Relationship between Clinical Symptoms and the Microbiota in Advanced Caries

INTRODUCTION

The composition and relative abundance of bacterial species change throughout the development of dental caries; however, how these changes relate to clinical symptoms remains elusive. In this study, we explored the relationship between clinical symptoms and specific microorganisms in advanced dentinal caries.

METHODS

A total of 111 permanent premolars and molars were used to simulate the progression from caries to pulpitis indirectly. Clinical symptoms were evaluated, and teeth were diagnosed according to the diagnostic criteria of the American Association of Endodontics. Samples were collected for 16S ribosomal DNA sequencing. Associations between the microbiota and clinical symptoms/diagnosis and the relationship between alpha diversity and clinical symptoms/diagnosis were evaluated independently by the linear discriminant analysis effect size and Spearman rank correlation analyses.

RESULTS

The 16S ribosomal DNA sequences were assigned to 13,852 operational taxonomic units. The linear discriminant analysis effect size and Spearman correlations unveiled negative associations between the relative abundance of Bacteroidia and Gammaproteobacteria and referred pain, Gammaproteobacteria and the electric pulp test response, and Actinomyces and Propionibacterium and diagnosis (r < 0.0, P < .05). Conversely, the relative abundance of Lactobacillus was positively correlated to referred pain, the cold test, the percussion response, and diagnosis (r > 0, P < .05). Lactobillus reuteri, a probiotic bacterium, was more abundant in teeth with referred pain and teeth diagnosed with symptomatic irreversible pulpitis. The Spearman correlation between alpha diversity and clinical symptoms/diagnosis was not significant (P > .05).

CONCLUSIONS

Clinical symptoms and diagnosis were significantly associated with specific microorganisms in the most advanced layers of dentinal caries.

Rapid isolation of non-aflatoxigenic Aspergillus flavus strains

In the present study, a method for screening non-aflatoxigenic Aspergillus flavus in soil samples collected from major peanut-growing regions of China was developed. The single colonies were picked and cultured on Aspergillus flavus and parasiticus agar (AFPA). If the reverse side of the colony on AFPA was orange-coloured, it was considered A. flavus or Aspergillus parasiticus. After the genomic DNA of each strain was extracted, 28S rRNA and calmodulin were amplified and sequenced to determine the species. The key gene, aflR, was amplified and digested via polymerase chain reaction-restriction fragment length polymorphism. The aflatoxigenic A. flavus and the non-aflatoxigenic A. flavus and A. parasiticus were distinguished by enzyme digestion of aflR. 156 strains of A. flavus were screened, which consisted of 135 aflatoxigenic and 21 non-aflatoxigenic strains. The aflatoxin producing ability of each strain was confirmed using solid-state fermentation experiments. Using the method developed in the present study, we confirmed that the non-aflatoxigenic A. flavus strains isolated lost their capacity to produce aflatoxins. Considering there could be some alterations in other functional genes, some non-aflatoxigenic strains could be identified inaccurately as aflatoxigenic strains, although that did not occur in the present study. The growth of non-aflatoxigenic A. flavus was observed, and the most rapidly growing non-aflatoxigenic strain was selected for plate confrontation assays and toxic mixed culture experiments. The inhibition rate of non-aflatoxigenic A. flavus against aflatoxigenic A. flavus was 55.4 and 72.6% in potato dextrose agar (PDA) plate and natural soybean medium, respectively. The screened non-aflatoxigenic A. flavus strains provide a microbial resource for biological control of aflatoxin contamination.

Chinese expert group consensus on diagnosis and clinical management of osteoradionecrosis of the mandible

Osteoradionecrosis of the mandible (MORN) is one of the most devastating complications caused by radiation therapy in the head and neck region. It is characterized by infection and chronic necrosis of the mandible as the main manifestation. Clinically, MORN-related symptoms include swelling, pain, dysphagia, trismus, masticatory or speech disorders, refractory orocutaneous fistula, bone exposure, and even pathological fracture. MORN has become a challenging clinical problem for oral and maxillofacial surgeons to deal with, but thus far, this problem has not been solved due to the lack of widely accepted treatment algorithms or guidelines. Because of the nonexistence of standardized treatment criteria, most clinical treatment against MORN nowadays is largely based on controversial empirical understandings, while recommendations on post-therapeutic evaluations are scarce. Therefore, to further unify and standardize the diagnosis and treatment of MORN, to decrease the huge waste of medical resources, and ultimately, to improve the wellbeing of the patients, the Chinese Society of Oral and Maxillofacial Surgery (CSOMS) convened an expert panel specialized in MORN from 16 domestic medical colleges and affiliated hospitals to discuss the spectrum of diagnosis and and formulate treatment. In addition, consensus recommendations were also revised with a comprehensive literature review of the previous treatment experiences and research pearls. This 'expert consensus statement on diagnosis and clinical management of MORN' is for clinical reference.

