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Limiting global warming to 2 °C requires urgent action on land-based mitigation. This study evaluates the biogeochemical and biogeophysical implications of two alternative land-based mitigation scenarios that aim to achieve the same radiative forcing. One scenario is primarily driven by bioenergy expansion (SSP226Lu-BIOCROP), while the other involves re/afforestation (SSP126Lu-REFOREST). We find that overall, SSP126Lu-REFOREST is a more efficient strategy for removing CO2 from the atmosphere by 2100, resulting in a net carbon sink of 242 ~ 483 PgC with smaller uncertainties compared to SSP226Lu-BIOCROP, which exhibits a wider range of -78 ~ 621 PgC. However, SSP126Lu-REFOREST leads to a relatively warmer planetary climate than SSP226Lu-BIOCROP, and this relative warming can be intensified in certain re/afforested regions where local climates are not favorable for tree growth. Despite the cooling effect on a global scale, SSP226Lu-BIOCROP reshuffles regional warming hotspots, amplifying summer temperatures in vulnerable tropical regions such as Central Africa and Southeast Asia. Our findings highlight the need for strategic land use planning to identify suitable regions for re/afforestation and bioenergy expansion, thereby improving the likelihood of achieving the intended climate mitigation outcomes.
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Toxoplasma gondii relies heavily on the de novo pyrimidine biosynthesis pathway for fueling the high uridine-5'-monophosphate (UMP) demand during parasite growth. The third step of de novo pyrimidine biosynthesis is catalyzed by dihydroorotase (DHO), a metalloenzyme that catalyzes the reversible condensation of carbamoyl aspartate to dihydroorotate. Here, functional analyses of TgDHO reveal that tachyzoites lacking DHO are impaired in overall growth due to decreased levels of UMP, and the noticeably growth restriction could be partially rescued after supplementation with uracil or high concentrations of L-dihydroorotate in vitro. When pyrimidine salvage pathway is disrupted, both DHOH35A and DHOD284E mutant strains proliferated much slower than DHO-expressing parasites, suggesting an essential role of both TgDHO His35 and Asp284 residues in parasite growth. Additionally, DHO deletion causes the limitation of bradyzoite growth under the condition of uracil supplementation or uracil deprivation. During the infection in mice, the DHO-deficient parasites are avirulent, despite the generation of smaller tissue cysts. The results reveal that TgDHO contributes to parasite growth both in vitro and in vivo. The significantly differences between TgDHO and mammalian DHO reflect that DHO can be exploited to produce specific inhibitors targeting apicomplexan parasites. Moreover, potential DHO inhibitors exert beneficial effects on enzymatic activity of TgDHO and T. gondii growth in vitro. In conclusion, these data highlight the important role of TgDHO in parasite growth and reveal that it is a promising anti-parasitic target for future control of toxoplasmosis.
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Parasitos , Toxoplasma , Animais , Camundongos , Di-Hidro-Orotase , Pirimidinas/farmacologia , Uracila , Uridina Monofosfato , MamíferosRESUMO
SignificanceStream/river carbon dioxide (CO2) emission has significant spatial and seasonal variations critical for understanding its macroecosystem controls and plumbing of the terrestrial carbon budget. We relied on direct fluvial CO2 partial pressure measurements and seasonally varying gas transfer velocity and river network surface area estimates to resolve reach-level seasonal variations of the flux at the global scale. The percentage of terrestrial primary production (GPP) shunted into rivers that ultimately contributes to CO2 evasion increases with discharge across regions, due to a stronger response in fluvial CO2 evasion to discharge than GPP. This highlights the importance of hydrology, in particular water throughput, in terrestrial-fluvial carbon transfers and the need to account for this effect in plumbing the terrestrial carbon budget.
