Real-world evaluation of persistence, effectiveness and usage patterns of tofacitinib in treatment of psoriatic arthritis in Australia

OBJECTIVES

To describe treatment patterns and persistence of tofacitinib, interleukin 17 inhibitors (IL-17Ai) and tumour necrosis factor inhibitors (TNFi), in patients with psoriatic arthritis (PsA).

METHODS

Data from adult patients with PsA and who had received at least one prescription of tofacitinib, IL-17Ai or TNFi between May 2019 and September 2021 were sourced from the Australian OPAL dataset. Persistence, analysed via Kaplan-Meier methods, and propensity score matching between tofacitinib and bDMARD (IL-17Ai and TNFi) groups were conducted.

RESULTS

Of 16,692 patients with PsA, 1486 (n = 406 tofacitinib, n = 416 IL-17Ai and n = 664 TNFi) were included. More females were in the tofacitinib group (75.4%) than in the IL-17Ai (61.1%) and TNFi (64.8%) groups. Overall, 19.2% of tofacitinib patients were first line, compared with 41.8% of IL-17Ai and 62.8% of TNFi patients. In the overall population, the median persistence was 16.5 months (95% CI 13.8 to 19.5 months), 17.7 months (95% CI 15.8 to 19.6 months) and 17.2 months (95% CI 14.9 to 20.5 months) in the tofacitinib, IL-17Ai and TNFi groups, respectively. Persistence was similar in the tofacitinib/IL-17Ai matched population; however, in the tofacitinib/TNFi matched population, persistence was longer in the tofacitinib group (18.7 months, 95% CI 15.6 to 21.4 months) compared with the TNFi group (12.2 months, 95% CI 19.9 to 14.9 months).

CONCLUSIONS

In this Australian real-world dataset, tofacitinib was more frequently used in later lines and among a slightly higher proportion of female patients than IL-17Ai or TNFi. Overall, treatment persistence was similar for tofacitinib, IL-17Ai and TNFi, but tofacitinib exhibited longer persistence than TNFi in a matched population. Key Points • This is the first, large real-world study from Australia investigating the demographics, treatment patterns and comparative treatment persistence of patients with psoriatic arthritis (PsA) treated with tofacitinib and biologic disease-modifying drugs (bDMARDs). • The study suggests that tofacitinib is an effective intervention in PsA with at least comparable persistence to bDMARDs: tumour necrosis factor inhibitors (TNFi) and interleukin-17 A inhibitors (IL-17Ai).

Patient Perceptions of Psoriatic Arthritis Management and Communication with Physicians in Australia: Results from a Patient Survey

Introduction

The objective of this report was to evaluate perceptions of psoriatic arthritis (PsA) treatment and satisfaction with healthcare professional (HCP) communication among patients with PsA in Australia, compared with overall global perceptions.

Methods

Data were collected via a global and country-specific survey (The Harris Poll; November 2, 2017–March 12, 2018). Eligible patients were ≥ 18 years old, had been diagnosed with PsA > 1 year prior, had seen a rheumatologist or dermatologist within the past 12 months, and had previously received ≥ 1 conventional synthetic or biologic disease-modifying antirheumatic drug. Data reported by patients included baseline demographics, overall health, time since PsA diagnosis, PsA severity, satisfaction with current PsA medication and management, and experiences regarding communication with their HCP. Descriptive statistics were obtained.

Results

Most patients in Australia were very or somewhat satisfied with their PsA medication, and reported always or often taking their medication exactly as directed by their HCP. However, the majority still experienced symptoms, reported their overall health as poor or fair, and would change something about their PsA medication. While the majority of patients in Australia were satisfied with the communication with their HCP, most would prefer increased communication but some felt that asking too many questions would affect the quality of their care. Perceptions in Australia were similar to global perceptions.

Conclusions

Although most patients with PsA in Australia were satisfied with their disease management and communication with their HCP, many still experienced symptoms, would change something about their PsA medication, and would prefer increased communication with their HCP.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-021-00297-w.

Psoriatic arthritis (PsA) can cause tender and swollen joints. If not treated properly, the joint damage can get worse, until patients struggle to cope with everyday tasks. Patients and their doctors need to communicate well to successfully manage PsA. We used an online survey to ask patients in Australia how they feel about their PsA medication and the way they communicate with their doctor. These patients were adults who had had PsA for more than 1 year, had seen a specialist doctor in the past year, and had taken one or more prescription PsA medications. A total of 152 patients in Australia completed the survey. Most patients were very or somewhat satisfied with the PsA medication they were taking, and most always or often took it exactly as their doctor told them to. However, almost all patients still had symptoms, most said their overall health was poor or fair, and most would like to change something about their medication. While most patients were satisfied with the communication with their doctor about PsA, most wished they talked more with their doctor about their PsA and treatment goals, but some felt that asking too many questions would harm their quality of care. Patients in Australia had similar answers to patients who answered the survey in other countries. Although the survey was limited by the number of patients who responded, and whether patients answered questions properly, it suggests that patients and doctors need to communicate more closely to improve PsA management.

