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Stacking orders provide a unique way to tune the properties of two-dimensional materials. Recently, ABCB-stacked tetralayer graphene has been predicted to possess atypical elemental ferroelectricity arising from its symmetry breaking but has been experimentally explored very little. Here, we observe pronounced nonlinear optical second-harmonic generation (SHG) in ABCB-stacked tetralayer graphene while absent in both ABAB- and ABCA-stacked allotropes. Our results provide direct evidence of symmetry breaking in ABCB-stacked tetralayer graphene. The remarkable contrast in the SHG spectra of tetralayer graphene allows straightforward identification of ABCB domains from the other two kinds of stacking order and facilitates the characterization of their crystalline orientation. The employed SHG technique serves as a convenient tool for exploring the intriguing physics and novel nonlinear optics in ABCB-stacked graphene, where spontaneous polarization and intrinsically gapped flat bands coexist. Our results establish ABCB-stacked graphene as a unique platform for studying the rare ferroelectricity in noncentrosymmetric elemental structures.
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BACKGROUND: The triglyceride-glucose (TyG) index serves as a reliable proxy for insulin resistance (IR). IR has been linked to heightened incidence, prevalence, or severity of chronic obstructive pulmonary disease (COPD) and asthma. Prior research indicates that critically ill patients are prone to developing IR. Nevertheless, few studies have delved into the correlation between IR and all-cause mortality in critically ill patients with COPD and asthma. Therefore, the aim of this study is to explore the association between the TyG index and all-cause mortality in patients with COPD and asthma, with the goal of assessing the impact of IR on the prognosis of this patient population. METHODS: This is a retrospective study, and all data are from the Medical Information Mart for Intensive Care IV (MIMIC-IV) critical care database. This study included 684 ICU patients with COPD and asthma and divided them into quartiles based on TyG index levels. The primary outcomes of this study were all-cause mortality during follow-up, encompassing mortality at 30 days, 90 days, and 180 days. The Kaplan-Meier analysis was used to compare all-cause mortality among the above four groups. Cox proportional hazards analyses were performed to examine the association between TyG index and all-cause mortality in critically ill patients with COPD and asthma. Restricted cubic spline analysis was used to assess potential nonlinear association between the TyG index and the primary outcome. RESULTS: A total of 684 patients (53.9% female) were included. The 90-days all-cause mortality rate and 180-days all-cause mortality were 11.7% and 12.3%, respectively. Kaplan-Meier analysis revealed a significant association between the TyG index and both 90-days all-cause mortality (log-rank p = .039) and 180-days all-cause mortality (log-rank p = .017). Cox proportional hazards analysis revealed a significant association between the TyG index and 90-days all-cause mortality in both the unadjusted model (HR, 1.30 [95% CI 1.08-1.57] p = .005) and the model adjusted for age, gender, and diabetes (HR, 1.38 [95% CI 1.15-1.67] p < .001). Similarly, the TyG index was associated with 180-days all-cause mortality in the unadjusted model (HR, 1.30 [95% CI 1.09-1.56] p = .004) and the model adjusted for age, sex, and diabetes (HR, 1.38 [95% CI 1.15-1.66] p < .001). The restricted cubic splines (RCS) regression model indicated a significant nonlinear association between the TyG index and both 90-days and 180-days all-cause mortality. Specifically, TyG index >4.8 was associated with an increased risk of mortality at both 90 days and 180 days. CONCLUSIONS: In summary, our results extend the utility of the TyG index to critically ill patients with COPD and asthma. Our study shows that the TyG index is a potential predictor of all-cause mortality in critically ill patients with COPD and asthma. In addition, in patients with a TyG index exceeding 4.8, there was a heightened risk of mortality. Measuring the TyG index may help with risk stratification and prognosis prediction in critically ill patients with COPD and asthma. Further prospective studies are needed to confirm our findings.
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Asma , Diabetes Mellitus , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Femenino , Masculino , Estudios Retrospectivos , Enfermedad Crítica , GlucosaRESUMEN
The concise, collective, and asymmetric total syntheses of four schizozygane alkaloids, which feature a "Pan lid"-like hexacyclic core scaffold bearing up to six continuous stereocenters, including two quaternary ones, are described. A new method of dearomative cyclization of cyclopropanol onto the indole ring at C2 was developed to build the ABCF ring system of the schizozygane core with a ketone group. Another key skeleton-building reaction, the Heck/carbonylative lactamization cascade, ensured the rapid assembly of the hexacyclic schizozygane core and concurrent installation of an alkene group. By strategic use of these two reactions and through late-stage diversifications of the functionalized schizozygane core, the first and asymmetric total syntheses of (+)-schizozygine, (+)-3-oxo-14α,15α-epoxyschizozygine, and (+)-α-schizozygol and the total synthesis of (+)-strempeliopine have been accomplished in 11-12 steps from tryptamines.