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14,14'-Bidibenzo[a,j]anthracenes (BDBAs) were prepared by iridium-catalyzed annulation of 5,5'-biterphenylene with alkynes. The molecular geometries of overcrowded BDBAs were verified by X-ray crystallography. The two dibenzo[a,j]anthryl moieties are connected through the sterically hindered 14 positions, resulting in highly distorted molecular halves. The conformation with a small twist angle between two molecular halves can minimize steric conflicts between the substituents at 1 and 13 positions and the carbon atoms of the central axis, as well as steric clashes between those substituents. One such example is octafluoro-substituted BDBA, where the interplanar angle between two anthryl moieties is approximately 31° (currently the lowest reported value, cf. 81° in 9,9'-bianthracene). The intramolecular interactions and electronic couplings between two molecular halves resulted in upfield 1H NMR signals, redshifted absorption and emission bands, and a reduced HOMO-LUMO gap. Photodynamic investigations on BDBAs indicated that the formation of the conventional symmetry-breaking charge transfer (SBCT) state was suspended by restricted rocking around the central C-C bond. Such a mechanism associated with this highly constrained conformation was examined for the first time.
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A new series of biaryls, bi-linear-terphenylenes (BLTPs), were prepared using the tert-butyllithium-mediated cyclization as the key synthetic step. The three-dimensional structures of the studied compounds were verified using X-ray crystallography and DFT calculations. Tetraaryl(ethynyl)-substituted BLTPs are highly crowded molecules, and the internal rotation around the central C-C bond is restricted due to a high barrier (>50â kcal/mol). These structures contain several aryl/terphenylenyl/aryl sandwiches, where the through-space π-π (TSPP) interactions are strongly reflected in the shielding of 1 H NMR chemical shifts, reduction of oxidation potentials, increasing aromaticity of the central six-membered ring and decreasing antiaromaticity of the four-membered rings in a terphenylenyl moiety based on NICS(0) and iso-chemical shielding surfaces. Despite the restricted C-C bond associated intramolecular TSPP interactions for BLTPs in the ground state, to our surprise, the electronic coupling between two linear terphenylenes (LTPs) in BLTPs in the excited state is weak, so that the excited-state behavior is dominated by the corresponding monomeric LTPs. In other words, all BLTPs undergo ultrafast relaxation dynamics via strong exciton-vibration coupling, acting as a blue-light absorber with essentially no emission.
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The first amidation of carbazoles at the N9 position via palladium-catalyzed hydroamination of isocyanates is demonstrated. This simple, general and efficient method could deliver a wide range of carbazole-N-carboxamides in up to 99% yield. The salient features of this transformation include simple conditions with no need for a strong base, high chemo- and regio-selectivities and good functional group tolerance. In particular, this work-up-free and chromatography-free protocol is time-saving, cost-effective and user-friendly.
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Out of the total cases of cervical cancer, brain metastases (BMs) are relatively rare, with an estimated incidence rate of 0.63% (range: 0.1%-2.2%). Additionally, BMs prognosis remains poor, and the average patient survival time following a BM diagnosis is 3 to 5 months. Few studies have addressed the effect of programmed cell death-1 inhibitors against BMs in cervical cancer, although they are an established option for recurrent/metastatic disease. Hence, we report a case involving a 54-year-old post-surgery patient with cervical cancer with a body mass index of 19.5 kg/m2 and Eastern Collaborative Oncology Group (ECOG) performance status of 3; the disease recurred with BMs 1 year later. Intensity-modulated radiation therapy concurrent with temozolomide and bevacizumab was initiated, following which zimberelimab immunotherapy combined with anlotinib was administered to extend tumor control. The patient had a progression-free survival duration of 10 months, the tumor response was assessed as a partial response based on the evaluation criteria for solid tumors (RECIST1.1), and the ECOG status improved to 1 after therapy. These findings suggest that immunotherapy-based combination therapy following radiotherapy may be a good choice for patients with cervical cancer and BMs.
