Capacidad pronóstica del dímero D en la predicción de mortalidad en pacientes con el diagnóstico de COVID-19 / Pronostic capacity of D-dimer in predicting mortality in patients diagnosed with COVID-19

RESUMEN Introducción: La infección por SARS-CoV-2 puede aumentar el riesgo de trombosis. Estudios asocian niveles de dímero D con mortalidad por COVID-19. Objetivo: Determinar la capacidad pronostica del dimero D en la predicción de mortalidad por COVID-19 en pacientes hospitalizados en la Unidad de Cuidados Intensivos. Métodos: Se realizó un estudio de cohorte retrospectiva en el Centro Médico Naval durante enero-julio de 2021. Se incluyeron 324 pacientes adultos con COVID-19 confirmada por RT-PCR. Se midieron niveles de dímero D al ingreso utilizando turbidimetría de coagulación (Sysmex CS-5100). Se analizaron variables sociodemográficas, comorbilidades y datos clínicos. El análisis estadístico se realizó con SPSS versión 26, empleando pruebas Chi cuadrado, exacta de Fisher, U de Mann Whitney, COR y regresión de Cox. Resultados: Se determinó un punto de corte de 1,40 µg/mL para los valores de dimero D con una sensibilidad de 80,9%, una especificidad de 86,4% y área bajo la curva (AUC) de 0,916 (IC 95%: 0,884 - 0,947; p =0,016) para predecir mortalidad por COVID-19. Asimismo, se encontró que pacientes con valores de dimero D mayores o iguales a 1,40 µg/mL tenian un riesgo incrementado de fallecimiento en pacientes con COVID-19 (HRa = 6,545; IC 95%: 3,867 - 11,077; p<0,001), independientemente de las variables edad, diabetes mellitus, hipertensión arterial, cardiopatía isquémica, enfermedad cerebrovascular, fibrilación auricular, enfermedad pulmonar obstructiva crónica, asma, cáncer y trombocitopenia. Conclusión: El presente estudio mostró que los niveles de dimero D al ingreso representan un biomarcador fiable en la evaluación del pronostico de pacientes con COVID-19.

ABSTRACT Introduction: SARS-CoV-2 infection can increase the risk of thrombosis. Studies associate D-dimer levels with COVID-19 mortality. Objective: To determine the prognostic capacity of D-dimer in predicting COVID-19 mortality in patients hospitalized in the Intensive Care Unit. Methods: A retrospective cohort study was conducted at the Naval Medical Center from January to July 2021. A total of 324 adult patients with RT-PCR confirmed COVID-19 were included. D-dimer levels were measured upon admission using coagulation turbidimetry (Sysmex CS-5100). Sociodemographic variables, comorbidities, and clinical data were analyzed. Statistical analysis was performed using SPSS version 26, employing Chi-square tests, Fisher's exact test, Mann-Whitney U test, ROC, and Cox regression. Results: A cut-off point of 1.40 µg/mL for D-dimer values was determined, with a sensitivity of 80.9%, specificity of 86.4%, and an area under the curve (AUC) of 0.916 (95% CI: 0.884 - 0.947; p=0.016) for predicting COVID-19 mortality. Additionally, patients with D-dimer values greater than or equal to 1.40 µg/mL had an increased risk of death (adjusted HR = 6.545; 95% CI: 3.867 - 11.077; p<0.001), independent of age, diabetes mellitus, arterial hypertension, ischemic heart disease, cerebrovascular disease, atrial fibrillation, chronic obstructive pulmonary disease, asthma, cancer, and thrombocytopenia. Conclusion: This study showed that admission D-dimer levels represent a reliable biomarker in evaluating the prognosis of COVID-19 patients. Keywords: COVID-19; SARS-CoV-2; Mortality; Fibrin-Fibrinogen Degradation Products (Source: MeSH NLM).

