Effects of different SRT on anaerobic digestion of MSW dosed with various MSWI ashes

This study investigated different solid retention time (SRT) on municipal solid waste (MSW) anaerobic digestion with various MSW incinerator fly ash (FA) and bottom ash (BA) addition. Results showed that biogas production rates (BPRs, ≈ 200 to ≈ 400 mL/gVS) with organic loading rate of ≈ 0.053 gVS/gVS(reactor) (Day 1-435, SRT 20 days, SRT20) at FA 1g/d (FA1), BA 12 g/d (BA12) and BA 24 g/d (BA24) dosed bioreactors increased after adaptation. BPRs with SRT10 and SRT5 decreased while BPRs with SRT40 showed to increase compared to initial BPRs (≈ 200 mL/gVS) with SRT20. SRT5 operation reduced the BPRs (≈ 10 - ≈ 90 mL/gVS) significantly and only BA12 and BA24 dosed bioreactors could recover the BPRs (≈ 100 - ≈ 200 mL/gVS) after SRT20 operation (Day 613-617) compared to FA1 and FA3 and control. Released levels of Co, Mo and W at BA12 and BA24 dosed bioreactors showed most potential to improve MSW anaerobic digestion.

p53 and Sp1 cooperate to regulate the expression of Epstein-Barr viral Zta protein

Epstein-Barr virus (EBV) belongs to the gammaherpesvirus family. To produce infectious progeny, EBV reactivates from latency into the lytic cycle by expressing the determinative lytic transactivator, Zta. In the presence of histone deacetylase inhibitor (HDACi), p53 is a prerequisite for the initiation of the EBV lytic cycle by facilitating the expression of Zta. In this study, a serial mutational analysis of Zta promoter (Zp) indicated an important role for the ZID element in responding to HDACi induction and p53 binds to this ZID element together with Sp1, a universal transcription factor. Abolition of the DNA-binding ability of Sp1 reduces the inducibility of ZID by HDACi and also reduces the amount of p53 binding to ZID. Finally, it was shown that EBV in p53-positive-lymphoblastoid cell lines (LCLs) can enter into the lytic cycle spontaneously; however, knockdown of p53 in LCLs leads to retardation of EBV reactivation.

Improved chondrogenesis and engineered cartilage formation from TGF-β3-expressing adipose-derived stem cells cultured in the rotating-shaft bioreactor

Adipose-derived stem cells (ASCs) have captured growing interests for cartilage regeneration. Although ASCs chondrogenesis can be stimulated by genetic modification, whether genetically engineered ASCs hold promise for the cartilaginous tissue formation remains to be explored. Since baculovirus (an emerging gene delivery vector) effectively transduced ASCs and transforming growth factor β3 (TGF-β3) was recently shown to induce ASCs chondrogenesis more potently than TGF-β1, we constructed a baculoviral vector (Bac-CT3W) to encode TGF-β3. The Bac-CT3W-transduced ASCs expressed TGF-β3 robustly and substantiated the chondrogenesis of ASCs cultured in monolayer and in porous scaffolds. Culture of the transduced cell/scaffold constructs in the rotating-shaft bioreactor (RSB) under hypoxic and perfusion conditions for 2 weeks further augmented the ASCs chondrogenesis and deposition of cartilage-specific collagen II and glycosaminoglycans, leading to the formation of cartilage-like tissues with hyaline appearance and compressive modulus approaching 62% of the native articular cartilage. Intriguingly, prolonged culture to 3 or 4 weeks failed to further augment the construct growth, probably due to the scaffold degradation. Altogether, baculovirus-mediated TGF-β3 expression in ASCs in conjunction with dynamic culture in the RSB for 2 weeks synergistically ameliorated the ASCs chondrogenesis and formation of cartilaginous tissues, representing a novel approach to producing engineered cartilages.

