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Biomedical subjects

P Y Yang

Publications and source records attributed to P Y Yang.

At least 19 recordsLinked to original sources
PubMed2006

Intermittently aerated EMMC-Biobarrel (entrapped mixed microbial cell with Bio-barrel) process for concurrent organic and nitrogen removal.

The PEMMC-Biobarrel (packed-bed of entrapped mixed microbial cells with Bio-barrel) process and MEMMC-Biobarrel (moving EMMC-Biobarrel) process were investigated for enhancing concurrent organic and nitrogen removal with applied intermittent aeration. For the PEMMC-Biobarrel process, the EMMC-Biobarrel carriers were employed at a packing ratio of 20%. In the MEMMC-Biobarrel process, the EMMC-Biobarrel carriers with a packing ratio of 10% were added along with the activated sludge (AS) in the bioreactor. Three different hydraulic retention times (HRTs) of 9, 6 and 4 h were applied. Aeration was provided intermittently at time schedules of 1 h air on/1 h air off, 1 h on/1.5 h off and 1 h on/2 h off. Nitrogen removal in the PEMMC-Biobarrel system was not improved by increasing the intermittent non-aeration time period. On the other hand, the MEMMC-Biobarrel process enhanced nitrogen removal with increasing non-aeration time even though the SCOD/N(TIN) ratio decreased from 6 to 4. Significant denitrification during the aeration cycle was observed in the MEMMC-Biobarrel process. The MEMMC-Biobarrel process demonstrated the most efficient organic and nitrogen removal at an HRT of 6 h with an intermittent aeration time schedule of 1 h on/2 h off. Nitrogen removal of 80% was achieved, which was about 15% higher compared to the AS system. TCOD and SCOD removal efficiencies were 80% and 75%, respectively.

Biodegradation, Environmental↗
PubMed2006

Development of an effective sample preparation approach for proteomic analysis of silkworm eggs using two-dimensional gel electrophoresis and mass spectrometry.

Sample preparation is still the first and important step toward successful two-dimensional gel electrophoresis (2DE) and identification in proteomics study. The 2DE profiling of eggs of silkworm species by using conventional one-step extraction, however, is unsatisfactory because high-abundance proteins such as egg-specific protein (ESP) and No 30 family (30 KP) in the extract lead to difficulties in detecting most of biologically relevant proteins. Based on the tendency of these abundant proteins to be soluble in Tris-HCl buffer, we report herein a robust approach in which the extract enriched in ESP and 30 KP was fractionationed and mixed with the re-extract of residual pellet in an optimal proportion. In comparison with the one-step method, the 2DE pattern was improved by this new method with over one-third enhancement in spots. A total of 48 unique proteins obtained have been furthermore identified by mass spectrometry (MS) and MS/MS. The identified proteins are found to include heat shock proteins families, ribosomal proteins, disulfide isomerase proteins, Glutathione S-transferase, and elongation factor, etc., which are mainly involved in some important processes. To our knowledge, this is the first time that the several proteins have been detected in silkworm eggs by proteomics means. This simple and reproducible approach would raise the opportunity of discovering and identifying more biomarkers and determining their possible roles in further studies.

Animals↗
PubMed2006

Comparative proteome analysis of rat brain and coronary microvascular endothelial cells.

The endothelium of different organs displays a remarkable heterogeneity, although it presents many common functional and morphological features. However, despite our knowledge of heterogeneity among endothelial cells from different sites, the differences between brain microvascular endothelial cells (BMEC) and coronary microvascular endothelial cells (CMEC) are poorly defined. The aim of this study was to investigate whether BMEC are distinct from CMEC at the protein level. Using the proteomic approach, we comparatively analyzed the proteome of cultured BMEC and CMEC. We reproducibly separated over 2000 polypeptides by using two-dimensional electrophoresis (2-DE) at pH range of 3-10. Using PDQuest software to process the 2-DE gel images, forty-seven protein spots were differentially expressed in the two-endothelial cells. Of these, thirty-five proteins are highly expressed in BMEC, whereas twelve proteins are highly expressed in CMEC. Fifteen proteins in BMEC and seven proteins in CMEC were identified with high confidence by matrix-associated laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS). Our data suggested that BMEC and CMEC were different in several aspects including cytokine and growth-related molecules, stress-related proteins, metabolic enzymes, signal transduction proteins and others. The identification of a set of proteins preferentially expressed in BMEC and CMEC provided new data on the heterogeneity of the endothelium.

Animals↗
PubMed2006

Bio-anaerobic treatability study for PCBs-contaminated oil.

