Effective recycling of disposable medical face masks for sustainable green concrete via a new fiber hybridization technique

Global public response to the COVID-19 (SARS-CoV-2) pandemic is highly focused on human health. However, conservationists have cautioned of unprecedented threats to the natural environment from a new type of non-biodegradable microplastic waste resulting from extensive use of disposable medical face masks (DMFMs). Thus, this waste must be recycled in an eco-friendly manner on an urgent basis. In this research, we developed a new environmentally friendly recycling technique using waste DMFMs in sustainable green concrete. More explicitly, a new fiber hybridization approach has been introduced in which two types of fibers namely DMFM fiber and basalt fiber (BF) were incorporated into fiber reinforced recycled aggregate concrete (FRAC). The volume fractions of DMFM fiber were 0%, 0.1%, and 0.2% and the volume fractions of BF were 0%, 0.25%, and 0.5%. In addition, two mineral admixtures (fly ash and ground granulated blast furnace slag) were also used. Test results indicated increase of approximately 12% in compressive strength, 26% in split tensile strength, and 60% in flexural strength of FRAC containing hybrid fibers and mineral admixtures. The density and ultra-sonic pulse velocity (UPV) of DMFM fiber- and BF-modified FRAC ranged from 2406-2433 kg/m³ and 4502-4541 m/s, respectively, which meets structural concrete requirements. The water absorption rate gradually increased with an increase in the volume fractions of fibers but remained within the allowable water absorption limit for construction materials. Lastly, the microstructure investigation indicated excellent concrete quality, improved interfacial transition zones (ITZs), and good compatibility of host concrete matrix with both DMFM fiber and BF that correlates well with the experimental results reported in this study.

Edible Bird Nest Protects the Kidney From Gentamicin Induced Acute Tubular Necrosis

Every year, there are about 13.3 million cases of acute kidney injury (AKI). Although AKI is a preventable and treatable disease, if left untreated, it has high risk of multiple organ failure and progression to end stage kidney disease. Acute tubular necrosis (ATN) has been recognised as one of the major causes of AKI. Till to date, there is no effective supplement or medication in treating or reversing AKI. Most of the treatment strategies involve preventative measure to minimise the occurrence of AKI or to reverse the cause of AKI. Hence one of the primary area of research interests is to explore the potential treatment for AKI. Edible bird nests (EBN) are edible food produce by the swiftlet’s saliva, which is rich in sialic acids. Sialic acids are monosaccharides that play a vital role in maintaining the integrity and proper function of the human organs, including kidneys. EBN also contains epidermal growth factor, which is widely believed to have rejuvenation and tissue repairing properties. We initiate this study to study the potential reno-protective effect of edible bird’s nests by studying the Wistar rat model of gentamicin-induced AKI. Besides renal profiles, renal histology was also semiquantitatively assessed. In our study, pre-treatment with EBN prevented and ameliorated the gentamicin-induced AKI. To a lesser extent, post-treatment with EBN also protected the kidney from the toxic effect of gentamicin. Our findings are highly indicative that EBN possesses reno-protective properties.

A gravity-driven sintering method to fabricate geometrically complex compact piezoceramics

Highly compact and geometrically complex piezoceramics are required by a variety of electromechanical devices owing to their outstanding piezoelectricity, mechanical stability and extended application scenarios. 3D printing is currently the mainstream technology for fabricating geometrically complex piezoceramic components. However, it is hard to print piezoceramics in a curve shape while also keeping its compactness due to restrictions on the ceramic loading and the viscosity of feedstocks. Here, we report a gravity-driven sintering (GDS) process to directly fabricate curved and compact piezoceramics by exploiting gravitational force and high-temperature viscous behavior of sintering ceramic specimens. The sintered lead zirconate titanate (PZT) ceramics possess curve geometries that can be facilely tuned via the initial mechanical boundary design, and exhibit high piezoelectric properties comparable to those of conventional-sintered compact PZT (d33 = 595 pC/N). In contrast to 3D printing technology, our GDS process is suitable for scale-up production and low-cost production of piezoceramics with diverse curved surfaces. Our GDS strategy is an universal and facile route to fabricate curved piezoceramics and other functional ceramics with no compromise of their functionalities.

Comparison of two different optical coherence tomography angiography devices in detecting healthy versus glaucomatous eyes - an observational cross-sectional study

Background

To understand the differences between two different optical coherence tomography angiography (OCTA) devices in detecting glaucomatous from healthy eyes by comparing their vascular parameters, diagnostic accuracy and test-retest reliability.

