Chronic pontine strokes: Diffusion tensor imaging of corticospinal tract indicates the prognosis in terms of motor outcome.

OBJECTIVE: To investigate relationship between the diffusion indexes of corticospinal tract (CST) and the neurological motor outcomes in chronic pontine stroke patients. METHODS: Diffusion tensor imaging (DTI) is performed in 27 patients with chronic pontine stroke. Fractional anisotropy (FA) values along the CST area, the track number, and the CST length are measured. Neurological and motor outcomes are evaluated based on Fugl-meyer (FM), National Institutes of Health Stroke Scale (NIHSS), Barthel index (BI), and modified Rankin scale (mRS) scores. The relationships between FA ratios (rFAs) in the CST of stroke subjects and their clinical motor scores are analyzed through Spearman's correlation analysis. Then, diffusion tensor tractography (DTT) is performed to show the injury degree of CST. RESULTS: First, FA values are decreased in the infarct area, cerebral peduncle, posterior limb of the internal capsule, and precentral gyrus compared with those in the contralateral side. The number of CST is decreased in the ipsilateral side of the infarct. Second, rFAs in the cerebral peduncle, posterior limb of the internal capsule, and CST rnum correlate positively with FM scores (r = 0.824, 0.672, 0.651, p < 0.001) and negatively with mRS scores (r = -0.835, -0.604, -0.645, p≤0.001). Third, the injury degree of CST correlates negatively with FM scores (r = -0.627, p < 0.001). CONCLUSIONS: The study demonstrates that rFAs in the cerebral peduncle, posterior limb of the internal capsule, and CST rnum associate with motor outcome, suggesting that DTI may be applicable for outcome evaluation.

Co-circulation of coxsackieviruses A-6, A-10, and A-16 causes hand, foot, and mouth disease in Guangzhou city, China.

BACKGROUND: Hand, foot, and mouth disease (HFMD) is a common infectious disease occurring in children under 5 years of age worldwide, and Enterovirus A71 (EV-A71) and Coxsackievirus A16 (CVA-16) are identified as the predominant pathogens. In recent years, Coxsackievirus A6 (CVA-6) and Coxsackievirus A10 (CVA-10) have played more and more important role in a series of HFMD outbreaks. This study aimed to understand the epidemic characteristics associated with HFMD outbreak in Guangzhou, 2018. METHODS: The clinical and laboratory data of 1220 enterovirus-associated HFMD patients in 2018 were analysed in this study. Molecular diagnostic methods were performed to identify its serotypes. Phylogenetic analyses were depicted based on the complete VP1 gene. RESULTS: There were 21 enterovirus serotypes detected in Guangzhou in 2018. Three serotypes of enterovirus, CVA-6 (364/1220, 29.8%), CVA-10 (305/1220, 25.0%), and CVA-16 (397/1220, 32.5%), were identified as the causative pathogens and accounted for 87.3% among all 1220 HFMD patients. In different seasons, CVA-6 was the predominant pathogen of HFMD during autumn, and CVA-10 as well as CVA-16 were more prevalent in summer. Patients infected by CVA-6, CVA-10 or CVA-16 showed similar clinical features and laboratory characteristics, and the ratios of severe HFMD were 5.8, 5.9, and 1.5% in the three serotypes. Phylogenetic analyses of VP1 sequences showed that the CVA-6, CVA-10, and CVA-16 sequences belonged to the sub-genogroup E2, genogroup E, and genogroup B1, respectively. CONCLUSIONS: CVA-6, CVA-10, and CVA-16 were the predominant and co-circulated serotypes in Guangzhou China, 2018, which should be the new target for prevention and control of HFMD. Our findings provide useful information for diagnosis, treatment, and prevention of HFMD.

[Distribution of peripheral blood lymphocyte subsets in 826 healthy children aged 0-6 years].

