[Role of interleukin-6 in human umbilical vein endothelial cell to mesenchymal cell transformation]

Objective: To observe the effect of interleukin-6 (IL-6) on the phenotype and function of human umbilical vein endothelial cells (HUVECs) and explore the role of IL-6 in the process of endothelial-to-mesenchymal transition (EndMT). Methods: The experimental research method was used. Fresh umbilical cord discarded after normal maternal delivery was collected. On the second day of the primary cell isolation and cultivation, the cell morphology was observed under inverted phase contrast microscope. HUVECs of the 4th passage were identified by immunofluorescence method, and 2 batches of HUVECs ofthe 3rd to 5th passages were used for the subsequent experiments. The first batch of cells were divided into 6 groups according to the random number table (the same below): blank control group, 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group. The second batch of cells were divided into 4 groups: blank control group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group,and 50 ng/mL IL-6 group; the cells in blank control group was cultured with complete culture medium only, while the cells in the other groups were added with IL-6 of the corresponding final mass concentrations.Cells from the 1st batch were cultured for 72 hours after grouping, the morphology of HUVECS in the 6 groups was observed under inverted phase contrast microscope. At 72 h after grouping culture, the positive expressions of coagulation factor Ⅷ and α vascular smooth muscle actin (α-SMA) in HUVECs in the 6 groups were detected by immunofluorescence method, and the ratio of the number of double positive cells to the number of coagulation factor Ⅷ positive cells (the ratio of double positive cells for short) was calculated, with 6 samples per group; mRNA expression levels of vascular endothelial cadherin and α-SMA of HUVECs in 6 groups were detected by reverse transcription-polymerase chain reaction, with 3 samples per group.Cells from the 2nd batch were cultured 72 hours after grouping, the protein expression levels of vascular endothelial cadherin, α-SMA, and type Ⅰ collagen in the 4 groups were detected by Western blotting, with 3 samples per group. Data were statistically analyzed with one-way analysis of variance and Bonferroni correction. Results: On the 2nd day after isolation and cultivation, the primary cells were in short spindle shape or polygon, cells of the 4th passage were identified as HUVECs by immunofluorescence method. At 72 hours of culture after grouping, the cells from the 1st batch in the 6 groups changed to long spindle shape morphologically along with the increase of IL-6 concentration, the intercellular connections decreased or disappeared with the gap between cells becoming larger. At 72 h after grouping culture, compared with that inblank control group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 5 ng/mL IL-6 group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 10 ng/mL IL-6 group, the ratio of double positive cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly increased (P<0.01); the ratio of double positive cells in 100 ng/mL IL-6 group was significantly increased compared with those in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly decreased (P<0.01 or P<0.05); compared with that in 5 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 10 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 25 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of α-SMA of cells in 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6, group, and 100 ng/mL IL-6 group were significantly increased (P<0.05 or P<0.01). Cells from the 2nd batch were cultured for 72 hours after grouping. Compared with 1.391±0.026 in blank control group, the protein expressions of vascular endothelial cadherin of cells in 10 ng/mL IL-6 group (1.185±0.063), in 25 ng/mL IL-6 group (0.717±0.078), and in 50 ng/mL IL-6 group (0.239±0.064) were significantly decreased (P<0.05); compared with that in 10 ng/mL IL-6 group, the protein expressions of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 25 ng/mL IL-6 group, the protein expression of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group was significantly decreased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expression levels of α-SMA of cells in 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, and 50 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 10 ng/mL IL-6 group, the protein expression levels of α-SMA of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expressions of type Ⅰ collagen of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (P<0.05). Conclusions: After IL-6 treatment, the phenotype and function of HUVECS showed the characteristics of mesenchymal cells in a concentration-dependent manner. The inflammatory factor can promote the process of EndMT, and become one of the important factors regulating the mechanism of tissue fibrosis.

[The effect on patient life quality of prophylactic treatment to seasonal allergic rhinitis and related transcriptomics research]

Objective: The preseason prophylactic treatment of seasonal allergic rhinitis (AR) caused by pollens could alleviate AR symptoms during the pollen season. This study aimed to evaluate the effect of prophylaxis usage of suplatast tosilate on the life quality of AR patients in the pollen season, and investigate the potential mechanism of action through transcriptomic analysis. Methods: This is a randomized controlled study. AR patients allergic to weed pollens were recruited from Allergy Clinic of Peking Union Medical College Hospital from January 2020 to June 2020, and divided into prophylactic group who started to take suplatast tosilate as prophylaxis 2 weeks before the spread of weed pollens[n=10, 4 men and 6 women with age range of (34±6) years old] and control group who did not use any prophylactic treatment[n=24, 12 men and 12 women with age range of (33±9) years old]. The differences of age (t=0.381, P=0.706) and gender (χ²=0.595, P=0.715) distribution between the patients of two groups were not statistically significant. All the subjects filled in the rhinoconjunctivitis quality of life questionnaire (RQLQ) while onset of AR symptoms, and peripheral blood was drawn for transcriptomic analysis 1 month before and during the pollen season. Differences between groups were statistically analyzed through chi-square test and t test. Results: There was no significant difference in visual analogue scale of rhinitis symptom in the last pollen season between prophylactic group and control group[ 8.0 (6.4, 9.3) vs 7.3 (6.1, 8.0), Z=1.180, P=0.254]. The RQLQ score of prophylactic group was superior to that of control group in the weed pollen season (2.9±0.9 vs 3.7±0.9, t=-2.438, P=0.026). 210 differentially expressed genes of fold change ≥2 were identified, with 147 genes upregulated and 63 genes downregulated in the prophylactic group compared to the control group. Gene Ontology annotation showed that IL-12 and IL-23 related pathways were downregulated in prophylactic group (P=0.006 48). Polymerase Chain Reaction (PCR) verification of differentially expressed genes indicated that the relative expression level of HLA-G in prophylactic group was significantly lower than that in control group (0.23±0.19 vs 1.00±0.49,t=4.016, P=0.006). Conclusion: The prophylactic treatment of suplatast tosilate showed some benefit to the life quality of seasonal AR patients during the pollen season, and the potential mechanism might be related with the downregulation of IL-12 and IL-23 pathways and decreased expression of HLA-G.

[Appropriate protocol of treatment modulation for seasonal allergic rhinitis caused by cypress pollens]

Objective: To investigate appropriate protocol of treatment modulation for seasonal allergic rhinitis (AR) patients, in order to promote the implementation of personalized medicine. Methods: Total of 124 AR patients allergic to cypress pollens were recruited from January to February 2020 in Department of Allergy in Peking Union Medical College Hospital, 43 males and 81 females with an average age of (41±9) years. The patients were divided into two groups with block randomization method. In the first group, treatment was modulated every two days according to the average daily rhinoconjunctivitis symptom score of the last two days (short-term symptom-score group); while in the second group, therapy regimen was adjusted every week based on the Allergic Rhinitis Control Test (ARCT) score of the last week (long-term ARCT group). The treatment level was up-regulated when the cypress pollen count increased and stayed at a high level (step-up pharmacotherapy stage); and treatment was down-regulated while the pollen count decreased (step-down pharmacotherapy stage). Daily symptom scores, medicine scores, and ARCT scores of the two groups were recorded and compared. Results: During the whole cypress pollen season, the daily rhinoconjunctivitis symptom score of short-term symptom-score group was significantly lower than that in long-term ARCT group(2.4±1.0 vs 2.7±1.0, P<0.01), and the difference between the two groups was more pronounced in the step-up pharmacotherapy stage than that in the step-down pharmacotherapy stage, while there was no statistical difference between the daily medicine scores of the two groups (P>0.05). During the pollen rising period, the ARCT score of short-term symptom-score group was significantly better than that of long-term ARCT group (21(19, 22) vs 20 (17, 21), P=0.049); while in the pollen peak period and decreasing period, the ARCT scores of the two groups showed no statistical difference (P>0.05). The proportion of incompliance with doctor's advice was higher in long-term ARCT group compared to that in short-term symptom-score group (30.1% vs 6.7%, P<0.001). Conclusion: The protocol of treatment modulation for seasonal AR patients allergic to pollens should be developed flexibly according to the variation trend of pollen allergen exposure, so as to implement the idea of personalized medicine.

M-BLUE protocol for coronavirus disease-19 (COVID-19) patients: interobserver variability and correlation with disease severity

AIM

To retrospectively evaluate the interobserver variability of intensive care unit (ICU) practitioners and radiologists who used the M-BLUE (modified bedside lung ultrasound in emergency) protocol to assess coronavirus disease-19 (COVID-19) patients, and to determine the correlation between total M-BLUE protocol score and three different scoring systems reflecting disease severity.

MATERIALS AND METHODS

Institutional review board approval was obtained and informed consent was not required. Ninety-six lung ultrasonography (LUS) examinations were performed using the M-BLUE protocol in 79 consecutive COVID-19 patients. Two ICU practitioners and three radiologists reviewed video clips of the LUS of eight different regions in each lung retrospectively. Each observer, who was blind to the patient information, described each clip with M-BLUE terminology and assigned a corresponding score. Interobserver variability was assessed using intraclass correlation coefficient. Spearman's correlation coefficient analysis (R-value) was used to assess the correlation between the total score of the eight video clips and disease severity.

RESULTS

For different LUS signs, fair to good agreement was obtained (ICC = 0.601, 0.339, 0.334, and 0.557 for 0-3 points respectively). The overall interobserver variability was good for both the five different readers and consensus opinions (ICC = 0.618 and 0.607, respectively). There were good correlations between total LUS score and scores from three systems reflecting disease severity (R=0.394-0.660, p<0.01).

CONCLUSION

In conclusion, interobserver agreement for different signs and total scores in LUS is good and justifies its use in patients with COVID-19. The total scores of LUS are useful to indicate disease severity.

Iron deficiency plays essential roles in the trigger, treatment, and prognosis of autosomal dominant hypophosphatemic rickets

By analyzing iron status of 14 ADHR patients, we found that iron deficiency was an important trigger of ADHR. Correcting iron deficiency significantly improved patients' symptoms. Meanwhile, patients' serum phosphate showed positive correlations with iron metabolism parameters and hemoglobin-related parameters, suggesting the necessity of monitoring and correcting the iron status in ADHR.

