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1.
Nature ; 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39048015

ABSTRACT

Of the ~25 directly imaged planets to date, all are younger than 500Myr and all but 6 are younger than 100Myr1. Eps Ind A (HD209100, HIP108870) is a K5V star of roughly solar age (recently derived as 3.7-5.7Gyr2 and 3.5 - 1.3 + 0.8 Gyr3). A long-term radial velocity trend 4,5 as well as an astrometric acceleration6,7 led to claims of a giant planet2,8,9 orbiting the nearby star (3.6384±0.0013pc10). Here we report JWST coronagraphic images that reveal a giant exoplanet which is consistent with these radial and astrometric measurements, but inconsistent with the previously claimed planet properties. The new planet has temperature ~275K, and is remarkably bright at 10.65µm and 15.50µm. Non-detections between 3.5-5µm indicate an unknown opacity source in the atmosphere, possibly suggesting a high metallicity, high carbon-to-oxygen ratio planet. The best-fit temperature of the planet is consistent with theoretical thermal evolution models, which are previously untested at this temperature range. The data indicates that this is likely the only giant planet in the system and we therefore refer to it as "b", despite it having significantly different orbital properties than the previously claimed planet "b".

2.
Nutr Res Rev ; 11(1): 133-68, 1998 Jun.
Article in English | MEDLINE | ID: mdl-19087463

ABSTRACT

Anaerobic chytridiomycete fungi are found in the gastrointestinal tracts of sheep, cattle and goats, as well as in many other domesticated ruminant and nonruminant herbivores and a wide variety of wild herbivorous mammals. They are principally found associated with the fibrous plant particles of digesta and as free swimming zoospores in the fluid phase. The presence of large fungal populations in animals consuming mature pasture or diets largely composed of hay or straw together with the production of highly active fibre degrading enzymes lead to' the belief that anaerobic fungi may have a significant role to play in the assimilation of fibrous feeds by ruminants. While many early studies focused on anaerobic fungi because of their unusual biology and metabolism, the large part of subsequent research has emphasized the biotechnological potential of their cellulases, xylanases and phenolic esterases. In recent years, the extent of the contribution of anaerobic fungi to the nutrition of ruminants has also been established through studies of fungal populations in the rumen and the dietary factors which influence them, as presented in this review. Further, we discuss the evidence supporting an important contribution of anaerobic fungal populations in the rumen to feed intake and digestion of poor quality feed by domesticated ruminants. In conclusion, the review explores some different methods for manipulating fungi in the rumen for increased feed intake and digestion.

3.
Biologicals ; 24(3): 243-53, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8978924

ABSTRACT

The verification of membrane integrity for filtration processes specifically designed for the removal of adventitious virus from biotherapeutics is of the utmost importance to both biomanufacturers and regulatory agencies. Although conventional bubble-point and air-diffusion tests are widely accepted for integrity testing of bacteria-retentive membranes, these tests have severe limitations in their ability to assess the integrity of virus-retentive membranes. A novel membrane integrity test based upon liquid-liquid porosimetric principles (CorrTest) has been specifically designed to correlate and predict the virus retention capabilities of Viresolve virus removing membranes. To optimize test sensitivity for both Viresolve/70 and Viresolve/180 membrane types, two distinct porosimetric correlations at different transmembrane pressures have been developed. Based upon an 80% prediction interval, an integrity test performed at either test pressure can reliably predict the ability of Viresolve membranes to remove the bacteriophage phi X174 to within 0.4 log removal value (LRV) units. To maintain test sensitivity and provide greater flexibility for conducting the liquid-liquid intrusion integrity test, appropriate pressure- and temperature-correction equations have been established. The two immiscible fluids employed in the developed technology are easily flushed from the membrane structure and are generally regarded as acceptable, non-toxic reagents for pharmaceutical applications. Consequently, the CorrTest integrity test can reliably and non-destructively measure both pre- and post-use membrane integrity to verify virus removal performance with the Viresolve module.