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We report here a concise, collective, and asymmetric total synthesis of sarpagine alkaloids and biogenetically related koumine alkaloids, which structurally feature a rigid cage scaffold, with L-tryptophan as the starting material. Two key bridged skeleton-forming reactions, namely tandem sequential oxidative cyclopropanol ring-opening cyclization and ketone α-allenylation, ensure concurrent assembly of the caged sarpagine scaffold and installation of requisite derivative handles. With a common caged intermediate as the branch point, by taking advantage of ketone and allene groups therein, total synthesis of five sarpagine alkaloids (affinisine, normacusineâ B, trinervine, Na -methyl-16-epipericyclivine, and vellosimine) with various substituents and three koumine alkaloids (koumine, koumimine, and N-demethylkoumine) with more complex cage scaffolds has been accomplished.
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Alcaloides Indólicos/síntesis química , Alcaloides Indólicos/química , Conformación Molecular , EstereoisomerismoRESUMEN
OBJECTIVE: To establish a new detection method for cytomegalovirus (CMV) specific cytotoxic CD8(+)T cells and examine its proportion and significance in peripheral blood from kidney transplant recipients. METHODS: A total of 30 recipients of kidney transplantation from January 2009 to December 2010 for the first time were enrolled. And 10 healthy volunteers were selected as health control group. Tetramer technology was applied. The proportions of CMV antigen specific T cells expressed in each group were detected directly by flow cytometry. RESULTS: The positive rate of CMV antigen specific CTL, CMV-pp65 specific CD8(+)T cell was between 0.16%-7.21% in kidney transplant recipients (n = 30) and health control group (n = 10). The proportions of CMV antigen specific CTL were 2.95% ± 0.62% in CMV+ group. And it was significantly higher than that in CMV-group (1.17% ± 0.45%) and health control group (0.65% ± 0.17%) (P = 0.003,0.006). In CMV+ group, the proportion of CMV antigen specific CTL was 2.95% ± 0.62% in CMV-pp65 positive phase and decreased significantly to 1.50% ± 0.32% after turning into negative phase. In CMV+ group (n = 15), the proportion of CMV antigen specific CTL was positively related with the number of CMV-pp65 positive cells (Pearson test, r = 0.871, P < 0.01). CONCLUSIONS: The proportion of specific CTL is an important guide for evaluating and judging the prognosis of CMV infection. And it may provide rationales for future targeted therapy in kidney transplant recipients.
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Citomegalovirus , Trasplante de Riñón , Linfocitos T , Antígenos Virales , Infecciones por Citomegalovirus , Citometría de Flujo , Humanos , RiñónRESUMEN
OBJECTIVE: To evaluate the clinical values of T-lymphocyte cytokines in renal transplant acute rejection. METHODS: A total of 31 recipients with renal transplantation and 15 healthy volunteers from January 2010 to January 2012 were enrolled and divided into acute rejection group (n = 11) and stable renal allograft function group (n = 20) according to the inclusion criteria. Peripheral blood was collected from the patients before transplantation, 1, 7, 14, 28 day after transplantation and acute rejection onset. Cytometric bead array (CBA) was used to monitor the levels of interleukin-17 (IL-17), interferon-gamma (IFN-γ), tumor necrosis factor (TNF), interleukin(IL)-10, IL-6, IL-4 and IL-2. The associations of the changes and levels of cytokines in 3 groups were examined with Pearson correlation analysis. RESULTS: The levels of IL-17A, TNF, IL-10 and IL-2 in recipients before transplantation were (3.40 ± 1.29) , (1.79 ± 0.53) , (2.73 ± 0.65) and (1.79 ± 1.02) ng/L respectively and decreased significantly compared to healthy volunteers ((4.52 ± 2.01), (3.36 ± 1.09) , (3.91 ± 0.42) , (3.12 ± 1.07) ng/L respectively, all P < 0.05). However the levels of IFN-γ, IL-6 and IL-4 showed no significant changes between two groups (all P > 0.05). In acute rejection group after transplantation, the levels of IL-17A, IFN-γ, IL-10 and IL-6 were (9.47 ± 4.75) , (5.01 ± 2.23) , (12.20 ± 5.79) , (6.55 ± 3.45) ng/L respectively and increased significantly compared to the renal allograft function group ((4.39 ± 1.26), (2.90 ± 0.87),(5.68 ± 2.25) and (2.10 ± 0.70) ng/L respectively, all P < 0.05); the level of IL-17A was correlated with those of IFN-γ and IL-4 (Pearson r = 0.519, 0.395, both P < 0.01), the level of IFN-γ was correlated with those of IL-4 and IL-2 (r = 0.276, 0.335, all P < 0.05) , the level of TNF was correlated with that of IL-4 (r = 0.423, P < 0.05) and the level of IL-10 was correlated with that of IL-6 (r = 0.361, P < 0.05). CONCLUSIONS: Cytokines play an important role in acute rejection of renal transplant. And further understanding of its mechanism may provide experimental and preventive rationales.
