Factors Influencing Viral Clearance in Mild COVID-19 and Clinical Characteristics of Asymptomatic Patients.

BACKGROUND: The outbreak of coronavirus disease (COVID-19) has become a global public health emergency. OBJECTIVE: To evaluate the characteristics and outcomes of patients with COVID-19 in Anhui and to identify predictors of viral clearance. METHODS: We retrospectively analyzed the data collected from discharged patients with laboratory-confirmed SARS-CoV-2 infections. We compared clinical features between viral clearance and viral persistence, and evaluated factors associated with SARS-CoV-2 shedding using multiple linear regression. RESULTS: Among the 83 patients involved in the study, the median age was 43 years, while 60.2% were male, 35.4% had comorbidities, and the mortality was zero. The median time from illness onset to admission was 5 days (interquartile range (IQR), 2-7 days), and the median time from the illness onset to SARS-CoV-2 RNA detection was 16 days (IQR, 13-18 days). The factors influencing viral clearance were as follows: (1) delayed admission (beta 1.057, 95% CI 0.810-1.304; p ≤ 0.001) and (2) underlying comorbidities (beta 1.907, 95% CI 0.198-3.616; p = 0.029). No significant differences were observed in the length of stay (p = 0.246) and pneumonia between asymptomatic and symptomatic patients based on computed tomography (CT) (p = 0.124). CONCLUSIONS: Delayed admission and underlying comorbidities may effectively predict SARS-CoV-2 RNA clearance. For those infected with SARS-CoV-2, even asymptomatic patients without any clinical symptoms should be traced and isolated. This practice may reduce the spread of SARS-CoV-2 and slow the COVID-19 pandemic caused by the virus. Clinical Trial Registration Number: This trial is registered with 2020-051.

Therapeutic effects of mesenchymal stem cell-derived microvesicles on pulmonary arterial hypertension in rats.

AIM: Microvesicles (MVs) are nanoscale membrane fragments released from virtually all cell types upon activation or apoptosis, and may contribute to the beneficial effects of stem cell therapy. In this study, we investigated the therapeutic effects of mesenchymal stem cell (MSC) derived MVs (MSC-MVs) on pulmonary artery hypertension (PAH) in rats. METHODS: MSC-MVs were isolated from rat bone marrow MSCs that were cultured in a serum-free conditioned medium. Transmission electron microscopy (TEM), flow cytometry and nanoparticle tracking analysis (NTA) were used to characterize the MVs. Adult SD rats were injected with monocrotaline (50 mg/kg, sc) to induce PAH. Three weeks later, the rats were intravenously injected with MSCs, MSC-MVs or saline for 2 weeks. At the end of treatments, the hemodynamic parameters and pathological right ventricular and pulmonary arterial remodeling were analyzed in each group. RESULTS: The MSC-MVs showed general morphologic characteristics of MVs and expressed annexin V and CD29 markers under TEM, and their size ranged from 40 to 300 nm. Intravenous injection of MSC-MVs or MSCs significantly ameliorated the mean pulmonary artery pressure (mPAP) and mean right ventricle pressure (mRVP) in PAH rats. Furthermore, intravenous injection of MSC-MVs or MSCs significantly decreased the right ventricle (RV) hypertrophy and pulmonary arteriole area index (AI) and thickness index (TI) in PAH rats. CONCLUSION: Intravenous injection of MSC-MVs or MSCs produces similar beneficial effects for treating PAH, and our results provide a basis for cell-free approach in stem cell therapy.

Functionalized magnetic iron oxide (Fe3O4) nanoparticles for capturing gram-positive and gram-negative bacteria.

The development of nanotechnology in biology and medicine has raised the need for conjugation of nanoparticles (NPs) to biomolecules. In this study, magnetic and functionalized magnetic iron oxide nanoparticles were synthesized and used as affinity probes to capture Gram-positive/negative bacteria. The morphology and properties of the magnetic NPs were examined by transmission electron microscopy, Fourier transform infrared spectroscopy, and zeta potential measurements. Furthermore, this study investigated the interaction between functionalized magnetic nanoparticles and Gram positive/negative bacteria. The positively and negatively charged magnetic nanoparticles include functionalities of Fe3O4, SiO2, TiO2, ZrO2, poly ethyleneimine (PEI) and poly acrylic acid. Their capture efficiencies for bacteria were investigated based on factors such as zeta potential, concentration and pH value. PEI particles carry a positive charge over a range of pH values from 3 to 10, and the particles were found to be an excellent candidate for capturing bacteria over such pH range. Since the binding force is mainly electrostatic, the architecture and orientation of the functional groups on the NP surface are not critical. Finally the captured bacteria were analyzed using matrix-assisted laser desorption/ionization mass spectrometry. The minimum detection limit was 10(4) CFU/mL and the analysis time was reduced to be less than 1 hour. In addition, the detection limit could be reduced to an extremely low concentration of 50 CFU/mL when captured bacteria were cultivated.

