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Dysregulation of microRNA (miRNA) expression in cancer is a significant factor contributing to the progression of chemoresistance. The objective of this study is to explore the underlying mechanisms by which miR-34b-3p regulates chemoresistance in cervical cancer (CC). Previous findings have demonstrated low expression levels of miR-34b-3p in both CC chemoresistant cells and tissues. In this study, we initially characterize the behavior of SiHa/DDP cells which are CC cells resistant to the chemotherapeutic drug cisplatin (DDP). Subsequently, miR-34b-3p mimics are transfected into SiHa/DDP cells. It is observed that overexpression of miR-34b-3p substantially inhibits the proliferation, migration, and invasion abilities of SiHa/DDP cells and also enhances their sensitivity to DDP-induced cell death. Quantitative RT-PCR and western blot analysis further reveal elevated expression levels of STC2 and FN1 in SiHa/DDP cells, contrary to the expression pattern of miR-34b-3p. Moreover, STC2 and FN1 contribute to DDP resistance, proliferation, migration, invasion, and decreased apoptosis in CC cells. Through dual-luciferase assay analysis, we confirm that STC2 and FN1 are direct targets of miR-34b-3p in CC. Finally, rescue experiments demonstrate that overexpression of either STC2 or FN1 can partially reverse the inhibitory effects of miR-34b-3p overexpression on chemoresistance, proliferation, migration and invasion in CC cells. In conclusion, our findings support the role of miR-34b-3p as a tumor suppressor in CC. This study indicates that targeting the miR-34b-3p/STC2 or FN1 axis has potential therapeutic implications for overcoming chemoresistance in CC patients.
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Proliferação de Células , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Fibronectinas , MicroRNAs , Neoplasias do Colo do Útero , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/tratamento farmacológico , Feminino , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Fibronectinas/metabolismo , Fibronectinas/genética , Movimento Celular/genética , Movimento Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Apoptose/genética , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , GlicoproteínasRESUMO
Neural tube defects (NTDs) represent a developmental disorder of the nervous system that can lead to significant disability in children and impose substantial social burdens. Valproic acid (VPA), a widely prescribed first-line antiepileptic drug for epilepsy and various neurological conditions, has been associated with a 4-fold increase in the risk of NTDs when used during pregnancy. Consequently, urgent efforts are required to identify innovative prevention and treatment approaches for VPA-induced NTDs. Studies have demonstrated that the disruption in the delicate balance between cell proliferation and apoptosis is a crucial factor contributing to NTDs induced by VPA. Encouragingly, our current data reveal that melatonin (MT) significantly inhibits apoptosis while promoting the restoration of neuroepithelial cell proliferation impaired by VPA. Moreover, further investigations demonstrate that MT substantially reduces the incidence of neural tube malformations resulted from VPA exposure, primarily by suppressing apoptosis through the modulation of intracellular reactive oxygen species levels. In addition, the Src/PI3K/ERK signaling pathway appears to play a pivotal role in VPA-induced NTDs, with significant inhibition observed in the affected samples. Notably, MT treatment successfully reinstates Src/PI3K/ERK signaling, thereby offering a potential underlying mechanism for the protective effects of MT against VPA-induced NTDs. In summary, our current study substantiates the considerable protective potential of MT in mitigating VPA-triggered NTDs, thereby offering valuable strategies for the clinical management of VPA-related birth defects.
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Melatonina , Defeitos do Tubo Neural , Gravidez , Feminino , Criança , Humanos , Ácido Valproico , Melatonina/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/prevenção & controle , Estresse Oxidativo , Transdução de SinaisRESUMO
In the field of industrial semi-hydrogenation of trace alkynes amidst alkene feedstocks, the pivotal challenge lies in circumventing the hydrogenation of alkenes. Herein, we present Zr(OH)4 as an innovative catalyst for the semi-hydrogenation of phenylacetylene, demonstrating remarkable selectivity towards styrene (>96%), while exhibiting inactivity towards free styrene. Notably, Zr(OH)4 achieves a 95% conversion of quasi-industry 1 mol% phenylacetylene within styrene, with a mere 0.44% styrene loss. Experimental and theoretical results confirm both terminal Zr-O-H and bridge Zr-O-H can dissociate H2, while the terminal Zr-O-H plays a crucial role on activating phenylacetylene through the sequential hydrogenation process of C6H5C≡CHâC6H5C=CH2âC6H5CH=CH2. The high rate of phenylacetylene removal is attributed to its strong adsorption capacity, while Zr(OH)4 has a significantly weaker adsorption capacity for styrene.