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Trasplante de Riñón , Linfocitos T , Citocinas , Humanos , Receptores de Trasplantes , Trasplante HomólogoRESUMEN
Soil thallium (Tl) pollution is a serious environmental problem, and vegetables are the primary pathway for human exposure to Tl. Therefore, it is important to investigate the characteristics of soil Tl uptake by vegetables. In this study, the meta-analysis approach was first applied to explore the relationship between Tl content in vegetables and soil environment, as well as key factors influencing soil physical-chemical properties, and to derive soil thresholds for Tl. The results indicated that various types of vegetables have different capabilities for Tl accumulation. Vegetables from contaminated areas showed high Tl accumulation, and the geomean Tl content in different types of vegetables was in the following order: leafy > root-stalk > solanaceous vegetables. Taro and kale had significantly higher capability to accumulate soil Tl among the 35 species studied, with Tl bioconcentration factor values of 0.060 and 0.133, respectively. Pearson correlation analysis and meta-analysis revealed that the Tl content in vegetables was significantly correlated with soil pH and Tl content in soil. The linear predictive model for Tl accumulation in vegetables based on soil Tl content described the data well, and the fitting coefficient R2 increased with soil pH value. According to potential dietary toxicity, the derived soil Tl thresholds for all, leafy and root-stalk vegetables increased with an increase in soil pH, and were in the range of 1.46-6.72, 1.74-5.26 and 0.92-6.06 mg/kg, respectively. The soil Tl thresholds for kale, lettuce and carrot were in the range of 0.24-4.89, 2.94-3.32 and 3.77-14.43 mg/kg, respectively. Ingestion of kale, beet, sweet potato, potato, taro, pepper, turnip, Chinese cabbage, eggplant and carrot poses potential health risks. The study provides scientific guidance for vegetable production in Tl-contaminated areas and can help with the selection of vegetable species suitable for avoiding the absorption of Tl from contaminated soil.
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Brassica , Contaminantes del Suelo , Humanos , Verduras/química , Talio/análisis , Suelo/química , Contaminantes del Suelo/análisis , Brassica/química , ChinaRESUMEN
Flat-band systems with strongly correlated electrons can exhibit a variety of phenomena, such as correlated insulating and topological states, unconventional superconductivity, and ferromagnetism. Rhombohedral multilayer graphene has recently emerged as a promising platform for investigating exotic quantum states due to its hosting of topologically protected surface flat bands at low energy, which have a layer-dependent energy dispersion. However, the complex relationship between the surface flat bands and the highly dispersive high-energy bands makes it difficult to study correlated surface states. In this study, we introduce moiré superlattices as a method to isolate the surface flat bands of rhombohedral multilayer graphene. The observed pronounced screening effects in the moiré potential-modulated rhombohedral multilayer graphene indicate that the two surface states are electronically decoupled. The flat bands that are isolated promote correlated surface states in areas that are distant from the charge neutrality points. Notably, we observe tunable layer-polarized ferromagnetism, which is evidenced by a hysteretic anomalous Hall effect. This is achieved by polarizing the surface states with finite displacement fields.
