Serum Vitamin D Level in Overweight Individuals and Its Correlation With the Incidence of Non-alcoholic Fatty Liver Disease.

In this study, we investigated the serum vitamin D level in overweight individuals and its correlation with the incidence of nonalcoholic fatty liver disease (NAFLD). Between May 2020 and May 2021, the Department of Gastroenterology at the People's Hospital of Henan University of Traditional Chinese Medicine treated a total of 321 outpatients and inpatients with NAFLD, who were included in the NAFLD group, while 245 healthy age- and gender-matched individuals were included in the control group. All the data were collected for the relevant indices, including fasting plasma glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, alanine transaminase, and 25-hydroxy vitamin D (25[OH]D. The patients with NAFLD were divided into the normal BMI group, the overweight group, and the obese group, according to the body mass index, and the 25(OH)D levels were compared between the different groups. Spearman's correlation analysis was performed to analyze the correlation between the serum 25(OH)D level and NAFLD. Regarding the serum 25 (OH)D level, it was lower in the NAFLD group than in the control group ([18.36 + 1.41] µg/L vs [22.33 + 2.59] µg/L, t = ?5.15, P<0.001), and was lower in the overweight group than in the normal group ([18.09 ± 5.81] µg/L vs [20.60 ± 4.16] µg/L, t = 0.26, P = 0.041). The serum 25(OH)D level was thus negatively correlated with the incidence of NAFLD in overweight individuals (r = 0.625, P<0.05). In conclusion, the level of 25(OH)D decreased in patients with NAFLD with increasing BMI (normal, overweight, obese). Keywords: Nonalcoholic fatty liver disease, Vitamin D.

[Research progress of non-biological artificial liver support system therapy for paitents with liver failure].

Liver failure progresses quickly with high mortality. Non-biological artificial liver support system therapy is one of the important treatments for patients with liver failure. The basic techniques of non-biological artificial liver support system therapy include plasma exchange, plasma adsorption and continuous renal replacement therapy. In this paper, the effect and choice of these basic techniques, the treatment timing, the possible patients who may benefit, and the existing problems are summarized and discussed. We hope to provide a reference for the rational use of non-biological artificial liver support system therapy in clinical practice.

The efficacy and safety of pirfenidone in the treatment of HPS-related pulmonary fibrosis and Idiopathic pulmonary fibrosis: a systematic review and meta-analysis.

OBJECTIVE: The incidence of idiopathic pulmonary fibrosis is increasing year by year in the world, which has a greater impact on the quality of life of patients. In the past, symptomatic treatment was used in clinical practice, but the overall effect is still not good. Multiple clinical studies have demonstrated the efficacy of pirfenidone in the treatment of idiopathic pulmonary fibrosis; however, adverse reactions have been reported. We, therefore, systematically evaluated the effectiveness and safety of pirfenidone in patients with idiopathic pulmonary fibrosis. PATIENTS AND METHODS: Relevant studies were retrieved from the Embase, PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature (CBM), Wanfang and Weipu databases between January 1999 and May 2020, including the keywords "pirfenidone" and "idiopathic pulmonary fibrosis", were included in our systematic review. Review Manager 5.4 software was used for data synthesis, and analyses of publication bias and sensitivity. RESULTS: Our systematic review included 13 studies involving a total of 13247 patients with idiopathic pulmonary fibrosis. Pirfenidone was associated with reduced declines in vital capacity (VC) and forced vital capacity (FVC) from baseline in patients with hermansky-pudlak syndrome (HPS)-related pulmonary fibrosis and to moderate idiopathic pulmonary fibrosis (IPF). Pirfenidone treatment was associated with lower reductions in FVC, lower reductions in 6-minute walking test distance, lower decreases in minimum oxygen saturation during the 6-minute walking test, lower all-cause death, lower relative risk of IPF-related death and increased progression-free survival compared to placebo. Progression-free survival was significantly longer in the pirfenidone group. The incidence of gastrointestinal, skin, nervous system, and liver function-related adverse events was significantly higher in the pirfenidone group compared to the control group. CONCLUSIONS: Pirfenidone has efficacy in delaying the progression of idiopathic pulmonary fibrosis. Pirfenidone is well-tolerated by the majority of patients; however, mild adverse reactions related to the gastrointestinal tract, skin, nervous system, and liver function are common. Overall, Pirfenidone may be an effective and well-tolerated treatment option for idiopathic pulmonary fibrosis.