INTRODUCTION

Autosomal dominant hypophosphatemic rickets (ADHR) is unique for its incomplete penetrance, variety of disease onsets, and waxing and waning phenotypes. Iron deficiency is a trigger of ADHR. This study aimed to clarify the role of iron deficiency in ADHR.

METHODS

Data of clinical manifestations and laboratory examinations were collected from patients among eight kindreds with ADHR. Multiple regression and Pearson's correlation tests were performed to test the relationships of serum phosphate levels and other laboratory variables during the patients' follow-ups.

RESULTS

Among 23 ADHR patients with fibroblast growth factor 23 (FGF23) mutations, 14 patients presented with obvious symptoms. Ten patients had iron deficiency at the onset of ADHR, coinciding with menarche, menorrhagia, pregnancy, and chronic gastrointestinal bleeding. Two patients who did not have their iron status tested presented with symptoms after abortion and pregnancy in one patient each, which suggested that they also had iron deficiency at onset. Patients were treated with ferrous succinate tablets, vitamin C, and neutral phosphate and calcitriol. With correction of the iron status, the patients' symptoms showed notable improvement, with increased serum phosphate levels. Two patients' FGF23 levels also declined to the normal range. There were strong correlations between serum phosphate and serum iron levels (r = 0.7689, p < 0.0001), serum ferritin levels (r = 0.5312, p = 0.002), iron saturation (r = 0.7907, p < 0.0001), and transferrin saturation (r = 0.7875, p < 0.001). We also examined the relationships between serum phosphate levels and hemoglobin-related indices, which were significant (hemoglobin: r = 0.71, p < 0.0001; MCV: r = 0.7589, p < 0.0001; MCH: r = 0.8218, p < 0.0001; and MCHC: r = 0.7751, p < 0.0001). Longitudinal data of six patients' follow-up also showed synchronous changes in serum phosphate with serum iron levels.

CONCLUSIONS

Iron deficiency plays an important role in triggering ADHR. Monitoring and correcting the iron status are helpful for diagnosing and treating ADHR. Iron metabolism parameters and hemoglobin-related parameters are positively correlated with serum phosphate levels in patients with ADHR and iron deficiency, and these might serve as good indicators of prognosis of ADHR.

Adoptive transfer of immunomodulatory M2 macrophages suppresses experimental autoimmune encephalomyelitis in C57BL/6 mice via blockading NF-κB pathway

Macrophages play important roles in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE), and M2 macrophage may have anti-inflammatory effects. In this study, we elucidated the roles of M1 and M2 macrophages in the pathogenesis of EAE and the effects of treatment with M2 macrophages that target certain proinflammatory cytokines and with immunomodulatory preparations that beneficially influence the disease course. We found macrophages increased at the onset of clinical signs in the EAE group, consistent with an increased proportion of M1 macrophages and low numbers of M2 macrophages. As the disease progressed and the symptoms worsened, M1 macrophages decreased and M2 macrophages gradually increased until the peak. In the recovery stage, M2 macrophages gradually decreased. Treatment with M2 macrophages inhibited the nuclear factor kappa B (NF-κB) pathway, alleviated the symptoms of EAE, reduced inflammatory cell infiltration and demyelination in the central nervous system and decreased the numbers of macrophages in the spleens. BAY-11-7082, an NF-κB blocking agent, could reduce the total number of macrophages both in vivo and in vitro, effectively prevented EAE development and significantly inhibited EAE symptoms in mice. Our study demonstrates that macrophages may play a crucial role in the pathogenesis of EAE, while M2 macrophages have anti-inflammatory effects. Transfer of M2 macrophages to EAE mice can block the NF-κB pathway successfully and relieve EAE symptoms. Application of NF-κB blockers is useful in the prevention and treatment of EAE.

Inhibitory effects of ultrasound irradiation on Staphylococcus epidermidis biofilm

PURPOSE

We aimed to investigate whether low-intensity continuous and pulsed wave ultrasound (US) irradiation can inhibit the formation of Staphylococcus epidermidis biofilms, for potential application in the treatment of catheter-related bloodstream infections (CRBSI).

METHODS

S. epidermidis biofilms that formed on the bottom surfaces of 6-well plates were irradiated on the bottom surface using the sound cell incubator system for different intervals of time.

RESULTS

US irradiation with continuous waves for 24 h notably inhibited biofilm formation (p < 0.01), but the same US irradiation for 12 h had no remarkable effect. Further, double US irradiation with pulsed waves for 20 min inhibited biofilm formation by 33.6%, nearly two-fold more than single US irradiation, which reduced it by 17.9%.

CONCLUSION

US irradiation of a lower intensity (I_SATA = 6-29 mW/cm²) than used in a previous study and lower than recommended by the Food and Drug Administration shows potential for preventing CRBSI caused by bacterial biofilms.

[Analysis on clinical characteristics, diagnosis and treatment of 13 cases of infant hairy polyp]

Objective: To explore and analyze the clinical characteristics, diagnosis and treatment of infant hairy polyp. Methods: A retrospective analysis was made on 13 cases of hairy polyp confirmed by pathology, who were admitted to the Children's Hospital of Hebei Province from January 2010 to September 2019, including 4 males and 9 females, with a male-female ratio of 1∶2.25. The age ranged from 3 hours to 1 year, and the median age was 1 month. Twelve of the 13 children were found to have difficulty breathing or feeding. All the children received coblation resection under general anesthesia. The root pedicle of the mass was found in the lateral nasopharyngeal wall in 8 cases, in the junction of palatine and palatopharyngeal arch of tonsil and the tongue and esophageal entrance in 1 case, respectively. Nasal septum was found in 2 cases, including 1 case located between two incisors. The wound at the root pedicle was ablated and the bleeding was stopped completely. Results: Postoperative follow-up lasted from 3 months to 2 years, and there was no recurrence in 12 cases. Fibrolaryngoscope showed a mass of the right eustachian tube and pharyngeal mouth in 1 case 2 years after the surgery, which was considered recurrence of hairy polyps and lost after that. Conclusion: Hairy polyps in infants is a rare clinical disease, and its main symptom is upper respiratory tract obstruction. Early diagnosis and radical surgery are the key to the treatment of the disease.

Association between length of residence and prevalence of MRSA colonization among residents in geriatric long-term care facilities

Background

A high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization has been reported among residents in geriatric long-term care facilities (LTCFs). Some studies indicate that MRSA might be imported from hospitals into LTCFs via resident transfer; however, other studies report that high MRSA prevalence might be caused by cross-transmission inside LTCFs. We aimed to assess which factors have a large impact on the high MRSA prevalence among residents of geriatric LTCFs.

Methods

We conducted a cohort study among 260 residents of four geriatric LTCFs in Japan. Dividing participants into two cohorts, we separately analyzed (1) the association between prevalence of MRSA carriage and length of LTCF residence (Cohort 1: n = 204), and (2) proportion of residents identified as MRSA negative who were initially tested at admission but subsequently identified as positive in secondary testing performed at ≥2 months after their initial test (Cohort 2: n = 79).

Results

Among 204 residents in Cohort 1, 20 (9.8%) were identified as positive for MRSA. Compared with residents identified as MRSA negative, a larger proportion of MRSA-positive residents had shorter periods of residence from the initial admission (median length of residence: 5.5 vs. 2.8 months), although this difference was not statistically significant (p = 0.084). Among 79 residents in Cohort 2, 60 (75.9%) were identified as MRSA negative at the initial testing. Of these 60 residents, only one (1.7%) had subsequent positive conversion in secondary MRSA testing. In contrast, among 19 residents identified as MRSA positive in the initial testing, 10 (52.6%) were negative in secondary testing.

Conclusions

The prevalence of MRSA was lower among residents with longer periods of LTCF residence than among those with shorter periods. Furthermore, few residents were found to become MRSA carrier after their initial admission. These findings highlight that MRSA in LTCFs might be associated with resident transfer rather than spread via cross-transmission inside LTCFs.

Impact of the radiation effect on the energy storage density and wake-up behaviors of antiferroelectric-like Al-doped HfO2 thin films

The effect of the γ-ray total dose radiation on the energy storage density (ESD) and the phase transition of antiferroelectric-like (AFE-like) Al-doped HfO2 (HfAlO) thin films was investigated. The ESD property and wake-up behavior of the phase transition during the field cycling of the AFE-like HfAlO thin films were quantified before and after the radiation. The efficiency of the AFE-like thin films for energy storage slightly decreases as the total dose increases from 200 krad (Si) to 5 Mrad (Si), which is attributed to the radiation-induced trapped defects at the interfaces of HfAlO/TiN. Both the J-E, C-V, and εr-f characteristics of the AFE-like HfAlO thin films were also measured before and after the radiation at the same electrodes. These results further confirm that the ferroelectricity of the thin films can be reduced due to the radiation oxide trapped defects. It is worth noting that an enhanced wake-up behavior of the AFE-like HfAlO thin films can be observed after the radiation, which indicates that the transition from the antiferroelectric phase to the ferroelectric phase could be accelerated by the increased radiation-induced defects.

Association of mprF mutations with cross-resistance to daptomycin and vancomycin in methicillin-resistant Staphylococcus aureus (MRSA)

We first reported a phenomenon of cross-resistance to vancomycin (VCM) and daptomycin (DAP) in methicillin-resistant Staphylococcus aureus (MRSA) in 2006, but mechanisms underlying the cross-resistance remain incompletely understood. Here, we present a follow-up study aimed to investigate genetic determinants associated with the cross-resistance. Using 12 sets of paired DAP susceptible (DAP^S) and DAP non-susceptible (DAP^R) MRSA isolates from 12 patients who had DAP therapy, we (i) assessed susceptibility to DAP and VCM, (ii) compared whole-genome sequences, (iii) identified mutations associated with cross-resistance to DAP and VCM, and (iv) investigated the impact of altered gene expression and metabolic pathway relevant to the cross-resistance. We found that all 12 DAP^R strains exhibiting cross-resistance to DAP and VCM carried mutations in mprF, while one DAP^R strain with reduced susceptibility to only DAP carried a lacF mutation. On the other hand, among the 32 vancomycin-intermediate S. aureus (VISA) strains isolated from patients treated with VCM, five out of the 18 strains showing cross-resistance to DAP and VCM carried a mprF mutation, while 14 strains resistant to only VCM had no mprF mutation. Moreover, substitution of mprF in a DAP^S strain with mutated mprF resulted in cross-resistance and vice versa. The elevated lysyl-phosphatidylglycerol (L-PG) production, increased positive bacterial surface charges and activated cell wall (CW) synthetic pathways were commonly found in both clinical isolates and laboratory-developed mutants that carry mprF mutations. We conclude that mprF mutation is responsible for the cross-resistance of MRSA to DAP and VCM, and treatment with DAP is more likely to select for mprF-mediated cross-resistance than is with VCM.