Effects of micro-nano and non micro-nano MSWI ashes addition on MSW anaerobic digestion

This study aims at investigating the effects of micro-nano municipal solid waste (MSW) incinerator (MSWI) fly ash (FA) and bottom ash (BA) on the MSW anaerobic digestion. Results showed that suitable micro-nano and non micro-nano MSWI ashes addition (FA/MSW 3, 6, 18 and 30 g g(-1) VS and BA/MSW 12, 36, 60 and 120 g g(-1) VS) could enhance the biogas production compared to the control. It was particularly found to have the highest biogas production at the micro-nano MSWI BA/MSW ratio of 36 g g(-1) VS (∼193 mL g(-1) VS MSW, ∼3.5 times to the control). Micro-nano MSWI FA and BA added bioreactors had the higher biogas production than the corresponding non micro-nano MSWI FA and BA added ones. Suitable MSWI ashes addition could improve the biogas production due to the released metals levels suitable for the MSW anaerobic digestion particularly found in the micro-nano added bioreactors.

Effects of spiked metals on the MSW anaerobic digestion

This study aimed to investigate the effects of eight metals on the anaerobic digestion of the organic fraction of municipal solid waste (OFMSW) in bioreactors. Anaerobic bioreactors containing 200 mL MSW mixed completely with 200 m L sludge seeding. Ca and K (0, 1000, 2000 and 6,000 mg L(-1)) and Cr, Ni, Zn, Co, Mo and W (0, 5, 50 and 100 mg  L(-1)) of various dose were added to anaerobic bioreactors to examine their anaerobic digestion performance. Results showed that except K and Zn, Ca (~728 to ~1,461 mg  L(-1)), Cr (~0.0022 to ~0.0212 mg  L(-1)), Ni (~0.801 to ~5.362 mg  L(-1)), Co (~0.148 to ~0.580 mg  L(-1)), Mo (~0.044 to ~52.94 mg  L(-1)) and W (~0.658 to ~40.39 mg  L(-1)) had the potential to enhance the biogas production. On the other hand, except Mo and W, inhibitory concentrations IC(50) of Ca, K, Cr, Ni, Zn and Co were found to be ~3252, ~2097, ~0.124, ~7.239, ~0.482, ~8.625 mg  L(-1), respectively. Eight spiked metals showed that they were adsorbed by MSW to a different extent resulting in different liquid metals levels and potential stimulation and inhibition on MSW anaerobic digestion. These results were discussed and compared to results from literature.

Modeling biogas production from organic fraction of MSW co-digested with MSWI ashes in anaerobic bioreactors

This study aims at investigating the effects of MSW incinerator fly ash (FA) and bottom ash (BA) on the anaerobic co-digestion of OFMSW with FA or BA. It also simulates the biogas production from various dosed and control bioreactors. Results showed that suitable ashes addition (FA/MSW 10 and 20 g L(-1) and BA/MSW 100 g L(-1)) could improve the MSW anaerobic digestion and enhance the biogas production rates. FA/MSW 20 g L(-1) bioreactor had the higher biogas production and rate implying the potential option for MSW anaerobic co-digestion. Modeling studies showed that exponential plot simulated better for FA/MSW 10 g L(-1) and control bioreactors while Gaussian plot was applicable for FA/MSW 20 g L(-1) one. Linear and exponential plot of descending limb both simulated better for BA/MSW 100 g L(-1) bioreactor. Modified Gompertz plot showed higher correlation of biogas accumulation than exponential rise to maximum plot for all bioreactors.