Methods

A cross-sectional observational study was performed on healthy and glaucoma subjects, on whom two sets of OCTA images of optic disc and macula were acquired using both AngioVue (Optovue, USA) and Swept Source (Topcon, Japan) OCTA devices during one visit. A novel in-house software was used to calculate the vessel densities. Diagnostic accuracy of the machines in differentiating healthy versus glaucomatous eyes was determined using area under the receiver operating characteristic curve (AUROC) and test-retest repeatability of the machines was also evaluated.

Results

A total of 80 healthy and 38 glaucomatous eyes were evaluated. Glaucomatous eyes had reduced mean vessel density compared to healthy controls in all segmented layers of the optic disc and macula using AngioVue (p ≤ 0.001). However, glaucomatous eyes had higher mean vessel density on optic disc scans using Swept Source, with lack of statistically significant difference between healthy and glaucomatous eyes. The AUROC showed better diagnostic accuracy of AngioVue (0.761–1.000) compared to Swept Source (0.113–0.644). The test-retest reliability indices were generally better using AngioVue than Swept Source.

Conclusions

AngioVue showed better diagnostic capability and test-retest reliability compared to Swept Source. Further studies need to be undertaken to evaluate if there is any significant difference between the various machines in diagnosing and monitoring glaucoma.

P204 Automated detection of atrial fibrillation based on stationary wavelet transform and artificial neural network targeted for embedded system-on-chip technology

Conclusion

The proposed AF detection algorithm based on combination of SWT and ANN can achieve high accuracy and is suitable to be implemented as a standalone AF classifier based on embedded SoC technology targeted for early detection of AF in the community.

Assessment of Quality of Life and Safety in Postmenopausal Breast Cancer Patients Receiving Letrozole as an Early Adjuvant Treatment

Purpose

There are few reports from Asian countries about the long-term results of aromatase inhibitor adjuvant treatment for breast cancer. This observational study aimed to evaluate the long-term effects of letrozole in postmenopausal Korean women with operable breast cancer.

Methods

Self-reported quality of life (QoL) scores were serially assessed for 3 years during adjuvant letrozole treatment using the Korean version of the Functional Assessment of Cancer Therapy-Breast questionnaires (version 3). Changes in bone mineral density (BMD) and serum cholesterol levels were also examined.

Results

All 897 patients received the documented informed consent form and completed a baseline questionnaire before treatment. Adjuvant chemotherapy was administered to 684 (76.3%) subjects, and 410 (45.7%) and 396 (44.1%) patients had stage I and II breast cancer, respectively. Each patient completed questionnaires at 3, 6, 12, 18, 24, 30, and 36 months after enrollment. Of 897 patients, 749 (83.5%) completed the study. The dropout rate was 16.5%. The serial trial outcome index, the sum of the physical and functional well-being subscales, increased gradually and significantly from baseline during letrozole treatment (p<0.001). The mean serum cholesterol level increased significantly from 199 to 205 after 36 months (p=0.042). The mean BMD significantly decreased from −0.39 at baseline to −0.87 after 36 months (p<0.001).

Conclusion

QoL gradually improved during letrozole treatment. BMD and serum cholesterol level changes were similar to those in Western countries, indicating that adjuvant letrozole treatment is well tolerated in Korean women, with minimal ethnic variation.

Triazolium cyclodextrin click cluster-resin conjugate: an enrichment material for phosphatidylinositol (3,4,5)-triphosphate

UltraLink was functionalized with a triazolium cyclodextrin click cluster (CCC) which provides a well-oriented, multivalent, positively charged binding site for PtdIns(3,4,5)P₃. MALDI TOF MS and LC ESI MS/MS MRM analysis of spiked PtdIns(3,4,5)P₃ in lipid extract suggest that triazolium CCC-UltraLink conjugate can be used as an enrichment material for PtdIns(3,4,5)P₃.

