Metabolic differences in MSTN and FGF5 dual-gene edited sheep muscle cells during myogenesis.

Dynamic metabolic reprogramming occurs at different stages of myogenesis and contributes to the fate determination of skeletal muscle satellite cells (MuSCs). Accumulating evidence suggests that mutations in myostatin (MSTN) have a vital role in regulating muscle energy metabolism. Here, we explored the metabolic reprogramming in MuSCs and myotube cells in MSTN and FGF5 dual-gene edited sheep models prepared previously, and also focused on the metabolic alterations during myogenic differentiation of MuSCs. Our study revealed that the pathways of nucleotide metabolism, pantothenate and CoA biosynthesis were weakened, while the unsaturated fatty acids biosynthesis were strengthened during myogenic differentiation of sheep MuSCs. The MSTN and FGF5 dual-gene editing mainly inhibited nucleotide metabolism and biosynthesis of unsaturated fatty acids in sheep MuSCs, reduced the number of lipid droplets in per satellite cell, and promoted the pentose phosphate pathway, and the interconversion of pentose and glucuronate. The MSTN and FGF5 dual-gene editing also resulted in the inhibition of nucleotide metabolism and TCA cycle pathway in differentiated myotube cells. The differential metabolites we identified can be characterized as biomarkers of different cellular states, and providing a new reference for MSTN and FGF5 dual-gene editing in regulation of muscle development. It may also provide a reference for the development of muscle regeneration drugs targeting biomarkers.

Genotype and Phenotype Characteristics of 58 Cases of Mitochondrial Epilepsy with Nuclear DNA Mutations in Children.

OBJECTIVE: Identify the genotype and clinical characteristics of mitochondrial epilepsy caused by nDNA mutations in Chinese children and explore the treatment and prognosis of the condition. STUDY DESIGN: This is a retrospective cohort study conducted at a single center, including patients diagnosed with an established nDNA mutation-associated primary mitochondrial disease between October 2012 and March 2023 who also met the practical clinical definition of epilepsy published by the ILAE in 2014. RESULTS: Of the 58 patients identified, 74.1% had an onset before the age of 1 year and 63.8% had seizures as their initial symptom. Developmental and epileptic encephalopathy (DEE) (31%) are the most common phenotypes. The most frequently observed MRI abnormalities include abnormal signal asymmetry in the bilateral basal ganglia and/or brainstem (34.7%), as well as brain atrophy, myelin sheath dysplasia, and corpus callosum dysplasia (32.7%). Of the 40 patients followed, seizure treatment was effective in 18 of the cases, while it was ineffective in 22. The mitochondrial DNA depletion syndrome (MDS) was found to be more difficult to control seizures than other phenotypes (P < 0.05). Additionally, the MDS was associated with a significantly higher mortality rate compared to alternative phenotypes (P < 0.05). CONCLUSIONS: The onset of mitochondrial epilepsy due to nDNA mutations is early and seizures are the most common initial symptom. DEE is the most common phenotype. Characteristic MRI abnormalities in the brain may be helpful in the diagnosis of primary mitochondrial disease. People with MDS typically face challenges in seizure control and have a poor prognosis.

Leigh Syndrome: A Study of 209 Patients at the Beijing Children's Hospital.