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PURPOSE: The outcome of renal transplantation is difficult to predict, even with an allograft biopsy. The aim of this study was to develop a sensitive, specific and noninvasive method for prediction of acute cellular rejection (ACR). METHODS: Luminex analysis was used to determine the levels of 95 cytokines/chemokines and their soluble receptors in sera from recipients with: ACR (in the first month post-transplantation, before and during rejection, and after rejection reversal); stable allograft function; delayed graft function (DGF); pulmonary infection. Evaluation of significant differential protein expression in ACR patients compared with stable allograft controls revealed a three-analyte combination as a marker of renal transplantation outcome. The predictive value of this combination was further validated in DGF and infection groups and in a blind binary code study of 24 additional serum samples. RESULTS: Significant differential expression was detected in 26 proteins expressed in patients during the period preceding an ACR episode compared with stable controls. A blood test for discrimination of such patients was developed based on the simultaneous quantification of three analytes (IL-1 receptor antagonist, IL-20 and sCD40 ligand). This test exhibited 90.9 % sensitivity, 96 % specificity, a positive predictive value (PPV) of 95.2 % and a negative predictive value (NPV) of 92.3 %. Moreover, this combination allowed discrimination between patients with ACR and DGF and pulmonary infection. CONCLUSIONS: With further development and validation, this blood test can be used to predict ACR and direct the treatment of transplant patients in the clinic.
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Ligando de CD40/sangre , Rechazo de Injerto/inmunología , Proteína Antagonista del Receptor de Interleucina 1/sangre , Interleucinas/sangre , Trasplante de Riñón/inmunología , Enfermedad Aguda , Adulto , Femenino , Rechazo de Injerto/sangre , Rechazo de Injerto/patología , Humanos , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/patología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios RetrospectivosRESUMEN
RATIONALE: Due to the widespread use of broad-spectrum antibiotics, the morbidity of prostate abscesses (PA) has declined dramatically. However, under special circumstances, such as invasive procedures and immunosuppressive conditions, some patients are more likely to develop this disease. Here, we present the case of a 21-year-old man, diagnosed with PA, with a history of chronic steroid use and a long-term indwelling urinary catheter. The pathogen was confirmed as carbapenem-resistant Klebsiella pneumoniae, a rare bacterium. This case indicates that immunodeficiency and invasive catheter use may be risk factors for PA and opportunistic bacterial infections. PATIENT CONCERNS: A 21-year-old young man presented with sudden onset of high fever (39.7°C). The patient had a history of long-term use of steroids and long-term indwelling urinary catheter. Digital rectal examination revealed obvious swelling and tenderness of the prostate. Subsequent pelvic magnetic resonance imaging showed a high signal lesion measuring 2.1â ×â 2.9â ×â 2.8 cm with T1 enhancement and T2 enhancement. DIAGNOSES: On the 8th day of hospitalization, the patient underwent a PA drainage procedure and a pus culture was conducted. Subsequent pus and urine cultures showed the presence of Klebsiella pneumoniae, which exhibited resistance to all injectable carbapenems, cephalosporins, aminoglycosides, piperacillin-tazobactam, and quinolone drugs. INTERVENTIONS: On the 8th day of hospitalization, the patient underwent PA drainage surgery under general anesthesia to drain the abscess and relieve obstruction. After the surgery, the patient received a 2-week treatment of doxycycline. OUTCOMES: Finally, the patient was discharged after recovery and did not experience recurrence during the 6-month follow-up period. LESSONS: PA is not commonly found, but some patients are more susceptible to this disease under certain host conditions. Immunodeficiency and invasive catheter use may be risk factors for PA and opportunistic bacterial infections. The use of omadacycline for the treatment of carbapenem-resistant Klebsiella pneumoniae infections appears to be effective.