This study investigated the bio-treatability of PCB contaminated oil for the development of design and operational parameters for the bioreactor. Input of external carbon and nutrient source in the aqueous phase was found to be required for the treatment of polychlorinated biphenyls (PCBs)-contaminated oil. Addition of surfactant was investigated for the emulsification of oil to reduce interference of contact with microorganisms and PCBs. The ratio of surfactant to oil was empirically optimized to 1 : 1. The higher PCB removal efficiency was obtained at 30 days of hydraulic retention time (HRT) in the semi-batch reactor study without cell recycle. The removal efficiency measured in mixed liquor was maintained at over 85% on average at 32 +/- 2 degrees C and 30% at 22 +/- 2 degrees C. More than 0.2 g/l/d of the organic loading rate was suggested to be maintained for various PCB loading rates (0.02-0.6 mg-PCB/l/d). For high biomass retaining and easy collection of treated oil, an Anaerobic Sequencing Batch Reactor (ASBR) was investigated. The removal of Aroclor was observed as more than 50% in the oil phase with 3 days reaction time and about 40% in overall phases, i.e. oil, liquid, biomass phases at 22 +/- 2 degrees C. US EPA verification results on the process performance are included in this presentation.

Bacteria, Anaerobic↗
PubMed2004

Two-stage entrapped mixed microbial cell process for simultaneous removal of organics and nitrogen for rural domestic sewage application.

A two-stage entrapped mixed microbial cell ((2S)EMMC) process which separates nitrification and denitrification phases by the installation of the anoxic and oxic EMMC reactors packed with EMMC carriers was operated with 6, 4, 3, and 2 hours of hydraulic retention time (HRT) using simulated domestic wastewater. The activated sludge was immobilized using cellulose acetate for the EMMC carriers. Similar soluble chemical oxygen demand (SCOD) removal efficiencies of 90-97% were observed for all HRTs (SCOD loading rate of 0.84-2.30 g/L/d) applied. In order to achieve more than 80% of TN removal efficiency, the HRT should be maintained higher than 4 hours (less than 0.24 g/L/d of TN loading rate). Denitrification was a rate-limiting step which controlled overall TN removal efficiency at TN loading rate of 0.15-0.31 g/L/d although nitrification efficiencies achieved 97-99%. The effluent TSS of less than 25 mg/L in the (2S)EMMC process was maintained at the SCOD loading rate of less than 1.23 g/L/d with back-washing intervals of 5 and 10 days in the anoxic and oxic EMMC reactors, respectively. The minimum HRT of 4 hours is required for high removal efficiencies of organics (average 95.6%) and nitrogen (average 80.5%) in the (2S)EMMC process with 3 times of recirculation ratio.

Bioreactors↗
PubMed2003

EMMC process for combined removal of organics, nitrogen and an odor producing substance.

In order to improve the process performance regarding the removal of organics, nitrogen, and an odor-causing compound (sulfide) contained in domestic wastewater, an entrapped-mixed-microbial cell (EMMC) with and without humic substances for both fixed and moving carrier reactors and conventional suspended growth culture (i.e. conventional activated sludge process) were investigated simultaneously. Both synthetic (simulated to the organics concentration of general domestic sewage) and actual domestic wastewater were investigated under operational conditions of 12 h of hydraulic retention time (HRT) with 1 h of aeration and 1 h of non-aeration, and 6 h of HRT with continuous aeration, at a room temperature of 25 +/- 2 degrees C. It was found that entrapping humic substances in the EMMC carriers had no impact on the removal of organics, nitrogen, and the odor-producing compound. Additionally, the performance of the EMMC moving carrier system for the removal of these pollutants is similar to that of the EMMC fixed carrier system. In general, the EMMC associated systems which provide high solids retention time achieve a better removal of chemical oxygen demand (COD), nitrogen, and the odor-producing substance than the suspended growth system for both HRTs of 6 h (continuous aeration) and 12 h (1 h of aeration and 1 h of non-aeration). Both the fixed and moving carrier EMMC processes, therefore, have the potential for improvement or replacement of the existing conventional activated sludge process with regard to improving the effluent qualities (such as COD, nitrogen and odor-producing compound) for reuse/disposal.

Ammonia↗
PubMed2003

Integrating entrapped mixed microbial cell (EMMC) process for biological removal of carbon and nitrogen from dilute swine wastewater.

