ObjectiveRecent successful restoration of the native conformation and function of the complementary-determining regions (CDRs) of antibodies on gold nanoparticles (AuNPs) demonstrates that the era of molecular conformational engineering is dawning. Basically, molecular conformational engineering aims to precisely tune flexible non-functional molecules into special conformations to carry out novel functions, in the same way as protein folding. In order to explore the general applicability of molecular conformational engineering, as well as to reveal the mechanism of protein structure-function relationship, the objective of this work is to restore the native conformation and function of the CDRs of an antibody on platinum nanoparticles (PtNPs). MethodsThe CDR fragment of the anti-lysozyme antibody cAB-lys3, which has no stable conformation or function in free state, was conjugated onto the surface of PtNPs through two Pt-S bonds. The original antigen-recognizing function of the CDR restored on PtNPs was assessed by the specific inhibition of the enzymatic activity of lysozyme by the PtNP-CDR conjugates. ResultsAfter optimization of the peptide density on the surface of PtNPs and modification of PtNPs with polyethylene glycol (PEG), the resulted PtNP-based hybrid artificial antibody (PtNP-10PEG-30P1), dubbed Platinumbody, could bind specifically to lysozyme and significantly inhibit the activity of lysozyme. ConclusionThis is the first time that the fragment of a protein could refold on PtNPs. Together with the previous Goldbody and Silverbody, current work demonstrates that artificial proteins could be generally created by restoration of the native conformation of natural proteins fragments on NPs.

Background/Aims: Despite the high efficacy of direct-acting antivirals (DAAs), approximately 1–3% of hepatitis C virus (HCV) patients fail to achieve a sustained virological response. We conducted a nationwide study to investigate risk factors associated with DAA treatment failure. Machine-learning algorithms have been applied to discriminate subjects who may fail to respond to DAA therapy. Methods: We analyzed the Taiwan HCV Registry Program database to explore predictors of DAA failure in HCV patients. Fifty-five host and virological features were assessed using multivariate logistic regression, decision tree, random forest, eXtreme Gradient Boosting (XGBoost), and artificial neural network. The primary outcome was undetectable HCV RNA at 12 weeks after the end of treatment. Results: The training (n=23,955) and validation (n=10,346) datasets had similar baseline demographics, with an overall DAA failure rate of 1.6% (n=538). Multivariate logistic regression analysis revealed that liver cirrhosis, hepatocellular carcinoma, poor DAA adherence, and higher hemoglobin A1c were significantly associated with virological failure. XGBoost outperformed the other algorithms and logistic regression models, with an area under the receiver operating characteristic curve of 1.000 in the training dataset and 0.803 in the validation dataset. The top five predictors of treatment failure were HCV RNA, body mass index, α-fetoprotein, platelets, and FIB-4 index. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the XGBoost model (cutoff value=0.5) were 99.5%, 69.7%, 99.9%, 97.4%, and 99.5%, respectively, for the entire dataset. Conclusions Machine learning algorithms effectively provide risk stratification for DAA failure and additional information on the factors associated with DAA failure.

Background and Objectives: Quantitative flow ratio (QFR) is an angiography-based technique for functional assessment of coronary artery stenosis. This study investigated the response of QFR to different degree of stenosis severity and its ability to predict the positron emission tomography (PET)-defined myocardial ischemia. Methods: From 109 patients with 185 vessels who underwent both 13 N-ammonia PET and invasive physiological measurement, we compared QFR, fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) for the responses to the different degree of anatomical (percent diameter stenosis [%DS]) and hemodynamic (relative flow reserve [RFR], coronary flow reserve, hyperemic stenosis resistance, and stress myocardial flow) stenosis severity and diagnostic performance against PET-derived parameters. Results: QFR, FFR, and iFR showed similar responses to both anatomic and hemodynamic stenosis severity. Regarding RFR, the diagnostic accuracy of QFR was lower than FFR (76.2% vs. 83.2%, p=0.021) and iFR (76.2% vs. 84.3%, p=0.031). For coronary flow capacity (CFC), QFR showed a lower accuracy than iFR (74.1% vs. 82%, p=0.031) and lower discriminant function than FFR (area under curve: 0.74 vs. 0.79, p=0.044). Discordance between QFR and FFR or iFR was shown in 14.6% of cases and was driven by the difference in %DS and heterogeneous distribution of PET-derived RFR and stress myocardial blood flow. Conclusions QFR demonstrated a similar response to different anatomic and hemodynamic stenosis severity as FFR or iFR. However, its diagnostic performance was inferior to FFR and iFR when PET-derived RFR and CFC were used as a reference.

