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1.
MycoKeys ; 60: 125-140, 2019.
Article in English | MEDLINE | ID: mdl-31844414

ABSTRACT

The species of Massalongia recorded and described from the Southern Hemisphere are revised and it is shown that only one is present; M. patagonica which is widespread, with populations in Australia and New Zealand that differ from the South American populations, but at present best regarded as part of the variation of that species. Records from this hemisphere of all other species placed in the genus are incorrect. The type species, M. carnosa, is restricted to the Northern Hemisphere. Two species, M. antarctica and M. novozelandica cannot be identified precisely due to lack of sufficient type material and with the types as the only collections known of these, but none belongs in Massalongia according to available data. Massalongia griseolobata (from Gough Isl.) is shown here to belong in the Pannariaceae and is part of the parmelielloid clade. M. intricata (from South Georgia) and M. olechiana (from South Shetland) have both recently been correctly transferred to the genus Steinera in the Arctomiaceae.

2.
J Endocr Soc ; 1(5): 538-552, 2017 May 01.
Article in English | MEDLINE | ID: mdl-29264508

ABSTRACT

CONTEXT: Peripubertal hyperandrogenemia-a precursor to polycystic ovary syndrome-is prominent in girls with obesity. OBJECTIVE: We examined sources of overnight testosterone (T) and progesterone (P4) and potential sources of obesity-associated hyperandrogenemia during puberty. DESIGN: Cross-sectional. SETTING: Research unit. PARTICIPANTS/INTERVENTIONS: Fifty girls ages 7 to 18 years-both normal weight (NW) and overweight (OW)-underwent dexamethasone (DEX) suppression (1 mg orally; 10 pm) and cosyntropin stimulation testing (0.25 mg intravenously; 8 am the following day), with blood sampled before and 30 and 60 minutes after cosyntropin. Thirty-nine subjects receiving DEX had frequent blood sampling overnight (every 10 minutes from 10 pm to 7 am) and were compared with 70 historical controls who did not receive DEX. OUTCOMES: Random coefficient regression modeling assessed changes in hormone concentrations after DEX and cosyntropin. RESULTS: NW early pubertal controls exhibited early morning increases in free T and P4 levels; NW and OW late pubertal controls exhibited early morning increases in P4. Such changes were not observed in subjects receiving DEX. Post-DEX morning free T levels were fourfold higher in OW vs NW late pubertal girls. Postcosyntropin changes in free T and androstenedione were both 2.3-fold higher in OW vs NW late pubertal girls. CONCLUSIONS: These data suggest that (1) overnight increases in free T and P4 concentrations in NW early pubertal girls and P4 concentrations in late pubertal girls are of adrenal origin and (2) OW late pubertal girls demonstrate elevated nonadrenal free T levels after DEX and exaggerated adrenal androgen (free T and androstenedione) responses to cosyntropin.

3.
Protist ; 168(4): 425-438, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28803921

ABSTRACT

The knowledge of the taxonomy and classification of algae (including lichenized) has recently increased rapidly, but there are still many gaps. We aimed to 1) identify the Fuscidea photobionts by locating their taxonomic positions in the green algal classification, and 2) to resolve their interspecific relationships. The lichenized algae were examined based on morphological observations of axenic isolates as well as molecular studies of 18S and ITS nrDNA sequences. Analysis of the secondary structure of the ITS2 operon complemented these investigations. We found that the Fuscidea photobionts were placed within the Trebouxiophyceae, related to Apatococcus lobatus (Chodat) J.B.Petersen. Phylogenetic analyses revealed one clade nesting free-living and lichenized Apatococcus F.Brand which comprised six different lineages in the ITS phylogeny. The lichenized alga associated with the investigated Fuscidea species, except for F. lightfootii (Sm.) Coppins & James, represents a hitherto unknown lineage within Apatococcus. Fuscidea lightfootii was lichenized with a separate lineage within Apatococcus, together with free-living members, which were already known from Genbank sequences. All retrieved groups within Apatococcus were rather different in their ITS sequences, thus most likely corresponding to different species. The most common photobiont of Fuscidea species, Apatococcus fuscideae A.Beck & Zahradn., was described as new to science.


Subject(s)
Ascomycota/physiology , Chlorophyta/physiology , Symbiosis , Chlorophyta/classification , Chlorophyta/genetics , DNA, Ribosomal Spacer/genetics , Lichens/physiology , Phylogeny , RNA, Algal/genetics , RNA, Ribosomal, 18S/genetics , Sequence Analysis, RNA
4.
Syst Biol ; 57(1): 141-56, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18300027