An entrapped mixed microbial cells (EMMC) process was used to investigate the simultaneous removal of carbon and nitrogen from dilute swine wastewater. Cellulose triacetate was used as the matrix for entrapping the mixed microbial cells. The EMMC process was tested with various oxygen supply conditions (ratios of aeration to non-aeration times) and two types of carrier sizes (large and medium). Also, various pre-treatments with chemical coagulation, screen separation and ammonium crystallization prior to the EMMC process, and post-treatment after the EMMC process were investigated. It was found that at a hydraulic retention time of 30 h and one hour of aeration and one hour of non-aeration, the EMMC process packed with medium carriers after the pretreatment of ammonium crystallization, exhibited the best total nitrogen removal efficiency of 95.1 +/- 1.0% when compared to the other two pre-treatment methods. The total chemical oxygen demand (TCOD) and soluble chemical oxygen demand removal efficiencies were 83.5 +/- 2.2% and 84.1 +/- 1.1%, respectively. Lime post-treatment provided TCOD and total phosphorus removal efficiencies of 59.6 +/- 2.7% and 98.0 +/- 0.5%, respectively. Thus, a cost analysis for ammonium crystallization pre-treatment, EMMC process, and post-treatment with lime was conducted. The unit cost for a 2000 pig operation is approximately dollars 4.91/pig/year. For the application of the EMMC process with the proposed pre- and post-treatments, a suitable farm size needs to be greater than a 2000 pig operation. Because of the high efficiency and the simple operation of simultaneous carbon and nitrogen removal, the EMMC process has the potential for treatment of dilute swine wastewater in a land-limited area and can be manufactured as pre-fabricated wastewater treatment units.

Animals↗
PubMed2003

Catalytic ozonation of 2-dichlorophenol by metallic ions.

This research is mainly to explore functional improvement by adding various kinds of metallic ions in the ozonation of 2-chlorophenol solution. During the experiment, various kinds of metallic ions (Pb+, Cu2+, Zn2+, Fe2+, Ti2+, and Mn2+) were added; it was found that the reaction rate increased in all cases. The best result was obtained by using manganese ions, followed by iron and titanium ions. At pH = 3 and 1 ppm Mn2+ concentration, the reaction rate was increased by three times. TOC removal rate was also increased from 12.6% to 38% at 60 min reaction time. Ozone self-decomposition with various kinds of metallic ions alone was tested. It was found the ozone self-decomposition coefficient is highly dependent on the reaction rate constant for ozonation of 2-chlorophenol. The improvement of reaction was relevant to the mechanism of reaction between ozone and metallic ions. Furthermore, the effect of adding manganese ions was studied. With the initial manganese concentration at 0-2 ppm, after gas exposure for 20 min the removal rate can be increased from 38% to 93%. TOC removal rate was increased from 11% to 38%. The reaction rate was improved more greatly at the initial pH = 3.

Catalysis↗
PubMed2002

Levels of interferon-gamma and interleukin-2 receptor-alpha for bronchoalveolar lavage fluid and serum were correlated with clinical grade and treatment of pulmonary tuberculosis.

OBJECTIVE: We investigated possible correlations for interferon-gamma (IFN-gamma) and soluble interleukin-2 receptor-alpha (sIL-2R-alpha) levels in bronchoalveolar lavage fluid (BALF), and clinical grade of pulmonary tuberculosis (TB), which is determined by factors such as extent of pulmonary involvement, fever and loss of body weight. DESIGN: In order to explore these correlations and address associated questions, BALF was collected from 45 patients presenting with active pulmonary TB and 14 healthy controls. Repetitive BALF was collected in 17 patients after 3 months of anti-tuberculosis chemotherapy. The epithelial lining fluid (ELF) levels for IFN-gamma and sIL-2R-alpha were measured using enzyme-linked immunosorbent assay (ELISA) after standardization with urea. RESULTS: Patients with higher-grade pulmonary TB (i.e., with more advanced pulmonary involvement, fever or body weight loss), revealed significantly higher ELF levels for IFN-gamma and sIL-2R-alpha compared to those with lower grade pulmonary TB. Similar results were also determined for sIL-2R-alpha serum levels, but not for IFN-gamma serum levels. After anti-tuberculosis chemotherapy the elevated cytokine levels for ELF and serum significantly decreased in accordance with radiographic improvement. CONCLUSIONS: ELF levels of IFN-gamma and sIL-2R-alpha were correlated with disease grading of pulmonary TB and decreased after anti-tuberculosis chemotherapy.

Bronchoalveolar Lavage Fluid↗
PubMed2001

Klebsiella pneumoniae bacteremia: community-acquired vs. nosocomial infections.