OBJECTIVE: Leigh syndrome (LS) is a heterogeneous neurodegenerative disease and the most frequent pediatric manifestation of mitochondrial disease. In the largest patient collection to date, this study aimed to provide new insights into the clinical and genetic spectrum of LS, defect-specific associations, and predictors of disease course and survival. METHODS: Clinical, metabolic, neuroimaging, onset, and survival data were collected from the medical records of 209 patients referred to the Beijing Children's Hospital with symmetrical basal ganglia and/or brainstem neuroimaging changes indicative of LS by 30 centers from the Chinese network of mitochondrial disease (mitoC-NET) between January 2013 and July 2021 for exploratory analysis. RESULTS: Pathogenic variants were identified in 52 genes, most frequently MT-ATP6, SURF1, and PDHA1. Maternally inherited variants accounted for 42% (heteroplasmy level ≥90% in 64%). Phenotypes spanned 92 Human Phenotype Ontology terms. Elevated serum lactate (144/195), global developmental delay (142/209), and developmental regression (103/209) were most frequent. Discriminating neuroimaging and/or clinical features were identified for MT-ATP6 (m.9176T>C), MT-ND5, PDHA1, SUCLG1, and SURF1. Poorest survival was associated with MT-ND5, MT-ATP6 (m.8993T>C and m.9176T>C), SURF1, and ALDH5A1 (≤50% 3 year's survival), in contrast to milder defects with specific treatment (ECHS1 and SLC19A3, 100% 3 year's survival). INTERPRETATION: Our data define phenotype, onset, and survival of LS in a defect-specific manner, identifying features discriminating between genetic defects and predictive of disease outcome. These findings are essential to early diagnosis, in optimizing family counseling, and to the design and monitoring of future clinical trials, the next frontier of LS research. ANN NEUROL 2022;91:466-482.

Whole genome and exome sequencing identify NDUFV2 mutations as a new cause of progressive cavitating leukoencephalopathy.

BACKGROUND: Progressive cavitating leukoencephalopathy (PCL) is thought to result from mutations in nuclear genes affecting mitochondrial function and energy metabolism. To date, mutations in two subunits of complex I, NDUFS1 and NDUFV1, have been reported to be related to PCL. METHODS: Patients underwent clinical examinations, brain MRI, skin biopsy and muscle biopsy. Whole-genome or whole-exome sequencing was performed on the index patients from two unrelated families with PCL. The effects of the mutations were examined through complementation of the NDUFV2 mutation by cDNA expression. RESULTS: The common clinical features of the patients in this study were recurring episodes of acute or subacute developmental regression that appeared in the first years of life, followed by gradual remissions and prolonged periods of stability. MRI showed leukoencephalopathy with multiple cavities. Three novel NDUFV2 missense mutations were identified in these families. Complex I deficiency was confirmed in affected individuals' fibroblasts and a muscle biopsy. Functional and structural analyses revealed that these mutations affect the structural stability and function of the NDUFV2 protein, indicating that defective NDUFV2 function is responsible for the phenotypes in these individuals. CONCLUSIONS: Here, we report the clinical presentations, neuroimaging and molecular and functional analyses of novel mutations in NDUFV2 in two sibling pairs of two Chinese families presenting with PCL. We hereby expand the knowledge on the clinical phenotypes associated with mutations in NDUFV2 and the genotypes causative for PCL.

Identification and characterization of novel MPC1 gene variants causing mitochondrial pyruvate carrier deficiency.

Pyruvate, the end product of glycolysis, is a key metabolic molecule enabling mitochondrial adenosine triphosphate synthesis and takes part in multiple biosynthetic pathways within mitochondria. The mitochondrial pyruvate carrier (MPC) plays a vital role in transporting pyruvate from the cytosol into the organelle. In humans, MPC is a hetero-oligomeric complex formed by the MPC1 and MPC2 paralogs that are both necessary to stabilize each other and form a functional MPC. MPC deficiency (OMIM#614741) due to pathogenic MPC1 variants is a rare autosomal recessive disease involving developmental delay, microcephaly, growth failure, and increased serum lactate and pyruvate. To date, two MPC1 variants in four cases have been reported, though only one with a detailed clinical description. Herein, we report three novel pathogenic MPC1 variants in six patients from three unrelated families, identified within European, Kuwaiti, and Chinese mitochondrial disease patient cohorts, one of whom presented as a Leigh-like syndrome. Functional analysis in primary fibroblasts from the patients revealed decreased expression of MPC1 and MPC2. We rescued pyruvate-driven oxygen consumption rate in patient's fibroblasts by reconstituting with wild-type MPC1. Complementing homozygous MPC1 mutant cDNA with CRISPR-deleted MPC1 C2C12 cells verified the mechanism of variants: unstable MPC complex or ablated pyruvate uptake activity. Furthermore, we showed that glutamine and beta-hydroxybutyrate were alternative substrates to maintain mitochondrial respiration when cells lack pyruvate. In conclusion, we expand the clinical phenotypes and genotypes associated with MPC deficiency, with our studies revealing glutamine as a potential therapy for MPC deficiency.