[Application of ultra-short echo time-T2* component analysis technology in monitoring morphological and biochemical changes of achilles tendon in amateur marathon athletes].

Objective: To explore the value of ultra-short echo time (UTE)-T2* component analysis techniques in dynamic monitoring the morphological and biochemical changes in amateur marathon athletes' achilles tendon before and after the marathon. Methods: Twenty-nine amateur marathon runners were recruited between October 2020 and March 2021 in Zhuhai City, Guangdong Province, including 25 males and 4 females, aged from 24 to 50 (40±6) years old. All volunteers underwent bilateral achilles tendon MRI examination 1 week before the marathon, 48 hours after the race, and 1 month after the race. The shape and signal of the achilles tendon were evaluated by routine T1-weighted, proton density weighted with fat saturation sequence and different echo time (TE) UTE sequence, and the changes of achilles tendon after running was quantitatively analyzed by UTE-T2* sequence. The values of single-component analysis (T2*M), short T2* components (T2*S), and long T2* components (T2*L) and Fraction values were obtained using UTE-T2* sequence. The value of the whole achilles tendon was measured on the sagittal images of achilles tendon, and the Achilles tendon was equally divided into three subregions [muscle-tendon junction (MTJ), middle (MID), and insertion (INS)]. The region of interest was delineated by two radiologists independently. The intra-group correlation coefficient (ICC) was used to evaluate the consistency of the data measured by two radiologists. Nonparametric Friedman M test was used to compare the differences of T2*M, T2*S, T2*L and Fraction values in different time points and different subregions. Wilcoxon rank-sum test was used to compare the difference between 48 h post-race and pre-race T2*S values (ΔT2*S) of different distance, different running posture, different pace and different amount of training, in which ΔT2*S equals the T2*S value of 48 h post-race minus the T2*S value of pre-race. Results: On the sequence of short TE (TE≤0.6 ms), achilles tendinopathy can manifest as scattered punctate hypointensity in areas of high signal intensity. The two radiologists showed a good consistency in measuring the T2*M, T2*S, T2*L and Fraction values of the achilles tendon, and the ICC values ​​were 0.96, 0.94, 0.83 and 0.94, respectively. The T2*s values was significantly higher in the whole Achilles tendon, MTJ and MID segment at 48 h post-exercise compared to pre-exercise, and decreased after 1 month of exercise, [0.49 (0.45, 0.59) vs 0.54 (0.49, 0.59) vs 0.53 (0.49, 0.57), 0.48 (0.44, 0.54) vs 0.53 (0.47, 0.58) vs 0.50 (0.46, 0.57), 0.48 (0.43, 0.58) vs 0.54 (0.47, 0.59) vs 0.52 (0.46, 0.57); respectively, all P<0.05]. The changes in T2*M, T2*L and Fraction values are not statistically significant (all P>0.05). In different running gestures, the ΔT2*S of achilles tendon who using the postures of front-middle feet is higher than that using the postures of back feet (0.03(-0.05, 0.07) vs -0.03(-0.17, 0.11), P=0.001). Conclusion: The Bi-component analysis of UTE-T2* technology is superior to single component analysis in monitoring the dynamic changes of achilles tendon before and after exercise, and T2*S is a more sensitive sequence to evaluate the subtle changes in the chemical composition of achilles tendon.

