance development in sheep versus cattle parasites, it is important to first demonstrate that the same kinds of resistance alleles exist in both. The benzimidazoles (BZ), which have been used for more than 40 years, were chosen as an example. BZ-sensitive (BZ(S)) and BZ-resistant (BZ(R)) nematodes that parasitize sheep have been distinguished at the molecular level by a single nucleotide change in the codon for amino acid 200 of a beta-tubulin gene, a switch from TTC (phenylalanine) to TAC (tyrosine). PCR primers were designed to completely conserved regions of trichostrongyloid beta-tubulin genes and were used to amplify DNA fragments from Haemonchus contortus (cDNA from a BZ(S) and a BZ(R) library) as positive controls. The technique was then extended to the cattle parasites, Cooperia oncophora and Ostertagia ostertagi (from genomic DNA). Sequence analysis proved the presence of amplified BZ(S) alleles in all three species and BZ(R) alleles in the BZ(R) population of H. contortus. Based on these data, nested PCR primers using the diagnostic T or A as the most 3' nucleotide were designed for each species. Conditions for selective PCR were determined. To demonstrate feasibility, genomic DNA was recovered from individual H. contortus L(3) larvae from both BZ(S) and BZ(R) populations. Genomic DNA was also isolated from >70 individual adult male C. oncophora collected from a cattle farm in New Zealand with reported BZ resistance. Allele-specific PCR discriminated among heterozygotes and homozygotes in both species. This method could find utility in studying the molecular epidemiology of BZ resistance in cattle parasites and for defining the variables that limit the development and spread of anthelmintic resistance in this host.

The effects of disposable and custom-made impression trays on the accuracy of impressions.

This study indicates that some non-rigid impression trays, including disposable plastic trays and custom-made acrylic resin trays, may produce unreliable results when used with some medium-bodied elastomers. The study does not question the well-documented clinical accuracy of these elastomers when they are used with rigid trays. Disposable plastic trays are found to be acceptable when used with a combination of reversible and non-reversible hydrocolloid impression materials.

Infectivity of Hymenolepis diminuta for the jird, Meriones unguiculatus, and utility of this model for anthelmintic studies.

The jird (Meriones unguiculatus) has been shown to be a useful model host for the cestodes Taenia crassiceps and Echinococcus multilocularis. This report outlines a novel model in which hydrocortisone-treated jirds (0.02% in the feed) are infected with another cestode, Hymenolepis diminuta. Jirds were inoculated with 5 freshly harvested cysticercoids of H. diminuta prior to (day 0, -1, or -5) or after (day 1 or 5) switching to medicated feed; in some cases, jirds were never medicated. On days 7, 14, 21, or 28 postinoculation (PI), jirds were killed by CO2 inhalation and their small intestines were examined for tapeworms. Hymenolepis diminuta established, grew, and developed to the gravid adult state in jirds. They persisted longer in medicated (21 days) than in nonmedicated (7 days) animals, and generally higher levels of infection were obtained when jirds were inoculated immediately prior to switching to medicated feed. Treatment of infected jirds on day 4 or days 4, 5, and 6 PI with selected anthelmintics followed by necropsy on day 7 PI discriminated drugs with known activity against tapeworms from those with little or no activity. This rodent in vivo model should provide a useful adjunct for anthelmintic studies.

Viability of infective larvae of Haemonchus contortus, Ostertagia ostertagi, and Trichostrongylus colubriformis following exsheathment by various techniques.

Various techniques were examined to determine optimum conditions for exsheathing infective larvae of 3 important ruminant parasites (Haemonchus contortus, Ostertagia ostertagi, and Trichostrongylus colubriformis). In repeated experiments, aliquots of 10(5)-10(6) infective larvae, 1-2 mo old, of each parasite were incubated in each of 4 exsheathing media (distilled water, Earle's balanced salt solution + carbon dioxide, nematode washing buffer + carbon dioxide, or sodium hypochlorite) for 1 or 18 hr. In each case, the percentage of larvae exsheathed and infectivity for jirds was determined. Results of these studies indicate that no single exsheathing technique of those studied is optimum for every parasite. In addition, caution must be used in drawing conclusions from in vitro studies using exsheathed larvae because techniques that routinely provide high percentages of exsheathment also appear to reduce viability.

Prehistoric parasitism in Tennessee: evidence from the analysis of desiccated fecal material collected from Big Bone Cave, Van Buren County, Tennessee.

Eight samples of desiccated human feces collected from Big Bone Cave (40VB103), Van Buren County, Tennessee, were analyzed to determine the presence of ecto- and endoparasitic infection among the prehistoric population using the cave. Radiocarbon-dated torch material from the cave indicated that it was a locus of human activity 2,177 +/- 145 yr ago. Parasitic species identified were: Ascaris lumbricoides, Enterobius vermicularis, fleas of the tribe Phalacropsyllini, and protozoan cysts. The cysts were identified as Giardia using an indirect immunofluorescent antibody test. The only report of Giardia in a prehistoric context is the identification of cysts in 2 1,800-yr-old paleofecal specimens from a cave in Israel. This is the first report of Giardia from paleofeces in the New World.

Prevalence of Toxoplasma gondii antibodies in nine populations of dairy goats: compared titers using modified direct agglutination and indirect hemagglutination.

In a convenience survey of dairy goats on 9 farms in Tennessee, Kentucky, and Georgia, 54 of 99 females were positive for antibodies to Toxoplasma gondii as measured by the indirect hemagglutination test (IHA). Two of 9 males were also positive. Positive goats were found on all farms. The percentage of positive does increased from 55% to 65% when the sera were titered a second time by modified direct agglutination (MDAT). This difference was not statistically significant, indicating that both IHA and MDAT are reliable epidemiological tools.

A coprological survey of parasites of wild neotropical felidae.

In conjunction with an ecological study of jaguars in the Cockscomb Basin of Belize, Central America, fecal samples from jaguars (Panthera onca), jaguarundis (Felis yagouaroundi), ocelots (Felix pardalis), and pumas (Felix concolor) were examined for parasite products (eggs, larvae, and oocysts). Of the 45 samples examined, 39 (86.7%) were positive for parasite products, 23 of 25 (92%) jaguar samples were positive, as were all of the puma (4/4) and ocelot (8/8) samples. Four of 6 samples from unknown species were positive (66.7%). Two jaguarundis samples were negative. The following were identified in the samples: Paragonimus sp. eggs, Taeniidae eggs, Strongylate eggs, Toxocara cati eggs, Toxascaris sp. eggs, Capillaria sp. eggs, Spiruridae eggs, Aelurostrongylus sp. larvae, Oncicola sp. eggs, Hammondia pardalis oocysts, Isospora sp. oocysts, Toxoplasma gondii-like oocysts and Sarcocystis sp. sporocyst.