MicroRNA-454 modulates the oxidative stress and neuronal apoptosis after cerebral ischemia/reperfusion injury via targeting NADPH oxidase 4 (NOX4).

To investigate the function of miR-454 in ischemic stroke, this study was carried out. Cerebral ischemia/reperfusion (I/R) injury animal model and a SHSY5Y cell culture model of oxygen-glucose deprivation/reoxygenation (OGD/R) were constructed. The effects of miR-454 were detected by evaluating the levels of biochemical markers, gene expression, and pathophysiological markers. The results showed that NOX4 level was elevated, while miR-454 expression was reduced in I/R brain samples and in OGD/R-treated cells. The miR-454 agomir declined NOX4 level and reactive oxygen species (ROS) production in rats suffering from I/R. Furthermore, microRNA-145 (miR-454) overexpression inhibited NOX4 level and ROS production in cells treated by OGD/R and decreased luciferase activity in cells transfected with NOX4-wild type (WT) reporter plasmid. Meanwhile, our results proved that the protected effects of miR-454 on SH-SY5Y cells treated by OGD/R were reversed by pcDNA-NOX4 transfection. MiR-454 protected animals from brain injury induced by cerebral I/R via directly regulating its target gene NOX4, illustrating a curatively potential target for treating ischemic stroke.

Novel ECHS1 mutations in Leigh syndrome identified by whole-exome sequencing in five Chinese families: case report.

BACKGROUND: Short-chain enoyl-CoA hydratase deficiency (ECHS1D), also known as ECHS1 deficiency, is a rare inborn metabolic disorder with clinical presentations characterized by Leigh syndrome (LS). Thirty-four different pathogenic mutations have been identified from over 40 patients to date. CASE PRESENTATION: Here, we report five Chinese patients with clinical syndromes typified as LS. Despite different initial symptoms, all patients presented developmental regression, dystonia, common radiological features such as symmetrical bilateral brain abnormalities, and similar metabolic results such as elevated plasma lactate and 2,3-dihydroxy-2-methylbutyrate. Utilizing whole-exome sequencing (WES), we identified eight distinct variants in ECHS1, with six novel variants, and the remaining two variants have been previously reported. Interestingly, one of the six novel variants, c.463G > A (p.Gly155Ser), was detected in three patients from unrelated families, suggesting a potential founder effect already described for a few mutations in LS. Incorporating both genetic analysis and medical results, including magnetic resonance imaging (MRI), electroencephalography (EEG), and biochemical testing, our study enriched the mutation spectrum of the ECHS1 gene and confirmed the phenotypic presentations of LS. CONCLUSIONS: The severity of ECHS1 deficiency seems to vary. It was affected by both genetics and external environmental factors that lead to increased metabolism. Our study enriched the mutation spectrum of the ECHS1 gene, confirmed the phenotypic presentations, and highlighted the importance of the valine catabolic pathway in Leigh syndrome. Further studies are required to examine the potential founder mutation c.463G > A (p.Gly155Ser) and the role of ECHS1 in relevant pathways.

eRAM: encyclopedia of rare disease annotations for precision medicine.