Baculovirus-mediated growth factor expression in dedifferentiated chondrocytes accelerates redifferentiation: effects of combinational transduction

Transduction of partially dedifferentiated rabbit chondrocytes with a baculovirus (Bac-CB) expressing bone morphogenetic protein-2 (BMP-2) reverses dedifferentiation and enhances matrix production. Hereby we examined whether transduction with Bac-CB in combination with another baculovirus expressing transforming growth factor-beta1 (TGF-beta1) or insulin-like growth factor-1 (IGF-1) synergistically augmented chondrogenic differentiation. Passage 3 rabbit articular chondrocytes were transduced by different baculovirus combinations: single transduction with Bac-CB, cotransduction with Bac-CB and Bac-CT (expressing TGF-beta1), cotransduction with Bac-CB and Bac-CI (expressing IGF-1), and transduction with Bac-CB followed by repeated transduction with Bac-CT, Bac-CI, or Bac-CB 5 days later. Transduced cells were encapsulated into alginate beads for culture. Among these strategies, only cotransduction with Bac-CB and Bac-CT led to improved redifferentiation when compared with Bac-CB single transduction, as evidenced by the enhanced expression of aggrecan and collagen IIB (Col IIB), suppressed expression of Col I and Col X, emergence of chondrocyte-specific lacunae, and elevated deposition of matrix molecules. The cotransduction also accelerated the expression of Sox9, Col IIB, and aggrecan. In summary, baculovirus-mediated coexpression of TGF-beta1 and BMP-2 synergistically accelerates the chondrocyte redifferentiation process and improves the maintenance of chondrocyte phenotype and accumulation of cartilage-specific matrix molecules.

Biostabilization assessment of MSW co-disposed with MSWI fly ash in anaerobic bioreactors

Municipal solid waste incinerator (MSWI) fly ash has been examined for possible use as landfill interim cover. For this aim, three anaerobic bioreactors, 1.2m high and 0.2m in diameter, were used to assess the co-digestion or co-disposal performance of MSW and MSWI fly ash. Two bioreactors contained ratios of 10 and 20 g fly ash per liter of MSW (or 0.2 and 0.4 g g(-1) VS, that is, 0.2 and 0.4 g fly ash per gram volatile solids (VS) of MSW). The remaining bioreactor was used as control, without fly ash addition. The results showed that gas production rate was enhanced by the appropriate addition of MSWI fly ash, with a rate of approximately 6.5l day(-1)kg(-1)VS at peak production in the ash-added bioreactors, compared to approximately 4l day(-1)kg(-1)VS in control. Conductivity, alkali metals and VS in leachate were higher in the fly ash-added bioreactors compared to control. The results show that MSW decomposition was maintained throughout at near-neutral pH and might be improved by release of alkali and trace metals from fly ash. Heavy metals exerted no inhibitory effect on MSW digestion in all three bioreactors. These phenomena indicate that proper amounts of MSWI fly ash, co-disposed or co-digested with MSW, could facilitate bacterial activity, digestion efficiency and gas production rates.

Solubility of heavy metals added to MSW

This paper aims to investigate the six heavy metal levels (Cd, Cr, Cu, Pb, Ni and Zn) in municipal solid waste (MSW) at different pHs. It intends to provide the baseline information of metals solubility in MSW co-disposed or co-digested with MSW incinerator ashes in landfill or anaerobic bioreactors or heavy metals contaminated in anaerobic digesters. One milliliter (equal to 1mg) of each metal was added to the 100ml MSW and the batch reactor test was carried out. The results showed that higher HNO3 and NaOH were consumed at extreme pH of 1 and 13 compared to those from pH 2 to 11 due to the comparably higher buffer capacity. Pb was found to have the least soluble level, highest metal adsorption (%) and highest partitioning Kd (lg(-1)) between pH 3 and 12. In contrast, Ni showed the highest soluble level, lowest metal adsorption (%) and lowest Kd (lg(-1)) between pH 4 and 12. Except Ni and Cr, other four metals seemed to show the amphibious properties as comparative higher solubility was found in the acidic and basic conditions.