BACKGROUND: This study attempted to determine the clinical manifestations and influential factors affecting the prognosis of patients with community-acquired and nosocomial bacteremia of Klebsiella pneumoniae (K. pneumoniae). METHODS: We retrospectively reviewed the medical records of 211 patients who had a clinically significant episode of K. pneumoniae bacteremia from January 1997 until December 1999. RESULTS: Most reports describe K. pneumoniae bacteremia as typically nosocomial, but in our study approximately 3 of 4 episodes were community-acquired. Without including "unknown origin", the most common infectious site for both community-acquired and nosocomial bacteremia was the hepatobiliary tract. The overall mortality for all 211 patients with K. pneumoniae bacteremia was 25.1%. Significantly higher mortality rates occurred in patients who were elderly (> 65 years), had a nosocomial infection, for whom the respiratory tract was the portal of entry, and ultimately fatal conditions or acute complications were due to shock or renal insufficiency. CONCLUSIONS: Patients with community-acquired and nosocomial bacteremia had different types of underlying diseases. Isolates from nosocomial infections were significantly more frequently resistant to aminoglycosides, antipseudomonal penicillin, and all three generations of cephalosporins. In this regard, an aggressive empirical therapeutic approach to infections of K. pneumoniae is suggested.

Adult↗
PubMed2000

Carbofuran-induced delayed neuropathy.

BACKGROUND: Although carbamates have been widely used in the world for many years, carbamate-induced delayed neuropathy is rare. We report what appears to be delayed neuropathy caused by poisoning with carbofuran, a cholinesterase-inhibiting carbamate, although the certainty of diagnosis is somewhat limited by the lack of a sural nerve biopsy and spinal fluid examination. CASE REPORT: A 23-year-old man attempted suicide by ingesting 100 mL of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate). After recovering from acute cholinergic toxicity, he had notable paresthesia in his lower limbs and difficulty walking. Electrophysiologic findings revealed sensorimotor neuropathy. Recovery began at 1 week and continued for 4 months. A similar delayed neuropathy has been described with carbamate, 1-naphthyl N-methylcarbamate, and m-tolyl methylcarbamate, but not with carbofuran insecticides.

Adult↗
PubMed2000

Transplant of cultured autologous pure melanocytes after laser-abrasion for the treatment of segmental vitiligo.

Segmental vitiligo is a special type of vitiligo with unilateral distribution of lesions and has a stable course. Clinically, many patients with segmental vitiligo have unsatisfactory responses to topical corticosteroid or UV phototherapy. We have developed a technique for the isolation of melanocytes from a small specimen of normally pigmented skin obtained via a suction blister. The melanocytes can be proliferated in culture and then replanted onto laser-abrased vitiliginous areas. We used this procedure to treat 25 patients with segmental vitiligo that were refractory to medical therapy. The repigmented portion of the total treated area amounted to 95-100% in 21 patients and 65 to 94% in 4 patients. The response rate to treatment was 100% in this study. No scarring or other side-effects developed. The results of this study demonstrate that this method is a valuable tool for the treatment of patients with segmental vitiligo.

Adolescent↗
PubMed2000

Fatal and non-fatal chromobacterial septicemia: report of two cases.

Chromobacterium violaceum is frequently found in soil and water in tropical and subtropical regions. The organism rarely causes infection in humans, but is associated with a high mortality rate when it occurs. Septicemia associated with abscess in multiple organs such as the liver, skin, lungs, spleen, lymph nodes, and brain has been reported. We report on 2 patients with systemic infections with Chromobacterium violaceum. One presented with a fulminant course with multiple organ involvement and died 78 days later. The other presented with a milder course and survived after antibiotic therapy. In conclusion, infection with Chromobacterium violaceum is rare but its course is usually fulminant with high mortality especially in patients with sepsis and multiple organ involvement. We hope this report will provide additional information to physicians in the treatment of this disease.

Adult↗
PubMed1999

In-shoe pressure measurements with a viscoelastic heel orthosis.

OBJECTIVE: To detect the mechanical effect of a viscoelastic heel orthosis. DESIGN: Two-factor analysis of variance with interactions between the orthosis and the subjects. The number of subjects was determined by presuming the effect of the orthosis to be twice as large as the error-free standard deviation (SD) of the interactions, the step-to-step SD four times as large as the error-free SD of the interactions, type 1 error probability equal to .05, and type 2 error probability equal to .20. SETTING: A gait laboratory in a university hospital. SUBJECTS: Twenty-two consecutive patients with treated heel pain. MAIN OUTCOME MEASURES: Peak pressure (PP), pressure-time integral (PTI), and foot-to-sensor contact time (CoT) measured for five steps at 24 discrete sensors of predetermined positions in the foot with treated heel pain. RESULTS: The orthosis reduced PPs, PTIs, and CoT (p < .05) in the median midfoot and lateral midfoot; reduced PPs and PTIs (p < .05) in the posterior heel and medial midfoot; increased PP and PTI (p < .05) in the anterior part of the first metatarsal head; and increased PTI (p < .05) in the lateral part of the hallux. The ratios of the estimated step-to-step SDs to the estimated error-free SDs of the interactions of PPs, PTIs, and CoT were less than four at all the sensors. CONCLUSION: Proper design and estimation of the variations ensured that there was sufficient power to detect the effect of an a priori specified size as statistically significant: the orthosis reduced the mechanical loads in the posterior heel and the midfoot and increased the mechanical loads in the anterior part of the first metatarsal head and the lateral part of the hallux during walking.

