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.

Infrapatellar fat pad resection or preservation during total knee arthroplasty: a meta-analysis of randomized controlled trials

BACKGROUND

The infrapatellar fat pad (IPFP) or Hoffa's fat pad is often resected during total knee arthroplasty in order to improve visibility. However, the management of the IPFP during total knee arthroplasty (TKA) is the subject of an ongoing debate that has no clear consensus. The purpose of this review was to appraise if resection of the IPFP affects clinical outcomes.

METHODS

We conducted a meta-analysis to identify relevant randomized controlled trials involving infrapatellar fat pad resection and infrapatellar fat pad preservation during total knee arthroplasty in electronic databases, including Web of Science, Embase, PubMed, Cochrane Controlled Trials Register, Cochrane Library, Highwire, CBM, CNKI, VIP, and Wanfang database, up to March 2020.

RESULTS

Nine randomized controlled trials, involving 783 TKAs (722 patients), were included in the systematic review. Outcome measures included patellar tendon length (PTL), Insall-Salvati ratio (ISR), rate of anterior knee pain, Knee Society Scores (KSS), and knee range of motion. The meta-analysis identified a trend toward the shortening of the patellar tendon with IPFP resection at 6 months (P = 0.0001) and 1 year (P = 0.001). We found no statistical difference in ISR (P = 0.87), rate of anterior knee pain within 6 months (p = 0.45) and 1 year (p = 0.38), KSS at 1 year (p = 0.77), and knee range of motion within 6 months (p = 0.61) and 1 year (0.46).

CONCLUSION

Based on the available level I evidence, we were unable to conclude that one surgical technique of IPFP can definitively be considered superior over the other. More adequately powered and better-designed randomized controlled trial (RCT) studies with long-term follow-up are required to produce evidence-based guidelines regarding IPFP resection.

Preparation and characterization of a novel controlled-release nano-delivery system loaded with pyraclostrobin via high-pressure homogenization

BACKGROUND

The development of efficient and safe green pesticides is a scientific strategy to alleviate current pesticide residues, environmental pollution, and threats to non-target organisms. Pesticide controlled-release formulations (CRFs) have attracted wide attention because they can control the rate of release of active ingredients and prolong the effective duration. In particular, nanoscale pesticide sustained-release systems have excellent biological activity and distribution performance because of their small particle size. Some technical difficulties remain in obtaining nanoscale CRFs.

RESULTS

We successfully fabricated pyraclostrobin nanosphere CRF by combining high-pressure homogenization technology and emulsion-solvent evaporation methods. The pyraclostrobin nanospheres had a uniform spherical shape with a mean particle size of 450 nm and polydispersity index of less than 0.3. The pyraclostrobin loading capacity reached 53.6%, with excellent storage stability. The contact angle of nanospheres on cucumber leaf surfaces demonstrated that it had good wettability. Compared with pyraclostrobin technical and commercial formulations, the nanosphere systems showed a significantly sustained release of pyraclostrobin for longer (up to 250 h). A preliminary bioassay against Penicillium ochrochloron showed that the bioactivity and long-term efficiency of pyraclostrobin nanospheres were superior to those of the commercial formulation.

CONCLUSION

This research introduced a simple, fast, expandable method for preparing pyraclostrobin nanospheres. The results showed that pyraclostrobin nanospheres could prolong the duration of pesticide efficacy and enhance bioactivity. Furthermore, this technology provides a platform for scale-up production of nano-scale pesticide CRFs. © 2020 Society of Chemical Industry.

[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.

Construction and characterization of avermectin B2 solid nanodispersion

Poorly water-soluble pesticide compounds are difficult to be formulated as environmentally friendly formulations with high efficacy. For the conventional formulations, more than 50% of pesticides are lost during application due to the decomposition of active ingredient, dust drift and running off. Therefore, there is an urgent need to construct a novel formulation for improving the bioavailability of pesticides. The avermectin B2 solid nanodispersion was developed by self-emulsifying and solidification technology. The average particle size, surface tension and contact angle on cabbage leaves of the solid nanodispersion were 35.3 nm, 36.6 mN/m and 58°, respectively. The toxicities of the nanoformulation against diamondback moths and root-knot nematode were more than 1.7 times that of conventional emulsion in water and water dispersible granule. This investigation demonstrated that for foliage-applied pesticides, the formulation bioavailability had positive correlation with wettability which was negatively correlated with surface tension and contact angle. This study provides an easy and scalable technique to construct the effective and environmentally friendly nanoformulations. The toxicity improvement of the solid nanodispersion will significantly reduce dosage and environmental pollution of pesticide. The clarified relationship between formulation parameters and biological activity will contribute to the design and construction of novel pesticide formulations.

