Release of Interface Confined Water Significantly Improves Dentin Bonding.

Water residue and replacement difficulty cause insufficient adhesive infiltration in demineralized dentin matrix (DDM), which produces a defective hybrid layer and thus a bonding durability problem, severely plaguing adhesive dentistry for decades. In this study, we propose that the unique properties of a highly hydrated interface of the porous DDM can give rise to 1 new type of interface, confined liquid water, which accounts for most of the residue water and may be the main cause of insufficient infiltration. To prove our hypothesis, 3 metal ions with increasing binding affinity and complex stability (Na+, Ca2+, and Cu2+) were introduced respectively to coordinate negatively charged groups such as -PO43-, -COO- abundant in the DDM interface. Strong chelation of Ca2+ and Cu2+ rapidly released the confined water, significantly improving penetration of hydrophobic adhesive monomers, while Na+ had little effect. A significant decrease of defects in the hybrid layer and a much decreased modulus gap between the hybrid layer and the adhesive layer greatly optimized the microstructure and micromechanical properties of the tooth-resin bonding interface, thus improving the effectiveness and durability of dentin bonding substantially. This study paves the way for a solution to the core scientific issue of contemporary adhesive dentistry: water residue and replacement in dentin bonding, both theoretically and practically.

[Epidemiology, clinical characteristics and treatment in 278 patients with coronavirus disease 2019 in Guangzhou].

Objective: To retrospective analyze the epidemiology, clinical characteristics, treatment and prognosis in patients with coronavirus disease 2019 (COVID-19). Methods: A total of 278 patients with COVID-19 admitted to Guangzhou Eighth People's Hospital from January 20 to February 10, 2020 were selected. The general demographic data, epidemiological data, clinical symptoms, laboratory examinations, lung CT imaging, treatment and prognosis were analyzed. Results: There were 130 male patients (46.8%) and 148 females (53.2%) with age (48.1±17.0) years and 88.8% patients between 20-69 years. Two hundred and thirty-six (84.9%) patients had comorbidities. Two hundred and eleven cases (75.9%) were common type. The in-hospital mortality was 0.4% (1/278). The majority (201, 72.3%) were imported cases mainly from Wuhan (89, 44.3%). The most common clinical manifestations were fever (70.9%) and dry cough (61.5%). In some patients, hemoglobin (10.4%), platelets (12.6%) and albumin (55.4%) were lower than the normal range. Other biochemical tests according to liver and function were normal, while lactic dehydrogenase (LDH) was elevated in 61 patients (21.9%), creatine kinase increased in 26 patients (9.4%). Prolonged activated partial thromboplastin time (APTT) was seen in 52 patients (18.7%), D-dimer higher than normal in 140 patients (50.4%), while 117 patients (42.1%) had elevated high-sensitivity C-reactive protein. Typical CT manifestations included single or multiple ground glass shadows especially in lung periphery in early disease which infiltrated and enlarged during progressive stage. Diffuse consolidation with multiple patchy density in severe/critical cases and even "white lung" presented in a few patients. Two hundred and forty-two patients (87.1%) received one or more antiviral agents, 242 (87.1%) combined with antibacterials, 191 (68.7%) with oxygen therapy. There were 198 patients (71.2%) treated with traditional Chinese medicine. Conclusions: COVID-19 could attack patients in all ages with majority of common type and low mortality rate. Clinical manifestations involve multiple organs or systems. Progression of the disease results in critical status which should be paid much attention.

High throughput in vitro and in vivo screening of inland waters of Southern California.

The impact of unmonitored contaminants, also known as contaminants of emerging concern (CECs), on freshwater streams remains largely uncharacterized. Water samples from 31 streams representing urban, agricultural and undeveloped (i.e., open space) land use in Southern California (USA) were analyzed for in vitro and in vivo bioactivity. The extent and magnitude of bioactivity screened using endocrine-responsive cell bioassays and a fish embryo screening assay were low. In contrast, a wider gradient of responses for the aryl hydrocarbon receptor (AhR) assay was observed, which was negatively correlated with a measure of benthic community structure. Both aromatic and non-aromatic CECs were tentatively identified in these samples, but polycyclic aromatic hydrocarbons (PAHs), known AhR agonists in urban environments, were not present at detectable levels. These results suggest that a combination of in vitro and in vivo show potential as screening techniques for biological condition in situ, but that more advanced, comprehensive analytical methods are needed to identify bioactive contaminants.