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Infecciones por Klebsiella , Neumonía , Enfermedades de la Próstata , Humanos , Masculino , Adulto Joven , Absceso/tratamiento farmacológico , Antibacterianos/farmacología , Carbapenémicos/farmacología , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae , Neumonía/tratamiento farmacológicoRESUMEN
Nuclear factor-κB (NF-κB)-mediated inflammation is a major cause of acute respiratory distress syndrome (ARDS). However, the regulatory mechanisms by which NF-κB transactivates proinflammatory cytokines remain unclear in the pathogenesis of ARDS. Herein, we report that the activating protein 1 (AP1) transcription factor recruits a histone acetyltransferase p300 and a transcriptional regulator C-terminal binding protein 1 (CtBP1) to assemble the CtBP1-p300-AP1 complex, which transactivates the expression of hsa-miR-7-5p in ARDS biopsies. Overexpressed hsa-miR-7-5p binds to the three prime untranslated regions (3'-UTRs) of ataxin 1 (ATXN1), suppressing its expression. Decreased ATXN1 expression relieves its repression of NF-κB, causing the induction of proinflammatory cytokine genes and triggering an inflammatory response. Depletion of CtBP1 or treatments with two CtBP1 inhibitors (NSC95397 and 4-methylthio-2-oxobutanoate (MTOB)) in human macrophages impairs the assembly of the CtBP2-p300-AP1 complex, resulting in decreased hsa-miR-7-5p levels, upregulation of ATXN1, and attenuation of proinflammatory cytokines. A similar regulatory mechanism was observed in lipopolysaccharide-treated mice. Our results reveal that increased hsa-miR-7-5p level mediated by the CtBP1-p300-AP1 complex targets ATXN1 to trigger an NF-κB-dependent inflammatory response. Interfering with this signaling pathway to block the inflammatory response may be a strategy for treating ARDS. KEY MESSAGES : The transcription factor AP1 recruits p300 and CtBP1 to form a transcriptional complex, which transactivates the expression of hsa-miR-7-5p in ARDS biopsies. Overexpressed hsa-miR-7-5p binds to the 3'-UTR of ATXN1, suppressing its expression. The decreased ATXN1 impaired its suppression of NF-κB, causing the induction of proinflammatory cytokine genes and triggering inflammation response. Disruption of the assembly of CtBP2-p300-AP1 complex upregulates ATXN1 and attenuates inflammation.
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MicroARNs , FN-kappa B , Animales , Humanos , Ratones , Oxidorreductasas de Alcohol/genética , Ataxina-1 , Proteínas Co-Represoras/genética , Citocinas , Inflamación/genética , Inflamación/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , FN-kappa B/metabolismo , Factores de Transcripción , Factor de Transcripción AP-1RESUMEN
OBJECTIVE: To demonstrate the therapeutic effect of vasopressin as an alternative treatment for cardiac arrest. DESIGN: Systematic review and meta-analysis. METHODS: PubMed, EMBASE, the Cochrane Library and Web of Science were searched for randomised controlled trials. The intervention included administration of vasopressin alone or vasopressin combined with epinephrine or vasopressin, steroids and epinephrine (VSE) versus epinephrine combined with placebo as control group. The primary outcome was the return of spontaneous circulation (ROSC). The secondary outcomes included mid-term survival and mid-term good neurological outcome. We conducted subgroup analyses of the primary outcome based on different settings, different study drug strategies and different types of initial rhythm. RESULTS: Twelve studies (n=6718) were included, of which eight trials (n=5638) reported the data on patients with out-of-hospital cardiac arrest and four trials (n=1080) on patients with in-hospital cardiac arrest (IHCA). There were no significant differences between intravenous vasopressin and placebo in the outcomes of ROSC (relative risk (RR): 1.11; 95% CI: 0.99 to 1.26), mid-term survival (RR: 1.23; 95% CI: 0.90 to 1.66) and mid-term good neurological outcome (RR: 1.20; 95% CI: 0.77 to 1.87). However, in the subgroup analysis, intravenous vasopressin as part of VSE can significantly improve the rate of ROSC (RR: 1.32; 95% CI: 1.18 to 1.47) but not the rate of mid-term survival (RR: 2.15; 95% CI: 0.75 to 6.16) and mid-term good neurological outcome (RR: 1.80; 95% CI: 0.81 to 4.01) for patients with IHCA. CONCLUSIONS: Our study failed to demonstrate increased benefit from vasopressin with or without epinephrine compared with the standard of care. However, vasopressin as a part of VSE is associated with the improvement of ROSC in patients with IHCA, and the benefit on mid-term survival or mid-term good neurological outcome is uncertain. Larger trials should be conducted in the future to address the effect of vasopressin only, vasopressin plus epinephrine or VSE on cardiac arrest. PROSPERO REGISTRATION NUMBER: CRD42021293347.