Adult↗
PubMed1999

Development of a prefabricated treatment plant for diluted pig wastewater.

In order to develop a prefabricated treatment and reuse plant for diluted pig wastewater, an entrapped-mixed-microbial-cell (EMMC) process was evaluated for its process performance and economic analysis. At the hydraulic retention time (HRT) of 30 hrs (loading rate of 1.0 g TCOD/L/d) and intermittent aeration of 1 hr of aeration and 1 hr of non-aeration, it was found that, by using the pretreatment of the ammonium crystallization, both the medium and large carriers were able to reduce TCOD, SCOD, and T-N by 83.51, 84.11, and 95.10%, respectively. The EMMC unit and lime post-treatment followed by ammonium crystallization can reduce BOD5, TCOD, SCOD, TSS, T-N, and T-P, respectively by 99.22, 93.85, 92.67, 97.73, 96.43, and 97.27%. The treated wastewater, after disinfection, is able to meet the requirements of the standards issued by the USEPA for reuse of food crops. The economic analysis indicates that based on the process performance of the EMMC unit, a prefabricated wastewater treatment plant for 2000 pigs has comparable net present worth (NPW) comparing intermittent aerated biological systems and less operation and maintenance and land requirement than conventional biological processes for removal carbon and nitrogen. A farm operation of more than 2000 pigs meets the unit cost of US$4.91/pig/yr. This will minimize the problems pertaining to technical factors or considerations that heavily influence planning, construction and operation of a pig wastewater treatment system.

Animals↗
PubMed1999

Aberrant infrarenal inferior vena cava as a hindrance to percutaneous transvenous mitral valvuloplasty in a patient with mitral stenosis: case report.

Cardiac catheterization and percutaneous transvenous mitral commissurotomy using the Inoue technique were attempted in a 44-year-old woman with mitral stenosis. The pulmonary arterial wedge pressure was 25 mmHg, mean transmitral diastolic pressure gradient 20.3 mmHg, cardiac index 1.80 L/min/m2, and mitral valve area 0.70 cm2. After the diagnostic catheterization, the guide wire for the transseptal procedure was checked in the middle of the inferior vena cava (IVC). A 7-French end-holed Bermann catheter was then used to detect the course of the IVC. It was found that the IVC coursed along the left border of the 4th and 5th lumbar vertebrae, to the left of the abdominal aorta. At the upper border of the third lumbar vertebra, the IVC returned to the right side of the vertebra. In consideration of the inability to pass the Brockenbrough needle through the detoured infrarenal IVC and the risk of rupturing the vessel, the transseptal procedure and attempted percutaneous transvenous mitral commissurotomy were aborted. Therefore, the patient underwent open mitral commissurotomy instead.

Adult↗
PubMed1998

Identification of a novel strain of hepatitis E virus responsible for sporadic acute hepatitis in Taiwan.

Hepatitis caused by the hepatitis E virus (HEV) is a self-limited disease and occurs most frequently as epidemic or sporadic hepatitis in developing countries. The role of HEV in sporadic acute hepatitis in areas without a history of hepatitis E epidemics is obscure. Recently, it was found that more than 10% of the patients with acute non-A, non-B, non-C hepatitis in Taiwan were associated with an acute HEV infection. Nucleotide sequences of the regions within the first open reading frame of HEV were determined in four cases and were 96.7-100% identical to each other. As compared to the isolates from China, Pakistan, Burma, India, Africa, and Mexico, the similarities were, however, only 71.7-79.3%. Phylogenetic analysis revealed that the four Taiwan isolates were categorized as a novel HEV group (the Taiwan strain), which was distinct from all of the strains isolated from other parts of the world. In addition, the isolates from China, Burma, India, and Pakistan were catalogued as the second genotype of HEV (the Asian strain), and the Mexican isolate as the third (the Mexican strain). The African isolate was more related to the Asian type and might be a subtype of the Asian strain. A simple genotyping method by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) is described. The findings also support the hypothesis that HEV may be responsible for some sporadic acute non-A, non-B, non-C hepatitis in other developed countries.

Base Sequence↗