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1.
Science ; 371(6533): 1038-1041, 2021 03 05.
Article in English | MEDLINE | ID: mdl-33674491

ABSTRACT

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

2.
Heredity (Edinb) ; 122(4): 441-457, 2019 04.
Article in English | MEDLINE | ID: mdl-30171190

ABSTRACT

In wide-ranging taxa with historically dynamic ranges, past allopatric isolation and range expansion can both influence the current structure of genetic diversity. Considering alternate historical scenarios involving expansion from either a single refugium or from multiple refugia can be useful in differentiating the effects of isolation and expansion. Here, we examined patterns of genetic variability in the trans-continentally distributed painted turtle (Chrysemys picta). We utilized an existing phylogeographic dataset for the mitochondrial control region and generated additional data from nine populations for the mitochondrial control region (n = 302) and for eleven nuclear microsatellite loci (n = 247). We created a present-day ecological niche model (ENM) for C. picta and hindcast this model to three reconstructions of historical climate to define three potential scenarios with one, two, or three refugia. Finally, we employed spatially-explicit coalescent simulations and an approximate Bayesian computation (ABC) framework to test which scenario best fit the observed genetic data. Simulations indicated that phylogeographic and multilocus population-level sampling both could differentiate among refugial scenarios, although inferences made using mitochondrial data were less accurate when a longer coalescence time was assumed. Furthermore, all empirical genetic datasets were most consistent with expansion from a single refugium based on ABC. Our results indicate a stronger role for post-glacial range expansion, rather than isolation in allopatric refugia followed by range expansion, in structuring diversity in this species. To distinguish among complex historical scenarios, we recommend explicitly modeling the effects of range expansion and evaluating alternate refugial scenarios for wide-ranging taxa.


Subject(s)
Genetic Speciation , Genetic Variation , Turtles/genetics , Animals , Bayes Theorem , Climate Change , DNA, Mitochondrial/genetics , Demography , Ecosystem , Genetics, Population , Microsatellite Repeats/genetics , Models, Biological , Phylogeography , Refugium , Turtles/classification
3.
Cancer Res ; 60(2): 328-33, 2000 Jan 15.
Article in English | MEDLINE | ID: mdl-10667584

ABSTRACT

Most cytotoxic anticancer agents damage DNA directly, interfere with DNA metabolism or chromosome segregation, and are particularly toxic in dividing cells. Although a considerable amount of information on the mechanisms of action of these agents is available, the molecular bases for selective tumor cell killing by chemotherapy are largely unknown. Many genetic alterations found in sporadic and hereditary cancers affect functions in DNA repair and cell cycle control and result in sensitivity to DNA damaging agents. We have therefore set out to determine the effects of these cancer mutations on sensitivity or resistance to various chemotherapeutic agents. Because most of the affected genes are well conserved among eukaryotes, we have carried out a comprehensive analysis of a panel of isogenic yeast strains, each defective in a particular DNA repair or cell cycle checkpoint function, for sensitivity to the Food and Drug Administration-approved cytotoxic anticancer agents. Widely different toxicity profiles were observed for 23 agents and X-rays, indicating that the type of DNA repair and cell cycle checkpoint mutations in individual tumors could strongly influence the outcome of a particular chemotherapeutic regimen.


Subject(s)
Antineoplastic Agents/pharmacology , DNA Repair/drug effects , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/genetics , Antimetabolites, Antineoplastic/pharmacology , Cell Cycle/drug effects , Cell Cycle/radiation effects , DNA Damage , DNA Repair/radiation effects , Drug Screening Assays, Antitumor , Humans , Saccharomyces cerevisiae/radiation effects , United States , United States Food and Drug Administration , X-Rays
4.
Exp Neurol ; 135(2): 83-92, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7589327