Rare diseases affect over a hundred million people worldwide, most of these patients are not accurately diagnosed and effectively treated. The limited knowledge of rare diseases forms the biggest obstacle for improving their treatment. Detailed clinical phenotyping is considered as a keystone of deciphering genes and realizing the precision medicine for rare diseases. Here, we preset a standardized system for various types of rare diseases, called encyclopedia of Rare disease Annotations for Precision Medicine (eRAM). eRAM was built by text-mining nearly 10 million scientific publications and electronic medical records, and integrating various data in existing recognized databases (such as Unified Medical Language System (UMLS), Human Phenotype Ontology, Orphanet, OMIM, GWAS). eRAM systematically incorporates currently available data on clinical manifestations and molecular mechanisms of rare diseases and uncovers many novel associations among diseases. eRAM provides enriched annotations for 15 942 rare diseases, yielding 6147 human disease related phenotype terms, 31 661 mammalians phenotype terms, 10,202 symptoms from UMLS, 18 815 genes and 92 580 genotypes. eRAM can not only provide information about rare disease mechanism but also facilitate clinicians to make accurate diagnostic and therapeutic decisions towards rare diseases. eRAM can be freely accessed at http://www.unimd.org/eram/.

PedAM: a database for Pediatric Disease Annotation and Medicine.

There is a significant number of children around the world suffering from the consequence of the misdiagnosis and ineffective treatment for various diseases. To facilitate the precision medicine in pediatrics, a database namely the Pediatric Disease Annotations & Medicines (PedAM) has been built to standardize and classify pediatric diseases. The PedAM integrates both biomedical resources and clinical data from Electronic Medical Records to support the development of computational tools, by which enables robust data analysis and integration. It also uses disease-manifestation (D-M) integrated from existing biomedical ontologies as prior knowledge to automatically recognize text-mined, D-M-specific syntactic patterns from 774 514 full-text articles and 8 848 796 abstracts in MEDLINE. Additionally, disease connections based on phenotypes or genes can be visualized on the web page of PedAM. Currently, the PedAM contains standardized 8528 pediatric disease terms (4542 unique disease concepts and 3986 synonyms) with eight annotation fields for each disease, including definition synonyms, gene, symptom, cross-reference (Xref), human phenotypes and its corresponding phenotypes in the mouse. The database PedAM is freely accessible at http://www.unimd.org/pedam/.

Shiga Toxin Type 1a (Stx1a) Reduces the Toxicity of the More Potent Stx2a In Vivo and In Vitro.

Shiga toxin (Stx)-producing Escherichia coli (STEC) causes foodborne outbreaks of bloody diarrhea. There are two major types of immunologically distinct Stxs: Stx1a and Stx2a. Stx1a is more cytotoxic to Vero cells than Stx2a, but Stx2a has a lower 50% lethal dose (LD50) in mice. Epidemiological data suggest that infections by STEC strains that produce only Stx2a progress more often to a life-threatening sequela of infection called hemolytic-uremic syndrome (HUS) than isolates that make Stx1a only or produce both Stx1a and Stx2a. In this study, we found that an E. coli O26:H11 strain that produces both Stx1a and Stx2a was virulent in streptomycin- and ciprofloxacin-treated mice and that mice were protected by administration of an anti-Stx2 antibody. However, we discovered that in the absence of ciprofloxacin, neutralization of Stx1a enhanced the virulence of the strain, a result that corroborated our previous finding that Stx1a reduces the toxicity of Stx2a by the oral route. We further found that intraperitoneal administration of the purified Stx1a B subunit delayed the mean time to death of mice intoxicated with Stx2a and reduced the cytotoxic effect of Stx2a on Vero cells. Taken together, our data suggest that Stx1a reduces both the pathogenicity of Stx2 in vivo and cytotoxicity in vitro.

Recent topics: the diagnosis, molecular genesis, and treatment of mitochondrial diseases.