Cerebral Microbleeds Are Associated with Loss of White Matter Integrity

BACKGROUND AND PURPOSE

Previous studies have shown that diffusion tensor imaging suggests a diffuse loss of white matter integrity in people with white matter hyperintensities or lacunes. The purpose of this study was to investigate whether the presence of cerebral microbleeds and their distribution are related to the integrity of white matter microstructures.

MATERIALS AND METHODS

The study comprised 982 participants who underwent brain MR imaging to determine microbleed status. The cross-sectional relation between microbleeds and the microstructural integrity of the white matter was assessed by 2 statistical methods: a multilinear regression model based on the average DTI parameters of normal-appearing white matter and Tract-Based Spatial Statistics analysis, a tract-based voxelwise analysis. Fiber tractography was used to spatially describe the microstructural abnormalities along WM tracts containing a cerebral microbleed.

RESULTS

The presence of cerebral microbleeds was associated with lower mean fractional anisotropy and higher mean diffusivity, axial diffusivity, and radial diffusivity, and the association remained when cardiovascular risk factors and cerebral small-vessel disease markers were further adjusted. Tract-Based Spatial Statistics analysis indicated strictly lobar cerebral microbleeds associated with lower fractional anisotropy, higher mean diffusivity, and higher radial diffusivity in the internal capsule and corpus callosum after adjusting other cerebral small-vessel disease markers, while only a few voxels remained associated with deep cerebral microbleeds. Diffusion abnormalities gradients along WM tracts containing a cerebral microbleed were not found in fiber tractography analysis.

CONCLUSIONS

Cerebral microbleeds are associated with widely distributed changes in white matter, despite their focal appearance on SWI.

Early antiviral treatment contributes to alleviate the severity and improve the prognosis of patients with novel coronavirus disease (COVID-19)

BACKGROUND

At present, the severity of patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a focal point.

METHODS

To assess the factors associated with severity and prognosis of patients infected with SARS-CoV-2, we retrospectively investigated the clinical, imaging and laboratory characteristics of confirmed 280 cases of novel coronavirus disease (COVID-19) from 20 January to 20 February 2020.

RESULTS

The median age of patients in the mild group was 37.55 years, whilst that in the severe group was 63.04 years. The proportion of patients aged over 65 years in the severe group was significantly higher than that of the mild group (59.04% vs. 10.15%, P < 0.05). 85.54% of severe patients had diabetes or cardiovascular diseases, which was significantly higher than that of the mild group (51.81% vs. 7.11%, P = 0.025; 33.73% vs. 3.05%, P = 0.042). Patients in the mild group experienced earlier initiation of antiviral treatment (1.19 ± 0.45 vs. 2.65 ± 1.06 days in the severe group, P < 0.001). Our study showed that comorbidity, time from illness onset to antiviral treatment and age >=65 were three major risk factors for COVID-19 progression, whilst comorbidity and time from illness onset to antiviral treatment were two major risk factors for COVID-19 recovery.

CONCLUSIONS

The elderly and patients with underlying diseases are more likely to experience a severe progression of COVID-19. It is recommended that timely antiviral treatment should be initiated to slow the disease progression and improve the prognosis.

Development of CRISPR-Cas13a-based antimicrobials capable of sequence-specific killing of target bacteria

The emergence of antimicrobial-resistant bacteria is an increasingly serious threat to global health, necessitating the development of innovative antimicrobials. Here we report the development of a series of CRISPR-Cas13a-based antibacterial nucleocapsids, termed CapsidCas13a(s), capable of sequence-specific killing of carbapenem-resistant Escherichia coli and methicillin-resistant Staphylococcus aureus by recognizing corresponding antimicrobial resistance genes. CapsidCas13a constructs are generated by packaging programmed CRISPR-Cas13a into a bacteriophage capsid to target antimicrobial resistance genes. Contrary to Cas9-based antimicrobials that lack bacterial killing capacity when the target genes are located on a plasmid, the CapsidCas13a(s) exhibit strong bacterial killing activities upon recognizing target genes regardless of their location. Moreover, we also demonstrate that the CapsidCas13a(s) can be applied to detect bacterial genes through gene-specific depletion of bacteria without employing nucleic acid manipulation and optical visualization devices. Our data underscore the potential of CapsidCas13a(s) as both therapeutic agents against antimicrobial-resistant bacteria and nonchemical agents for detection of bacterial genes.

CRISPR technology is emerging as a potential antimicrobial against antimicrobial-resistant bacteria. Here the authors develop a bacteriophage delivered Cas13a system for killing target bacteria and detecting bacterial genes.

1159 Sleep Traits And Incident Delirium During A Decade Of Follow-up In 173,000 Participants

Introduction

Delirium is an acute decline in attention and cognition that is with associated long-term cognitive dysfunction in elderly patients. Accumulating evidence points to strong associations between sleep health and disorders of the brain. We tested whether baseline sleep duration, chronotype, daytime dozing, insomnia or sleep apnea predict incident delirium during hospitalization.

Methods

We studied participants from the UK Biobank who have been followed for up to 10 years until 2017. We included 173,221 participants (mean age 60±5; range 50-71 at baseline) who had at least one episode of hospitalization/surgery and were free from prior episodes of delirium. Delirium diagnosis, hospitalization and surgical events were derived using ICD-10 coding. Multivariate logistic regression models were performed to examine the associations of self-reported baseline sleep duration (&lt;6hrs/6-9h/&gt;9h), daytime dozing (often/rarely), insomnia (often/rarely) and presence of sleep apnea (ICD-10 and self-report) with incident delirium during follow-up. Models were adjusted for demographics, education, Townsend deprivation index, and major confounders (number of hospitalizations/surgical procedures, BMI, diabetes, major cardiovascular diseases and risk factors, major neurological diseases, major respiratory diseases, cancer, alcohol, depression/anxiety, sedatives/sleep aides, antipsychotics, steroids and opioids).

Results

In total, 1,023 (5.7 per 1,000 subjects) developed delirium. A prior diagnosis of sleep apnea (n=1,294) saw almost a two-fold increased odds (OR 1.96, 95% CI: 1.30-2.30 p=0.001) while those who often had daytime dozing were also at increased risk (OR 1.35, 95% CI: 1.02-1.80, p=0.025). Both these effects were independent of each other. No independent effects on incident delirium were observed from sleep duration, insomnia, or chronotype.

Conclusion

Certain sleep disturbances, in particular sleep apnea and daytime dozing, are independently associated with an increased risk for developing delirium. Further work is warranted to examine underlying mechanisms and to test whether optimizing sleep health can reduce the risk of developing delirium.

Support

This work was supported by NIH grants T32GM007592, RF1AG064312, and RF1AG059867.

0259 Shiftworkers are at Increased Risk of Developing Chronic Pain and Opioid Use Disorders: A Study of 116,000 UK Biobank Participants Over a Decade

Introduction

In the current epidemic of opioid-related deaths, and widespread use of opioids to treat chronic pain, there is a pressing need to understand the underlying risk factors that contribute to such devastating conditions. Shiftwork has been associated with adverse health outcomes. We tested whether shiftwork during middle age is linked to the development of chronic pain and opioid misuse.

Methods

We studied 116,474 participants in active employment between 2006–2010 (mean age 57±8; range 37–71) from the UK Biobank, who have been followed for up to 10 years until 2017. We included participants who were free from all forms of self-reported pain, and were not taking opioid medications at baseline. Chronic pain and opioid use disorder diagnoses were determined using hospitalization records and diagnostic coding from ICD-10. Multivariate logistic regression models were performed to examine the associations of shiftwork status (yes/no) and nightshift frequency (none/occasional/permanent) and with incident chronic pain and/or opioid use disorder during follow-up. Models were adjusted for demographics, education, Townsend deprivation index, major confounders (BMI, diabetes, bone fractures/injuries, operations, peripheral vascular disease, joint/inflammatory diseases, cancer, standing/manual labor at work) and covariates (smoking, alcohol, high cholesterol, depression/anxiety, and cardiovascular diseases).

Results

In total, 190 (1.6/1,000) developed chronic pain or opioid use disorders. Shiftworkers (n=17,673) saw a 1.5-fold increased risk (OR 1.56, 95% CI: 1.08–2.24, p=0.01) relative to day workers. Within shiftworkers, those who reported occasional nightshift work (n=3,966) were most vulnerable (OR 1.57, 95% CI: 1.06–2.34, p=0.02). Results remained similar after adjusting for baseline sleep duration, chronotype and insomnia.

Conclusion

Shiftwork, and in particular rotating nightshift work is associated with increased risk for developing chronic pain and opioid use disorders. Replication is required to confirm the findings and to examine underlying mechanisms.

Support

This work was supported by NIH grants T32GM007592, RF1AG064312, and RF1AG059867.

Multiple-centre clinical evaluation of an ultrafast single-tube assay for SARS-CoV-2 RNA

OBJECTIVE

To evaluate the performance of an ultrafast single-tube nucleic acid isothermal amplification detection assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA using clinical samples from multiple centres.

METHODS

A reverse transcription recombinase-aided amplification (RT-RAA) assay for SARS-CoV-2 was conducted within 15 minutes at 39°C with portable instruments after addition of extracted RNA. The clinical performance of RT-RAA assay was evaluated using 947 clinical samples from five institutions in four regions of China; approved commercial fluorescence quantitative real-time PCR (qRT-PCR) kits were used for parallel detection. The sensitivity and specificity of RT-RAA were compared and analysed.

