High-sensitivity salinity sensor based on optical microfiber coil resonator

A simple, compact, and high-sensitivity optical sensor for salinity measurement is reported based on an optical microfiber coil resonator (MCR). The MCR is manufactured by initially wrapping microfiber on a polymethylmethacrylate (PMMA) rod, which is dissolved to leave a hollow cylindrical fluidic channel within the coil for measurement. Based on the light propagation through the MCR, the device's spectrum moves to long wavelengths with increased salinity in the fluid. The MCR device's sensitivity can reach up to 15.587 nm/% with a resolution of 1.28 × 10^-3%. It is also confirmed that the temperature dependence is 79.87 pm/°C, which results from the strong thermal-expansion coefficient of the low refractive index epoxy. The experimental results indicate that the device can be widely used as a high sensitivity salinity sensor in water and other liquids due to its stability, compactness, electromagnetic immunity, and high sensitivity.

Transmission of HIV Drug Resistance and the Predicted Effect on Current First-line Regimens in Europe

Transmitted human immunodeficiency virus drug resistance in Europe is stable at around 8%. The impact of baseline mutation patterns on susceptibility to antiretroviral drugs should be addressed using clinical guidelines. The impact on baseline susceptibility is largest for nonnucleoside reverse transcriptase inhibitors.

Background. Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore, guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD program systematically collects data to gain insight into TDR occurring in Europe since 2001.

Methods. Demographic, clinical, and virological data from 4140 antiretroviral-naive human immunodeficiency virus (HIV)–infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002 to 2007. Baseline susceptibility to antiretroviral drugs was predicted using the Stanford HIVdb program version 7.0.

Results. The overall prevalence of TDR did not change significantly over time and was 8.3% (95% confidence interval, 7.2%–9.5%) in 2008–2010. The most frequent indicators of TDR were nucleoside reverse transcriptase inhibitor (NRTI) mutations (4.5%), followed by nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations (2.9%) and protease inhibitor mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine, respectively, independent of current NRTI backbones.

Conclusions. Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affected.

High uptake of hepatitis C virus treatment in HIV/hepatitis C virus co-infected patients attending an integrated HIV/hepatitis C virus clinic

Hepatitis C virus (HCV) is a major cause of liver disease in HIV-infected patients. The HCV treatment outcomes and barriers to HCV referral were examined in a centre with a HIV/HCV co-infection clinic. Patients who were antibody positive for both HIV and HCV between 1987 and January 2009 were identified. A retrospective chart review was undertaken. Multivariate analysis was performed to assess predictors of HCV clinic referral. Data were collected on 386 HIV/HCV patients; 202/386 had been referred to the co-infection clinic and 107/202 had HCV treatment. In addition, 29/202 were undergoing pretreatment work-up. Overall sustained virologic response (SVR) was 44%; SVR was equivalent in those who acquired HIV/HCV infection from intravenous drug use (IDU) and others. On multivariate analysis, patients who missed appointments, were younger, with active IDU and advanced HIV and who were not offered HCV treatment were less likely to be referred to the clinic. Patients attending the clinic were more likely to have been screened for hepatocellular carcinoma than those attending the general HIV service. Two-thirds of patients referred to the clinic had engaged with the HCV treatment programme. Dedicated co-infection clinics lower the threshold for treatment and improve management of liver disease in co-infected patients.

The advent of successful organ transplantation in the Irish HIV positive cohort

BACKGROUND

Liver disease is an increasing cause of morbidity and mortality in Human immunodeficiency virus (HIV) positive patients.

AIM

To describe the first cases of organ transplantation in HIV positive patients in Ireland.

METHOD

We report the Irish patients with HIV who received liver transplantation and performed a chart review.

RESULT

Two patients received liver transplantation for end stage liver disease caused by Hepatitis C, with survival at 2 years of 100%.

CONCLUSION

Liver transplantation is a feasible treatment for patients with HIV and end stage liver disease. The success of transplantation in the HIV positive population should encourage the provision of other medical and surgical interventions previously not offered to patients with HIV.

