1,324 research outputs found
Weakening of the stratospheric polar vortex by Arctic sea-ice loss
Successive cold winters of severely low temperatures in recent years have had critical social and economic impacts on the mid-latitude continents in the Northern Hemisphere. Although these cold winters are thought to be partly driven by dramatic losses of Arctic sea-ice, the mechanism that links sea-ice loss to cold winters remains a subject of debate. Here, by conducting observational analyses and model experiments, we show how Arctic sea-ice loss and cold winters in extra-polar regions are dynamically connected through the polar stratosphere. We find that decreased sea-ice cover during early winter months (November-December), especially over the Barents-Kara seas, enhances the upward propagation of planetary-scale waves with wavenumbers of 1 and 2, subsequently weakening the stratospheric polar vortex in mid-winter (January-February). The weakened polar vortex preferentially induces a negative phase of Arctic Oscillation at the surface, resulting in low temperatures in mid-latitudes.open11167174Ysciescopu
Sensitivity of Arctic warming to sea ice concentration
We examine the sensitivity of Arctic amplification (AA) to background sea ice concentration (SIC) under greenhouse warming by analyzing the data sets of the historical and Representative Concentration Pathway 8.5 runs of the Coupled Model Intercomparison Project Phase 5. To determine whether the sensitivity of AA for a given radiative forcing depends on background SIC state, we examine the relationship between the AA trend and mean SIC on moving 30 year windows from 1960 to 2100. It is found that the annual mean AA trend varies depending on the mean SIC condition. In particular, some models show a highly variable AA trend in relation to the mean SIC clearly. In these models, the AA trend tends to increase until the mean SIC reaches a critical level (i.e., 20-30%), and the maximum AA trend is almost 3 to 5 times larger than the trend in the early stage of global warming (i.e., 50-60%, 60-70%). However, the AA trend tends to decrease after that. Further analysis shows that the sensitivity of AA trend to mean SIC condition is closely related to the feedback processes associated with summer surface albedo and winter turbulent heat flux in the Arctic Ocean.1111Ysciescopu
Dark matter direct detection from new interactions in models with spin-two mediators
We consider models where a massive spin-two resonance acts as the mediator between Dark Matter (DM) and the SM particles through the energy-momentum tensor. We examine the effective theory for fermion, vector and scalar DM generated in these models and find novel types of DM-SM interaction never considered before. We identify the effective interactions between DM and the SM quarks when the mediator is integrated out, and match them to the gravitational form factors relevant for spin-independent DM-nucleon scattering. We also discuss the interplay between DM relic density conditions, direct detection bounds and collider searches for the spin-two mediator
Triphasic Computed Tomography Enterography with Polyethylene Glycol to Detect Renal Cell Carcinoma Metastases to the Small Bowel
Enteroclysis was first used to diagnose small bowel obstruction in 1996. However, nasojejunal intubation required during enteroclysis causes discomfort to the patient. Triphasic computed tomography (CT) enterography, a noninvasive procedure that does not require intubation, was found to be an efficient method to diagnose small bowel lesions. We describe our experience of using triphasic CT enterography with polyethylene glycol (PEG) for diagnosing renal cell carcinoma (RCC) metastases to the small intestine. RCC can metastasize to many organs and can cause variable clinical presentations. We report the case of a 56-year-old man with RCC who had psoas muscle involvement and lung metastasis. The patient presented with melena and intermittent abdominal pain. Two conventional CT and small bowel series examinations had shown no obstructive lesion in the small intestine. However, triphasic CT enterography with PEG detected two enhanced masses suggestive of small bowel metastasis. The patient underwent laparotomy and segmental resection of the jejunum with primary anastomosis. Histologic examination was compatible with RCC. This is the first report where RCC metastasis to the small bowel was diagnosed using triphasic CT enterography. Our study emphasizes the importance of triphasic CT enterography in cases of obscure gastrointestinal bleeding, especially in patients suspected of having small bowel metastasis
Early pneumothorax as a feature of response to crizotinib therapy in a patient with ALK rearranged lung adenocarcinoma.
