Bio-optical evidence for increasing Phaeocystis dominance in the Barents Sea.

Increasing contributions of prymnesiophytes such as Phaeocystis pouchetii and Emiliania huxleyi to Barents Sea (BS) phytoplankton production have been suggested based on in situ observations of phytoplankton community composition, but the scattered and discontinuous nature of these records confounds simple inference of community change or its relationship to salient environmental variables. However, provided that meaningful assessments of phytoplankton community composition can be inferred based on their optical characteristics, ocean-colour records offer a potential means to develop a synthesis between sporadic in situ observations. Existing remote-sensing algorithms to retrieve phytoplankton functional types based on chlorophyll-a (chl-a) concentration or indices of pigment packaging may, however, fail to distinguish Phaeocystis from other blooms of phytoplankton with high pigment packaging, such as diatoms. We develop a novel algorithm to distinguish major phytoplankton functional types in the BS and apply it to the MODIS-Aqua ocean-colour record, to study changes in the composition of BS phytoplankton blooms in July, between 2002 and 2018, creating time series of the spatial distribution and intensity of coccolithophore, diatom and Phaeocystis blooms. We confirm a north-eastward expansion in coccolithophore bloom distribution, identified in previous studies, and suggest an inferred increase in chl-a concentrations, reported by previous researchers, may be partly explained by increasing frequencies of Phaeocystis blooms. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.

Laparoscopic common bile duct exploration; a preferential pathway for elderly patients.

BACKGROUND: Laparoscopic common bile duct exploration (LCBDE) has emerged as a recommended alternative to endoscopic retrograde cholangiopancreatography (ERCP) for the management of choledocholithiasis. However, its use in the elderly has been limited, and evidence of its safety and efficacy in these patients is yet to be established. This study describes our experience of LCBDE in elderly patients, analysing the safety and efficacy of this technique in comparison to younger patients. METHODS: All patients undergoing laparoscopic cholecystectomy (LC) with LCBDE for choledocholithiasis in our unit between January 2015 and January 2017 were included. Data pertaining to patient demographics, comorbidities, investigations, operative technique and outcomes were analysed. Patients were divided into 2 groups based on age (Group A:<65 years vs Group B: >/ = 65 years) for comparative analysis. RESULTS: 124 patients (Group A: 65, Group B: 59) were included. Group B were more co-morbid and had a higher ASA grade than Group A. However, there was no significant difference between groups in rates of conversion to open or complications, including bile leak (3.1% vs 5.1%, p = 0.67), retained stone (4.6% vs 1.7%, p = 0.62), or complications according to Clavien-Dindo classification (p = 0.78). Re-intervention rates were also similar between groups (7.7% vs 3.4%, p = 0.44 and 3.1% vs 3.4%, p = 1.0 respectively), as was length of stay. CONCLUSION: Despite higher frequency of comorbidities and ASA grade, LCBDE in elderly patients is safe and effective, and has similar outcomes to younger patients. Therefore elderly patients with choledocholithiasis should be offered LCBDE as an alternative to ERCP.

Phenological Responses to ENSO in the Global Oceans.

Phenology relates to the study of timing of periodic events in the life cycle of plants or animals as influenced by environmental conditions and climatic forcing. Phenological metrics provide information essential to quantify variations in the life cycle of these organisms. The metrics also allow us to estimate the speed at which living organisms respond to environmental changes. At the surface of the oceans, microscopic plant cells, so-called phytoplankton, grow and sometimes form blooms, with concentrations reaching up to 100 million cells per litre and extending over many square kilometres. These blooms can have a huge collective impact on ocean colour, because they contain chlorophyll and other auxiliary pigments, making them visible from space. Phytoplankton populations have a high turnover rate and can respond within hours to days to environmental perturbations. This makes them ideal indicators to study the first-level biological response to environmental changes. In the Earth's climate system, the El Niño-Southern Oscillation (ENSO) dominates large-scale inter-annual variations in environmental conditions. It serves as a natural experiment to study and understand how phytoplankton in the ocean (and hence the organisms at higher trophic levels) respond to climate variability. Here, the ENSO influence on phytoplankton is estimated through variations in chlorophyll concentration, primary production and timings of initiation, peak, termination and duration of the growing period. The phenological variabilities are used to characterise phytoplankton responses to changes in some physical variables: sea surface temperature, sea surface height and wind. It is reported that in oceanic regions experiencing high annual variations in the solar cycle, such as in high latitudes, the influence of ENSO may be readily measured using annual mean anomalies of physical variables. In contrast, in oceanic regions where ENSO modulates a climate system characterised by a seasonal reversal of the wind forcing, such as the monsoon system in the Indian Ocean, phenology-based mean anomalies of physical variables help refine evaluation of the mechanisms driving the biological responses and provide a more comprehensive understanding of the integrated processes.