[Analysis of the influence of iron overload in glucose metabolism in thalassemia major patients].

Objective: This study aimed at determining the characteristics of the glucose homeostasis and its relationship with iron overload of the patients with ß-thalassemia major (ß-TM). Method: From Sun Yat-sen Memorial Hospital between January 2014 and December 2015, a total of 57 transfusion-dependent ß-TM patients with 5-18 years old were enrolled in this study and fasting blood glucose(FBG) and insulin level, serum ferritin (SF), serum iron, transferrin, total iron binding capacity, unsaturated iron binding capacity were determined.Insulin resistance index (IRI), insulin sensitivity index and ß-cell function index (BFI) were also estimated. Besides, in 36 patients cardiac T2* and liver T2* were estimated. Result: (1) Four patients(7%) with ß-TM were diagnosed diabetes mellitus, and 14(24%) had impaired fasting glucose. (2) The incidence of abnormal glucose metabolism was significantly different according to levels of SF and degrees of the cardiac iron overload(χ(2)=9.737, P<0.05; χ(2)=17.027, P<0.05). It rose while the level of SF increased and the degree of cardiac iron overload aggravated. (3) The incidence of abnormal glucose level was not significantly different in cases with different degree of liver iron overload.The severe group of liver iron overload had significantly higher levels of INS, HOMA-ßFI, HOMA-ISI, HOMA-ßFI than the non-severe group (Z=-2.434, -2.515, F=8.658, all P<0.05), while no differences were found in the level of FBG, HOMA-ßFI between two groups. (4) The result of logistic regression analysis indicated that the cardiac T2* was a significant predictor for the incidence of abnormal glucose metabolism in TM patients (P=0.035, OR=1.182%, 95%CI=1.048 to 1.332). Conclusion: The high prevalence of abnormal glucose metabolism in ß-TM patients was mainly closely related with the internal iron overload, especially in organs.The cardiac T2* was an independent risk factor for the incidence of abnormal glucose metabolism in TM patients.

Effect of adjustable gastric banding on quality of life and weight loss in the Helping Evaluate Reduction in Obesity (HERO) registry study: 2 year analysis.

OBJECTIVE: This report from the Helping Evaluate Reduction in Obesity (HERO) Study investigated weight loss, health-related quality of life (HRQOL), and factors predictive of HRQOL improvement during a 2 year period following Lap-Band AP implantation (post-LBAP). RESEARCH DESIGN AND METHODS: This prospective, observational study included patients with 1 and 2 year follow-up data post-LBAP (N = 585). Changes in body mass index (BMI), percentage of weight loss (%WL), excess weight loss (%EWL) and HRQOL (Impact of Weight on Quality of Life [IWQOL]-Lite measure), and differences between <30% EWL and ≥30% EWL subgroups were assessed at 1 and 2 years post-LBAP. Multiple linear regression examined association of %EWL groups with IWQOL-Lite scores controlling for age, gender, region (US vs outside US), household income, employment status, and comorbidities. RESULTS: Most patients were female (80.2%) and from the US (64.8%); overall mean (SD) age was 43.6 (11.28) years and 65.8% of patients had ≥30% EWL at year 2. At 2 years post-LBAP, mean %EWL was 43.5%; %EWL was 12.4% in the <30% EWL group and 59.6% in ≥30% EWL group (P ≤ 0.0001). Changes in IWQOL total and subscores were significantly greater in ≥30% EWL versus <30% EWL patients (all P < 0.0005) at years 1 and 2; Self-Esteem and Physical subscores had the largest changes. Multiple regression analysis showed that patients with ≥30% EWL had clinically meaningful improvements in HRQOL compared with patients having <30% EWL (P ≤ 0.001). Similarly, US patients and females had a clinically significant change in IWQOL score versus their counterparts (P ≤ 0.001). Conversely, income, comorbidities and employment status were not significant predictors of change in IWQOL scores at year 2. CONCLUSIONS: These results support and extend findings regarding the effectiveness of LBAP for weight loss and illustrate the importance of ≥30% EWL as a significant factor in predicting clinically significant improvement in HRQOL 1 and 2 years post-LBAP. CLINICAL TRIAL REGISTRATION: NCT00953173.

