Meta-analysis of the prevalence of renal cancer detected by abdominal ultrasonography

BACKGROUND

The potential for an ultrasound-based screening programme for renal cell carcinoma (RCC) to improve survival through early detection has been the subject of much debate. The prevalence of ultrasound-detected asymptomatic RCC is an important first step to establishing whether a screening programme may be feasible.

METHODS

A systematic search of MEDLINE and Embase was performed up to March 2016 to identify studies reporting the prevalence of renal masses and RCC. Two populations of patients were chosen: asymptomatic individuals undergoing screening ultrasonography and patients undergoing ultrasonography for abdominal symptoms not related to RCC. A random-effects meta-analysis was performed. Study quality was evaluated using a validated eight-point checklist.

RESULTS

Sixteen studies (413 551 patients) were included in the final analysis. The pooled prevalence of renal mass was 0·36 (95 per cent c.i. 0·23 to 0·52) per cent and the prevalence of histologically proven RCC was 0·10 (0·06 to 0·15) per cent. The prevalence of RCC was more than double in studies from Europe and North America than in those from Asia: 0·17 (0·09 to 0·27) versus 0·06 (0·03 to 0·09) per cent respectively. Data on 205 screen-detected RCCs showed that 84·4 per cent of tumours were stage T1-T2 N0, 13·7 per cent were T3-T4 N0, and only 2·0 per cent had positive nodes or metastases at diagnosis.

CONCLUSION

At least one RCC would be detected per 1000 individuals screened. The majority of tumours identified are early stage (T1-T2).

An evidence synthesis approach to estimating Hepatitis C Prevalence in England and Wales

In England and Wales, routine monitoring has been consistently showing an increase in mortality and morbidity due to infection with the Hepatitis C Virus (HCV). However, the magnitude of the underlying epidemic is still the subject of debate. In this paper we present estimates of the number of individuals aged 15—59 chronically infected with HCV in 2003, derived from a Bayesian synthesis of information available from multiple sources on the size of the groups at risk for HCV and the risk specific anti-HCV prevalence. Results show that the number of chronic infections is of the order of 142,000 (95% CrI: 90,000, 231,000), with the majority (85%, 95% CrI: 74%, 93%) in injecting drug users and about 80% (95% CrI: 74%, 84%) in the age group 15—44.

Response rates to combination therapy for chronic HCV infection in a clinical setting and derivation of probability tables for individual patient management

Evidence for efficacy of established treatment guidelines for chronic hepatitis C virus (HCV) disease is based on multinational randomized controlled trials (RCTs). Strategies for managing HCV, however, require an assessment of the effectiveness of intervention in routine clinical practice. We report the outcomes of combination therapy in a large cohort of HCV-infected individuals in the UK. A total of 347 (113 genotype 1, 234 genotype non-1) patients were treated with pegylated interferon and ribavirin according to current guidelines. Forty-two (37.2%) of those with genotype 1 infection and 164 (70.1%) with genotype non-1 infection achieved sustained viral response (SVR). Thirty-nine (11%) patients withdrew from treatment. In addition to viral genotype, factors predictive of a response to therapy were age at start of treatment and disease stage on pretreatment liver biopsy. Multivariate regression analysis demonstrated that the effects of age [odds ratio 0.5; 95% confidence interval (0.31-0.82) per 10-year increment (P = 0.006)] were confined to genotype 1 disease. In order to further inform the management of the individual patient, a multivariate logistic model was used to predict the probability of SVR for subgroups defined by disease stage, genotype and age at commencement of therapy. This model revealed striking differences in predicted response rates between subgroups and provided a strong rationale for early treatment, particularly for those with genotype 1 disease. Our study demonstrates that results comparable with those of RCTs can be achieved in clinical practice, and suggests that prediction of response rates based on probability modelling will provide a valuable adjunct to individual patient management.

Cost effectiveness of interferon alpha or peginterferon alpha with ribavirin for histologically mild chronic hepatitis C

BACKGROUND

For patients with mild chronic hepatitis C the cost effectiveness of antiviral therapy is unknown.

AIMS

To assess whether antiviral therapy (either interferon alpha or peginterferon alpha combined with ribavirin) is cost effective at a mild stage compared with waiting and only treating those cases who progress to moderate disease.

PATIENTS

Cases with mild chronic hepatitis C.

METHODS

A cost effectiveness model which estimates long term costs and outcomes for patients with mild chronic hepatitis C. The model uses effectiveness and cost data from the UK mild hepatitis C randomised controlled trial, combined with estimates of disease progression and cost from observational studies.