Development of platinum supported on single-walled carbon nanotubes by deposition-precipitation for microbial fuel cells

Microbial fuel cells (MFCs) are an ecologically friendly technology that can recover electricity and simultaneously treat wastewater. Among all the influential factors, cathode material and catalyst play a crucial role in electricity production and oxygen reduction. In this study, Pt nanocatalysts deposited on single-walled carbon nanotubes (Pt/SWCNTs) were synthesized by the deposition-precipitation (DP) method under optimal conditions. The results show that DP might be a promising method for the preparation of Pt/SWCNTs due to its simple, cost-effective and time-saving procedure, in addition to being highly efficient at creating small Pt particles (0.9 nm) that were very uniformly distributed. The synthesized Pt/SWCNTs suspension was spray-coated on to carbon cloth and then used as a cathode for MFCs. The electricity generation of MFCs equipped with a Pt/SWCNTs cathode was evaluated in terms of open circuit voltage (0.6954 V), internal resistance (63.3 Ω•m²) and maximum power density (2,022 mW/m²). The chemical oxygen demand removal, biological oxygen demand removal, total dissolved solids removal, total suspended solids removal and silver recovery was satisfactory at 84.5%, 74.0%, 45.7%, 60.0% and 99.0%, respectively. Therefore, Pt/SWCNTs from the DP method was identified as a potential candidate to replace commercial Pt-carbon cloth for MFC cathodes.

Psychometric Evaluation of Patient Satisfaction with a Fast Track Protocol Driven Service

Introduction

We aimed to develop a questionnaire with psychometric evidence of reliability and validity to evaluate patient satisfaction with a Fast Track Protocol Driven Service, which was developed to shorten the waiting time and improve the outcome of selected groups of patients. Such patients were initially managed by well-trained nurses according to defined protocols and backed up by experienced medical practitioners. We would like to evaluate their satisfaction because traditionally patients used to be managed by doctors.

Methods

We collected data from 199 subjects from July 2014 to February 2015 using a questionnaire consisting of 24 questions. The subjects were given the questionnaire after receiving treatment and they filled in the questionnaire on sole voluntary basis. These 24 items were subject to Principal Component Analysis. The number of components to be extracted depended on the Eigenvalue. We utilised Varimax rotation for further interpretation and determined which question belonged to which component. We then assessed the internal consistency of each component by calculating Cronbach's alpha. Finally we calculated the mean score for each subscale.

Results

Three components were extracted with good internal consistency, namely “Clinical care”, “Negligence” and “Comprehensiveness”. The mean score for the above components was 43.15, 11.27 and 9.62 respectively. They proved good patient satisfaction in all three aspects.

Conclusions

We have developed a questionnaire with reliability and validity for evaluation of patient satisfaction with our service. The data of our survey shows that our patients are satisfied in the three aspects namely “Clinical care”, “Negligence” and “Comprehensiveness” statistically. (Hong Kong j. emerg.med. 2016;23:12-16)

The association between weight perception and BMI: report and measurement data from the growing up in Ireland Cohort Study of 9-year olds

BACKGROUND

The gold standard for categorisation of weight status is clinically measured body mass index (BMI), but this is often not practical in large epidemiological studies.

OBJECTIVES

To determine if a child's weight perception or a mother's perception of a child's weight status is a viable alternative to measured height and weight in determining BMI classification. Secondary outcomes are to determine the influence of a mother's BMI on her ability to categorise the child's BMI and a child's ability to recognise his/her own BMI.

METHODS

Cross-sectional analysis of the growing up in Ireland cohort study, a nationally representative cohort of 8568 9-year-old children. The variables considered for this analysis are the child's gender, BMI (International Obesity Taskforce grade derived from measured height and weight) and self-perceived weight status, and the mother's weight perception of the child, BMI (derived from measured height and weight) and self-perceived weight status. Cohen's weighted-kappa was used to evaluate the strength of the agreement between pairwise combinations of the BMI variables. Cumulative and adjacent categories logistic regression were used to predict how likely a person rates themselves as under, normal or overweight, based on explanatory variables.

RESULTS

Mothers are more accurate at correctly classifying their child's BMI (κ=0.5; confidence intervals (CI) 0.38-0.51) than the children themselves (κ=0.25; CI 0.23-0.26). Overweight mothers are better raters of their child's BMI (κ=0.51; CI 0.49-0.54), compared with normal (κ=0.44; CI 0.41-0.47) or underweight mothers (κ=0.4; CI 0.22-0.58), regardless of whether the mother's BMI is derived from measured height and weight or self-perceived. The mother's perception of the child's weight status is not an influencing factor on the child's ability to correctly classify him/herself, but the child's self-perceived weight status influences the mother's ability to correctly classify the child.

CONCLUSIONS

A mother's BMI classification of her child is a viable alternative to BMI measurement in large epidemiological studies.