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Neoplasias Encefálicas , Neoplasias do Colo do Útero , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/tratamento farmacológico , Recidiva Local de Neoplasia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Anticorpos Monoclonais Humanizados/uso terapêuticoRESUMO
Toxoplasma gondii is a widespread protozoan parasite approximately infecting one-third of the world population and can cause serious public health problems. In this study, we investigated the protective effect of the attenuated vaccine Pru:Δcdpk2 against acute toxoplasmosis and explored the underlying immune mechanisms of the protection in pigs. The systemic T-cell and natural killer (NK) cell responses were analyzed, including kinetics, phenotype, and multifunctionality (interferon [IFN]-γ, tumor necrosis factor [TNF]-α), and the IFN-γ levels were analyzed in PBMCs. Our results showed that T. gondii-specific antibodies were induced by Pru:Δcdpk2. After challenging with RH, the antibodies were able to respond quickly in the immunized group, and the expression level was significantly higher than that in the unimmunized group. The expression level of IFN-γ significantly increased after vaccination, and the CD3+ γδ-, NK, and CD3+ γδ+ cell subsets also significantly increased. At the same time, functional analysis indicated that these cells were polarized toward a Th1 phenotype, showing the ability to secrete IFN-γ and TNF-α. The CD4+CD8α-T cell population exhibited a higher frequency of IFN-γ+ producing cells compared with the CD4-CD8α+ and CD4+CD8α+ cell populations during the early days of vaccination. Our results indicated that the attenuated vaccine could induce the expression of NK, γδ, and CD3αß cells in pigs, and IFN-γ and TNF-α secreted by these cells are important for resistance to T. gondii infection.
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Inflammatory bowel diseases (IBDs) are prevalent and debilitating diseases with limited clinical treatment strategies. Mesenchymal stem cell (MSCs) are pluripotent stem cells with self-renewal capability and multiple immunomodulatory effects, which make them a promising therapeutic approach for IBDs. Thus, optimization of MSCs regimes is crucial for their further clinical application. Wogonin, a flavonoid-like compound with extensive immunomodulatory and adjuvant effects, has been investigated as a potential pretreatment for MSCs in IBD treatment. In this study, we employed the DSS-induced acute colitis mouse model to compare the therapeutic effectiveness of MSCs in pretreated with or without wogonin and further explore the underlying mechanism. Compared to untreated MSCs, MSCwogonin (pretreated with wogonin) showed greater effectiveness in the treatment of colitis. Further experiments revealed that wogonin treatment activated the AKT signaling pathway, resulting in higher cellular glycolysis. Inhibition of AKT phosphorylation by perifosine not only decreased glycolysis but impaired the therapeutic efficiency of MSCwogonin. Consistent with these results, qPCR data indicated that wogonin treatment induced the expression of immunomodulatory molecules IL-10, IDO, and AGR1, which were reduced by perifosine. Together, our data demonstrated that wogonin preconditioning strategy further augmented the therapeutic efficacy of MSCs via promoting glycolysis, which should be a promising strategy for optimizing MSCs therapy in IBDs.
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Colite , Flavanonas , Glicólise , Células-Tronco Mesenquimais , Camundongos Endogâmicos C57BL , Animais , Flavanonas/farmacologia , Flavanonas/administração & dosagem , Camundongos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Colite/tratamento farmacológico , Colite/induzido quimicamente , Glicólise/efeitos dos fármacos , Modelos Animais de Doenças , Transplante de Células-Tronco Mesenquimais/métodos , Masculino , Transdução de Sinais/efeitos dos fármacos , Sulfato de DextranaRESUMO
Polymer electrolytes play a crucial role in advancing rechargeable magnesium batteries (RMBs) owing to their exceptional characteristics, including high flexibility, superior interface compatibility, broad electrochemical stability window, and enhanced safety features. Despite these advantages, research in this domain remains nascent, plagued by single preparation approaches and challenges associated with the compatibility between polymer electrolytes and Mg metal anode. In this study, we present a novel synthesis strategy to fabricate a glycerol α,α'-diallyl ether-3,6-dioxa-1,8-octanedithiol-based composite gel polymer electrolyte supported by glass fiber substrate (GDT@GF CGPE) through anion modification and thiol-ene click chemistry polymerization. The developed route exhibits novelty and high efficiency, leading to the production of GDT@GF CGPEs featuring exceptional mechanical properties, heightened ionic conductivity, elevated Mg2+ transference number, and commendable compatibility with Mg anode. The assembled modified Mo6S8||GDT@GF||Mg cells exhibit outstanding performance across a wide temperature range and address critical safety concerns, showcasing the potential for applications under extreme conditions. Our innovative preparation strategy offers a promising avenue for the advancement of polymer electrolytes in high-performance rechargeable magnesium batteries, while also opens up possibilities for future large-scale applications and the development of flexible electronic devices.