Broadband signal response of thermo-acoustic devices and its applications

Thermo-acoustic (TA) transducers are generation of sound speakers without any mechanical vibration system which exhibit an extremely wide frequency response range. In this paper, acoustic field responses to broadband input signals applied to both free-standing and nano-thinfilm-substrate thermo-acoustic devices are developed theoretically by using the Fourier transformation. A series of signals, including single-frequency signal, square root signal, periodic triangle wave signal, and periodic rectangular pulse signal, are applied to these TA devices in simulations and the acoustic pressure responses are investigated. The reproducibility of input signals is predicted. The single frequency results show good agreement with previously published experimental results. Alternative methods for reproducing the original signals with small distortion and low power consumption are introduced. The excellent performance of the TA devices on broadband signal responses will provide a design approach for sound parametric array and underwater communication equipment.

Efficacy of the APACHE II score at ICU discharge in predicting post-ICU mortality and ICU readmission in critically ill surgical patients

In this study, we evaluated the efficacy of the discharge Acute Physiology and Chronic Health Evaluation (APACHE) II score in predicting post-intensive care unit (ICU) mortality and ICU readmission during the same hospitalisation in a surgical ICU. Of 1190 patients who were admitted to the ICU and stayed >48 hours between October 2007 and March 2010, 23 (1.9%) died and 86 (7.2%) were readmitted after initial ICU discharge, with 26 (3.0%) admitted within 48 hours. The area under the receiver operating characteristics curve of the discharge and admission APACHE II scores in predicting in-hospital mortality was 0.631 (95% confidence interval [CI] 0.603 to 0.658) and 0.669 (95% CI 0.642 to 0.696), respectively (P=0.510). The area under the receiver operating characteristics curve of discharge and admission APACHE II scores for predicting all forms of readmission was 0.606 (95% CI 0.578 to 0.634) and 0.574 (95% CI 0.545 to 0.602), respectively (P=0.316). The area under the receiver operating characteristics curve of discharge APACHE II score in predicting early ICU readmissions was, however, higher than that of admission APACHE II score (0.688 [95% CI 0.660 to 0.714] versus 0.505 [95% CI 0.476 to 0.534], P=0.001). The discharge APACHE II score (odds ratio [OR] 1.1, 95% CI 1.01 to 1.22, P=0.024), unplanned ICU readmission (OR 20.0, 95% CI 7.6 to 53.1, P=0.001), eosinopenia at ICU discharge (OR 6.0, 95% CI 1.34 to 26.9, P=0.019), and hospital length-of-stay before ICU admission (OR 1.02, 95% CI 1.01 to 1.03, P=0.021) were significant independent factors in predicting post-ICU mortality. This study suggests that the discharge APACHE II score may be useful in predicting post-ICU mortality and is superior to the admission APACHE II score in predicting early ICU readmission in surgical ICU patients.

Coarctation of the aorta: nonsurgical treatment using stent implantation

INTRODUCTION

Coarctation of the aorta (CoA) accounts for 5%-8% of all congenital heart defects. If left untreated, most patients with significant CoA will have varying degrees of morbidity (e.g. hypertension, stroke, collateral formation and ventricular hypertrophy), possibly even mortality. Traditionally, treatment for this condition is surgical. Herein, we report stenting during catheterisation as an alternative nonsurgical treatment option for patients with CoA, and present the treatment outcomes of patients who underwent this treatment option.

METHODS

We retrospectively reviewed four patients (2 men and 2 women; age range 20-41 years) who underwent CoA stenting under general anaesthesia for the treatment of native CoA or restenosis of CoA at our institution. Three patients had a 40-mm Palmaz stent inserted, while one had a 39-mm Cheatham-Platinum covered stent inserted. Angiography and measurement of pressure gradients were performed before and after stent implantation to ensure good treatment outcomes.

RESULTS

The patients' treatment outcomes were good, with a significant reduction in pressure gradients across the narrowed segments. Angiography showed relief of CoA. The patients were followed up for 1-3 years, during which no complications were noted.

CONCLUSION

This is the first reported series in Singapore on the nonsurgical treatment of CoAs in adult patients using stents during interventional cardiac catheterisation. This less invasive procedure may lead to a new paradigm shift with regard to the treatment of CoA.

P2-16-14: Skin Sparing Mastectomy and Immediate Latissimus Dorsi Flap Reconstruction: Patient Reported Outcome and Factors Affecting the Highest Patient Satisfaction

Background: Skin sparing mastectomy (SSM) and immediate breast reconstruction (IBR) with latissimus dorsi (LD) flap is a tailored surgical procedure for breast cancer patients. In this study the oncologic safety, morbidities, and aesthetic results of SSM and LD IBR, as regards to patient satisfaction, were assessed.