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Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Humanos , Vasoconstrictores/uso terapéutico , Epinefrina/uso terapéutico , Vasopresinas/uso terapéutico , Paro Cardíaco Extrahospitalario/terapiaRESUMEN
We present a camera-based human body parameters measurement approach and develop a human postural assessment system. The approach combines the conventional contact measurement method and the non-contact measurement method to overcome some shortcomings in terms of time, expense, and professionalism in early methods. The entire measurement system consists of a computer, a high-definition camera, and the sticky points that are applied to the participant's body before the measurement. The camera captures the triple view image of human body. Then, the human body outline and the joint points of the human skeleton are extracted to locate the bone feature points. Finally, measurements and extractions of the human parameters are made. Experimental results demonstrate that the global postural assessment system provides quantitative guidance for human postural evaluation, and it completely changes how human postural is evaluated. The postural assessment system is significant for early diagnosis of diseases and medical rehabilitation treatment.
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Diagnóstico por Imagen , Cuerpo Humano , Postura , HumanosRESUMEN
High-frequency land-use changes caused by rapid economic development have become a key factor in the imbalance of carbon sequestration within regions. How to balance economic development and ecological protection is a difficult issue for regional planning. Studying the relationship between future land-use changes and ecosystem carbon storage (CS) is of important significance for the optimization of regional land-use patterns. The research used the gray prediction model and coupled the patch-generating land-use simulation (PLUS) model and the integrated valuation of ecosystem services and trade-offs (InVEST) model. On this basis, the evolution characteristics and spatial coordination between land-use changes and CS in the Dongting Lake Basin (DLB) in different scenarios in 2030 were simulated. The results show that: (1) The spatial distribution of CS remains stable in different scenarios, while land-use types with high carbon density in the periphery of cities are constantly invaded by construction land, which results in the greatest carbon loss in the urban areas. (2) Compared with the natural evolution scenario (NES), only 195.19 km2 of land-use types with high carbon density are transformed into construction land in the ecological protection scenario (EPS), generating a carbon sink gain of 182.47 × 104 Mg. Conversely, in the economic development scenario (EDS), a total of over 1400 km2 of farmland and ecological land are transformed into construction land, which weakens the carbon sequestration capacity of ecosystems, and more than 147 × 104 Mg of carbon loss occurs in the urban areas. (3) The planned development scenario (PDS) takes ecological protection and economic development both into consideration, which not only generates a carbon sink gain of 121.33 × 104 Mg but also reduces the carbon loss in urban areas by more than 50%. The PDS performs well in both land use and CS growth and can better motivate the effect of land-use changes in increasing the carbon sink, which is also proved by analysis of the coordination between land-use intensity (LUI) and CS. Therefore, the PDS better satisfies the future development demand of DLB and can provide a reference for sustainable land use in the basin.
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Ecosistema , Lagos , Carbono , Conservación de los Recursos Naturales , ChinaRESUMEN
Bridged frameworks are of high chemical and biological significance, being ubiquitous in pharmaceutical molecules and natural products. Specific structures are usually preformed to build these rigid segments at the middle or late stage in the synthesis of polycyclic molecules, resulting in decreased synthetic efficiency and target-specific syntheses. As a logically distinct synthetic strategy, we constructed an allene/ketone-equipped morphan core at the outset through an enantioselective α-allenylation of ketones. Experimental and theoretical results revealed that the high reactivity and enantioselectivity of this reaction are attributed to the cooperative effects of the organocatalyst and metal catalyst. The bridged backbone generated was employed as a structural platform to guide and facilitate the assembly of up to five fusing rings, and the allene and ketone groups thereon were used to precisely install various functionalities at C16 and C20 at the late stage, leading to a concise, collective total synthesis of nine strychnan alkaloids.