Macromolecular fraction (MMF) from 3D ultrashort echo time cones magnetization transfer (3D UTE-Cones-MT) imaging predicts meniscal degeneration and knee osteoarthritis.

OBJECTIVE: Meniscal degeneration is strongly associated with osteoarthritis (OA). We aimed to evaluate a 3D ultrashort-echo-time Cones magnetization transfer (UTE-Cones-MT) sequence for quantification of macromolecular fraction (MMF) and MT ratio (MTR) in menisci of healthy volunteers and patients with different degrees of OA. METHODS: Patients with mild OA (n = 19; 37-86 years; 10 males) or advanced OA (n = 12; 52-88 years; 4 males) and healthy volunteers (n = 17; 20-49 years; 7 males) were scanned with T2-FSE and UTE-Cones-MT sequences at 3T. Morphological assessment was performed using meniscal whole-organ magnetic resonance imaging score (WORMS). MMF and MTR were calculated for menisci, and correlated with age and meniscal WORMS scores. The diagnostic efficiency was performed by using receiver operating characteristic (ROC) curve and the area under the curve (AUC) analyses. RESULTS: Decreased MMF and MTR were observed in menisci of patients with mild or advanced OA compared with healthy subjects, and in menisci with tears (Grade 2-4) compared with normal menisci (Grade 0). Significant negative correlations were observed between MMF (r = -0.769, P < 0.01), MTR (r = -0.320, P < 0.01), and meniscal WORMS score. There was a mild negative correlation between MMF (r = -0.438, P < 0.01), MTR (r = -0.289, P < 0.01), and age. The AUC values of MMF and MTR in the four horns of meniscus and the posterior horn medial meniscus for differentiating OA patients from healthy volunteers were 0.762 and 0.699, and 0.835 and 0.883, respectively. CONCLUSION: The 3D UTE-Cones-MT biomarkers of MTR and especially MMF can detect compositional changes in meniscus and differentiate healthy subjects from patients with mild or advanced knee OA.

Inversion Recovery Ultrashort TE MR Imaging of Myelin is Significantly Correlated with Disability in Patients with Multiple Sclerosis.

BACKGROUND AND PURPOSE: MR imaging has been widely used for the noninvasive evaluation of MS. Although clinical MR imaging sequences are highly effective in showing focal macroscopic tissue abnormalities in the brains of patients with MS, they are not specific to myelin and correlate poorly with disability. We investigated direct imaging of myelin using a 2D adiabatic inversion recovery ultrashort TE sequence to determine its value in assessing disability in MS. MATERIALS AND METHODS: The 2D inversion recovery ultrashort TE sequence was evaluated in 14 healthy volunteers and 31 patients with MS. MPRAGE and T2-FLAIR images were acquired for comparison. Advanced Normalization Tools were used to correlate inversion recovery ultrashort TE, MPRAGE, and T2-FLAIR images with disability assessed by the Expanded Disability Status Scale. RESULTS: Weak correlations were observed between normal-appearing white matter volume (R = -0.03, P = .88), lesion load (R = 0.22, P = .24), and age (R = 0.14, P = .44), and disability. The MPRAGE signal in normal-appearing white matter showed a weak correlation with age (R = -0.10, P = .49) and disability (R = -0.19, P = .31). The T2-FLAIR signal in normal-appearing white matter showed a weak correlation with age (R = 0.01, P = .93) and disability (R = 0.13, P = .49). The inversion recovery ultrashort TE signal was significantly negatively correlated with age (R = -0.38, P = .009) and disability (R = -0.44; P = .01). CONCLUSIONS: Direct imaging of myelin correlates with disability in patients with MS better than indirect imaging of long-T2 water in WM using conventional clinical sequences.

[Research progress of the application of regional citrate anticoagulation in artificial liver to treat liver failure].