Is continuous catheter adductor canal block better than single-shot canal adductor canal block in primary total knee arthroplasty?: A GRADE analysis of the evidence through a systematic review and meta-analysis

BACKGROUND

The adductor canal block (ACB) has emerged as an alternative to the femoral nerve block (FNB) after total knee arthroplasty. This meta-analysis was conducted to investigate which ACB method provides better pain relief and functional recovery after total knee arthroplasty METHODS:: We conducted a meta-analysis to identify randomized controlled trials involving single-shot adductor canal block (SACB) and continuous catheter ACB (CACB) after TKA up to December 2019 by searching databases including the PubMed, Web of Science, Embase, Cochrane Controlled Trials Register, Cochrane Library, CBM, CNKI, VIP, and Wanfang databases. Finally, we included 8 randomized controlled trials involving 702 knees in our study. We used Review Manager Software and Grading of Recommendations Assessment, Development, and Evaluation profiler to perform the meta-analysis.

RESULTS

Compared with SACB, CACB can achieve better postoperative pain relief at 24 and 48 h both at rest and after mobilization, lower amount of opioid consumption at 72 h, a shorter length of hospital stay (LOH) and larger range of motion (ROM). In addition, the Timed Up and Go (TUG) test results; quadriceps strength; and incidence of complications, including postoperative nausea and vomiting, DVT, catheter-related infections, catheter dislodgement and neurologic deficits, showed no significant difference between the two ACB methods.

CONCLUSION

The results of this study demonstrate that CACB is an effective alternative to SACB and can provide better pain relief, a shorter LOH, more degrees of maximum flexion and a lower amount of opioid consumption over time, but it provides a comparable level of recovery of quadriceps strength and mobility with a similar risk of catheter-related complications. Thus, CACB may be a better analgesia strategy than SACB after TKA at present.

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.

Biocidal activity of polylactic acid-based nano-formulated abamectin on Acyrthosiphon pisum (Hemiptera: Aphididae) and the aphid predator Adalia bipunctata (Coleoptera: Coccinellidae)

Abamectin is a common biocide used to control agricultural insect pests. However, the water insolubility of abamectin may result in extra organic solvent introduced in the environment. To solve this issue, it is desirable to develop nanoformulations to encapsulate abamectin with environment-friendly polymers. In this study, two polylactic acid based abamectin nanoformulations were prepared. The average particle sizes, measured by dynamic light scattering and transmission electron microscope, were 240 nm and 150 nm, respectively. The insecticidal activity of these nano-formulated abamectin was examined in the laboratory on the pea aphid, Acyrthosiphon pisum (Hemiptera: Aphididae). The acute toxicity of nano-formulated abamectin on non-target aphid predator Adalia bipunctata (Coleoptera: Coccinellidae) was also evaluated by topical, residual and oral exposure. The two nano-formulated abamectin had comparable insecticidal effect with commercial abamectin formulation against the pea aphid. Taking median lethal concentration (LC50) as the toxicological endpoint, nanoformulations had higher contact toxicity and lower oral toxicity to first-instar larvae of the predator A. bipunctata. These results are expected to contribute to the application of solvent-free nano-formulated pesticides that comply with the integrated pest management (IPM) strategies.

Dual-Functionalized Pesticide Nanocapsule Delivery System with Improved Spreading Behavior and Enhanced Bioactivity

The prevention and control of pests and diseases are becoming increasingly difficult owing to extensive pesticide resistance. The synergistic use of pesticides for disease control is an effective way of slowing pesticide resistance, reducing the number of pesticide applications, and protecting the environment. In this study, a dual-functionalized pesticide nanocapsule delivery system loaded with two active ingredients (AIs)—validamycin and thifluzamide—was developed to prevent and control rice sheath blight; the nanocapsule system was based on a water–oil–water double emulsion method combined with high-pressure homogenization technology. Our results showed that the dual-functionalized pesticide nanocapsules were monodisperse spheres with a mean particle size of ~260 nm and had good storage stability. Compared with commercial formulations, the dual-functionalized pesticide nanocapsules exhibited good foliar spread owing to their small size, which is beneficial for reducing the loss of pesticides on the leaves. The 50% median effect concentration and synergistic ratio against Rhizoctonia solani of the dual-functionalized pesticide nanocapsules and commercial formulation were 0.0082 and 0.0350 μg/mL, and 2.088 and 0.917, respectively. These findings indicate that the bioactivity of the dual-functionalized system was significantly better than that of the commercial formulations and that the dual-functionalized system demonstrated a clear synergistic effect between the two AIs. The system presented here is simple, fast, and capable of dual-pesticide loading with significant synergistic effects. Our findings could help to facilitate the improvement of pesticides efficiency and the slowing of pesticide resistance.

[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