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Catalyst design has traditionally focused on rigid structural elements to prevent conformational flexibility. Ishihara's elegant design of conformationally flexible C2-symmetric iodoarenes, a new class of privileged organocatalysts, for the catalytic asymmetric dearomatization (CADA) of naphthols is a notable exception. Despite the widespread use of the Ishihara catalysts for CADAs, the reaction mechanism remains the subject of debate, and the mode of asymmetric induction has not been well established. Here, we report an in-depth computational investigation of three possible mechanisms in the literature. Our results, however, reveal that this reaction is best rationalized by a fourth mechanism called "proton-transfer-coupled-dearomatization (PTCD)", which is predicted to be strongly favored over other competing pathways. The PTCD mechanism is consistent with a control experiment and further validated by applying it to rationalize the enantioselectivities. Oxidation of the flexible I(I) catalyst to catalytic active I(III) species induces a defined C2-symmetric helical chiral environment with a delicate balance between flexibility and rigidity. A match/mismatch effect between the active catalyst and the substrate's helical shape in the dearomatization transition states was observed. The helical shape match allows the active catalyst to adapt its conformation to maximize attractive noncovalent interactions, including I(III)···O halogen bond, N-H···O hydrogen bond, and π···π stacking, to stabilize the favored transition state. A stereochemical model capable of rationalizing the effect of catalyst structural variation on the enantioselectivities is developed. The present study enriches our understanding of how flexible catalysts achieve high stereoinduction and may serve as an inspiration for the future exploration of conformational flexibility for new catalyst designs.
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Essential Tremor (ET) is a prevalent neurological disease characterized by an 8-10 Hz action tremor. Molecular mechanisms of ET remain poorly understood. Clinical data suggest the importance of the cerebellum in disease pathophysiology, and pathological studies indicate Purkinje Cells (PCs) incur damage. Our recent cerebellar cortex and PC-specific transcriptome studies identified alterations in calcium (Ca2+) signaling pathways that included ryanodine receptor type 1 (RyR1) in ET. RyR1 is an intracellular Ca2+ release channel located on the Endoplasmic Reticulum (ER), and in cerebellum is predominantly expressed in PCs. Under stress conditions, RyR1 undergoes several post-translational modifications (protein kinase A [PKA] phosphorylation, oxidation, nitrosylation), coupled with depletion of the channel-stabilizing binding partner calstabin1, which collectively characterize a "leaky channel" biochemical signature. In this study, we found markedly increased PKA phosphorylation at the RyR1-S2844 site, increased RyR1 oxidation and nitrosylation, and calstabin1 depletion from the RyR1 complex in postmortem ET cerebellum. Decreased calstabin1-RyR1-binding affinity correlated with loss of PCs and climbing fiber-PC synapses in ET. This 'leaky' RyR1 signature was not seen in control or Parkinson's disease cerebellum. Microsomes from postmortem cerebellum demonstrated excessive ER Ca2+ leak in ET vs. controls, attenuated by channel stabilization. We further studied the role of RyR1 in tremor using a mouse model harboring a RyR1 point mutation that mimics constitutive site-specific PKA phosphorylation (RyR1-S2844D). RyR1-S2844D homozygous mice develop a 10 Hz action tremor and robust abnormal oscillatory activity in cerebellar physiological recordings. Intra-cerebellar microinfusion of RyR1 agonist or antagonist, respectively, increased or decreased tremor amplitude in RyR1-S2844D mice, supporting a direct role of cerebellar RyR1 leakiness for tremor generation. Treating RyR1-S2844D mice with a novel RyR1 channel-stabilizing compound, Rycal, effectively dampened cerebellar oscillatory activity, suppressed tremor, and normalized cerebellar RyR1-calstabin1 binding. These data collectively support that stress-associated ER Ca2+ leak via RyR1 may contribute to tremor pathophysiology.