Intestinal permeability of forskolin by in situ single pass perfusion in rats.

The intestinal permeability of forskolin was investigated using a single pass intestinal perfusion (SPIP) technique in rats. SPIP was performed in different intestinal segments (duodenum, jejunum, ileum, and colon) with three concentrations of forskolin (11.90, 29.75, and 59.90 µg/mL). The investigations of adsorption and stability were performed to ensure that the disappearance of forskolin from the perfusate was due to intestinal absorption. The results of the SPIP study indicated that forskolin could be absorbed in all segments of the intestine. The effective permeability (P (eff)) of forskolin was in the range of drugs with high intestinal permeability. The P (eff) was highest in the duodenum as compared to other intestinal segments. The decreases of P (eff) in the duodenum and ileum at the highest forskolin concentration suggested a saturable transport process. The addition of verapamil, a P-glycoprotein inhibitor, significantly enhanced the permeability of forskolin across the rat jejunum. The absorbed fraction of dissolved forskolin after oral administration in humans was estimated to be 100 % calculated from rat P (eff). In conclusion, dissolved forskolin can be absorbed readily in the intestine. The low aqueous solubility of forskolin might be a crucial factor for its poor oral bioavailability.

[Effect of liposuction on adipokines, inflammatory markers and insulin resistance].

OBJECTIVE: To study the effect of large-volume liposuction on adipokines, inflammatory markers and insulin resistance and its significance. METHODS: The levels of serum adiponectin, resistin, IL-6, TNF-alpha, CRP and insulin sensitivity were measured pre- and 3 months postoperatively in 16 consecutive patients undergoing liposuction. RESULTS: The adiponectin postoperative [(5.56 +/- 1.03) ng/ml] was significantly higher than the preoperative [(6.54 +/- 1.27) ng/ml] (P<0.05); the resistin postoperative [(6.30 +/- 3.25) pg/ml] is significantly lower than the preoperative [(5.18 +/- 2.28) pg/ml] (P<0.05); the insulin sensitivity postoperative (-3.78 +/- 0.39) significantly increased compared to the preoperative (-3.48 +/- 0.32, P<0.05); the TNF-alpha postoperative [(0.19 +/- 0.02) pg/ml] significantly increased compared to the preoperative [(0.23 +/- 0.03) pg/ml, P<0.01]; the postoperative IL-6 [(0.27 +/- 0.04) pg/ml] was similar to the preoperative [(0.31 +/- 0.06) pg/ml, P >0.05]; the postoperative CRP [(8.03 +/- 6.01) mg/L] was not significantly different with the preoperative [(7.28 +/- 6.21) mg/L, P>0.05]. CONCLUSIONS: Large-volume liposuction has good effect on insulin resistance and adipokines.

Combination excision and liposuction in a single-stage treatment of various skin disorders.

OBJECTIVES: The repair of skin defects resulting from the excision of large skin disorders is always challenging for surgeons as many methods have varied disadvantages. Therefore, we attempt to overcome frequent disadvantages of other surgical methods in repairing skin defects with the help of liposuction. METHODS: Before excision of skin disorders, liposuction was performed in regions where they were located followed by complete excision. The sliding flaps on both sides of the defect created by liposuction were pulled together to cover the defect. In our study, 40 skin disorders located on the upper arm, thigh, and trunk were treated by this technique. RESULTS: Forty skin disorders were excised and resulting skin defects were repaired in one stage by the surrounding sliding flaps without wound dehiscence, infection, incision edge necrosis, sensory deficit, or severe scar recurrence. The regions of liposuction presented a harmonious result and simultaneously the body contour was well-balanced. CONCLUSION: Some large skin disorders at sites rich in subcutaneous fat can be treated in one stage by combining excision and liposuction with good functional and esthetic outcomes with few complications. Although the indications for this technique are limited, it is really a good option for appropriate cases.

Reconstruction of large hypertrophic scar on trunk and thigh by means of liposuction technique.

