[Research progress on the role of adipose-derived stem cell exosomes in skin scar formation].

The adipose-derived stem cell exosomes are subcellular structures of adipose stem cells. They are nano-sized membrane vesicles that can transport various cell components and act on target cells by paracrine, and they play an important role in the exchanges of substance and information between cells. Scar healing is the commonest way of healing after skin tissue injury. Pathological scar can not only cause movement dysfunction, but also lead to deformity, which affects the appearance of patients and brings life and mental pressure to the patients. In recent years, many researches have shown that the adipose-derived stem cell exosomes contain a variety of bioactive molecules, which play an important role in reducing scar formation and scar-free wound healing, by affecting the proliferation and migration of fibroblasts and the composition of extracellular matrix. This article reviewed the recent literature on the roles and mechanisms of adipose-derived stem cell exosomes in scar formation, and prospected the future application and development of adipose-derived stem cell exosomes in scar treatment.

Modulation of narrow-field amacrine cells on light-evoked spike responses and receptive fields of retinal ganglion cells.

By using multi-electrode array (MEA) recording technique in conjunction with white-noise checkerboard stimuli and reverse correlation methods, we studied modulatory actions of glycinergic narrow-field amacrine cells (NFACs) on spatiotemporal profiles of five functional groups of ganglion cells (GCs) in dark-adapted mouse retinas. We found that application of 2 µM strychnine significantly altered light-evoked spike rates of three groups of GCs. It also decreased receptive field center radii of all five groups of GC by a mean value of 11%, and shifted the GC receptive field (RF) centers of all GCs and the mean shift distances for the sustained GCs are significantly longer than the transient GCs. On the other hand, strychnine did not affect temporal profiles of the GC center responses, as it did not alter the time-to-peak or the biphasic index of the spike triggered average (STA) functions of GC RF centers. Strychnine also exerts limited actions on RF surrounds of most GCs, except that it moderately weakens the antagonistic surround of sustained OFF GCs and strengthens the antagonistic surround of the ON/OFF GCs, possibly through serial connections between NFACs and GABAergic wide-field amacrine cells (WFACs). Using the Sum of Separable Subfilter (SoSS) model and singular value decomposition method, we decomposed GCs' STAs into five space-time separable subfilters, studied the observation rates of each subfilter in the five functional groups of GCs and determined NFAC-dependent and -independent synaptic circuitries that mediate center and surround responses of various groups of mouse retina retinal ganglion cells.

[Effects of comprehensive treatment of infected wounds in patients with iatrogenic Cushing's syndrome].