OBJECTIVE: To study the distribution of peripheral blood lymphocyte subsets in healthy children aged 0-6 years. METHODS: A total of 826 healthy Han children aged 0-6 years were recruited. According to their age, the children were divided into four groups: newborn, infant, toddler and preschool. Their peripheral blood samples were collected to measure the percentages of lymphocyte subsets by flow cytometry. RESULTS: There were significant differences in the percentages of CD3+ T cells, CD3+CD4+ T cells and CD3-CD19+ B cells and the CD4+/CD8+ ratio between boys and girls (P<0.05). The girls had a lower percentage of CD3-CD19+ B cells, higher percentages of CD3+ T cells and CD3+CD4+ T cells and a higher CD4+/CD8+ ratio than the boys. The newborn group had the highest percentages of CD3+ T cells and CD3+CD4+ T cells and the highest CD4+/CD8+ ratio (P<0.05). The percentage of CD3+CD4+ T cells and the CD4+/CD8+ ratio gradually decreased with age and the preschool group had the lowest values (P<0.05). The newborn group had the lowest percentages of CD3-CD19+ B cells and CD3-CD16+CD56+ NK cells (P<0.05). The percentage of CD3-CD16+CD56+ NK cells gradually increased with age and the preschool group had the highest percentage (P<0.05). The percentage of CD3-CD19+ B cells reached the peak in the toddler period and then decreased with age (P<0.05). The preschool group had the highest percentage of CD3+CD8+ T cells (P<0.05). The variation trend of distribution of lymphocyte subsets in boys from different age groups was consistent with that in children from different age groups. For girls, the newborn group had the highest percentage of CD3+CD4+ T cells and CD4+/CD8+ ratio (P<0.05). CONCLUSIONS: The distribution of peripheral blood lymphocyte subsets in healthy children is significantly different across ages and sexes. Therefore, the reference values should be established according to age and sex.

Clinical and epidemiological features of the 2014 large-scale dengue outbreak in Guangzhou city, China.

BACKGROUND: Dengue virus is transmitted by mosquito around the tropical and sub-tropical regions. There was a large-scale dengue epidemic in Guangdong province, China during 2014 and around fifty thousands dengue fever cases, including six deaths, have been reported. In this study, we aimed to understand the clinical characteristics of hospitalized patients with laboratory-confirmed dengue virus (DENV) infection and determined the origin of the virus from the outbreak. METHODS: We have summarized the data from 138 hospitalized patients who were laboratory confirmed for dengue infection in Guangzhou city. Patients were classified as either non-severe dengue fever or severe dengue fever according to the guidelines from the WHO. Viral serotypes were determined by real time RT-PCR. Genetic sequences of the envelope and non-structural genes were amplified and analyzed from the serum samples of eleven patients. RESULTS: Co-circulation of dengue serotype 1 and 2 were identified from the outbreak. Patients infected by serotype 1 or 2 showed similar clinical features. Patients with severe dengue fever showed prolonged hospitalization and significant impairment of organ functions. Four samples from serotype 1 and five samples from serotype 2 were closely related respectively and clustered with Guangzhou isolates from previous years. The remaining isolates of serotype 1 were related to viruses found in Malaysia, India, Bangladesh and Singapore. CONCLUSION: The phylogenetic grouping of Guangdong isolates suggests that dengue is no longer an imported disease in China. Analysis of the isolates obtained in this study together with the size of the outbreak are suggestive of endemic circulation in Guangdong province.

[Resource situation investigation and analysis about endangered Chinese herbal medicine Daphnes Cortex].

In order to figure out the status and distribution of the wild and cultivated resources of traditional Chinese medicine Daphnes Cortex, its suitable habitat and endangering factors were analyzed to provide the basis for its rational use, protection and cultivation.Our research group tooka resources survey in Shanxi, Gansu, Sichuan and Qinghai provinces, which include 23 counties. Investigation and sampling investigation combined with interview were carried out. The total reserve of resources was estimated through route-quadrat method in combination with the vegetation and soil-type map area method. The results indicated that there was no obvious change between the present distribution ranges of the wild Daphnes Cortex and its historical records, but the density of the population has undergone major changes. The wild reserves resources has declined seriously, even on the verge of exhaustion in some regions. According to the survey results, the current total reserve of the wild Daphnes Cortex in the four provinces was no more than 600 tons. Simultaneously, we only found the cultivated resource in a mountain at an altitude of about 2 800 m in Kang county of Gansu province, which cropping scope was about 33 000 m². The cultivated resource can't provide medicinal products at present, because their growing period is too short to have curative effect. Destructive excavation and the longer growth cycle result in a sharp decline of the wild resources reserves, even to the point of extinction. Artificial cultivation of product will become the main source of medicinal resources in the future. Therefore, we must protect its suitable habitat, formulate rational harvesting policy, strengthen the supervision of government departments, collect and establish the germplasm nursery and seed bank. On the basis, we must carry out studies into seed-selecting and breeding as well as rapid propagation and growth technology at once.

