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Evidence for Two Pulses of Glaciation during the Late Proterozoic in Northern Utah and Southeastern Idaho
A record of glaciation during late Proterozoic time is preserved in a number of localities extending from the Sheeprock Mountains, Utah, to Pocatello, Idaho, and from the Park City area 40 km east of Salt Lake City to the Deep Creek Range along the Utah-Nevada line. Over much of this area, the glacial deposits and associated rocks thicken westward and form the basal part of a miogeoclinal wedge that accumulated near the late Proterozoic and early Paleozoic continental margin. In the east, such deposits are thin and rest on Archean basement or rocks of Proterozoic Y age; in the west, they are part of thicker sequences in which deposition apparently continued without significant interruption from late Proterozoic into Cambrian time. In many places, the original continuity between the western and eastern parts of the depositional wedge has been obscured by thrusting of Cretaceous and early Tertiary age that carried the thick basinal sequences eastward over those deposited on the continental platform. Recent mapping of Fremont Island in Great Salt Lake, the Wasatch Range between Ogden and Brigham City, and the Sheeprock Mountains shows that glacial episodes represented either by diamictite or by dropstones enclosed in finegrained laminated beds are separated by as much as 1,000 m of non-glacial deposits, including black slate, alternating graywacke and siltstone, quartzite, and conglomerate. Using reasonable sedimentation rates for such deposits and by comparison with modern analogues, we infer that two episodes of glaciation, each probably consisting of multiple advances and retreats, were separated by a non-glacial interval of a few hundred thousand to a few million years' duration. Correlation of the allochthonous, miogeoclinal glacial deposits with the single glacial unit present in autochthonous and parautochthonous platform sites is uncertain, but our interpretation of sedimentary facies and paleogeography suggests that only the younger of the two episodes recorded in the allochthon is represented by the diamictites of the autochthon
Дуоденум-сохраняющая резекция головки поджелудочной железы при хроническом панкреатите, доброкачественных и предраковых опухолях поджелудочной железы
ПОДЖЕЛУДОЧНАЯ ЖЕЛЕЗА /ПАТОЛОГ /ХИРНОВООБРАЗОВАНИЯ КИСТОЗНЫЕ, СЛИЗИСТЫЕ И СЕРОЗНЫЕНЕЙРОЭНДОКРИННЫЕ НОВООБРАЗОВАНИЯНЕЙРОЭНДОКРИННЫЕ ОПУХОЛИПАНКРЕАТИТХРОНИЧЕСКИЙ ПАНКРЕАТИТПАНКРЕАТОДУОДЕНЭКТОМИЯДУОДЕНОПАНКРЕАТЭКТОМИЯПАНКРИАТИКОДУОДЕНЭКТОМИЯОПЕРАЦИЯ УИПЛАДУОДЕНУМ-СОХРАНЯЮЩАЯ РЕЗЕКЦИЯ ГОЛОВКИ ПОДЖЕЛУДОЧНОЙ ЖЕЛЕЗЫПОСЛЕОПЕРАЦИОННЫЕ ОСЛОЖНЕНИЯЦель. Сообщить об опыте применения в клинике дуоденум-сохраняющей резекции головки поджелудочной железы (ДСРГПЖ) как метода хирургического лечения хронического панкреатита с воспалительным инфильтратом, доброкачественных и предраковых новообразований, а также нейроэндокринных опухолей головки поджелудочной железы. Материал и методы. ДСРГПЖ является операцией, при которой сохраняется антральный отдел желудка, общий желчный проток и двенадцатиперстная кишка, в то время как операция Уиппла относится к мультивисцеральной операции, включающей в себя дуоденэктомию. Дуоденум-сохраняющая резекция головки поджелудочной железы была впервые применена в нашей клинике в Берлине в 1969 году. Результаты. При хроническом панкреатите (ХП) с воспалительным инфильтратом в головке ПЖ ДСРГПЖ стала стандартным хирургическим вмешательством, принятым во всем мире. В группе из 603 пациентов с ХП, перенесших ДСРГПЖ, частота панкреатических свищей была 3,3%, внутрибрюшных абсцессов – 2,8%, кровотечения – 2,8%, повторных операций – 5,6%, летальности – 0,82% и повторной госпитализации в течение 90 дней – 8%. ДСРГПЖ при доброкачественных и предраковых кистозных новообразованиях головки ПЖ в основном используется для IPNM (инвазивный внутрипротоковый папиллярный рак), MCN (муцинозная киста) и SPN (серозная киста). В обзоре иностранных публикаций, включающих 503 пациентов, частота общих осложнений была 38,2%, тяжелых послеоперационных осложнений – 12,7%. из них панкреатические свищи В+С (по классификации ISGPF) наблюдались у 13,6%, повторные операции – у 2,7% и летальность в течение 90 дней – у 0,4%. При использовании ДСРГПЖ при нейроэндокринных опухолях головки ПЖ рекомендуется дополнительная локальная