Liver failure is a rapidly progressive condition with a high mortality rate. Artificial liver treatment is one of the most important treatments for liver failure. In order to ensure the smooth functioning of in vitro circulation device, anticoagulants such as heparin or low-molecular-weight heparin are often used in clinical practice. However, it induces hemorrhage, thrombocytopenia and other adverse reactions, thereby threatening the life safety of liver failure patients. Regional citrate anticoagulation does not affect the coagulation mechanism in vivo, nor does it effects platelets, so in vitro circulating anticoagulants has become the first choice anticoagulant treatment method for continuous renal replacement therapy. Combined with the current research condition at home and abroad, the research progress of the application of regional citrate anticoagulation in artificial liver to treat liver failure is discussed, covering its principle content, application status and application prospect.

[Clinical application effect of blood circulation enhancement technique in repairing large area of skin and soft tissue defects of extremities with super large free anterolateral thigh flap].

Objective: To observe the clinical application effect of blood circulation enhancement technique in repairing large area of skin and soft tissue defects of extremities with super large free anterolateral thigh flap. Methods: From March 2014 to March 2017, 6 patients with large area of skin and soft tissue defects of extremities were hospitalized in our unit, including 5 males and 1 female, aged 27-65 years, 1 case of electric injury, 2 cases of coal burn, 3 cases of traffic injury, 2 cases involving upper limb, and 4 cases involving lower limb. After debridement, the wound area ranged from 26 cm×8 cm to 36 cm×15 cm, and the bone exposure area ranged from 24 cm×7 cm to 35 cm×14 cm. The blood circulation enhancement technique was used when the wound with bone exposure was repaired with super large free anterolateral thigh flap. The area of flaps ranged from 28 cm×10 cm to 38 cm×16 cm. The donor site of flap and the primary wound without bone exposure were repaired with medial thigh split-thickness skin graft of the donor leg of flap. The blood circulation enhancement technique mode during operation and the survival of flaps after operation were recorded, and the recovery of donor and recipient areas and the occurrence of complications were followed up. Results: Three patients were treated with simple vascular supercharging technique during flap transplantation, and the other 3 patients were treated with vascular supercharging and turbocharging technique during flap transplantation. All the flaps survived well in 6 patients without vascular crisis. Follow-up for 3 to 12 months after surgery showed that the blood flow of the flaps was good and the depth and superficial sensation recovered to varying degrees. Except for 1 case of upper limb flap, the other flaps had no obvious swelling and needed no second thinning. There were only depressed scars in the donor sites, and no obvious scar hyperplasia in the area without bone exposure repaired by the skin grafts. No short-term or long-term complications were found. Conclusions: The application of blood circulation enhancement technique in repairing large area of skin and soft tissue defects of extremities with super large free anterolateral thigh flaps provides reliable blood supply for the flaps and results in good effect after operation, which is worth popularizing.

Ultrastrong and Stiff Carbon Nanotube/Aluminum-Copper Nanocomposite via Enhancing Friction between Carbon Nanotubes.

Researchers have been aiming to replace copper with carbon nanotube/copper nanocomposites, which are lighter and exhibit better electrical, mechanical, and thermal properties. However, the strength is far below pure carbon nanotube assembly and even much lower than some copper-based alloys. This disadvantage hinders the extensive application of carbon nanotube/copper nanocomposites. In this study, the carbon nanotube/aluminum-copper nanocomposites with ultra-strength and stiffness were prepared. The strength and elasticity modulus of composite reached as high as 6.6 and 500 GPa, respectively, while a high conductivity of 1.8 × 107 S/m was maintained. This can be attributed to the diffusion of Cu and Al atoms into the carbon nanotube fiber, which enhances friction between the carbon nanotubes by "pinning" and "bridging". This structure provides us with novel insights into the design of carbon nanotubes/metal nanocomposites with ultrahigh strength and conductivity.

[Relationship of TLR2 and TLR4 expressions on the surface of peripheral blood mononuclear cells to small intestinal bacteria overgrowth in patients with hepatocellular carcinoma].