Material and Methods: Between March 2000 and February 2011, single surgeon performed SSM and IBR for 145 patients. Eighty-five patients completed the patient satisfaction survey, and 65 patients with SSM and LD IBR were included. The patients were divided into 2 groups according to their degree of satisfaction, and a stratified analysis was performed.

Results: The mean age of the patients was 48.4 years (range, 21–74), and the pathologic results were infiltrating ductal carcinoma (n=48, 73.8%), ductal carcinoma in situ (n=15, 23.1%), and others (n=2, 3.1%). After a mean follow-up of 34 months (range, 1.6−89.9) no local recurrence occurred, and there were no skin necrosis or LD flap loss. Donor site morbidities were seroma (n=8, 12.3%), scarring (n=8, 12.3%), and back pain (n=6, 9.2%).

An intelligent tutoring system for trauma management (Trauma-Teach): a preliminary report

Trauma-Teach is an interactive software for tutoring surgical trainees on medical trauma management procedures. Users of the system interact with a virtual patient suffering from trauma injuries. The task of the user is to stabilise the virtual patient, discover the underlying injuries and decide on an appropriate management plan. Artificial intelligence techniques are used to simulate the patient's pulmonary and cardiovascular systems in real time, determine the responses and results of treatments and diagnostics accordingly, model the patient deterioration if wrong actions are taken, and give a measure of reality to the system by selecting actual trauma cases from the hospital's database.

Brucella abortus infection in indigenous Korean dogs

Three dogs reared on a dairy farm with a high incidence for Brucella abortus were serologically positive for B. abortus and no other Brucella spp. The identity of the organism was confirmed to be B. abortus by AMOS (abortus melitensis ovis suis)-polymerase chain reaction with specific primers for B. canis. One hundred percent homology of the canine isolate and the bovine pathogen isolated from the farm was demonstrated. The only possible source of infection was infected cattle on the same farm. It is suggested that dogs be routinely included in brucellosis surveillance and eradication programs.

Self-organized superlattice formation during crystal growth from continuous beam fluxes

Alloy superlattice structures consisting of alternating Si-rich and C-rich layers form spontaneously during gas-source molecular beam epitaxy of Si(1-y)C(y) on Si(001) from constant Si2H6 and CH3SiH3 precursor fluxes at T(s)=725-750 degrees C. The self-organized patterning is due to a complex interaction among competing surface reactions. During growth of the initial Si-rich layer, strain-driven C segregation to the subsurface results in charge transfer from surface Si atom dangling bonds to C backbonds. This decreases the Si2H6 sticking probability, and, hence, the instantaneous deposition rate, thereby enhancing C segregation. The Si-rich layer continues until a critical C coverage is reached allowing nucleation of a C-rich layer which grows until the excess subsurface C is depleted. The process then repeats with periods tunable through the choice of T(s) and y(avg).

Characterization of the protective response against a homologous challenge infection with Strongyloides venezuelensis in rats

The protective response in rats against a homologous challenge infection with Strongyloides venezuelensis was characterized. In an initial infection with 1000 filariform larvae and migrating larvae (L(3)) of S. venezuelensis, the population of L(3) in the lungs on day 3 postinfection (PI), and that of adult worms in the small intestine on day 7 PI, were 180.8+/-14.5 and 336.8+/-70.7, respectively. The latter were gradually expelled towards day 42 PI. After the initial infection, the rats developed strong immunity against a homologous challenge infection as manifested by a marked reduction in worm populations, stunted body length and width, damage to reproductive organs, impaired egg production and rapid expulsion of the worms by day 14 after challenge. Expulsion of the worms was preceded by a significantly elevated (P<0.05) peripheral blood eosinophil (PBE) count, both in the initial (200.0+/-26.5 x 10(3)ml) and the challenge infection (400.9+/-165.4 x 10(3)ml). These findings suggest that rats acquire strong homologous immunity following initial exposure to S. venezuelensis. It is suggested that PBEs are involved in worm expulsion. A major target of these effector mechanisms is the reproductive system of S. venezuelensis.

The prevalence and pattern of contact lens use in a Singapore community

PURPOSE

We conducted a cross-sectional survey to determine the prevalence, socio-demographic patterns, and characteristics of contact lens use in an electoral community in Singapore.

METHODS

One thousand eight hundred fifteen persons aged between 12-55 years from 768 households were surveyed using a standardized pre-tested questionnaire.

