Periodontal Inflammation Primes the Systemic Innate Immune Response

The presence of periodontal diseases (PDs) often strongly correlates with other severe chronic inflammatory conditions, including cardiovascular disease, diabetes, and arthritis. However, the mechanisms through which these diseases interact are unclear. In PD, tissue and bone destruction in the mouth is driven by elevated recruitment of polymorphonuclear neutrophils (PMNs), which are primed and recruited from the circulation to sites of inflammation. We predicted that systemic effects on PMN mobilization or priming could account for the interaction between PD and other inflammatory conditions. We tested this using a mouse model of ligature-induced PD and found elevated PMN counts specifically in bone marrow, supporting a systemic effect of periodontal tissue inflammation on PMN production. In contrast, mice with induced peritonitis had elevated PMN counts in the blood, peritoneum, and colon. These elevated counts were further significantly increased when acute peritonitis was induced after ligature-induced PD in mice, revealing a synergistic effect of multiple inflammatory events on PMN levels. Flow cytometric analysis of CD marker expression revealed enhanced priming of PMNs from mice with both PD and peritonitis compared to mice with peritonitis alone. Thus, systemic factors associated with PD produce hyperinflammatory PMN responses during a secondary infection. To analyze this systemic effect in humans, we induced gingival inflammation in volunteers and also found significantly increased activation of blood PMNs in response to ex vivo stimulation, which reverted to normal following resolution of gingivitis. Together, these results demonstrate that periodontal tissue inflammation has systemic effects that predispose toward an exacerbated innate immune response. This indicates that peripheral PMNs can respond synergistically to simultaneous and remote inflammatory triggers and therefore contribute to the interaction between PD and other inflammatory conditions. This suggests larger implications of PD beyond oral health and reveals potential new approaches for treating systemic inflammatory diseases that interact with PD.

Advances in SARS-CoV-2: a systematic review

OBJECTIVE

In December 2019, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection broke out in Wuhan, China. However, we still lack a comprehensive understanding of this emerging virus. In this manuscript, we collected relevant articles and reviewed the characteristics about SARS-CoV-2.

MATERIALS AND METHODS

We performed an online search on PubMed and Web of Science with the keywords COVID-19, 2019-nCoV and SARS-CoV-2, and summarized the epidemiology, virology, clinical features and treatments of SARS-CoV-2 infection.

RESULTS

We retrieved 157 published papers about SARS-CoV-2 from January, 2020 to April, 2020. We found that SARS-CoV-2 was a kind of virus with low mortality rate and high infectivity. This virus can enter human cells through angiotensin-converting enzyme 2 (ACE2) in alveoli and activate immune response in human body. SARS-CoV-2 infection can be classified as asymptomatic, mild, common, severe, and critical. We summarized antiviral drugs against SARS-CoV-2, such as remdesivir, hydroxychloroquine and favipiravir. Because the vaccine of SARS-CoV-2 is developing, more clinical studies are needed to verify the safety and efficacy of these treatments.

CONCLUSIONS

SARS-CoV-2 is a novel coronavirus that has caused a global pandemic. We should pay more attention to prevent SARS-CoV-2 and try to control it sooner.

[Current status of the clinical practice and analysis on the ratioanl prescription of antiarrhythmic drugs in Chinese patients with atrial fibrillation: Results from the Chinese Atrial Fibrillation Registry (CAFR) trial]