Objective: To investigate TLR2 and TLR4 expressional situation on the surface of peripheral blood mononuclear cells (PBMC) in patients with hepatocellular carcinoma (HCC) and their relationship with small intestinal bacterial overgrowth (SIBO). Methods: Flow cytometry was used to detect TLR2 and TLR4 expressional situation on the surface of PBMC in 78 cases with HCC, 56 cases with cirrhosis and 33 healthy controls. Furthermore, lactose hydrogen breath test (LHBT) was used to detect small intestinal bacterial overgrowth. Results: Of the 78 cases with HCC, 56 cases (71.8%) were SIBO-positive, 23 cases (41.1%) were SIBO- positive in 56 cases with cirrhosis, and 1 (3.0%) was SIBO-positive in 33 healthy controls. The incidence of SIBO in HCC patients was higher than cirrhosis patients (χ(2) = 12.72, P < 0.05) and healthy controls (χ(2) = 41.18, P < 0.05). The expression levels of TLR2 and TLR4 in HCC patients (100.55 ± 24.22, 42.76 ± 15.96) were significantly higher than cirrhosis (67.42 ± 18.36, 24.38 ± 8.68)and healthy control group (33.06 ± 11.72, 12.52 ± 4.46) (P < 0.05). Furthermore, the expression levels of TLR2 and TLR4 in SIBO-positive patients (108.75 ± 20.40, 48.1 ± 14.98) were higher than SIBO-negative patients (79.67 ± 20.60, 28.62 ± 7.36) (P < 0.05). Conclusion: The expression of TLR2 and TLR4 and the incidence of SIBO in HCC patients are significantly higher than cirrhosis and healthy control group. Moreover, the high expressions of TLR2 and TLR4 in SIBO-positive HCC patients may promote the development of HCC.

[Cogan syndrome with audiovestibular disfunction: 2 cases report].

We describe a case of Cogan syndrome in patients with clinical manifestations, related examinations and diagnosis,treatment,and review of relevant literature. Both patients had bilateral moderate to severe sensorineural hearing loss. The collateral function test showed that there were bilateral semicircular canal paresis,and the head impulse test had a bilateral gain value between 0.09 and 0.55. It showed obvious compensatory saccade wave, the head impulse suppression test bilateral no anti-compensation saccade wave.Cogan syndrome is a rare syndrome with unspecific symptoms and early diagnosis is difficult. However, the involvement of the auditory vestibular systems are often poor prognosis and needs to be diagnosed by early diagnosis and treatment.

[miRNA-96-5p inhibits the proliferation and migration of gastric cancer cells by targeting FoxQ1].

Objective: To investigate the role of microRNA-96-5p in the proliferation and invasion of gastric cancer cells and its molecular mechanism. Methods: From June 2015 to January 2017, 53 resected specimens were collected. The transcriptional levels of microRNA-96-5p and forkhead box Q1 (FoxQ1) in gastric cancer tissues and the matched para-cancerous tissues were quantified by quantitative real-time PCR (qRT-PCR). The expression of FoxQ1 protein was also detected by immunohistochemistry (IHC). The relationship between microRNA-96-5p expression and the clinicopathological features of gastric cancer and its correlation with FoxQ1 expression were analyzed. The expressions of miRNA-96-5p in gastric cancer tissue and adjacent normal tissue were detected by qRT-PCR. miRNA-96-5p mimics was transfected to BGC-823 gastric cancer cells. The effects of miRNA-96-5p on cell proliferation and invasion were detected by cell counting kit-8 (CCK-8) assay and Transwell assay, respectively. The protein expressions of FoxQ1, E-cadherin and vimentin were determined by western blot. The relationship between FoxQ1 and miRNA-96-5p expressed in BGC-823 cells was detected by dual-luciferase reporter assay. Results: The median expression of miRNA-96-5p in gastric cancer tissue was 1.05, significantly lower than 3.23 of para-cancerous tissues (P<0.05). The positive rate of FoxQ1 expression in gastric cancer tissue was 71.7%, significantly higher than 28.3% of para-cancerous tissues (P<0.05). The expression of FoxQ1 was negatively corelated with the level of miRNA-96-5p (r=-0.613, P=0.006). The expression of miRNA-96-5p in gastric cancer cell BGC-823 was significantly decreased compared with normal gastric epithelial cell (0.96±0.08 vs 2.84±0.15, P<0.05). The results of CCK-8 assay and Transwell assay showed that overexpression of miRNA-96-5p significantly reduced the proliferation and invasion abilities of gastric cancer cells (P<0.05). Overexpression of miRNA-96-5p decreased the protein level of FoxQ1. Moreover, it upregulated the expression of E-cadherin and downregulated the expression of vimentin. The result of dual-luciferase-3'-UTR reporter assay confirmed that miRNA-96-5p binds to the 3'UTR of FoxQ1. Conclusion: miRNA-96-5p may suppress the proliferation, migration and epithelial-mesenchymal transition (EMT) of gastric cancer cell by down-regulation of FoxQ1.