Doxycycline reduces the migration of tuberous sclerosis complex-2 null cells - effects on RhoA-GTPase and focal adhesion kinase

Lymphangioleiomyomatosis (LAM) is associated with dysfunction of the tuberous sclerosis complex (TSC) leading to enhanced cell proliferation and migration. This study aims to examine whether doxycycline, a tetracycline antibiotic, can inhibit the enhanced migration of TSC2-deficient cells, identify signalling pathways through which doxycycline works and to assess the effectiveness of combining doxycycline with rapamycin (mammalian target of rapamycin complex 1 inhibitor) in controlling cell migration, proliferation and wound closure. TSC2-positive and TSC2-negative mouse embryonic fibroblasts (MEF), 323-TSC2-positive and 323-TSC2-null MEF and Eker rat uterine leiomyoma (ELT3) cells were treated with doxycycline or rapamycin alone, or in combination. Migration, wound closure and proliferation were assessed using a transwell migration assay, time-lapse microscopy and manual cell counts respectively. RhoA-GTPase activity, phosphorylation of p70S6 kinase (p70S6K) and focal adhesion kinase (FAK) in TSC2-negative MEF treated with doxycycline were examined using ELISA and immunoblotting techniques. The enhanced migration of TSC2-null cells was reduced by doxycycline at concentrations as low as 20 pM, while the rate of wound closure was reduced at 2–59 μM. Doxycycline decreased RhoA-GTPase activity and phosphorylation of FAK in these cells but had no effect on the phosphorylation of p70S6K, ERK1/2 or AKT. Combining doxycycline with rapamycin significantly reduced the rate of wound closure at lower concentrations than achieved with either drug alone. This study shows that doxycycline inhibits TSC2-null cell migration. Thus doxycycline has potential as an anti-migratory agent in the treatment of diseases with TSC2 dysfunction.

Acanthosis nigricans in obese Chinese children

OBJECTIVES. To investigate the demographic characteristics and insulin resistance in local overweight/obese Chinese children with and without acanthosis nigricans, and the associations of acanthosis nigricans with insulin resistance and other cardiometabolic co-morbidities. DESIGN. Case series with cross-sectional analyses. SETTING. A regional hospital in Hong Kong. PATIENTS. Chinese children assessed between January 2006 and December 2010 at Tseung Kwan O Hospital for being overweight or obese. MAIN OUTCOME MEASURES. The demographics, anthropometric data, acanthosis nigricans status, and biochemical results were analysed. RESULTS. A total of 543 overweight/obese children were studied with 64% being boys and 29% had insulin resistance. Adolescents aged 12 to 18 years, compared with children aged 5 to 11 years, were more likely to have acanthosis nigricans (63% vs 47%; P<0.001) and insulin resistance (37% vs 25%; P=0.005). Compared with overweight children, those who were obese were more likely to have the two conditions: acanthosis nigricans (59% vs 44%; P=0.005) and insulin resistance (35% vs 19%; P=0.001). Compared with those without acanthosis nigricans, those with the condition had significantly higher mean values for systolic blood pressures (P<0.001), 2-hour post-oral glucose tolerance test glucose level (P=0.021), fasting insulin level (P<0.001), homeostasis model of assessment-insulin resistance (P<0.001), fasting triglyceride level (P<0.001), and alanine aminotransferase level (P=0.002), but a lower high-density lipoprotein cholesterol level (P<0.001). Those with acanthosis nigricans were also more likely to have insulin resistance (P<0.001), hypertension (P=0.021), fatty liver (P=0.001), and abnormal glucose homeostasis (P=0.003). CONCLUSION. Obese Chinese children and adolescents with acanthosis nigricans had a higher chance of having insulin resistance and cardiometabolic co-morbidities. Acanthosis nigricans is an important clinical feature warranting early attention and evaluation to facilitate timely interventions and monitoring.

Biological treatment of pharmaceutical wastewater from the antibiotics industry

Pharmaceutical wastewater generated by an antibiotics (penicillin) company was treated by aerobic membrane bioreactors (MBRs) and sequencing batch reactors (SBRs). At a low organic loading rate of 0.22 kg-COD m(-3)d(-1), both types of reactors were capable of treating the wastewater such that the treated effluent met the discharge regulation except for the total dissolved solids. However, when the loading rate was increased to 2.92 kg-COD m(-3)d(-1), foaming issues resulted in unstable performance. Overall, the MBRs achieved better solid removal but the SBRs performed better in regards to the degradation of aromatic compounds, as determined by UV absorbance (UVA). Finally, ozonation was applied on two different streams and showed promise on the strong stream - that corresponds to the formulation effluent and contains most of the biorefractory compounds. Ozonation successfully reduced the UVA, lowered the pH and increased the biochemical oxygen demand : chemical oxygen demand (BOD5 : COD) ratio of the strong stream. However, it was less efficient on the effluent having undergone pre-treatment by a biofilter due to a lack of selectivity towards refractory compounds.