RESULTS

The RT-RAA test results of 926 samples were consistent with those of qRT-PCR (330 were positive, 596 negative); 21 results were inconsistent. The sensitivity and specificity of RT-RAA was 97.63% (330/338, 95% confidence interval (CI) 95.21 to 98.90) and 97.87% (596/609, 95% CI 96.28 to 98.81) respectively. The positive and negative predictive values were 96.21% (330/343, 95% CI 93.45 to 97.88) and 98.68% (596/604, 95% CI 97.30 to 99.38) respectively. The total coincidence rate was 97.78% (926/947, 95% CI 96.80 to 98.70), and the kappa was 0.952 (p < 0.05).

CONCLUSIONS

With comparable sensitivity and specificity to the commercial qRT-PCR kits, RT-RAA assay for SARS-CoV-2 exhibited the distinctive advantages of simplicity and rapidity in terms of operation and turnaround time.

[The comparison of step-down pharmacotherapy and maintaining dose therapy for seasonal allergic rhinitis]

Objective:There is no standard algorithm for the modulation of pharmacologic treatment of allergic rhinitis. This study aimed to recruited allergic rhinitis patients caused by cypress pollens, and compare the step-down pharmacotherapy guided by pollen count and the maintaining therapy which keeps the previous medicine dose when the pollen count decreased. Method:This was a randomized, open-labelled, parallel control study. During the period after the pollen peak when the cypress pollen count decreased and stayed at a low level, allergic rhinitis patients were randomly divided into two groups. In the step-down group（n=67） medicine dose was reduced, while the maintaining group（n=68） kept taking the same dose as in the peak season. The rhinitis symptom score and medicine score of these two groups were recorded and compared. Result:The daily rhinitis symptom score of the step-down group showed no significant difference with the symptom score of the maintaining group, 2.45±0.32 vs 2.43±0.41, P=0.788. But the medicine score of step-down group（3.67±0.98） was significantly lower than that of maintaining group（4.78±0.70）, P<0.001. The compliance of step-down group（80.6%） was also better than maintaining group（60.3%）, P=0.014. However, in the subgroup of patients with severe rhinitis symptoms, the symptoms of patients taking step-down therapy tended to be more severe than those maintaining the same dose. Conclusion:During the later period of the pollen season when the pollen count was relatively low, the step-down pharmacotherapy guided by pollen count could reduce the medication use, increase the compliance of patients while controlling their rhinitis symptoms effectively. But this strategy might be more suitable for patients with milder symptoms, the severe rhinitis sufferers should be cautious before reducing their medicine dose.

Corrigendum: Composition and Diversity of CRISPR-Cas13a Systems in the Genus Leptotrichia

[This corrects the article DOI: 10.3389/fmicb.2019.02838.].

Predicting the intervention threshold for initiating osteoporosis treatment among postmenopausal women in China: a cost-effectiveness analysis based on real-world data

This study built a micro-simulation Markov model to determine the treatment threshold of osteoporosis in postmenopausal women in Mainland China. Treatment with zoledronate is cost-effective when FRAX-based (Fracture risk assessment tool) fracture probability is over 7%.

INTRODUCTION

The purpose of this study is to estimate FRAX-based fracture probabilities in Mainland China using real-world data, at which intervention could be cost-effective.

METHODS

We developed a micro-simulation Markov model to capture osteoporosis states and relevant morbidities including hip fracture, vertebral fracture, and wrist fracture. Baseline characteristics including incidences of osteoporosis and distribution of risk factors were derived from the Peking Vertebral Fracture study, the largest prospective cohort study of postmenopausal women in Mainland China. We projected incidences of fractures and deaths by age groups under two treatment scenarios: 1) no treatment, and 2) zoledronate. We also projected total quality-adjusted life-years (QALY) and total costs including fracture management and osteoporosis drugs for cost-effectiveness analysis. Cost-effective intervention thresholds were calculated based on the Chinese FRAX model.

RESULTS

Treatment with zoledronate was cost-effective when the 10-year probability of major osteoporotic fracture based on FRAX was above 7%. The FRAX threshold increased by age from 51 to 65 years old, and decreased in elder age groups, ranging from 4% to 9%.

CONCLUSIONS

Using real-world data, our model indicated that widespread use of zoledronate was of both clinical and economic benefit among Chinese postmenopausal women. Using a FRAX-based intervention threshold of 7% with zoledronate should permit cost-effective access to therapy to patients and contribute to reducing the disease burden of osteoporosis in Mainland China.

[Analysis of related factors of secondary pulmonary infection in children with tracheobronchial foreign body]

Objective:To analyze the secondary pulmonary infection and the distribution of pathogenic bacteria in children with tracheobronchial foreign body, and to guide the clinical treatment. Method:The clinical data of 197 children with tracheobronchial foreign bodies confirmed by rigid bronchoscopy were reviewed. According to the clinical manifestations and signs, blood routine, chest CT and airway endocrine pathogen distribution, the secondary pulmonary infection was analyzed. Result:Seventy-five of 197 children with foreign bodies in tracheobronchial had secondary pulmonary infections. Among them, 32 cases of airway endocrine cultured pathogenic bacteria, mainly including Streptococcus pneumoniae and Haemophilus influenzae. Children with long preoperative history, fever, and with a history of using antibiotics are more likely to have secondary pulmonary infections. Conclusion:The duration of disease history, preoperative fever and the use of antibiotics are related to secondary pulmonary infection. The third generation of cephalosporins can effectively control the infection.

[Prevalence and influencing factors of carotid plaque in population at high-risk for cardiovascular disease in Jiangsu province]

Objective: To understand the prevalence of carotid plaque (CP) in population at high-risk for cardiovascular disease (CVD) in Jiangsu province and identify related influencing factors. Methods: Based on the China Patient-centered Evaluative Assessment of Cardiac Events Million Persons Project from 2015 to 2016, a total of 11 392 persons at high-risk for CVD were selected from six project areas in Jiangsu province for the questionnaire survey, physical measurement, laboratory test and bilateral ultrasound examination of carotid arteries. The prevalence of CP and influencing factors of abnormal carotid arteries, CP and plaque burden (CP≥2) were analyzed. Results: Among the persons surveyed, 4 821 (42.3%) were males. The age of the persons surveyed was (59.4±8.9) years. There were 5 971 abnormal carotid arteries cases (52.4%), including 1 782 carotid intima-media thickness thickening cases (15.6%), 3 811 CP cases (33.5%) and 378 carotid stenosis cases (3.3%). Older age (OR=2.253, 95%CI: 2.127-2.386), urban residence (OR=2.622, 95%CI: 2.375-2.895), hypertension (OR=1.439, 95%CI: 1.195-1.732), smoking (OR=1.441, 95%CI: 1.259- 1.650), pulse pressure difference (OR=1.270, 95%CI: 1.198-1.347), fasting plasma glucose (FPG) (OR=1.109, 95%CI: 1.059-1.161) and LDL-C/HDL-C (OR=1.225, 95%CI: 1.164-1.288) were possible risk factors of CP in population at high risk for CVD. Being women (OR=0.558, 95%CI: 0.494-0.630), high BMI (OR=0.948, 95%CI: 0.904-0.994), higher levels of education (OR=0.708, 95%CI: 0.531-0.945), and higher annual household income (OR=0.773, 95%CI: 0.669-0.894) were the possible protective factors. Conclusions: Over half of the population at high-risk for CVD in Jiangsu showed abnormal carotid arteries. High blood pressure, high blood glucose, high blood lipids and smoking were the main factors that could be changed.

Composition and Diversity of CRISPR-Cas13a Systems in the Genus Leptotrichia

Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas13a, previously known as CRISPR-C2c2, is the most recently identified RNA-guided RNA-targeting CRISPR-Cas system that has the unique characteristics of both targeted and collateral single-stranded RNA (ssRNA) cleavage activities. This system was first identified in Leptotrichia shahii. Here, the complete whole genome sequences of 11 Leptotrichia strains were determined and compared with 18 publicly available Leptotrichia genomes in regard to the composition, occurrence and diversity of the CRISPR-Cas13a, and other CRISPR-Cas systems. Various types of CRISPR-Cas systems were found to be unevenly distributed among the Leptotrichia genomes, including types I-B (10/29, 34.4%), II-C (1/29, 2.6%), III-A (6/29, 15.4%), III-D (6/29, 15.4%), III-like (3/29, 7.7%), and VI-A (11/29, 37.9%), while 8 strains (20.5%) had no CRISPR-Cas system at all. The Cas13a effectors were found to be highly divergent with amino acid sequence similarities ranging from 61% to 90% to that of L. shahii, but their collateral ssRNA cleavage activities leading to impediment of bacterial growth were conserved. CRISPR-Cas spacers represent a sequential achievement of former intruder encounters, and the retained spacers reflect the evolutionary phylogeny or relatedness of strains. Analysis of spacer contents and numbers among Leptotrichia species showed considerable diversity with only 4.4% of spacers (40/889) were shared by two strains. The organization and distribution of CRISPR-Cas systems (type I-VI) encoded by all registered Leptotrichia species revealed that effector or spacer sequences of the CRISPR-Cas systems were very divergent, and the prevalence of types I, III, and VI was almost equal. There was only one strain carrying type II, while none carried type IV or V. These results provide new insights into the characteristics and divergences of CRISPR-Cas systems among Leptotrichia species.

Probiotics Prevents Sensitization to Oral Antigen and Subsequent Increases in Intestinal Tight Junction Permeability in Juvenile-Young Adult Rats

Increased intestinal permeability is thought to underlie the pathogenesis of food allergy. We explore the mechanism responsible for changes in the morphology and function of the intestinal barrier using a rat model of food allergy, focusing on the contribution of intestinal microbiota. Juvenile–young adult rats were sensitized with ovalbumin and treated with antibiotics or probiotics (Clostridium butyricum and Lactobacillus reuteri), respectively. The serum ovalbumin-IgE levels, intestinal permeability, histopathological features, tight junction (TJ)-associated proteins, Th2 cytokines, and gut microbiota in feces were analyzed in each group. Sensitized rats showed an increase in ovalbumin-IgE levels and intestinal permeability with gut mucosal inflammation, whereas rats that received probiotics were only mildly affected. Rats given ovalbumin, but not those given probiotics, showed a reduction in both TJ-related protein expression and localization. Th2 cytokine levels were increased in the sensitized rats, but not in those given probiotics. TJs in rats treated with ovalbumin and antibiotics were disrupted, but those in rats administered probiotics were undamaged. Clostridiaceae were increased in the probiotics groups, especially Alkaliphilus, relative to the ovalbumin-sensitized group. Gut microbiota appears to play a role in regulating epithelial barrier function, and probiotics may help to prevent food sensitization through the up-regulation of TJ proteins.

