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Reconstructing salinity conditions in Nares Strait (Canadian Archipelago) from stable isotope profiles in bivalve shells
Nares Strait is one of three main passages of the Canadian Archipelago that
channels freshwater from the Arctic Ocean to the North Atlantic. There are very few
observations regarding the role of this region on the present day Arctic freshwater budget,
and even less regarding the changes in freshwater fluxes through time. Larger scale
Arctic Ocean circulation features have recently been observed to shift. Such changes will
likely be manifest in Nares Strait before propagating into Baffin Bay and Labrador Sea.
The ÎŽ18O of the water in Nares Strait strongly co varies with salinity. We analyzed the
isotopic composition of bivalve shells collected live from the Greenland and Ellesmere
Island sides of the Strait in an effort to reconstruct salinity changes with time along this
passage over the 5-30 m depth range where these organisms live.
Specimens of Hiatella arctica and Astarte borealis collected at the northernmost
station show a strong shift towards lighter ÎŽ18O values in the most recently accreted
sections of their shells, which corresponds to significant freshening with salinity as low
as 23. These specimens at the northern end of Nares Strait began experiencing an
increase in freshwater input as far back as 20 years ago. Similar freshwater pulses occur
with diminishing frequency and magnitude through the 30 and 40 year timeslices. Lesser
signals occur further south, probably reflecting significant along channel mixing
Hydrographic Changes in Nares Strait (Canadian Arctic Archipelago) in Recent Decades Based on ÎŽ18O Profiles of Bivalve Shells
Nares Strait is one of three main passages of the Canadian Archipelago that channel relatively fresh seawater from the Arctic Ocean through Baffin Bay to the Labrador Sea. Oxygen isotopic profiles along the growth axis of bivalve shells, collected live over the 5 â 30 m depth range from the Greenland and Ellesmere Island sides of the strait, were used to reconstruct changes in the hydrography of the region over the past century. The variability in oxygen isotope ratios is mainly attributed to variations in salinity and suggests that the northern end of Nares Strait has been experiencing an increase in freshwater runoff since the mid 1980s. The recent changes are most pronounced at the northern end of the strait and diminish toward the south, a pattern consistent with proximity to the apparently freshening Arctic Ocean source in the north and mixing with Baffin Bay waters as the water progresses southward. This increasing freshwater signal may reflect changes in circulation and ice formation that favor an increased flow of relatively fresh waters from the Arctic Ocean into Nares Strait.Le dĂ©troit de Nares est lâun des trois principaux passages de lâarchipel canadien qui canalise de lâeau de mer relativement fraĂźche de lâocĂ©an Arctique jusquâĂ la mer du Labrador en passant par la baie de Baffin. Les profils de la composition isotopique de lâoxygĂšne le long de lâaxe de dĂ©veloppement des coquillages bivalves recueillis en vie Ă une profondeur variant entre 5 Ă 30 m des cĂŽtĂ©s du dĂ©troit Ă la hauteur du Groenland et de lâĂźle dâEllesmere ont servi Ă reconstruire les changements ayant caractĂ©risĂ© lâhydrographie de la rĂ©gion au cours du dernier siĂšcle. La variabilitĂ© en matiĂšre de ratio dâisotope de lâoxygĂšne est principalement attribuable aux variations de salinitĂ©, ce qui laisse entendre que lâextrĂ©mitĂ© nord du dĂ©troit de Nares connaĂźt une augmentation de lâĂ©coulement dâeau douce depuis le milieu des annĂ©es 1980. Les changements rĂ©cents sont plus prononcĂ©s Ă lâextrĂ©mitĂ© nord du dĂ©troit et diminuent en arrivant vers le sud, ce qui constitue une tendance conforme Ă la proximitĂ© de la source de lâocĂ©an Arctique en dessalure apparente dans le nord et qui se mĂ©lange avec les eaux de la baie de Baffin au fur et Ă mesure que lâeau progresse vers le sud. Cette augmentation de la prĂ©sence dâeau douce peut ĂȘtre le reflet de changements en matiĂšre de circulation et de formation de la glace qui favorisent un Ă©coulement accru dâeaux relativement douces en provenance de lâocĂ©an Arctique et se jettent dans le dĂ©troit de Nares
Comparison of the Safety and Pharmacokinetics of ST-246Âź after IV Infusion or Oral Administration in Mice, Rabbits and Monkeys
ST-246Âź is an antiviral, orally bioavailable small molecule in clinical development for treatment of orthopoxvirus infections. An intravenous (IV) formulation may be required for some hospitalized patients who are unable to take oral medication. An IV formulation has been evaluated in three species previously used in evaluation of both efficacy and toxicology of the oral formulation. plasma concentrations. These effects were eliminated using slower IV infusions. associated toxicity. Shorter infusions at higher doses in NHP resulted in decreased clearance, suggesting saturated distribution or elimination. Elimination half-lives in all species were similar between oral and IV administration. The administration of ST-246 was well tolerated as a slow IV infusion
Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009aâb; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported
by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on
18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based
researchers who signed it in the short time span from 20 September to 6 October 2016
Hydrographic changes in Nares Strait (Canadian Arctic Archipelago) in recent decades based on delta 18O profiles of bivalve shells
Nares Strait is one of three main passages of the Canadian Archipelago that channel relatively fresh seawater from the Arctic Ocean through Baffin Bay to the Labrador Sea. Oxygen isotopic profiles along the growth axis of bivalve shells, collected live over the 5-30 m depth range from the Greenland and Ellesmere Island sides of the strait, were used to reconstruct changes in the hydrography of the region over the past century. The variability in oxygen isotope ratios is mainly attributed to variations in salinity and suggests that the northern end of Nares Strait has been experiencing an increase in freshwater runoff since the mid 1980s. The recent changes are most pronounced at the northern end of the strait and diminish toward the south, a pattern consistent with proximity to the apparently freshening Arctic Ocean source in the north and mixing with Baffin Bay waters as the water progresses southward. This increasing freshwater signal may reflect changes in circulation and ice formation that favor an increased flow of relatively fresh waters from the Arctic Ocean into Nares Strait
Variants supporting other genetic diagnoses.