Obesity, diabetes, and leptin resistance promote tau pathology in a mouse model of disease.

Obesity and type 2 diabetes mellitus (T2DM) convey an increased risk for developing dementia. The microtubule-associated protein tau is implicated in neurodegenerative disease by undergoing hyperphosphorylation and aggregation, leading to cytotoxicity and neurodegeneration. Enzymes involved in the regulation of tau phosphorylation, such as GSK3ß, are tightly associated with pathways found to be dysregulated in T2DM. We have shown previously that leptin-resistant mice, which develop obesity and a diabetic phenotype, display elevated levels of tau phosphorylation. Here we show cells cultured with leptin, an adipokine shown to have neuroprotective effects, reduces tau phosphorylation. To explore how this mechanism works in vivo we transduced an existing diabetic mouse line (Lepr(db/db)) with a tau mutant (tau(P301L)) via adeno-associated virus (AAV). The resulting phenotype included a striking increase in tau phosphorylation and the number of neurofibrillary tangles (NFTs) found within the hippocampus. We conclude that leptin resistance-induced obesity and diabetes accelerates the development of tau pathology. This model of metabolic dysfunction and tauopathy provides a new system in which to explore the mechanisms underlying the ways in which leptin resistance and diabetes influence development of tau pathology, and may ultimately be related to the development of NFTs.

'Born in Michigan? You're in the biobank': engaging population biobank participants through Facebook advertisements.

BACKGROUND/AIMS: Despite a broad call for biobanks to use social media, data is lacking regarding the capacity of social media tools, especially advertising, to engage large populations on this topic. METHODS: We used Facebook advertising to engage Michigan residents about the BioTrust for Health. We conducted a low-budget (

Invasive species threat: parasite phylogenetics reveals patterns and processes of host-switching between non-native and native captive freshwater turtles.

One of the major threats to biodiversity involves biological invasions with direct consequences on the stability of ecosystems. In this context, the role of parasites is not negligible as it may enhance the success of invaders. The red-eared slider, Trachemys scripta elegans, has been globally considered among the worst invasive species. Since its introduction through the pet trade, T. s. elegans is now widespread and represents a threat for indigenous species. Because T. s. elegans coexists with Emys orbicularis and Mauremys leprosa in Europe, it has been suggested it may compete with the native turtle species and transmit pathogens. We examined parasite transfer from American captive to the two native species that co-exist in artificial pools of a Turtle Farm in France. As model parasite species we used platyhelminth worms of the family Polystomatidae (Monogenea) because polystomes have been described from American turtles in their native range. Phylogenetic relationships among polystomes parasitizing chelonian host species that are geographically widespread show patterns of diversification more complex than expected. Using DNA barcoding to identify species from adult and/or polystome eggs, several cases of host switching from exotic to indigenous individuals were illustrated, corroborating that parasite transmission is important when considering the pet trade and in reintroduction programmes to reinforce wild populations of indigenous species.

Normal inflammatory markers in appendicitis: evidence from two independent cohort studies.

OBJECTIVES: Acute appendicitis is a common surgical condition which can lead to severe complications. Recent work suggested that patients experiencing right lower abdominal pain, with normal white cell count (WCC) and C-reactive protein (CRP) are unlikely to have acute appendicitis and can be discharged. We present two independent data-sets that suggest that this strategy may not be risk-free. DESIGN: Retrospective cohort study of consecutive patients from two district general hospitals. Sensitivity and specificity of CRP, WCC and neutrophil count (NC) in predicting appendicitis were calculated. Markers were analysed using Fisher's exact test and Kruskul-Wallace test. SETTING: Two district general hospitals in the UK. PARTICIPANTS: Patients undergoing appendicectomy for suspected appendicitis. MAIN OUTCOME MEASURES: Inflammatory markers and appendix histology. RESULTS: A total of 297 patients were included. Appendicitis occurred in four patients with normal CRP, WCC and NC in centre A and 13 patients in centre B. The sensitivity of all three markers combined was 94% (centre A) and 92% (centre B). The specificity was 60% (centre A) and 64% (centre B). No single marker could differentiate uncomplicated and complicated appendicitis, but a raised NC or a CRP >35.5 mg/l predicted complicated appendicitis. CRP, WCC and NC combined differentiated between patients with a normal appendix, uncomplicated appendicitis and complicated appendicitis. CONCLUSIONS: Appendicitis in the presence of normal inflammatory markers is not uncommon. We disagree with the view of Sengupta et al. who suggest that patients with normal WCC and CRP are unlikely to have appendicitis, and recommend that clinicians be wary of normal inflammatory markers in patients with a high clinical suspicion of appendicitis.