[Research progress on urogenital function preservation in extralevator abdominoperineal resection]

Extralevator abdominoperineal excision (ELAPE) has been suggested to potentially improve oncological outcomes in advanced low rectal cancer patients. However, the urogenital function impairment as one of the main complications deteriorates the quality of life in these patients. The key point to prevent urogenital function impairment is to avoid autonomic nerve injury, including the superior and inferior hypogastric nerve plexus and neurovascular bundle. Three areas should be especially focused during surgery, including the posterolateral aspect of the prostate during the separation of the rectum from prostate, the lateral wall of ischioanal fossa and the area in front of anal canal. Previous presumption supposed that extended resection, though promoting oncologic outcomes, might lead to enlarged injury to surrounding vessels and nerves that deteriorated patients' urogenital function. But recent studies show that postoperative urogenital function outcomes of rectal cancer patients who underwent ELAPE are not inferior to conventional APE after the induction of minimal invasive approaches including laparoscopic and robotic surgery. Their quality of life can be comparable with patients who underwent conventional APE, and are even better in some particular area. Moreover, as further improvement of ELAPE procedure has been made, the concept of individualized ELAPE addressed the importance of personalized surgical procedure based on tumor stage and location, dedicating to avoid injury to vessels and nerves through preserving more surrounding tissues. Urogenital function outcomes, as part of postoperative outcomes, get more and more attention in recent years. We review current studies on urogenital function after ELAPE from anatomy to clinical research, in order to raise surgeons' attention of nerve preservation technique and to improve their understanding of ELAPE procedure.

[A review of immune-related adverse events associated with immunotherapy]

Immune checkpoint inhibitors have been approved for clinical application in China. However, the increased immune-related adverse event (irAE) needs more attention. This review summarized the incidence, characteristic clinical manifestation and treatment of irAEs associated with programmed cell death protein-1(PD-1) and programmed cell death ligand-1(PD-L1) inhibitors. To have a deep insight into irAE, the potential mechanisms, the different incidences of cancer types, influencing factors and the direction of future research were also discussed here to provide guidance for clinical oncologist to identify and monitor irAE.

Transport and photoelectric properties of vertical black phosphorus heterojunctions

The photoelectric response of heterostructures formed by BP with insulator BN, semiconductor MoS₂, and conductor graphene.

Resistive Switching Mechanism of HfO₂ Based Resistance Random Access Memory Devices with Different Electrode Materials

This study investigated the impact of electrode materials on HfO₂-based RRAM devices. The research includes three types of electrode materials: (1) the electrodes with strong ability of oxygen reservoirs; (2) the electrode with poor ability of oxygen reservoirs; (3) the active electrode with injection ability. Through implementing different combinations of electrodes, three types of switching modes were obtained and the relative conduction mechanism was analyzed, as well as conduction model. Those studies may offer ways of using electrodes to control the resistive switching processes and fabricating the RRAM devices with good performance.

Targeted inhibition of β-catenin by miR-320 and decreased MMP-13 expression in suppressing chondrocyte collagen degradation

OBJECTIVE

Wnt/β-catenin pathway plays a critical role in modulating embryonic development, cell growth, and differentiation. The over-expression of β-catenin activates this pathway and up-regulates expression of matrix metalloproteinase-13 (MMP-13), and promotes matrix degradation and occurrence of osteoarthritis (OA). This study aims to explore the effect of miR-320 expression in OA chondrocyte and underlying mechanisms.