ABSTRACT

Anterior cingulate cortex (ACC) has one of the highest densities of opioid receptors in the CNS and it has been implicated in acute and chronic pain responses. Little is known, however, about which neurons express opioid receptors in their dendrites and axon terminals. The present studies employed experimental techniques to remove afferent axons or classes of projection neurons from rat ACC area 24 followed by coverslip autoradiography to localize changes in binding of [3H]Tyr-D-Ala-Gly-MePhe-Gly-ol (DAMGO) to mu receptors and 2-[3H]D-penicillamine-5-D-penicillamine-enkephalin (DPDPE) to delta receptors. Removal of all afferents to area 24 with undercut lesions did not alter DPDPE binding, but significantly reduced binding of DAMGO in layers I, III, and V. In contrast, removal of all cortical neurons with the excitotoxin ibotenic acid almost abolished DPDPE binding in all layers. The same lesions reduced DAMGO binding in most layers; however, there was a postlesion bimodal distribution in binding with high levels of binding in layer I and moderate levels in layer VI. These data suggest that delta receptors are expressed by cortical neurons, while mu receptors are expressed by both cortical neurons and afferent axons. To explore the distribution of postsynaptic receptors, immunotoxin lesions were made in area 24 by injection of OX7-saporin into the caudate and/or thalamic nuclei. Almost complete removal of projection neurons to these targets in layers Vb and VIa did not alter DPDPE binding, while the lesions reduced DAMGO binding in all but layer II. Removal of layer Vb corticostriatal projection neurons with caudate OX7-saporin injections reduced binding only in this layer. It is proposed that opioidergic circuits in area 24 are organized according to an input/output model for mu opioid regulation. In this model mu receptors regulate axon terminal activity from the thalamus in layer Ia and the locus coeruleus in layers Ic and II, whereas cortical outputs to the thalamus are modulated via postsynaptic receptors expressed in all layers by thalamocortical projection neurons with somata in layer VI. These opioidergic circuits in ACC are of particular importance because they may regulate responses to chronic nociceptive activity and associated pain perceptions.


Subject(s)
Gyrus Cinguli/drug effects , Neurons/drug effects , Receptors, Opioid, delta/metabolism , Receptors, Opioid, mu/metabolism , Afferent Pathways/physiology , Analgesics/pharmacology , Animals , Binding Sites , Caudate Nucleus/physiology , Enkephalin, D-Penicillamine (2,5)- , Enkephalins/pharmacology , Gyrus Cinguli/metabolism , Male , Models, Neurological , Neurons/physiology , Rats , Rats, Inbred Strains , Receptors, Opioid, delta/drug effects , Receptors, Opioid, mu/drug effects
5.
J Dairy Sci ; 77(9): 2663-70, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7814737

ABSTRACT

Methods were explored for removing within-cow differences between a.m. and p.m. milk yields to allow direct comparison of consecutive milk yields. Daily a.m. to p.m. ratios of milk yield were studied for 504 lactations of 310 Holstein cows. Ratios varied within lactations and among cows. When the incomplete gamma function was used to characterize lactation curves, 89% of the variation in individual milk yields was explained when an a.m.-p.m. term was included. The a.m. to p.m. ratios increased over the course of lactations. Within-cow adjustment factors for a.m.-p.m. milking, based on weighted and unweighted averages of previous a.m. to p.m. ratios, changed as lactation length increased. A weighted moving average technique, which weighted the last a.m. to p.m. ratio by .15, compared with .85 for previous ratios, was considered to be the optimal method of calculating a factor for removing a.m.-p.m. effects.