RESULTS

The percentage of contact lens wearers in the survey populations was 9.0%. Forty-two percent of surveyed individuals were myopes, 21.8% of whom wore contact lenses. Contact lens wearers tended to be young Chinese females with higher level education and incomes. Most wore monthly disposable or daily wear soft contact lenses. Convenience and cosmesis were the main reasons cited for contact lens wear. Optometrists, who prescribed the bulk of contact lenses, were also the most influential in determining consumers' choice of lenses.

CONCLUSION

Information gathered in this population-based survey may be used to facilitate national eye-care planning and provide a baseline for comparison with rates of lens wear found in other countries and in future surveys.

Theoretical analysis of the effect of cutaneous metabolism on skin permeation of parabens based on a two-layer skin diffusion/metabolism model

The effect of cutaneous metabolism on the skin penetration of drugs was analyzed based on a two-layer skin diffusion/metabolism model. In vitro permeation studies of propylparaben and butylparaben with or without an esterase inhibitor, diisopropyl fluorophosphate (DFP), were performed. Pretreatment of the skin with DFP prolonged the lag time for the penetration of intact parabens. Additionally, DFP significantly decreased the total flux of butylparaben, but not that of propylparaben. Model analysis of the penetration profiles revealed that DFP inhibits the cutaneous metabolism without affecting any other processes. To comprehensively understand the relationships among lipophilicity, metabolic rate, and skin permeation of drugs, simulation studies were performed with newly derived equations concerning the permeability coefficient and the lag time for the penetration of both intact and metabolite forms. The analysis revealed that the lag time for the penetration of both intact and metabolite forms becomes shorter with increasing metabolic rate. As the metabolic rate of the drug increases, skin penetration of the intact form decreases whereas that of the metabolite increases. The total flux of intact and metabolite forms increases with increasing metabolic rate, being more obvious for highly lipophilic drugs. This indicates that the permeation of lipophilic compounds such as butylparaben is more highly affected by cutaneous metabolism in the viable layer because these compounds easily penetrate the stratum corneum layer. Consequently, the balance between the permeability of drug across the stratum corneum and the dermis has been implicated to impose a significant influence on the percutaneous absorption of drugs subjected to cutaneous metabolism.

Adaptive approximation bounds for vertex based contour encoding

When approximating the shape of a region, a fixed bound on the tolerable distortion is set for approximating its contour points. An adaptive approximation bound for lossy coding of the contour points is proposed. A function representing the relative significance of the contour points is defined to adjust the distortion bound along the region contour allowing an adaptive approximation of the region shape. The effectiveness of the adaptive contour coding approach for a region-based coding system is verified through experiments.

Intravenous fumonisin B1 induces cell proliferation and apoptosis in the rat

In the rat, the target organs of fumonisin B1, a mycotoxin produced by Fusarium moniliforme, are the kidney and liver. Fumonisin B1 is also hepatocarcinogenic in the rat and is associated epidemiologically with esophageal cancer in humans. We investigated the effect of a single intravenous dose of fumonisin B1 on cell proliferation, lesion development, and glutathione status in the major target organs of the rat. Male Sprague-Dawley rats were injected intravenously with fumonisin B1 at 0 or 1.25 mg/kg and were euthanized at 12 hr or, 1,2,3, or 5 days. An intraperitoneal injection of 5-bromo-2'-deoxyuridine at 100 mg/kg was given 90 min prior to euthanasia. In fumonisin B1 treated rats, serum cholesterol and serum urea nitrogen were elevated; however, the activity of hepatic enzymes was unaffected. Hepatic and renal glutathione concentrations were depressed at 12 and 24 hr, respectively, with subsequent recovery. Histologic changes were most prominent in the outer medulla of the kidney, with cell proliferation and apoptosis followed by nephrosis. Cell proliferation also occurred in the liver and esophagus, but in the absence of tissue injury. The labeling index peaked on day 1 for the liver and on day 3 for the esophagus. These results confirm that the primary target organ of fumonisin B1 in the rat is the kidney and support the concept that fumonisin B1-induced mitogenesis may be the mechanism of carcinogenesis.