In vitro degradation behavior of Mg-Zn-Ca alloys / 中国组织工程研究

BACKGROUND:Due to the complex physiological environment of the human body,a wide variety of simulated physiological fluids have been chosen for the current degradation experiments.Therefore,it is of great interest to analyze the degradation behavior of Mg-Zn-Ca alloys in different simulated body fluid environments. OBJECTIVE:To investigate the degradation process and property changes of Mg-Zn-Ca alloy in different simulated body fluids,and to clarify the influence of Ca content and simulated body fluid type on the alloy. METHODS:Mg-Zn-Ca alloys with calcium content of 0.2%,0.5%and 1%were prepared by melting extrusion molding process and were named Mg-Zn-0.2Ca,Mg-Zn-0.5Ca and Mg-Zn-1Ca alloys in turn,with Mg-Zn alloy as the control.The prepared alloys were placed into three simulated body liquids(physiological saline,PBS and Hank's solution),and the morphology,compositional changes,mass loss,pH value and mechanical properties were characterized and analyzed during the degradation. RESULTS AND CONCLUSION:(1)With the extension of degradation time,a large number of nanoscale lamellae and columnar structures were generated on the surface of the degraded alloy,and the main components were MgO and Mg(OH)2.The degradation rate of the four kinds of alloys in physiological saline was the fastest,and that in Hank's solution was the slowest.The degradation rate in physiological saline was as follows:Mg-Zn<Mg-Zn-0.2Ca<Mg-Zn-0.5Ca<Mg-Zn-1Ca.The degradation rate in PBS and Hank's solution was as follows:Mg-Zn<Mg-Zn-0.2Ca ≈ Mg-Zn-0.5Ca<Mg-Zn-1Ca.(2)With the extension of degradation time,all four kinds of alloys had a certain mass loss.The degradation in physiological saline was the fastest;the degradation in Hank's solution and PBS was slow,and in the same simulated body fluid,with the increase of calcium content in the alloy,the corrosion rate of the alloy was obviously accelerated.(3)The pH rise was mainly concentrated in 1 day and slowed down after that,and the pH change was the largest in PBS.In the same simulated body fluid,with the increase of calcium content in the alloy,the pH value in the degradation environment increased significantly.(4)In the initial state,the elastic modulus of all Mg-Zn-Ca alloys was higher than that of Mg-Zn alloys.After being placed in simulated body fluids,the elastic modulus of the four alloys decreased with the extension of degradation time,and the decrease was most obvious in physiological saline.(5)In conclusion,a small amount of Ca addition improved the mechanical properties of Mg-Zn-Ca alloy.A small amount of Ca does not accelerate the degradation rate of the alloy,but excessive Ca accelerates the degradation rate of the alloy.During the degradation,the effect of physiological saline simulated body fluid on the mechanical strength of the alloy was the most significant.

Mechanism and influencing factors in molecular weight degradation of non-cross-linked hyaluronic acid / 中国组织工程研究

BACKGROUND:The structure,physical and chemical properties(such as rheological properties)and biological activity of hyaluronic acid with different molecular weights are quite different.When the degradation degree of non-cross-linked hyaluronic acid is too large and the high-molecular-weight hyaluronic acid is degraded to low-molecular-weight hyaluronic acid,the properties and biological functions of the product will also change,which will affect the use of the product. OBJECTIVE:To review the mechanism of molecular weight degradation of non-cross-linked hyaluronic acid and the impacts of molecular weight degradation on the structure,rheological properties,biological activity and applications of non-cross-linked hyaluronic acid. METHODS:The first author searched the articles related to the molecular weight of hyaluronic acid collected in PubMed,CNKI database and other databases.The high-quality articles with high correlation were screened according to the inclusion and exclusion criteria.The search time was from January 2017 to December 2022.The Chinese and English search terms were"hyaluronic acid,non-cross-linked hyaluronic acid,molecular weight,degradation,structure,rheological properties,biologic activity".Finally,47 articles were included for review and analysis. RESULTS AND CONCLUSION:(1)The molecular weight of non-cross-linked hyaluronic acid is mainly degraded by specific enzymatic hydrolysis and non-specific free radical degradation.(2)The molecular weight degradation of non-cross-linked hyaluronic acid will change its structure and rheological properties,resulting in the untie of polymer network structure,the decrease of rheological properties such as viscosity and viscoelasticity,and the decrease of mechanical properties,which will eventually affect the practical application effect of the product.(3)The biological activity of non-cross-linked hyaluronic acid is molecular weight dependent,and the biological activity of different molecular weight hyaluronic acid is different.Even the same receptor combined with high-molecular-weight hyaluronic acid and low-molecular-weight hyaluronic acid will express completely opposite biological effects.(4)The degradation of molecular weights of non-cross-linked hyaluronic acid will reduce the safety and efficacy of the products,affect their service life and application performance,and ultimately influence the clinical application results.(5)Non-cross-linked hyaluronic acid has great potential as a biodegradable biomaterial in wound healing,tissue engineering,aesthetic medicine and other fields,and further research and understanding of the correlation between molecular weight degradation of non-cross-linked hyaluronic acid and bioactivity is a prerequisite for better development of wound dressings,drug delivery systems and tissue-engineered scaffolds.(6)However,there are currently few studies on the molecular weight degradation of non-cross-linked hyaluronic acid,and it is unclear how to effectively avoid the potential risks associated with the molecular weight degradation of non-cross-linked hyaluronic acid in clinical applications.(7)Therefore,a series of potential risks associated with the molecular weight degradation of non-cross-linked hyaluronic acid during its application,including the effects on its structure,properties and biological activity,and the resulting changes on the body,is one of the future directions that need to be closely investigated.