Subject(s)
Cattle/physiology , Circadian Rhythm , Lactation/physiology , Animals , Female , Genetic Variation , Mathematics , Models, Biological
6.
Ugeskr Laeger ; 156(30): 4343-7, 1994 Jul 25.
Article in Danish | MEDLINE | ID: mdl-8066935

ABSTRACT

Renal insufficiency occurs in 55% of patients with multiple myeloma and is second only to infection as the most common cause of death in these patients. In acute renal failure, improvement can be achieved by correcting fluid balance or hypercalcaemia. Since 1968 chronic dialysis has been recommended as a worthwhile treatment. Haemodialysis and CAPD appear to be equally effective. One year survival in myeloma patients maintained on chronic haemodialysis was 53% while it is reported as 66-76% for myeloma patients not on dialysis. Transplantation may be a treatment option, but only in carefully selected patients. It has been suggested that chronic dialysis should be offered only if there has been a good response to chemotherapy. However, response to chemotherapy and duration of remission are unrelated to renal function and many patients require dialysis before any response to chemotherapy is known. Therefore almost all uraemic myeloma patients should start dialysis initially.


Subject(s)
Acute Kidney Injury/etiology , Kidney Failure, Chronic/etiology , Multiple Myeloma/complications , Acute Kidney Injury/therapy , Humans , Kidney Failure, Chronic/therapy , Kidney Transplantation , Multiple Myeloma/mortality , Multiple Myeloma/physiopathology , Peritoneal Dialysis, Continuous Ambulatory , Prognosis , Renal Dialysis
7.
Ugeskr Laeger ; 154(49): 3512-3, 1992 Nov 30.
Article in Danish | MEDLINE | ID: mdl-1462471

ABSTRACT

A case of severe myelo-meningo-radiculitis with Lyme neuro-borreliosis is described in a patient aged 33 years suffering from insulin dependent diabetes mellitus. It is essential to examine the cerebro-spinal fluid for Borelia burgdorferi specific intrathecal antibody production if sensory radiculitis persist and, finally, if there are focal motor signs and unexplained lymphocytic pleocytosis in the cerebro-spinal fluid. Early diagnosis is very important in order to shorten the course of the illness and recovery.


Subject(s)
Lyme Disease/diagnosis , Meningitis, Bacterial/microbiology , Myelitis/microbiology , Polyradiculoneuropathy/microbiology , Adult , Antibodies, Bacterial/biosynthesis , Borrelia burgdorferi Group/immunology , Diabetes Mellitus, Type 1/complications , Diagnosis, Differential , Humans , Lyme Disease/cerebrospinal fluid , Lyme Disease/immunology , Male , Meningitis, Bacterial/diagnosis , Meningitis, Bacterial/immunology , Myelitis/diagnosis , Myelitis/immunology , Polyradiculoneuropathy/diagnosis , Polyradiculoneuropathy/immunology
8.
Synapse ; 10(1): 44-53, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1311129

ABSTRACT

Ligand binding to many transmitter receptors is much higher in layer Ia of rat posterior cingulate cortex than it is in other layers, and this is where most axons from the anterior thalamus terminate. The present study explores the possibility that a number of receptors may be expressed on axons from limbic thalamic nuclei that terminate in layer Ia. Unilateral thalamic lesions were placed in rats and, 2 weeks later, five ligand binding protocols, coverslip autoradiography, and single grain counting techniques were used to quantify binding in control and ablated hemispheres. Binding to the following receptor subtypes was analyzed: M2 acetylcholine, 3H-oxotremorine-M, or 3H-AF-DX 116 with 50 nM pirenzepine; serotonin1B, 125I-(-)-cyanopindolol with 30 microM isoproterenol; beta 2-adrenoceptors, 125I-(-)-cyanopindolol with 1 microM serotonin and 10 microM atenolol; mu-opioid, 3H-T[r-D-Ala-Gly-MePhe-Gly-ol; neurotensin, 3H-neurotensin. Thalamic lesions reduced binding in two laminar patterns. In one pattern, there was a major reduction in binding in most superficial layers with that in layer Ia ranging from 50 to 70% for binding to M2 muscarinic and serotonin1B receptors. Binding to beta 2-adrenoceptors was also reduced in most superficial layers but to a lesser extent. In the second pattern, reductions were limited to layer I with losses in layer Ia of 20-30% for mu-opioid and neurotensin receptors. In no instance was layer Ia binding completely abolished (i.e., postlesion peaks remained). Since the transmitters for each of the five receptors analyzed in this study are not synthesized by anterior or laterodorsal thalamic neurons, these receptors are heteroreceptors. The greatest postlesion reduction in M2 binding was for AF-DX 116 and so most M2 heteroreceptors are of the "cardiac" subtype. Finally, the diverse population of heteroreceptors on limbic thalamic axons provides for presynaptic modulation by a wide range of transmitter systems and suggests that thalamocortical transmission may not be a simple, unmodulated event.