RESULTS

Antiviral treatment at a mild rather than a moderate stage improved outcomes measured by quality adjusted life years (QALYS) gained. The mean cost per QALY gained from antiviral treatment with interferon alpha-2b and ribavirin, compared with no treatment at a mild stage, was 4535 pounds sterling (7108 dollars) for patients with genotype non-1 and 25,188 pounds sterling (39,480 dollars) for patients with genotype 1. Providing peginterferon alpha-2b and ribavirin at a mild rather than a moderate stage was also associated with a gain in QALYS; the costs per QALY gained were 7821 pounds sterling (12,259 dollars) for patients with genotype non-1 and 28,409 pounds sterling (44,528 dollars) for patients with genotype 1.

CONCLUSIONS

For patients with chronic hepatitis C, it is generally more cost effective to provide antiviral treatment at a mild rather than a moderate disease stage. For older patients (aged 65 years or over) with genotype 1, antiviral treatment at a mild stage is not cost effective.

A drug-responsive and protease-resistant peripheral NADH oxidase complex from the surface of HeLa S cells

Our laboratory described a ca. 34-kDa protein of the HeLa S cell surface that bound an antitumor sulfonylurea N-(4-methylphenylsulfonyl)-N'-(4-chlorophenyl) urea (LY181984) with high affinity and that exhibited NADH oxidase and protein disulfide-thiol interchange activities also inhibited by LY181984. The quinone site inhibitor 8-methyl-N-vanillyl-6-noneamide (capsaicin) also blocked these same enzymatic activities. Using capsaicin inhibition as the criterion, the drug-responsive oxidase was released from the surface of HeLa S cells and purified. The activity of the released capsaicin-inhibited oxidase was resistant to heating at 50 degrees C and to protease digestion. After heating and proteinase K digestion, the activity was isolated in >90% yield by FPLC as an apparent 50- to 60-kDa multimer. Final purification by preparative SDS-PAGE yielded a capsaicin-inhibited NADH oxidase activity of a specific activity indicative of >500-fold purification relative to the plasma membrane. The final activity correlated with a ca. 34-kDa band on SDS-PAGE. Matrix-assisted laser desorption mass spectroscopy as well as reelectrophoresis of the 34-kDa band indicated that the ca. 34-kDa material was a stable mixture of 22-, 17-, and 9.5-kDa components which occasionally migrated as a ca. 52-kDa complex. The purified complex tended to multimerize and formed insoluble 10- to 20-nm-diameter amyloid rods. The components of the purified 34-kDa complex were blocked to N-terminal amino acid sequencing and were resistant to further protease digestion. After multimerization into amyloid rods, the protein remained resistant to proteases even under denaturing conditions and to cyanogen bromide either with or without prior alkylation.

Aqueous two-phase partition and detergent precipitation of a drug-responsive NADH oxidase from the HeLa cell surface

The partitioning behaviour of a drug (capsaicin)-responsive NADH oxidase (tNOX) activity released from HeLa cells by low pH treatment followed by heat and proteinase K was determined. When partitioned in a standard 6.4% PEG 3350/6.4% dextran T-500 two-phase system, the bulk of the tNOX activity was in the dextran-rich lower phase. The activity was inhibited by and bound to the triazine dye, Cibacron blue. Affinity partition, where the Cibacron blue was coupled to amino PEG 5000 and added to the first two-phase separation step, resulted in the partitioning of activity to the upper PEG phase. A second partition with PEG-salts resulted in the release of the tNOX from the Cibacron blue amino PEG enriched phase into the salt-enriched lower phase. The phase-purified protein exhibited anomalous behavior and tended to multimerize in sodium dodecyl sulphate (SDS) prior to SDS-polyacrylamide gel electrophoresis (PAGE). Multimerization appeared to be enhanced by PEG. The multimerization was enhanced with the reduced protein in the presence of detergent prior to SDS-PAGE. In addition, the activity was precipitated by PEG 8000 at concentrations between 6 and 30% by weight. In the presence of or after exposure to PEG 3350 or PEG 8000, the protein could not be detected by Western blot analysis after SDS-PAGE suggesting that the protein failed to enter the gel even though other HeLa cell surface proteins were unaffected. The anomalous multimerization behavior has thus far precluded the use of phase partition as a practical purification step for the oxidase.

A protein disulfide-thiol interchange activity of HeLa plasma membranes inhibited by the antitumor sulfonylurea N-(4-methylphenylsulfonyl)-N'-(4-chlorophenyl) urea (LY181984)