OBJECTIVE: Hypertrophic scars on trunk and thigh are less important in function and appearance than those on face, neck, hand, foot and joint. However, patients suffer itching, pain and disfiguration. Thus far, neither non-surgical nor surgical methods treat these scars perfectly. This study reports on the application of liposuction technique to reconstruct these scars and reviews the outcomes. METHOD: Between March 2000 and March 2008, we treated 26 hypertrophic scars on trunk and thigh (20 patients) using liposuction. Tumescent liquids were infiltrated and liposuction was performed in the areas of trunk and thigh where the scars located. Following scar excision, defects were covered by sliding flap created by liposuction. Incisions were closed without tension. RESULTS: Twenty-six hypertrophic scars were reconstructed in one stage by flaps of similar texture and colour in areas around the scars without wound dehiscence, infection, skin necrosis, sensory deficit, haematoma and seroma. The contours of liposuction areas were natural and even. CONCLUSION: Large hypertrophic scar at sites rich in subcutaneous fat such as trunk and thigh can be reconstructed in one stage by liposuction technique, which is easy, safe, effective and economic. Although indications of liposuction scar reconstruction are strict, it is indeed a better option for appropriate cases.

[Trilobate technique, a new principal to repair cleft lip].

OBJECTIVE: To develop a new method for reparation of cleft lip, and to evoke more colleagues for advance practices and study, in order to determine her indication and contraindication as soon as possible. METHODS: 48 cases were included into this study. Trilobate flap were designed in floor of nose and lip area in cleft side, rotate two of the three flaps upwards, respectively to elevate the tip of nose, and to reconstruct the floor of nose. As for the left flap, it was derived transversally to opposing side, sutured with the flap of non-cleft-side. RESULTS: With this technique, less tissue was lost, better vertical lengthening and good formed cuspids-bow was achieved, and the scar was a parallel line being symmetry to the philtrum column opposite. Meanwhile, because the tension was mainly located in the area where there was no mini flaps, the blood supply was good enough, rarely occur any necrosis in the tip of flaps. All cases in this study obtained perfect healing, with good appearance at nostrils and floor of nose. CONCLUSIONS: In use of the method of trilobate flap, we can draw down the peak of the cuspids bow effectually, hence avoid the addition cut in the lower part of the lip, decrease the scar on skin, as well as nice reconstruction of floor of nose, philtrum column and nostril. Because lack of long term study, we evoke more colleagues for cooperation in advance study.

Intramuscular delivery of rAAV-mediated kallikrein gene reduces hypertension and prevents cardiovascular injuries in model rats.

AIM: The overexpression of the human tissue kallikrein (HK) gene can reduce blood pressure and ameliorate the secondary syndromes associated with hypertension in animal models. The current study was designed to investigate hypotensive effect of intramuscular delivery of HK gene. METHODS: We generated an recombinant adeno-associated virus (rAAV) vector expressing human tissue kallikrein under the control of a cytomegalovirus promoter and administered the rAAV-HK vector to a spontaneously hypertensive rat model at a dose of 1 x 10(10) virons/rat through intramuscular injection. RESULTS: A persistent, high-level expression of HK post-gene delivery was confirmed by ELISA. The systolic blood pressure in the rats receiving rAAV-LacZ and saline increased from 171.3 mmHg to 182.3 mmHg 28 weeks' post injection. In contrast, the delivery of the HK gene by AAV vectors attenuated the increase of the systolic blood pressure in the treated group. The systolic blood pressure was only slightly lowered (from a level of 174 mmHg to 170.5 mmHg) post-vector administration. The difference in blood pressure between the treated group and the control groups is statistically significant at 12.6 mmHg. The hypotensive effect of rAAV-HK persisted until the end of the testing period. In addition, a significant amelioration of cardiovascular hypertrophy, renal injury, and collagen depositions in the rAAV-HK-treated animals were also observed. CONCLUSION: All the effects are comparable with those of intravenous delivery. Therefore, the intramuscular administration of rAAV-HK may be used in gene therapy for hypertension.

Cytochrome p450 epoxygenase promotes human cancer metastasis.