Subject(s)
Axons/physiology , Limbic System/physiology , Receptors, Adrenergic, beta/metabolism , Receptors, Muscarinic/metabolism , Receptors, Neurotransmitter/metabolism , Receptors, Opioid/metabolism , Receptors, Serotonin/metabolism , Thalamus/physiology , Atenolol/pharmacology , Autoradiography , Axons/drug effects , Enkephalin, Ala(2)-MePhe(4)-Gly(5)- , Enkephalins/metabolism , Ethanolamines/pharmacology , Limbic System/anatomy & histology , Limbic System/drug effects , Neurotensin/metabolism , Oxotremorine/metabolism , Pindolol/analogs & derivatives , Pindolol/metabolism , Pirenzepine/analogs & derivatives , Pirenzepine/metabolism , Receptors, Neurotensin , Receptors, Opioid, mu , Thalamus/anatomy & histology , Thalamus/drug effects , Tritium
9.
J Dairy Sci ; 74(7): 2172-9, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1894813

ABSTRACT

Milk yield data from herds at the University of Illinois and the University of Wisconsin-Madison were used to characterize milk yield fluctuations concurrent with conception. Analyses were performed on 118 Illinois and 244 Wisconsin cows; milk yields were recorded for 15 d preceding confirmed conception. Conception was confirmed by calving within 11 d of 281 d postbreeding. Each cow's difference between 7-d rolling means for a.m. and p.m. milking yield was subtracted from a.m. yields as a diurnal adjustment. A pattern matching formula that was applied to adjusted yields [( b - a]/a, where a and b were sequential milkings) produced a mean calculated value for the milking nearest conception that was different from all milkings for 15 d preceding conception in Wisconsin data only. Discriminant analysis failed to differentiate between preceding and conception inclusive sequences of adjusted milk yields. Pattern matching formulas applied to individual cow data failed to isolate more than 2% of conceptions when the threshold value was set to eliminate false positives. Results demonstrated low predictive ability for conception using concurrent milk yield fluctuations despite implications of significant mean differences for values that were enhanced by pattern matching formulas.


Subject(s)
Cattle/physiology , Estrus/physiology , Fertilization/physiology , Lactation/physiology , Animals , Discriminant Analysis , Female
10.
J Neurosci ; 11(6): 1508-14, 1991 Jun.
Article in English | MEDLINE | ID: mdl-2045875

ABSTRACT

Training-induced neuronal activity develops in the mammalian limbic system during discriminative avoidance conditioning. This study explores behaviorally relevant changes in muscarinic ACh receptor binding in 52 rabbits that were trained to one of five stages of conditioned response acquisition. Sixteen naive and 10 animals yoked to criterion performance served as control cases. Upon reaching a particular stage of training, the brains were removed and autoradiographically assayed for 3H-oxotremorine-M binding with 50 nM pirenzepine (OXO-M/PZ) or for 3H-pirenzepine binding in nine limbic thalamic nuclei and cingulate cortex. Specific OXO-M/PZ binding increased in the parvocellular division of the anterodorsal nucleus early in training when the animals were first exposed to pairing of the conditional and unconditional stimuli. Elevated binding in this nucleus was maintained throughout subsequent training. In the parvocellular division of the anteroventral nucleus (AVp), OXO-M/PZ binding progressively increased throughout training, reached a peak at the criterion stage of performance, and returned to control values during extinction sessions. Peak OXO-M/PZ binding in AVp was significantly elevated over that for cases yoked to criterion performance. In the magnocellular division of the anteroventral nucleus (AVm), OXO-M/PZ binding was elevated only during criterion performance of the task, and it was unaltered in any other limbic thalamic nuclei. Specific OXO-M/PZ binding was also elevated in most layers in rostral area 29c when subjects first performed a significant behavioral discrimination. Training-induced alterations in OXO-M/PZ binding in AVp and layer Ia of area 29c were similar and highly correlated.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Avoidance Learning , Gyrus Cinguli/physiology , Oxotremorine/metabolism , Pirenzepine/metabolism , Receptors, Muscarinic/metabolism , Thalamus/physiology , Animals , Autoradiography , Discrimination, Psychological , Kinetics , Male , Organ Specificity , Pirenzepine/pharmacology , Rabbits , Tritium
11.
J Dairy Sci ; 73(1): 191-7, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2312883