Different types of carbon nanotube-based anodes to improve microbial fuel cell performance

The microbial fuel cell (MFC) is an innovative technology for producing electricity directly from biodegradable organic matter using bacteria. Among all the influenceable factors, anode materials play a crucial role in electricity generation. Recently, carbon nanotubes (CNTs) have exhibited promising properties as electrode material due to their unique structural, and physical and chemical properties. In this study, the impacts of CNT types in CNT-based anodes were investigated to determine their effect on both efficiency of wastewater treatment and power generation. The CNTs, namely single-walled CNT with carboxyl group (SWCNT), multi-walled CNT with carboxyl group (MWCNT-COOH) and multi-walled CNT with hydroxyl group (MWCNT-OH) were used to fabricate CNT-based anodes by a filtration method. Overall, MWCNTs provided better results than SWCNTs, especially in the presence of the -OH groups. The highest power and treatment efficiencies in MFC were achieved with an anode made of MWCNT-OH filtered on Poreflon membrane; the open circuit voltage attained was 0.75 V and the maximum power density averaged 167 mW/m(2), which was 130% higher than that obtained with plain carbon cloth. In addition, MWCNT-OH is more cost-effective, further suggesting its potential to replace plain carbon cloth generally used for the MFC anode.

Suitability of ozone pre-treatment for amoxicillin wastewater

This study deals with the ozonation of amoxicillin in real pharmaceutical wastewater and its efficacy as a pre-treatment, prior to biological degradation by a mixed culture of bacteria in a sequencing batch reactor (SBR). An ozone utilization of 0.27 g/g-COD (chemical oxygen demand) lowered the pH of the wastewater to 6.6, reduced the specific ultraviolet absorption by 43% and increased the biochemical oxygen demand (BOD) concentration by 37%. The BOD:COD ratio became equal to 0.89, making the ozonated wastewater seemingly suitable for biological treatment; however, when the ozonated effluent was fed to the SBR, the reactor performance degraded, an effect which was attributed to ozonation by-products. In conclusion, ozonation might not be a suitable pre-treatment for pharmaceutical wastewater containing amoxicillin, and biotreatment with properly acclimated biomass may be a better option for treatment of such pharmaceutical wastewater.

Doxycycline inhibits matrix metalloproteinase-2 secretion from TSC2-null mouse embryonic fibroblasts and lymphangioleiomyomatosis cells

BACKGROUND AND PURPOSE

Lymphangioleiomyomatosis (LAM) is characterized by the abnormal growth of smooth muscle-like cells (LAM cells) and cystic destruction of the lung parenchyma. LAM cell-derived matrix metalloproteinases (MMPs) are thought to play a prominent role in the tissue destruction. The aim of this study was to determine whether doxycycline, a known MMP inhibitor, can inhibit LAM cell proliferation or mitochondrial function and/or modulate MMPs and their tissue inhibitors (TIMPs).

EXPERIMENTAL APPROACH

Wild-type and tuberous sclerosis complex-2 (TSC2)-null mouse embryonic fibroblasts (MEFs) were cultured in DMEM containing 10% fetal bovine serum (FBS). Human LAM cells were derived from the lungs of LAM patients and airway smooth muscle cells from control subjects. Cells were stimulated with FBS with or without doxycycline for up to 9 days. Proliferation was assessed by manual cell counts and MTT assay, MMP production by zymography and ELISA, and TIMP production using elisa.

KEY RESULTS

Doxycycline did not change FBS-induced proliferation in MEFs or human cells. However, doxycycline did reduce metabolic activity of both wild-type and TSC2-null MEFs and LAM cells, but had no effect on control cells. Furthermore, doxycycline reduced MMP-2 from MEFs and decreased active-MMP-2 from LAM cells but had no effect on TIMP-1 and TIMP-2 from human LAM cells.

CONCLUSIONS AND IMPLICATIONS

Doxycycline decreased MMP levels and cell metabolic activity, which raises the possibility of therapeutic efficacy in LAM.

Multi-walled carbon nanotubes as electrode material for microbial fuel cells

The microbial fuel cell (MFC) is a novel and innovative technology that could allow direct harvesting of energy from wastewater through microbial activity with simultaneous oxidation of organic matter in wastewater. Among all MFC parts, electrode materials play a crucial role in electricity generation. A variety of electrode materials have been used, including plain graphite, carbon paper and carbon cloth. However, these electrode materials generated only limited electricity or power. Recently, many research studies have been conducted on carbon nanotubes (CNTs) because of their unique physical and chemical properties that include high conductivity, high surface area, corrosion resistance, and electrochemical stability. These properties make them extremely attractive for fabricating electrodes and catalyst supports. In this study, CNT-based electrodes had been developed to improve MFC performance in terms of electricity generation and treatment efficiency. Multi-walled carbon nanotubes (MWCNTs) with carboxyl groups have been employed to fabricate electrodes for single-chamber air-cathode MFCs. The quality of the prepared MWCNTs-based electrodes was evaluated by morphology, electrical conductivity and specific surface area using a field emission scanning electron microscope, four-probe method and Brunauer-Emmerr-Teller method, respectively. The performance of MFCs equipped with MWCNT-based electrodes was evaluated by chemical analysis and electrical monitoring and calculation. In addition, the performance of these MFCs, using MWCNTs as electrodes, was compared against that using commercial carbon cloth.