[Clinical effects of perforating branch flaps of medial vastus muscle in repairing secondary wounds in donor sites of free anterolateral femoral perforator flaps].

Objective: To investigate the clinical effects of perforating branch flaps of medial vastus muscle in repairing secondary wounds in donor sites of free anterolateral femoral perforator flaps. Methods: From August 2014 to December 2016, 12 patients (8 males and 4 females, aged 35-72 years) with skin and soft tissue defects of extremities associated with tendon and bone exposure were treated in Hanzhong Central Hospital. The sizes of the primary wounds after debridement were 10 cm×8 cm-22 cm×14 cm, and the wounds were repaired with 12 cm×10 cm-24 cm×16 cm free anterolateral femoral perforator flaps. The anterolateral femoral donor sites, which were 8.0 cm×4.0 cm-14.0 cm×7.5 cm in the secondary wounds after skin extensional suture, were repaired with perforating branch flaps of medial vastus muscle in the size of 9.0 cm×5.0 cm-15.0 cm×8.5 cm. The medial femoral donor sites were sutured directly. Results: All the perforating branch flaps of medial vastus muscle and free anterolateral femoral perforator flaps survived in 12 patients. Following up for 6 to 12 months, the medial femoral perforator flaps had good local shape and texture. The flaps of 8 patients without cutaneous nerve transection were sensitive. The sensation of the flaps of the other 4 patients gradually recovered, and the functions of the ipsilateral knee joints were normal. Conclusions: The medial femoral perforator flap has a stable anatomy and abundant blood supply, which can be used to repair the secondary wound in the donor site of the free anterolateral femoral perforator flap conveniently. It is safe and easy to be popularized. Moreover, it has a good shape and function after operation.

Apoptosis of hepatocarcinoma cells Hepg2 induced by Huaier extract through regulation of HBx and CEACAM1 gene expression..