Objective: To investigate the characteristics and comprehensive treatment of infected wounds in patients with iatrogenic Cushing's syndrome. Methods: A retrospective observational study was conducted. From May 2012 to December 2021, the data of 19 patients with iatrogenic Cushing's syndrome discharged from the Department of Burns and Plastic Surgery of the First Affiliated Hospital of Guangxi Medical University were collected, including 8 males and 11 females, aged 28-71 (56±11) years, with 12 cases of infected acute wounds and 7 cases of infected chronic wounds. The lesions were located in the limbs, perianal, and sacrococcygeal regions, with original infection ranging from 9 cm×5 cm to 85 cm×45 cm. After admission, the patients were performed with multidisciplinary assisted diagnosis and treatment, and the wounds were treated with debridement and vacuum sealing drainage, according to the size, severity of infection, suture tension, and bone and tendon tissue exposure of wounds, direct suture or autologous skin and/or artificial dermis and/or autologous tissue flap transplantation was selected for wound repair. The levels of cortisol and adrenocorticotropic hormone (ACTH) of patients at 8:00, 16:00, and 24:00 within 24 h after admission were counted. After admission, the number of operations, wound repair methods, and wound and skin/flap donor site healing of patients were recorded. During follow-up, the wounds were observed for recurrent infection. Results: The cortisol levels of 16 patients at 8:00, 16:00, and 24:00 within 24 h after admission were (130±54), (80±16), and (109±39) nmol/L, respectively, and ACTH levels were (7.2±2.8), (4.1±1.8), and (6.0±3.0) pg/mL, respectively; and the other 3 patients had no such statistical results. After admission, the number of surgical operation for patients was 3.4±0.9. The following methods were used for wound repair, including direct suturing in 4 cases and autologous skin and/or artificial dermis grafting in 9 cases, of which 2 cases underwent stage Ⅱ autologous skin grafting after artificial dermis grafting in stage Ⅰ, and 6 cases had pedicled retrograde island flap+autologous skin grafting. The wound healing was observed, showing that all directly sutured wounds healed well; the wounds in 6 cases of autologous skin and/or artificial dermis grafting healed well, and the wounds in 3 cases also healed well after the secondary skin grafting; the flaps in 4 cases survived well with the wounds in 2 cases with distal perforators flap arteries circumfluence obstacle of posterior leg healed after stage Ⅱ debridement and autologous skin grafting. The healing status of skin/flap donor sites was followed showing that the donor sites of medium-thickness skin grafts in the thigh of 4 cases were well healed after transplanted with autologous split-thickness grafts from scalp; the donor sites of medium-thickness skin grafts in 3 cases did not undergo split-thickness skin grafting, of which 2 cases had poor healing but healed well after secondary skin grafting 2 weeks after surgery; the donor sites of split-thickness skin grafts in the head of 2 patients healed well; and all donor sites of flaps healed well after autologous skin grafting. During follow-up of more than half a year, 3 gout patients were hospitalized again for surgical treatment due to gout stone rupture, 4 patients were hospitalized again for surgical treatment due to infection, and no recurrent infection was found in the rest of patients. Conclusions: The infected wounds in patients with iatrogenic Cushing's syndrome have poor ability to regenerate and are prone to repeated infection. Local wound treatment together with multidisciplinary comprehensive treatment should be performed to control infection and close wounds in a timely manner, so as to maximize the benefits of patients.

Glycinergic and GABAergic interneurons shift the location and differentially alter the size of ganglion cell receptive field centers in the mammalian retina.

By using the multi-electrode array (MEA) recording technique in conjunction with white-noise checkerboard stimuli and reverse correlation methods, we studied modulatory actions of glycinergic and GABAergic interneurons on spatiotemporal profiles of ganglion cells (GCs) in dark-adapted mouse retinas. We found that application of 2 µM strychnine decreased receptive field center radii of GCs by a mean value of 11%, and shifted the GC receptive field (RF) centers by a mean distance of 28.3 µm. On the other hand, 200 µM picrotoxin + 100 µM bicuculline + 50 µM TPMPA increased GC receptive field center radii by a mean value of 19%, and shifted the GC RF centers by a mean distance of 53.7 µm. Glycinergic neurons in the mouse retina are narrow-field amacrine cells that have been shown to mediate ON-OFF crossover inhibitory synapses within the RGs' RF center, therefore they may increase the size and shift the location of GC RF center by synergistic addition to bipolar cell inputs to GCs. GABAergic neurons are wide-field amacrine cells and horizontal cells that are known to mediate antagonistic surround responses of GCs, and thus they decrease the GCs' RF center size. Our results suggest that a major global function of glycinergic and GABAergic interneurons in the mammalian retina is to provide the flexibility for adjusting the size and location of GCs' RF centers. The apparent shifts of GC RF centers suggest that the synergistic addition by GlyACs and the surround inhibition by GABAergic interneurons are not spatially symmetrical within GC RFs.

Evaluation of the Biofire FilmArray meningitis/encephalitis assay for the detection of Cryptococcus neoformans/gattii.