Post-surgical meningitis caused by Klebsiella variicola

Klebsiella variicola, a member of K. pneumoniae phylogroup, can cause severe infectious diseases. We report a case of K. variicola meningitis after neurosurgery. The bacterium was isolated from blood and cerebrospinal fluid, and bacterial species identification was carried out by using both matrix-assisted laser-desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS) and whole genome sequencing. Initially, the organism was misidentified as K. pneumoniae by VITEK®2; automated system in the clinical laboratory examination. The patient recovered with the combination of surgical drainage and antimicrobial treatment. To our knowledge, this is the first case report of post-surgical meningitis caused by K. variicola. As experienced in this case, the automated bacterial identification system popularly being used in the clinical laboratory might not be effective enough for bacterial species identification. The use of MALDI-TOF MS for microbial identification may be helpful to physicians for appropriate management of K. pneumoniae phylogroup infection.

[Prevalence, awareness, treatment and control of hypertension in adult residents in Jiangsu province]

Objective: To investigate the prevalence, awareness, treatment and control of hypertension in adult residents in Jiangsu province and provide evidence for the prevention and control of hypertension. Methods: A population-based cardiovascular disease screening project was conducted during 2015-2018 in Jiangsu, a total of 95 348 community-dwelling adults aged 35-75 years from 6 project areas were included in the study. The prevalence rate of hypertension and rates of awareness, treatment and control of hypertension in the adults with different characteristics were analyzed. Multilevel model was applied to identify the influencing factors. Results: Among 95 348 adults surveyed, 54 407 were hypertensive, the standardized prevalence rate was 48.1%. The prevalence rate was significantly higher in males than in females (62.1% vs. 54.0%, P<0.05). Among the hypertension patients, the rates of awareness, treatment and control of hypertension were 56.6%, 45.3% and 12.0% (standardized rates: 52.2%, 41.0% and 11.2%), respectively, and all the rates were positively associated with age (all P<0.05). Multilevel model analysis showed that those who were males, at older age, lived in rural area, suffered from diabetes, had frequent alcohol drinking and those who were overweight/obese had higher risk for hypertension (all P<0.05). Among people with hypertension, those who had younger age, lower education level, lower household income level and those who had frequent alcohol drinking had lower awareness, treatment and control rates of hypertension (all P<0.05). Conclusions: The prevalence rate of hypertension was high, but related awareness, treatment and control rates were low in adult residents in Jiangsu province. Comprehensive measures should be taken to improve awareness, treatment and control of hypertension in whole population, especially in young adults, and those with low education or income levels.

Oxidative stress resistance and fitness-compensatory response in vancomycin-intermediate Staphylococcus aureus (VISA)

In this study, vancomycin-intermediate Staphylococcus aureus (VISA) cells carrying vraS and (or) graR mutations were shown to be more resistant to oxidative stress. Caenorhabditis elegans infected with these strains in turn demonstrated lower survival. Altered regulation in oxidative stress response and virulence appear to be physiological adaptations associated with the VISA phenotype in the Mu50 lineage.

Comparison of pharmacokinetics of tilmicosin in healthy pigs and pigs experimentally infected with Actinobacillus pleuropneumoniae

Aim: To compare the pharmacokinetic profiles of tilmicosin, administered orally at a single dose of 20 mg/kg bodyweight, in healthy pigs and in pigs experimentally infected with Actinobacillus pleuropneumoniae. Methods: Twelve healthy crossbred pigs, aged approximately 8 weeks, were randomly assigned to uninfected and infected groups, with six pigs per group. Pigs in the infected group were inoculated intranasally with a bacterial suspension of A. pleuropneumoniae containing approximately 10⁸ cfu. Each pig received a single oral dose of 20 mg/kg bodyweight of tilmicosin, given 3-4 hours after inoculation in infected pigs. Blood samples were collected before drug administration and up to 48 hours after tilmicosin administration. Concentrations of tilmicosin in plasma samples were determined by HPLC. Throughout the experimental period pigs were observed for signs of inappetence and clinical abnormalities. After sampling was complete pigs were subject to euthanasia and samples collected for gross and histopathology as well as microbiology. Results: Infected pigs showed signs of bradykinesia, nasal discharge dyspnoea, and coughing 1 hours after inoculation and A. pleuropneumoniae was cultured from the lungs of all infected pigs postmortem. Comparing pharmacokinetic parameters in uninfected and infected pigs, the maximum plasma concentration of tilmicosin was higher in uninfected pigs (1.17 (SD 0.17) vs. 0.96 (SD 0.17) µg/mL), the time to reach maximum concentration was shorter (1.53 (SD 0.23) vs. 2.40 (SD 0.37) hours), and the half-life of the absorption phase and half-life of the elimination phase were both shorter (0.66 (SD 0.08) vs. 1.00 (SD 0.27) hours) and (12.93 (SD 0.96) vs. 16.53 (SD 0.55) hours), respectively. The apparent volume of distribution was smaller in uninfected than infected pigs (1.91 (SD 0.22) vs. 2.16 (SD 0.21) L/kg). The relative bioavailability of tilmicosin in infected relative to uninfected pigs was 108.6 (SD 9.71)%. Conclusions and clinical relevance: The results of this study indicate that A. pleuropneumoniae infection significantly changed certain pharmacokinetic parameters of tilmicosin in pigs. In infected pigs tilmicosin exhibited a longer drug persistence and a better extent of absorption. These results indicate that it is necessary to monitor and adjust the dose of tilmicosin administration during the presence of pleuropneumonia. It is expected that this can optimise clinical efficacy and help avoid the development of resistance.

Analysis host-recognition mechanism of staphylococcal kayvirus ɸSA039 reveals a novel strategy that protects Staphylococcus aureus against infection by Staphylococcus pseudintermedius Siphoviridae phages

Following the emergence of antibiotic-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus pseudintermedius (MRSP), phage therapy has attracted significant attention as an alternative to antibiotic treatment. Bacteriophages belonging to kayvirus (previously known as Twort-like phages) have broad host range and are strictly lytic in Staphylococcus spp. Previous work revealed that kayvirus ɸSA039 has a host-recognition mechanism distinct from those of other known kayviruses: most of kayviruses use the backbone of wall teichoic acid (WTA) as their receptor; by contrast, ɸSA039 uses the β-N-acetylglucosamine (β-GlcNAc) residue in WTA. In this study, we found that ɸSA039 could switch its receptor to be able to infect S. aureus lacking the β-GlcNAc residue by acquiring a spontaneous mutation in open reading frame (ORF) 100 and ORF102. Moreover, ɸSA039 could infect S. pseudintermedius, which has a different WTA structure than S. aureus. By comparison, with newly isolated S. pseudintermedius-specific phage (SP phages), we determined that glycosylation in WTA of S. pseudintermedius is essential for adsorption of SP phages, but not ɸSA039. Finally, we describe a novel strategy of S. aureus which protects the bacteria from infection of SP phages. Notably, glycosylation of ribitol phosphate (RboP) WTA by TarM or/and TarS prevents infection of S. aureus by SP phages. These findings could help to establish a new strategy for the treatment of S. aureus and S. pseudintermedius infection, as well as provide valuable insights into the biology of phage-host interactions.

[In vitro study of the effect of human antigen R on lysosomal acidification during autophagy in mouse cardiomyocytes]