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INTRODUCTION: Retrograde cerebral perfusion (RCP) is a safe and effective technique to augment cerebral protection during lower body circulatory arrest in patients undergoing elective hemiarch replacement. However, recommendations guiding optimal temperature, flow rate, and perfusion pressure are outdated and potentially overly limiting. We report our experience using RCP for elective hemiarch replacement with parameters that challenge the currently accepted paradigm. METHODS: This was a single-center, retrospective analysis of 319 adult patients who underwent elective hemiarch replacement between February 2010 and 2021 using hypothermic lower body circulatory arrest with RCP alone, RCP followed by antegrade cerebral perfusion (ACP), or ACP alone. Flow rates were adjusted to maintain cerebral perfusion pressure between 30 and 50 mm Hg for RCP and between 40 and 60 mm Hg for ACP. RESULTS: RCP was used in 22.6% (n = 72) of cases, whereas ACP alone was performed in 77.4% (n = 247) of cases. Baseline patient characteristics were similar between groups. Patients undergoing RCP demonstrated shorter cross-clamp time (97.0 min versus 100.0 min, P = 0.034) and shorter lower body circulatory arrest time (7.0 min versus 10.0 min, P < 0.0001) compared with ACP alone. Nadir bladder temperature was equivalent between groups (27.3°C versus 27.5°C, P = 0.752). There were no significant differences in postoperative complications, neurologic outcomes, or mortality. CONCLUSIONS: Moderate hypothermic lower body circulatory arrest combined with RCP at target perfusion pressures of 30-50 mm Hg in patients undergoing elective hemiarch replacement results in equivalent neurologic outcomes and overall morbidity to cases using ACP alone. These results challenge the currently accepted paradigm for RCP, which typically uses deep hypothermia while keeping perfusion pressures below 25 mm Hg.
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Parada Cardíaca , Hipotermia Induzida , Adulto , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Parada Circulatória Induzida por Hipotermia Profunda , Perfusão/métodos , Circulação Cerebrovascular , Aorta Torácica/cirurgia , Hipotermia Induzida/métodosRESUMO
BACKGROUND: A potentially curative hepatic resection is the optimal treatment for hepatocellular carcinoma (HCC), but most HCCs, even at an early stage, eventually recur after resection. This study investigates clinical features of initial recurrence and long-term prognosis of patients with recurrence after curative resection for early-stage HCC. PATIENTS AND METHODS: From a multicenter database, patients who underwent curative hepatic resection for early-stage HCC [Barcelona Clinic Liver Cancer (BCLC) stage 0/A] were extracted. Time to initial recurrence, patterns of initial recurrence, and treatment modalities for recurrent tumors were investigated. Univariate and multivariate analysis were used to identify independent risks associated with postoperative recurrence, as well as post-recurrence survival (PRS) for patients with recurrence. RESULTS: Among 1424 patients, 679 (47.7%) developed recurrence at a median follow-up of 54.8 months, including 408 (60.1%) early recurrence (≤ 2 years after surgery) and 271 (39.9%) late recurrence (> 2 years). Independent risks of postoperative recurrence included cirrhosis, preoperative alpha-fetoprotein level > 400 ug/L, tumor size > 5 cm, multiple tumors, satellites, microvascular invasion, and intraoperative blood transfusion. Multivariate analysis revealed that receiving irregular recurrence surveillance, initial tumor beyond Milan criteria, early recurrence, BCLC stage B/C of the recurrent tumor, and noncurative treatments were independently associated with poorer PRS. CONCLUSIONS: Nearly half of patients with early-stage HCC experienced recurrence after resection. Understanding recurrence risks may help identify patients at high risk of recurrence who may benefit from future adjuvant therapies. Meaningful survival even after recurrence can still be achieved by postoperative regular surveillance and curative treatment.