A lifetime of fear of being laughed at: an aged perspective.

This paper reviews recent literature on gelotophobia (i.e., the fear of being laughed at) with an emphasis on age-specific aspects. Research with two instruments, the GELOPH and PhoPhiKat questionnaires, is presented with special attention being given to sociodemographic correlates and differences in intelligence, character strengths, personality, emotion, and humor. Quite consistently gelotophobes tend to misread positively motivated smiling and laughter (e.g. in social interactions, photographs or auditorily presented) and have lower values in many, but not all, components of humor. They have a low propensity to joy and a disposition to experience shame and fear. More generally they tend to describe themselves as being introverted and neurotic, and they underestimate their own potential while not actually being less capable. Furthermore, new data are presented suggesting that age-related vulnerabilities may be additional sources of ridicule making gelotophobia more of a problem for the elderly. Finally, the prevalence of this fear over the lifespan and potential cohort effects are discussed. It is concluded that more research into this fear and its adverse impact on social interactions, even humorous ones, of the elderly is needed.

Basin-scale coherence in phenology of shrimps and phytoplankton in the North Atlantic Ocean.

Climate change could lead to mismatches between the reproductive cycles of marine organisms and their planktonic food. We tested this hypothesis by comparing shrimp (Pandalus borealis) egg hatching times and satellite-derived phytoplankton bloom dynamics throughout the North Atlantic. At large spatial and long temporal (10 years or longer) scales, hatching was correlated with the timing of the spring phytoplankton bloom. Annual egg development and hatching times were determined locally by bottom water temperature. We conclude that different populations of P. borealis have adapted to local temperatures and bloom timing, matching egg hatching to food availability under average conditions. This strategy is vulnerable to interannual oceanographic variability and long-term climatic changes.

Rhinoclemmysnema n. g. and three new species of nematodes of the family Atractidae (Cosmocercoidea), with notes on the helminth fauna of Rhinoclemmys pulcherrima (Testudines: Bataguridae) in Costa Rica.

Rhinoclemmysnema n. g. and three new species of atractid nematodes, namely, Atractis costaricaensis n. sp., Orientatractis asymmetrica n. sp. and Rhinoclemmysnema multilabiatum were recovered from the small and large intestine of Rhinoclemmys pulcherrima, the painted wood turtle in the Guanacaste Conservation Area, Costa Rica. The genera and three species are characterized by the features of the cephalic region and male tail. Neopolystoma fentoni (conjuctival sac) and Heronimus mollis (lungs) were also collected.

Description of Buckarootrema goodmani n. g., n. sp. (Digenea: Pronocephalidae), a parasite of the freshwater turtle Emydura macquarii (Gray, 1830) (Pleurodira: Chelidae) from Queensland, Australia, and a phylogenetic analysis of the genera of the Pronocephalidae Looss, 1902.

Buckarootrema goodmani n. g., n. sp. is described from the small intestine of the Murray turtle, Emydura macquarii (Gray, 1830), from the vicinity of Warwick, Queensland, Australia. The distinctive taxonomic features include the vitellarium, which consists of 2 compact masses directly anterior to and occasionally overlapping the testes; the uterus with extensive pre- and postovarian coils; intestinal ceca with small, medial diverticula that terminate anterior to or at the anterior margin of the testes; a comma-shaped cirrus sac with both internal and external seminal vesicles. Phylogenetic systematic analysis of the genera of the Pronocephalidae including Buckarootrema and Notopronocephalus, the only other genus of pronocephalids reported from Australian freshwater turtles, indicates that Buckarootrema is the sister taxon of Neopronocephalus and Notopronocephalus is the sister group of the rest of the Pronocephalinae.