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Cálcio , Canal de Liberação de Cálcio do Receptor de Rianodina , Humanos , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Cálcio/metabolismo , Tremor/metabolismo , Cerebelo/metabolismo , Retículo Endoplasmático/metabolismo , Músculo Esquelético/metabolismoRESUMO
Ferroptosis, triggered by discoordination of iron, thiols and lipids, leads to the accumulation of 15-hydroperoxy (Hp)-arachidonoyl-phosphatidylethanolamine (15-HpETE-PE), generated by complexes of 15-lipoxygenase (15-LOX) and a scaffold protein, phosphatidylethanolamine (PE)-binding protein (PEBP)1. As the Ca2+-independent phospholipase A2ß (iPLA2ß, PLA2G6 or PNPLA9 gene) can preferentially hydrolyze peroxidized phospholipids, it may eliminate the ferroptotic 15-HpETE-PE death signal. Here, we demonstrate that by hydrolyzing 15-HpETE-PE, iPLA2ß averts ferroptosis, whereas its genetic or pharmacological inactivation sensitizes cells to ferroptosis. Given that PLA2G6 mutations relate to neurodegeneration, we examined fibroblasts from a patient with a Parkinson's disease (PD)-associated mutation (fPDR747W) and found selectively decreased 15-HpETE-PE-hydrolyzing activity, 15-HpETE-PE accumulation and elevated sensitivity to ferroptosis. CRISPR-Cas9-engineered Pnpla9R748W/R748W mice exhibited progressive parkinsonian motor deficits and 15-HpETE-PE accumulation. Elevated 15-HpETE-PE levels were also detected in midbrains of rotenone-infused parkinsonian rats and α-synuclein-mutant SncaA53T mice, with decreased iPLA2ß expression and a PD-relevant phenotype. Thus, iPLA2ß is a new ferroptosis regulator, and its mutations may be implicated in PD pathogenesis.
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Ferroptose/fisiologia , Fosfolipases A2 do Grupo VI/metabolismo , Animais , Araquidonato 15-Lipoxigenase/metabolismo , Modelos Animais de Doenças , Feminino , Fosfolipases A2 do Grupo VI/fisiologia , Humanos , Ferro/metabolismo , Leucotrienos/metabolismo , Metabolismo dos Lipídeos/fisiologia , Peróxidos Lipídicos/metabolismo , Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Doença de Parkinson/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Fosfolipases/metabolismo , Fosfolipídeos/metabolismo , Ratos , Ratos Endogâmicos LewRESUMO
The cerebellum plays an important role in movement disorders, specifically in symptoms of ataxia, tremor, and dystonia. Understanding the physiological signals of the cerebellum contributes to insights into the pathophysiology of these movement disorders and holds promise in advancing therapeutic development. Non-invasive techniques such as electroencephalogram and magnetoencephalogram can record neural signals with high temporal resolution at the millisecond level, which is uniquely suitable to interrogate cerebellar physiology. These techniques have recently been implemented to study cerebellar physiology in healthy subjects as well as individuals with movement disorders. In the present review, we focus on the current understanding of cerebellar physiology using these techniques to study movement disorders.