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BACKGROUND: Assessment of quality in the perioperative period is critical to ensure good patient care. Textbook outcomes (TO) have been proposed to combine several parameters into a single defined quality metric. The association of preoperative body mass index (BMI) with incidences of achieving or not achieving TO (non-TO) among patients undergoing hepatectomy for hepatocellular carcinoma (HCC) was characterized. METHODS: Patients who underwent curative-intent hepatectomy for HCC between 2015 and 2018 were identified from a multicenter database. These patients were divided into three groups based on preoperative BMI: low-BMI (≤ 18.4 kg/m2), normal-BMI (18.5-24.9 kg/m2), and high-BMI (≥ 25.0 kg/m2). The incidences of non-TO among these three groups were compared. Multivariate analyses were performed to identify whether there was any independent association between preoperative BMI and non-TO. RESULTS: Among 1206 patients, 100 (8.3%), 660 (54.7%), and 446 (37.0%) were in the low-BMI, normal-BMI, and high-BMI groups, respectively. The incidence of non-TO was 65.6% in the whole cohort. The incidence of non-TO was significantly higher among patients in the low- and high-BMI cohorts versus the normal-BMI cohort (75.0% and 74.7% versus 58.0%, both P < 0.01). After adjustment of other confounding factors on multivariate analysis, low-BMI and high-BMI were independently associated with higher incidences of non-TO compared with normal-BMI (OR: 1.98 and 2.27, both P < 0.05). CONCLUSIONS: Two out of three patients did not achieve TO after hepatectomy for HCC. Both preoperative low-BMI and high-BMI were independently associated with lower odds to achieve optimal TO following HCC resection.
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Surgical site infections (SSI) following congenital heart surgery (CHS) remain a significant source of morbidity. Delayed sternal closure (DSC) is often required to minimize the potential for hemodynamic instability. The purpose of this study was to determine the incidence of SSI among patients undergoing DSC versus primary chest closure (PCC) and to define a potential inflection point for increased risk of SSI as a function of open chest duration (OCD).A retrospective review of our institutional Society of Thoracic Surgeons dataset is to identify patients undergoing CHS at our institution between 2015 and 2020. Incidences of SSI were compared between DSC and PCC patients. DSC patients were evaluated to determine the association of OCD and the incidence of SSI.2582 operations were performed at our institution between 2015 and 2020, including 195 DSC and 2387 PCC cases. The incidence of SSI within the cohort was 1.8% (47/2,582). DSC patients had significantly higher incidences of SSI (17/195, 8.7%) than PCC patients (30/2387, 1.3%, p < 0.001). Further, patients with an OCD of four or more days had a significantly higher incidence of SSI (11/62, 17.7%, p = 0.006) than patients with an OCD less than 4 days (6/115, 5.3%).The incidence of SSI following CHS is higher in DSC patients compared to PCC patients. Prolonged OCD of 4 days or more significantly increases the risk of SSI and represents a potentially modifiable risk factor for SSI predisposition. These data support dedicated, daily post-operative assessment of candidacy for chest closure to minimize the risk of SSI.
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Haze problem is an important factor threatening human health. PM2.5 is the main culprit haze. 1-Nitropyrene (1-NP) is the main nitrated polycyclic aromatic hydrocarbon, the toxic component of PM2.5 particles. The effects of 1-NP on various organs and reproductive health have been extensively and deeply studied, but the effects of 1-NP on embryo implantation and endometrial receptivity remain to be determined. The purpose of this study was to investigate the adverse effects of 1-NP on mouse embryo implantation and human endometrial receptivity. In early pregnancy, CD1 mice were given 2 mg/kg 1-NP by oral gavage, which resulted in a decreased embryo implantation number on day 5, inhibited leukemic inhibitory factor (LIF)/STAT3 pathway, decreased expression of estrogen receptor and progesterone receptor, and disrupted regulation of uterine cell proliferation. In addition, in a human in vitro implantation model, 1-NP was found to significantly inhibit the adhesion rate between trophoblast spheroids and endometrial epithelial cells, possibly by inhibiting the expression of receptivity molecules in Ishikawa cells. Promoting reactive oxygen species (ROS) production may be an additional mechanism by which it inhibits trophoblast spheroid adhesion. In this study, we used an in vivo mouse pregnancy model and an in vitro human embryo implantation model to demonstrate that 1-NP can impair endometrial receptivity and compromise embryo implantation.
