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This study developed a new single-tube multiplex real-time PCR method for detecting toxigenic C. difficile directly from fecal samples using tcdA, tcdB, cdtB, and internal gene tpi as targets, which could be performed on kinds of polymerase chain reaction device including point-of-care testing (POCT), with improved detection efficiency. The specificity, sensitivity, and repeatability of each gene was evaluated using 69 C. difficile isolates and 74 fecal samples. Results were compared with established PCR, qPCR, and ELISA methods. Interspecies specificity was 100% based on six common intestinal pathogens (Escherichia coli, Enterococcus Faecium, Enterococcus faecalis, Clostridium perfringens, Bacteroides fragilis, Clostridium botulinum). The lower detection limit (LDL) for tcdA, tcdB, and cdtB with pure C. difficile DNA was 101,100, and 100 copies/μL, respectively, the coefficients of variation among different experimental batches and within each experimental batch were both less than 3%, which shows that this method has strong repeatability. And the LDL of fecal DNA was 5 × 100, 5 × 103, and 5 × 102 colony-forming units (CFU)/g, respectively. In addition, the efficiency for detection of tcdA was compared with established PCR and real-time PCR methods, demonstrating high consistency (98.4%) and similar sensitivity. ELISA was used to confirm inconsistent results, which were identical with our method. The sensitivity and specificity for detecting toxigenic C. difficile in fecal samples were 96.49% and 94.12% compared with the toxigenic culture (TC). This method effectively identified the toxigenic and non-toxigenic strains with high specificity, sensitivity, and repeatability, and could reduce the false positive rate of tcdA, and accurately identify the typical Asian strain RT017, making it potentially contribute to the surveillance of CDI in China.

Objective To evaluate the outcomes of cervical spondylotic radiculopathy secondary to bony foraminal stenosis treated with anterior cervical discectomy and fusion (ACDF) combined with anterior cervical foraminotomy (ACF) assisted by High‐Definition 3‐Dimensional Exoscope. Methods In this retrospective study, a total of 19 consecutive patients (12 males and seven females, with an average of 49.2 years, range from 40 to 59 years) with spondylotic radiculopathy caused by bony foraminal stenosis underwent ACDF combined with ACF assisted by High‐Definition 3‐Dimensional Exoscope in our hospital between January 2019 and December 2019 were included in this study. All patients signed the consent form before the surgery. The patient baseline information such as gender, age, body mass index (BMI), surgery time, blood loss, hospital stay, lesion segment, side, follow‐up time and postoperative complications were recorded. The Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and Visual Analogue Scale (VAS) were measured and compared before surgery, 1 months and final follow‐up after surgery. The radiographic outcomes were evaluated using the C2‐C7 angel, disc height, foraminal height, superior diagonal distance, inferior diagonal distance, and foraminal area. Results The involved levels included C4‐C5 (six cases), C5‐C6 (10 cases), C6‐C7 (three cases). The mean duration of the surgery, mean blood loss, mean hospital stay, and mean follow‐up were 100 ± 11.10 min, 19.4 ± 7.05 mL, 7.1 ± 0.99 days, and 12.1 ± 2.25 months, respectively. The average preoperative JOA score was 11.9 ± 1.31, then improved to 15.7 ± 0.73 (t = −13.45, P, ACDF combined with ACF assisted by High‐Definition 3‐Dimensional Exoscope is an effective and safe for the treatment of CSR caused by secondary to bony foraminal stenosis. In addition to sufficient decompression, this technique can also significantly reduce intraoperative bleeding.

Autism spectrum disorders (ASDs) are highly associated with oxidative stress. We have recently shown that Disconnected-interacting protein homolog 2 A (DIP2A) functions in ASD pathophysiology by regulating cortactin acetylation for spine development and synaptic transmission. However, its role is not fully understood in the context of its abundant expression in mitochondria. In this paper, we found that DIP2A was involved in superoxide dismutase (SOD)-mediated antioxidative reactions. In mice, DIP2A knockout inhibited SOD activity and increased reactive oxygen species (ROS) levels in the cerebral cortex. In vitro gain-of-function experiments further confirmed the positive role of DIP2A in scavenging ROS upon oxidative stress. Moreover, DIP2A knockout caused irregular mitochondrial morphology in the cerebral cortex and impaired mitochondrial metabolism with an over consumption of lipids for energy supply. Taken together, these results revealed unrecognized functions of DIP2A in antioxidative protection, providing another possible explanation for DIP2A-mediated ASD pathophysiology.

Background Ankylosing spondylitis with Andersson lesions is not rare, but its potential pathogenesis and natural course remain unclear. Case description We describe a case of CT image changes in ankylosing spondylitis from fracture to Andersson lesions. A 40-year-old man with a 23-year history of ankylosing spondylitis presented with acute back pain after a slight fall, and the CT showed a T12 fracture; the patient refused surgery for 12 months. The process from fracture to Andersson lesions was characterized by CT, including the subsequent interbody bone graft with internal fixation and successful bone fusion at the last follow-up. Histopathologic analysis showed degenerative fibrocartilage tissue calcification, necrotic intervertebral disc tissue, fibrovascular hyperplasia, and focal accumulation of inflammatory cells. Conclusion Aseptic inflammation and persistent instability caused by a fracture contributed in the course from fracture to Andersson lesions in ankylosing spondylitis. CT can accurately track the pathological process, and interbody fusion via the posterior pedicle lateral approach can achieve satisfactory effectiveness, good fusion and kyphosis correction.