Modulation of chondrocyte phenotype via baculovirus-mediated growth factor expression

Baculovirus has emerged as a new gene delivery vector thanks to a number of advantages. This study demonstrated that baculovirus conferred efficient gene delivery and mediated expression of growth factors (TGF-beta1, IGF-1 and BMP-2) to therapeutic levels in rabbit chondrocytes. Interestingly, the cellular response to growth factor stimulation was dependent on the cell passage. The highly de-differentiated passage 5 (P5) chondrocytes failed to respond to the stimulation by either growth factor. The de-differentiated P3 cells also failed to maintain the chondrocyte phenotype, but baculovirus-mediated BMP-2 expression remarkably reversed the de-differentiation and enhanced the aggrecan and collagen II production in 2D and 3D cultures, as evidenced by cell morphology, histological staining and gene expression analyses. Baculovirus-mediated TGF-beta1 expression modestly enhanced the cartilage-specific matrix production, although to a lesser extent. Intriguingly, IGF-1, a well-known chondroinductive protein, failed to stimulate the P3 cells likely due to the loss of IGF-1 receptor expression. In summary, this study proved for the first time the potentials of baculovirus in modulating the differentiation status of chondrocytes in the context of cartilage tissue engineering, but also highlighted the importance of selecting appropriate cell passage and growth factor for genetic manipulation.

A facile synthesis of phytosphingosine from diisopropylidene-D-mannofuranose

In the present study, an efficient method with a high overall yield for preparing phytosphingosine and an analogue was developed. Starting with commercially available 2,3;5,6-di-O-isopropylidene-d-mannofuranose, a variety of lipid moieties were incorporated to obtain phytosphingosine and an analogue. Through an eight-step manipulation, phytosphingosine was obtained with an overall yield of 57%.

Cross-limb vascular shunting as an auxiliary to major limb revascularisation

A 40-year-old male motorcyclist suffered a near-total amputation of his right foot. His limb was successfully salvaged with the aid of a cross-leg vascular shunt. Temporary arterial flow from the contralateral limb was transmitted via a pressure monitor tube to perfuse the avulsed part. This allowed the surgeon to carry out unhurried wound debridement, dissection of vital structures and skeletal fixation. The cannulation port was placed well distal to the proposed definitive anas<$>tomosis, to reduce damage to the endothelium. This procedure could be a valuable adjunct in major limb replantation, particularly in cases of prolonged ischaemia.

Positive association of ankylosing spondylitis with homozygous HLA-B2704, but protection with B2705 in Taiwan Chinese

The study was undertaken to determine the effects of HLA-B27 subtypes on susceptibility to ankylosing spondylitis (AS) in Taiwan Chinese, a polymerase chain reaction-restrictive fragment length polymorphism (PCR-RFLP) method was developed for subtyping of HLA-B27. In this series, there are 62 patients with AS who were tested HLA-B27 positive serologically and 738 normal persons over the age of 65. Among the 738 normal controls, 42 (5.7%) were HLA-B27 positive. There were six (14.3%) homozygous for B2704, 18 (42.9%) heterozygous for B2704, 2 (4.8%) double heterozygous for B2704 and B2705, one (2.3%) double heterozygous for B2704 and B2706, 2 (4.8%) homozygous for B2705, 11 (26.1%) heterozygous for B2705, and 2 (4.8%) heterozygous for B2706. In our patients with AS, 37 (59.7%) were homozygous for B2704 and 25 (40.3%) were heterozygous for B2704. The HLA-B27 carrier rate in Taiwan healthy old persons is estimated at 5.7%. Susceptibility to AS is determined by homozygosity for B2704. However, B2705 may be an indicator of protection against AS in Taiwan Chinese.