Background: Single arm phase 1 and 2 studies on Crizotinib in ALK-positive patients so far have shown rapid and durable responses. Spontaneous pneumothoraces as a result of response to anti-cancer therapy are rare in oncology but have been documented in a number of tumour types including lung cancer. This includes cytotoxic chemotherapy as well as molecular targeted agents such as gefitinib and Bevacizumab. These often require chest drain insertion or surgical intervention with associated morbidity and mortality. They have also been associated with response to treatment. This is the first report we are aware of documenting pneumothorax as response to crizotinib therapy.Case presentation: A 48-year-old Caucasian male presented with a Stage IV, TTF1 positive, EGFR wild-type adenocarcinoma of the lung. He received first line chemotherapy with three cycles of cisplatin-pemetrexed chemotherapy with a differential response, and then second-line erlotinib for two months before further radiological evidence of disease progression. Further analysis of his diagnostic specimen identified an ALK rearrangement by fluorescence in situ hybridization (FISH). He was commenced on crizotinib therapy 250 mg orally twice daily. At his 4-week assessment he had a chest radiograph that identified a large left-sided pneumothorax with disease response evident on the right. Chest CT confirmed a 50% left-sided pneumothorax on a background of overall disease response. A chest tube was inserted with complete resolution of the pneumothorax that did not recur following its removal.Conclusion: Our case demonstrates this potential complication of crizotinib therapy and we therefore recommend that pneumothorax be considered in patients on crizotinib presenting with high lung metastatic burden and with worsening dyspnoea. © 2013 Gennatas et al.; licensee BioMed Central Ltd
A molecular insight into algal-oomycete warfare : cDNA analysis of Ectocarpus siliculosus infected with the basal oomycete Eurychasma dicksonii
Peer reviewedPublisher PD
Daratumumab plus bortezomib, cyclophosphamide, and dexamethasone in Asian patients with newly diagnosed AL amyloidosis: subgroup analysis of ANDROMEDA
Subcutaneous daratumumab plus bortezomib/cyclophosphamide/dexamethasone (VCd; D-VCd) improved outcomes versus VCd for patients with newly diagnosed immunoglobulin light-chain (AL) amyloidosis in the phase 3 ANDROMEDA study. We report a subgroup analysis of Asian patients (Japan; Korea; China) from ANDROMEDA. Among 388 randomized patients, 60 were Asian (D-VCd, n = 29; VCd, n = 31). At a median follow-up of 11.4 months, the overall hematologic complete response rate was higher for D-VCd versus VCd (58.6% vs. 9.7%; odds ratio, 13.2; 95% confidence interval [CI], 3.3–53.7; P < 0.0001). Six-month cardiac and renal response rates were higher with D-VCd versus VCd (cardiac, 46.7% vs. 4.8%; P = 0.0036; renal, 57.1% vs. 37.5%; P = 0.4684). Major organ deterioration progression-free survival (MOD-PFS) and major organ deterioration event-free survival (MOD-EFS) were improved with D-VCd versus VCd (MOD-PFS: hazard ratio [HR], 0.21; 95% CI, 0.06–0.75; P = 0.0079; MOD-EFS: HR, 0.16; 95% CI, 0.05–0.54; P = 0.0007). Twelve deaths occurred (D-VCd, n = 3; VCd, n = 9). Twenty-two patients had baseline serologies indicating prior hepatitis B virus (HBV) exposure; no patient experienced HBV reactivation. Although grade 3/4 cytopenia rates were higher than in the global safety population, the safety profile of D-VCd in Asian patients was generally consistent with the global study population, regardless of body weight. These results support D-VCd use in Asian patients with newly diagnosed AL amyloidosis. ClinicalTrials.gov Identifier: NCT03201965
Genome-wide analyses for personality traits identify six genomic loci and show correlations with psychiatric disorders
Personality is influenced by genetic and environmental factors1
and associated with mental health. However, the underlying
genetic determinants are largely unknown. We identified six
genetic loci, including five novel loci2,3, significantly associated
with personality traits in a meta-analysis of genome-wide
association studies (N = 123,132–260,861). Of these genomewide
significant loci, extraversion was associated with variants
in WSCD2 and near PCDH15, and neuroticism with variants
on chromosome 8p23.1 and in L3MBTL2. We performed a
principal component analysis to extract major dimensions
underlying genetic variations among five personality traits
and six psychiatric disorders (N = 5,422–18,759). The first
genetic dimension separated personality traits and psychiatric
disorders, except that neuroticism and openness to experience
were clustered with the disorders. High genetic correlations
were found between extraversion and attention-deficit–
hyperactivity disorder (ADHD) and between openness and
schizophrenia and bipolar disorder. The second genetic
dimension was closely aligned with extraversion–introversion
and grouped neuroticism with internalizing psychopathology
(e.g., depression or anxiety)
Mapping interactions with the chaperone network reveals factors that protect against tau aggregation.
A network of molecular chaperones is known to bind proteins ('clients') and balance their folding, function and turnover. However, it is often unclear which chaperones are critical for selective recognition of individual clients. It is also not clear why these key chaperones might fail in protein-aggregation diseases. Here, we utilized human microtubule-associated protein tau (MAPT or tau) as a model client to survey interactions between ~30 purified chaperones and ~20 disease-associated tau variants (~600 combinations). From this large-scale analysis, we identified human DnaJA2 as an unexpected, but potent, inhibitor of tau aggregation. DnaJA2 levels were correlated with tau pathology in human brains, supporting the idea that it is an important regulator of tau homeostasis. Of note, we found that some disease-associated tau variants were relatively immune to interactions with chaperones, suggesting a model in which avoiding physical recognition by chaperone networks may contribute to disease
Cysteamine broadly improves the anti-plasmodial activity of artemisinins against murine blood stage and cerebral malaria
- …