OBJECTIVES: Cryptococcal meningitis (CM) remains an important cause of morbidity and mortality among immunocompromised patients. Laboratory diagnostics for CM includes antigen detection, staining and culture. Data on the performance of the Biofire® FilmArray® meningitis/encephalitis (ME) panel for detecting Cryptococcus neoformans/gattii is limited, with several reports describing false negativity for this target. METHODS: A retrospective analysis of 1384 physician-ordered ME panel tests ordered between January 2017 to October 2018 was performed. ME panel results were compared to cerebrospinal fluid (CSF) cryptococcal antigen (CrAg) and CSF culture testing and clinical significance of cryptococcal detection was determined. RESULTS: There were 34 patients positive for cryptococcal detection by either ME panel, CSF CrAg or CSF culture in 2.7% of CSF specimens tested (38/1384). Of the 34 patients positive for cryptococcal detection, 85.3% were human immunodeficiency virus positive (29/34). The ME panel detected 32/38 (84.2%) cryptococcal-positive specimens, culture detected 28/38 (73.7%) and CSF CrAg was positive in 37/38 specimens (97.4%). The ME panel had a sensitivity and specificity of 96.4% (95% CI 81.7-99.9%) and 99.6% (95% CI 99.2-99.9%) compared with culture, and 83.8% (95% CI 68.0-93.8%) and 99.9% (95% CI 99.6-100.0%) compared to CSF CrAg testing, respectively. CrAg titres were lower among ME panel-negative, culture-negative specimens compared with ME panel-positive, culture-negative specimens (reciprocal median end-point titres of 128 ± 60 vs. 1920 ± 1730, p 0.04). All five CrAg-positive, ME panel- and culture-negative specimens were obtained from previously treated CM patients. DISCUSSION: The ME panel had high correlation with CSF culture and a somewhat lower correlation with CSF CrAg testing. The potential utility of using negative ME panel test results to predict culture sterility among patients undergoing treatment for CM warrants further study.

Genetic dissection of rod and cone pathways mediating light responses and receptive fields of ganglion cells in the mouse retina.

Retinal ganglion cells (GCs) are important visual neurons which carry complex spatiotemporal information from the retina to higher visual centers in the brain. By taking advantage of pathway-specific knockout/mutant mice and multi-electrode array (MEA) recording techniques, we analyze contributions of rod and cone pathways to responsiveness, kinetics and receptive field profiles of GCs under scotopic and photopic conditions. Our data suggest: (1) Scotopic responses of some GCs require all three rod pathways, some require only the secondary and tertiary rod pathways, and others require only the tertiary rod pathway. (2) There are more responsive GCs in photopic conditions than responsive GCs in scotopic conditions. (3) Gap junctions slow down GCs' scotopic light responses and increase GCs' ratio of antagonistic to center inputs. (4) Cone pathways do not affect the kinetics but alter the ratio of antagonistic to center inputs of scotopic GC responses, and they speed up GCs photopic responses and alter the ratio of GCs' antagonistic to center synaptic inputs and receptive field profiles. (5) Rod bipolar cells shorten response latency of ON GCs and increase the ratio of GCs' antagonistic to center synaptic inputs. (6) Light adaptation speeds up GCs' temporal processing and tunes GC photopic responses to higher frequencies, and the tertiary rod pathway plays a significant role in adaptation-induced TTP changes in some GCs. (7) GC RF center sizes are partially mediated by AIIACs and GC-GC coupling. (8) Connexin36 gap junctions and cone pathways alter synaptic circuits underlying antagonistic surround inputs to GCs in photopic conditions.

[A phase II, single-arm, open-label, multicenter clinical study to evaluate the efficacy and safety of sofosbuvir combined with ribavirin in patients with genotype 2 chronic hepatitis C virus infection].