Use of biologics for inflammatory bowel disease in Hong Kong: consensus statement.

UNLABELLED: OBJECTIVE; With the increasing use of biologics in patients with inflammatory bowel disease, the Hong Kong IBD Society developed a set of consensus statements intended to serve as local recommendations for clinicians about the appropriate use of biologics for treating inflammatory bowel disease. PARTICIPANTS: The consensus meeting was held on 9 July 2011 in Hong Kong. Draft consensus statements were developed by core members of the Hong Kong IBD Society, including local gastroenterologists and colorectal surgeons experienced in managing patients with inflammatory bowel disease. EVIDENCE: Published literature and conference proceedings on the use of biologics in management of inflammatory bowel disease, and guidelines and consensus issued by different international and regional societies on recommendations for biologics in inflammatory bowel disease patients were reviewed. CONSENSUS PROCESS: Four core members of the consensus group drafted 19 consensus statements through the modified Delphi process. The statements were first circulated among a clinical expert panel of 15 members for review and comments, and were finalised at the consensus meeting through a voting session. A consensus statement was accepted if at least 80% of the participants voted "accepted completely or "accepted with some reservation". CONCLUSIONS: Nineteen consensus statements about inflammatory bowel disease were generated by the clinical expert panel meeting. The statements were divided into four parts which covered: (1) epidemiology of the disease in Hong Kong; (2) treatment of the disease with biologics; (3) screening and contra-indications pertaining to biologics; and (4) patient monitoring after use of biologics. The current statements are the first to describe the appropriate use of biologics in the management of inflammatory bowel disease in Hong Kong, with an aim to provide guidance for local clinical practice.

Contrast-enhanced ct and angiographic findings in hepatic perivascular epithelioid cell tumor.

We report a case of hepatic perivascular epithelioid cell tumor (PEComa) in a woman who was not a carrier of viral hepatitis and had a normal alpha-fetoprotein (AFP) level. CT scan showed a well-enhanced mass in the arterial-phase followed by early washout in the portal venous-phase in the lateral segment of the liver. Angiography revealed a hypervascular tumor in the liver with rapid washout of the contrast. If a hepatic tumor is found in a female patient with normal AFP level who is not a carrier of hepatitis and is free of alcoholic liver cirrhosis, tissue biopsy should precede treatment to avoid misdiagnosis of liver PEComa as hepatocellular carcinoma.

CT and MRI findings correlate with the time-course of unresectable cavernous haemangioma of the liver after fractionated radiotherapy.

We present the case of a 79-year-old female with symptomatic cavernous haemangioma of the liver. The patient had experienced progressive right lateral abdominal pain for years despite increased painkiller use. Surgical resection or transarterial embolisation was not recommended because of the patient's age, cardiovascular comorbidities and large tumour size. Therefore, the patient was treated with 3-dimensional conformal radiotherapy (RT) with a total dose of 30 Gy in 15 fractions. Following RT, the painkillers were tapered from the third month, and complete symptomatic remission was achieved after the ninth month. The measured tumour volume from serial images pre-RT and 3, 9 and 15 months post-RT was 400 ml, 372 ml, 185 ml and 140 ml, respectively. The most dramatic volumetric reduction was found between 3 and 9 months post-RT, whereas the change before or after this period was minimal. The time course of the radiological volumetric changes correlated with that of the clinical symptoms. In addition, the observed vascular changes on serial imaging studies were consistent with the assumed radiobiological effects after fractionated RT.

Immunoglobulin G4-related sclerosing disease: experience with this novel entity in a local hospital.