Subject(s)
Bacteriophage phi X 174/isolation & purification , Mathematical Computing , Membranes, Artificial , Reproducibility of Results , Temperature
4.
Anaerobe ; 1(1): 41-7, 1995 Feb.
Article in English | MEDLINE | ID: mdl-16887506

ABSTRACT

Fructose, glucose and xylose were the only monosaccharides to be fermented by the polycentric fungi, Orpinomyces joyonii (three cattle isolates) and O. intercalaris (two cattle isolates) and Anaeromyces spp. (four cattle isolates and two water buffalo isolates). Both Orpinomyces spp. utilised a similar range of oligosaccharides and polysaccharides by fermenting cellobiose, gentiobiose, lactose, maltose, sucrose, cellulose, glycogen, starch and xylan. In contrast, there was considerable variation in carbohydrate fermentation amongst Anaeromyces spp., with only cellobiose, gentiobiose and cellulose being fermented by all strains. Formate, acetate and ethanol were the major fermentation end-products formed from glucose by all polycentric fungi. In addition, Anaeromyces spp. produced considerable amounts of lactate, although only small amounts were formed by Orpinomyces spp. This difference was explained by the low specific activity for lactate dehydrogenase in Orpinomyces spp. Several Anaeromyces spp. also produced malate as a significant end-product of glucose fermentation. Fermentation of specifically-labelled Z14C]glucose molecules by polycentric fungi showed that hexose was catabolised by both polycentric and monocentric fungi via the glycolysis pathway with end-products being derived from the following carbon atoms: lactate and malate (C1-C3; C4-C6), acetate and ethanol (C1-C2; C5-C6), CO2 and formate (C3; C4). The results were compared to those obtained for monocentric and polycentric fungi isolated from temperate climate ruminants.

5.
Opt Lett ; 18(12): 1010-2, 1993 Jun 15.
Article in English | MEDLINE | ID: mdl-19823275

ABSTRACT

A novel technique for measuring the separation of widely spaced optical frequencies is demonstrated. It relies on frequency comb generation by use of a laser that incorporates a frequency-shifting element. A Nd:YLF laser is used to produce a frequency comb that has a bandwidth of 140 GHz and that contains in excess of 875 discrete frequencies, accurately spaced by 160 MHz. The longitudinal mode spacing of a dual-frequency laser was measured to an accuracy of +/-5 kHz in 3,733,440.0 kHz by use of the technique described here.

6.
Lett Appl Microbiol ; 15(3): 116-9, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1368785

ABSTRACT

The ionophore antibiotics monensin and tetronasin have been reported to inhibit anaerobic fungi in vitro, and are suitable for animal use. In this study, their effectiveness in removing the anaerobic fungus Neocallimastix sp. LM1 from the rumen was investigated in vitro. Both antibiotics were fungistatic: tetronasin at 0.5 microgram/ml and monensin at 1.0 microgram/ml; exposure for 24 h did not inhibit subsequent growth after removal of the ionophore. The ionophores were fungicidal at much higher concentrations, 1 microgram/ml for tetronasin and 16 micrograms/ml for monensin. It seems likely that the combination of relatively high inhibitory dose and the fungistatic nature of monensin would explain difficulties in using this compound to eliminate anaerobic fungi from the rumens of experimental animals.


Subject(s)
Antifungal Agents/pharmacology , Fungi/drug effects , Ionophores/pharmacology , Monensin/pharmacology , Rumen/microbiology , Animals , Furans/pharmacology , Sheep
7.
Int J Syst Bacteriol ; 42(1): 27-36, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1736969

ABSTRACT

Helical organisms with novel ultrastructural characteristics were isolated from the intestinal mucosa of rats and mice. These bacteria were characterized by the presence of 9 to 11 periplasmic fibers which appeared as concentric helical ridges on the surface of each cell. The cells were motile with a rapid corkscrewlike motion and had bipolar tufts of 10 to 14 sheathed flagella. The bacteria were microaerophilic, nutritionally fastidious, and physiologically similar to Helicobacter species and Wolinella succinogenes but could be differentiated from these organisms by their unique cellular ultrastructure. Using 16S rRNA sequencing, we found that strain ST1T (T = type strain) was related to previously described Helicobacter species, "Flexispira rappini," and W. succinogenes. The closest relatives of strain ST1T were Helicobacter mustelae and "F. rappini" (average similarity value, 96%). On the basis of phylogenetic data, strain ST1T (= ATCC 49282T) represents a new species of the genus Helicobacter, for which we propose the name Helicobacter muridarum.