Background and Objectives: Quantitative flow ratio (QFR) is an angiography-based technique for functional assessment of coronary artery stenosis. This study investigated the response of QFR to different degree of stenosis severity and its ability to predict the positron emission tomography (PET)-defined myocardial ischemia. Methods: From 109 patients with 185 vessels who underwent both 13 N-ammonia PET and invasive physiological measurement, we compared QFR, fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) for the responses to the different degree of anatomical (percent diameter stenosis [%DS]) and hemodynamic (relative flow reserve [RFR], coronary flow reserve, hyperemic stenosis resistance, and stress myocardial flow) stenosis severity and diagnostic performance against PET-derived parameters. Results: QFR, FFR, and iFR showed similar responses to both anatomic and hemodynamic stenosis severity. Regarding RFR, the diagnostic accuracy of QFR was lower than FFR (76.2% vs. 83.2%, p=0.021) and iFR (76.2% vs. 84.3%, p=0.031). For coronary flow capacity (CFC), QFR showed a lower accuracy than iFR (74.1% vs. 82%, p=0.031) and lower discriminant function than FFR (area under curve: 0.74 vs. 0.79, p=0.044). Discordance between QFR and FFR or iFR was shown in 14.6% of cases and was driven by the difference in %DS and heterogeneous distribution of PET-derived RFR and stress myocardial blood flow. Conclusions QFR demonstrated a similar response to different anatomic and hemodynamic stenosis severity as FFR or iFR. However, its diagnostic performance was inferior to FFR and iFR when PET-derived RFR and CFC were used as a reference.

OBJECTIVES: To evaluate residents' knowledge, attitude and behavior towards coronavirus disease 2019 (COVID-19) in Hunan Province, and to explore the factors influencing behaviors. METHODS: A self-designed questionnaire was used to conduct an online survey for 4 139 Hunan residents. The contents included general population information, residents' knowledge, attitude and practice to COVID-19. RESULTS: Mean scores of knowledge, attitude, and behavior were 29.82±3.16, 6.71±1.12, and 14.93±1.45, respectively. Residents had the highest score of major symptoms of COVID-19 (3.96±0.39), but the lowest was the main transmission routes (3.47±0.89). A total of 22.68% of the residents were very or relatively afraid of the outbreak, but 95.22% of the residents had confidence in defeating COVID-19. In behavior dimension, "handling of suspicious symptoms" had the lowest score (3.58±0.75). The behavior implementation rate of "keep the surfaces of household items clean" (80.50%), "doing more exercise, reasonable diet, working and resting regularly" (84.59%), and "avoid hand contacting with eyes, mouth or nose" (89.51%) were relatively low. Pearson correlation coefficient showed that the knowledge, attitude, and practices score were correlated with each other (knowledge vs behavior: =0.366; knowledge vs attitude: =0.041; attitude vs behavior: =0.100; all <0.05). Multiple linear regression analysis showed that the knowledge, attitude and behavior on COVID-19 were mostly influenced by education background (all <0.05), and the independent factors affecting behavior included knowledge and attitude, gender, permanent residence, education background (all <0.05). CONCLUSIONS Residents in Hunan Province have a good knowledge, attitude, and behavior to COVID-19. Nevertheless there are still weak links to be improved in all dimensions. It is necessary to strengthen knowledge and behavior of family protection, and care for residents' psychological health, especially persons with low education degree, male and rural residents.
Betacoronavirus ; China ; Coronavirus Infections ; psychology ; Health Knowledge, Attitudes, Practice ; Humans ; Pandemics ; Pneumonia, Viral ; psychology ; Surveys and Questionnaires