Neopolystoma fentoni n. sp. (Monogenea: Polystomatidae) a parasite of the conjunctival sac of freshwater turtles in Costa Rica.

Neopolystoma fentoni n. sp. is described from the conjunctival sac of Kinosternon leucostomum (Duméril, Bibron, and Duméril 1851) and Rhinoclemmys pulcherrima (Gray 1855) from the Guanacaste Conservation Area in Costa Rica. The new species differs from all other species of Neopolystoma, except N. elizabethae Platt 2000 in possessing a circle of eight genital spines that are recurved and possess a crescent-shaped base. N. fentoni n. sp. differs from N. elizabethae in lacking cecal diverticula and in a number of morphometric criteria.

Helminth parasites of the western painted turtle, Chrysemys picta belli (Gray), including Neopolystoma elizabethae n. sp. (Monogenea: Polystomatidae), a parasite of the conjunctival sac.

Neopolystoma elizabethae n. sp. is described from the conjunctival sac of the western painted turtle Chrysemys picta belli (Gray), from the Upper Peninsula of Michigan. This is the first species found in this location from chelonians in North America. The new species differs from all other species of Neopolystoma in possessing a circle of 8 genital spines that are recurved and possess a crescent-shaped base. Eight additional species of helminths were found in the 5 turtles examined in this study. All are common parasites of North American freshwater turtles. An additional species of Monogenea (Polystomoidespauli) was found in the oral cavity. Four species of Digenea (Eustomos chelydrae, Allassostomoides chelydrae, Spirorchis kirki, and Spirorchis parvus) and 3 species of Nematoda (Spiroxys contorta, Serpinema trispinosus, and Amphibiocapillaria serpentina) were also found. The following are reported from Michigan for the first time: P. pauli, S. kirki, and A. serpentina.

Description and life-cycle of three new species of Dingularis n.g. (Digena: Plagiorchiida), parasites of Australian freshwater turtles.

Dingularus n.g. is proposed to accommodate three new species, D. anfracticirrus, D. pearsoni and D. megapharynx, within the Plagiorchiida. Dingularus is closely related to the Plagiorchiidae, despite the unusual excretory systems of the three species. Adult worms were parasitic in the intestines of freshwater turtles, Chelodina expansa (D. pearsoni and D. megapharynx) and Emydura macquarii (D. anfracticirrus), and appeared to be host-specific. The three species had similar, three-host, aquatic life-cycles and each life-cycle was followed experimentally. The planorbid snail Glyptophysa gibbosa served as the first intermediate host for each species. Tadpoles of Limnodynastes peronii and snails G. gibbosa and Austropeplea lessoni served as second intermediate hosts. Dingularus spp. eggs were fully embryonated and infective when laid. They remained viable for 2-3 months in water but did not hatch until eaten by G. gibbosa. Miracidia were stimulated in the stomach of the snail host but did not hatch until eggs passed into the intestine. Hatching occurred in only the anterior fifth of the intestine. Hatched miracidia were not passed with the snail faeces. The pre-patent period in the snail differed in each species: D. anfracticirrus 42 days, D. pearsoni 23 days and D. megapharynx 32 days.

Description and life-cycle of Thrinascotrema brisbanica n. g., n. sp. (Digenea: Plagiorchiida), a parasite of the freshwater turtle Elseya latisternum from Australia, and the erection of the family Thrinascotrematidae.

A new genus and species, Thrinascotrema brisbanica, is proposed to accommodate a plagiorchiidan trematode parasitic in the stomach of the freshwater turtle Elseya latisternum. The distinctive taxonomic features of the parasite are the shape and extent of the excretory bladder, and the stenostomate arrangement of the excretory collecting ducts in the adult, cercaria and metacercaria together with a cercarial protonephridial formula of 2¿(12 + 12 + 12) + (12 + 12 + 12)¿. The life-cycle is three- host and aquatic. The pulmonate snail Glyptophysa gibbosa served as both a first and second intermediate host and tadpoles of Limnodynastes peronii, Adelotus brevis and Bufo marinus, and the snail Austropeplea lessoni also served as second intermediate hosts. Eggs were fully embryonated and infective when laid, but did not hatch until eaten by the snail. Cercariae first emerged 55 days after infection at 24-28 degrees C. They were sluggish swimmers and survived for about 48 hr. They attached firmly to the skin of snails and tadpoles on contact and began to penetrate the skin after a short exploratory migration. Metacercariae survived in snails and tadpoles for at least 3 months. It is concluded that Thrinascotrema is best placed within a new family, the Thrinascotrematidae (Digenea: Plagiorchiida), based on the unusual morphology of the excretory system.