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Implantação do Embrião , Endométrio , Animais , Feminino , Camundongos , Gravidez , Pirenos , Espécies Reativas de Oxigênio , ÚteroRESUMO
BACKGROUND: Clarithromycin-resistance is becoming a global health concern in the treatment of Helicobacter pylori (H. pylori). The mutant prevention concentration (MPC) represent the propensities of antimicrobial agents to select resistant mutants. The concentration range between the minimum inhibitory concentration (MIC) and the MPC is defined as mutant selection window (MSW). In this study, we aimed to determine the cause of increasing clarithromycin resistance by investigating the MSW for clinical isolates of H. pylori. RESULTS: A retrospective subgroup, which included 68 clarithromycin-sensitive H. pylori strains, was selected from a double-blind trial. The MICs and MPCs were determined using agar plate assays. Genotypic tests were performed using Sanger sequencing. All isolates were wild-type, and 33.82% (23/68) had a 0.016 mg/L MIC, 45.59% (31/68) had a 0.031 mg/L MIC, 16.18% (11/68) had a 0.062 ≤ MIC ≤ 0.125 mg/L, and 4.41% (3/68) had a 0.25 mg/L MIC. The MPC50/90 (mg/L) of the isolates were: 0.062/0.125, 0.125/0.5, 0.25/0.25 and 1/2, respectively. The MPCs showed a moderate correlation with the MICs (rs = 0.65, P < 0.0001). Using published data and MPC90, we calculated the time inside the MSW (TMSW) for low- and high-dose (200 or 500 mg bid) clarithromycin that were 6 and 0 h, 24 and 4 h, 15 and 2 h, 5 and 17 h for the strains with MICs (mg/L) of 0.016, 0.031, 0.062-0.125, and 0.25, respectively. CONCLUSIONS: This study showed that in the clarithromycin-sensitive clinical isolates of H. pylori, low-dose clarithromycin may lead to decreased drug sensitivity or even clarithromycin resistance; strains with a 0.25 mg/L MIC display a high risk of treatment failure.
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Claritromicina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Claritromicina/administração & dosagem , Método Duplo-Cego , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Estudos RetrospectivosRESUMO
Background: Polymyxin B (PMB) and polymyxin E (colistin, CST) are polymyxin antibiotics, which are considered last-line therapeutic options against multidrug-resistant Gram-negative bacteria in serious infections. However, there is increasing risk of resistance to antimicrobial drugs. Effective efflux pump inhibitors (EPIs) should be developed to help combat efflux pump-mediated antibiotic resistance. Methods: Chryseobacterium sp. PL22-22A was isolated from aquaculture sewage under selection with 8 mg/L PMB, and then its genome was sequenced using Oxford Nanopore and BGISEQ-500 platforms. Cpr (Chryseobacterium Polymyxins Resistance) genes encoding a major facilitator superfamily-type tripartite efflux system, were found in the genome. These genes, and the gene encoding a truncation mutant of CprB from which sequence called CprBc was deleted, were amplified and expressed/co-expressed in Escherichia coli DH5α. Minimum inhibitory concentrations (MICs) of polymyxins toward the various E. coli heterologous expression strains were tested in the presence of 2-128 mg/L PMB or CST. The pumping activity of CprABC was assessed via structural modeling using Discovery Studio 2.0 software. Moreover, the influence on MICs of baicalin, a novel MFS EPI, was determined, and the effect was analyzed based on homology modeling. Results: Multidrug-resistant bacterial strain Chryseobacterium sp. PL22-22A was isolated in this work; it has notable resistance to polymyxin, with MICs for PMB and CST of 96 and 128 mg/L, respectively. A novel MFS-type tripartite efflux system, named CprABC, was identified in the genome of Chryseobacterium sp. PL22-22A. Heterologous expression and EPI assays indicated that the CprABC system is responsible for the polymyxin resistance of Chryseobacterium sp. PL22-22A. Structural modeling suggested that this efflux system provides a continuous conduit that runs from the CprB funnel through the CprC porin domain to pump polymyxins out of the cell. A specific C-terminal α-helix, CprBc, has an activation function on polymyxin excretion by CprB. The flavonoid compound baicalin was found to affect the allostery of CprB and/or obstruct the substrate conduit, and thus to inhibit extracellular polymyxin transport by CprABC. Conclusion: Novel MFS-type tripartite efflux system CprABC in Chryseobacterium sp. PL22-22A mediates resistance to polymyxins, and baicalin is a promising EPI.