Background and aimGene defects contribute to the aetiology of intrahepatic cholestasis. We aimed to explore the outcome of whole-exome sequencing (WES) in a cohort of 51 patients with this diagnosis.Patients and methodsBoth paediatric (n = 33) and adult (n = 18) patients with cholestatic liver disease of unknown aetiology were eligible. WES was used for reassessment of 34 patients (23 children) without diagnostic genotypes in ABCB11, ATP8B1, ABCB4 or JAG1 demonstrable by previous Sanger sequencing, and for primary assessment of additional 17 patients (10 children). Nasopharyngeal swab mRNA was analysed to address variant pathogenicity in two families.ResultsWES revealed biallelic variation in 3 ciliopathy genes (PKHD1, TMEM67 and IFT172) in 4 clinically unrelated index subjects (3 children and 1 adult), heterozygosity for a known variant in PPOX in one adult index subject, and homozygosity for an unreported splice-site variation in F11R in one child. Whereas phenotypes of the index patients with mutated PKHD1, TMEM67, and PPOX corresponded with those elsewhere reported, how F11R variation underlies liver disease remains unclear. Two unrelated patients harboured different novel biallelic variants in IFT172, a gene implicated in short-rib thoracic dysplasia 10 and Bardet-Biedl syndrome 20. One patient, a homozygote for IFT172 rs780205001 c.167A>C p.(Lys56Thr) born to first cousins, had liver disease, interpreted on biopsy aged 4y as glycogen storage disease, followed by adult-onset nephronophthisis at 25y. The other, a compound heterozygote for novel frameshift variant IFT172 NM_015662.3 c.2070del p.(Met690Ilefs*11) and 2 syntenic missense variants IFT172 rs776310391 c.157T>A p.(Phe53Ile) and rs746462745 c.164C>G p.(Thr55Ser), had a severe 8mo cholestatic episode in early infancy, with persisting hyperbilirubinemia and fibrosis on imaging studies at 17y. No patient had skeletal malformations.ConclusionOur findings suggest association of IFT172 variants with non-syndromic cholestatic liver disease.</div
Demographic characteristics and phenotypes of enrolled index subjects.
Demographic characteristics and phenotypes of enrolled index subjects.</p
List of referring centres.
Background and aimGene defects contribute to the aetiology of intrahepatic cholestasis. We aimed to explore the outcome of whole-exome sequencing (WES) in a cohort of 51 patients with this diagnosis.Patients and methodsBoth paediatric (n = 33) and adult (n = 18) patients with cholestatic liver disease of unknown aetiology were eligible. WES was used for reassessment of 34 patients (23 children) without diagnostic genotypes in ABCB11, ATP8B1, ABCB4 or JAG1 demonstrable by previous Sanger sequencing, and for primary assessment of additional 17 patients (10 children). Nasopharyngeal swab mRNA was analysed to address variant pathogenicity in two families.ResultsWES revealed biallelic variation in 3 ciliopathy genes (PKHD1, TMEM67 and IFT172) in 4 clinically unrelated index subjects (3 children and 1 adult), heterozygosity for a known variant in PPOX in one adult index subject, and homozygosity for an unreported splice-site variation in F11R in one child. Whereas phenotypes of the index patients with mutated PKHD1, TMEM67, and PPOX corresponded with those elsewhere reported, how F11R variation underlies liver disease remains unclear. Two unrelated patients harboured different novel biallelic variants in IFT172, a gene implicated in short-rib thoracic dysplasia 10 and Bardet-Biedl syndrome 20. One patient, a homozygote for IFT172 rs780205001 c.167A>C p.(Lys56Thr) born to first cousins, had liver disease, interpreted on biopsy aged 4y as glycogen storage disease, followed by adult-onset nephronophthisis at 25y. The other, a compound heterozygote for novel frameshift variant IFT172 NM_015662.3 c.2070del p.(Met690Ilefs*11) and 2 syntenic missense variants IFT172 rs776310391 c.157T>A p.(Phe53Ile) and rs746462745 c.164C>G p.(Thr55Ser), had a severe 8mo cholestatic episode in early infancy, with persisting hyperbilirubinemia and fibrosis on imaging studies at 17y. No patient had skeletal malformations.ConclusionOur findings suggest association of IFT172 variants with non-syndromic cholestatic liver disease.</div