Objective: To evaluate the efficacy and safety of sofosbuvir (Nanjing Zhengda Tianqing Pharmaceutical Co., Ltd.) combined with ribavirin in patients with genotype 2 chronic hepatitis C virus infection. Methods: Treatment-naïve or treatment experienced genotype 2 chronic hepatitis C patients from sixteen research centers of China were screened. All subjects received once-daily dose of sofosbuvir (400 mg) combined with ribavirin (body weight < 75 kg, 1 000 mg/day, 400 mg in the morning and 600 mg in the evening; body weight > 75 kg, 1 200 mg/d, 600 mg in the morning and 600 mg in the evening) for 12 weeks. Patients were followed-up for a period of 12 weeks after discontinuation of treatment. Continuous variables were expressed as mean ± standard deviation. The proportion of subjects with virologic response at different follow-up time points and 95% confidence intervals were estimated by maximum likelihood ratio and Clopper-Pearson interval. Results: 132 cases with genotype 2 chronic hepatitis C virus infection from sixteen research centers of China were included, 12 cases of whom were associated with cirrhosis, and the remaining 120 cases were not associated with cirrhosis. One hundred and thirty-one cases completed the study, and one patient lost to follow-up at week 4 after the end of treatment. The sustained virological response rate was 96.2% (95% confidence interval: 92.37% - 99.16%) after 12 weeks of drug withdrawal. Virological relapse occurred in four cases. Of the 132 subjects enrolled in the study, 119 (90.2%) reported 617 adverse events during treatment, of which 359 (76.5%) were TEAE related to sofosbuvir and/or ribavirin. There were nine TEAEs of grade 3 and above, and six cases (4.5%) of them had six severe adverse events. Only one serious adverse event was associated with sofosbuvir and ribavirin (unstable angina pectoris). There were no adverse events leading to drug discontinuation or death. Conclusion: Sofosbuvir combined with ribavirin has a high SVR rate in the treatment of genotype 2 chronic hepatitis C virus infection, and most of the adverse events occurred were mild with acceptable safety profile.

Defective Central Immune Tolerance Induced by High-Dose D-Galactose Resembles Aging.

D-Galactose (D-Gal) promotes accumulation of reactive oxygen species and formation of advanced glycation end-products, ultimately resulting in oxidative stress. D-Gal has been widely used to induce accelerated aging in anti-aging medical research. Although thymic epithelial cells are particularly sensitive to oxidative stress, there are few reports on the thymus changes accompanying D-Gal-induced aging in mice. To study the effect of D-Gal on rodent thymus, we investigated the degree of thymus atrophy and changes in the atrophy relative index in C57BL/6J mice following subcutaneous injection of D-Gal at different doses (200, 500, 1000 mg/kg per day) for 60 days. Compared with the vehicle-treated (0.9% saline) and young controls, D-Gal at doses of 500 and 1000 mg/kg per day led to a significant thymic atrophy; the latter dose caused atrophy similar to that observed in naturally aged (18-20-month-old) mice. Mice treated with high-dose D-Gal exhibited greater immunosenescence, defective central immune tolerance, increased levels of activated splenic immune cell, and chronic low-grade inflammation, i.e., outcomes similar to those observed in natural aging in mice. Taken together, our results indicate that mice treated with high-dose D-Gal may be a valid model for studying induced thymic atrophy and effects of aging on the immune system.

Emergence of dalbavancin non-susceptible, vancomycin-intermediate Staphylococcus aureus (VISA) after treatment of MRSA central line-associated bloodstream infection with a dalbavancin- and vancomycin-containing regimen.