ABSTRACT

Heritabilities and genetic and phenotypic correlations among 14 linear type traits were estimated from Holstein Association data by multiple trait REML. Data used for parameter estimation were records of 779,391 daughters of 871 sires included in the January 1988 sire evaluation. Each daughter was represented by her appraisal closest to 30 mo of age. Highest heritability was .37 for stature, and lowest was .10 for foot angle. Gains in reliability from using correlated traits in multiple trait prediction were large for some traits (up to 60% for foot angle for cows). Final score variance parameters were estimated from 953,596 records, which were 43% of records included in the national sire evaluation. Sire models that adjusted or did not adjust for merit of mates were compared. Heritability of final score was .27 with adjustment for merit of mates by subtraction of predicted transmitting ability of dam from daughter's record compared with .29 if mate was ignored. Evaluations for type for several popular older sires were reduced moderately by adjustment for merit of mates, but estimated genetic trend increased slightly. An improved genetic grouping procedure that considers group effects as inherited was adapted for use in sire models. Parameter estimates and models presented were implemented by the Holstein Association for computing July 1988 genetic evaluations for linear traits and final score.


Subject(s)
Breeding , Cattle/genetics , Models, Genetic , Analysis of Variance , Animals , Female , Male , Phenotype
12.
Acta Radiol ; 28(1): 85-6, 1987.
Article in English | MEDLINE | ID: mdl-2952149

ABSTRACT

Radiologic examination of the feet was performed in 72 normal persons with no history or physical signs of disease of the feet. In about 10 per cent, bilateral flat configuration of the second metatarsal head accompanied by a joint space wider than in the neighbouring joints was found, and is therefore a normal anatomic variant that must not be confused with Freiberg's disease or its final stages.


Subject(s)
Foot Diseases/diagnostic imaging , Metatarsus/diagnostic imaging , Adolescent , Adult , Aged , Diagnosis, Differential , Female , Humans , Male , Metatarsus/anatomy & histology , Middle Aged , Radiography
13.
Am J Prev Med ; 1(1): 51-7, 1985.
Article in English | MEDLINE | ID: mdl-3870895

ABSTRACT

Nitrate contamination of potable water supplies is a recognized health hazard. Potentially, the contamination of private drinking water supplies could be a problem in the rural Palouse area of Idaho and Washington. Studies have shown that 12 percent of the rural population of Whitman County, Washington, may be drinking water containing nitrates in excess of the national standard. Yet there is no organized concern about this potential health hazard among local citizens. After reviewing the literature on nitrate contamination of ground water and discussing nitrate contamination of private potable water supplies in the Palouse, we use a social movement theory of social problems to explain why this situation has not been defined as a public health problem.


Subject(s)
Nitrates/adverse effects , Social Problems , Water Pollution, Chemical , Humans , Idaho , Washington
16.
Biometrics ; 24(3): 517-26, 1968 Sep.
Article in English | MEDLINE | ID: mdl-5686304
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