лимфодиссекция. Отдаленные осложнения ДСРГПЖ, такие как сахарный диабет и экзокринная дисфункция, наблюдаются только у 5-7% пациентов. Заключение. Операция Уиппла сопровождается значительным количеством метаболических осложнений. ДСРГПЖ при воспалительных опухолях, доброкачественных и предраковых новообразованиях, нейроэндокринных опухолях головки поджелудочной железы имеет преимущества в сохранении двенадцатиперстной кишки и поддержании эндокринной и экзокринной функции ПЖ.Objective. To report the institutional experience of the evolution of duodenum-preserving pancreatic head resection (DPPHR) as a surgical treatment for chronic pancreatitis with an inflammatory tumor as well as cystic and benign, premalignant neoplasms and neuroendocrine tumors of the pancreatic head. Methods. DPPHR is associated with preservation of gastric antrum, common bile duct and duodenum/upper jejunal loop, contrary to Kausch-Whipple resection, which is a multivisceral procedure, including duodenectomy. Duodenum-preserving pancreatic head resection was first established in clinical setting in Berlin in 1969. Results. For chronic pancreatitis with an inflammatory infiltrat in the pancreatic head, duodenum-preserving pancreatic head resection has become a standard surgical treatment with worldwide acceptance. In a series of 603 patients with chronic pancreatitis following DPPHR, the frequency of pancreatic fistula was 3.3 %, intra-abdominal abscess 2.8 %, hemorrhage 2.8 %, frequency of reoperation 5.6%, in-hospital mortality 0.82 % and 90-day rehospitalisation 8 %. DPPHR for benign and premalignant cystic neoplasms of the pancreatic head is used predominantly for IPMN, MCN and SPN tumors. In a review of international publications comprising 503 patients, the general morbidity was 38.2 %, severe surgery-related complications 12.7% of them pancreatic fistula B+C 13.6 %, resurgery 2.7 % and 90-day mortality 0.4 %. When pancreatic neuroendocrine tumors of pancreatic head are treated with DPPHR, a local lymph node dissection is additionally recommended. The long-term morbidity following DPPHR revealed new onset of diabetes mellitus and exocrine dysfunctions in only 5-7 % of patients. Conclusion. Kausch-Whipple resection is associated with considerable high metabolic complications. Duodenum-sparing pancreatic head resection for inflammatory tumor, benign and premalignant neoplasms, and neuroendocrine tumors of the pancreatic head has the advantage of the duodenum preservation and maintenance of the pancreatic endocrine and exocrine functions
Effects of seawater and freshwater challenges on the Gh/Igf system in the saline-tolerant blackchin tilapia (Sarotherodon melanotheron)
Prolactin (Prl) and growth hormone (Gh) as well as insulin-like growth factor 1 (Igf1) are involved in the physiological adaptation of fish to varying salinities. The Igfs have been also ascribed other physiological roles during development, growth, reproduction and immune regulation. However, the main emphasis in the investigation of osmoregulatory responses has been the endocrine, liver-derived Igf1 route and local regulation within the liver and osmoregulatory organs. Few studies have focused on the impact of salinity alterations on the Gh/Igf-system within the neuroendocrine and immune systems and particularly in a salinity-tolerant species, such as the blackchin tilapia Sarotherodon melanotheron. This species is tolerant to hypersalinity and saline variations, but it is confronted by severe climate changes in the Saloum inverse estuary. Here we investigated bidirectional effects of increased salinity followed by its decrease on the gene regulation of prl, gh, igf1, igf2, Gh receptor and the tumor-necrosis factor a. A mixed population of sexually mature 14-month old blackchin tilapia adapted to freshwater were first exposed to seawater for one week and then to fresh water for another week. Brain, pituitary, head kidney and spleen were excised at 4 h, 1, 2, 3 and 7 days after both exposures and revealed differential expression patterns. This investigation should give us a better understanding of the role of the Gh/Igf system within the neuroendocrine and immune organs and the impact of bidirectional saline challenges on fish osmoregulation in non-osmoregulatory organs, notably the complex orchestration of growth factors and cytokines