Application of strontium polyphosphate with both radiopaque and osteogenic functions in calcium phosphate cement / 中国组织工程研究

BACKGROUND:Our previous studies found that adding barium sulfate could improve the mechanical and radiopaque properties of calcium phosphate cement.However,with the degradation of calcium phosphate,the remaining radiopaque agent is difficult to degrade,and the space-occupying and osteoclast effects at the implantation site affect the bone repair process.Therefore,it is necessary to develop a new biodegradable radiopaque material. OBJECTIVE:To discuss the radiopaque ability of bioactive degradable material strontium polyphosphate(SrPP)and its impact on the physicochemical properties and osteogenic effect of calcium phosphate cement. METHODS:(1)Calcium phosphate cement(CPC),starch modified calcium phosphate cement(CPS)and starch modified calcium phosphate cement(20%SrPP-CPN)containing SrPP(20%mass fraction of bone cement powder)were prepared respectively,and the physicochemical properties of the three groups of bone cements were characterized.(2)The three groups of bone cement extracts were co-cultured with rat bone marrow mesenchymal stem cells,respectively,to detect cell proliferation,energy metabolism,and osteogenic differentiation.(3)Bone defects with a diameter of 5 mm were made on each side of the top of the skull of 24 SD rats,and they were randomly divided into control group(without any intervention),CPC group,CPS group,and 20%SrPP-CPN group for intervention,with 6 rats in each group.Relevant tests were performed after 4 and 12 weeks of intervention. RESULTS AND CONCLUSION:(1)Compared with the other two groups of bone cement,20%SrPP-CPN had enhanced radiopaque ability,increased compressive strength and degradation rate,and prolonged curing time,and 20%SrPP-CPN could release Sr2+ stably during degradation.(2)CCK-8 assay showed that 20%SrPP-CPN did not affect the proliferation of bone marrow mesenchymal stem cells.Cell starvation test(serum-free culture)showed that 20%SrPP-CPN could promote the proliferation of bone marrow mesenchymal stem cells compared with the other two groups of bone cement.Compared with the other two groups of bone cements,20%SrPP-CPN increased adenosine triphosphate concentration in bone marrow mesenchymal stem cells.Alkaline phosphatase and alizarin red staining showed that 20%SrPP-CPN could promote osteogenic differentiation of bone marrow mesenchymal stem cells compared with the other two groups of bone cement.(3)In the rat skull defect experiment,Micro-CT scanning and histological observation(hematoxylin-eosin and Masson stainings)showed that bone cement in 20%SrPP-CPN group was significantly degraded compared with that in CPC and CPS groups,and a large number of new bone tissues were dispersed in degraded bone cement.Immunohistochemical staining showed that Runx2 protein expression was increased in 20%SrPP-CPN group compared with CPC group and CPS group(P＜0.01).(4)These results show that 20%SrPP-CPN has good radiopaque ability and osteogenic properties.

Establishment and validation of the Sprague-Dawley rat model of osteoarthritis with kidney deficiency and blood stagnation / 中国组织工程研究