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Ataxia Cerebelar , Distúrbios Distônicos , Transtornos dos Movimentos , Humanos , Cerebelo/fisiologia , TremorRESUMO
Recent findings in animals have challenged the traditional view of the cerebellum solely as the site of motor control, suggesting that the cerebellum may also be important for learning to predict reward from trial-and-error feedback. Yet, evidence for the role of the cerebellum in reward learning in humans is lacking. Moreover, open questions remain about which specific aspects of reward learning the cerebellum may contribute to. Here we address this gap through an investigation of multiple forms of reward learning in individuals with cerebellum dysfunction, represented by cerebellar ataxia cases. Nineteen participants with cerebellar ataxia and 57 age- and sex-matched healthy controls completed two separate tasks that required learning about reward contingencies from trial-and-error. To probe the selectivity of reward learning processes, the tasks differed in their underlying structure: while one task measured incremental reward learning ability alone, the other allowed participants to use an alternative learning strategy based on episodic memory alongside incremental reward learning. We found that individuals with cerebellar ataxia were profoundly impaired at reward learning from trial-and-error feedback on both tasks, but retained the ability to learn to predict reward based on episodic memory. These findings provide evidence from humans for a specific and necessary role for the cerebellum in incremental learning of reward associations based on reinforcement. More broadly, the findings suggest that alongside its role in motor learning, the cerebellum likely operates in concert with the basal ganglia to support reinforcement learning from reward.
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INTRODUCTION: Posterior reversible encephalopathy syndrome is a rare neurologic complication that can occur under immunosuppressive therapy with CNI after organ transplantation. METHODS: We retrospectively reviewed medical records of 545 patients who underwent lung transplantation between 2012 and 2019. Within this group, we identified 30 patients with neurological symptoms typical of PRES and compared the characteristics of patients who were diagnosed with PRES (n = 11) to those who were not (n = 19). RESULTS: The incidence of PRES after lung transplantation was 2%. Notably, 73% of the patients with PRES were female and the mean age was 39.2. Seizure (82% vs. 21%, p = .002) was the most common neurological presentation. The risk of developing PRES was significantly associated with age (OR = .92, p < .0001) and having cystic fibrosis (CF) (OP = 10.1, p < .0001). Creatinine level (1.9 vs. 1.1 mg/dl, p = .047) and tacrolimus trough level (19.4 vs. 16.5 ng/ml, p = .048) within 1 week prior to neurological symptoms were significantly higher in patients with PRES. CONCLUSION: Renal insufficiency and high tacrolimus levels are associated with PRES. A change of immunosuppressive drug should be done after confirmed PRES diagnosis or immediately in case of severe neurological dysfunction to improve neurological outcomes and minimize the risk of early allograft rejection.
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Transplante de Pulmão , Síndrome da Leucoencefalopatia Posterior , Humanos , Feminino , Adulto , Masculino , Tacrolimo/efeitos adversos , Síndrome da Leucoencefalopatia Posterior/diagnóstico , Síndrome da Leucoencefalopatia Posterior/etiologia , Estudos Retrospectivos , Transplante de Pulmão/efeitos adversos , Fatores de RiscoRESUMO
BACKGROUND: The treatment of acute pancreatitis (AP) induced by hypertriglyceridemia (HTG) remains controversial with regard to plasmapheresis vs conventional treatment. We reviewed relevant articles to explore the efficacy of plasmapheresis in the management of HTG-induced AP. METHODS: We systematically reviewed studies that compared plasmapheresis with conventional treatment for HTG-induced AP using three databases: PubMed, Embase, and Cochrane Library, as well as relevant references. The primary outcomes were 24 h triglyceride reduction rate and in-hospital mortality. RESULTS: A total of 791 articles were retrieved. Finally, 15 observational studies (1080 participants) were included, most of which were historical cohort studies. Compared with conventional treatment, plasmapheresis assisted in the reduction of serum triglyceride (TG) levels in the first 24 h after hospital admission (standardized mean difference [SMD]: 0.58; 95% confidence interval [CI]: 0.17 to 0.99; P = 0.005). However, it resulted in increased hospitalization costs (thousand yuan) (weighted mean difference [WMD]: 24.32; 95% CI: 12.96 to 35.68; P < 0.001). With regard to in-hospital mortality, although the mortality rate in the plasmapheresis group was higher than that in the conventional treatment group (relative risk [RR]: 1.74; 95% CI: 1.03 to 2.94; P = 0.038), the result was disturbed by confounding factors as per the subgroup and sensitivity analysis, as well as trial sequential analysis (TSA). No significant differences were found in other outcomes, including systematic complications, local complications, the requirement for surgery, and hospitalization duration. CONCLUSION: The effect of plasmapheresis in HTG-induced AP is not superior to that of conventional treatment, even resulting in a greater economic burden to patients and health care system. High quality randomized control trials are required to obtain a more a definitive understanding of this issue.
