Late Carboniferous colonial Rugosa (Anthozoa) from Alaska

Late Carboniferous colonial corals from the Moscovian Saginaw Bay Formation and the underlying Bashkirian crinoidal limestone exposed on northeastern Kuiu Island and a nearby islet, part of the Alexander terrane in southeastern Alaska, are described and illustrated for the first time, and are supplemented by revision, redescription and reillustration of most Atokan specimens from Brooks Range, northern Alaska, first described by Armstrong (1972). New taxa from the Kuiu Island area include the new species Paraheritschioides katvalae and the new genus and species Arctistrotion variabilis, as well as the new Subfamily Arctistrotioninae. The corals Corwenia jagoensis and Lithostrotionella wahooensis of Armstrong (1972) also are redefined and redescribed. Paraheritschioides jagoensis is based on the holotype of ‘C’. jagoensis. P. compositus sp. nov. is based on a “paratype” of ‘C.’ jagoensis. In addition to a redefinition and redescription of ‘L.’ wahooensis as Arctistrotion wahooense, one “paratype” of that species is described as A. simplex sp. nov. The phylogeny and suspected relationships of some fasciculate Carboniferous Rugosa also are discussed. Based on relationships and similarities within the Late Carboniferous colonial Rugosa from the Brooks Range, Kuiu Island and the eastern Klamath terrane, we conclude that all three areas were geographically close enough at that time so that larvae were occasionally dispersed by oceanic currents. Distances between these areas, however, may have been so great and/or isolation so long that individual speciation occurred in all of the various locations. That hypothetical situation is reflected by a common generic, but not a specific, content of the particular faunas.ected by a common generic, but not a specific, content of the particular faunas

Late Carboniferous colonial Rugosa (Anthozoa) from Alaska

Late Carboniferous colonial corals from the Moscovian Saginaw Bay Formation and the underlying Bashkirian crinoidal limestone exposed on northeastern Kuiu Island and a nearby islet, part of the Alexander terrane in southeastern Alaska, are described and illustrated for the first time, and are supplemented by revision, re-description and re-illustration of most Atokan specimens from Brooks Range, northern Alaska, first described by Armstrong (1972). New taxa from the Kuiu Island area include the new species Paraheritschioides katvalae and the new genus and species Arctistrotion variabilis, as well as the new Subfamily Arctistrotioninae. The corals Corwenia jagoensis and Lithostrotionella wahooensis of Armstrong (1972) also are redefined and redescribed. Paraheritschioides jagoensis is based on the holotype of 'C'. jagoensis. P. compositus sp. nov. is based on a "paratype" of 'C.' jagoensis. In addition to a redefinition and redescription of 'L.' wahooensis as Arctistrotion wahooense, one "paratype" of that species is described as A. simplex sp. nov. The phylogeny and suspected relationships of some fasciculate Carboniferous Rugosa also are discussed. Based on relationships and similarities within the Late Carboniferous colonial Rugosa from the Brooks Range, Kuiu Island and the eastern Klamath terrane, we conclude that all three areas were geographically close enough at that time so that larvae were occasionally dispersed by oceanic currents. Distances between these areas, however, may have been so great and/or isolation so long that individual speciation occurred in all of the various locations. That hypothetical situation is reflected by a common generic, but not a specific, content of the particular faunas

New Late Carboniferous Heritschioidinae (Rugosa) from the Kuiu Island area and Brooks Range, Alaska

Three new species of the genus Heritschioides, i.e., H. alaskensis sp. nov., H. kuiuensis sp. nov., and H. splendidus sp. nov., and Kekuphyllum sandoense gen. et sp. nov. from the northeastern Kuiu Island area and nearby islets, part of Alexander terrane in southeastern Alaska, and Heritschioides separatus sp. nov. from the Brooks Range, Alaska, are described and illustrated. The three new fasciculate colonial coral species from the Kuiu Island area, collected from the Moscovian Saginaw Bay Formation, are phylogenetically related to those of probable Bashkirian age in the Brooks Range in northern Alaska as shown by the presence of morphologically similar species of Heritschioides. These corals from both areas also are related to one species in the Quesnel terrane in western Canada. Kekuphyllum sandoense from the Saginaw Bay Formation of the Kuiu Island area is the only cerioid-aphroid species within the Subfamily Heritschioidinae described so far. The complete early ontogeny of a protocorallite is for the first time described here on a basis of H. kuiuensis sp. nov. and compared to the hystero-ontogeny in order to show similarities and differences in those processes