PATIENTS AND METHODS

Chondrocyte tissues from OA patients and normal individuals were collected for the detection of expression levels of miR-320, β-catenin, MMP-13, and alpha-1 chain of type II collagen (COL2A1). Dual luciferase reporter assay was performed to test targeted regulation between miR-320 and β-catenin. IL-1β was used to simulate in vitro cultured chondrocytes, which were transfected with miR-320 mimic and/or si-β-catenin, followed by quantification of miR-320, β-catenin, MMP-13, and COL2A1.

RESULTS

In chondrocytes of OA patients, expression of microRNA (miR)-320 is decreased. Bioinformatics analysis revealed complementary binding sites between miR-320 and β-catenin. Compared to control group, increasing levels of β-catenin and MMP-13 expression with reduction of miR-320 and COL2A1 expressions were observed in OA chondrocytes. Transfection of miR-320 mimic and/or si-β-catenin depressed expression of β-catenin and MMP-13 inside chondrocytes, accompanied with elevation of COL2A1 expression.

CONCLUSIONS

MiR-320 expression in OA chondrocyte is decreased, accompanied with up regulation of β-catenin and MMP-13. MiR-320 can inhibit β-catenin and MMP-13 expressions, elevates COL2A1 expression, which provides novel insights for the treatment of osteoarthritis.

Demonstration of Machine Learning-Based Model-Independent Stabilization of Source Properties in Synchrotron Light Sources

Synchrotron light sources, arguably among the most powerful tools of modern scientific discovery, are presently undergoing a major transformation to provide orders of magnitude higher brightness and transverse coherence enabling the most demanding experiments. In these experiments, overall source stability will soon be limited by achievable levels of electron beam size stability, presently on the order of several microns, which is still 1-2 orders of magnitude larger than already demonstrated stability of source position and current. Until now source size stabilization has been achieved through corrections based on a combination of static predetermined physics models and lengthy calibration measurements, periodically repeated to counteract drift in the accelerator and instrumentation. We now demonstrate for the first time how the application of machine learning allows for a physics- and model-independent stabilization of source size relying only on previously existing instrumentation. Such feed-forward correction based on a neural network that can be continuously online retrained achieves source size stability as low as 0.2  μm (0.4%) rms, which results in overall source stability approaching the subpercent noise floor of the most sensitive experiments.

[Comparison of antibiotics and saline irrigation with tube drainage in the treatment of postoperative abdominal and pelvic infectious effusion]

Objective: To compare the efficiency of saline irrigation, antibiotics irrigation and high-concentration antibiotics perfusion with tube drainage in the treatment of infectious effusion. Methods: Clinical and sonographic features of abdominal and pelvic infectious effusion of 64 patients with malignant tumor collected from September 2013 to September 2017 were retrospectively analyzed. The changes of effusion size and temperature, catheterization time were evaluated in saline irrigation group and antibiotics irrigation group. The catheterization time was compared between antibiotics irrigation group and high-concentration antibiotics perfusion group. Results: The effective rates of the saline irrigation group and the antibiotics irrigation group were 68.6% and 86.8%, respectively, and the times of catheterization were 11.9±8.4 days and 7.8±4.8 days, respectively, with significantly statistical difference (both P<0.05). However, the effective rates of the antibiotics irrigation group and the high concentration antibiotic perfusion group were 86.8% and 100.0%, respectively (P=0.067), while the times of catheterization were 7.8±4.8 days and 3.6±3.1 days, respectively (P<0.001). Conclusion: The antibiotic irrigation with tube drainage, especially the high concentration perfusion is more effective than saline in the treatment of abdominal and pelvic infection effusion.

[Long-term observation of morphological changes of the inner retinal after internal limiting membrane peeling in macular hole surgery]