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Introduction: Mutations in KIT proto-oncogene, receptor tyrosine kinase (KIT) and platelet-derived growth factor receptor-α (PDGFRA) render the available tyrosine kinase inhibitors (TKI) ineffective in treating advanced gastrointestinal stromal tumors (GIST). Ripretinib, a broad-spectrum switch-control kinase inhibitor, has shown increased efficacy and manageable safety, but real-world evidence remains scarce. This study evaluates the efficacy and safety of ripretinib among Chinese patients in a real-world setting. Methods: Advanced GIST patients (N=23) receiving ripretinib following progression on previous lines of TKI treatment were enrolled to determine the efficacy [progression-free survival (PFS) and overall survival (OS)]. Safety was assessed by the incidence and severity of adverse events (AEs). All statistical analyses were performed using SPSS version 20.0 and a p-value of <0.05 was considered significant. Results: The median PFS (mPFS) of efficacy analysis set (EAS) (N=21) was 7.1 months. mPFS of patients receiving ripretinib following ≤2 lines of previous TKI treatment and ≥3 prior lines of therapy were 7.1 and 9.2 months, respectively. The median OS (mOS) was 12.0 months and shorter interval between the end of the latest TKI and ripretinib therapy was correlated with longer median PFS and OS (p=0.054 and p=0.046), respectively. Alopecia and asthenia were the most common AEs observed. Conclusion: Compared to previous lines of TKI in advanced GIST patients, ripretinib showed superior efficacy with clinically manageable AEs. Real-world results are comparable to that of phase III INVICTUS study and its Chinese bridging study. Hence, ripretinib can be used for the clinical management of advanced GIST patients.
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BACKGROUND: Up to 80% of patients in the intensive care unit (ICU) suffer from delirium. Studies on the preventative use of melatonin in the ICU have produced mixed results. We performed a systematic review and meta-analysis to evaluate whether early administration of melatonin reduces the prevalence of delirium in critically ill patients. METHODS: We searched Medline, Embase, and the Cochrane Library for randomized controlled trials comparing melatonin or melatonin agonists to placebo in ICU setting. The population included adult patients in the ICU. The primary outcome was the prevalence of delirium. Secondary outcomes included duration of delirium, delirium-free day, serum melatonin concentration, need for sedation, duration of mechanical ventilation, hospital and ICU length of stay (LOS), all-cause mortality, sleep quality, and adverse events. Trial sequential analysis (TSA) was performed on the primary outcome to prevent the risk of random error and multiplicity phenomenon as a result of repeated significance testing across all the included trials. RESULTS: Twelve trials with a total of 2538 patients were analyzed. When all trials were pooled, the incidence of delirium in ICU patients who received melatonin was significantly lower than in those who received placebo (risk ratio, 0.77; 95% confidence interval: 0.61-0.96; I2â =â 56%). There were no significant differences in secondary outcomes including duration of delirium, duration of mechanical ventilation, ICU LOS, hospital LOS, and mortality. TSA indicated that Z-curve crossed the traditional boundary, but did not cross the monitoring boundary for benefit, which indicated that it is still inconclusive that melatonin affects the incidence of delirium. CONCLUSIONS: This meta-analysis found that early administration of melatonin may result in a decreased delirium prevalence in critically ill patients. However, the sensitivity analysis of high-quality studies did not support this finding. In addition, TSA demonstrated that the result may have false-positive error. Therefore, this finding should be interpreted with caution. Further studies are needed to examine the effectiveness of prophylactic melatonin on the prevalence and duration of ICU delirium in the future.
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Enfermedad Crítica , Melatonina , Adulto , Humanos , Cuidados Críticos , Unidades de Cuidados Intensivos , Tiempo de Internación , Melatonina/uso terapéuticoRESUMEN
Arsenic pollution in freshwater poses a serious threat to aquatic organisms. However, dissolved organic matter (DOM) in water can modulate arsenic environmental toxicity by either suppressing or promoting its bioaccumulation. In this study, we investigated the toxicity, bioaccumulation, and biotransformation of inorganic arsenic (arsenite AsIII and arsenate AsV) combined with two types of DOM, i.e., humic acid (HA) and fulvic acid (FA), in the algae Chlamydomonas reinhardtii and Ochromonas danica. C. reinhardtii has a cell wall and cannot bioaccumulate arsenic complexation, whereas O. danica has no cell wall. Without DOM, AsV was more toxic than AsIII for C. reinhardtii, and AsV was less toxic than AsIII for O. danica. HA and FA addition reduced AsV and AsIII toxicities; the larger molecular weight (Mw) of HA contributed to the reduction in toxicity to an even greater extent, and reduced arsenic accumulation while promoting the biotransformation ability of C. reinhardtii, which has a cell wall. However, HA and FA addition increased AsV and AsIII toxicities and arsenic accumulation while relatively enhancing the biotransformation ability of O. danica, which has no cell wall. Coupling toxicity, bioaccumulation, and biotransformation, DOM (HA and FA) contributed to the altered toxicity of freshwater algae to AsV and AsIII through reduced/increased arsenic accumulation and enhanced biotransformation. Overall, our study considered the combined toxicity of inorganic arsenic and DOM in phytoplankton, helping estimate the potential environmental risk of arsenic in aqueous environments.