The characteristics, management and outcomes of people identified with mental health issues in an emergency department, Melbourne, Australia

Although the number of mental health presentations to emergency departments is increasing as a result of the integration of psychiatric services with general services, few studies have explored the characteristics of mental health patients presenting to emergency departments in Australia. This study investigated the characteristics of, and outcomes in relation to, people presenting with a mental health problem to one large metropolitan emergency department. Data were collected from the emergency department's electronic records system for adult patients aged 18-65 years old with an emergency department discharge diagnosis of a mental health disorder, including substance abuse and psychosocial crisis, for two months. Mental health patients totalled 5.3% (n= 290) of adult presentations to the emergency department. Over half were male; mean age 37.4 years; 49% were allocated triage category 3/urgent; 45% arrived by ambulance; 39% were overdosed/intoxicated and 55% received one or more diagnostic investigations. Patients who were intoxicated, those who arrived after hours, or patients admitted to a mental health ward were more likely to wait longer than 8h. Findings are broadly in line with that reported for other Australian studies, although the present findings suggest that patients had significantly more routine investigations and there were higher rates of presentations for 'intoxication'.

Role of rapid virological response in prediction of sustained virological response to Peg-IFN plus ribavirin in HCV / HIV co-infected individuals

The objective of the study was to evaluate the role of rapid virological response (RVR) in predicting sustained virological response (SVR) rates to hepatitis C virus (HCV) therapy. 65 HIV / HCV co-infected patients commenced HCV treatment per protocol. HIV / HCV patients with a mean CD4 count of 502 were treated for 24-48 weeks depending on genotype. Virological response was assessed at weeks 4 (RVR), 12 [early virological response (EVR)], 24, at end of treatment (EOTR) and 24 weeks post-completion of treatment (SVR). Primary end-point was defined as undetectable HCV RNA at 24 weeks post-treatment completion. Fifty-five per cent of co-infected patients were on highly active anti-retroviral therapy. A majority of patient group were male. 60% of HIV / HCV patients achieved SVR (35% genotype 1 / 4; 77% genotype 2 / 3). 24 HIV / HCV patients achieved undetectable HCV levels compared with baseline by week 4. The positive predictive value (PPV) of RVR at week 4 for subsequent SVR in HIV-HCV co-infected patients was 100%; the negative predictive value (NPV) was 57%. Significant variables associated with SVR were: (i) lower median pre-treatment HCV viral load, (ii) genotype 2 / 3 disease and (iii) achievement of RVR. Independent variables associated with RVR were low pre-treatment HCV viral load and genotype 2 / 3 disease. Achievement of RVR, a negative HCV-PCR, at week 4 of treatment is predictive of SVR in this cohort of patients. This may be used to guide optimal treatment duration in patient groups. More significantly, the data serve to highlight the subgroup of patients who, on achieving RVR, should be actively supported to complete HCV treatment with full dose therapy, especially patients co-infected with G2 / 3 disease for whom 6 months' full dose therapy may be sufficient to obtain a SVR.

Haematological support during peg-interferon therapy for HCV-infected haemophiliacs improves virological outcomes

Hepatitis C virus-infected haemophiliacs are traditionally under represented in international treatment studies thus data assessing response to pegylated-interferon (peg-IFN) and ribavirin (RBV) in HCV mono-infected or HCV/HIV co-infected haemophiliacs are few. Since 2001, 37 haemophiliac patients have received peg-IFN and RBV according to centre-based investigator initiated protocols. Primary end points were: early virological response (EVR); end of treatment response (EOTR) and sustained virological response (SVR). An intention-to-treat analysis was used. Secondary end points were adverse events, haemopoietic stem cell growth factor use, therapy discontinuations and dose reductions. Hepatitis C virus mono-infection group (Mono-I) numbered 20 (60% genotype 1). HCV/HIV co-infected group (Co-I) numbered 17 (59% genotype 1/4). Primary end points were: EVR 76%, EOTR 70% and SVR 43%. Comparison of Mono-I to Co-I demonstrated: EVR rates of 70% and 82%, respectively; EOTR rates of 65% and 76%, respectively, and SVR rates of 35% and 53%, respectively. SVR rates genotype 1/4 group - 17% (Mono-I) vs. 30% (Co-I); SVR rates genotype 2/3 group - 63% (Mono-I) vs. 86% (Co-I). Therapy discontinuations: six of 20 (30%) Mono-I vs. three of 17 (18%) Co-I. Dose reductions: two of 20 (10%) Mono-I vs. zero of 17 Co-I. Haematological support factor use: one of 20 (5%) Mono-I vs. four of 17 (23.5%) Co-I. Virological outcomes to peg-IFN and RBV in HCV-infected haemophiliacs are comparable to published data relating to other HCV-infected cohorts. Good virological outcomes can be achieved in HIV co-infected haemophiliacs particularly when growth factors are used to facilitate full dosing of peg-IFN and RBV.