Physico-chemical characterisation versus in situ micro-structural characterisation of membrane fouling in membrane bioreactors

Fouling characteristics of aerobic submerged membrane bioreactors were analysed under two different membrane materials. Polyethersulfone (PES) membranes were found to foul faster at sub-critical flux than polyolefin (PO) membranes. Physico-chemical characterisation, by means of comparison of extracellular polymeric substances (EPS) and soluble microbial products (SMP) concentrations, as well as the mixed liquor suspended solids (MLSS) concentration were unable to explain the differences in membrane fouling of the contrasting membrane materials. The use of confocal laser scanning microscopy (CLSM) to image organic foulants directly on the membrane surface, coupled with image analyses showed that membrane fouling mechanism shifted from a biofilm initiated process on PO membranes to a bio-organic dominated process on PES membranes under sub-critical flux conditions. These results show that physico-chemical characterisation of an MBR process may not effectively distinguish the effectiveness of different membrane materials, so long as operating conditions are identical, and that characterisation of foulants on the membrane surfaces was necessary to elucidate the differences in membrane fouling.

Conception and optimization of a membrane electrode assembly microbial fuel cell (MEA-MFC) for treatment of domestic wastewater

A membrane electrode assembly (MEA) for microbial fuel cells (MEA-MFC) was developed for continuous electricity production while treating domestic wastewater concurrently. It was optimized via three upgraded versions (noted α, β and γ) in terms of design (current collectors, hydrophilic separator nature) and operating conditions (hydraulic retention time, external resistance, aeration rate, recirculation). An overall rise of power by over 100% from version α to γ shows the importance of factors such as the choice of proper construction materials and prevention of short-circuits. A power of 2.5 mW was generated with a hydraulic retention time of 2.3 h when a Selemion proton exchange membrane was used as a hydrophilic separator in the MEA and 2.8 mW were attained with a reverse osmosis membrane. The MFC also showed a competitive value of internal resistance (≈40-50 Ω) as compared to the literature, especially considering its large volume (3 L). However, the operation of our system in a complete loop where the anolyte was allowed to trickle over the cathode (version γ) resulted in system failure.

Self-focused acoustic ejectors for viscous liquids

Self-focused acoustic ejectors using the Fresnel zone plate (FZP) have been developed for ejecting viscous liquids, without nozzle, in the drop-on-demand mode. The FZP is composed of a lead zirconate titanate piezoelectric plate patterned with a series of annular electrodes, with the unelectroded region of the plate removed. Our results show that the acoustic waves are effectively self-focused by constructive interference in glycerin (with a viscosity of 1400 mPa s), giving small focal points with a high pressure. Due to the high attenuation, the wave pressure decreases significantly with the distance from the FZP. Nevertheless, the pressure at the focal points 2.5 and 6.5 mm from the FZP is high enough to eject glycerin droplets in the drop-on-demand mode. Driven by a simple wave train comprising a series of sinusoidal voltages with an amplitude of 35 V, a frequency of 4.28 MHz, and a duration of 2 ms, the ejector can eject fine glycerin droplets with a diameter of 0.4 mm at a repetition frequency of 120 Hz in a downward direction. Droplets of other viscous liquids, such as the prepolymer of an epoxy with a viscosity of 2000 mPa s, can also be ejected in the drop-on-demand mode under similar conditions.

An experimental study on the effect of spacer on concentration polarization in a long channel reverse osmosis membrane cell

This study was to experimentally investigate the performance and organic fouling behaviour in a 1-m long RO membrane channel with or without spacer for desalting. It was found that local permeate flux distributed heterogeneously along the long membrane channel without a spacer inserted due to exponential growth of concentration polarization, which also resulted in decreasing salt rejection and increasing organic fouling along the membrane channel in the downstream direction. This heterogeneity could be lessened by inserting a spacer into the channel, which mitigated concentration polarization due to the enhanced turbulence caused by a spacer, especially at the downstream portion of the channel. However, in the upstream of the channel, inserting a spacer exerted an additional vertical resistance which might counteract the effect of concentration polarization mitigation by a spacer and caused a lower permeate flux. This suggests that it is necessary to consider the integral effect of spacer for designing an RO membrane module and an overall RO system in order to prevent extra resistance, reduce concentration polarization and membrane fouling.

Simultaneous ammonium-nitrogen and copper removal, and copper recovery using nitrifying biofilm from the ultra-compact biofilm reactor

Simultaneous ammonium-nitrogen (NH(4)(+)-N) and copper removal, and copper recovery in synthetic wastewater using nitrifying biofilm from an ultra-compact biofilm reactor (UCBR) was demonstrated in batch studies, which consisted of three phases: Phase 1 for NH(4)(+)-N and copper removals, Phase 2 for copper recovery, and Phase 3 for NH(4)(+)-N removal. The results showed that more than 96.3% of copper was removed within 60min, while 60.1% of the adsorbed copper was recovered through rinsing the biofilms with 0.1mM of ethylenediaminetetraacetic acid (EDTA). The nitrifying biofilm was able to adsorb 0.245mg of copper/g of biofilms. After recovery treatment, 29.4% of copper remained bound within the nitrifying biofilms. No significant inhibitory effects towards NH(4)(+)-N removal in the presence of 0.92mg copper/L was noted in Phase 1 compared with the control test. However, lower initial pH condition in the recovery process and the accumulation of copper on the biofilm led to 50% inhibition on NH(4)(+)-N removal efficiency in the subsequent phase.