ABSTRACT

Ancestral state reconstructions of morphological or ecological traits on molecular phylogenies are becoming increasingly frequent. They rely on constancy of character state change rates over trees, a correlation between neutral genetic change and phenotypic change, as well as on adequate likelihood models and (for Bayesian methods) prior distributions. This investigation explored the outcomes of a variety of methods for reconstructing discrete ancestral state in the ascus apex of the Lecanorales, a group containing the majority of lichen-forming ascomycetes. Evolution of this character complex has been highly controversial in lichen systematics for more than two decades. The phylogeny was estimated using Bayesian Markov chain Monte Carlo inference on DNA sequence alignments of three genes (small subunit of the mitochondrial rDNA, large subunit of the nuclear rDNA, and largest subunit of RNA polymerase II). We designed a novel method for assessing the suitable number of discrete gamma categories, which relies on the effect on phylogeny estimates rather than on likelihoods. Ancestral state reconstructions were performed using maximum parsimony and maximum likelihood on a posterior tree sample as well as two fully Bayesian methods. Resulting reconstructions were often strikingly different depending on the method used; different methods often assign high confidence to different states at a given node. The two fully Bayesian methods disagree about the most probable reconstruction in about half of the nodes, even when similar likelihood models and similar priors are used. We suggest that similar studies should use several methods, awaiting an improved understanding of the statistical properties of the methods. A Lecanora-type ascus may have been ancestral in the Lecanorales. State transformations counts, obtained using stochastic mapping, indicate that the number of state changes is 12 to 24, which is considerably greater than the minimum three changes needed to explain the four observed ascus apex types. Apparently, the ascus in the Lecanorales is far more apt to change than has been recognized. Phylogeny corresponds well with morphology, although it partly contradicts currently used delimitations of the Crocyniaceae, Haematommataceae, Lecanoraceae, Megalariaceae, Mycoblastaceae, Pilocarpaceae, Psoraceae, Ramalinaceae, Scoliciosporaceae, and Squamarinaceae.


Subject(s)
Ascomycota/genetics , Biological Evolution , Lichens/genetics , Phylogeny
5.
Clin Sci (Lond) ; 110(6): 665-71, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16448385

ABSTRACT

Obesity is associated with metabolic syndrome and increased incidence of and mortality from myocardial infarction. The aim of the present study was to develop an animal model with metabolic syndrome and examine how that influences size of myocardial infarcts induced by occlusion and reperfusion of the left anterior descending coronary artery. Sprague-Dawley rats (n = 105) were fed either LF (low-fat) or MHF (moderately high-fat) diets for 13 weeks before coronary occlusion for 45 min, followed by reperfusion for 60 min. Compared with LF-fed and lean MHF-fed rats, obese MHF-fed rats developed metabolic disturbances similar to those seen in the metabolic syndrome, including being overweight by 24% (compared with lean MHF-fed rats), having 74% more visceral fat (compared with LF-fed rats), 15% higher blood pressure (compared with LF-fed rats), 116% higher plasma insulin (compared with lean MHF-fed rats), 10% higher fasting plasma glucose (compared with LF-fed rats), 35% higher non-fasting plasma glucose (compared with lean MHF-fed rats), 36% higher plasma leptin (compared with lean MHF-fed rats) and a tendency to lower plasma adiponectin and higher plasma non-esterified fatty acids. Infarct size was similar in the three groups of rats (36+/-14, 42+/-18 and 41+/-14% in obese MHF-fed, lean MHF-fed and LF-fed rats respectively). In conclusion, rats fed a MHF diet developed metabolic syndrome, but this did not influence myocardial infarct size.


Subject(s)
Metabolic Syndrome/pathology , Myocardial Infarction/pathology , Myocardial Reperfusion Injury/pathology , Myocardium/pathology , Adiponectin/blood , Animals , Blood Glucose/analysis , Cholesterol/blood , Fatty Acids, Nonesterified/blood , Insulin/blood , Leptin/blood , Male , Metabolic Syndrome/complications , Models, Animal , Myocardial Infarction/etiology , Myocardial Reperfusion Injury/complications , Rats , Rats, Sprague-Dawley
6.
Mycol Res ; 109(Pt 1): 21-30, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15736860

ABSTRACT

The phylogeny of the family Micareaceae and the genus Micarea was studied using mitochondrial small subunit ribosomal DNA sequences. Phylogenetic reconstructions were performed using Bayesian MCMC tree sampling and a maximum likelihood approach. The Micareaceae in its current sense is highly heterogeneous, and Helocarpon, Psilolechia, and Scutula, all thought to be close relatives of Micarea, are shown to be only distantly related. The genus Micarea is paraphyletic unless the entire Pilocarpaceae and Ectolechiaceae are included, as also indicated by an expected likelihood weights test. It is suggested that the Micareaceae is reduced to synonymy with the Pilocarpaceae, which also includes the Ectolechiaceae, and that Micarea may have to be divided into a series of smaller genera in the future. Micarea species with a 'non-micareoid' photobiont group with Psora and the Ramalinaceae, whereas Micarea intrusa appears to belong in Scoliciosporum. Three species fall inside the paraphyletic Micarea: Szczawinskia tsugae, Catillaria contristans, and Fellhaneropsis vezdae. Tropical foliicolous taxa are nested within groups of mainly temperate and arctic-alpine distribution. A 'micareoid' photobiont appears to be plesiomorphic in the Pilocarpaceae but has been lost a few times.


Subject(s)
Ascomycota/classification , Ascomycota/genetics , DNA, Mitochondrial/analysis , Lichens/microbiology , Phylogeny , Sequence Analysis, DNA , DNA, Fungal/analysis , DNA, Fungal/isolation & purification , DNA, Mitochondrial/genetics , DNA, Ribosomal/analysis , Evolution, Molecular
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