A technique for registering digital dental casts onto cone beam computed tomography scans with excessive metallic artifacts.

This article describes a method of integrating digital dental casts into cone beam computed tomography (CBCT) scans in virtual implant planning in situations with an excessive number of metal artifacts. This technique requires the use of a prefabricated registration tray to provide a common landmark; is noninvasive, minimally time-consuming, and cost-effective; and requires only a single registration and minimal exposure to radiation.

PPARγ and mitophagy are involved in hypoxia/reoxygenation-induced renal tubular epithelial cells injury.

Renal tubular epithelial cell (RTEC) injury is the main cause and common pathological process of various renal diseases. Mitochondrial dysfunction (MtD) is a pathological process after renal injury. Mitophagy is vital for mitochondrial function. Hypoxia is a common cause of RTEC injury. Peroxisome proliferator-activated receptor γ (PPARγ) is involved in cell proliferation, apoptosis, and inflammation. Previous studies have shown that the low expression of PPARγ might be involved in hypoxia-induced RTEC injury. The present study aimed to investigate the correlation between PPARγ and mitophagy in damaged RTEC in the hypoxia/reoxygenation (HR) model. The results showed that HR inhibited the expression of PPARγ, but increased the expression of LC3II, Atg5, SQSTM1/P62, and PINK1 in a time-dependent manner. Moreover, mitochondrial DNA (mt DNA) copy number, mitochondria membrane potential (MMP) levels, ATP content, and cell viability were decreased in hypoxic RTECs, the expression of SQSTM1/P62 and PINK1, the release of cytochrome c (cyt C), and production of reactive oxygen species (ROS) were increased. Mitochondrial-containing autophagosomes (APs) were detected using transmission election microscope (TEM) and laser scanning confocal microscope (LSCM). Furthermore, PPARγ protein expression was negatively correlated with that of LC3II, PINK1, and the positive rate of RTEC-containing mitochondrial-containing APs (all p < .05), but positively correlated with cell viability, MMP level, and ATP content (all p < .05). These data suggested that PPARγ and mitophagy are involved in the RTEC injury process. Thus, a close association could be detected between PPARγ and mitophagy in HR-induced RTEC injury, albeit additional investigation is imperative.

Electrochemical Detection and Distribution Analysis of ß-Catenin for the Evaluation of Invasion and Metastasis in Hepatocellular Carcinoma.

Pro-metastatic cell signaling controls the switch to distant metastasis and the final cancer death. In hepatocellular carcinoma (HCC), this death switch is turned on by the multiprotein interactions of ß-catenin with many transcription factors, so a method to assay the bioactivity of ß-catenin to participate in these pro-metastatic protein/protein interactions has been proposed in this work. This method employs cost-effective peptide-based protein targeting ligands, while the electrochemical catalytic cross-linking in this method also "finalize" the noncovalent molecular recognition, so that the robustness can be improved to enable detection of relatively more complex biosamples. In studying clinical samples with the proposed method, the cellular distribution and overall expression of ß-catenin show a parallel with the pathological grade of the sample, particularly, nuclear translocation. The pro-metastatic activation of ß-catenin can also be observed as evidently correlated with higher-grade cases, suggesting the active role of ß-catenin in promoting metastasis. According to these results, the proposed method may have the prospective use as a prognostic tool for evaluating the potential of invasion and metastasis in cancer.

Characteristic comparison between canine and human dental mesenchymal stem cells for periodontal regeneration research in preclinical animal studies.

The effectiveness of stem cell-based periodontal tissue engineering need to be assessed by preclinical animal studies. Dog models are widely used animal models; however, there are not sufficient data on characterization of canine dental mesenchymal stem cells. Therefore, we aimed to compare the characteristics among canine and human periodontal ligament stem cells and canine and human dental pulp stem cells. Canine periodontal ligament stem cells and dental pulp stem cells showed significantly weaker clonogenic capability, and proliferation and migration capacity, and they displayed lower positive rates for CD90, CD73, CD105, and STRO-1. All of these canine and human cells showed multilineage differentiation potential. After osteogenic induction, the expression of alkaline phosphatase was obviously upregulated in human dental mesenchymal stem cells, but it was not upregulated in canine dental pulp stem cells. Other osteogenic genes, such as runt-related transcription factor 2 and bone morphogenetic protein 2, were upregulated in all induced canine and human cells, but their upregulation occurred later in canine cells. These results confirmed the stem cell properties of canine mesenchymal stem cells, but also suggested that more attention should be paid to the choice of appropriate research approaches, osteogenic gene markers, and time points for the utilization of canine dental mesenchymal stem cells due to their distinct characteristics.

[Relationship between glucose-6-phosphate dehydrogenase gene mutations and neonatal jaundice in Naning, Guangxi].