Objective: To investigate the effect of human antigen R on lysosomal acidification during autophagy in mouse cardiomyocytes cultured in vitro. Methods: The hearts of 20 C57BL/6 mice aged 1-2 days no matter male or female were isolated to culture primary cardiomyocytes which were used in the following experiments. (1) The cells were divided into 5 groups according to the random number table (the same grouping method below), i. e., normal control group and sugar-free serum-free 0.5, 1.0, 3.0, and 6.0 h groups. The cells in normal control group were routinely cultured for 54.0 h with Dulbecco's modified Eagle medium/nutrient mixture F12 (DMEM/F12) medium (the same regular culture condition below), and the cells in sugar-free serum-free 0.5, 1.0, 3.0, and 6.0 h groups were firstly regularly cultured for 53.5, 53.0, 51.0, 48.0 h and then cultured with replaced sugar-free serum-free medium for 0.5, 1.0, 3.0, and 6.0 h, respectively. The protein expressions of microtubule-associated protein 1 light chain 3 Ⅱ (LC3Ⅱ), autophagy-related protein 5, and adenosine triphosphatase V1 region E1 subunit (ATP6V1E1) were detected by Western blotting. (2) The cells were divided into normal control group and sugar-free serum-free 3.0 h group. The cells in corresponding groups were treated the same as those in experiment (1), and the cell lysosomal acidification level was observed and detected under a laser scanning confocal microscope. (3) Two batches of cells were grouped and treated the same as those in experiment (1). The protein expression of human antigen R in the whole protein of cells of one batch and its protein expression in the cytoplasm and nucleus protein of cells of the other batch were detected by Western blotting. (4) The cells were divided into normal control group, simple control small interfering RNA (siRNA) group, simple human antigen R-siRNA1 (HuR-siRNA1) group, simple HuR-siRNA2 group, sugar-free serum-free 3.0 h group, sugar-free serum-free+ control siRNA group, sugar-free serum-free+ HuR-siRNA1 group, and sugar-free serum-free+ HuR-siRNA2 group. After 48 hours of regular culture, the cells in simple control siRNA group and sugar-free serum-free+ control siRNA group were transfected with negative control siRNA for 6 h, the cells in simple HuR-siRNA1 group and sugar-free serum-free+ HuR-siRNA1 group were transfected with HuR-siRNA1 for 6 h, and the cells in simple HuR-siRNA2 group and sugar-free serum-free+ HuR-siRNA2 group were transfected with HuR-siRNA2 for 6 h. Hereafter, the cells in these 8 groups were continuously cultured for 48 h with regular conditon, and then the cells in normal control group and each simple siRNA-treated group were replaced with DMEM/F12 medium, the cells in the other groups were replaced with sugar-free serum-free medium, and they were cultured for 3 h. The protein expression of human antigen R in the whole protein of cells was detected by Western blotting. (5) Two batches of cells were divided into sugar-free serum-free+ control siRNA group and sugar-free serum-free+ HuR-siRNA1 group, and the cells in corresponding groups were treated the same as those in experiment (4). The distribution and expression of human antigen R in the cells of one batch were observed and detected by immunofluorescence method, and the lysosomal acidification level in the cells of the other batch was observed and detected under a laser scanning confocal microscope. (6) Three batches of cells were divided into sugar-free serum-free 3.0 h group, sugar-free serum-free+ control siRNA group, sugar-free serum-free+ HuR-siRNA1 group, and sugar-free serum-free+ HuR-siRNA2 group, and the cells in corresponding groups were treated the same as those in experiment (4). The protein expressions of cathepsin D in the whole protein of cells of one batch, human antigen R in the cytoplasm protein of cells of one batch, and ATP6V1E1 in the whole protein of cells of the other batch were detected by Western blotting. (7) The cells were divided into normal control group, sugar-free serum-free 3.0 h group, sugar-free serum-free+ control siRNA group, and sugar-free serum-free+ HuR-siRNA1 group, and the cells in corresponding groups were treated the same as those in experiment (4). The mRNA expression of ATP6V1E1 in cells was detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction. The sample number of each experiment was 3. Data were processed with independent data t test, one-way analysis of variance, least significant difference t test, and Bonferroni correction. Results: (1) Compared with those of normal control group, the protein expressions of LC3Ⅱ and ATP6V1E1 in the whole protein of cells of sugar-free serum-free 1.0, 3.0, and 6.0 h groups were significantly increased (t=12.16, 4.05, 4.82, 11.64, 3.29, 8.37, P<0.05 or P<0.01). Compared with that of normal control group, the protein expression of autophagy-related protein 5 in the whole protein of cells of sugar-free serum-free 0.5, 1.0, 3.0, and 6.0 h groups was significantly increased (t=6.88, 10.56, 5.76, 9.91, P<0.05 or P<0.01). (2) Compared with 1.03±0.08 of normal control group, the lysosomal acidification level in the cells of sugar-free serum-free 3.0 group (2.92±0.30) was significantly increased (t=6.01, P<0.01). (3) There was no statistically significant difference in the overall comparison of protein expression of human antigen R in the whole protein of cells among the 5 groups (F=1.09, P>0.05). Compared with that of normal control group, the protein expression of human antigen R in the cytoplasm protein of cells was significantly increased in sugar-free serum-free 1.0, 3.0, and 6.0 h groups (t=43.05, 11.07, 5.39, P<0.05 or P<0.01), while the protein expression of human antigen R in the nucleus protein of cells was significantly decreased in sugar-free serum-free 3.0 and 6.0 h groups (t=11.18, 12.71, P<0.01). (4) Compared with that of simple control siRNA group, the protein expression of human antigen R in the whole protein of cells of simple HuR-siRNA1 group and simple HuR-siRNA2 group was significantly decreased (t=4.82, 4.44, P<0.05). Compared with that of sugar-free serum-free+ control siRNA group, the protein expression of human antigen R in the whole protein of cells of sugar-free serum-free+ HuR-siRNA1 group and sugar-free serum-free+ HuR-siRNA2 group was significantly decreased (t=4.39, 6.27, P<0.05). (5) Compared with those of sugar-free serum-free+ control siRNA group, the distribution of human antigen R in the cytoplasm of cells and its expression level were significantly decreased in sugar-free serum-free+ HuR-siRNA1 group (t=10.13, P<0.01). Compared with 1.00±0.06 of sugar-free serum-free+ control siRNA group, the lysosomal acidification level (0.73±0.06) in the cells of sugar-free serum-free+ HuR-siRNA1 group was significantly decreased (t=3.28, P<0.01). (6) Compared with those of sugar-free serum-free+ control siRNA group, the protein expressions of cathepsin D in the whole protein of cells, human antigen R in the cytoplasm protein of cells, and ATP6V1E1 in the whole protein of cells were significantly decreased in sugar-free serum-free+ HuR-siRNA1 group and sugar-free serum-free+ HuR-siRNA2 group (t=4.16, 3.99, 4.81, 5.07, 11.68, 12.97, P<0.05 or P<0.01). (7) Compared with that of normal control group, the mRNA expression of ATP6V1E1 in the cells of sugar-free serum-free 3.0 h group was significantly increased (t=5.51, P<0.05). Compared with that of sugar-free serum-free+ control siRNA group, the mRNA expression of ATP6V1E1 in the cells of sugar-free serum-free+ HuR-siRNA1 group was significantly decreased (t=5.97, P<0.05). Conclusions: After sugar-free serum-free treatment in vitro, the autophagy in mouse primary cardiomyocytes is activated, the lysosomal acidification is enhanced, and the expression of human antigen R in cytoplasm is increased. Human antigen R function is activated and involved in maintaining lysosomal acidification during autophagy in mouse cardiomyocytes.

[Analysis of sensitization spectrum and clinical features of children with adenoid hypertrophy and perennial rhinitis]

Objective:To investigate the sensitization spectrum and clinical features of children with adenoid hypertrophy and perennial rhinitis.Method:A total of 121 children with adenoidal hypertrophy and perennial rhinitis were enrolled in the ENT Department of the Children's Hospital of the Capital Institute of Pediatrics and the Allergy Department of Peking Union Medical College Hospital from July to October in 2017. Nasopharyngoscopy was performed, and specific IgE were measured by blood sampling, and the sensitization spectrum and clinical characteristics of the children were analyzed. Result: Adenoid hypertrophy combined with allergic rhinitis accounted for 64.5% of the total, mold sensitization was the most common, accounting for 78.2% of allergic rhinitis patients, including boys accounted for 67.2%, gender differences were statistically significant(P<0.05). Patients with allergic rhinitis had a more severe endoscopic appearance, with a higher proportion of 4 degree, accounting for 75.0% of the total number of children with 4 degree under the nasopharyngoscopy, and only 25.0% of children without defined allergens. There was a significant difference between this two groups(P<0.05). Conclusion: Allergic rhinitis is closely related to adenoid hypertrophy, and the effect of allergen on the clinical manifestations of patients with adenoid hypertrophy should be emphasized.

[Clinical investigation of ultrasound-guided percutaneous nephrolithotomy accessed by SVOF-principle and two-step puncture techniques]

Objective: To evaluate the safety and effectiveness of ultrasound-guided percutaneous nephrolithotomy (PCNL) accessed by SVOF-principle and two-step puncture techniques. Methods: A total of 838 cases with upper urinary stones underwent percutaneous nephrolithotomy successfully accessed by ultrasound-guided between June 2007 and December 2015 at Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. Of all cases were divided in two groups: hydronephrosis calyces puncture group include 425 cases and SVOF-principle puncture group include 413 cases. The access establishment time, operation time, stone free rate (SFR), postoperative complications, and postoperative hospitalization time between the two groups we compared by t test or χ² test. Results: Statistically significant differences were observed between hydronephrosis calyces puncture group and SVOF-principle puncturegroup in the first access establishment time ((16.5±8.4) minutes vs. (11.2±5.9) minutes, t=3.931, P=0.013), one-stage SFR (74.3% vs. 85.7%, χ²=16.868, P=0.000), postoperative hospitalization time ((6.4±2.1) days vs. (4.8±1.8)days, t=4.574, P=0.000), transfusion rate (7.1% vs. 2.9%, χ²=8.027, P=0.006), and embolization rate (3.3% vs. 1.0%, χ²=5.390, P=0.020). There were no statistically significant differences in operation time, total SFR, postoperative fever and sever infection between these two groups (all P>0.05). In both two groups, no serious complications such as peripheral organ injury and death occurred. Conclusions: PCNL accessed guided by ultrasound with SVOF-principle and two-step puncture techniques has advantages of quick puncture location, high stone free rate, fewer complications and fast recovery. This technique is an effective and safe treatment option for upper urinary stones and deserved promotion and application in clinic.

[Influence of nicotinic acid adenine dinucleotide phosphate on autophagy in hypoxic cardiomyocytes of rats and its mechanism]