Subchronic exposure to di-(2-ethylhexyl) phthalate (DEHP) elicits blood-brain barrier dysfunction and neuroinflammation in male C57BL/6J mice.

BACKGROUND: Exposure to di-(2-ethylhexyl) phthalate (DEHP) can cause neurotoxicity but the mechanism is not clear. Blood brain barrier (BBB) is one of the most important tissues to protect the brain. However, whether DEHP can disrupt the BBB or not remains unclear. The objective of this study is to investigate the potential effects of subchronic DEHP exposure on BBB integrity and discuss the role of BBB in DEHP inducible neurotoxicity with an emphasis on neuroinflammatory responses. Male adult C57BL/6J mice were orally administered with vehicle or 200 or 750 mg/kg/day DEHP for 90 days. Subchronic exposure to high-dose DEHP increased water intake but decreased body weight and brain weight. The concentrations of DEHP metabolites increased in serum from all DEHP-exposed groups while increased in brain only from the high-dose group. DEHP induced neurobehavioural alterations and damaged hippocampal neurons. DEHP increased BBB permeability by Evans blue (EB) extravasation and decreased tight junction proteins (ZO-1, occludin, and claudin-5) while presenting a neuroinflammatory feature characterized by the upregulated inflammatory mediators TNF-α and the NLRP3/caspase-1/IL-1ß inflammasome pathway. Our data provide new insights into neurotoxicity caused by subchronic DEHP exposure, which is probably involved in BBB dysfunction and neuroinflammatory responses.

[Comparison of the clinical value of three reciprocating single nickel-titanium instruments in preparation of simulated curved root canals].

PURPOSE: To explore the application value of three reciprocating single nickel-titanium instruments in preparation of simulated curved root canals. METHODS: One hundred and fifteen single-curved resin simulation root canals were selected and divided into Reciproc group (group A, 28), One file group (group B, 29), Wave One group (group C, 29) and control group (group D, 29) by random graph method. The simulated root canals were prepared according to the specifications of the instructions, root canal preparation, resin removal, root canal cleaning effect, center positioning ability and root canal width were compared. SPSS 22.0 software package was used for statistical analysis. RESULTS: There was no significant difference in quality and curvature among four groups(P＞0.05). The difference in root canal preparation time among the four groups was statistically significant (P＜0.05), and the root canal preparation time in group B was the shortest(P＜0.05). Comparison of resin removal at the root canal orifice and the midpoint of the bending start point among four groups, the difference was statistically significant(P＜0.05). The root canal wall debris scores and smear layer scores in four groups were significantly different(P＜0.05). Compared with group A, B and D, the root canal wall debris scores of the crown, middle and tip of group C were the lowest, the scores of smear layer on the crown and middle of the root canal wall was the lowest(P＜0.05). There was no significant difference in the center positioning ability of the four groups at 5 mm, 6 mm and 7 mm from the apical foramen(P＞0.05). There was no significant difference in root canal width among four groups (P＞0.05). CONCLUSIONS: Reciproc, One file and Wave One reciprocating single nickel-titanium instruments can maintain the original shape of the simulated root canal. Compared with Reciproc and Wave One, One file has better root canal shaping ability and cleaning effect.

Experimental investigation of the influence of the hydraulic performance of an axial blood pump on intraventricular blood flow.