Subject(s)
Helicobacter/ultrastructure , Intestinal Mucosa/microbiology , Animals , Base Sequence , Helicobacter/genetics , Helicobacter/metabolism , Mice , RNA, Ribosomal, 16S/chemistry , Rats
9.
Appl Environ Microbiol ; 55(7): 1695-702, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2669633

ABSTRACT

Three morphologically different anaerobic fungi, a Neocallimastix sp. strain (LM-1), a Piromonas sp. strain (SM-1), and a Sphaeromonas sp. strain (NM-1), were isolated from the rumens of sheep. Growth studies were conducted with each isolate in batch cultures by using an anaerobic semidefined medium that lacked ruminal fluid and contained 0.5% cellobiose. Cultures were incubated for periods of up to 10 days, and fungal growth was assessed at regular intervals by dry weight measurements. Samples of fungal biomass were also analyzed for cell-associated protein and, after acid hydrolysis, for chitin as hexosamine. The isolates produced similar yields of dry weight and contained similar amounts of protein. However, strain LM-1 grew at a higher rate and contained less than half the level of chitin compared with the other two isolates. There were high positive correlations between chitin and protein for all three fungi, but comparisons of these parameters with dry weights were affected by the presence of variable amounts of storage carbohydrate. The amount of storage carbohydrate reached maximum levels in strain LM-1 during mid-growth phase and then quickly declined thereafter. When dry weight yields for strain LM-1 were adjusted for changes in storage carbohydrate, high positive correlations were obtained between dry weight and protein or chitin. The storage carbohydrate was probably an alpha-1,4-glucan with alpha-1,6 branches.


Subject(s)
Cellobiose/metabolism , Chytridiomycota/growth & development , Disaccharides/metabolism , Rumen/microbiology , Anaerobiosis , Animals , Carbohydrates/analysis , Chitin/analysis , Chytridiomycota/analysis , Chytridiomycota/classification , Chytridiomycota/metabolism , Culture Media , Fungal Proteins/analysis , Microscopy, Phase-Contrast , Sheep
10.
Appl Environ Microbiol ; 55(7): 1703-10, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2764575

ABSTRACT

Three different ruminal fungi, a Neocallimastix sp. (strain LM-1), a Piromonas sp. (strain SM-1), and a Sphaeromonas sp. (strain NM-1), were grown anaerobically in liquid media which contained a suspension of either 1% (wt/vol) purified cellulose or finely milled wheat straw as the source of fermentable carbon. Fungal biomass was estimated by using cell wall chitin or cellular protein in cellulose cultures and chitin in straw cultures. Both strains LM-1 and SM-1 degraded cellulose with a concomitant increase in fungal biomass. Maximum growth of both fungi occurred after incubation for 4 days, and the final yield of protein was the same for both fungi. Cellulose degradation continued after growth ceased. Strain NM-1 failed to grow in the cellulose medium. All three anaerobic fungi grew in the straw-containing medium, and loss of dry weight from the cultures indicated degradation of straw to various degrees (LM-1 greater than SM-1 greater than NM-1). The total fiber component and the cellulose component of the straw were degraded in similar proportions, but the lignin component remained undegraded by any of the fungi. Maximum growth yield on straw occurred after 4 days for strain LM-1 and after 5 days for strains SM-1 and NM-1. The calculated yield of cellular protein for strain LM-1 was twice that of both strains SM-1 and NM-1. The cellular protein yield of strain SM-1 was the same in both cellulose and straw cultures. In contrast to cellulose, straw degradation ceased after the end of the growth phase.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Animal Feed , Cellulose/metabolism , Chytridiomycota/metabolism , Rumen/microbiology , Anaerobiosis , Animals , Cellobiose/metabolism , Chitin/analysis , Chytridiomycota/analysis , Chytridiomycota/enzymology , Chytridiomycota/growth & development , Culture Media , Fermentation , Fungal Proteins/analysis , Glucose/metabolism , Sheep , Triticum , Xylans/metabolism
11.
Opt Lett ; 14(4): 219-21, 1989 Feb 15.
Article in English | MEDLINE | ID: mdl-19749875