OBJECTIVE: To review the site of involvement, clinical presentation, and treatment outcome of patients having immunoglobulin G4-related sclerosing disease in a local regional hospital. DESIGN: Retrospective case series. SETTING: Pamela Youde Nethersole Eastern Hospital, Hong Kong. PATIENTS: All patients with a diagnosis of immunoglobulin G4-related sclerosing disease in the hospital diagnosed in the period from April 2008 to March 2010. RESULTS: A total of 12 patients with involvement of various organs were identified. There was a male predominance (male-to-female ratio=5:1). The mean age at diagnosis was 65 years. The salivary glands, biliary tract, pancreas, and cervical lymph nodes were the commonest involved sites. The immunoglobulin G4 level was elevated in 83% of the patients. Patients usually appeared to respond well to steroid treatment. CONCLUSION: Immunoglobulin G4-related sclerosing disease is a systemic disease and can involve various systems.

Incidence of gastroesophageal malignancy in patients with dyspepsia in Hong Kong: implications for screening strategies.

BACKGROUND: A "test-and-treat" strategy for H pylori infection has been recommended in Europe and North America as safe and cost-effective for management of patients with dyspepsia. The primary aim of this study was to determine the frequency of gastroesophageal cancer in 2 groups of patients with dyspepsia: those 45 years of age or younger without "alarm" symptoms (low-risk group) and patients over 45 years of age or any patient with "alarm" symptoms (high-risk group). A secondary aim was to determine the frequency of gastric cancer among patients in the low-risk group with or without a positive serology for H pylori. METHODS: Patients with persistent dyspepsia were recruited from 4 regional hospitals in Hong Kong. Those in the low-risk group were evaluated for H pylori by using a whole blood serology test; they underwent endoscopy within 1 week. Those in the high-risk group and those taking nonsteroidal anti-inflammatory drugs (NSAIDs) underwent endoscopy promptly. Alarm symptoms were as follows: weight loss (10 or more pounds over 8 weeks), recurrent vomiting, dysphagia, bleeding, or anemia. RESULTS: Of 2627 patients enrolled, 1017 were in the low-risk group and 1610 in the high-risk group. Twenty-three patients (0.9%) had gastroesophageal cancers (20 gastric, 3 esophageal). Four patients with cancer (17.4%) were in the low-risk group (3 gastric, 1 esophageal); all except the patient with esophageal cancer had a positive serology test. In the high-risk group, 19 patients had cancer (17 gastric, 2 esophageal). CONCLUSION: Gastric cancer is relatively frequent among young patients with dyspepsia who have no alarm features in Hong Kong. This finding raises concerns as to the safety of the "test-and-treat" strategy for the management of patients with dyspepsia in Asia.

Production of cloned goats from enucleated oocytes injected with cumulus cell nuclei or fused with cumulus cells.

This study was designed to produce cloned goats from cumulus cells. Cloning donor nuclei were from cumulus cells either freshly isolated or cultured in vitro. Enucleated oocytes were either injected with cumulus cell nuclei without piezo-driven manipulator (injection method) or fused with cumulus cells (fusion method). The survival rate of cloned embryos, obtained by injection, was higher than that derived from fusion (62.7 and 45.9%, respectively). Two cloned goats were derived by fusion with in vitro cultured cumulus cells without starvation, but died shortly after natural birth, from respiratory difficulties. Their birth weights (2.23 kg and 2.03 kg) were within the normal range (2.0-2.7 kg) and postmortem analysis revealed no morphological abnormalities. The third cloned goat, derived by injection of nuclei from freshly isolated cumulus cells, weighed 3.3 kg at birth, and was 37% overweight compared with the average weight of the same species. This goat is healthy and well as this paper is being prepared. Nested PCR-RFLP analysis confirmed that all the cloned goats were derived from the donor cells.

[The recombinant vaccinia viruses expressing HPV type 16 wild or mutant E7 protein elicit immunity against tumor cells in mice].