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Arsénico , Arsenicales , Arsenitos , Contaminantes Químicos del Agua , Arseniatos/metabolismo , Arseniatos/toxicidad , Arsénico/toxicidad , Arsenitos/metabolismo , Arsenitos/toxicidad , Biotransformación , Agua Dulce , Sustancias Húmicas , Contaminantes Químicos del Agua/toxicidadRESUMEN
BACKGROUND: Intravenous fluids are used commonly for almost all intensive care unit (ICU) patients, especially for patients in need of resuscitation. The selection and use of resuscitation fluids may affect the outcomes of patients; however, the optimal resuscitative fluid remains controversial. METHODS: We systematically searched PubMed, Embase, and CENTRAL. Studies comparing balanced crystalloids and normal saline in ICU patients were selected. We used the Cochrane Collaboration tool to assess the risk of bias in studies. The primary outcome was mortality at the longest follow-up. Secondary outcomes included the incidence of acute kidney injury (AKI) and new renal replacement therapy (RRT). RESULTS: A total of 35,456 patients from eight studies were included. There was no significant difference between balanced crystalloid solutions and saline in mortality (risk ratio [RR]: 0.96; 95% confidence interval [CI]:0.92-1.01). The subgroup analysis with traumatic brain injury (TBI) showed lower mortality in patients receiving normal saline (RR:1.25; 95% CI 1.02-1.54). However, in patients with non-TBI, balanced crystalloid solutions achieved lower mortality than normal saline (RR: 0.94; 95% CI 0.90-0.99). There was no significant difference in moderate to severe AKI (RR: 0.96; 95% CI 0.90-1.01) or new RRT (RR: 0.94; 95% CI 0.84-1.04). CONCLUSIONS: Compared with normal saline, balanced crystalloids may not improve the outcomes of mortality, the incidence of AKI, and the use of RRT for critically ill patients. However, balanced crystalloids reduce the risk of death in patients with non-TBI but increase the risk of death in those with TBI. Large-scale rigorous randomized trials with better designs are needed, especially for specific patient populations.
Asunto(s)
Lesión Renal Aguda , Solución Salina , Lesión Renal Aguda/etiología , Lesión Renal Aguda/terapia , Enfermedad Crítica/terapia , Soluciones Cristaloides , Femenino , Fluidoterapia , Humanos , Soluciones Isotónicas/uso terapéutico , Masculino , Solución Salina/uso terapéuticoRESUMEN
OBJECTIVES: Linezolid can significantly impact drug-resistant tuberculosis (DR-TB) patient outcomes. However, the long-term use of this drug for TB treatment has been limited by adverse reactions and uncertainty regarding optimal dosage regimens for balancing drug efficacy and safety across different populations. This study attempted to find the optimal dosing regimen of linezolid in different populations. METHODS: A total of 355 blood samples were collected from 126 DR-TB patients. Population pharmacokinetic analysis (using a one-compartment model) and dose simulations were conducted using NONMEM and R software. The ratio between the area under the free drug plasma concentration-time curve to the MIC (fAUC/MIC) of > 119 and trough concentration (Cmin) ≤ 2 mg/L served as efficacy and safety targets, respectively, toward the formulation of optimal dosage regimens based on a ≥ 90% cumulative fraction of response. RESULTS: Body weight and blood urea nitrogen levels were the most significant covariates of apparent volume, while creatinine clearance and haemoglobin level significantly influenced apparent clearance. The probability of target attainment for different dosage regimens was evaluated via Monte Carlo simulation. For subjects with MICs of 0.125, 0.25 and 0.5 mg/L, specific total daily doses of ≥ 300 mg, ≥ 450 mg and ≥ 900 mg were required to reach the target, respectively. Subjects with body weight ≤ 70 kg and MIC ≥ 1 mg/L received a total 1200 mg daily dose to reach the probability of target attainment target. Notably, single dosing was safer than multiple dosing at the same daily dose. The optimal dosage regimens for subjects with body weight < 50 kg and ≥ 50 kg were 450 mg/d and 600 mg/d (once daily), respectively. CONCLUSION: Optimal dosage regimens for patients weighing < 50 kg and ≥ 50 kg were 450 mg/d and 600 mg/d, respectively. A single dose was safer than multiple doses.