Feasibility of submerged anaerobic membrane bioreactor (SAMBR) for treatment of low-strength wastewater

Two 6-L submerged anaerobic membrane bioreactors (SAMBR) with SRT of 30 and 60 d (denoted as R30 and R60, respectively) were set up and operated for five months, with a mixture of glucose as substrate. Feasibility of SAMBR was studied for treatment of low-strength wastewater. First two months were identified as acclimation stage. A COD removal efficiency was achieved stably at around 99% and biogas productions were maintained at 0.023 and 0.028 L CH4/gMLVSSd for R30 and R60, respectively. Even though R60 contained higher MLVSS concentration, no significant difference of treatment performances between both reactors was found due to the low organic loading rate and high purification function of membrane. In the investigation of membrane fouling, less irreversible fouling was observed for R30 compared to R60. High non-flocculent concentration of R60 would be responsible for membrane internal pore blocking and deteriorated effluent quality.

Treatment of RO brine-towards sustainable water reclamation practice

Treatment and disposal of RO brine is an important part in sustaining the water reclamation practice. RO brine generated from water reclamation contains high concentration of organic and inorganic compounds. Cost-effective technologies for treatment of RO brine are still relatively unexplored. Thus, this study aim to determine a feasible treatment process for removal of both organic and inorganic compounds in RO brine generated from NEWater production. The proposed treatment consists of biological activated carbon (BAC) column followed by capacitive deionization (CDI) process for organic and inorganic removals, respectively. Preliminary bench-scale study demonstrated about 20% TOC removal efficiency was achieved using BAC at 40 mins empty bed contact time (EBCT) while the CDI process was able to remove more than 90% conductivity reducing it from 2.19 mS/cm to only about 164 microS/cm. More than 90% cations and anions in the BAC effluent were removed using CDI process. In addition, TOC and TN removals of 78% and 91%, respectively were also attained through this process. About 90% water recovery was achieved. This process shows the potential of increased water recovery in the reclamation process while volume for disposal can be further minimized. Further studies on the sustainable operation and process optimization are ongoing.

Characterisation of biofilm constituents and their effect on membrane filterability in MBRs

Fouling is still one of the main issues in the operation of membrane bioreactors (MBRs). While most attention has been paid to extracellular polymeric substances (EPS) and soluble microbial products (SMP) in the bulk solution, changes in membrane filterability may be more adequately described by the structural characteristic of the fouling layer or biofilm. This study shows that membrane filterability and the rise in TMP is associated to the changes in the biofiom structure, and polysaccharides may be the most significant fraction that affects fouling.

An insight into cathode options for microbial fuel cells

Microbial fuel cell (MFC) is an emerging and promising technology, particularly in the field of wastewater treatment. The MFC capability of achieving organic removal and generating in situ electricity could make it an attractive alternative wastewater treatment technology over conventional treatment technologies. However, MFC is still far from being economically viable, especially because of the cost of the platinum (Pt) catalyst that makes possible the reaction at the cathode. In this study, we tested alternative cathode catalysts, namely sputter-deposited Cobalt (Co) and denitrifying bacteria (biocathode). The performance of these innovative cathodes was compared with that of classic Pt-cathodes. Co competed well with Pt, but further research is still required for biocathodes. However, biocathodes MFC have showed promise.

A microbial fuel cell equipped with a biocathode for organic removal and denitrification

Microbial fuel cells (MFCs) are a promising anaerobic technology but they are limited by the high cost of the catalyst used at the cathode (typically platinum). In this study, we designed a novel type of two-chambered MFC wherein an autoheterotrophic denitrifying biofilm replaced the costly catalyst on the cathode surface. Micro-organisms performed denitrification by using electrons supplied by bacteria oxidizing domestic wastewater and acetate as substrates in the anode chamber. This two-chambered MFC equipped with a biocathode generated during more than 1.5 month up to 9.4 mW m(-2) of anode surface or 0.19 W m(-3) of anode chamber volume, while removing over 65% of COD, 84% of total nitrogen and nearly 30% of suspended solids with domestic wastewater as a substrate, and nearly 95% of acetate in the subsequent experiments.

Hyper-induction of cytokines by avian influenza A (H5N1): The role of signaling pathways and Toll-like receptors (B131)

Avian influenza virus A/HK/483/97 (H5N1) is associated with unusually severe human disease. H5N1 viruses hyper-induce pro-inflammatory cytokines (tumor necrosis factor alpha [TNF-α] and interferon beta [IFN-β]) and macrophage-tropic chemokines from primary human macrophages in vitro and this is paralleled by elevated levels of these cytokines in patients sera. It is therefore important to understand the mechanisms underlying this H5N1 induced differential hyper-induction of cytokines. Unlike H1N1, H5N1 virus strongly activated interferon regulatory factor 3 (IRF3). siRNA mediated gene silencing of IRF3 led to a dramatic reduction of the gene expression of IFN-β in H5N1-infected cells but only a partial decrease in TNF-α gene expression. Thus the differential activation of IRF3 may explain the hyper-induction of IFN-β, but does not fully explain the hyper-induction of TNF-α. Similarly, gene silencing of toll-like receptor 3 (TLR3) did not completely abrogate the TNF-α response. The significance of these findings in the pathogenesis of human H5N1 disease will be discussed.