OBJECTIVES: Dalbavancin is a long-acting lipoglycopeptide with activity against gram-positives, including methicillin-resistant Staphylococcus aureus (MRSA). The potential for lipoglycopeptides, with half-lives greater than 1 week, to select for resistance is unknown. Here we explore a case of MRSA central line-associated bloodstream infection in which dalbavancin and vancomycin non-susceptibility emerged in a urine isolate collected after the patient was treated with vancomycin and dalbavancin sequentially. METHODS: Isolates from blood and urine underwent susceptibility testing, and whole genome sequencing (WGS). The blood isolate was subjected to successive passage in vitro in the presence of escalating dalbavancin concentrations and the emergent isolate was subjected to repeat susceptibility testing and WGS. RESULTS: The blood isolate was fully susceptible to vancomycin; however, MICs of the urine isolate to dalbavancin, vancomycin, telavancin, and daptomycin were at least fourfold higher than the blood-derived strain. Both strains were indistinguishable by spa and variable number tandem repeat (VNTR) typing, and WGS revealed only seven variants, indicating clonality. Four variants affected genes, including a 3bp in-frame deletion in yvqF, a gene which has been implicated in glycopeptide resistance. Vancomycin and dalbavancin non-susceptibility emerged in the blood isolate after successive passage in vitro in the presence of dalbavancin, and WGS identified a single non-synonymous variant in yvqF. CONCLUSIONS: This is the first case in which VISA has emerged in the context of a dalbavancin-containing regimen. The selection for cross-resistance to vancomycin in vitro by dalbavancin exposure alone is troubling. Clinicians should be aware of the possibility for emergence of dalbavancin non-susceptibility and glycopeptide cross-resistance arising following therapy.

[Clinical effect and safety of 144-week treatment with entecavir capsules in treatment-naïve HBeAg-positive patients with chronic hepatitis B].

Objective: To investigate the clinical effect and safety of entecavir capsules in the treatment of treatment-naïve HBeAg-positive patients with chronic hepatitis B (CHB). Methods: A total of 158 HBeAg-positive CHB patients were given oral entecavir capsules at a dose of 0.5 mg/time once a day for 144 weeks. Clinical outcome and safety were evaluated at baseline and at 24, 48, 72, 96, 120, and 144 weeks of treatment respectively. The Fisher's exact test was used for the analysis of categorical data. Results: After 144 weeks of treatment, 90.91% of all patients achieved virologic response (< 69 IU/ml), the normalization rate of alanine aminotransferase was 88.18%, the clearance rate of HBeAg was 33.33%, and the seroconversion rate of HBeAg was 24.07%. Of all patients, 2 dropped out due to adverse events and 5 experienced serious adverse reactions. Conclusion: Entecavir capsules can inhibit viral replication and have good safety in treatment-naïve HBeAg-positive CHB patients.

Elevated IOP alters the space-time profiles in the center and surround of both ON and OFF RGCs in mouse.

Glaucoma is a leading cause of blindness worldwide, and is characterized by progressive retinal ganglion cell (RGC) death. An experimental model of glaucoma has been established by elevating the intraocular pressure (IOP) via microbead occlusion of ocular fluid outflow in mice. Studies in this model have found visual dysfunction that varied with adaptational state, occurred before anatomical changes, and affected OFF RGCs more than ON RGCs. These results indicate subtle alterations in the underlying retinal circuitry that could help identify disease before irreversible RGC changes. Therefore, we looked at how RGC function was altered with elevated IOP under both photopic and scotopic conditions. We first found that responses to light offset are diminished with IOP elevation along with a concomitant decrease in receptive field center size for OFF RGCs. In addition, the antagonistic surround strength and size was reduced in ON RGCs. Furthermore, elevation of IOP significantly accelerated the photopic temporal tuning of RGC center responses in both ON and OFF RGCs. We found that some of the IOP-induced functional changes to OFF RGCs relied on ON cross-over pathways, indicating dysfunction in inner retinal circuitry. Overall, these results suggest that IOP alters multiple functions in the retina depending on the adaptational state. They provide a basis for designing multiple functional tests for early detection of glaucoma and for circuit-specific therapeutic targets in treatment of this blinding disease.

[The multicenter study on the registration and follow-up of low anticoagulation therapy for the heart valve operation in China].