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This paper proposes to improve the output performance of a piezoelectric pump by matching the resonant frequency of the resonator to the optimal operating mode of bridge-type polydimethylsiloxane (PDMS) check valves. Simulation analyses reveal that the side-curling mode of the PDMS valve is conducive to liquid flow and exhibits a faster frequency response compared with the first bending mode. The first bending resonant frequency of a beam-type piezoelectric resonator was tuned close to the side-curling mode of the PDMS valve by adjusting the weight of two mass blocks installed on both ends of the resonator, so that both the resonator and the valve could work at their best conditions. Experiments were conducted on a detachable prototype piezoelectric pump using PDMS valves with three different lengths. The results confirm that the peak flowrate at the resonant point of the pump reaches its maximum when the resonant frequencies between the resonator and the valve are matched. Maximum peak flowrates of 88 mL/min, 72 mL/min and 70 mL/min were achieved at 722 Hz, 761 Hz and 789 Hz, respectively, for diaphragm pumps using five-, four- and three-inlet-hole PDMS valves, under a driving voltage of 300 Vpp.
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Purpose: C-type lectin domain family 1 member B (CLEC1B) is a protein-coding gene involved in various processes, such as platelet activation, tumor cell metastasis and separation of blood/lymphatic vessels. However, how CLEC1B plays its role in hepatocellular carcinoma (HCC) has not been well studied. The purpose of this study was to investigate the clinical significance and biological function of CLEC1B in HCC. Patients and Methods: Based on (The Cancer Genome Atlas) TCGA database, CLEC1B expression matrix and corresponding clinical information were extracted. ROC curves and Kaplan-Meier method were generated to evaluate the value of CLEC1B as a diagnostic and prognostic biomarker. Moreover, single-gene difference analysis constructed by DESeq2 method and then the related genes were used to predict CLEC1B-related signaling pathways. The ssGSEA algorithm was conducted for studies related to immune infiltration. CLEC1B protein expression was evaluated and immunohistochemistry in HCC tissues through tissue microarray. Finally, the relationship between CLEC1B expression and T cell infiltration was assessed according to tissue microarray. Results: The mRNA and protein levels of CLEC1B were significantly down-regulated in HCC compared to paired normal tissues, which were further verified in clinical tissue samples. ROC curves and Kaplan-Meier survival analysis suggested the significant diagnostic and clinical prognostic value of CLEC1B. Meanwhile, downregulation of CLEC1B was significantly associated with clinical parameters such as clinical tumor vascular invasion and distant metastasis. Moreover, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene set enrichment (GSEA) analysis indicated that CLEC1B has significant association with immune function. Finally, immune infiltration analysis indicated that CLEC1B was significantly associated with immune cell subsets and affected the efficacy of immunotherapy in cancer patient. Conclusion: Collectively, our findings suggested that CLEC1B could be a promising prognostic biomarker in HCC and its expression was related to immune cell infiltration.
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BACKGROUND: Selective antegrade cerebral perfusion (SACP) has become our preferred method for cerebral protection during open arch cases. While the initial approach involved sewing a graft to the innominate artery as the arterial cannulation site, our access strategy has since evolved to central aortic cannulation with use of a percutaneous cannula in the innominate for SACP. We hypothesized that SACP delivered via direct innominate cannulation using a 12- or 14-Fr cannula results in equivalent outcomes to cases utilizing a side graft. METHODS: This was a single-center, retrospective analysis of 211 adult patients who underwent elective hemiarch replacement using hypothermic circulatory arrest with SACP via the innominate artery between 2012 and 2020. Urgent and emergent cases were excluded. RESULTS: A side graft sutured to the innominate was utilized in 81% (n = 171) of patients, while direct innominate artery cannulation was performed in 19% (n = 40) of patients. Baseline patient characteristics were similar between groups aside from a higher baseline creatinine in the direct cannulation group (1.3 vs. 0.9, p = 0.032). Patients undergoing direct cannulation demonstrated shorter cardiopulmonary bypass time (132.7 vs. 154.9 minutes, p = 0.020) and shorter circulatory arrest time (8.1 vs. 10.9 minutes, p = 0.004). Nadir bladder temperature did not significantly differ between groups (27.2°C for side graft vs. 27.6°C for direct cannulation, p = 0.088). There were no significant differences in postoperative outcomes. CONCLUSION: Direct cannulation of the innominate artery with a 12- or 14-Fr cannula for SACP during hemiarch replacement is a safe alternative to using a sutured side graft. While cardiopulmonary bypass and circulatory arrest times appear improved, this is likely attributable to accumulation of experience and proficiency in technique. However, direct innominate artery cannulation may facilitate quicker completion of these procedures by eliminating the time necessary to suture a graft to the innominate artery.
