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BACKGROUND CONTEXT Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with microscopic tubular technique is an established surgical procedure with several potential advantages, including decreased surgical-related morbidity, reduced length of hospital stay, and accelerated early rehabilitation. A recently introduced biportal endoscopic technique for spine surgery presents familiar surgical anatomy and can be conducted using a conventional approach with a minimal footprint; it is also applicable to TLIF. PURPOSE To compare the clinical and radiological outcomes of biportal endoscopic technique transforaminal lumbar interbody fusion (BE-TLIF) and microscopic tubular technique transforaminal lumbar interbody (MT-TLIF) in patients with single- or two-segment lumbar spinal stenosis with or without spondylolisthesis. STUDY DESIGN A retrospective cohort study. PATIENT SAMPLE One hundred two participants with neurogenic intermittent claudication or lumbar radiculopathy with single- or two-level lumbar spinal stenosis with or without spondylolisthesis. OUTCOME MEASURES Clinical outcomes were assessed using the visual analog scale (VAS) score for the back and leg pain, Oswestry Disability Index (ODI), and the Short Form-36 health survey Questionnaire (SF-36). Demographic data, operative data (total operation time, estimated blood loss, amount of surgical drain, postoperative transfusion, and length of hospital stay), and laboratory results (plasma hemoglobin, serum creatine phosphokinase, and C-reactive protein) were also evaluated. The fusion rate was assessed using the Bridwell interbody fusion grading system. Postoperative complications were also noted. METHODS Patients were divided into two groups: group A (BE-TLIF) and group B (MT-TLIF). The clinical outcomes, including VAS-Back and VAS-Leg, ODI, and SF-36 scores, were evaluated at 1 month, 6 months, and 1 year after surgery. Differences in demographics, operative data, and the laboratory and radiological results were assessed between the two groups. The fusion rate was assessed using standard standing lumbar radiographs and computed tomography scans conducted 1 year after surgery. RESULTS Seventy-nine patients were analyzed in this study, 47 from group A and 32 from group B. Demographic and operative data were comparable for both the groups. The VAS-Back and SF-36 scores were more significantly improved in group A than in group B at 1 month after surgery. However, there were no significant differences between groups for the mean VAS-Back, VAS-Leg, ODI, and SF-36 scores at 1year after the surgery. Although the total operation time was significantly longer in group A, the estimated blood loss and the amount of surgical drainage was significantly higher in group B (p CONCLUSION Both BE-TLIF and MT-TLIF provided equivalent and favorable clinical outcomes and fusion rates. Further large-scale, randomized, controlled trials with long-term follow-ups are warranted.

This study aimed to investigate the therapeutic potential of human umbilical cord mesenchymal stem cells derived exosomes (hUCMSC-Exo) in acute liver failure (ALF) in mice as well as its underlying mechanism. We found that a single tail vein administration of hucMSC-Exo effectively enhanced the survival rate, inhibited apoptosis in hepatocytes, and improved liver function in APAP-induced mouse model of ALF. Furthermore, the deletion of glutathione (GSH) and superoxide dismutase (SOD), generation of malondialdehyde (MDA), and the over production of cytochrome P450 E1 (CYP2E1) and 4-hydroxynonenal (4-HNE) caused by APAP were also inhibited by hucMSC-Exo, indicating that hucMSC-Exo inhibited APAP-induced apoptosis of hepatocytes by reducing oxidative stress. Moreover, hucMSC-Exo significantly down-regulated the levels of inflammatory cytokines IL-6, IL-1β, and TNF-α in APAP-treated livers. Western blot showed that hucMSC-Exo significantly promoted the activation of ERK1/2 and IGF-1R/PI3K/AKT signaling pathways in APAP-injured LO2 cells, resulting in the inhibition of apoptosis of LO2 cells. Importantly, PI3K inhibitor LY294002 and ERK1/2 inhibitor PD98059 could reverse the function of hucMSC-Exo on APAP-injured LO2 cells in some extent. Our results suggest that hucMSC-Exo offer antioxidant hepatoprotection against APAP in vitro and in vivo by inhibitiing oxidative stress-induced apoptosis via upregulation of ERK1/2 and PI3K/AKT signaling pathways.