Objective: To explore the practice patterns and the related factors of oral antiarrhythmic drug (AAD) treatment in Chinese patients with atrial fibrillation (AF), and to evaluate the compliance of AAD application to atrial fibrillation management guidelines. Methods: From August 2011 to August 2016, medical records from 18 014 patients with AF were analyzed based on data from the Chinese Atrial Fibrillation Registry trial. Patients were divided into AAD group (7 788 cases, 43.23%) and non-AAD group (10 226 cases, 56.77%) according to whether AAD was used at baseline or at the time of first use during follow-up. Amiodarone (4 129 cases, 53.02%) and propafenone (3 211 cases, 41.23%) were the mostly prescribed AAD and subgroup analysis was performed accordingly. Medical records were analyzed by random forest regression to evaluate the use of AAD and related factors in patients with AF, and the rationality of AAD was analyzed according to the guidelines for the management of atrial fibrillation. Result: A total of 18 014 patients were included in this study, of which 60.48% (10 895/18 014) were male patients, 22.65% (4 081/18 014) were elderly patients(≥75 years old), there were 7 788 patients (43.23%) in AAD group, and 10 226 patients(56.77%) in non-AAD group. Compared with the non-AAD group, the elderly patients (≥75 years old, 13.74%(1 070/7 788) vs. 29.44%(3 011/10 226)), persistent AF (28.95% (2 250/7 788) 45.80% (4 683/10 226)), heart failure(8.29% (646/7 788) vs. 21.95% (2 245/10 226)), stroke and (or) TIA(12.15% (946/7 788) vs. 19.95% (2 040/10 226)), renal dysfunction(16.36%(1 274/7 788) vs. 29.37% (3 003/10 226)), and high thromboembolism risk(60.17% (4 748/7 788) vs. 76.40% (7 813/10 226)) were less prevalent in the AAD subgroup (P<0.001). Multivariate analysis showed that patients in tertiary hospitals (OR=3.72, 95%CI 3.17-4.37) were more likely to use AAD, elderly patients (≥75 years old, OR=0.47, 95%CI 0.39-0.55), persistent atrial fibrillation (OR=0.66, 95%CI 0.60-0.72), and patients with heart failure (OR=0.54, 95%CI 0.47-0.63), stroke and (or) TIA (OR=0.77, 95%CI 0.68-0.87), renal dysfunction (OR=0.75, 95%CI 0.59-0.95) and high thromboembolism risk(OR=0.7, 95%CI 0.58-0.84) were more likely not to use AAD(P<0.05). In the AAD group, amiodarone and propafenone were the most commonly used AAD, accounting for 53.02% (4 129/7 788) and 41.23% (3 211/7 788), respectively. Multivariate analysis showed that patients with persistent atrial fibrillation (OR=4.57, 95%CI 3.94-5.29) and coronary heart disease (OR=4.14, 95%CI 3.03-5.64), heart failure (OR=2.07, 95%CI 1.48-2.89), non-ischemic cardiomyopathy (OR=4.84, 95%CI 2.41-9.73) were more likely to use amiodarone, and those with normal left ventricular ejection fraction (OR=0.31, 95%CI 0.15-0.65) and low thromboembolism risk (OR=0.78, 95%CI 0.63-0.97) were more likely to use propafenone (P<0.001). The overall incidence of AAD treatment, which was not indicated by the guidelines was 6.5% (480/7 340); 5.1% (212/4 129) in the amiodarone group and 8.3% (268/3 211) in the propafenone group, respectively. Compared with the rational AAD use group, the proportion of irrational drug use was higher in the elderly (≥75 years old) (20.4% (98/480) vs. 12.9% (887/6 860)), patients of high thromboembolism risk (77.1% (379/480) vs. 59.0% (4 047/6 860)), and in non-tertiary hospitals (7.1% (34/480) vs. 3.3% (299/6 860)), but lower in men(50.8% (244/480) vs. 64.5% (4 427/6 860)), P<0.001. Conclusions: The patients with paroxysmal atrial fibrillation, who were treated with AAD, were mostly patients with fewer complications, and the patients who were treated with amiodarone were mostly patients with persistent atrial fibrillation, patients were more likely to complicate with organic heart disease. The incidence of AAD that do not comply with the guidelines was low, and it was more common in non-tertiary hospitals and the elder patients with high thromboembolism risk.

Low dose novel PARP-PI3K inhibition via nanoformulation improves colorectal cancer immunoradiotherapy

Multimodal therapy is often used in oncology to overcome dosing limitations and chemoresistance. Recently, combination immunoradiotherapy has shown great promise in a select subset of patients with colorectal cancer (CRC). Furthermore, molecularly targeted agents delivered in tandem with immunotherapy regimens have been suggested to improve treatment outcomes and expand the population of responding patients. In this study, radiation-sensitizing small molecules niraparib (PARP inhibitor) and HS-173 (PI3K inhibitor) are identified as a novel combination that synergistically enhance toxicity and induce immunogenic cell death both in vitro and in vivo in a CRC model. These inhibitors were co-encapsulated in a polymer micelle to overcome solubility limitations while minimizing off-target toxicity. Mice bearing syngeneic colorectal tumors (CT26) were administered these therapeutic micelles in combination with X-ray irradiation and anti-CTLA-4 immunotherapy. This combination led to enhanced efficacy demonstrated by improved tumor control and increased tumor infiltrating lymphocytes. This report represents the first investigation of DNA damage repair inhibition combined with radiation to potentiate anti-CTLA-4 immunotherapy in a CRC model.