Objective: To investigate influence of nicotinic acid adenine dinucleotide phosphate (NAADP) on autophagy in hypoxic cardiomyocytes of rats and its mechanism. Methods: Five neonatal Sprague-Dawley rats were collected and sacrificed to harvest the hearts, and primary cardiomyocytes were separated for the following experiments. (1) Primary cardiomyocytes were collected and divided into normoxia group, hypoxia 9 h group, and hypoxia 9 h+ NAADP group according to random number table, with 5 wells in each group. Cells in normoxia group were cultured routinely in the constant temperature incubator at 37 ℃ for 9 hours. Cells in hypoxia 9 h group and hypoxia 9 h+ NAADP group were cultured in hypoxic incubator with volume fraction 94% nitrogen, 5% carbon dioxide, and 1% oxygen for 9 hours. Before hypoxia, cells in hypoxia 9 h+ NAADP group were dealt with final amount-of-substance concentration 10 μmol/L NAADP. Cell counting kit 8 was used to measure cell viability. (2) Primary cardiomyocytes were collected and divided into normoxia group, hypoxia 9 h group, hypoxia 9 h+ NAADP group, hypoxia 9 h+ tran-Ned-19 group, and hypoxia 9 h+ trans-Ned-19+ NAADP group according to the random number table, with 2 wells in each group. Cells in normoxia group were cultured routinely in the constant temperature incubator at 37 ℃ for 9 hours. And cells in the other 4 groups were cultured in hypoxic incubator as that in experiment (1) Before hypoxia, cells in hypoxia 9 h+ NAADP group were dealt with amount-of-substance concentration 10 μmol/L NAADP, cells in hypoxia 9 h+ tran-Ned-19 group were dealt with amount-of-substance concentration 1 μmol/L trans-Ned-19, and cells in hypoxia 9 h+ trans-Ned-19 + NAADP group were dealt with amount-of-substance concentration 10 μmol/L NAADP and 1 μmol/L trans-Ned-19. Protein expressions of microtubule associated protein 1 light chain 3-Ⅱ and P62 were detected by Western blotting. (3) Primary cardiomyocytes were collected and grouped as those in experiment (1). The lysosomal acidity was determined by immunofluorescence method. Data were processed with one-way analysis of variance and least-significant difference test. Results: (1) The cell viability in normoxia group was 1.114±0.024, which was significantly higher than 0.685±0.079 of cells in hypoxia 9 h group (P<0.01). The cell viability of hypoxia 9 h+ NAADP group was 0.886±0.061, which was obviously higher than that of cells in hypoxia 9 h group (P<0.05). (2) Expressions of microtubule-associated protein 1 light chain 3-Ⅱ and P62 of cells in hypoxia 9 h group were significantly higher than those of cells in normoxia group (P<0.01). Compared with those in hypoxia 9 h group, expression of P62 in hypoxia 9 h+ NAADP group was significantly decreased (P<0.01), while expression of microtubule-associated protein 1 light chain 3-Ⅱ did not change significantly (P>0.05). There were no significantly statistical difference in expressions of microtubule-associated protein 1 light chain 3-Ⅱ and P62 between hypoxia 9 h group and hypoxia 9 h+ trans-Ned-19 group (P>0.05). Compared with those of cells in hypoxia 9 h+ NAADP group, expression of P62 of cells in hypoxia 9 h+ trans-Ned-19+ NAADP group was obviously increased (P<0.01), while expression of microtubule-associated protein 1 light chain 3-Ⅱ did not change significantly (P>0.05). (3) The intensity of green fluorescence of cells in normoxia group was strong and co-localized well with red fluorescence, and internal environment of lysosome was with stronger acidity. The intensity of green fluorescence in cells of hypoxia 9 h group was significantly lower than that of cells in normoxia group, and acidity of internal environment of lysosome was weakened. The intensity of green fluorescence and acidity of internal environment of lysosome in hypoxia 9 h+ NAADP were significantly stronger than those of cells in hypoxia 9 h group, but significantly lower than those of cells in normoxia group. Conclusions: NAADP can improve myocardial cell viability through acidifying internal environment of lysosome of cardiomyocyte after hypoxia, promoting degradation of autophagosomes, reducing autophagic lysosomal accumulation, and repairing damaged autophagic flow.

[Relationship between one-stop CT spectral perfusion imaging parameters and expression of lymphatic microvessel density and vascular endothelial growth factor-C in axillary lymph nodes of rabbit VX2 breast cancer]

Objective: To analyze the correlation between quantitative parameters of one-stop spectral perfusion computed tomography imaging and the expression level of vascular endothelial growth factor-C(VEGF-C) and MLVD in metastatic lymph nodes of rabbit VX2 breast cancer. Methods: Thirty New Zealand purebred female rabbits were used to establish the lymph node metastasis model of rabbit VX2 breast cancer, one-stop spectral and perfusion CT imaging protocol was performed.The axillary lymph nodes were selected for corresponding image markers. The observed morphology of conventional HE staining and the EnVision method were used to quantitatively analyze VEGF-C expression and calculate MLVD.Pearson linear correlation was used to analyze the perfusion parameters of metastatic lymph node energy spectrum and the correlation of MLVD and VEGF-C expression. Results: Twenty-four experimental rabbits were successfully modeled and performed a one-stop CT scan on the 28th day. A total of 39 metastatic lymph nodes were included. The VEGF-C of metastatic lymph node was 20.0%±2.8%,and the MLVD was 12.5±3.5. There was a positive correlation between BF, AP(λHU), IC(VP), NIC(VP), VP(λHU) of metastatic lymph node and VEGF-C and MLVD (P<0.05). There was a positive correlation between lymph node IC(AP) and MLVD (P=0.027) and no correlation with VEGF-C expression (P=0.386).There was no correlation between BV, NIC(A)P and VEGF-C, MLVD(P>0.05). The correlation between VP(λHU) and MLVD was higher (r=0.448, P=0.001). Conclusions: One-stop CT spectral perfusion imaging quantitative parameters and pathological indicators have a good correlation, and it can reflect lymphatic vessel metastasis in lymph nodes.

Effects of organic zinc on tibia quality, mineral deposit, and metallothionein expression level of aged hens

The study aimed to determine the effects of methionine hydroxy analog chelate zinc on the tibia quality, mineral deposit, apparent retention of nutrients, and liver metallothionein (MT) expression level of aged laying hens. A total of 960 layers (Hy-Line Grey, 57 wk old) were randomly assigned into 4 groups, and each group had 8 replicates of 30 hens. During the first 2 wk, groups were fed a basal diet without extra zinc (Zn: 35.08 mg/kg). During the ensuing 14 wk, 4 levels of Zn (inorganic Zn: 80 mg/kg; organic Zn: 20, 40, 80 mg/kg) were added to the diet. The results indicated that both the Zn source and level did influence tibia strength and calcium (Ca) and Zn concentrations of tibia (P < 0.05), whereas there were no differences in the copper (Cu) and phosphorus (P) concentrations of the tibia and the tibia length (P > 0.05). Moreover, dietary supplementation with 40 or 80 mg/kg of organic Zn showed higher Zn and Ca concentrations in the tibia and higher tibia strength. The Cu concentration in the liver showed no difference among the 4 treatments, whereas the Zn concentration in the liver increased with the increasing Zn level. The apparent retention of P, iron (Fe), and manganese (Mn) was not affected by the Zn level or source (P > 0.05). However, the organic Zn group increased the apparent retention of Cu, Zn, Ca, crude protein (CP), and energy, and the group supplemented with 40 or 80 mg/kg of organic Zn obtained significant effects (P < 0.05). Moreover, dietary supplementation with 40 or 80 mg/kg organic Zn increased the MT mRNA expression of the liver at week 72, whereas 20 mg/kg of organic Zn decreased it (P < 0.05). In conclusion, this study suggested that an optimum dietary (40 mg/kg) organic Zn level plays a key role in promoting the apparent retention of minerals and nutrients, trace element deposit, and MT mRNA expression.

[Analysis of the clinical characteristics and efficacy of 20 cases of extranodal Rosai-Dorfman disease in head and neck]

Objective: To analyze the clinical characteristics and efficacy of extranodal Rosai-Dorfman disease in head and neck. Methods: Clinical and pathological features and follow-up of patients who were diagnosed as RDD at Beijing Tongren Hospital of Capital Medical University between May 2008 and November 2016 were analyzed retrospectively. Results: There were a total of 20 extranodal RDD patients in head and neck including 14 females and 6 males, aged from 27 to 86 years (mean 52.5 years). Nose (14 cases) and throat (5 cases) were most commonly involved organs and 5 patients had 2 or more organs involved. Diagnosis depends on biopsy. Histopathologically, the lesions of RDD were characterized by the presence of large histiocytes with emperipolesis. The large sinus histiocytes were positive for S-100 and CD68 protein staining. Diagnostic Errors in 13 patients and operations in all patients were happened. More than 1 operation was performed in 9 recurrence patients. Eight patients were treated by Glucocorticoids and immunosuppressive agents. All the patients were alive until Feb 2017. Conclusion: Extranodal RDD in head and neck is known as a rare benign idiopathic proliferative disease. Nose is the most common site involved, and recurrence easily. It is diagnosis depending on histopathological report. Operation is first choice in diagnosis and treatment now. Glucocorticoids and immunosuppressive agents are effective in recurrence patients.

[Role of hexokinase Ⅱ in the changes of autophagic flow in cardiomyocytes of mice with ischemia-hypoxia in vitro]