Fourteen compounds were isolated from the ethanol extract of Dalbergiae Odoriferae Lignum by various chromatographic techniques, including column chromatographies on silica gel, Sephadex LH-20 and semi-preparative HPLC. Their structures were determined by spectroscopic techniques as S-3'-hydroxy-7,2',4'-trimethoxyisoxane(1), 2-(2',4'-dimethoxyphenyl)-6-hydroxybenzofuran(2), 2-(2'-hydroxy-4'-methoxyphenyl)-6-methoxybenzofuran(3), 7,2',4'-trimethoxydihydroisoflavone(4), sativanone(5), 3,9-dimethoxy-6H-benzofuro[3,2-c]chromen-6-one(6),(6 aS,11 aS)-homopterocarpin(7),(6 aS,11 aS)-8-hydroxy-3,9-dimethoxypterocarpan(8),(6 aS,11 aS)-3,8,9-trimethoxypterocarpan(9), isodalbergin(10), isoliquiritigenin(11), butein(12), butin(13) and 3,7,4'-trihydroxyflavone(14). Among them, compound 1 was a new compound, while 2 and 3 were new natural products, 6, 8, 9 and 14 were isolated for the first time from Dalbergiae Odoriferae Lignum. Compounds 1-14 were tested for their cytotoxic activity against human hepatoma cell line BEL-7402, human gastric cancer cell line SCG-7901, human lung cancer cell line A549, human chronic myeloid leukemia cell line K562 and HeLa human cervical cancer cellline by MTT method. Compound 1 exhibited significant cytotoxicity with IC_(50) values ranging from 2.85 to 11.62 μg·mL~(-1). In addition, 2, 11 and 12 showed weak cytotoxic activities.
Antineoplastic Agents ; Chromatography, High Pressure Liquid ; HeLa Cells ; Humans

Atropa belladonna seedlings were used as experimental materials and cultivated by soil culture method. Different concentrations(0,0.05,0.1,0.2,0.5 mmol·L~(-1))of NO donor sodium nitroprusside(SNP) were sprayed on the leaves. The effects of different concentrations of SNP and different treatment time(4,8,12,16 d) on nitrogen metabolism, secondary metabolite content, precursor content of tropane alkaloid synthesis pathway and expression of key enzyme genes under 100 mmol·L~(-1) NaCl stress were studied. The results showed that with the prolongation of salt stress, the nitrogen metabolism and the accumulation of secondary metabolites of A. belladonna were inhibited to some extent. After treatment with different concentrations of exogenous SNP, the ammonium nitrogen content decreased dramatically, and the contents of nitrate nitrogen, free amino acid, soluble protein and the activities of key enzymes of nitrogen metabolism(NR, GS, GDH) were all greatly improved; the contents of precursor amino acids(ornithine, arginine) and polyamines(Put, Spd, Spm) in the secondary metabolic pathway have increased to varying degrees. The qRT-PCR analysis showed that exogenous SNP treatment can effectively promote the high expression of key enzyme genes PMT, TRⅠ and H6H in the secondary metabolic pathway of A. belladonna, and the production of hyoscyamine and scopolamine were increased notably. In summary, the application of appropriate concentration of SNP can effectively alleviate the inhibition of salt stress on the nitrogen metabolism and secondary metabolism of Atropa belladonna, and enhance its salt tolerance. Overall, 0.1 mmol·L~(-1) and 0.2 mmol·L~(-1) SNP treatment achieved the most remarkable effect.
Atropa belladonna/metabolism* ; Hyoscyamine/analysis* ; Nitrogen/metabolism* ; Nitroprusside ; Scopolamine/analysis* ; Secondary Metabolism ; Sodium Chloride ; Stress, Physiological