Role of individualization of hepatitis C virus (HCV) therapy duration in HIV/HCV-coinfected individuals*

OBJECTIVE

The aim of this study was to assess the efficacy, safety and tolerability of pegylated interferon and ribavirin in HIV/hepatitis C virus (HCV)-coinfected patients, prescribed for the same duration and at the same dosage as that used in HCV monoinfection studies.

DESIGN

It was an open-label, single-centre, prospective study.

METHODS

Forty-five patients coinfected with HIV and HCV with CD4 counts >200 cells/microL were treated with pegylated interferon-alpha2b 1.5 microg/kg/week and ribavirin 1000-1200 mg/day for 24-48 weeks depending on HCV genotype. Safety and tolerability were assessed weekly for the first month and monthly thereafter. Virological response was assessed at weeks 4, 12 and 24 and at the end of treatment and 12 and 24 weeks post completion of treatment. The primary endpoint was defined as undetectable HCV RNA at 24 weeks post completion of treatment [sustained virological response (SVR)].

RESULTS

The majority of patients were male and had been injecting drug users. Sixty per cent were on antiretroviral therapy. In an intention-to-treat analysis, 53% had an SVR (genotype 1, 19% and genotype 2/3, 75%). All patients who had undetectable HCV RNA at week 4 of HCV treatment [very early virological response (VEVR)] had a SVR. On multivariate analysis only HCV genotype predicted SVR. Adverse events occurred frequently.

CONCLUSIONS

These results indicate that 24 weeks of HCV treatment may be adequate for HIV-infected individuals coinfected with HCV genotype 2 or 3. VEVR can predict SVR in this group and may be used to guide the subgroup of genotype 2/3 individuals who will respond to 24 weeks of treatment.

Racial differences in responses to interferon-beta-1a in chronic hepatitis C unresponsive to interferon-alpha: a better response in Chinese patients

Re-treatment with interferon-alpha alone for chronic hepatitis C nonresponders to interferon-alpha monotherapy is almost ineffective. This multicentre, randomized, parallel-group, dose-finding study evaluated the efficacy of interferon-beta-1a in the treatment of chronic hepatitis C patients unresponsive to interferon-alpha. A total of 267 patients were randomized to one of four groups: subcutaneous interferon-beta-1a 12 MIU (44 microg) or 24 MIU (88 microg) administered three times weekly or daily. Patients were treated for 48 weeks and then followed up for an additional 24 weeks. There was a trend towards a dose-response relationship regarding virological [loss of detectable serum hepatitis C virus (HCV) RNA] and biochemical response (normalization of serum alanine aminotransferase). Overall, 22 patients (8.3%) had a virological response at the end of treatment; nine patients (3.4%) had a sustained virological response (SVR). Strikingly, 21.7% (5/23) of Chinese patients achieved SVR. Univariate analysis revealed that race was the only variable related to SVR [odds ratio (OR) 16.6; 95% CI 4.1-67.3; P < 0.0001]. Multiple logistic regression analysis also confirmed that more Chinese patients achieved SVR than non-Chinese patients (OR 12.3; 95% CI 2.6-59.3; P = 0.0017). In addition, complete clearance of HCV-RNA occurred earlier in Chinese than in non-Chinese responders (median 2 vs 30 weeks; P = 0.020). Thirty-six patients were withdrawn from treatment because of adverse events. Most adverse events were mild or moderate in severity. In conclusion, interferon-beta-1a provided considerable clinical benefit in Chinese patients with chronic hepatitis C unresponsive to interferon-alpha. The evaluation of interferon-beta-1a in this setting is progressing.

Cystic fibrosis mutation frequencies in an Irish population

The incidence of cystic fibrosis (CF) at birth in Ireland is 1/1461. Neonate CF genetic testing is not routinely performed in Ireland. Currently, screening is only carried out where there is clinical evidence or a family history to suggest disease. Here we report the frequencies of common CF mutations occurring in an Irish population composed of samples collected from western, mid-western and southern regions of Ireland. Rarer CF mutations were also identified in a selected number of CF patients. In addition, a number of polymorphisms were identified, some of which are reported to be functionally and phenotypically important.