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BACKGROUND: The appropriate stent length in frozen elephant trunk replacements (FET) remains debated relative to the risk for paraplegia. However, landing the distal end of the stent beyond the curve of the arch facilitates distal reintervention, which is commonly beyond the 10 cm stent coverage when deployed proximal to the left subclavian artery. The aim of this study was to evaluate outcomes following the use of 15 cm stent grafts in zone 2 (z2, distal to the left common carotid). METHODS: Using our single institution-maintained database, 103 zone 2 FET performed from 2016 to 2020 were reviewed. RESULTS: Of the 103 z2, a 15 cm stent graft was used in 51 operations. The indications for FET included acute and chronic aortic dissection, arch aneurysms, and pseudoaneurysms. The incidence of SCI was 0%. Seven deaths (13.7%) occurred. CONCLUSIONS: The data demonstrates the incidence of post-operative paraplegia to be 0% with 15 cm z2 FET. The understanding of SCI in FET should not only include the stent length but also from where it begins.
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Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Isquemia do Cordão Espinal , Aorta Torácica , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Humanos , Paraplegia/etiologia , Paraplegia/cirurgia , Estudos Retrospectivos , Isquemia do Cordão Espinal/complicações , Isquemia do Cordão Espinal/etiologia , Stents/efeitos adversos , Resultado do TratamentoRESUMO
Herein, magnetic nitrogen doped porous biochar (Fe/N-PBC) was prepared by mixing KHCO3, K2FeO4 and CO(NH2)2 through one-step pyrolysis, and was employed for adsorbing Cr(VI) and BPA in water. The whole co-activated process was accompanied with pore-forming, carbon thermal reduction and element doping. Specifically, the developed microporous structures and high surface area of Fe/N-PBC (1093.68 m2/g) were achieved under synergistic activation of KHCO3 and K2FeO4. Meanwhile, carbon thermal reduction process successfully converted K2FeO4 to Fe0 with introduction of heterocyclic-N (pyrrolic N and pyridinic N) structures by CO(NH2)2 doping. Fe/N-PBC exhibited outstanding uptake for Cr(VI) (340.96 mg/g) and BPA (355.14 mg/g), and possessed favorable regeneration properties after three cycles. Notably, the high-performance Cr(VI) removal was associated to reduction, electrostatic interaction, complexation, pore filling and ion exchange, while pore filling, hydrogen-bonding interaction and π-π stacking were responsible for BPA binding. This work presents reasonable design of Fe/N-carbon materials for Cr(VI)/BPA polluted water remediation.
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Poluentes Químicos da Água , Água , Adsorção , Compostos Benzidrílicos , Carbono/química , Carvão Vegetal/química , Cromo/química , Descontaminação , Fenóis , Porosidade , Poluentes Químicos da Água/químicaRESUMO
Herein, polyethylenimine-grafted nanocellulose (PEIMW@NCMW) was synthetized through microwave-assisted synthesis, which was employed for Pb(II) and phosphate scavenging from water. Characterization results exhibited that the original pomegranate peel-derived cellulose could be transformed to nanometer level by microwave radiation and the amino groups were successfully grafted on the nanocellulose evenly. The adsorption performance of PEIMW@NCMW possessed outstanding improvements over that of original nanocellulose with maximum adsorption capacities reaching 916.02 mg/g for Pb(II) and 278.89 mg/g for phosphate. Furthermore, the PEIMW@NCMW had high tolerance to various co-existing ions and could maintain over 94% removal efficiency during four regeneration cycles. Additionally, the Pb(II) uptake onto PEIMW@NCMW was associated with electrostatic attraction, complexation and pore-filling, whereas high phosphate capture was achieved via H-bonding, complexation and electrostatic attraction. In summary, PEIMW@NCMW was deemed as a potential adsorbent with excellent adsorption capacity for remediation of Pb(II) and phosphate polluted water.