Mitochondrial diseases are inherited metabolic diseases based on disorders of energy production. The expansion of exome analyses has led to the discovery of many pathogenic nuclear genes associated with these diseases, and research into the pathogenesis of metabolic diseases has progressed. In cases of Leigh syndrome, it is desirable to perform both biochemical and genetic analyses, and pathogenic gene mutations have been identified in over half of the cases analyzed this way. Tandem mass screening and organic acid analyses of urine can sometimes provide important information that leads to the identification of pathogenic genes. Our comprehensive gene analyses have led to the discovery of several novel genes for mitochondrial diseases. Indeed, we reported that GTPBP3 and QRSL1 are involved in mitochondrial DNA maturation. In 2017, as a result of international collaboration, we also identified that mutations in ATAD3 and C1QBP cause mitochondrial disease. Given the varied pathogeneses, treatments for mitochondrial diseases should be specifically tailored to the mutated gene. Clinical trials of sodium pyruvate, 5-aminolevulinic acid with sodium ferrous citrate, and taurine as a treatment for mitochondrial disease have begun in Japan. Given that some mitochondrial diseases may respond well to certain treatments if the pathogenic gene can be identified, an early genetic diagnosis is crucial. Additionally, in Japan, prenatal diagnoses for mitochondrial diseases caused by nuclear genes have been achieved for genes shown to be pathogenic. Treatment and management approaches, including prenatal diagnoses, specifically tailored to the various phenotypes and pathologies of mitochondrial diseases are expected to become increasingly available.

Dynamics analysis of epidemic and information spreading in overlay networks.

We establish an SIS-UAU model to present the dynamics of epidemic and information spreading in overlay networks. The overlay network is represented by two layers: one where the dynamics of the epidemic evolves and another where the information spreads. We theoretically derive the explicit formulas for the basic reproduction number of awareness R0a by analyzing the self-consistent equation and the basic reproduction number of disease R0d by using the next generation matrix. The formula of R0d shows that the effect of awareness can reduce the basic reproduction number of disease. In particular, when awareness does not affect epidemic spreading, R0d is shown to match the existing theoretical results. Furthermore, we demonstrate that the disease-free equilibrium is globally asymptotically stable if R0d<1; and the endemic equilibrium is globally asymptotically stable if R0d>1. Finally, numerical simulations show that information plays a vital role in preventing and controlling disease and effectively reduces the final disease scale.

Patterns of care among patients receiving sequential targeted therapies for advanced renal cell carcinoma: A retrospective chart review in the USA.

OBJECTIVES: To assess real-world treatment patterns of targeted therapies after failure of first-line tyrosine kinase inhibitors in patients with advanced renal cell carcinoma. METHODS: A large, retrospective review of medical charts of patients with advanced renal cell carcinoma in the USA was carried out. Descriptive statistics were used to summarize physicians' and patients' characteristics, treatment sequences, and reasons for treatment choices. P-values were calculated using χ2 -tests for categorical variables and Wilcoxon rank-sum tests for continuous variables. A descriptive comparison was carried out between current results and those of a previous treatment pattern study conducted in 2012 to identify changes in treatment patterns over time. RESULTS: Sunitinib and everolimus remained the most commonly-used first and second targeted therapies, respectively. Among patients who continued to a third targeted therapy, everolimus and axitinib were the most commonly-used treatments after second targeted therapy with a tyrosine kinase inhibitor and a mammalian target of rapamycin inhibitor, respectively. The use of pazopanib as first targeted therapy, and of axitinib and sorafenib as second targeted therapies, increased over time. Efficacy, treatment guidelines and a different mechanism of action were the main reasons given by physicians for choosing among second targeted therapies after failure of a first tyrosine kinase inhibitor. CONCLUSIONS: The results of the present study document patterns of care during a period of rapid and ongoing therapeutic advancement in advanced renal cell carcinoma. Sequencing of therapies warrants ongoing analysis in light of new agents entering the advanced renal cell carcinoma treatment landscape.

Establishment of an iPSC line (BCHNDi001-A) from a patient with nicotinamide nucleotide repair system deficiency caused by biallelic NAXD mutations.