Blood flow inside the left ventricle (LV) is a concern for blood pump use and contributes to ventricle suction and thromboembolic events. However, few studies have examined blood flow inside the LV after a blood pump was implanted. In this study, in vitro experiments were conducted to emulate the intraventricular blood flow, such as blood flow velocity, the distribution of streamlines, vorticity and the standard deviation of velocity inside the LV during axial blood pump support. A silicone LV reconstructed from computerized tomography (CT) data of a heart failure patient was incorporated into a mock circulatory loop (MCL) to simulate human systemic circulation. Then, the blood flow inside the ventricle was examined by particle image velocimetry (PIV) equipment. The results showed that the operating conditions of the axial blood pump influenced flow patterns within the LV and areas of potential blood stasis, and the intraventricular swirling flow was altered with blood pump support. The presence of vorticity in the LV from the thoracic aorta to the heart apex can provide thorough washing of the LV cavity. The gradually extending stasis region in the central LV with increasing blood pump support is necessary to reduce the thrombosis potential in the LV.

[Temporal expression of PD-1 and PD-L1 during the development of experimental periodontitis in rats and its implications].

PURPOSE: To study the temporal expression of programmed death receptor 1 (PD-1) and its ligand (PD-L1) in the development of periodontitis in rats. METHODS: SD rats were randomly divided into control group and model group, and 4 subgroups were divided in each model group according to the time of measurement: group A (1 week), group B (2 weeks), group C (3 weeks) and group D (4 weeks). There were 8 rats in each subgroup. Maxillary periodontitis models were made by using "thread ligation + vaccination LPS-PG" in rats. Periodontal tissue specimens were examined and bone resorption areas were determined in each group. Tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-1ß), interleukin 6 (IL-6) and transforming growth factor beta (TGF-ß) mRNA in periodontal tissue in each group were determined by RT-PCR method. PD-1 and PD-L1 protein expression in periodontal tissues in each group were determined by Western blotting. The data were analyzed by SPSS 22.0 software package. RESULTS: During modeling period, amelocemental junction-alveolar crest(ACJ-AC) distance and bone resorption area of the first molar in model group gradually increased (P<0.05), which were significantly different from the control group at the corresponding time point (P<0.01). During modeling period, TNF-α, IL-1ß and IL-6 mRNA level in periodontal tissues in the model group was continuously increased(P<0.05), and TGF-ß mRNA was continuously decreased(P<0.05), which was significantly different from the control group at the corresponding time point(P<0.01). During disease progress, PD-1 and PD-L1 protein level in periodontal tissues in each model group was continuously increased(P<0.05), which was significantly different from the control group at the corresponding time point (P<0.01); and PD-1 and PD-L1 protein levels in periodontal tissues in each model group was positively correlated to TNF-α and IL-6 mRNA levels(P<0.01). CONCLUSIONS: PD-1, as an immunosuppressive molecule and its receptor PD-L1, can promote the progression of periodontal inflammation, and its effect may be achieved by regulating the expression of TNF-α and IL-6.Regulating the expression of PD-1 and PD-L1 may be a new target for the treatment of periodontitis.

Cyclometalated Iridium(III) Complexes Containing 2-Phenylbenzo[d]oxazole Ligand: Synthesis, X-ray Crystal Structures, Properties and DFT Calculations.

Two new iridium(III) complexes were synthesized and fully characterized, [(bo)2Ir(pzpy)] (2a) and [(bo)2Ir(pzpyz)] (2b) (where bo = 2-phenylbenzo[d]oxazole, pzpy = 2-(1H-pyrazol-3-yl)pyridine, pzpyz = 2-(1H-pyrazol-3-yl)pyrazine). The single crystal structures of 2a-2b have been determined. Considering the relationship between their structures and photophysical properties, DFT calculations have been used to further support this inference. These Ir(III) complexes emit from the excited state of 3MLCT/3LLCT in the green and yellow region, and the quantum yields in the degassed CH2Cl2 solution at room temperature are 35.2% and 46.1%. Theoretical and experimental results show that iridium(III) complexes 2a-2b are promising phosphorescent material.

Automatic tube potential selection with tube current modulation in coronary CT angiography: Can it achieve consistent image quality among various individuals?