BACKGROUND:Kidney deficiency and blood stasis syndrome are common traditional Chinese medicine syndromes observed in knee osteoarthritis,which serve as fundamental pathogenesis factors.There exists a significant connection between the two.Previous studies have demonstrated that kidney deficiency and blood stasis syndrome effectively contribute to knee joint cartilage degeneration and the progression of knee osteoarthritis.However,the mechanisms underlying the promotion of knee joint cartilage damage remain unclear and require further investigation. OBJECTIVE:To investigate the influence of kidney deficiency and blood stasis syndrome on the progression of knee osteoarthritis in Sprague-Dawley rats. METHODS:Sixteen Sprague-Dawley rats were randomly divided into two groups:a model observation group and a control group,with eight rats in each group.Animal models of kidney deficiency were induced by ovary removal in the model observation group,while the control group was given a sham procedure for ovarian removal.Two months after modeling,both groups underwent modified HULTH surgery to induce knee osteoarthritis.One week after modified HULTH surgery,the model observation group was subcutaneously given adrenaline hydrochloride to make blood stasis models,while the control group was subcutaneously given normal saline.At the 5th week after modified HULTH surgery,blood rheology,coagulation parameters,triiodothyronine,tetraiodothyronine,and estradiol levels were measured.Knee joint X-ray images were taken,and knee joint sections were stained with safranin O-fast green,hematoxylin-eosin,and immunohistochemistry. RESULTS AND CONCLUSION:Compared with the control group,the model observation group exhibited significant increases in whole blood viscosity at low,medium,and high shear rates,as well as increased plasma viscosity.Fibronectin levels in the coagulation parameters were significantly increased,while prothrombin time and activated partial thromboplastin time were significantly decreased.Triiodothyronine,tetraiodothyronine,and estradiol levels were all significantly decreased.Radiographic results showed that the model observation group exhibited more severe degree of knee joint space narrowing and surface roughness,with the appearance of high-density shadows.Hematoxylin-eosin and safranin O-fast green staining demonstrated more severe cartilage damage in the model observation group,with significantly higher OARSI and Mankin scores compared with the control group.Compared with the control group,immunohistochemistry results showed a significant reduction in the expression of extracellular matrix type II collagen and aggrecan protein in the cartilage of the model observation group rats.Moreover,there was a significant increase in the expression of matrix metalloproteinase 13 and aggrecanase 5,which are inflammatory factors.These results indicate that the Sprague-Dawley rat model of knee osteoarthritis with kidney deficiency and blood stasis was successfully established.Kidney deficiency and blood stasis syndrome further aggravate cartilage extracellular matrix degradation and cartilage degeneration by promoting the expression of inflammatory factors,thereby promoting the progression of knee osteoarthritis in rats.

Network pharmacology and molecular docking to study the mechanism of action of alpinumisoflavone in a temporomandibular joint osteoarthritis cell model / 口腔疾病防治

Objective@#To explore the potential role of alpinumisoflavone (AIF) in the treatment of temporomandibular joint osteoarthritis (TMJOA) cell model through network pharmacology and molecular docking and to provide a research basis for AIF in the treatment of TMJOA.@*Methods@#GeneCards, OMIM, DisGeNET, and PharmGKB databases were used to screen TMJOA disease targets, and PharmMapper and HERB were used to retrieve AIF-related targets. The intersection targets of the compounds and diseases were uploaded to the STRING database to obtain the key targets for GO and KEGG enrichment analysis, while the key targets in related signaling pathways were evaluated through molecular docking. Approval was obtained from the Ethics Committee to extract condylar chondrocytes from 3-week-old SD rats. The CCK-8 assay was used to detect AIF cytotoxicity on condylar chondrocytes. Condylar chondrocytes were induced with 10 ng/mL interleukin 1β (IL-1β) for 24 h to construct a TMJOA cell model. The experiment was divided into three groups: control group, comprising condylar chondrocytes cultured in DMEM for 48 h; IL-1β group, comprising condylar chondrocytes pre-cultured in DMEM for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h; and the IL-1β+10 μmol/L AIF group, comprising condylar chondrocytes pre-cultured in DMEM medium containing 10 μmol/L AIF for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h. The effect of AIF on condylar chondrocyte apoptosis in the TMJOA cell model was detected by flow cytometry. The experiment was divided into four groups: control group, IL-1β group, IL-1β+10 μmol/L AIF group, and IL-1β+30 μmol/L AIF group. The IL-1β+30 μmol/L AIF group was pre-cultured in DMEM containing 30 μmol/L AIF for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h. The remaining three groups were cultured in the same manner as before. The mRNA and protein expression of apoptosis-associated B-cell leukemia/lymphoma-2 (Bcl2), cysteinyl aspartate specific protease 3 (caspase-3), matrix degradation-associated a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4), matrix metalloproteinase 3 (MMP3), and matrix metalloproteinase 13 (MMP13) were detected by qPCR and western blot, by AIF in the TMJOA cell model.@*Results@#The PharmMapper and HERB database search yielded 300 AIF compound targets. The GeneCards, OMIM, DisGeNET, and PharmGKB databases yielded 378 TMJOA disease targets. Thirty-three potential common targets were obtained by intersecting compounds with disease targets. The common targets were uploaded into the STRING database to obtain 31 key targets that were mainly associated with apoptosis and extracellular matrix degradation. This process may be associated with the MAPK, estrogen, and TNF signaling pathways. The molecular docking results showed that AIF has good binding activity with extracellular signal-regulated kinase 1/2 (ERK1/2) and estrogen receptor gene 1/2 (ESR1/2), which are key targets in the MAPK and estrogen signaling pathways. The CCK-8 assay showed that AIF had no obvious cytotoxicity to condylar chondrocytes. The cell experiments showed that AIF inhibited apoptosis in the IL-1β+10 μmol/L AIF group compared to the IL-1β group. Compared to the IL-1β group in the IL-1β+10 μmol/L AIF group and the IL-1β+30 μmol/L AIF group, AIF upregulated Bcl2 and downregulated caspase-3 mRNA and protein expression and inhibited ADAMTS4, MMP3, and MMP13 mRNA and protein expression.@*Conclusion@#AIF inhibited apoptosis in the TMJOA cell model by upregulating Bcl2 and downregulating caspase-3 mRNA and protein expression, and inhibited extracellular matrix degradation induced by IL-1β, thereby delaying TMJOA progression.