A randomized, crossover comparison of various ventilation devices in a swine pneumothorax model.

OBJECTIVE: Bag-valve-mask devices (BVMs), manually triggered ventilators (MTVs), and automatic transport ventilators (ATVs) are three available options for out-of-hospital artificial ventilation. Use of the MTV and the ATVs has been limited by concern for causing or worsening a pneumothorax (PTX). The purpose of this study was to compare the effects of ventilation with a BVM, ATV, and MTV in a swine PTX model. METHODS: This was a randomized, crossover study. Six fasted swine (21.2-24.5 kg, mean = 23.5 kg) were sedated and paralyzed. The swine were intubated with a cuffed endotracheal tube. A lung injury was created with a hemostat under direct visualization after the pleural cavity was entered by sharp dissection. A 16-Fr Foley catheter was inserted and sealed in the pleural space at the injury site. Prior to each trial, a PTX was created by instilling 300 mL of air through the Foley catheter. Each swine underwent 10-minute ventilation trials, at a rate of 12-14 breaths/min, with BVM, MTV, and ATV by the same investigator following each trial; PTX size was determined by withdrawing air through the Foley catheter. Analysis of variance for repeated measures (alpha = 0.05) was used for statistical analysis. RESULTS: There was no difference in the extent of PTX expansion produced by ventilation with BVM (339.8 +/- 35.9 mL), MTV 327.8 +/- 28.9 mL), or ATV (321.8 +/- 22.2 ml). CONCLUSION: BVMs, MTVs, and ATVs do not differ in their effects on PTX volumes. Concern for excessive expansion of PTX by MTVs and ATVs is not supported. Prospective evaluation is warranted to determine the efficacy of these ventilation techniques.

Escherichia coli rho factor induces release of yeast RNA polymerase II but not polymerase I or III.

Purified RNA polymerase II (pol II) from the yeast Saccharomyces cerevisiae pauses without releasing at many locations during in vitro transcription. Pausing can be induced by intrinsic DNA sequence as well as by specific DNA bound proteins such as the RNA pol I termination factor, Reb1p, or lac repressor. Addition of rho termination factor from E. coli induces RNA pol II to release at all of these pause sites. Rho-induced release of pol II requires both a rho binding site in the transcript upstream of the pause sites as well as hydrolysis of ATP. In contrast, rho factor has no effect on either pausing or release by RNA pol I or III. When combined with previous observations, these results suggest that RNA pol II may terminate by a mechanism closely related to the rho-dependent mechanism of prokaryotes. In contrast, pol I and III appear to utilize a mechanism more related to the rho-independent terminators of prokaryotes.

Redescription of Hapalotrema mistroides (Monticelli, 1896) and Hapalotrema synorchis Luhman, 1935 (Digenea: Spirorchidae), with comments on other species in the genus.

Hapalotrema mistroides (Monticelli, 1896) Stiles and Hassall, 1908 and Hapalotrema synorchis Luhman, 1935 are redescribed using specimens from the loggerhead turtle. Caretta caretta (L.). The redescription of H. mistroides is based on specimens collected by Looss and described as Hapalotrema constrictum Leared, 1862 and renamed Hapalotrema loossi Price, 1934, which is now considered a junior synonym of H. mistroides. Hapalotrema orientalis Takeuti, 1942 is considered a junior synonym of Hapalotrema synorchis. The redescriptions are consistent with the originals but provide an unreported range of variation while adding new information about the reproductive systems. Reexamination of Hapalotrema dorsopora Dailey, Fast, and Balazs, 1993 confirms the presence of a reproductive system typical for the genus and the absence of a dorsal genital pore; therefore, H. dorsopora is reduced to a junior synonym of Hapalotrema mehrai Rao, 1976. Four valid species of Hapalotrema are recognized: H. mistroides. H. synorchis, H. postorchis, and H. mehrai, and a key to the species is provided.