The present study included a total of 111 consecutive patients who had undergone coronary computed tomography (CT) angiography, using a first-generation dual-source CT with automatic tube potential selection and tube current modulation. Body weight (BW) and body mass index (BMI) were recorded prior to CT examinations. Image noise and attenuation of the proximal ascending aorta (AA) and descending aorta (DA) at the middle level of the left ventricle were measured. Correlations between BW, BMI and objective image quality were evaluated using linear regression. In addition, two subgroups based on BMI (BMI ≤25 and >25 kg/m2) were analyzed. Subjective image quality, image noise, the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR) were all compared between those. The image noise of the AA increased with the BW and BMI (BW: r=0.453, P<0.001; BMI: r=0.545, P<0.001). The CNR and SNR of the AA were inversely correlated with BW and BMI, respectively. The image noise of the DA and the CNR and SNR of the DA exhibited a similar association to those with the BW or BMI. The BMI >25 kg/m2 group had a significant increase in image noise (33.1±6.9 vs. 27.8±4.0 HU, P<0.05) and a significant reduction in CNR and SNR, when compared with those in the BMI ≤25 kg/m2 group (CNR: 18.9±4.3 vs. 16.1±3.7, P<0.05; SNR: 16.0±3.8 vs. 13.6±3.2, P<0.05). Patients with a BMI of ≤25 kg/m2 had more coronary artery segments scored as excellent, compared with patients with a BMI of >25 kg/m2 (P=0.02). In conclusion, this method is not able to achieve a consistent objective image quality across the entire patient population. The impact of BW and BMI on objective image quality was not completely eliminated. BMI-based adjustment of the tube potential may achieve a more consistent image quality compared to automatic tube potential selection, particularly in patients with a larger body habitus.

Orientation and property of fibers of the myodural bridge in humans.

BACKGROUND CONTEXT: Studies over the past 20 years have revealed that there are fibrous connective tissues between the suboccipital muscles, nuchal ligament, and cervical spinal dura mater (SDM). This fibrous connection with the SDM is through the posterior atlanto-occipital or atlantoaxial interspaces and is called the myodural bridge (MDB). Researchers have inferred that the MDB might have important functions. It was speculated that the function of MDB might be related to proprioception transmission, keeping the subarachnoid space and the cerebellomedullary cistern unobstructed, and affecting the dynamic circulation of the cerebrospinal fluid. In addition, clinicians have found that the pathologic change of the MDB might cause cervicogenic or chronic tension-type headache. Previous gross anatomical and histologic studies only confirmed the existence of the MDB but did not reveal the fiber properties of the MDB. This is important to further mechanical and functional research on the MDB. PURPOSE: Multiple histologic staining methods were used in the present study to reveal the various origin and fiber properties of the MDB. Muscles and ligaments participating in forming the MDB at the posterior atlanto-occipital or atlantoaxial interspaces were observed, and the fiber properties of the MDB were confirmed. The present study provides a basis for speculating the tensile force values of the MDB on the SDM and a morphologic foundational work for exploring the physiological functions and clinical significances of the MDB. STUDY DESIGN: Anatomical and histologic analyses of suboccipital structures that communicate with the SDM at the posterior atlanto-occipital or atlantoaxial interspaces were carried out. METHODS: Multiple histologic staining methods were used to evaluate the histologic properties and composition of the MDB at the posterior atlanto-occipital or atlantoaxial interspaces in five formalin-fixed head-neck human specimens. RESULTS: The results show that the MDB traversing the atlanto-occipital interspace originated from the rectus capitis posterior minor (RCPmi). The MDB traversing the atlantoaxial interspace originated mainly from the RCPmi, rectus capitis posterior major, and obliquus capitis inferior. These fibers form the vertebral dural ligament in the atlantoaxial interspace and connect with SDM. The MDB is mainly formed by parallel running type I collagen fibers; thus, suboccipital muscle could pull SDM strongly through the effective force propagated by the MDB during head movement. CONCLUSIONS: Myodural bridge is mainly formed by parallel running type I collagen fibers; thus, it can transmit the strong pull from the diverse suboccipital muscles or ligaments during head movement. The results of the present study will serve as a basis for further biomechanical and functional MDB research.

[Variations and Influencing Factors of Oral Bioaccessibility of Polybrominated Diphenyl Ethers in Soils Using an In-vitro Gastrointestinal Model].

