OBJECTIVEThis study aims to evaluate the effect of ptxA and ptxB genes, which are important genes in the L-ascorbate phosphotransferase system (PTS) of Streptococcus mutans (S. mutans).

METHODSThe ptxA-, ptxB-, and ptxAB-double deficient mutant as well as ptxAB-complemented strain were constructed. Quantitative real-time polymerase chain reaction analysis was performed to evaluate the expression of the target genes of wild-type S. mutans when L-ascorbate was used as the sole carbohydrate source. The OD₆₀₀ values of the wild type, deficient, and complemented strains were continuously monitored, and their growth curves were constructed to compare growth capacity.

RESULTSPolymerase chain reaction and sequencing analyses suggested that deficient and complemented strains were successfully constructed. The expression levelsof ptxA and ptxB significantly increased (P < 0.01) when L-ascorbate was used as the sole carbohydrate source. The growth capacity of the deficient mutants decreased compared with that of the wild-type strain. However, the wild-type phenotype could be restored in the complemented strain.

CONCLUSIONptxA and ptxB genes are associated with L-ascorbate metabolism of S. mutans. The construction of deficient strains and complemented strain lay a foundation for further mechanism study on L-ascorbate metabolism in S. mutans.

Bacterial Proteins ; genetics ; Genes, Bacterial ; Phosphotransferases ; metabolism ; Real-Time Polymerase Chain Reaction ; Streptococcus mutans ; physiology ; Transcription Factors ; genetics

Objective To study the clinical characteristics and potential influencing factors of rehabilitation of cognition in post-stroke patients with aphasia.methods Forty-one patients with aphasia after ischemic stroke,admitted to Nanfang hospital and Nanfang Yanling Hospital from June 2015 to November 2016 were included.Their primary clinical information and NIHSS scores were registered.In acute phase,Aphasia Battery of Chinese and Boston Diagnostic Aphasia Examination was used to evaluate language ability and classify the aphasia type.Non-language-based Cognitive assessment (NLCA) was used to assess patients' nonlinguistic cognition.Besides,the assessment of post-stroke depression and dependence degree of daily living activities were performed.3 months later,patients were evaluated again.A total of 30 aphasia patients completed the final follow-up.Result s(1) Compared with the baseline in patients with aphasia after stoke,all domains of language ability were significantly improved after 3 months(P<0.05).(2)Every nonlinguistic cognitive score was significantly increased within 3 months(total NLCA score(65.83±13.02 vs 48.00±25.11),memory(17.23±2.49 vs 13.30±5.42),visual spatial ability(10.67±2.43 vs 8.07±3.75),logical reasoning ability(6.53±1.48 vs 4.97±2.43),attention(25.57±5.79 vs 17.43±12.33),executive function(5.77±3.47 vs 4.20±4.23),all P<0.01).(3)The NLCA total score (62.40±14.23 vs 72.70±6.34)and scores in visual spatial (9.95±2.67 vs 12.10±0.74)and abstract reasoning(6.05±1.54 vs 7.50±0.71) of persisting aphasia patients were significantly lower than that of aphasia recovered group(all P<0.05).(4) Multivariate regression showed that initial NLCA score had a negative predictive effect on cognitive function improvement of aphasia patients 3 months after stroke(β=-0.603,P<0.01).Conclusion The rehabilitation of cognitive function in patients with aphasia after stroke is similar to that of language function.Patients with persisting aphasia may have worse performance on nonlinguistic cognition and ability of daily living,even with more serious depressive emotion.Evaluation of nonlinguistic cognition in post-stroke aphasia patients in acute phase is necessary and the score seems to be an important predicting factor of 3-month cognition.

OBJECTIVETo test whether Porphyromonas gingivalis (P. gingivalis) could produce bacterial signal molecule, bis-(3'-5')-cyclic dimeric adenosine monophosphate (c-di-AMP) and lay the foundation for explorations of its roles in life metabolism and periodontitis immunity of P. gingivalis.

METHODSP. gingivalis standard strain ATCC33277 was used as the experimental strain to extract nucleic acids from the bacteria. Then, c-di-AMP was detected using high performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS). Subsequently, HPLC was used to validate the sample further.

RESULTSBased on the signal/noise (S/N) for 3 : 1, the limit of determination of HPLC-MS/MS for peak time of c-di-AMP standard substances was 7.49 min and nucleic acid extractions from P. gingivalis was 8.82 min (S/N > 3). Further confirmation of HPLC showed that nucleic acid extractions from both P. gingivalis and c-di-AMP standard substances pre- sented goal absorbent peaks at 15.7 min, with the same ultraviolet absorbent spectrum.