A method for the separation of delta bilirubin using Cibacron Blue affinity chromatography

We developed and evaluated a method for the separation of delta bilirubin (B delta) by micro-column affinity chromatography based on Cibacron Blue 3G-A-Agarose. Untreated serum was applied to affinity columns and free non-protein bound bilirubins were eluted with phosphate buffer containing 20 g/l Triton X-100. Retained albumin was eluted using caffeine-benzoate reagent and bilirubin associated with this fraction (B delta) quantitated by the method of Jendrassik and Gróf modified by Doumas et al (Clin Chem 1985;31:1779-1789); results correlated well with the high performance liquid chromatography (HPLC) method (n = 35, y (affinity) = 1.009x (HPLC)-5.49; r = 0.959) described by Lauff et al. (J Chromatography 1981;226:391-402). Two controls analyzed with each batch gave between-batch imprecision less than 4.0% (n = 10; Control 1, mean = 20.05 mumol/l; Control 2, mean = 74.82 mumol/l). Within-batch imprecision was less than 3.3% for both levels. Specimens collected from 25 neonates less than 20 days of age showed a B delta concentration of 1.7 +/- 0.7 mumol/l (mean +/- 1 S.D.) and percent B delta of 2.2 +/- 1.9 (mean total bilirubin +/- 1 S.D. = 118 +/- 79 mumol/l). Although time consuming, this simple and precise method allows the measurement of B delta in laboratories without the need for specialized instruments.

The prognostic significance of urinary albumin in Polynesians with non-insulin-dependent diabetes

Polynesian (59 Maori and 30 Pacific Island) patients were identified from two diabetes clinic registers and followed for a mean of 4.8 years, in order to determine the prognostic significance of urinary albumin excretion. Events were defined as death or entry onto a renal replacement programme. Fourteen events occurred during the period of follow-up. Urinary albumin/creatinine ratio was treated as a continuous variable in a proportional hazards analysis. A 10-fold increase in albumin/creatinine ratio was associated with a 5-fold increase in the risk of an event (95% C.I. = 2.05-12.09). In conclusion, elevated urinary albumin/creatinine predicted mortality and renal morbidity in Maori and Pacific Island patients with non-insulin-dependent diabetes.

Bradyarrhythmias in acute myocardial infarction: should thrombolysis lower the decision threshold for temporary pacing?

Both acute myocardial infarction and reperfusion therapy with thrombolytic agents may be associated with bradyarrhythmias, and there may be a case for 'prophylactic' insertion of a temporary pacing wire in selected patients. We describe 4 patients in whom clinical decisions had to be made concerning the appropriateness and timing of temporary pacing, and discuss the implications for modern guidelines on the indications for pacing in such a setting.

Clinical and ethnic characteristics associated with urinary albumin excretion in noninsulin dependent diabetic subjects attending the Wellington Hospital diabetes clinic

In noninsulin dependent diabetes, elevation of urinary albumin excretion above the normal range is thought to predict increased mortality. A random urinary albumin/creatinine ratio and the following clinical characteristics were recorded on 405 patients with noninsulin dependent diabetes attending the Wellington Hospital diabetes clinic; (1) ethnic origin, (2) age, (3) sex, (4) age at diagnosis, (5) duration since diagnosis of diabetes, (6) body mass index, (7) systolic blood pressure, (8) diastolic blood pressure, (9) retinopathy, (10) insulin therapy, (11) antihypertensive therapy, and (12) the presence or absence of treated cardiovascular disease. The overall prevalence of elevated urinary albumin/creatinine ratio (greater than 2.2 mg/mmol) was 45%. Stepwise regression analysis showed that 12% of the variability of urinary albumin/creatinine ratio in our clinic population could be accounted for by ethnic origin of patients, with noncaucasians (the Maori, Pacific Islanders and Asians) having a higher urinary albumin excretion than caucasians (p less than 0.001). Systolic blood pressure, retinopathy and cardiovascular disease predicted a further 8% of this variability. The cause of this ethnic difference in urinary albumin excretion and its possible relationship to excess mortality in noncaucasians is not yet known.