Evaluation of a long-term operation of a submerged nanofiltration membrane bioreactor (NF MBR) for advanced wastewater treatment

Nanofiltration (NF) is considered as one of the most promising separation technologies to obtain a very good-quality permeate in water and wastewater treatment. A submerged NF membrane bioreactor (NF MBR) using polyamide membranes was tested for a long-term operation and the performance of the NF MBR was compared with that of a microfiltration MBR (MF MBR). Total organic carbon (TOC) concentration in the permeate of the NF MBR ranged from 0.5 to 2.0 mg/L, whereas that of the MF MBR showed an average of 5 mg/L. This could be explained by the tightness of the NF membrane. Although the concentration of organic matter in the supernatant of the NF MBR was higher than that in the permeate due to high rejection by the NF membrane, the NF MBR showed excellent treatment efficiency and satisfactory operational stability for a long-term operation.

Effects of solid retention time on the performance of submerged anoxic/oxic membrane bioreactor

In this study, four similar bench-scale submerged Anoxic/Oxic Membrane Bioreactors (MBR) were used simultaneously to investigate the effects of solids retention time (SRT) on organic and nitrogen removal in MBR for treating domestic wastewater. COD removal efficiencies in all reactors were consistently above 94% under steady state conditions. Complete conversion of NH(4+)-N to NO(3-)-N was readily achieved over a feed NH(4+)-N concentration range of 30 to 50 mg/L. It was also observed that SRT did not significantly affect the nitrification in the MBR systems investigated. The average denitrification efficiencies for the 3, 5, 10 and 20 days SRT operations were 43.9, 32.6, 47.5 and 66.5%, respectively. In general, the average effluent nitrogen concentrations, which were mainly nitrate, were about 22.2, 27.6, 21.7 and 13.9 mg/L for the 3, 5, 10 and 20 days SRT systems, respectively. The rate of membrane fouling at 3 days SRT operation was more rapid than that observed at 5 days SRT. No fouling was noted in the 10 days and 20 days SRT systems during the entire period of study.

Effect of long-term conventional tillage and no-tillage systems on soil and water quality at the field scale

No-tillage (NT) is becoming increasingly attractive to farmers because it clearly reduces soil erosion and production costs relative to conventional tillage (CT). However, the impacts of no-tillage on the quantity and quality of tile drainage water are less well known. Accordingly, two adjacent field scale on-farm CT and NT sites were established to compare the impacts of the two tillage systems on tile drainage and NO3-N loss in tile drainage water. The effect of the two tillage systems on soil structure, hydraulic conductivity, and earthworm population were also investigated. The total NO3-N loss in tile drainage water over the 5-yr period (1995-1999) was 82.3 kg N ha(-1) for the long-term NT site and 63.7 kg N ha(-1) for the long-term CT site. The long-term NT site had 48% more tile drainage (6,975 kL ha(-1)) than the long-term CT site (4,716 kL ha(-1)). The average flow weighted mean (FWM) NO3-N concentration in tile drainage water over the 5-yr period was 11.8 mg N L(-1) for the NT site and 13.5 mg N L(-1) for the CT site. For both tillage systems, approximately 80% of tile drainage and NO3-N loss in tile drainage water occurred during the November to April non-growing season. Long-term NT improved wet aggregate stability, increased near-surface hydraulic conductivity and increased both the number and mass of earthworms relative to long-term CT. The greater tile drainage and NO3-N loss under NT were attributed to an increase in continuous soil macropores, as implied by greater hydraulic conductivity and greater numbers of earthworms.

Tillage, intercrop, and controlled drainage-subirrigation influence atrazine, metribuzin, and metolachlor loss

Atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine) and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] have been found with increasing occurrence in rivers and streams. Their continued use will require changes in agricultural practices. We compared water quality from four crop-tillage treatments: (i) conventional moldboard plow (MB), (ii) MB with ryegrass (Lolium multiflorum Lam.) intercrop (IC), (iii) soil saver (SS), and (iv) SS + IC; and two drainage control treatments, drained (D) and controlled drainage-subirrigation (CDS). Atrazine (1.1 kg a.i. ha-1), metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazine-5(4H)-one] (0.5 kg a.i. ha-1), and metolachlor (1.68 kg a.i. ha-1) were applied preemergence in a band over seeded corn (Zea mays L.) rows. Herbicide concentration and losses were monitored from 1992 to spring 1995. Annual herbicide losses ranged from < 0.3 to 2.7% of application. Crop-tillage treatment influenced herbicide loss in 1992 but not in 1993 or 1994, whereas CDS affected partitioning of losses in most years. In 1992, SS + IC reduced herbicide loss in tile drains and surface runoff by 46 to 49% compared with MB. The intercrop reduced surface runoff, which reduced herbicide transport. Controlled drainage-subirrigation increased herbicide loss in surface runoff but decreased loss through tile drainage so that total herbicide loss did not differ between drainage treatments. Desethyl atrazine [6-chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine] comprised 7 to 39% of the total triazine loss.