Aflatoxin is a fungal secondary metabolite with high toxicity that is capable of contaminating various types of food crops. It has been identified as a Group 1 human carcinogen by the International Agency for Research on Cancer. Chronic aflatoxin exposure has caused worldwide concern as a matter of public food safety. Peanuts and peanut products are the major sources of aflatoxin exposure. Therefore, some reduction interventions have been developed to minimize contamination throughout the peanut production chain. The purpose of this study is to estimate the efficacy of interventions in reducing the health impact of hepatocellular carcinoma caused by aflatoxin contamination in peanuts. The estimated total Disability-Adjusted Life Years (DALYs) were calculated using FDA-iRISK software. Six aflatoxin reduction strategies were evaluated, including good agricultural practice (GAP), biocontrol, Purdue Improved Crop Storage packaging, basic processing, ozonolysis, and ultraviolet irradiation. The results indicated that basic processing could prevent huge public health loss of 4,079.7-21,833 total DALYs per year. In addition, GAP and biocontrol were both found to be effective strategies in the farm field. Meanwhile, the other three interventions had limited effectiveness in reducing total DALYs. In conclusion, this study could help farmers, processing plants, and government policy makers to alleviate aflatoxin contamination issues in the peanut production chain.

Ordering properties of a scattering media plays important role in a lasing emission system. In this work, we report a comparison study of optical amplification and lasing action from well aligned and randomly oriented dye doped polymeric nanofibers. Parallel aligned and randomly oriented dye doped polymeric nanofibers were prepared by electrospinning. Different optical phenomenon has been obtained from such two type fiber systems: amplified spontaneous emission from the well aligned nanofibers, and multimode random lasing emission with many sharp peaks from the randomly oriented nanofibers. To evaluate the effect of the microcavity effect, we carry out a comparative study of the optical pumped emission, threshold, and polarization properties of the two systems. Based on the comparison results, we try to discuss the mechanism for the optical cavity formation, where packing arrangement of the fibers plays a key role in the luminescence mechanism. Our comparative study of emission properties from well aligned and randomly oriented fibers manifest that the essence of random lasing is a highly disordered gain medium.

Study Objective To analyze the surgical outcomes and learning curve of transumbilical single-port laparoscopic subtotal hysterectomy, which requires sutures of the cervical stump. Design A prospective observational study (Canadian Task Force classification II-2). Setting A university-affiliated center. Patients From the first (July 2012) and consecutive patients of benign uterine disease scheduled for subtotal hysterectomy until October 2013. Interventions All single-port laparoscopies were performed using straight instruments by 1 gynecologist. An ancillary port was added whenever technical difficulties could endanger surgical quality. Measurement and Main Results Seventy-five patients were recruited for intention-to-treat analysis with a mean (±SD) age of 44.7 ± 3.8 years and a body mass index of 24.2 ± 3.7 kg/m 2 . No major complication was noted. The mean uterine weight was 432.5 ± 344.0 g with 24 (32%) uteri ≧500 g. The patients' sequential order, or gradually increasing experience, was the determining factor in progressively decreasing operative time. Furthermore, most cases that required an additional ancillary port (67%) were clustered in the first 20 cases, whereas 4 were scattered after the 47th patient because of severe pelvic adhesion. The mean operative time decreased in the power law function of the patients' sequential order with a plateau achieved at the 20th patient. Conclusion The patients' sequential order was identified as an independent factor of achieving purely single-port access, and the trend of decreasing operative time delineated the existence of a learning curve. Approximately 20 patients were needed for an experienced multiport laparoscopist to reach technical competency in the current series.

Environmental energy harvesting based on flexible thermoelectric generator (f-TEG) provides an ideal micro-power source to drive the node sensors for the Internet of Things (IoT) and wearable electronics. However, the existing flexible thermoelectric devices have some disadvantages, such as low strength, large thermal resistance, complex manufacturing processes, and low reliability. Here, we report a high-performance f-TEG with a dimension of 2×16×0.6 mm3, encapsulating 18 pairs of thermoelectric legs with the size of 0.38×0.38×0.38 mm3. The flexible polyimide (PI) films with patterned electrodes act as the substrates, of which the upper one is cut into blocks to ensure the generator a minimum bending radius of 4.5 mm. The f-TEG can produce an open circuit voltage of 236 mV and output power of 4.19 mW under a temperature difference of 50 K, which remain almost unchanged even after 7400 times of bending tests. The power density reaches up to 13.1 mW/cm2 at ΔT =50 K, and the normalized output power density is 5.26 μW/cm2·K2. These results are among the best performances reported for f-TEGs, which opens a new avenue for flexible micro-power system design and promotes the development of the next generation self-powered sensors and charge-free electronic devices.

We study gain amplification processes in a single organic microfiber fabricated by melt electro-spinning method. Smooth, individual and cylindrical fiber is obtained. The gain-induced response of the microfiber is found to depend sensitively on the fiber structure. In the homogeneous single fiber where loop cavity forms, high net optical gain of up to 31.4 cm −1 results in spectral narrowing at the material gain peaks. In the case of strong optical feedback, which occurs in such a long microfiber, amplified spontaneous emission with a low threshold of 0.08 mW is obtained. The low threshold and high gain attribute also to the cylindrical cavity which supplies positive feedback.