Enhancing scientific communication skills: a real-world simulation in a tertiary-level life science class using e-learning technology in biomedical literature perception, reflective review writing on a clinical issue, and self and peer assessments
This educational study aimed to explore the feasibility and acceptance of a literacy exercise adopted from the realworld of scientific publishing in a cell and tissue biology course. For that purpose, a tertiary-level multimodality science course, which integrated a blended learning faculty and student lectures, journal club, and wet laboratory sessions including a research project as well as examinations, was complemented by essaywriting of a review and peerreviewing of five manuscripts. All tasks contributed to the final course mark. Special emphasis was laid on the usability of different E-Learning applications for scientific writing and teacher- and peerassessment procedures. Further, potential influences of student characteristics on their peerand self-assessments as well as their acceptance of the feedback from their peers were evaluated. Seventy-five undergraduate students from different Bachelor programs were included in the study. Plagiarism check and double-blind assessments of the essays were performed using “Turnitin.com.” Students self- assessed their paper and received feedback from five peers and the teacher. Peer assessment was more severe than the teacher- or self-assessment, and the peer mark correlated best with the final course mark. Students with better marks assessed more generously, and there had moderate tendencies for influences of gender and background on peer feedback behavior. The students perceived the writing and assessment exercises, especially being peer-assessed, as demanding, but rewarding and a great learning experience. The additional tasks were feasible using E-Learning technology, which should foster future biomedical courses to train writing skills and the ability to cope with different roles in the scientific community
Increase in CGRP- and nNOS-immunoreactive neurons in the rat trigeminal ganglion after infusion of an NO donor
Background: Nitrovasodilators, such as glyceroltrinitrate (GTN), which produce nitric oxide (NO) in the organism, are known to cause delayed headaches in migraineurs, accompanied by increased plasma levels of calcitonin gene-related peptide (CGRP) in the cranial venous outflow. Increases in plasma CGRP and NO metabolites have also been found in spontaneous migraine attacks. In a rat model of meningeal nociception, infusion of NO donors induced activity of neurons in the spinal trigeminal nucleus.
Methods: Isoflurane-anaesthetised rats were intravenously infused with GTN (250 µg/kg) or saline for two hours and fixed by perfusion after a further four hours. Cryosections of dissected trigeminal ganglia were immunostained for detection of CGRP and neuronal NO synthase (nNOS). The ganglion neurons showing immunofluorescence for either of these proteins were counted.
Results: The proportions of CGRP- and nNOS- as well as double-immunopositive neurons were increased after GTN infusion compared to saline treatment in all parts of the trigeminal ganglion (CGRP) or restricted to the ophthalmic region (nNOS). The size of immunopositive neurons was not significantly different compared to controls.
Conclusion: High levels of NO may induce the expression or availability of CGRP and nNOS. Similar changes may be involved in nitrovasodilator-induced and spontaneous headache attacks in migraineurs
Stable long-term risk of leukaemia in patients with severe congenital neutropenia maintained on G-CSF therapy
In severe congenital neutropenia (SCN), long-term therapy with granulocyte colony-stimulating factor (G-CSF) has reduced mortality from sepsis, revealing an underlying predisposition to myelodysplastic syndrome and acute myeloid leukaemia (MDS/AML). We have reported the early pattern of evolution to MDS/AML, but the long-term risk remains uncertain. We updated a prospective study of 374 SCN patients on long-term G-CSF enrolled in the Severe Chronic Neutropenia International Registry. Long-term, the annual risk of MDS/AML attained a plateau (2·3%/year after 10 years). This risk now appears similar to, rather than higher than, the risk of AML in Fanconi anaemia and dyskeratosis congenita.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79264/1/j.1365-2141.2010.08216.x.pd
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