Testicular sperm extraction and intracytoplasmic sperm injection in non-obstructive azoospermia

OBJECTIVE

To report the experience in sperm extraction from testicular biopsies (TESE) performed from March 1996 to July 1998 in men with non-obstructive azoospermia (NOA).

METHODS

Comparisons of age, volume of both testes, serum FSH and testosterone in men, and histology of testicular samples in the first cycles between cycles with spermatozoa found and those without spermatozoa found were performed. Comparisons of fertilization, cleavage and pregnancy rates between cycles with spermatozoa injected and those with spermatids injected were performed.

RESULTS

Spermatozoa were found in only 12 out of 26 first TESE cycles (46.2%) and other cycles had spermatids (round cells) only. Age of men, history of mumps orchitis/oligozoospermia, volume of both testes and serum FSH/testosterone levels in men were not significantly different between cycles with and without spermatozoa. The fertilization rate was significantly higher in cycles with spermatozoa injected than those with round cell injections (63.3% vs 23.2%, P < 0.0001, Chi-squared test). The pregnancy rate was 14.3% per cycle when spermatozoa were injected.

CONCLUSIONS

TESE followed by intracytoplasmic sperm injection (ICSI) is an effective treatment in patients with NOA. Less than half of the patients undergoing TESE had spermatozoa recovered. Age of men, volume of both testes and serum FSH/testosterone levels in men were not useful in predicting successful recovery. Compared to using ejaculated and epididymal spermatozoa, fertilization and pregnancy rates were achieved when testicular spermatozoa were used for ICSI.

Comparison of two colloidal silica-based sperm separation media with a non-silica-based medium

OBJECTIVE

To study and compare the effects of three sperm separation media, two silica-based (Percoll; Pharmacia Biotech AB, Uppsala, Sweden, and Isolate; Irvine Scientific, Santa Ana, CA) and one non-silica-based (Ixaprep; Medicult, Copenhagen, Denmark), on the recovery of progressive motile sperm, the percentage of sperm with normal morphology, various sperm motion characteristics determined by computer-aided sperm analysis, and the percentage of acrosome-reacted sperm.

DESIGN

Prospective study.

SETTING

A university-based assisted reproductive technology center.

PATIENT(S)

Male partners of couples attending our infertility clinic.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Various semen parameters.

RESULT(S)

Both Isolate and Ixaprep resulted in enhanced recovery of motile spermatozoa compared with Percoll. The percentage of sperm with forward progressive motility, the percentage of sperm with normal morphology, and various sperm motion characteristics were similar after the use of Percoll and Isolate and were significantly better than after the use of Ixaprep. The same percentage of acrosome-reacted spermatozoa was observed with all three media. Similar results were observed in both normal and subnormal semen samples.

CONCLUSION(S)

The use of Isolate and Ixaprep resulted in better recovery of motile spermatozoa. Other semen parameters were similar with the use of Isolate and Percoll, whereas the use of Ixaprep was associated with lower sperm velocities and fewer morphologically normal spermatozoa.

Assisted reproduction technology in Queen Mary Hospital: ten years' experience

PURPOSE

To review the experience of an assisted reproduction program.

DATA SOURCES

Department of Obstetrics and Gynaecology, University of Hong Kong.

STUDY SELECTION

Assisted reproduction in a tertiary referral centre.

DATA EXTRACTION

Results of assisted reproduction from 1986-1996.

RESULTS

In the past ten years, 1561 treatment cycles of in vitro fertilization and embryo transfer (IVF), 257 of gamete intrafallopian transfer (GIFT) and 217 of pronuclear stage tubal transfer (PROST) were initiated. The clinical pregnancy rates per cycle started were 10.8% for IVF, 16.3% for GIFT and 15.7% for PROST. As a result of improvement in ovarian stimulation and embryo culture, the success rate of the program increased in recent years. The pregnancy rate of IVF per embryo transfer was 20.2% in 1995. Embryo cryopreservation program was started in 1992. Since then, 664 cycles of replacement of frozen-thawed embryos were completed with a pregnancy rate of 14.6% per cycle. One hundred and forty-three cycles of assisted fertilization using various techniques, namely partial zona dissection, subzonal sperm injection and intracytoplasmic sperm injection, were performed. The success rate was the highest for the latter technique with a pregnancy rate of 14% per transfer cycle. A prospective randomized control trial on the use of coculture in assisted reproduction had also been done. Results indicated that coculture of embryos with human oviductal cells improved the implantation rate of the embryos.

CONCLUSION

Various technique development have been made to improve the success rate of assisted reproduction as well as the quality of treatment of infertility.