NAD(P)HX dehydratase (NAXD) gene is one of the key enzymes encoding the nicotinamide nucleotide repair system, reportedly associated with Encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy, 2 (PEBEL2). Here, we generated an induced pluripotent stem cell (iPSC) line from the dermal fibroblasts (HDFs) of a PEBEL2 patient who carried biallelic mutations, c.101_102delTA(p.Thr35Phefs*63) and c.318C > G (p.Ile160Met) in NAXD. These iPSCs showed stable amplification in vitro, expressed pluripotent markers, and differentiated spontaneously into three germ layers, as well as NAXD mutations with normal karyotype.

Can O-GIcNAc Transferase (OGT) Complex Be Used as a Target for the Treatment of Hematological Malignancies?

The circulatory system is a closed conduit system throughout the body and consists of two parts as follows: the cardiovascular system and the lymphatic system. Hematological malignancies usually grow and multiply in the circulatory system, directly or indirectly affecting its function. These malignancies include multiple myeloma, leukemia, and lymphoma. O-linked ß-N-acetylglucosamine (O-GlcNAc) transferase (OGT) regulates the function and stability of substrate proteins through O-GlcNAc modification. Abnormally expressed OGT is strongly associated with tumorigenesis, including hematological malignancies, colorectal cancer, liver cancer, breast cancer, and prostate cancer. In cells, OGT can assemble with a variety of proteins to form complexes to exercise related biological functions, such as OGT/HCF-1, OGT/TET, NSL, and then regulate glucose metabolism, gene transcription, cell proliferation, and other biological processes, thus affecting the development of hematological malignancies. This review summarizes the complexes involved in the assembly of OGT in cells and the role of related OGT complexes in hematological malignancies. Unraveling the complex network regulated by the OGT complex will facilitate a better understanding of hematologic malignancy development and progression.

Risk of secondary immune thrombocytopenia following alemtuzumab treatment for multiple sclerosis: a systematic review and meta-analysis.

Object: The purpose of this study was to evaluate the risk of secondary immune thrombocytopenia in multiple sclerosis patients treated with alemtuzumab through a meta-analysis. Methods: We searched databases including PubMed, Web of Science, OVID and EMBASE for studies reporting changes in platelet levels in MS patients treated with alemtuzumab from their inception until May 2023 and performed a meta-analysis. Information and data were screened and extracted by two researchers. The inclusion and exclusion criteria were established according to the PICOS principle. The obtained data were analyzed using the R software meta package and the quality assessment was conducted using Newcastle-Ottawa Scale (NOS). The causes of heterogeneity were analyzed using subgroup analysis and sensitivity analysis. Publication bias was evaluated using funnel plots and Egger test. Results: A total of 15 studies were included, encompassing 1,729 multiple sclerosis patients. Meta-analysis of overall secondary ITP in the included studies yielded a pooled rate of 0.0243. The overall incidence of secondary autoimmune events was 0.2589. In addition, subgroup analysis was applied using study regions and study types. The results showed that the incidence rate of secondary ITP in Europe was about 0.0207, while the incidence of autoimmune events (AEs) was 0.2158. The incidence rate of secondary ITP and AEs in North America was significantly higher than in Europe, being 0.0352 and 0.2622. And the analysis showed that the incidence rates of secondary ITP and AEs in prospective studies were 0.0391 and 0.1771. Retrospective studies had an incidence rate of secondary ITP at 2.16, and an incidence rate of AEs at 0.2743. Conclusion: This study found that there was a certain incidence of Immune thrombocytopenia in multiple sclerosis patients after treatment with alemtuzumab. Alemtuzumab may have some interference with platelet levels, and the mechanism may be associated with Treg cells. But due to the absence of a control group in the included literature, we cannot determine the specific impact of Alemtuzumab on platelet levels in patients with MS. Therefore, clinical physicians should perform a comprehensive assessment of the patient's benefit-to-risk ratio before initiating alemtuzumab. Systematic Review Registration: Inplasy website, DOI number is 10.37766/inplasy2024.3.0007.