CONCLUSIONThe nucleic acid extrac- tions from P. gingivalis contained c-di-AMP, which shows that P. gingivalis could produce c-di-AMP.

Chromatography, High Pressure Liquid ; Cyclic AMP ; chemistry ; metabolism ; Periodontitis ; Porphyromonas gingivalis ; metabolism ; Tandem Mass Spectrometry

Objective To analyze the effect of spousal synchronous exercise and diet intervention on maternal and neonatal outcomes in overweight pregnant women with gestational diabetes mellitus(GDM).Methods We divided 120 overweight pregnant women with GDM into intervention and control groups(n= 60 per group),who received spousal synchronous and routine exercise and diet interventions,respectively.The age,body mass index(BMI),and levels of fasting blood glucose(FPG),2-hour postprandial blood glucose(2 h-PG),and glycosylated hemoglobin(HbA1c)at the first prenatal examination were recorded.The levels of FPG,2 h-PG,and HbA1c at the diagnosis of GDM and gestational week 28,delivery mode,and incidence of complications during the delivery were compared between the groups.The self-rating depression scale and self-rating anxiety scale were used to evaluate the women's mental status after delivery.The body weight,blood glucose level,Apgar score,and incidence of complications including macrosomia,hypoglycemia,and asphyxia in the new-borns were compared between the groups.Results The groups did not differ significantly in term of age,BMI,FPG,2 h-FPG,or HbA1c at GDM diagnosis(P>0.05).At gestational week 28,the FPG,2 h-FPG,and HbA1c levels were significantly lower than those before the intervention in both groups,and were also significantly lower in the intervention group than in the control group(P<0.05).Com-pared with the control group,the proportion of natural delivery was significantly higher and the incidence of complications was sig-nificantly lower in the intervention group(P<0.05).The anxiety and depression status were significantly better in the intervention group than in the control group(P<0.05).Compared with the control group,the frequency of macrosomia and blood glucose levels were significantly lower and the Apgar scores were significantly higher in the intervention group(P<0.05).Conclusion Spousal synchronous exercise and diet intervention may effectively decrease the blood glucose and HbA1c levels in overweight pregnant women with GDM,decrease the incidence of maternal and neonatal complications,and improve pregnant women's mental status.

Objective To explore the effect of brain-derived neurotrophic factor (BDNF) on brain damage and its mechanism by investigating the influence of exogenous BDNF on mitochondrial membrane potential (△ψm) and cytochrome C (cytC) release in the hippocampus after status convulsivus (SC).Methods Sixty-four healthy adult Wistar rats were randomly divided into normal group (n=32) and SC group (n=32) which were injected with lithium-pilocarpine intraperitoneally for SC continuing 30 min.The rats in these two groups were intraventricularly injected (Ⅳ) with normal sodium (NS) 2 μL,BDNF 4 μL (0.1 μg/μL),or BDNF antibody 2 μL (200 μg/mL) in left lateral ventricle (or no injection),and sacrificed 6 h later.The levels of △ψm and cytC ofhippocampal cells were determined by flow cytometry.Results (1) As compared with subgroups of normal group,the levels of △ψm significantly decreased and cytC significantly increased in the SC subgroups,respectively (P＜0.05).(2) In normal group,the levels of △ ψm significantly decreased and cytC significantly increased in the lateral hippocampus of normal-anti-BDNF subgroup as compared with those in normal-non-Ⅳ subgroup (P＜ 0.05),and the levels of △ψm was significantly higher and cytC significantly lower in the lateral of normal-BDNF subgroup than those in the lateral ofnormal-anti-BDNF subgroup (P＜0.05).(3) In SC group,as compared with those in the lateral of SC-NS subgroup and SC-non-Ⅳ subgroup,the level of △ψm significantly decreased and cytC level significantly increased in the lateral of SC-anti-BDNF subgroup (P＜0.05),however they were reversed in the lateral of SC-BDNF subgroup (P＜0.05).Conclusions SC could induce △ψm decrease and cytC release ofhippocampal cells.The exogenous BDNF could partly inhibit the decrease of △ψm and the release of cytC in the lateral hippocampus after SC,which indicates that BDNF might protect the brain after SC through inhibiting the early event of apoptosis.