The repressing effect of fenoldopam on the development of thoracic aortic aneurysm in mice / 安徽医科大学学报

Objective @#To investigate whether fenoldopam (FNDP) ( an agonist of type 1 dopamine receptor) has a protective effect on thoracic aortic aneurysm ( TAA) in mice .@*Methods @#Three-week-old male C57BL/6J mice were treated with β-aminopropionitrile (BAPN) to induce TAA . The mice were divided into three groups : the con- trol group , the BAPN group , and the BAPN + FNDP group (FNDP inj ected intraperitoneally) . The incidence and survival rate of TAA were recorded . Gross anatomy of the whole aortae was ob served . Elastin staining was per- formed to assess morphological change , while immunohistochemistry was employed to evaluate the expressions of matrix metalloproteinase 2(MMP2) , matrix metalloproteinase 9( MMP9) and cluster of differentiation 68( CD68) respectively. Gelatin zymography was conducted to assess MMP2 and MMP9 activity. Reverse transcription-poly- merase chain reaction (RT-PCR) was performed to measure the mRNA expression levels of dopamine receptor D1(D1DR) , dopamine receptor d2 (D2DR) , dopamine receptor d3 (D3DR) , dopamine receptor d5 (D5DR) , in- terleukin-1β(IL-1β) , interleukin-6 (IL-6) , tumour necrosis factor-α (TNF-α) , monocyte chemoattractant pro- tein-1 (MCP-1) , alpha-smooth muscle actin ( α-SMA) and smooth muscle protein 22 -alpha (SM22α) .@*Results@#Compared to the control group , the BAPN group exhibited significant formation of TAA . Elastic fiber disruption was also ob served in the thoracic aortic wall , along with a significant decrease in the mRNA levels of D1DR and D5DR. The BAPN + FNDP group showed a significant reduction in the incidence of TAA formation and the rate of aneu- rysm rupture compared to the BAPN group . The disruption and rupture of elastic fibers in the thoracic aortic wall were significantly improved in the BAPN + FNDP group . The levels of MMP2 and MMP9 in the thoracic aortic wall significantly decreased , and the enzymatic activity of MMP2 in the serum was significantly reduced . Moreover , macrophage infiltration in the thoracic aortic wall was significantly reduced and the mRNA levels of IL-1β, IL-6 , TNF-αand MCP-1 also significantly decreased after FNDP treatment. There was no statistically significant differ- ence in the mRNA levels of α-SMA and SM22α.@*Conclusion @#FNDP shows an inhibitory effect on TAA progres- sion in mice , suggesting a potential of FNDP as a therapeutic agent for TAA .

Research progress and potential medical applications of anaplastic lymphoma kinase in treatment of non-small cell lung cancer / 中国药理学通报

During the treatment of non-small cell lung cancer ( NSCLC) , many patients have developed drug resistance due to the use of targeted EGFR inhibitors. The main reasons for drug resistance are EGFR site mutations and bypass activation. Activation of ALK pathway is one of the major types of bypass activation. A recent authoritative study indicates that ALK is closely related to immunotherapy. This article reviews the treatment of ALK in tumors from three aspects: the structure and physiological function of ALK, the small molecule inhibitor of ALK, the biological function of ALK and its related treatment methods for NSCLC, and prospects future directions for better application of ALK in the treatment of NSCLC.

Decoding the Cellular Trafficking of Prion-like Proteins in Neurodegenerative Diseases / 神经科学通报·英文版

The accumulation and spread of prion-like proteins is a key feature of neurodegenerative diseases (NDs) such as Alzheimer's disease, Parkinson's disease, or Amyotrophic Lateral Sclerosis. In a process known as 'seeding', prion-like proteins such as amyloid beta, microtubule-associated protein tau, α-synuclein, silence superoxide dismutase 1, or transactive response DNA-binding protein 43 kDa, propagate their misfolded conformations by transforming their respective soluble monomers into fibrils. Cellular and molecular evidence of prion-like propagation in NDs, the clinical relevance of their 'seeding' capacities, and their levels of contribution towards disease progression have been intensively studied over recent years. This review unpacks the cyclic prion-like propagation in cells including factors of aggregate internalization, endo-lysosomal leaking, aggregate degradation, and secretion. Debates on the importance of the role of prion-like protein aggregates in NDs, whether causal or consequent, are also discussed. Applications lead to a greater understanding of ND pathogenesis and increased potential for therapeutic strategies.