ABSTRACT

Frequency-modulation mode locking of a Nd(3+)-doped fiber laser operating at 1.09 microm using a bulk phase modulator is reported. The resulting pulses have a 20-psec duration (FWHM) and a peak power of 1 W. A least-squares fit to the second-harmonic-intensity autocorrelation trace and the time-bandwidth product of 0.30 +/- 0.04 suggest that the pulses are bandwidth limited with a sech(2)-type profile.

12.
Opt Lett ; 14(13): 680-2, 1989 Jul 01.
Article in English | MEDLINE | ID: mdl-19752934

ABSTRACT

FM mode-locked operation of a single-mode Nd(3+)-doped fiber laser has been achieved with an integrated fiber phase modulator. The technique permits a low-loss cavity configuration, resulting in low threshold and high slope efficiency. Pulses of ~200-psec duration are observed at a repetition rate of 417 MHz with an average output power of 15 mW.

13.
J Chromatogr ; 439(2): 341-51, 1988 May 20.
Article in English | MEDLINE | ID: mdl-3403648

ABSTRACT

Displacement chromatography was used for the preparative-scale separation of peptides, antibiotics, and proteins. The feed components were both purified and concentrated during the separation processes. The components of a peptide mixture were separated on a reverse-phase analytical column using 2-(2-butoxyethoxy) ethanol as the displacer. The use of organic modifiers in the carrier along with an elevated column temperature of 45 degrees C enabled the efficient separation of relatively hydrophobic peptides by displacement chromatography. In addition, the throughput of the process was significantly increased by carrying out the separation at an elevated flow-rate with no adverse effect on product purity. The antibiotic cephalosporin C was isolated from impurities in a fermentation broth using 2-(2-butoxyethoxy)ethanol as the displacer along with a step change in column temperature. The proteins cytochrome c and lysozyme were purified on a weak cation-exchanger column using cationic polymers as the displacers. While polymers of 60 and 20 kilodaltons were both found to be good displacers for these proteins, only the lower molecular weight polymer was readily removed from the column by standard regeneration techniques.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Chromatography, High Pressure Liquid/methods , Peptides/isolation & purification , Proteins/isolation & purification , Cephalosporins/isolation & purification , Spectrophotometry, Ultraviolet , Thermodynamics
14.
Biosystems ; 21(3-4): 377-83, 1988.
Article in English | MEDLINE | ID: mdl-3395691

ABSTRACT

Nine strains of anaerobic fungi, assigned to the genera Neocallimastix and Piromonas, have been isolated from samples of ruminal digesta obtained from sheep and cattle in temperate Australia. Two strains of Sphaeromonas were also isolated from sheep. The patterns of utilization of mono-, oligo- and polysaccharides were determined for these fungi, four Neocallimastix spp. from Britain and New Zealand, and two Piromonas spp. from Britain. All 17 strains utilized cellobiose, fructose, gentiobiose, glucose and lactose. The seven Neocallimastix spp., whether from sheep or cattle, also fermented cellulose, glycogen, inulin, maltose, raffinose, starch, sucrose, xylan and xylose. Both Sphaeromonas isolates also fermented xylan and xylose. The eight Piromonas strains displayed a diversity in carbohydrate utilization, and could not be formed into a cohesive group. The metabolic endproducts of one strain each of Neocallimastix, Sphaeromonas and Piromonas were determined. They all produced acetate, formate, D(-)-lactate, ethanol and CO2 during glucose fermentation.


Subject(s)
Carbohydrate Metabolism , Fungi/metabolism , Polysaccharides/metabolism , Rumen/microbiology , Anaerobiosis , Animals , Australia , Cattle , Fermentation , Fungi/isolation & purification , New Zealand , Sheep , Species Specificity , United Kingdom
15.
Pharmacology ; 36 Suppl 1: 221-5, 1988.
Article in English | MEDLINE | ID: mdl-3368522

ABSTRACT

A HPLC method was developed to measure rhein, a laxatively active metabolite of sennosides A + B, in milk and plasma. Samples from 2 lactating rhesus monkeys were taken over 48 h after oral administration of sennosides (1 mg kg-1). Detectable rhein levels were found in plasma between 2 and 12 h and in milk between 4 and 12 h after administration, but rhein excretion in milk seems to be far below the dose necessary to elicit a laxative effect in the suckling offspring.