Accurate segmentation of ground glass nodule (GGN) is important in clinical. But it is a tough work to segment the GGN, as the GGN in the computed tomography images show blur boundary, irregular shape, and uneven intensity. This paper aims to segment GGN by proposing a fully convolutional residual network, i.e., residual network based on atrous spatial pyramid pooling structure and attention mechanism (ResAANet). The network uses atrous spatial pyramid pooling (ASPP) structure to expand the feature map receptive field and extract more sufficient features, and utilizes attention mechanism, residual connection, long skip connection to fully retain sensitive features, which is extracted by the convolutional layer. First, we employ 565 GGN provided by Shanghai Chest Hospital to train and validate ResAANet, so as to obtain a stable model. Then, two groups of data selected from clinical examinations (84 GGN) and lung image database consortium (LIDC) dataset (145 GGN) were employed to validate and evaluate the performance of the proposed method. Finally, we apply the best threshold method to remove false positive regions and obtain optimized results. The average dice similarity coefficient (DSC) of the proposed algorithm on the clinical dataset and LIDC dataset reached 83.46%, 83.26% respectively, the average Jaccard index (IoU) reached 72.39%, 71.56% respectively, and the speed of segmentation reached 0.1 seconds per image. Comparing with other reported methods, our new method could segment GGN accurately, quickly and robustly. It could provide doctors with important information such as nodule size or density, which assist doctors in subsequent diagnosis and treatment.
Algorithms ; China ; Disease Progression ; Humans ; Multiple Pulmonary Nodules ; Neural Networks, Computer ; Tomography, X-Ray Computed/methods*

In the USA, there were about 1 ‍806 ‍590 new cancer cases in 2020, and 606 520 cancer deaths are expected to have occurred in 2021. Lung cancer has become the leading cause of death from cancer in both men and women (Siegel et al., 2020). Clinical studies show that the five-year survival rate of lung cancer patients after early diagnosis and treatment intervention can reach 80%, compared with that of patients having advanced lung cancer. Thus, the early diagnosis of lung cancer is a key factor to reduce mortality.
Male ; Humans ; Female ; Tomography, X-Ray Computed/methods* ; Algorithms ; Lung Neoplasms/pathology* ; Cluster Analysis

BACKGROUND: The effect of arteriosclerotic intracranial arterial vessel wall enhancement (IAVWE) on downstream collateral flow found in vessel wall imaging (VWI) is not clear. Regardless of the mechanism underlying IAVWE on VWI, damage to the patient's nervous system caused by IAVWE is likely achieved by affecting downstream cerebral blood flow. The present study aimed to investigate the effect of arteriosclerotic IAVWE on downstream collateral flow. METHODS: The present study recruited 63 consecutive patients at the Second Hospital of Hebei Medical University from January 2021 to November 2021 with underlying atherosclerotic diseases and unilateral middle cerebral artery (MCA) M1-segment stenosis who underwent an magnetic resonance scan within 3 days of symptom onset. The patients were divided into 4 groups according to IAVWE and the stenosis ratio (Group 1, n = 17; Group 2, n = 19; Group 3, n = 13; Group 4, n = 14), and downstream collateral flow was analyzed using three-dimensional pseudocontinuous arterial spin labeling (3D-pCASL) and RAPID software. The National Institutes of Health Stroke Scale (NIHSS) scores of the patients were also recorded. Two-factor multivariate analysis of variance using Pillai's trace was used as the main statistical method. RESULTS: No statistically significant difference was found in baseline demographic characteristics among the groups. IAVWE, but not the stenosis ratio, had a statistically significant significance on the late-arriving retrograde flow proportion (LARFP), hypoperfusion intensity ratio (HIR), and NIHSS scores ( F = 20.941, P <0.001, Pillai's trace statistic = 0.567). The between-subject effects test showed that IAVWE had a significant effect on the three dependent variables: LARFP ( R2 = 0.088, F = 10.899, P = 0.002), HIR ( R2 = 0.234, F = 29.354, P <0.001), and NIHSS ( R2 = 114.339, F = 33.338, P <0.001). CONCLUSIONS: Arteriosclerotic IAVWE significantly reduced downstream collateral flow and affected relevant neurological deficits. It was an independent factor affecting downstream collateral flow and NIHSS scores, which should be a focus of future studies. TRIAL REGISTRATION ChiCTR.org.cn, ChiCTR2100053661.
Humans ; Constriction, Pathologic/pathology* ; Magnetic Resonance Imaging/methods* ; Middle Cerebral Artery/pathology* ; Tomography, X-Ray Computed