Test of the ability of HPV L1 conserved sequence polypeptide to antisera to degrade HPV6 infection / 中国免疫学杂志

Objective:To determine whether human papillomavirus(HPV L1)C-terminal conserved sequence antibodies with cross-reactive major capsid proteins of different types of HPV L1 have the ability to degrade HPV6 infection.Methods:Condyloma specimens were collected,HPV6 infection cases were identified from the collected samples,and virus was extracted.Polypeptide anti-sera were diluted in different proportions,and then co-cultured and neutralized with the resulting virus,then removed to contact mono-layer-cultured human immortalized keratinocytes and tested by HPV6 disease using PCR.Content of HPV6 DNA in human immortalized keratinocytes was exposed,and the presence of HPV6 L1 protein in this cells was tested by ELISA.Results:Human immortalized ke-ratinocytes infected with HPV6 virus neutralization at different dilution concentrations,the PCR products of their DNA extracts were electrophoresis and showed positive bands of HPV6 specificity zone at 280 bp of the gel,and the intensity of positive bands gradually decreased with increasing antiserum concentration.Protein extracted from human immortalized keratinocytes exposed to anti-serum neutralizing virus was tested by ELISA,and the amount of HPV L1 protein showed the same gradient trend as the above PCR test results,and the difference were statistically significant.Conclusion:It is preliminarily proved that HPV6 L1 conserved sequence polypeptide antisera can partially degrade the infection ability of the virus,and it has the value of studying more HPV neutralization types.

Importancia biológica de la microcistina en aguas de riego y alternativas en su detección y degradación / Biological importance of microcistin in irrigation and alternative waters in its detection and degradation

Introducción: Las cianobacterias son microrganismos fotosintéticos, con capacidad de sintetizar una gran diversidad de metabolitos secundarios de interés para la industria, pero también han llamado la atención en las últimas décadas las toxinas denominas cianotoxinas, metabolitos que causan distintas alternaciones fisiológicas hasta llegar ocasionar la muerte de diferentes especies. Metodología: La determinación del estado de arte para el tema de cianobacterias se basó en una búsqueda bibliográfica en la base de datos especializada como Elservier, Springer, Google académico y MDPI basadas en palabras clave en español e inglés "microcistinas", "degradación de MC" y "cuantificación y detección de MC". Resultados: En la presente revisión considera dos áreas de caracterización de la microcistinas (MCs) las propiedades fisicoquímicas y propiedades biológicas, para entender su comportamiento e importancia tóxica en los sembradíos agrícolas y en la salud humana. Además de comprender alternativas para su degradación, por métodos fisicoquímicos como fotocatálisis y la gradación biológica por bacterias. Finalmente se mencionará algunos métodos actuales y en desarrollo, para la detección y cuantificación de estas MCs en ambientes acuáticos. Conclusiones: Las MCs tienen el potencial contaminar fuentes de agua como ríos y lagunas, causando daños a la salud humana y a las plantas agrícolas, tienen la capacidad de tolerar distintos cambios drásticos en factores fisicoquímicos y biológicos. Entre las alternativas reportadas la degradación bacteriana promete ser la más confiable. Finalmente, entre los distintos métodos para la detección de MCs, entre los métodos más aplicados son los inmunoensayos, debido a su versatilidad y estabilidad del método.

Introduction: Cyanobacteria are photosynthetic microorganisms, with the capacity to synthesize a great diversity of secondary metabolites of interest to the industry, but toxins called cyanotoxins have also attracted attention in recent decades, metabolites that cause different physiological alterations until they cause the death of different species. Methodology: The determination of the state of the art for the subject of cyanobacteria was based on a bibliographic search in specialized databases such as Elservier, Springer, Google Scholar and MDPI based on keywords in Spanish and English "microcystins", "MC degradation " and "quantification and detection of MC". Results: In the present review, two areas of characterization of microcystins are considered: the physicochemical properties and biological properties of microcystins (MC), to understand their behavior and toxic importance in agricultural crops and in human health.In addition to understanding alternatives for their degradation, by physicochemical methods such as photocatalysis and biological grading by bacteria.Finally, some current and developing methods will be mentioned for the detection and quantification of these MCs in aquatic environments. Conclusions: MCs have the potential to contaminate water sources such as rivers and lagoon, causing damage to human health and agricultural plants, they have the ability to tolerate different drastic changes in physicochemical and biological factors. Among the reported alternatives, bacterial degradation promises to be the most reliable. Finally, among the different methods for the detection of MCs, among the most applied methods are immunoassays, due to their versatility and stability of the method.