OBJECTIVE: To investigate the optimal anticoagulation methods and monitoring strategy for Chinese patients undergoing heart valve replacement, which is potentially quite different from western populations. METHODS: In this multicenter prospective cohort study, the anticoagulation and monitoring strategy data was acquired from 25 773 in-hospital patients in 35 medical centers and 20 519 patients in outpatient clinic in 11 medical centers from January 1st, 2011 to December 31th, 2015. RESULTS: As for in-hospital patients, mean age of study population was (48.6±11.2) years old; main etiology of valve pathology was rheumatic (87.5%) origin among study cohort; 94.8% of study population received mechanical valve implantation; international normalized ratio (INR) monitoring (in all the study centers) and low-intensity anticoagulation strategy (31 hospitals chose target INR range of 1.5-2.5, and actual values of INR among 89.2% of 100 069 in-hospital monitoring samples were 1.5-2.5), with mean actual INR values of 1.84±0.53, and warfarin dosage of (2.82±0.93) mg/d were widely adopted among the study centers; strategies of in-hospital warfarin administration were similar in all the study centers; complication rates of low-intensity anticoagulation strategy were low in severe hemorrhage (0.02%), thrombosis (0.05%), and thromboembolism (0.05%) events, without anticoagulation-related death.As for 18 974 outpatient clinic patients, the follow-up rate was 92.47%, with a total of 30 012 patient-years (Pty). Anticoagulation-related morbidity and mortality rates were 0.67% and 0.15% Pty; major hemorrhage morbidity and mortality rates were 0.25% and 0.13% Pty; thromboembolism morbidity and mortality rates were 0.45% and 0.03% Pty.The mean dosage of warfarin daily dosage was (2.85±1.23) mg/d and INR value was 1.82±0.57.No significant regional difference in the intensity of anticoagulation therapy was noted during the study. CONCLUSIONS: INR can be used as a normalized indicator for intensity of anticoagulation therapy in China.The optimal anticoagulation intensity with INR range from 1.5 to 2.5 is safe and effective for Chinese patients with heart valve replacement, and there is no significant regional difference in the intensity of anticoagulation therapy.

Magnetic effects in sulfur-decorated graphene.

The interaction between two different materials can present novel phenomena that are quite different from the physical properties observed when each material stands alone. Strong electronic correlations, such as magnetism and superconductivity, can be produced as the result of enhanced Coulomb interactions between electrons. Two-dimensional materials are powerful candidates to search for the novel phenomena because of the easiness of arranging them and modifying their properties accordingly. In this work, we report magnetic effects in graphene, a prototypical non-magnetic two-dimensional semi-metal, in the proximity with sulfur, a diamagnetic insulator. In contrast to the well-defined metallic behaviour of clean graphene, an energy gap develops at the Fermi energy for the graphene/sulfur compound with decreasing temperature. This is accompanied by a steep increase of the resistance, a sign change of the slope in the magneto-resistance between high and low fields, and magnetic hysteresis. A possible origin of the observed electronic and magnetic responses is discussed in terms of the onset of low-temperature magnetic ordering. These results provide intriguing insights on the search for novel quantum phases in graphene-based compounds.

Comparing mouse and human pluripotent stem cell derived cardiac cells: Both systems have advantages for pharmacological and toxicological screening.

Pluripotent stem cells offer an unparalleled opportunity to investigate cardiac physiology, pharmacology, toxicology and pathophysiology. In this paper we describe the use of both mouse (Nkx2-5(eGFP/w)) and human (NKX2-5(eGFP/w)) pluripotent stem cell reporter lines, differentiated toward cardiac lineage, for live single cell high acquisition rate calcium imaging. We also assess the potential of NKX2-5(eGFP/w) cardiac lineage cells for use toxicological screening as well as establish their sensitivity to a shift between low and high oxygen environments. Differentiated mouse Nkx2-5(eGFP/w) cells demonstrated a wide range of spontaneous oscillation rates that could be reduced by ryanodine (10µM), thapsigargin (1µM) and ZD7288 (10µM). In contrast human NKX2-5(eGFP/w) cell activity was only reduced by thapsigargin (1µM). Human cell survival was sensitive to the addition of trastuzumab and doxorubicin, while the switch from a low to a high oxygen environment affected oscillation frequency. We suggest that the human NKX2-5(eGFP/w) cells are less suitable for studies of compounds affecting cardiac pacemaker activity than mouse Nkx2-5(eGFP/w) cells, but are very suitable for cardiac toxicity studies.