Hepatitis B e antigen seroconversion: effects of lamivudine alone or in combination with interferon alpha

Seroconversion of hepatitis B e antigen (HBeAg) is an important marker for resolution of active hepatitis B virus (HBV) infection and for a long-term positive response to treatment. Lamivudine, a nucleoside analogue, is the first effective oral treatment for chronic hepatitis B in patients with evidence of viral replication and liver disease. When appropriate patient groups are compared, treatment with lamivudine for 1 year leads to HBeAg seroconversion in a similar proportion of patients as a standard course of interferon (IFN) alpha therapy. Seroconversion increases during prolonged therapy (up to 3 years), and is sustained post-treatment in more than three-quarters of patients. Response rates are related to the pretreatment level of serum alanine aminotransferase (ALT) and reach 65% in those patients with serum ALT > 5 x upper limit of normal (ULN) after one year. For patients with pretreatment ALT > 2 x ULN, response was seen in 38% after one year, rising to 65% after 3 years. To date, combination with IFN and lamivudine has not been shown to confer additional benefit compared with lamivudine monotherapy. Lamivudine is effective and appropriate for use in a greater proportion of HBV infected patients than IFN alpha, particularly those infected at birth or in early childhood. Furthermore, because seroconversion after lamivudine is not normally associated with a severe flare of liver disease, as seen with IFN, it is more suitable for use in patients with active liver disease and cirrhosis. In conclusion, lamivudine is more suitable than IFN for a broad range of patients, including those with severe liver disease, recurrent flares, pre-core mutant HBV and those who have failed previously IFN treatment or are immunosuppressed. Lamivudine is also better tolerated than IFN.

Hepatitis B e antigen seroconversion: effects of lamivudine alone or in combination with interferon alpha

Seroconversion of hepatitis B e antigen (HBeAg) is an important marker for resolution of active hepatitis B virus (HBV) infection and for a long-term positive response to treatment. Lamivudine, a nucleoside analogue, is the first effective oral treatment for chronic hepatitis B in patients with evidence of viral replication and liver disease. When appropriate patient groups are compared, treatment with lamivudine for 1 year leads to HBeAg seroconversion in a similar proportion of patients as a standard course of interferon (IFN) alpha therapy. Seroconversion increases during prolonged therapy (up to 3 years), and is sustained post-treatment in more than three-quarters of patients. Response rates are related to the pretreatment level of serum alanine aminotransferase (ALT) and reach 65% in those patients with serum ALT > 5 x upper limit of normal (ULN) after one year. For patients with pretreatment ALT > 2 x ULN, response was seen in 38% after one year, rising to 65% after 3 years. To date, combination with IFN and lamivudine has not been shown to confer additional benefit compared with lamivudine monotherapy. Lamivudine is effective and appropriate for use in a greater proportion of HBV infected patients than IFN alpha, particularly those infected at birth or in early childhood. Furthermore, because seroconversion after lamivudine is not normally associated with a severe flare of liver disease, as seen with IFN, it is more suitable for use in patients with active liver disease and cirrhosis. In conclusion, lamivudine is more suitable than IFN for a broad range of patients, including those with severe liver disease, recurrent flares, pre-core mutant HBV and those who have failed previously IFN treatment or are immunosuppressed. Lamivudine is also better tolerated than IFN.

Lamivudine and alpha interferon combination treatment of patients with chronic hepatitis B infection: a randomised trial

BACKGROUND, AIM, AND METHODS: Alpha interferon is the generally approved therapy for HBe antigen positive patients with chronic hepatitis B, but its efficacy is limited. Lamivudine is a new oral nucleoside analogue which potently inhibits hepatitis B virus (HBV) DNA replication. To investigate the possibility of an additive effect of interferon-lamivudine combination therapy compared with interferon or lamivudine monotherapy, we conducted a randomised controlled trial in 230 predominantly Caucasian patients with hepatitis B e antigen (HBeAg) and HBV DNA positive chronic hepatitis B. Previously untreated patients were randomised to receive: combination therapy of lamivudine 100 mg daily with alpha interferon 10 million units three times weekly for 16 weeks after pretreatment with lamivudine for eight weeks (n=75); alpha interferon 10 million units three times weekly for 16 weeks (n=69); or lamivudine 100 mg daily for 52 weeks (n=82). The primary efficacy end point was the HBeAg seroconversion rate at week 52 (loss of HBeAg, development of antibodies to HBeAg and undetectable HBV DNA).