Objective: To investigate the characteristics of morphological changes of inner retinal layer after internal limiting membrane peeling in macular hole surgery. Methods: Retrospective case study. Patients with idiopathic macular hole from 2015 to 2018 underwent vitrectomy+internal limiting membrane peeling (inverting)+ gas tamponade in China-Japan Friendship Hospital were investigated. A total of 19 eyes (17 patients) were enrolled, including 4 males (4 eyes) and 13 females (15 eyes). The average age was 62.74±5.25 years. Optical coherence tomography (OCT) was used to obtain the topographic maps of retinal thickness, the thickness of retinal ganglion cell complex and probability maps, and the Angio/en-face maps of macular retina. The characteristics of the morphological changes of the inner retinal were comprehensively analyzed. Results: Among 19 eyes, 9 eyes had internal limiting membrane peeling, 8 eyes had lotus-like internal limiting membrane inverting, and 2 eyes had the uper180 degrees internal limiting membrane inverting. The minimum diameter of macular hole was (543.06+220.17) μm and the maximum diameter was (947.18+319.12) μm. The follow-up time was (21.05+9.66) months, and the visual acuity was 0.45+0.35 at the last follow-up. In the 19 eyes, all the macular holes were closed postoperatively and dissociated optic nerve fiber layer appearance (DONFL) and concentric macular dark spots (CMDS) all showed, as well as mGCC thinning. The changes of CMDS and mGCC in 2 eyes in the uper180 degrees internal limiting membrane inverting group were mainly seen in the upper retina and in the remaining 17 eyes were seen diffused around the macula, which roughly corresponded to the extent of internal limiting membrane peeling. Two eyes showed clear decrease of retinal capillary density on Angio/map. Conclusions: Long-term morphological changes of the inner retinal after internal limiting membrane peeling in macular hole surgery are obvious. In addition to the appearance changes like DONFL and CMDS, the macular ganglion cell complex (mGCC) is also involved. (Chin J Ophthalmol, 2019, 55:747-756).

P1801Multiple members with an isolated atrial septal defect phenomenon presented in a family with Holt-Oram syndrome

Background

Holt-Oram syndrome (HOS), characterized by upper limb malformations, congenital heart diseases (CHD) and/or cardiac conduction abnormalities, is an autosomal dominant disease. Almost all the HOS patients suffer from cardiac and limb abnormalities at the same time. Among them, atrial septal defect (ASD) is the most common cardiac anomaly. The unusual phenotype in a pedigree including multiple members with isolated ASD and a few with isolated limb deformity attracted attention.

Aim

To detect mutant genes of ASD in this pedigree and make a definitive diagnosis. To investigate the mutant type of the gene and illustrate the possible mechanism of heterogeneous phenotype.

Methods

Echocardiography, electrocardiography and physical examination were given to a four-generation Chinese HOS family. Of all 11 patients in this pedigree, eight patients had isolated ASD and one patient had isolated finger deformity. In addition, two patients suffered from both diseases (Figure. 1). Whole Exome Sequencing was performed on the proband and his relatives including three with ASD only, one with finger deformity only and one normal person. Sanger sequencing was performed on biological relatives in this pedigree to valid rare variants. Single nucleotide polymorphisms and insertions/deletions were identified using the GATK program. Pathogenicity was predicted in software like SIFT, Ployphen-2, MutationTaster and CADD_phred.

Results

An exon site mutation (c.100dupG:p.Ala34fs) of TBX5 was detected in all the patients of this pedigree. This mutation site is located in front of T-box and most probably leads to haploinsufficiency of TBX5 protein. In addition, only 42 variants (1 splicing single nucleotide variants (SNV), 15 insertions/deletions, 24 nonsynonymous SNVs, 1 stopgain SNVs and 1 unknown) were found in 29 genes, which are related to cardiac disease.

Figure 1

Conclusions

Our study revealed a mutation (c.100dupG:p.Ala34fs) of TBX5 and further demonstrated the possibility of HOS-related TBX5 mutation in patients with congenital ASD only. This study clarified the diagnosis of this pedigree, provided genetic counseling and promoted the prevention and treatment of HOS. Further research is needed on mechanisms that may lead to phenotypic variation between and within families, such as random monoallelic expression.

Acknowledgement/Funding

None

Nurse and midwife researcher collaboration in eastern sub-Saharan Africa: a social network analysis

AIM

To investigate the collaborative networks among expert clinical nurse and midwifery researchers in eastern and southern Africa.

METHODS

Thirty-eight clinical nurse and midwifery researchers completed an online survey to analyse collaboration between respondents. Data were analysed using social network analysis, generating a network map and associated measurements.

RESULTS

Regional collaboration was poor. Those links that did exist centred on geographic proximity and participation in regional and international organizations.

CONCLUSION

These results help us to understand better ways to strengthen and support nursing and midwifery clinical research in eastern and southern Africa.

IMPLICATIONS FOR NURSING POLICY

Clinical nursing and midwifery research capacity building efforts should focus on supporting collaboration networks among individuals and institutions in the region.