OBJECTIVE: To study the correlation between glucose-6-phosphate dehydrogenase (G-6-PD) activities and three common mutations of G-6-PD gene G1388A, G1376T and A95G and investigate the effects of G-6-PD gene mutations on neonatal jaundice in Nanning, Guangxi. METHODS: One hundred and twenty-four neonates from Nanning, Guangxi, with hyperbilirubinemia were enrolled. The ARMS-PCR and PCR/REA methods were used to determine G-6-PD gene mutations. G-6-PD activities were measured using the NBT method. The incidence of acute bilirubin encephalopathy and the peak bilirubin concentration 72 hrs after birth were compared between the neonates with different genotypes and between the G-6-PD mutation and normal groups. The risk of blood serum bilirubin >340 mumol/L was evaluated by logistic regression analysis. RESULTS: Of the 124 cases, gene mutations were found in 37 cases, including G1388A (n=20), G1376T (n=14), A95G (n=4) and G1388A+A95G (n=1). Five cases (25%) showed normal G-6-PD activities in the G1388A gene mutation group and 4 (29%) had normal G-6-PD activities in the G1376T G1388A gene mutation group. All of 4 cases of A95G G1388A gene mutation showed a deficiency of G-6-PD activities. There were no significant differences in the incidence of acute bilirubin encephalopathy and the peak bilirubin concentration 72 hrs after birth between the G1388A and G1376T G1388A gene mutation groups. The incidence of acute bilirubin encephalopathy, the peak bilirubin concentration 72 hrs after birth and the risk of serum bilirubin >340 micromol/L in the G-6-PD mutation group were not different from the normal group. CONCLUSIONS: G1388A, G1376T and A95G are common G-6-PD gene mutations in Nanning, Guangxi. The false negative results may be received when the NBT method is used for diagnosis of G-6-PD deficiency. There are similar effects on the incidence of acute bilirubin encephalopathy and the peak bilirubin concentration 72 hrs after birth between different gene mutation groups. G-6-PD gene mutations alone may not contribute to the development of acute bilirubin encephalopathy and the changes of peak bilirubin concentration 72 hrs after birth and the risk of serum bilirubin >340 micromol/L.

Proximity ligation-induced assembly of DNAzymes for simple and cost-effective colourimetric detection of proteins with high sensitivity.

A novel colourimetric method for protein assays is proposed based on proximity ligation induced assembly of Mg(2+)-dependent DNAzymes, which may offer simple, cost-effective, sensitive and selective detection of the target protein.

Simple electrochemical sensing of attomolar proteins using fabricated complexes with enhanced surface binding avidity.

Various strategies have been proposed for the detection of disease protein biomarkers; however, most methods are too expensive, cumbersome or limited in sensitivity for clinical use. Here, we report that a fabricated complex can be used as a powerful tool to detect trace proteins in complex samples. In this strategy, a DNA-protein complex that comprises of one target molecule and two or more deoxyribozyme-containing probes can exhibit autonomous cleavage behavior on the surface of the substrate DNA modified electrode. In the meantime, the complex can remove the cleaved DNA fragment from the electrode surface by taking advantage of the proximity effect. The proposed approach allows one-step and highly sensitive detection of a variety of targets based on the changes of the direct electrochemical readout. Moreover, this method may also have considerable advantages over the commonly reported DNA amplification-assisted immunoassays, particularly in terms of assay simplicity and cost, which may hold great potential for application in resource-constrained regions.

Colorimetric assay for protein detection based on "nano-pumpkin" induced aggregation of peptide-decorated gold nanoparticles.

Small peptide can be used as an effective biological recognition element and provide an alternative tool for protein detection. However, the development of peptide-based detecting strategy still remains elusive due to the difficulty of signal transduction. Herein, we report a peptide-based colorimetric strategy for the detection of disease biomarker by using vascular endothelial growth factor receptor 1 (Flt-1) as an example. In this strategy, N-terminal aromatic residue-containing peptide modified gold nanoparticles (GNPs) can form bulky aggregate by the introduction of cucurbit[8]uril (CB[8]) that can selectively accommodate two N-terminal aromatic residue of peptides simultaneously regardless of their sequences. However, in the presence of Flt-1, the peptide can specifically bind to the protein molecule and the N-terminal aromatic residue will be occupied, resulting in little aggregation of GNPs. By taking advantage of the highly affinitive peptide and efficiency cross-linking effect of CB[8] to GNPs, colorimetric assay for protein detection can be achieved with a detection limit of 0.2 nM, which is comparable with traditional methods. The feasibility of our method has also been demonstrated in spiked serum sample, indicating potential application in the future.

An array-based approach to determine different subtype and differentiation of non-small cell lung cancer.