Huaier can effectively inhibit the growth of tumor cells by enhancing the immune system. However, the mechanism of its function is still not clear. The current study aimed to explore the possible mechanism of Huaier in inhibiting human hepatocarcinoma cells by observing its effect on proliferation and invasion in hepatocarcinoma cells, HepG2 and HepG2-X, which stably express the HBx gene, and by comparing the levels of mRNA transcription and protein expression of HBx and CEACAM1 in HepG2 cells and HepG2-X cells when treated with different concentrations of Huaier. HepG2 cells and HepG2-X cells were treated with 0, 1.5, 3.0, and 6.0 g/L-1 Huaier extract in vitro. MTT assay was used to measure the inhibition of cell proliferation. The transwell cell model coated with Matrigel glue was used to detect the invasion of HepG2 and HepG2-X cells in vitro. Flowcytometry was used to observe changes in cell cycle. Real-time PCR and Western blot were used to detect HBx and CEREAM1 mRNA transcription and protein expression separately. Huaier extract can inhibit HepG2 and HepG2-X cell proliferation in a time- and dose-dependent manner. The A value of HepG2-X cells in each group was higher than that of HepG2 cells. Compared with the control group, the invasion ability of HepG2 and HepG2-X cells decreased significantly after treatment with Huaier extract, in a dose-dependent manner. The cell cycle of HepG2 and HepG2-X was arrested at S phase. The distribution of G0/G1 phase decreased gradually with the increase of the concentration of Huaier extract, and the proportion of G0/G1 phase distribution declined. After treating with Huaier extract, mRNA transcription and protein expression of HBx in HepG2 and HepG2-X declined, while those of CEACAM1 increased, reflecting a dose-dependent manner (P less than 0.05). Therefore, we concluded that the inhibitory effect of Huaier extract on hepatocarcinoma cell proliferation might function through down regulation of HBx gene expression and upregulation of CEACAM1 gene expression.

Determination of atomic-scale chemical composition at semiconductor heteroepitaxial interfaces by high-resolution transmission electron microscopy.

The determination of atomic structures and further quantitative information such as chemical compositions at atomic scale for semiconductor defects or heteroepitaxial interfaces can provide direct evidence to understand their formation, modification, and/or effects on the properties of semiconductor films. The commonly used method, high-resolution transmission electron microscopy (HRTEM), suffers from difficulty in acquiring images that correctly show the crystal structure at atomic resolution, because of the limitation in microscope resolution or deviation from the Scherzer-defocus conditions. In this study, an image processing method, image deconvolution, was used to achieve atomic-resolution (∼1.0 Å) structure images of small lattice-mismatch (∼1.0%) AlN/6H-SiC (0001) and large lattice-mismatch (∼8.5%) AlSb/GaAs (001) heteroepitaxial interfaces using simulated HRTEM images of a conventional 300-kV field-emission-gun transmission electron microscope under non-Scherzer-defocus conditions. Then, atomic-scale chemical compositions at the interface were determined for the atomic intermixing and Lomer dislocation with an atomic step by analyzing the deconvoluted image contrast. Furthermore, the effect of dynamical scattering on contrast analysis was also evaluated for differently weighted atomic columns in the compositions.

InP-based pseudomorphic InAs/InGaAs triangular quantum well lasers with bismuth surfactant.

An InP-based 2.1 µm InAs/In0.53Ga0.47As triangular quantum well laser grown with Bi surfactant has shown improved performance in comparison to the device with the same structure but grown without Bi surfactant. Under continuous-wave driving operation, the output light power is increased from 32.6 to 37.5 mW at the same injecting current of 850 mA at 200 K. The external differential and internal quantum efficiencies for the laser with Bi surfactant are 18.4% and 41%, respectively, which are correspondingly higher than 13.1% and 31% for the reference device. Furthermore, a decreased internal loss from 20.9 to 17.6 cm-1 for the Bi surfactant laser is also observed. These results suggest that Bi surfactant is promising for further enhancing performances of strained quantum well laser diodes.

[Research advances in chronicity of hepatitis E virus infection].

Hepatitis E virus (HEV) infection usually causes acute hepatitis and has a self-limiting progression. The patients often recover within 6 months with good prognosis. Recent studies have found that HEV infection may become chronic in special situations, which manifests as persistent liver function abnormalities for at least 6 months after acute HEV infection and the presence of viral nucleic acid in serum, feces, and/or liver tissue. Chronicity of HEV infection mainly occurs in immunocompromised patients, and it is rare but very dangerous in clinical practice. An understanding of the pathogenesis, clinical manifestations, treatment methods, and preventive measures of chronicity of HEV infection helps clinical physicians develop an effective management regimen and improve patient prognosis. This article introduces related issues, in order to raise the awareness of this disease among clinical physicians.