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Hipertrigliceridemia , Pancreatite , Humanos , Pancreatite/complicações , Pancreatite/terapia , Doença Aguda , Plasmaferese/métodos , Hipertrigliceridemia/complicações , Hipertrigliceridemia/terapia , Triglicerídeos , Estudos RetrospectivosRESUMO
At present, the reconstruction error of optical fiber shape sensing is commonly represented by Euclidean distance error. However, the Euclidian error of shape reconstruction will be dependent on the shape complexity, which depends on length, curvature and torsion. In this paper, we establish a reconstruction error model of distributed shape sensing in optical frequency domain reflectometry (OFDR) based on the Frenet-Serret frame and the error delivering theory, which illustrates the relationship between the reconstruction error and parameters such as curvature, torsion, fiber length and strain measurement error. We experimentally verify the feasibility and applicability of the proposed reconstruction error model by distributed optical fiber shape sensing system based on OFDR. The proposed reconstruction error model can provide a prediction of the maximal reconstruction error when the estimated range of curvature, torsion, fiber length of a shape needs to be reconstructed and strain measurement errors of OFDR system are known. It is very useful to judge whether the shape reconstruction error meets the requirement according to the shape to be reconstructed.
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Enhanced cerebellar oscillations have recently been identified in essential tremor (ET) patients as a key pathophysiological change. Since ET is considered a heterogeneous group of diseases, we investigated whether cerebellar oscillations differ in ET subtypes (familial vs. sporadic). This study aims to determine cerebellar physiology in familial and sporadic ET. Using surface electroencephalogram, we studied cerebellar physiology in 40 ET cases (n = 22 familial and n = 18 sporadic) and 20 age-matched controls. Both familial and sporadic ET cases had an increase in the intensity of cerebellar oscillations when compared to controls. Interestingly, cerebellar oscillations correlated with tremor severity in familial ET but not in sporadic ET. Our study demonstrated that ET cases have enhanced cerebellar oscillations, and the different relationships between cerebellar oscillations and tremor severity in familial and sporadic ET suggest diverse cerebellar pathophysiology.
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Tremor Essencial , Cerebelo , Eletroencefalografia , Humanos , Modalidades de Fisioterapia , TremorRESUMO
BACKGROUND: Norovirus is highly diverse and constant surveillance is essential for the prevention and control of norovirus gastroenteritis. METHODS: From 2015 to 2019, fecal samples were collected from sporadic cases and outbreaks of acute gastroenteritis reported to Sichuan center for disease control and prevention. Sewage samples were collected from a wastewater treatment plant in Sichuan. All samples were tested for norovirus by real-time reverse transcription polymerase chain reaction. Norovirus-positive clinical samples were sequenced by Sanger sequencing. Sewage samples were sequenced by amplicon and virome sequencing. RESULTS: A total of 1462 fecal samples were collected and 11 different norovirus genotypes were detected. GII.4 Sydney 2012[P31] and GII.3[P12] were the dominant genotypes in sporadic cases whereas GII.2[P16] and GII.17[P17] were the dominant genotypes in outbreaks. GII.3 was predominant in children 0-6 months of age during spring and summer, while GII.4 was predominant in children older than 6 months and in the autumn. The detection rate of GII.17[P17] increased with age. In sewage, 16 genotypes were detected. GII.3, GII.4, GI.1, and GI.2 were the dominant genotypes. CONCLUSION: This study demonstrated that multiple norovirus genotypes co-circulate in Sichuan. It is vital to continuously trace the genetic diversity of norovirus to give a future perspective on surveillance needs and guide vaccine design and policy decisions.