Simple and accurate methods of discriminating subtype or differentiation of human tumor are critical for designing treatment strategies and predicting disease prognosis, and the currently used method to determine the two important factors mainly depends on histological examination by microscopy observation, which is laborious, highly trained operator required, and prone to be disruptive due to individual-to-individual judgment. Here we report a novel array-based method based on the interaction of graphene oxide (GO) and single-strand DNA modified gold nanoparticles (ssDNA-AuNPs) to distinguish between different subtypes and grades of tumors through their overall intracellular proteome signatures. Strategically, we first select eight proteins at 0.5 nM concentration in buffer or 10 nM in human serum to verify the discriminant ability of our method, then choose adenocarcinoma and squamous-cell carcinoma that account for 90% non-small cell lung cancer, as well as their respective three tumor grades as model system to provide a realistic testing ground for clinical cancer analysis. Consequently, total differentiation between different subtype and grade of tumor tissues has been achieved with as little as 100 ng of intracellular protein, suggesting the high sensitivity and selectivity of this sensor array. Overall, this array-based approach may provide the possibility for unbiased and simplified personalized tumor classification diagnostics in the future.

Ultrasensitive detection of lead ion based on target induced assembly of DNAzyme modified gold nanoparticle and graphene oxide.

In this paper, we report a novel colorimetric strategy for the detection of small molecules by using Pb(2+) ion as an example. In this strategy, DNAzyme duplex modified gold nanoparticles (GNPs) are designed to be unable to interact with graphene oxide (GO). However, in the presence of Pb(2+), the substrate strand of the DNAzyme is cleaved at its cleavage site, resulting in the disassembly of the DNAzyme duplex modified GNPs into three parts, i.e., the 3'- and 5'-fragments of substrate strand and the DNAzyme strand modified GNPs. By taking advantage of the efficient cross-linking effect of ssDNA-GNPs to GO, colorimetric sensor for the detection of the metal ion can be fabricated with a detection limit of 100 pM, which is much lower than the previous reports. This colorimetric method has also been used for the determination of Pb(2+) in the tap water of the local city and the water from a reservoir with satisfactory results, so it may have potential applications in the future.

[Roles of UGT 1A1 gene mutation in the development of neonatal hyperbilirubinemia in Guangxi].

OBJECTIVE: Neonatal unconjugated hyperbilirubinemia is one of the most common conditions encountered by the practicing pediatricians. Although it is usually self-limited and benign, the condition is of importance because of the rare instances in which severe hyperbilirubinemia can lead to bilirubin encephalopathy or kernicterus. The uridine diphosphate-glucuronosyl transferase 1A1 (UGT 1A1) gene controls bilirubin conjugation by determining the structure of the enzyme glucuronosyltransferase, which is synthesized in the hepatocyte. In the recent years much has been learned about the relationship between UGT 1A1 gene mutation and neonatal hyperbilirubinemia. This study aimed to investigate the roles of UGT 1A1 gene mutation in the development of neonatal hyperbilirubinemia in Guangxi. METHODS: A total of 73 cases with hyperbilirubinemia and 31 healthy neonates were enrolled. UGT 1A1 G71R genotypes were identified by the (amplification refractory mutation system, ARMS) and direct sequencing method in all the neonates. To analyze the incidence of bilirubin encephalopathy, the peak (total serum bilirubin, TSB) concentration after 72 hours of age, and the possibility of TSB > 20 mg/dl of each group. RESULTS: (1) The frequencies of allele G71R were 0.1915 in this study, 0.2329 in hyperbilirubinemia group vs. 0.097 in healthy groups. The allele gene frequency of G71R in neonatal hyperbilirubinemia was higher than that in the normal group (P < 0.05). (2) Homozygous neonates had higher possibility to develop bilirubin encephalopathy and higher TSB concentration 72 hours after birth (28.57%, 23.12 ± 4.58) than the normal group (0%, 17.68 ± 2.69). The difference between the former two was significant (P < 0.001). (3) The TSB of the 5 neonates was > 20 mg/dl in G71R homozygous type, the odds ratio and 95%CI were 7.955 (1.349, 46.899). CONCLUSION: (1) G71R mutation gene was associated with neonatal jaundice in Guangxi region. (2) The possibility of TSB > 20 mg/dl in G71R homozygous was higher than those of the wild-type. (3) The incidence of bilirubin encephalopathy and TSB concentration after 72 hours of age for neonates who were homozygous to G71R gene were higher than the wild-type.

[Evaluation on degradation of Karst forest community and human disturbance].

Fire, reclamation, herd, and cut led to degradation of Karst forest in Guizhou Province. Five indexes as height, dominance, percentage of asexual individual, biomass, and percentage of shade-tolerant for evaluating community degradation were selected. Degraded communities were divided into six degraded grades (A-F). Community structure and function fluctuated normally in climax (A) under nature force or light human disturbance. While effect of disturbance was preponderated over the range of community fluctuation, climax community degraded evidently, and degraded degree of communities increased gradually. Degraded grades of communities were consistent to succession stages of degraded community. In degraded process, the key factor was decrease of biomass and shade-tolerant species. Degraded communities due to fire, herd, and reclamation were distributed in grades C-F, and degraded community due to cut was in grades B-C. Amount of asexual individual was influenced by disturbance type, and the amount in degraded communities due to fire and cut was more than that due to reclamation and herd. Degraded degree of different disturbed community was in order of cut community < cleared community < herded community < fired community.