When Blood Pressure Increases with Standing: Consensus Definition for Diagnosing Orthostatic Hypertension

When changing from the supine to the standing position approximately 500–1000 ml blood is pooled below the diaphragm and hydrostatic pressure forces fluids from the intravascular to the interstitial compartment. These changes impose a major hemodynamic burden on the cardiovascular system. Baroreflex-mediated withdrawal of cardiac parasympathetic activity and sympathetic activation maintain standing blood pressure in healthy persons. Orthostatic hypotension occurs when these counterregulatory mechanisms fail. Conversely, some patients have a paradoxical increase in upright blood pressure to hypertensive levels, presumably due to sympathetic activation overshoot. This orthostatic hypertension is not a benign condition because it is associated with increased cardiovascular morbidity and mortality independently of traditional risk factors.Citation1,Citation2 Yet, there has not been a uniform definition of orthostatic hypertension and the entity is not covered in current hypertension guidelines. Because diagnostic criteria vary profoundly between studies, data on epidemiology, associated health risks, and management of orthostatic hypertension in the existing literature is difficult to interpret

Do we need to evaluate diastolic blood pressure in patients with suspected orthostatic hypotension?

Purpose The contribution of diastolic blood pressure measurement to the diagnosis of classical orthostatic hypotension is not known. We aimed to explore the prevalence of isolated systolic and diastolic orthostatic hypotension components in patients with syncope and orthostatic intolerance. Methods: A total of 1520 patients aged >15 years with suspected syncope and/or symptoms of orthostatic intolerance were investigated in a tertiary center using tilt-table testing and continuous non-invasive blood pressure monitoring. Classical orthostatic hypotension was defined as a decline in systolic blood pressure ≥20 mmHg and/or diastolic blood pressure ≥10 mmHg at 3 min of tilt test. The prevalence of upright systolic blood pressure <90 mmHg and its overlap with isolated diastolic orthostatic hypotension was also assessed. Results: One hundred eighty-six patients (12.2%) met current diagnostic criteria for classical orthostatic hypotension. Of these, 176 patients (94.6%) met the systolic criterion and 102 patients (54.8%) met the diastolic criterion. Ninety-two patients (49.5%) met both systolic and diastolic criteria, whereas ten patients (5.4%) met the diastolic criterion alone. Of these, three had systolic blood pressure <90 mmHg during tilt test and were diagnosed with orthostatic hypotension on the grounds of low standing blood pressure. Based on patient history and ancillary test results, causes of orthostatic intolerance and syncope other than orthostatic hypotension were present in the remaining seven patients. Conclusions: An abnormal orthostatic fall in diastolic blood pressure without an abnormal fall in systolic blood pressure is rare among patients with syncope and orthostatic intolerance. Approximately 95% of patients with classical orthostatic hypotension can be identified by systolic criterion alone

Cyp2c70 is responsible for the species difference in bile acid metabolism between mice and humans

Bile acids are synthesized from cholesterol in the liver and subjected to multiple metabolic biotransformations in hepatocytes, including oxidation by cytochromes P450 (CYPs) and conjugation with taurine, glycine, glucuronic acid, and sulfate. Mice and rats can hydroxylate chenodeoxycholic acid (CDCA) at the 6β-position to form α-muricholic acid (MCA) and ursodeoxycholic acid (UDCA) to form β-MCA. However, MCA is not formed in humans to any appreciable degree and the mechanism for this species difference is not known. Comparison of several Cyp-null mouse lines revealed that α-MCA and β-MCA were not detected in the liver samples from Cyp2c-cluster null (Cyp2c-null) mice. Global bile acid analysis further revealed the absence of MCAs and their conjugated derivatives, and high concentrations of CDCA and UDCA in Cyp2c-null mouse cecum and feces. Analysis of recombinant CYPs revealed that α-MCA and β-MCA were produced by oxidation of CDCA and UDCA by Cyp2c70, respectively. CYP2C9-humanized mice have similar bile acid metabolites as the Cyp2c-null mice, indicating that human CYP2C9 does not oxidize CDCA and UDCA, thus explaining the species differences in production of MCA. Because humans do not produce MCA, they lack tauro-β-MCA, a farnesoid X receptor antagonist in mouse that modulates obesity, insulin resistance, and hepatosteatosis