Cytochrome P450 (CYP) epoxygenases convert arachidonic acid to four regioisomeric epoxyeicosatrienoic acids (EET), which exert diverse biological activities in a variety of systems. We previously reported that the CYP2J2 epoxygenase is overexpressed in human cancer tissues and cancer cell lines and that EETs enhance tumor growth, increase carcinoma cell proliferation, and prevent apoptosis of cancer cells. Herein, we report that CYP epoxygenase overexpression or EET treatment promotes tumor metastasis independent of effects on tumor growth. In four different human cancer cell lines in vitro, overexpression of CYP2J2 or CYP102 F87V with an associated increase in EET production or addition of synthetic EETs significantly induced Transwell migration (4.5- to 5.5-fold), invasion of cells (3- to 3.5-fold), cell adhesion to fibronectin, and colony formation in soft agar. In contrast, the epoxygenase inhibitor 17-ODYA or infection with the antisense recombinant adeno-associated viral vector (rAAV)-CYP2J2 vector inhibited cell migration, invasion, and adhesion with an associated reduction in EET production. CYP overexpression also enhanced metastatic potential in vivo in that rAAV-CYP2J2-infected MDA-MB-231 human breast carcinoma cells showed 60% more lung metastases in athymic BALB/c mice and enhanced angiogenesis in and around primary tumors compared with control cells. Lung metastasis was abolished by infection with the antisense rAAV-CYP2J2 vector. CYP epoxygenase overexpression or EET treatment up-regulated the prometastatic matrix metalloproteinases and CD44 and down-regulated the antimetastatic genes CD82 and nm-23. Together, these data suggest that CYP epoxygenase inhibition may represent a novel approach to prevent metastasis of human cancers.

[Arachidonic acid epoxygenases and their metabolites promote angiogenesis].

OBJECTIVE: To investigate the angiogenetic effects of endogenous and exogenous epoxyeicosatrienoic acids (EET) and the relevant signaling mechanisms involved. METHODS: Bovine aortic endothelial cells (BAEC) were incubated with synthetic EETs or infected with recombinant adeno-associated viruses (rAAV) containing CYP2C11-CYPOR, CYP2J2 or CYP102 F87V mutant to increase endogenous expression levels of EETs. BAEC proliferation measured by cell counting and chromatometry, migration assessed by transwell analysis, and capillary formation determined by chicken embryo chorioallantoic membrane assays (CAM) and tube formation tests on matrigel and angiogenesis were analysed in vivo. The potential involvement of various signaling pathways were explored using selective inhibitors. RESULTS: Transfection with rAAV-2C11OR, rAAV-2J2 or rAAV-F87V promoted BAEC proliferation, migration, and capillary tubule formation. However, the effects of EETs on proliferation, migration and capillary tubule formation were attenuated by inhibitors of mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3 kinase)/Akt pathways, and partially attenuated by endothelial nitric oxide synthase (eNOS) inhibitor, but not by a protein kinase C inhibitor. In a rat ischemic hind limb model, rAAV-mediated epoxygenase transfection induced angiogenesis. CONCLUSIONS: Arachidonic acid epoxygenase and its metabolites can promote angiogenesis through activating MAPK and PI3 kinase/Akt signaling pathways, and to some extent, the eNOS pathway, and the angiogenic effects may provide protection to ischemic tissues.

[Study on the distribution of serum homocysteine and on multi-stepwise regression analysis of the associated factors in the population of community areas in Wuhan].

OBJECTIVE: To study the serum homocysteine (Hcy) distribution and characteristics in different sex and age groups in the community residents in Wuhan, and to analyse its associated factors with multi-stepwise regression analysis. METHODS: The population under study was from three community areas in Wuhan. Demographic distribution and the correlation with other risk factors of serum Hcy were analyzed statistically. RESULTS: (1) Geometric mean of serum Hcy was 14.43 micromol/L in males and 10.89 micromol/L in females with P <0.001. (2) Hcy of per age level in males was also higher (P <0.001). (3) The prevalence rate of hyperhomocysteinemia was 23.94% in the general population in Wuhan. The prevalence rate of hyperhomocysteinemia in males was 2.62 times higher than in females. (4) Multi-stepwise regression analysis showed that Hcy had different affecting factors in males and females. The affecting factors of Hcy in males were daily cigarettes smoking, urine micro-albumin (UMALB) and times of exercise per week. The affecting factors of Hcy in females were duration of exercise each time, weight, triglyceride (TG), high-density lipoprotein (HDL), urine micro-albumin (UMALB) and age. CONCLUSIONS: (1) Hcy at the population level was significantly different by sex and age. (2) Population living in the community in Wuhan had a higher serum level and prevalence rate of Hcy comparing to some other cities in China and even in developed countries. (3) The important affecting factors of Hcy in population also showed sex difference, unlike the reports from other countries or other areas in China. Serum Hcy seemed to be affected by environmental and other factors.