Plasma membrane vesicles isolated from HeLa cells grown in suspension culture contain a protein disulfide-thiol interchange (protein disulfide-like) activity. The activity was estimated from the restoration of activity to inactive (scrambled) pancreatic RNAase. RNAase activity was measured either by hydrolysis of cCMP or by a decrease in acid precipitable yeast RNA. The ability of plasma membrane vesicles to restore activity to inactive (scrambled) pancreatic ribonuclease was inhibited by the antitumor sulfonylurea N-(4-methylphenylsulfonyl)-N'-(4-chlorophenyl)urea (LY181984). The activity correlated with that of a cyanide-resistant NADH oxidase also associated with the plasma membrane vesicles that exhibited a similar pattern of drug response. The activity was stimulated by reduced glutathione and inhibited by oxidized glutathione but did not depend on either for activity. The antitumor sulfonylurea-inhibited activity was greatest in the presence of reduced glutathione and least in the presence of oxidized glutathione. The antitumor sulfonylurea-inhibited activity was unaffected by a monoclonal antibody to protein disulfide isomerase. Also the antitumor sulfonylurea-inhibited activity was unaffected by peptide antisera to the consensus active site sequence of protein disulfide isomerase. Thus the antitumor sulfonylurea-inhibited activity appeared to reside with a novel cell surface protein capable of oxidation of both NADH and protein thiols and of carrying out a protein disulfide isomerase-like protein disulfide-thiol interchange activity in the absence of NADH or other external reductants.

Response of a protein disulfide isomerase-like activity of transitional endoplasmic reticulum to all-trans retinol

Isolated membrane fractions enriched in vesicles of transitional endoplasmic reticulum from rat liver exhibited protein disulfide isomerase-like activity of low specific activity. Activity was measured as the ability to restore activity to reduced, denatured and oxidized (scrambled) RNase. Submicromolar concentrations of retinol either stimulated or inhibited this activity depending on the composition of the redox buffer. In the presence of 1 microM reduced glutathione, micromolar concentrations of retinol stimulated the activity while higher or lower concentrations were less effective. With scrambled RNase, retinol was largely without effect in the absence of reduced glutathione or in the presence of oxidized glutathione. In the presence of NADH, retinol inhibited the protein disulfide-like activity over the same range of concentrations where retinol stimulated in the presence of reduced glutathione. These responses were observed with scrambled and inactive RNase and with reduced and inactive RNase as substrates. Also inhibited by retinol in these membrane preparations was their ability to oxidize NADH. Thus the retinol-modulated protein disulfide isomerase activity appears to correlate with the presence in transitional endoplasmic reticulum of an activity capable of oxidizing NADH in the presence of potassium cyanide that also was inhibited by submicromolar concentrations of retinol.

Chlorsulfuron blocks 2,4-D-induced cell enlargement and NADH oxidase in excised sections of soybean hypocotyls

Elongation of soybean hypocotyl sections induced by the auxin herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), was blocked by micromolar concentrations of the sulfonylurea herbicide chlorsulfuron (2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-trizin-2- yl)amino]carbonyl]benzenesulfonamide). The inhibition at equimolar concentrations of 2,4-D and chlorsulfuron was overcome by a 10- or 100-fold excess of 2,4-D. Stimulation by 2,4-D of an 2,4-D-responsive NADH-oxidase activity of the soybean plasma membrane also was blocked by the presence of concentrations of chlorsulfuron equimolar to the 2,4-D. Chlorsulfuron alone was largely without effect on either cell elongation or the auxin-stimulated NADH-oxidase activity over a range of chlorsulfuron concentrations. The results show a clear correlation between inhibition of auxin-stimulated cell elongation and the inhibition of an auxin-stimulated component of a plasma membrane NADH-oxidase activity.

Physiological stimuli of thirst and drinking patterns in ponies

The stimuli that elicit thirst were studied in four ponies. Nineteen hours of water deprivation produced an increase in plasma protein from 67 +/- 0.1 g/litre to 72 +/- 2 g/litre, a mean (+/- se) increase in plasma sodium from 139 +/- 3 to 145 +/- 2 mmol/litre and an increase in plasma osmolality from 297 +/- 1 to 306 +/- 2 mosmol/litre. Undeprived ponies drank 1.5 +/- 0.9 kg/30 mins; 19 h deprived ponies drank 10.2 +/- 2.5 kg/30 mins and corrected the deficits in plasma protein, plasma sodium and plasma osmolality as well as compensating for the water they would have drunk during the deprivation period. In order to determine if an increase in plasma osmolality would stimulate thirst, 250 ml of 15 per cent sodium chloride was infused intravenously. The ponies drank when osmolality increased 3 per cent and when plasma sodium rose from 136 +/- 3 mmol/litre to 143 +/- 3 mmol/litre. Ponies infused with 15 per cent sodium chloride drank 2.9 +/- 0.7 kg; those infused with 0.9 per cent sodium chloride drank 0.7 +/- 0.5 kg. In order to determine if a decrease in plasma volume would stimulate thirst, ponies were injected with 1 or 2 mg/kg bodyweight (bwt) frusemide. Plasma protein rose from 68 +/- 2 g/litre pre-injection to 75 +/- 2 g/litre 1 h after 1 mg/kg bwt frusemide and to 81 +/- 1 g/litre 1 h after 2 mg/kg bwt frusemide.(ABSTRACT TRUNCATED AT 250 WORDS)