OBJECTIVE: To select mutants of HPV 16 E7 suitable for vaccine development. METHODS: Several recombinant vaccinia viruses (VwE7, VmE7-1, and VmE7-2) expressing wild E7 or its mutants, ME7-1 (24G26G) and ME7-2 (24G26G91G) respectively, were employed to study their antigenicity and anti tumor activity. RESULTS: Both VmE7-1 and VwE7 could elicit cytotoxic T lymphocytes (CTL)and protect mice against tumor cells challenge, but VmE7-2 could not induce the immune reactions compared with VmE7-1 and VwE7. CONCLUSIONS: It suggested that ME7-1 could be used to develop a therapeutic vaccine for cervical cancer.

Electronic and vibrational spectra of a series of substituted carbazole derivatives.

The FTIR and FTR spectra of halogen (Cl, Br, I) substituted carbazole and their N-acetic and propionic acids have been recorded. A number of lines have been assigned on the basis of previous studies on the parent compound and by comparisons with the characteristic vibrations of their constituent structural units as well as comparing the spectra from FTIR and FTR. Some substituent-sensitive bands and characteristic bands were found. The electronic absorption spectra of these compounds in acetonitrile were also measured and are briefly discussed.

[Genetics and expression stability of exogenous gene construct in transgenic mice].

Transgenic mice were produced by introduced exogene construct lambda 106, an expression construct of HBsAg gene directed by bovine alpha-S1 casein gene, with microinjection. Gene integration test with PCR-Southern hybridization, shows that the construct integration rate is 56% (17/30) and expressed rate, by ELISA, of target gene product HBsAg is 100% (8/8) in the first generation. Generation trailing test suggests that the gene construct can be stably inherited across generation after generation, and expressed more or less than parents among offspring. However positive rate of offspring does not follow genetic ratio that exogenous gene can be integrated randomly into a single site on chromosomes. There may be a machinery of multi-sites for exo-gene integration. Changes of the target gene expression in the offsprings may be related to position effect, changing of gene copy number and changing of chromatin imprinting pattern when parent's genome information was delivered to their progeny.

High performance liquid chromatographic determination of N-nitrosoamines by pre-column fluorescence derivatization with acridone-N-acetyl chloride.

A sensitive high performance liquid chromatographic method for the determination of N-nitrosoamines with pre-column fluorescence derivatization has been developed. N-nitrosoamines are first changed into secondary amines using denitrosation reagent, then react with acridone-N-acetyl chloride (ARC-Cl) to produce corresponding secondary amine derivatives, which exhibit a strong fluorescence. Maximum emission for ARC derivatives is 430 nm (lambda(ex) 404 nm). The labelled derivatives are very stable, less than 4% decomposition occurs after heating at 40 degrees C for 24 h. Fluorescence intensities of derivatives are higher in neutral and alkaline than in acidic solutions. This method, in conjunction with a multi-gradient program, offers a baseline resolution of the ARC derivatives from a linear acetonitrile gradient. Separation is carried out on a reverse phase C(18) column. Derivatization and chromatographic conditions are optimized. The relative standard deviation (n=6) at an analytical concentration of 10 pmol of each N-nitroamine is less than 4.5%. The detection limits at the fmol level. The method described is also suitable for analysis of other amino compounds in different biological samples.

Transient expression of hepatitis B virus surface antigen (HBsAg) and human erythropoietin (hEPO) genes in milk after direct introduction into ewe.

The ability to deliver nonviral DNA directly into animals would provide major practical and economic benefits. To pursue this potential, as a preliminary approach, the expression in mammary epithelial cells with nonviral DNA ending HBsAg and hEPO was investigated by in vivo delivery directly into mammary gland Either the bovine asl-casein-HBsAg or the WAE-hEPO gene construct was introduced into mammary glands of dm by mammary artery injection. A single injection of 10(11) copies of DNA construct was implemented for a doe. Transient expression of the constructs in milk collected from milk letdown by induction up to 19 d after injection was measured with an hEPO ELISA kit from Boehringer Mannheim (Cat. No. 1 693 417) for rhEPO, and a HBsAg-ELISA kit (Abbott Lab. USA) for rHBsAg. The treated animals showed mean concentration of recombinant molecules at 16 microg/L for rHBsAg, and 2 mg/L for rhEPO in milk.