Tenofovir disoproxil fumarate vs adefovir dipivoxil in Chinese patients with chronic hepatitis B after 48 weeks: a randomized controlled trial.

Tenofovir disoproxil fumarate (TDF) has demonstrated long-term efficacy and a high barrier to resistance in multiple chronic hepatitis B (CHB) populations outside of China. This study aimed to evaluate the efficacy and safety of TDF compared with adefovir dipivoxil (ADV) in Chinese patients with CHB during 48 weeks of treatment (ClinicalTrial.gov number, NCT01300234). A Phase 3, multicentred, randomized, double-blind, controlled trial compared the efficacy and safety of TDF with ADV in Chinese patients with CHB. The primary endpoint was the proportion of patients with HBV DNA <400 copies/mL in each treatment group at Week 48, using an unpooled Z-test for superiority. Secondary endpoints included viral suppression, serologic response, histological improvement, normalization of alanine aminotransferase (ALT) levels and the emergence of resistance mutations. A total of 509 patients, 202 hepatitis B e antigen (HBeAg)-positive and 307 HBeAg-negative, with HBV DNA ≥10(5) copies/mL received either TDF 300 mg od or ADV 10 mg od. At Week 48, TDF demonstrated superior viral suppression compared with ADV in both HBeAg-positive (76.7% vs 18.2%, P < 0.0001) and HBeAg-negative (96.8% vs 71.2%, P < 0.0001) patients. The majority of patients in both treatment arms achieved ALT normalization (>85%). No resistance to TDF was observed. The frequency of adverse events was comparable between treatment arms (TDF 3.9% vs ADV 4.8%). In this double-blind, randomized, clinical trial, TDF demonstrated superiority over ADV with respect to viral suppression in Chinese patients with CHB at 48 weeks of treatment and without the development of resistance.

An international, prospective, multicenter evaluation of the combination of AdvanDx Staphylococcus QuickFISH BC with mecA XpressFISH for detection of methicillin-resistant Staphylococcus aureus isolates from positive blood cultures.

Sepsis caused by Staphylococcus aureus is a major health problem worldwide. Better outcomes are achieved when rapid diagnosis and determination of methicillin susceptibility enable early optimization of antimicrobial therapy. Eight large clinical laboratories, seven from the United States and one from Scotland, evaluated the combination of the Staphylococcus QuickFISH BC and the new mecA XpressFISH assay (both AdvanDx, Woburn, MA, USA) for the detection of methicillin-resistant S. aureus in positive blood cultures. Blood cultures flagged as positive by automated blood culture instruments and demonstrating only Gram-positive cocci in clusters on Gram stain were tested by QuickFISH, a 20-min assay. If only S. aureus was detected, mecA XpressFISH testing followed. The recovered S. aureus isolates were tested by cefoxitin disk diffusion as the reference method. The QuickFISH assay results were concordant with the routine phenotypic testing methods of the testing laboratories in 1,211/1,221 (99.1%) samples and detected 488/491 S. aureus organisms (sensitivity, 99.4%; specificity, 99.6%). Approximately 60% of the samples (730) contained coagulase-negative staphylococci or nonstaphylococci as assessed by the QuickFISH assay and were not tested further. The 458 compliant samples positive exclusively for S. aureus by the QuickFISH assay were tested by the mecA XpressFISH assay, which detected 209 of 211 methicillin-resistant S. aureus organisms (sensitivity, 99.1%; specificity, 99.6%). The mecA XpressFISH assay also showed high reproducibility, with 534/540 tests performed by 6 operators over 5 days achieving reproducible results (98.9% agreement). The combination of the Staphylococcus QuickFISH BC and mecA XpressFISH assays is sensitive, specific, and reproducible for the detection of methicillin-resistant S. aureus and yields complete results in 2 h after the blood culture turns positive.