Research progress of targeted degradation of Mycobacterium tuberculosis proteins / 药学学报

Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis (Mtb), is still one of the significant threats to human life. In recent years, the continuous exploration of small molecule inhibitors represented by bedaquinoline has brought new vitality into the field of tuberculosis. However, small molecule inhibitors will inevitably occur acquired drug resistance during clinical medication. As a new pharmacological mechanism, targeted protein degradation (TPD) achieves efficacy by destroying rather than inhibiting protein targets. It might be an excellent strategy to develop anti-tuberculosis drugs based on the TPD concept to solve drug resistance. This article reviews the protein degradation pathways of Mtb, such as the Pup proteasome system and the ClpP-ClpC1 complex enzyme system. The future development of these strategies into TPD drugs was prospected and summarized.

Opportunities, challenges and suggestions for the development of plastic degradation and recycling under the context of circular bioeconomy / 生物工程学报

At present, the negative impact caused by white pollution has spread to all aspects of human society economy, ecosystem, and health, which causes severe challenges for developing the circular bioeconomy. As the largest plastic production and consumption country in the world, China has shouldered an important responsibility in plastic pollution control. In this context, this paper analyzed the relevant strategies of plastic degradation and recycling in the United States, Europe, Japan and China, measured the literature and patents in this field, analyzed the status quo of technology from the perspective of research and development trends, major countries, major institutions, and discussed the opportunities and challenges faced by the development of plastic degradation and recycling in China. Finally, we put forward future development suggestions which include the integration of policy system, technology path, industry development and public cognition.

Synthesis, biodegradation and waste disposal of polylactic acid plastics: a review / 生物工程学报

With the escalation of plastic bans and restrictions, bio-based plastics, represented by polylactic acid (PLA), have become a major alternative to traditional plastics in the current market and are unanimously regarded as having potential for development. However, there are still several misconceptions about bio-based plastics, whose complete degradation requires specific composting conditions. Bio-based plastics might be slow to degrade when it is released into the natural environment. They might also be harmful to humans, biodiversity and ecosystem function as traditional petroleum-based plastics do. In recent years, with the increasing production capacity and market size of PLA plastics in China, there is an urgent need to investigate and further strengthen the management of the life cycle of PLA and other bio-based plastics. In particular, the in-situ biodegradability and recycling of hard-to-recycle bio-based plastics in the ecological environment should be focused. This review introduces the characteristics, synthesis and commercialization of PLA plastics, summarizes the current research progress of microbial and enzymatic degradation of PLA plastics, and discusses their biodegradation mechanisms. Moreover, two bio-disposal methods against PLA plastic waste, including microbial in-situ treatment and enzymatic closed-loop recycling, are proposed. At last, the prospects and trends for the development of PLA plastics are presented.

Advances in biodegradation of polyolefin plastics / 生物工程学报

Polyolefin plastics are a group of polymers with C-C backbone that have been widely used in various areas of daily life. Due to their stable chemical properties and poor biodegradability, polyolefin plastic waste continues to accumulate worldwide, causing serious environmental pollution and ecological crises. In recent years, biological degradation of polyolefin plastics has attracted considerable attention. The abundant microbial resources in the nature offer the possibility of biodegradation of polyolefin plastic waste, and microorganisms capable of degrading polyolefin have been reported. This review summarizes the research progress on the biodegradation microbial resources and the biodegradation mechanisms of polyolefin plastics, presents the current challenges in the biodegradation of polyolefin plastics, and provides an outlook on future research directions.

Polyethylene biodegradation: current status and perspectives / 生物工程学报

Polyethylene (PE) is the most abundantly used synthetic resin and one of the most resistant to degradation, and its massive accumulation in the environment has caused serious pollution. Traditional landfill, composting and incineration technologies can hardly meet the requirements of environmental protection. Biodegradation is an eco-friendly, low-cost and promising method to solve the plastic pollution problem. This review summarizes the chemical structure of PE, the species of PE degrading microorganisms, degrading enzymes and metabolic pathways. Future research is suggested to focus on the screening of high-efficiency PE degrading strains, the construction of synthetic microbial consortia, the screening and modification of degrading enzymes, so as to provide selectable pathways and theoretical references for PE biodegradation research.