Use of polymerase chain reaction to provide prognostic information on human cytomegalovirus disease after liver transplantation.

Sixty-four consecutive liver transplant patients receiving 76 organs have been monitored for human cytomegalovirus (HCMV) in blood and urine posttransplantation using a polymerase chain reaction (PCR) assay that amplifies a 149 base pair fragment of the glycoprotein B gene. Six hundred and twenty-six blood and 310 urine samples were analysed during surveillance. Thirty-two patients had CMV infection (50%), 12 of whim progressed to HCMV disease. Detection of HCMV in either blood or urine was significantly associated with the presence or development of HCMV disease (blood, P < 0.00001; urine, P = 0.0033). All cases of HCMV disease were detected as PCR-positive in blood, although due to sampling only 50% of these patients were PCR-positive prior to disease onset. HCMV infection and disease were more likely in patients who suffered rejection (P < 0.001). In addition, the median amounts of augmented prednisolone were higher in patients with HCMV infection and disease. In all cases, augmented prednisolone preceded HCMV infection/disease. There was no statistical association between CMV infection and death. Overall, the results show that routine use of PCR for HCMV in surveillance samples of blood and urine of liver transplant recipients can provide diagnostic and prognostic information. However, its ability to provide prognostic information is directly related to the availability of appropriate surveillance samples, emphasising the importance of the routine acquisition of such samples in patient management to allow preemptive anti-HCMV therapy.

Expression of HBsAg gene in transgenic goats under direction of bovine alpha-S1 casein control sequence.

An expressive construct combining hepatitis B surface antigen gene and bovine alpha-S1 casein control sequence (a 16-kb fragment), lambda 106, was made successfully using DNA recombination technology. The construct was then introduced into fertilized goat eggs with a transgenic technique. As the eggs developed into adults which, in turn, began to secrete milk after parturition, ELISA assay demonstrated HBsAg in the milk, thus showing successful expression of the construct in the mammary gland of the G0 transgenic goats and the secretion of the expression product into the milk.

Analysis of Chinese isolates of Trichinella spiralis by molecular biotechnology.

OBJECTIVE: To investigate the relationships among Trichinella spiralis isolates obtained from different hosts and geographical regions in China. MATERIALS AND METHODS: Six isolates of Trichinella spiralis obtained from Changchun, Tianjin, Xi'an, Henan and Yunnan were detected. All the isolates were collected from pigs or dogs. Restriction fragment length polymorphism (RFLP), isoenzyme electrophoresis and soluble protein analysis were used. RESULTS: Distinctive banding patterns in restriction maps were seen between Changchun and other isolates studied. A cloned specific repetitive DNA sequence (1.12 kb) from Changchun isolate was then selected to prepare probe for Southern blotting of DNA fragments. The hybridizing banding patterns among the isolates were different and only the Changchun isolate showed the 1.12 kb band. The Changchun isolate was also distinguishable from the other isolates in isoenzyme patterns of GP1, G6PD, HK, 6PGDH and AK, as well as in isoelectric focusing electrophoresis where the Changchun isolate presented a specific band at 4.1 P1. CONCLUSIONS: There are at least two different biological types of Trichinella spiralis in China and the differences between them may be attributed to different geographical origins and/or different hosts.

Restriction fragment length polymorphism (RFLP) analysis of genomic DNA of 5 strains of Trichinella spiralis in China.

Five restriction endonucleases were used to digest genomic DNA from 5 isolates of Trichinella spiralis obtained from Changchun, Tianjin, Xian, Henan and Yunnan. All the isolates were secured from pigs except the Changchun strain which came from dog. The DNA fragments digested by endonuclease were separated by agarose gel electrophoresis. The Changchun isolate had a EcoRI band at 1.12kb and a DraI band at 1.97kb which were unique to this isolate. A cloned specific repetitive DNA sequence (1.12kb) from the Changchun strain was selected to prepare a probe for the Southern blotting of EcoRI restriction DNA fragments for the 5 isolates. The 1.12kb hybridizing band did not appear except in the Changchun isolate. These results seem to indicate that there are differences between the isolates obtained from hosts in different geographical regions.