Thyroid hormone receptor represses miR-17 expression to enhance tumor metastasis in human hepatoma cells.

MicroRNAs (miRNAs) are thought to control tumor metastasis through direct interactions with target genes. Thyroid hormone (T3) and its receptor (TR) are involved in cell growth and cancer progression. However, the issue of whether miRNAs participate in T3/TR-mediated tumor migration is yet to be established. In the current study, we demonstrated that T3/TR negatively regulates mature miR-17 transcript expression, both in vitro and in vivo. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays localized the regions responding to TR-mediated repression to positions -2234/-2000 of the miR-17 promoter sequence. Overexpression of miR-17 markedly inhibited cell migration and invasion in vitro and in vivo, mediated via suppression of matrix metalloproteinases (MMP)-3. Moreover, p-AKT expression was increased in miR-17-knockdown cells that led to enhanced cell invasion, which was blocked by LY294002. Notably, low miR-17 expression was evident in highly metastatic cells. The cell migration ability was increased by T3, but partially reduced upon miR-17 overexpression. Notably, TRα1 was frequently upregulated in hepatocellular carcinoma (HCC) samples and associated with low overall survival (P=0.023). miR-17 expression was significantly negatively associated with TRα1 (P=0.033) and MMP3 (P=0.043) in HCC specimens. Data from our study suggest that T3/TR, miR-17, p-AKT and MMP3 activities are interlinked in the regulation of cancer cell metastasis.

Two years efficiency of lamivudine and adefovir dipivoxil combined therapy in chronic hepatitis B patients.

BACKGROUND: Lamivudine (LAM) and adefovir (ADV) are widely used in most Asian countries, though monotherapy is associated with the occurrence of resistance. AIM: To evaluate the efficiency of LAM and ADV combined treatment of chronic hepatitis B patients with compensated cirrhosis. PATIENTS AND METHODS: 206 eligible Chinese patients were randomly assigned in a 1:1 ratio to receive either LAM or ADV for the first 24 weeks. According to virologic response at 24 weeks, the patients either continued to monotherapy or switched to combined therapy for 48 weeks. After 48 weeks, all patients received LAM and ADV combined therapy for 96 weeks. RESULTS: Serum HBV DNA levels significantly decreased in patients with ADV or LAM monotherapy and continuously reduced after the combined therapy. Serum ALT normalized rate were 88.24% and 81.37% at week 48, and 95.74% and 87.36% at week 96 in ADV and LAM group respectively, comparing to 60.78% and 56.73% in ADV and LAM groups at baseline. The accumulated virological breakthrough rate at week 48 and 96 was significantly higher in LAM group. CONCLUSIONS: Both combination strategies were resulted in the long term virological, biochemical improvement in Chinese chronic hepatitis B patients with compensated cirrhosis.

Full electric control of exchange bias.

We report the creation of a multiferroic field effect device with a BiFeO(3) (BFO) (antiferromagnetic-ferroelectric) gate dielectric and a La(0.7)Sr(0.3)MnO(3) (LSMO) (ferromagnetic) conducting channel that exhibits direct, bipolar electrical control of exchange bias. We show that exchange bias is reversibly switched between two stable states with opposite exchange bias polarities upon ferroelectric poling of the BFO. No field cooling, temperature cycling, or additional applied magnetic or electric field beyond the initial BFO polarization is needed for this bipolar modulation effect. Based on these results and the current understanding of exchange bias, we propose a model to explain the control of exchange bias. In this model the coupled antiferromagnetic-ferroelectric order in BFO along with the modulation of interfacial exchange interactions due to ionic displacement of Fe(3+) in BFO relative to Mn(3+/4+) in LSMO cause bipolar modulation.