Subject(s)
Anthraquinones/pharmacokinetics , Milk/metabolism , Animals , Anthraquinones/administration & dosage , Anthraquinones/blood , Anthraquinones/metabolism , Cathartics/pharmacokinetics , Female , Lactation/metabolism , Macaca mulatta , Pregnancy , Senna Extract , Sennosides
16.
J Biol Chem ; 262(36): 17412-9, 1987 Dec 25.
Article in English | MEDLINE | ID: mdl-3320042

ABSTRACT

Intact cultured human fibroblasts reduced [1-14C]palmitate to radioactive hexadecanol in a concentration-dependent manner. In the presence of 30 microM radioactive palmitate, cellular levels of labeled hexadecanol increased over time and reached a steady state corresponding to at least 0.1% of cell-associated radioactive palmitate. These levels of [14C]hexadecanol were increased up to 10-fold when exogenous nonradioactive hexadecanol was present, suggesting that radioactive hexadecanol was actively metabolized. Cells incubated in fatty acid-free medium with [1-14C]hexadecanol rapidly oxidized it to palmitic acid; less than 2% of the hexadecanol taken up by the cells was incorporated into the ether linkage of phosphatidylethanolamine, and no incorporation into wax esters was detected. Double-label experiments involving incubation of intact fibroblast with [3H]palmitate and [14C]hexadecanol demonstrated simultaneous synthesis of hexadecanol from palmitate and oxidation of hexadecanol to palmitate. Addition of exogenous palmitate to the medium of intact cells inhibited the oxidation of hexadecanol to fatty acid in a concentration-dependent fashion. This was associated with an increase in the fibroblast content of hexadecanol and loss of hexadecanol into the medium. Activity of fatty alcohol:NAD+ oxidoreductase, which catalyzes the oxidation of hexadecanol to palmitic acid, was inhibited by palmitoyl-CoA and NADH, but not by palmitic acid. These results are consistent with the presence of a "fatty alcohol cycle" in which hexadecanol is synthesized from palmitate via acyl-CoA and simultaneously oxidized back to free fatty acid. Fatty acyl-CoA, which is the primary substrate for fatty alcohol synthesis, may also regulate the intracellular level of fatty alcohol by inhibiting its oxidation.


Subject(s)
Fatty Alcohols/metabolism , Fibroblasts/metabolism , Acyl Coenzyme A/metabolism , Alcohol Oxidoreductases/antagonists & inhibitors , Cells, Cultured , Humans , NAD/metabolism , Palmitic Acid , Palmitic Acids/metabolism , Palmitoyl Coenzyme A/pharmacology
17.
Ann Neurol ; 21(3): 232-9, 1987 Mar.
Article in English | MEDLINE | ID: mdl-3037987

ABSTRACT

Adrenoleukodystrophy (ALD) is an X-linked disorder characterized by demyelination, adrenal insufficiency, and accumulation of saturated very-long-chain fatty acids (VLFA), particularly hexacosanoate (C26:0). We treated 5 patients with adrenoleukodystrophy (3 males and 2 symptomatic female carriers) for 6 months with a diet enriched in oleic acid (C18:1) and moderately restricted in C26:0. Elevated plasma and erythrocyte levels of C26:0 decreased in a time-dependent manner during treatment. Total plasma C26:0 concentration was lowered by 50 +/- 9% (p less than 0.01); it became normal in the female carriers. The total erythrocyte level of C26:0 decreased (44 +/- 5%; p less than 0.001) into the normal range in all patients. Significant decreases were noted in the saturated VLFA composition of plasma and erythrocyte sphingomyelin and erythrocyte phosphatidylcholine during dietary treatment. In general, decreases in saturated VLFA levels were accompanied by increases in monounsaturated VLFA levels, while total VLFA values did not change. This novel approach to the treatment of adrenoleukodystrophy, in which there is an exchange of monounsaturated VLFA for the more toxic saturated VLFA, may prove clinically beneficial in this disorder.