[Clinical analysis of 150 cases of 2019 novel coronavirus infection in Nanyang City, Henan Province]

Objective: To analyze the epidemiological characteristics and clinical features of the patients with 2019-nCoV infection in Nanyang City, so as to provide evidence for clinical diagnosis and treatment. Methods: The epidemiology, clinical symptoms, atory and radiologic data of 150 patients with 2019-nCoV infection admitted to the designated hospitals in Nanyang City from January 24,2020 to February 16, 2020 were retrospectively analyzed. Results: The 150 patients with 2019 nCov infection consisted of 67 men and 83 women, and the median age was (45±16) years; 69 of them were the first generation case,60 of them were the second generation case, 6 of them were the third generation case,the median incubation period of the first generation case was (5.4±2.2) days, and the second generation case was (6.7±3.1) days, and the first-generation cases are the majority in severe patients (69%) . The most common basic disease was hypertension (13 cases, 9%), diabetes (9 cases, 6%), and the most common symptom is fever(142 cases, 95%, 63% showed moderate fever) , cough and sputum(108 cases,72%), fatigue(23 cases,15%), anorexia(20 cases, 13%), headache, diarrhea, muscle soreness, sore throat as the first symptoms. The average time from onset of symptoms to consultation was (4.2±2.2) days for all patients. The changes in peripheral blood cells were mainly lymphonpenia (83 cases, 55%) and eosinophilia (95 cases, 63%), The lymphocyte count of the severe and critically ill patients was more significantly reduced, and some patients had increased myocardial enzymes, mainly LDH (47 cases, 31%), and a few patients had liver function damage, mainly manifested in ALT and AST. High, very few patients have renal impairment. Among the inflammation-related indicators, the main manifestations are increased CRP (66 cases, 43%) and ESR (86 cases, 57%), elevated D-Dimer in 29% of patients. 144 cases have different degrees of infective lesions in chest CT examination, with 30 cases (21%) on one side and 144 cases (79%) on both sides. Morphologically, most of the lesions were patchy ground glass lesions, which could be accompanied by air bronchus signs and some consolidation and paving stone signs. Of the cases showing "white lung", 87% were sever ill or critically ill. After active treatment, 45% of patients were discharged according to discharge standards. 33% of sever and critically ill patients were discharged, 49% of them were degraded hospitalization.The average length of hospitalization was (12±4) days. Conclusion: A history of epidemiological exposure, fever, chest CT with signs of pneumonia, normal or decreased WBC, and lymphocytopenia, eosinophilia are the clinical basis for the diagnosis of this disease, and most of the sever patients were the first generation cases. The degree of lymphocytopenia is related to the severity of the disease.

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.

[Progress on clinical trials of cancer drugs in China, 2019]

Objective: To deliver macro understanding of the latest research progress on clinical trials and approved products of cancer drugs in China in 2019. Methods: The number of clinical trials and related investigational products by domestic and foreign enterprises in 2019 were acquired in the China Food and Drug Administration Registration and Information Disclosure Platform for Drug Clinical Studies, while listed drugs were obtained in the China Food and Drug Administration Query System for Domestic and Imported Drug. Characteristics on stage, scope, indication of those trials, classification and mechanism of involved products, as well as listed anticancer drugs were summarized and depicted. Results: There were 474 cancer drug trials registered in China in 2019, accounting for 21.8% of the total, and 397 (83.8%) were initiated by domestic pharmaceutical enterprises. Overall, international multicenter trials accounted for 13.1%, and phase I trials accounted for 47.3%. Compared with global enterprises, the proportion of international multi-center trials initiated by domestic companies is lower (4.8% vs. 55.8%, P<0.001), and the proportion of phase I clinical trials and bioequivalence trials is higher (51.9% vs. 23.4%, 19.4% vs. 1.3%, P<0.001). An accumulative of 27 cancer types were involved for all the cancer drug trials, and lung cancer, solid tumor, and breast cancer were the most common cancer types, with 103, 95 and 49 trials, respectively. For the three cancer types unique to Chinese population, gastric, liver and esophageal cancer, the total number of initiated trials was 47. For all those trials, there were 335 cancer drug varieties, with 86.0% developed by domestic pharmaceutical enterprises, including 300 therapeutic drugs, 30 adjunctive drugs and 5 preventive drugs. In terms of mechanism, targeted drugs and immune drugs were the most popular, accounting for 74.6% and 20.3%, respectively. In addition, 17 anticancer drugs targeting on 11 cancer types were approved in China in 2019. Conclusions: Clinical trials on cancer drugs in China have ushered a booming era, with large number of innovative agents represented by targeted drugs and immune drugs under clinical development or putting into clinical practice. Those local enterprises are playing more and more critical roles. Strengthening clinical research and development on Chinese unique cancer types is the key direction of future work.

[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.

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