Advances in poly(ethylene terephthalate) hydrolases / 生物工程学报

Plastics have brought invaluable convenience to human life since it was firstly synthesized in the last century. However, the stable polymer structure of plastics led to the continuous accumulation of plastic wastes, which poses serious threats to the ecological environment and human health. Poly(ethylene terephthalate) (PET) is the most widely produced polyester plastics. Recent researches on PET hydrolases have shown great potential of enzymatic degradation and recycling of plastics. Meanwhile, the biodegradation pathway of PET has become a reference model for the biodegradation of other plastics. This review summarizes the sources of PET hydrolases and their degradation capacity, degradation mechanism of PET by the most representative PET hydrolase-IsPETase, and recently reported highly efficient degrading enzymes through enzyme engineering. The advances of PET hydrolases may facilitate the research on the degradation mechanism of PET and further exploration and engineering of efficient PET degradation enzymes.

The degradation of plastics and the production of polyhydroxyalkanoates (PHA) / 生物工程学报

In recent years, the petroleum-based plastic pollution problem has been causing global attention. The idea of "degradation and up-cycling of plastics" was proposed for solving the environmental pollution caused by non-degradable plastics. Following this idea, plastics would be firstly degraded and then reconstructed. Polyhydroxyalkanoates (PHA) can be produced from the degraded plastic monomers as a choice to recycle among various plastics. PHA, a family of biopolyesters synthesized by many microbes, have attracted great interest in industrial, agricultural and medical sectors due to its biodegradability, biocompatibility, thermoplasticity and carbon neutrality. Moreover, the regulations on PHA monomer compositions, processing technology, and modification methods may further improve the material properties, making PHA a promising alternative to traditional plastics. Furthermore, the application of the "next-generation industrial biotechnology (NGIB)" utilizing extremophiles for PHA production is expected to enhance the PHA market competitiveness, promoting this environmentally friendly bio-based material to partially replace petroleum-based products, and achieve sustainable development with carbon-neutrality. This review summarizes the basic material properties, plastic upcycling via PHA biosynthesis, processing and modification methods of PHA, and biosynthesis of novel PHA.

SIRT1 activation synergizes with FXR agonism in hepatoprotection via governing nucleocytoplasmic shuttling and degradation of FXR

Farnesoid X receptor (FXR) is widely accepted as a promising target for various liver diseases; however, panels of ligands in drug development show limited clinical benefits, without a clear mechanism. Here, we reveal that acetylation initiates and orchestrates FXR nucleocytoplasmic shuttling and then enhances degradation by the cytosolic E3 ligase CHIP under conditions of liver injury, which represents the major culprit that limits the clinical benefits of FXR agonists against liver diseases. Upon inflammatory and apoptotic stimulation, enhanced FXR acetylation at K217, closed to the nuclear location signal, blocks its recognition by importin KPNA3, thereby preventing its nuclear import. Concomitantly, reduced phosphorylation at T442 within the nuclear export signals promotes its recognition by exportin CRM1, and thereby facilitating FXR export to the cytosol. Acetylation governs nucleocytoplasmic shuttling of FXR, resulting in enhanced cytosolic retention of FXR that is amenable to degradation by CHIP. SIRT1 activators reduce FXR acetylation and prevent its cytosolic degradation. More importantly, SIRT1 activators synergize with FXR agonists in combating acute and chronic liver injuries. In conclusion, these findings innovate a promising strategy to develop therapeutics against liver diseases by combining SIRT1 activators and FXR agonists.

Nanopolyphenol rejuvenates microglial surveillance of multiple misfolded proteins through metabolic reprogramming

Microglial surveillance plays an essential role in clearing misfolded proteins such as amyloid-beta, tau, and α-synuclein aggregates in neurodegenerative diseases. However, due to the complex structure and ambiguous pathogenic species of the misfolded proteins, a universal approach to remove the misfolded proteins remains unavailable. Here, we found that a polyphenol, α-mangostin, reprogrammed metabolism in the disease-associated microglia through shifting glycolysis to oxidative phosphorylation, which holistically rejuvenated microglial surveillance capacity to enhance microglial phagocytosis and autophagy-mediated degradation of multiple misfolded proteins. Nanoformulation of α-mangostin efficiently delivered α-mangostin to microglia, relieved the reactive status and rejuvenated the misfolded-proteins clearance capacity of microglia, which thus impressively relieved the neuropathological changes in both Alzheimer's disease and Parkinson's disease model mice. These findings provide direct evidences for the concept of rejuvenating microglial surveillance of multiple misfolded proteins through metabolic reprogramming, and demonstrate nanoformulated α-mangostin as a potential and universal therapy against neurodegenerative diseases.