A novel platelet-rich arterial thrombosis model in rabbits. Simple, reproducible, and dynamic real-time measurement by using double-opposing inverted-sutures model

Though numerous animal thrombosis models have been introduced, an easy, reliable, and reproducible arterial thrombosis model remains a continuing challenge prior to a thrombolytic study. In an effort to evaluate the efficiency of various recombinant thrombolytic agents with specific affinity to activated platelets in vivo, we developed a novel double-opposing inverted-sutures model to create a platelet-rich thrombus in the femoral artery of rabbits. The arteriotomy was done semicircumferentially, and variously sized microsurgical sutures were introduced intraluminally in a double-opposing inverted manner. The animals were divided into three groups according to the double-opposing inverted-sutures used: Group 1 with 10-0 nylon (n=6), Group 2 with 9-0 nylon (n=6), and Group 3 with 8-0 nylon (n=22). The superficial epigastric branch was cannulated with a thin polyethylene (PE) tube for intraarterial administration of the studied thrombolytic agent. The blood flow was continuously measured with a real-time ultrasonic flow meter. Within 2 h of installation of the sutures, there was no thrombus formation in either Group 1 or 2. In Group 3, the thrombosis rate was 91% (20 of 22) under a steady baseline flow (with an average of 12.23+/-2.40 ml/min). It was highly statistically significant with a P-value of .0000743 using Fisher's Exact Test. The averaged time to thrombosis was 21.8+/-9.8 min. The ultrasonic flow meter to record the dynamic real-time measurement of blood flow was a guideline for thrombus formation or dissolution, which was correlated with the morphological findings of stenotic status of the vessel detected by the Doppler sonography. The components of the thrombus were proven to be platelet-rich predominant by histological examination via hematoxylin and eosin (H&E) stain and transmission electron microscopy (TEM). To confirm that the double-opposing inverted-sutures model would be useful for a study of thrombolytic agents, we evaluated the effects of recombinant tissue-type plasminogen activator (rt-PA) and streptokinase-human plasminogen (SK-HPlg). The average time to thrombolysis post rt-PA infusion was 16.0+/-8.2 min and that of SK-HPlg was 79.6+/-23.1, which were similar to the previous reports. In conclusion, the novel double-opposing inverted-sutures (8-0 nylon) model provides a simple, reliable, and reproducible platelet-rich arterial thrombosis model with noninvasive and dynamic real-time measurement. It may be applied in assessing the efficiency of the recombinant thrombolytic agents and offers many advantages of an arterial platelet-rich in vivo thrombosis model.

Long-term effects of sensory reeducation following digital replantation and revascularization

The long-term maintenance of sensory gain following sensory reeducation is still unknown for replanted digits. Ten patients with 18 replanted or revascularized digits, who had received a formal sensory reeducation program for 1.5 years postoperatively, were reevaluated with moving two-point discrimination and Semmes-Weinstein pressure threshold test after discontinuing sensory reeducation for 1 year. Another four patients with seven replanted or revascularized digits, who have never received sensory reeducation after surgery, were also followed up in the same way. After cessation of sensory reeducation, the degree of moving two-point discrimination became significantly worse in the formal sensory-reeducated group (P < 0.05) and significantly improved in the group without sensory reeducation initially (P < 0.05), whereas it showed a nonsignificant change of Semmes-Weinstein threshold both in the group with formal sensory reeducation and without sensory reeducation. Sensory retraining did influence the progressive change of moving two-point discrimination, but not in a parallel way with the Semmes-Weinstein threshold test.

Free anterolateral thigh flap for reconstruction of head and neck defects following cancer ablation