Clostridioides difficile is the predominant pathogen responsible for antimicrobial associated diarrhea (AAD) and health care facility-associated infectious diarrhea. The role of C. difficile in China and its impact on public health have gained attention in recent years. Most clinical C. difficile isolates in China belong to multilocus sequence type clade 1 with sequence types (STs) 3, 35 and 54 predominating. Of note, the proportion of C. difficile isolates from clade 4, especially ST37 (PCR ribotype 17), is much higher in China than in other areas. In China, the antimicrobial-resistance profile of C. difficile is similar to that of other countries, demonstrating a higher resistance rate to erythromycin, clindamycin, and fluoroquinolones (ciprofloxacin, levofloxacin, and moxifloxacin). In general, susceptibility to vancomycin and metronidazole of clinical C. difficile in China is high, however, some resistance to metronidazole have recently been reported. Preclinical research on C. difficile in animals in China is limited, and different studies have reported varied isolation rates and antimicrobial resistance profiles. The diverse molecular types of C. difficile in China merit further epidemiological, genomic and evolutionary investigation. While the use of probiotics in preventing C. difficile infection (CDI) have received both support and opposition, the discovery of new probiotics and new formulations are showing promising results in combating the threat posed by CDI.

Background Kummell disease combined with huge spinal epidural hematoma is a very rare phenomenon, and its potential pathogenesis and natural course remain unclear.Case description We describe a rare case of Kummell disease with huge spinal epidural hematoma. A 75-year-old male was diagnosed with osteoporotic vertebral compression fractures and was treated conservatively. After suffering minor trauma again 8 days ago, he presented unbearable low back pain and activity restriction. Lumbar MRI showed that L1 vertebral had re-fracture and intervertebral vacuum cleft, and a huge spinal epidural hematoma extending from T12- L1. Due to the patient had no neurological deficits and unbearable low back pain, percutaneous vertebroplasty was performed, and pain was relieved significantly. The follow-up MRI showed that the hematoma almost disappeared 7 days after the operation.Conclusion Although extremely rare, there is a possibility of spinal epidural hematoma after re-fracture of Kummell disease, and it could be further confirmed via MRI and pathological examination. Timely operation is recommended, and the results are usually favorable.

Two new platinum(II) complexes 7a and 7b with methyl hydrazinecarbodithioate derivatives of indolin-2-one have been prepared and characterized by single-crystal X-ray diffraction, NMR spectroscopy and mass spectrometry. Antiproliferative activity of the two complexes and their ligands 6a and 6b against HCT-116, MCF-7 and MDA-MB-231 cell lines was determined by the MTS assay. Complexes 7a and 7b exhibited stronger antiproliferative activity against three cell lines than compounds 6a and 6b (IC50, 1.89-5.60 versus 6.52-35.13 μM). Moreover, treatment of HCT-116 cells with the complexes resulted in an obvious sub-G1 peak by cell cycle profile analysis, and an increase of cleaved PARP1 and caspases 3, 7, and 9 by immunoblotting analysis. Live cell imaging showed that nucleus shrinkage and condensation started to appear when MCF-7 cells were treated with 7a for 8 h. Fluorescent spectrophotometric analysis revealed that the complexes physically associated with calf thymus DNA. Competitive DNA binding assays uncovered that the complexes non-covalently bind to DNA. Taken together, our results indicated that the two new platinum(II) complexes 7a and 7b non-covalently bind to DNA with high affinity and exhibit cytotoxicity against cancer cells by inducing apoptosis.

To further enhance oil recovery in reservoir after chemical flooding, an efficient activator formulation for promoting metabolism of endogenous microorganism was researched. Changes in community structure, growth and metabolites of endogenous microorganism were analyzed by methods of aerogenic experiments, physical simulation experiments, electron microscopy scanning (SEM), T-RFLP and Pyrophosphate sequencing. To evaluate whether endogenous microorganism activator screened in laboratory could activate endogenous microorganisms and enhance oil recovery in reservoirs after polymer flooding. The flooding effect and mechanism were studied, and this activator was used in a testing well group in Daqing oilfield. The results of the aerogenic experiments showed that the activator could activate the endogenous microorganisms in the injected water and make them produce a lot of biogas. The pressurized gas reached 2MPa after 60d static culture of activator in a high pressure vessel. The results showed that the activator could activate the endogenous microorganisms in the injected sewage and make them have a lot of growth and reproduction in the core and physical simulation of natural core flooding experiment. In the field test,the incremental oil production was 5957 t while the water content declined by 2.2% after injecting the activator, which provides an effective way to further enhance oil recovery in reservoir after chemical flooding.

Laboratory evaluation showed that rhamnolipid combined displacement system with low and wide effective concentration (0.125%~1.0%) can reduce interfacial tension with Pubei oil and water to 10-2mN/m. Injection of 0.5PV of rhamnolipid combined displacement system in natural core simulating reservoir permeability can increase recovery by 7.9%~9.3% more than water flooding. Field test for rhamnolipid combined displacement system was carried out with 2 injectors and 9 producers. Alternating injection is performed with two slugs with total volume of 19895.5m3, containing 250.9t of dosage. During 13 months of field test, stageous cumulative incremental oil production was 2014t, with 224t of average single well incremental oil. Daily oil production increased from 1.5t/d to 1.85t/d, average water cut decreased by1.5%, and input-output ratio was 1:2.4. This study provided a new way to improve oil recovery for other similar water flooded reservoirs.