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Fosfatos , Poluentes Químicos da Água , Adsorção , Cinética , Chumbo , Micro-Ondas , Polietilenoimina , Água , Poluentes Químicos da Água/análiseRESUMO
Francisella tularensis is a dangerous pathogen that causes an extremely contagious zoonosis in humans named tularemia. Given its low-dose morbidity, the potential to be fatal, and aerosol spread, it is regarded as a severe threat to public health. The US Centers for Disease Control and Prevention (CDC) has classified it as a category A potential agent for bioterrorism and a Tier 1 Select Agent. Herein, we combined recombinase polymerase amplification (RPA) with CRISPR/Cas12a system to select the F. tularensis target gene (TUL4), creating a two-pronged rapid and ultrasensitive diagnostic method for detecting F. tularensis. The real-time RPA (RT-RPA) assay detected F. tularensis within 10 min at a sensitivity of 5 copies/reaction, F. tularensis genomic DNA of 5 fg, and F. tularensis of 2 × 102 CFU/ml; the RPA-CRISPR/Cas12a assay detects F. tularensis within 40 min at a sensitivity of 0.5 copies/reaction, F. tularensis genomic DNA of 1 fg, and F. tularensis of 2 CFU/ml. Furthermore, the evaluation of specificity showed that both assays were highly specific to F. tularensis. More importantly, in a test of prepared simulated blood and sewage samples, the RT-RPA assay results were consistent with RT-PCR assay results, and the RPA-CRISPR/Cas12a assay could detect a minute amount of F. tularensis genomic DNA (2.5 fg). There was no nonspecific detection with blood samples and sewage samples, giving the tests a high practical application value. For example, in on-site and epidemic areas, the RT-RPA was used for rapid screening and the RPA-CRISPR/Cas12a assay was used for more accurate diagnosis.
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BACKGROUND: Data on recurrence are important to inform surveillance and improve long-term surgical outcomes for patients with hepatocellular carcinoma. We sought to identify risk factors and long-term prognosis among patients who experienced beyond-Milan recurrence after hepatectomy for early-stage hepatocellular carcinoma. METHODS: Patients who underwent hepatectomy for Barcelona Clinic Liver Cancer stage 0/A hepatocellular carcinoma were identified from a multi-institutional database. Predictors of beyond-Milan recurrence and risk factors associated with post-recurrence survival among patients with beyond-Milan recurrence were assessed using univariate and multivariate Cox regression analyses. RESULTS: Among 753 patients (median follow-up, 51.8 months), 138 (18.3%) developed beyond-Milan recurrence. Regular surveillance (interval follow-up ≤3 months within 1 year and ≤6 months in subsequent years after surgery) was not carried out for 53 (38.4%) patients who developed beyond-Milan recurrence. On multivariate analysis, increased risk of beyond-Milan recurrence was independently associated with preoperative alpha-fetoprotein level >400 ng/mL, tumor size >5.0 cm, multifocal disease, microvascular invasion, and no/irregular recurrence surveillance. Median post-recurrence survival among patients with beyond-Milan recurrence was only 8.4 months (95% confidence interval: 7.0-9.8 months). Among patients who developed beyond-Milan recurrence, Child-Pugh grade B/C, early recurrence within 1 year after surgery, macrovascular invasion/distant metastasis, and noncurative treatment of recurrence were independent risk factors associated with worse post-recurrence survival. CONCLUSION: Nearly 1 in 5 patients developed beyond-Milan recurrence after hepatectomy for early-stage hepatocellular carcinoma. Patients with beyond-Milan recurrence had a median survival of less than 1 year after diagnosis of the recurrence. Regular surveillance is an important and actionable measure to decrease beyond-Milan recurrence and, in turn, improve long-term survival among patients treated with hepatectomy for hepatocellular carcinoma.