Intake of contaminated soils is considered as an important exposure pathway of polybrominated diphenyl ethers (PBDEs) to humans, especially for children during their outdoor hand-to-mouth activities. Oral bioaccessibility is an essential tool to quantitatively assess the exposure risk of pollutants. In this study, we employed an in vitro digestion model to mimic the gastrointestinal digestion of typical PBDEs (BDE-28, BDE-47, BDE-99 and BDE-153 at a series of initial concentrations) in three natural soil samples with different TOC contents and to verify a previous hypothesis that the sorption of PBDE fraction mobilized from soil into digestive fluid on the surface of residual solid phase may lead to an underestimation of bioaccessibility of PBDEs. In addition, a method with multiple fluid-to-solid ratios was applied to calibrate the underestimation. The results indicated that the calibrated digestibility values were commonly higher than those without correction. For the different soil samples, the averaged increasing rates of PBDE digestibility at different initial concentrations ranged from 14.3% to 42.3%, from 11.1% to 32.1%, from 4.9% to 12.3% and from 0.0% to 7.7% for BDE-28, BDE-47, BDE-99 and BDE-153, respectively. Therefore, the bioaccessibility of PBDEs in gastrointestinal gut would be significantly underestimated without calibration, especially for tri- and tetra-BDEs and soil samples with low TOC contents or high PBDEs concentrations. The corrected digestibility values of BDE-28, BDE-47, BDE-99 and BDE-153 were 21.9%-54.7%, 18.8%-43.1%, 13.4%-27.2% and 9.3%-19.9%, respectively. The results indicated that the PBDEs digestibility was negatively correlated with lgK(ow); whereas there was no significant correlation of PBDE bioaccessibility with TOC contents in soils or with initial concentrations of PBDEs, particularly for the highly brominated components.

Ultrasound-targeted transfection of tissue-type plasminogen activator gene carried by albumin nanoparticles to dog myocardium to prevent thrombosis after heart mechanical valve replacement.

BACKGROUND: There are more than 300,000 prosthetic heart valve replacements each year worldwide. These patients are faced with a higher risk of thromboembolic events after heart valve surgery and long-term or even life-long anticoagulative and antiplatelet therapies are necessary. Some severe complications such as hemorrhaging or rebound thrombosis can occur when the therapy ceases. Tissue-type plasminogen activator (t-PA) is a thrombolytic agent. One of the best strategies is gene therapy, which offers a local high expression of t-PA over a prolonged time period to avoid both systemic hemorrhaging and local rebound thrombosis. There are some issues with t-PA that need to be addressed: currently, there is no up-to-date report on how the t-PA gene targets the heart in vivo and the gene vector for t-PA needs to be determined. AIMS: To fabricate an albumin nano-t-PA gene ultrasound-targeted agent and investigate its targeting effect on prevention of thrombosis after heart mechanic valve replacement under therapeutic ultrasound. METHODS: A dog model of mechanical tricuspid valve replacement was constructed. A highly expressive t-PA gene plasmid was constructed and packaged by nanoparticles prepared with bovine serum albumin. This nanopackaged t-PA gene plasmid was further cross-linked to ultrasonic microbubbles prepared with sucrose and bovine serum albumin to form the ultrasonic-targeted agent for t-PA gene transfection. The agent was given intravenously followed by a therapeutic ultrasound treatment (1 MHz, 1.5 w/cm(2), 10 minutes) of the heart soon after valve replacement had been performed. The expression of t-PA in myocardium was detected with multiclonal antibodies to t-PA by the indirect immunohistochemical method. Venous blood t-PA and D-dimer contents were tested before and 1, 2, 4, and 8 weeks after the operation. RESULTS: The high expression of t-PA could be seen in myocardium with increases in blood t-PA and D-dimer contents and thrombosis was prevented 8 weeks after operation. CONCLUSION: We successfully fabricated an albumin nano-t-PA gene ultrasound-targeted agent that could prevent dog thrombosis after mechanical heart valve replacement. Our study provides an experimental basis for prevention of human thrombosis-related diseases.