According to the data of Pinellia ternate transcriptome,two calmodulin genes were cloned and named as Pt Ca M1 and PtCa M2 respectively. The results of bioinformatics analysis showed that Pt Ca Ms genes contained a 450 bp open reading frame,encoding149 amino acids.The identity of the coding sequences was 80%,and the identity of amino acids sequence was 91%. Pt Ca Ms genes contained EF-hand structure domain,belonging to the Ca M families. The Real-time PCR analysed the expression patterns of Pt Ca Ms in different tissues and different treatments. RESULTS:: showed that Pt Ca M1 and Pt Ca M2 gene were the highest expression level in tuber. Under Ca Cl2 treatment,the expressions of Pt Ca Ms were significantly higher than the control. Under EGTA,La Cl3 and TFP treatments,the expression level of Pt Ca Ms decreased gradually. In this study,the Pt Ca Ms gene were successfully cloned from P. ternate,which laid a foundation for the functional characteristic of Pt Ca Ms gene and the synthesis of alkaloids from P. ternata for further study.
Calmodulin ; genetics ; Cloning, Molecular ; Genes, Plant ; Pinellia ; genetics ; Plant Tubers ; genetics

OBJECTIVETo evaluate the long-term survival of multidisciplinary treatment based on thoracic surgery for cervical esophageal squamous cell carcinoma.

METHODSThe clinical characters and follow-up data of forty-one cervical esophageal cancer patients who accepted multidisciplinary treatment based on surgery with preservation of pharynx and larynx were retrospectively reviewed, and the long-term survival was compared with 480 non-cervical esophageal cancers who accepted surgery in the same period done by the same surgical team.

RESULTSThere were 28 males and 13 females with a mean age of 62 years old. In the cervical esophageal cancer group, 30 patients accepted neoadjuvant chemotherapy, 25 patients accepted adjuvant chemotherapy, and 21 patients accepted both. Six patients received postoperative radiation. Four patients underwent exploratory surgery alone, and 37 cases underwent radical surgery and cervical anastomosis. One case died during the perioperative period. The 1-, 3-, 5- and 8-year survival rates were 96.8%, 52.6%, 35.1%, and 35.1% in the 36 patients with cervical esophageal cancer who underwent radical surgery, and were 85.0%, 54.3%, 45.0%, and 36.7% respectively in the 457 non-cervical esophageal cancer patients. There was no significant difference between the cervical group and non-cervical group(P=0.91).

CONCLUSIONCervical esophageal cancer should be treated in a multidisciplinary approach to obtain satisfactory long-term outcomes.

Combined Modality Therapy ; Esophageal Neoplasms ; surgery ; Esophagectomy ; methods ; Female ; Follow-Up Studies ; Humans ; Larynx ; surgery ; Male ; Middle Aged ; Pharynx ; surgery ; Retrospective Studies ; Treatment Outcome

OBJECTIVETo assess the impact of early enteral nutrition (EN) on the intestinal motility of patients after esophagectomy.

METHODSThirty-five consecutive patients undergoing esophagectomy for esophageal cancer by a single surgical team from the Peking University Cancer Hospital from June 2011 to July 2011 were enrolled. Patients were randomly divided into EN group (n=20) and parenteral nutrition group (control group, n=15) within 24 h after esophagectomy procedure. Bowel sound recovery time was monitored by auscultation, and the gastrointestinal tract symptoms were recorded.

RESULTSBowel sound recovery time was (45.1±20.3) h in the EN group, and was (56.7±17.0) h in the control group (P=0.082). Gastrointestinal symptoms such as nausea, abdominal distension, diarrhea occurred in 4 patients in EN group and 3 patients in control group and were alleviated by lowering infusion speed and more off-bed ambulation, and no significant difference was seen between the two groups (P=1.000).

CONCLUSIONSEarly enteral nutrition in the patients after esophagectomy is safe and feasible. Early enteral nutrition does not delayed bowel function recovery or increase gastrointestinal symptoms.

Aged ; Enteral Nutrition ; Esophageal Neoplasms ; physiopathology ; therapy ; Female ; Gastrointestinal Motility ; physiology ; Humans ; Male ; Middle Aged ; Postoperative Care ; Prospective Studies