Subject(s)
Adrenoleukodystrophy/diet therapy , Dietary Fats/therapeutic use , Diffuse Cerebral Sclerosis of Schilder/diet therapy , Fatty Acids/blood , Oleic Acids/administration & dosage , Peripheral Nervous System Diseases/genetics , Adrenoleukodystrophy/blood , Erythrocytes/analysis , Female , Heterozygote , Humans , Male , Oleic Acid
18.
Neurology ; 36(3): 357-61, 1986 Mar.
Article in English | MEDLINE | ID: mdl-3951702

ABSTRACT

Monounsaturated fatty acids, especially oleic acid (C18:1), decreased the content of saturated very-long-chain fatty acids (VLFA) in cultured skin fibroblasts from patients with adrenoleukodystrophy (ALD) and controls. When confluent ALD fibroblasts were incubated with oleic acid for 5 days in lipid-free medium, which eliminates uptake of exogenous VLFA, the mean cell content of C26:0 was decreased by 33.7 +/- 10.1%. Oleic acid inhibited C26:0 synthesis in ALD fibroblasts by 58% and total fatty acid synthesis by 68 to 78%. Therefore, the elevated C26:0 levels in ALD cells may be lowered by inhibiting fatty acid biosynthesis, and inhibition of saturated VLFA synthesis by oleate may be useful in treating ALD.


Subject(s)
Adrenoleukodystrophy/metabolism , Diffuse Cerebral Sclerosis of Schilder/metabolism , Fatty Acids/metabolism , Fibroblasts/metabolism , Oleic Acids/pharmacology , Animals , Cattle , Cell Line , Female , Humans , In Vitro Techniques , Male , Oleic Acid , Skin/metabolism
19.
Microb Ecol ; 10(1): 79-88, 1984 Mar.
Article in English | MEDLINE | ID: mdl-24221052

ABSTRACT

An allochthonous population of spiral-shaped bacteria was found colonizing the surfaces of the colonic mucosa of rats after they had been given magnesium sulphate (MgSO4)-induced diarrhea. These organisms were rarely seen in normal control rats and were not displaced when the treatment was ceased, remaining associated with the tissue for periods of up to 180 days. Similar bacteria were also found when specific pathogen-free rats, lacking mucosa-associated populations, were inoculated with homogenized rat intestine from conventional animals. Light and electron microscopic observations showed that the organisms were attached to the surface of the colon, orientated at right angles to the tissue, with one end inserted into the microvillus border. This is the first report of long-term colonization, following perturbation of the gut ecosystem, of a site on the gastrointestinal mucosa not normally associated with bacteria. The ultrastructure and mode of attachment of these organisms were very similar to that of spiral-shaped bacteria known to associate with the colonic mucosa in monkeys and man.

20.
Appl Environ Microbiol ; 45(2): 675-83, 1983 Feb.
Article in English | MEDLINE | ID: mdl-6402981

ABSTRACT

Spiral-shaped bacteria with a distinctive morphology were isolated from the intestinal mucosa of rats and mice on a campylobacter selective medium using microaerophilic incubation. These bacteria have been shown by other authors to be present in the intestinal tracts of several animal species but have not been cultured previously. The results of electron microscopic examinations and biochemical testing have shown that these organisms do not correspond to any known genus. Colonization experiments with pure cultures in gnotobiotic rodents have shown these bacteria to be mucosa associated, with a particular affinity for intestinal crypts. The pattern of colonization of the intestinal crypts in gnotobiotes known to be free of other mucosa-associated organisms differed from the colonization occurring in conventional animals that possess a normal mucosa-associated flora.


Subject(s)
Bacteria/isolation & purification , Intestinal Mucosa/microbiology , Animals , Bacteria/cytology , Bacterial Physiological Phenomena , Carbon Dioxide/pharmacology , Cecum/microbiology , Culture Media , Germ-Free Life , Mice , Mice, Inbred BALB C , Rats , Rats, Inbred Strains
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