Increasing GSH-Px Activity and Activating Wnt Pathway Promote Fine Wool Growth in FGF5-Edited Sheep.

Fibroblast growth factor 5 (FGF5) plays key roles in promoting the transition from the anagen to catagen during the hair follicle cycle. The sheep serves as an excellent model for studying hair growth and is frequently utilized in various research processes related to human skin diseases. We used the CRISPR/Cas9 system to generate four FGF5-edited Dorper sheep and only low levels of FGF5 were detected in the edited sheep. The density of fine wool in GE sheep was markedly increased, and the proportion of fine wool with a diameter of 14.4-20.0 µm was significantly higher. The proliferation signal in the skin of gene-edited (GE) sheep was stronger than in wild-type (WT) sheep. FGF5 editing decreased cortisol concentration in the skin, further activated the activity of antioxidant enzymes such as Glutathione peroxidase (GSH-Px), and regulated the expression of Wnt signaling pathways containing Wnt agonists (Rspondins, Rspos) and antagonists (Notum) in hair regeneration. We suggest that FGF5 not only mediates the activation of antioxidant pathways by cortisol, which constitutes a highly coordinated microenvironment in hair follicle cells, but also influences key signals of the Wnt pathway to regulate secondary hair follicle (SHF) development. Overall, our findings here demonstrate that FGF5 plays a significant role in regulating SHF growth in sheep and potentially serves as a molecular marker of fine wool growth in sheep breeding.

A narrative review: narrow-band imaging endoscopic classifications.

Background and Objective: With the development of endoscopic techniques, narrow-band imaging (NBI) has been widely used in the diagnosis of various types of diseases. NBI can detect mucosal lesions at an early stage and different classification strategies have been established to help clinicians in disease diagnosis. However, there is currently no consensus for the classification criteria. This report summarizes the current classifications of diseases using NBI, so as to provide a comprehensive understanding of the various manifestations of mucosal lesions under NBI, and to promote the development of more practical NBI classifications. Methods: The PubMed database was searched for English language articles published between January 1994 and November 2021 using the keywords 'narrow band imaging', 'NBI', and 'classification'. Key Content and Findings: We systematically summarized the NBI classifications and manifestations of different diseases. The morphology of the mucosa and vessels was used as the basis of most classifications. These classifications are mainly helpful to distinguish benign and malignant tumors and to detect early neoplastic lesions. Conclusions: This review summarized existing NBI classifications for different systems. These classifications will be updated as the understanding of diseases increases and new optical techniques become available to better assist doctors in making clinical decisions.

Adsorption and desorption of flavonoids on activated carbon impregnated with different metal ions.

In this study, four metal ions Mg2+, Al3+, Fe3+, and Zn2+ were loaded on the surface of activated carbon by an impregnation method coupled with high-temperature calcination to prepare modified activated carbon. Scanning electron microscopy, specific surface area and pore size analysis, X-ray diffraction, and Fourier infrared spectroscopy were used to evaluate the structure and morphology of the modified activated carbon. The findings show that the modified activated carbon had a large microporous structure and high specific surface area, both of which significantly improved absorbability. This study also investigated the adsorption and desorption kinetics of the prepared activated carbon for three flavonoids with representative structures. The adsorption amounts of quercetin, luteolin, and naringenin in the blank activated carbon reached 920.24 mg g-1, 837.07 mg g-1, and 677.37 mg g-1, while for activated carbon impregnated with Mg, the adsorption amounts reached 976.34 mg g-1, 963.39 mg g-1, and 817.98 mg g-1, respectively; however, the desorption efficiencies of the three flavonoids varied a lot. The differences in desorption rates of naringenin as compared with quercetin and luteolin in the blank activated carbon were 40.13% and 46.22%, respectively, and the difference in desorption rates increased to 78.46% and 86.93% in the activated carbon impregnated with Al. The differences provide a basis for the application of this type of activated carbon in the selective enrichment and separation of flavonoids.