Thirty-seven consecutive free anterolateral thigh flaps in 36 patients were transferred for reconstruction of head and neck defects following cancer ablation between January of 1997 and June of 1998. The success rate was 97 percent (36 of 37), with one flap lost due to a twisted perforator. The anatomic variations and length of the vascular pedicle were investigated to obtain better knowledge of anatomy and to avoid several surgical pitfalls when it is used for head and neck reconstruction. The cutaneous perforators were always found and presented as musculocutaneous or septocutaneous perforators in this series of 37 anterolateral thigh flaps. They were classified into four types according to the perforator derivation and the direction in which it traversed the vastus lateralis muscle. In type I, vertical musculocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 56.8 percent of cases (21 of 37), and they were 4.83 +/- 2.04 cm in length. In type II, horizontal musculocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 27.0 percent of cases (10 of 37), and they were 6.77 +/- 3.48 cm in length. In type III, vertical septocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 10.8 percent of cases (4 of 37), and they were 3.60 +/- 1.47 cm in length. In type IV, horizontal septocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 5.4 percent of cases (2 of 37). They were 7.75 +/- 1.06 cm in length. The average length of vascular pedicle was 12.01 +/- 1.50 cm, and the arterial diameter was around 2.0 to 2.5 mm; two accompanying veins varied from 1.8 to 3.0 mm and were suitable for anastomosis with the neck vessels. Reconstruction of one-layer defect, external skin or intraoral lining, was carried out in 18 cases, through-and-through defect in 17 cases, and composite mandibular defect in two cases. With increasing knowledge of anatomy and refinements of surgical technique, the anterolateral thigh flap can be harvested safely to reconstruct complicated defects of head and neck following cancer ablation with only minimal donor-site morbidity.

Comparison of two-dimensional and three-dimensional techniques for determination of facial motion--absolute movement in a local face frame

BACKGROUND AND PURPOSE

Few studies have used motion analysis in the study of facial animation. A facial animation model using an expert vision motion analysis system was developed in this study to quantitatively evaluate absolute movement during five facial animations.

METHODS

Skin markers were adhered to the face of each subject at 16 anatomic landmarks selected to represent the functional movement of the facial muscles. Three of the 16 skin markers were used to establish a local face frame with the origin in the mid-point of the face. All of the coordinates measured in the laboratory frame were rotated and translated to the local face frame for analysis. The trajectory of the facial markers was evaluated from the local face frame when comparing two-dimensional (2-D) displacement of skin markers (frontal plane) with three-dimensional (3-D) values by paired Student's t-test.

RESULTS

Although the correlation of 2-D and 3-D displacements of skin markers was high (r > 0.69), the differences between 2-D and 3-D motion were significant (p < 0.001). The 2-D displacement of skin markers underestimated the 3-D facial animation in each marker and animation. There were no significant differences in the movement of both mouth angles or of the eyes. Thirty repeated measurements of a subject revealed good concentration in 3-D displacement, velocity, and angle of movement in smiling. The measurement error was less than 0.06 mm. The normative displacement of individual anatomic landmarks was evaluated to avoid size differences of individual faces.

CONCLUSIONS

We suggest that the expert vision motion analysis technique is feasible for quantitative evaluation of absolute facial movement and would be useful for further clinical evaluation of patients with facial palsy.

The use of the motion analysis system for evaluation of loss of movement in the finger

We have used the motion analysis system to measure loss of finger movement after injury. The motion analysis system can provide information about the dynamic angular changes of each finger joint and the fingertip motion area for the injured finger. The latter can be used to calculate the percentage of fingertip motion area preserved. A stiff finger may show limited fingertip motion area with the finger joints tending to flex and extend together.

A simple splinting method for correction of supple congenital clasped thumbs in infants

A splint has been designed to correct the congenital clasped thumb. It is like a short opponens splint that can keep the thumb in a position of abduction and extension without limiting wrist movement. The application of the splint was easy and adjustment for fit could be made at each visit if necessary. The device has been used in 11 infant patients (17 thumbs) with congenital clasped thumb of the supple type. The functional results were excellent in 15 of 17 thumbs, and the other two were good according to the grading system of Weckesser et al. (1968).

The motion analysis system and goniometry of the finger joints

The application of a video-based motion analysis system for goniometry of finger joints during measurement of the fingertip motion area has been assessed. The results indicate that the motion analysis system is reliable for angular measurements of finger joints that are comparable with those obtained by conventional goniometer. The advantages of using the motion analysis system is that it can record and show the changes in angle of all finger joints continuously during finger motion.