Effects of low and high relative molecular protein mass on four methods for total protein determination in urine

Four commonly used methods for the determination of total protein in urine were compared. These were two biuret methods using different precipitants, a Ponceau S method and a Coomassie Brilliant Blue method. The protein content of the urines was also evaluated by sodium dodecylsulphate polyacrylamide gel electrophoresis. The biuret method with ethanolic phosphotungstic acid as precipitant correlated best with the Coomassie Brilliant Blue method (r = 0.944; p less than 0.001) but less well with the Ponceau S (r = 0.895; p less than 0.001) or biuret-trichloroacetic acid (r = 0.874; p less than 0.001) methods. For urines with normal electrophoretic protein patterns, the imprecise biuret-trichloroacetic acid method (cv = 18.5%) gave the greatest number of false high results (23 in 36 urines) as assessed by electrophoresis. False low results were common in low relative molecular mass (Mr) proteinuria, especially with the biuret-tricholoroacetic acid and Ponceau S methods. High Mr proteinuria rarely caused false low results. Discrepancies between methods appear to have resulted from incomplete precipitation of low Mr protein by trichloroacetic acid.

Comparison of urinary albumin excretion between Maoris, Pacific Island Polynesians and Europeans with non-insulin-dependent diabetes

Elevated urinary albumin excretion is a marker for increased mortality and morbidity in European subjects with non-insulin-dependent diabetes. Urinary albumin excretion was compared in 32 Maoris, 34 Pacific Island Polynesians and 66 subjects of European origin with non-insulin-dependent diabetes attending a diabetes clinic in Wellington, New Zealand. The random urinary albumin to creatinine ratio was used as an estimation of urinary albumin excretion rate. The random urinary albumin to creatinine ratio was significantly higher in Maori and Pacific Island Polynesian subjects, compared to diabetic Europeans (geometric mean urinary albumin to creatinine ratios were 13.13, 12.00 and 2.79 mg/mmol respectively, P less than 0.05). These findings would be consistent with the high mortality and morbidity seen in the Maori and Pacific Island Polynesian diabetic populations. The correlation between hypertension and increased urinary albumin excretion was stronger in the Europeans than in the Maoris and Pacific Island Polynesians studied, suggesting that differences in blood pressure alone are unlikely to account for the observed differences in albumin excretion. Follow-up studies are required to determine whether diabetic Maoris and Pacific Island Polynesians with increased urinary albumin excretion have a similar prognosis to their European counterparts.

Effects of sodium dodecylsulphate, dye concentration and paraprotein on coomassie blue dye-binding assays for protein in urine

Various Coomassie Blue reagents, containing either increased dye concentration or added sodium dodecylsulphate, were compared with a biuret method for the assay of total protein in urine. When immunoglobulin free light chain protein or immunoglobulin paraprotein were present, results from the Coomassie Blue methods were up to 50% lower than with the biuret method; increased dye concentration did not improve comparability substantially, but the addition of sodium dodecylsulphate reduced the bias to about 20%. When neither free light chain protein nor immunoglobulin paraprotein was present, results from the Coomassie Blue methods were only about 30% lower. The addition of sodium dodecylsulphate reduced this bias to 10%. Correlations between the biuret and the Coomassie Blue method were best when the Coomassie Blue reagent contained 40 mg/L sodium dodecylsulphate (r better than 0.98 in all groups; p less than 0.001).

Mitochondrial creatine kinase in cancer patients

We have developed a quantitative immunoassisted enzyme assay to screen for creatine kinase isoenzymes BB (CK-BB) and mitochondrial (CK-m) using commercial antibodies and reagents. Presence of CK-m activity was subsequently confirmed by electrophoretic separation of samples with elevated values. A prospective clinical trial was undertaken in 117 subjects: Normal (30), cirrhosis patients (30), myocardial infarction patients (30), and untreated oncology patients with metastatic malignancy (27). In 12 patients with malignancy CK-m activities were elevated; all had adenocarcinomas. No significant activity was detected in patients with other malignancies. CK-m positive tumour patients had a significantly higher mortality rate, and in two instances death was preceded by a sudden rise in CK-m activity. We suggest CK-m is a marker of adenocarcinoma and its presence in serum signifies increased mortality.

The fowl (Gallus domesticus) and a lepidopteran (Setomorpha rutella) as experimental hosts for Tetrameres mohtedai (Nematoda)

The life-cycle of Tetrameres mohtedai in the fowl involving a hitherto unknown intermediate host, Setomorpha rutella, is described and methods for laboratory demonstration are given. Development to infectivity in the intermediate host took less than 2 weeks under laboratory conditions. Infections could be established using infective larvae dissected from the intermediate host. The pre-patent period in the fowl averaged 36 days. Experimental evidence is given for infection of the final host by ingestion of either infected adult or infected larval Setomorpha. Development of the parasite to the infective stage does not depend on metamorphosis of the intermediate host.