Objective: To investigate the role of hexokinase Ⅱ in the changes of autophagic flow in cardiomyocytes of mice with ischemia-hypoxia in vitro. Methods: The hearts of totally six male and female C57BL/6 mice aged from 1 to 2 days were isolated to culture primary cardiomyocytes which were used for the following experiments. (1) The cells were divided into 6 groups according to the random number table (the same grouping method below), i. e., normal control 3, 6, and 9 h groups and ischemia-hypoxia 3, 6, and 9 h groups, with 4 wells in each group. After being regularly cultured for 48 h with Dulbecco's modified Eagle medium/nutrient mixture F12 (DMEM/F12) medium (the same regular culture condition below), the cells in normal control 3, 6, and 9 h groups were cultured with replaced fresh DMEM/F12 medium for 3, 6, and 9 h, respectively, and the cells in ischemia-hypoxia 3, 6, and 9 h groups were cultured with replaced sugar-free serum-free medium in the low-oxygen incubator with a volume fraction of 1% oxygen and a volume fraction of 5% carbon dioxide at 37 ℃ (the same hypoxic culture condition below) for 3, 6, and 9 h, respectively. Cell viability was measured by the cell counting kit 8 (CCK-8) method. (2) The cells were grouped and treated the same as those in experiment (1), with 1 well in each group. Western blotting was used to detect the protein expressions of microtubule-associated protein 1 light chain 3 Ⅰ (LC3Ⅰ), LC3Ⅱ, p62, and hexokinase Ⅱ. (3) The cells were divided into normal control group, simple ischemia-hypoxia 9 h group, and ischemia-hypoxia 9 h+ 2-deoxyglucose (2-DG) group, with 4 wells in each group. After a regular culture for 48 h, the cells in normal control group were cultured with replaced fresh DMEM/F12 medium for 9 h; the cells in simple ischemia-hypoxia 9 h group were replaced with sugar-free serum-free medium, and the cells in ischemia-hypoxia 9 h+ 2-DG group were replaced with sugar-free serum-free medium in which 2-DG was dissolved in a concentration of 10 mmol/L (20 μmol), and then they were cultured with hypoxia for 9 h. Cell viability was measured by CCK-8 method. (4) The cells were grouped and treated the same as those in experiment (3), with 1 well in each group. Western blotting was used to detect the protein expressions of LC3Ⅰ, LC3Ⅱ, and p62. (5) The cells were grouped and treated the same as those in experiment (3), with 2 wells in each group. Transmission electron microscope was used to observe autophagosomes/autolysosomes in cardiomyocytes. (6) The cells were divided into normal control group, simple ischemia-hypoxia 9 h group, ischemia-hypoxia 9 h+ hexosinase Ⅱ small interfering RNA1 (HK-ⅡsiRNA1) group, and ischemia-hypoxia 9 h+ HK-ⅡsiRNA2 group, with 4 wells in each group. The cells in normal control group and simple ischemia-hypoxia 9 h group were regularly cultured for 48 h, and the cells in ischemia-hypoxia 9 h+ HK-ⅡsiRNA1 group and ischemia-hypoxia 9 h+ HK-ⅡsiRNA2 group were respectively transfected with 200 nmol/L HK-ⅡsiRNA1 and HK-ⅡsiRNA2 and then also cultured for 48 h. The cells in normal control group were cultured with replaced fresh DMEM/F12 medium for 9 h, and the cells in simple ischemia-hypoxia 9 h group, ischemia-hypoxia 9 h+ HK-ⅡsiRNA1 group, and ischemia-hypoxia 9 h+ HK-ⅡsiRNA2 group were cultured with replaced sugar-free serum-free medium and hypoxia for 9 h. Cell viability was measured by CCK-8 method. (7) The cells were grouped and treated the same as those in experiment (6), with 1 well in each group. Western blotting was used to detect the protein expressions of LC3Ⅰ, LC3Ⅱ, p62, and hexokinase Ⅱ. Except for experiment (5), each experiment was repeated 3 times. Data were processed with one-way analysis of variance and lest significant difference t test, and Bonferroni correction. Results: (1) The viabilities of cardiomyocytes in ischemia-hypoxia 3, 6, and 9 h groups were 0.450±0.022, 0.385±0.010, and 0.335±0.015, respectively, which were significantly lower than 0.662±0.026, 0.656±0.028, and 0.661±0.021 of the corresponding normal control 3, 6, and 9 h groups, respectively (t=6.21, 9.12, 12.48, P<0.01). (2) Compared with those of corresponding normal control 3, 6, and 9 h groups, the LC3Ⅱ/Ⅰ ratio and protein expressions of p62 and hexokinase Ⅱ in cardiomyocytes of ischemia-hypoxia 3, 6, and 9 h groups were significantly increased (t(3 h)=16.15, 10.99, 5.30, t(6 h)=6.79, 10.42, 9.42, t(9 h)=15.76, 16.51, 7.20, P<0.05 or P<0.01). (3) The viability of cardiomyocytes in simple ischemia-hypoxia 9 h group was 0.353±0.022, which was significantly lower than 0.673±0.027 of normal control group (t=9.29, P<0.01). The viability of cardiomyocytes in ischemia-hypoxia 9 h+ 2-DG group was 0.472±0.025, which was significantly higher than that of simple ischemia-hypoxia 9 h group (t=3.60, P<0.05). (4) Compared with those of normal control group, the LC3Ⅱ/Ⅰ ratio and protein expression of p62 in cardiomyocytes of simple ischemia-hypoxia 9 h group were significantly increased (t=9.45, 8.40, P<0.01). Compared with those of simple ischemia-hypoxia 9 h group, the LC3Ⅱ/Ⅰratio and protein expression of p62 in cardiomyocytes of ischemia-hypoxia 9 h+ 2-DG group were significantly decreased (t=4.39, 4.74, P<0.05). (5) In cardiomyocytes of normal control group, only single autophagosome/autolysosome with bilayer membrane structure was observed. Compared with that of normal control group, the number of autophagosome/autolysosome with bilayer membrane structure in cardiomyocytes of simple ischemia-hypoxia 9 h group was increased significantly. Compared with that of simple ischemia-hypoxia 9 h group, the number of autophagosome/autolysosome with bilayer membrane structure in cardiomyocytes of ischemia-hypoxia 9 h+ 2-DG group was significantly decreased. (6) The viability of cardiomyocytes in simple ischemia-hypoxia 9 h group was 0.358±0.023, which was significantly lower than 0.673±0.026 in normal control group (t=9.12, P<0.01). The viabilities of cardiomyocytes in ischemia-hypoxia 9 h+ HK-ⅡsiRNA1 group and ischemia-hypoxia 9 h+ HK-ⅡsiRNA2 group were 0.487±0.027 and 0.493±0.022, respectively, which were significantly higher than the viability in simple ischemia-hypoxia 9 h group (t=3.63, 4.28, P<0.05). (7) Compared with those of normal control group, the LC3Ⅱ/Ⅰratio and protein expressions of p62 and hexokinase Ⅱ in cardiomyocytes of simple ischemia-hypoxia 9 h group were significantly increased (t=6.08, 6.31, 4.83, P<0.05 or P<0.01). Compared with those of simple ischemia-hypoxia 9 h group, the LC3Ⅱ/Ⅰ ratio and protein expressions of p62 and hexokinase Ⅱ in cardiomyocytes of ischemia-hypoxia 9 h+ HK-ⅡsiRNA1 group and ischemia-hypoxia 9 h+ HK-ⅡsiRNA2 group were significantly decreased (t=5.10, 7.76, 15.33, 4.17, 8.42, 12.11, P<0.05 or P<0.01). Conclusions: Ischemia-hypoxia upregulates the expression level of hexokinase Ⅱ protein in mouse cardiomyocytes cultured in vitro, which decreases the viability of cardiomyocytes by impairing autophagic flow. To inhibit the activity of hexokinase Ⅱ or its expression can alleviate the ischemia-hypoxia damage of cardiomyocytes.

MicroRNA-182 suppresses clear cell renal cell carcinoma migration and invasion by targeting IGF1R

The purpose of our study was aimed to determine the functional role of microRNA (miR)-182 in clear cell renal cell carcinoma (ccRCC) and try to clarify its underlying molecular mechanism. Expression of miR-182 in both cancer and peripheral blood samples was analyzed by quantitative real-time PCR (qRT-PCR). Human RCC line Caki-1 cells were transfected with miR-182 mimic, miR-182 inhibitor, or negative controls, and then the cell viability, colony-formation ability, migration, and invasion assay were determined. Luciferase reporter assay, qRT-PCR and Western blotting were used to determine whether insulin-like growth factor 1 receptor (IGF1R) was a target of miR-182. Further, small interfering RNA (siRNA) against IGF1R was co-transfected with miR-182 inhibitor into cells, and then the effects on migration and invasion were assessed. MiR-182 was down-regulated in both cancer and blood samples compared to the matched non-tumor adjacent tissues and healthy volunteers, respectively (both P<0.05). Compared to the control group, cell viability, colony-forming ability, and numbers of migrated and invaded cells were significantly decreased by transfection with miR-182 mimic but were markedly increased by miR-182 inhibitor (all P < 0.05). Luciferase reporter assay confirmed that IGF1R was a target gene of miR-182, and IGF1R was negatively regulated by miR-182. Co-transfection of miR-182 inhibitor with si-IGF1R reversed the effect of miR-182 inhibitor on the migration and invasion of the cells. MiR-182 functions as an anti-oncogene in ccRCC, and miR-182-mediated inhibition of cell migration and invasion might be through directly targeting IGF1R.

Optimal expression and purification of sapelovirus A structural protein VP1, and its immunogenicity in mice

Sapelovirus A (SV-A) is a positive-sense single-stranded RNA virus which is associated with acute diarrhea, pneumonia and reproductive disorders. The virus capsid is composed of four proteins, and the functions of the structural proteins are unclear. In this study, we expressed SV-A structural protein VP1 and studied its antigenicity and immunogenicity. SDS-PAGE analysis revealed that the target gene was expressed at high levels at 0.6 mM concentration of IPTG for 24 h. The mouse polyclonal antibody against SV-A VP1 protein was produced and reached a high antiserum titer (1: 2,048,000). Immunized mice sera with the recombinant SV-A VP1 protein showed specific recognition of purified VP1 protein by western blot assay and could recognize native SV-A VP1 protein in PK-15 cells infected with SV-A by indirect immunofluorescence assay. The successfully purified recombinant protein was able to preserve its antigenic determinants and the generated mouse anti-SV-A VP1 antibodies could recognize native SV-A, which may have the potential to be used to detect SV-A infection in pigs.

Complete genome sequencing of three human clinical isolates of Staphylococcus caprae reveals virulence factors similar to those of S. epidermidis and S. capitis

Background

Staphylococcus caprae is an animal-associated bacterium regarded as part of goats’ microflora. Recently, S. caprae has been reported to cause human nosocomial infections such as bacteremia and bone and joint infections. However, the mechanisms responsible for the development of nosocomial infections remain largely unknown. Moreover, the complete genome sequence of S. caprae has not been determined.

Results

We determined the complete genome sequences of three methicillin-resistant S. caprae strains isolated from humans and compared these sequences with the genomes of S. epidermidis and S. capitis, both of which are closely related to S. caprae and are inhabitants of human skin capable of causing opportunistic infections. The genomes showed that S. caprae JMUB145, JMUB590, and JMUB898 strains contained circular chromosomes of 2,618,380, 2,629,173, and 2,598,513 bp, respectively. JMUB145 carried type V SCCmec, while JMUB590 and JMUB898 had type IVa SCCmec. A genome-wide phylogenetic SNP tree constructed using 83 complete genome sequences of 24 Staphylococcus species and 2 S. caprae draft genome sequences confirmed that S. caprae is most closely related to S. epidermidis and S. capitis. Comparative complete genome analysis of eight S. epidermidis, three S. capitis and three S. caprae strains revealed that they shared similar virulence factors represented by biofilm formation genes. These factors include wall teichoic acid synthesis genes, poly-gamma-DL-glutamic acid capsule synthesis genes, and other genes encoding nonproteinaceous adhesins. The 17 proteinases/adhesins and extracellular proteins known to be associated with biofilm formation in S. epidermidis were also conserved in these three species, and their biofilm formation could be detected in vitro. Moreover, two virulence-associated gene clusters, the type VII secretion system and capsular polysaccharide biosynthesis gene clusters, identified in S. aureus were present in S. caprae but not in S. epidermidis and S. capitis genomes.

Conclusion

The complete genome sequences of three methicillin-resistant S. caprae isolates from humans were determined for the first time. Comparative genome analysis revealed that S. caprae is closely related to S. epidermidis and S. capitis at the species level, especially in the ability to form biofilms, which may lead to increased virulence during the development of S. caprae infections.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-5185-9) contains supplementary material, which is available to authorized users.