RESULTS

The HBeAg seroconversion rate at week 52 was 29% for the combination therapy, 19% for interferon monotherapy, and 18% for lamivudine monotherapy (p=0.12 and p=0.10, respectively, for comparison of the combination therapy with interferon or lamivudine monotherapy). The HBeAg seroconversion rates at week 52 for the combination therapy and lamivudine monotherapy were significantly different in the per protocol analysis (36% (20/56) v 19% (13/70), respectively; p=0.02). The effect of combining lamivudine and interferon appeared to be most useful in patients with moderately elevated alanine aminotransferase levels at baseline. Adverse events with the combination therapy were similar to interferon monotherapy; patients receiving lamivudine monotherapy had significantly fewer adverse events.

CONCLUSIONS

HBeAg seroconversion rates at one year were similar for lamivudine monotherapy (52 weeks) and standard alpha interferon therapy (16 weeks). The combination of lamivudine and interferon appeared to increase the HBeAg seroconversion rate, particularly in patients with moderately elevated baseline aminotransferase levels. The potential benefit of combining lamivudine and interferon should be investigated further in studies with different regimens of combination therapy.

Prolonged treatment with interferon in patients with histologically mild chronic hepatitis C: a decision analysis

Short courses (6 months) of interferon (IFN) are highly cost-effective in patients with histologically mild chronic hepatitis C. However, IFN treatment lasting 12-24 months is now the standard of care. We utilized a previously published and validated model of the natural history of chronic hepatitis C and the treatment outcomes from two large multicentre treatment trials of IFN-alpha 2b, given for 6 months or 18-24 months, to estimate the incremental cost-effectiveness of prolonged IFN treatment in patients with histologically mild chronic hepatitis C (formerly chronic persistent or mild chronic active hepatitis). In the two treatment trials, pooled analysis of the patients with mild hepatitis showed that 36.4% of them normalized serum alanine aminotransferase and remained virus negative (sustained response) after completing an 18-24 month course of IFN vs 15.3% for a 6-month course and no response in the absence of treatment. The model then estimated that for patients aged 20-50 years, the discounted marginal cost per year of life gained by long-term IFN treatment ranged from US $735 to US $8856, and the gain in life expectancy ranged from 4.35 years to 0.75 years, respectively, compared with an untreated age-matched cohort. Compared with treatment for only 6 months, the incremental marginal cost per life year gained by longer treatment at age 20-50 years ranged from $938 to $9957. The treatment and healthcare costs, sustained response rates and the rate of progression during early disease were identified as significant variables in sensitivity analyses. However, longer treatment always showed a survival benefit compared with 6 months of IFN or no treatment, and the cost of longer treatment is reasonable compared with that for a 6-month course.

Factors affecting epirubicin pharmacokinetics and toxicity: evidence against using body-surface area for dose calculation

PURPOSE

An exploratory study to test whether body-surface area (BSA) should be used for the calculation of epirubicin dose.

PATIENTS AND METHODS

The relationship between pretreatment characteristics and the effects of epirubicin were investigated in 20 chemotherapy-naive patients. Measurements of body size, renal and hepatic function, and other factors were correlated with epirubicin pharmacokinetics (PK) and epirubicin-induced neutropenia. All patients received 150 mg of epirubicin infused continuously over 120 hours, regardless of body size. Factors were analyzed by univariate and multivariate linear regression.

RESULTS

There were no correlations between BSA or weight with any PK parameter or with the degree of neutropenia. In multivariate analysis, indicators of liver function were the only factors that correlated with neutropenia and epirubicin PK. Thus, correlations for neutropenia were seen with antipyrine clearance (P = .003), activated partial thromboplastin time (APTT) (P = .005) and serum transferrin (P = .01). Further, the area under the concentration-time curve (AUC) for epirubicin correlated with prothrombin index (P < .01), antipyrine clearance (P < .01), and serum bile salt concentration (P = .03), and there were similar correlations for epirubicin steady-state concentration (CpSS). Epirubicin clearance correlated with antipyrine clearance (P = .02). PK parameters for dihydroepirubicin correlated with prothombin index, serum transferrin, and bile salt concentrations (P < .001 for all correlations). Because of the number of statistical examinations performed, some of these correlations may be spurious. However, some are likely to be real, since the same variables repeatedly correlated with different epirubicin-associated outcomes. There were no correlations between epirubicin PK indices or neutropenia and serum aminotransferase levels or other biochemical liver function tests, creatinine, or any of the clinical factors examined.

CONCLUSION

These results led us to question the use of BSA for epirubicin dose calculation. In contrast, quantitative liver function tests may give a better indication of drug handling and toxicity and may be useful to determine more accurate methods for dose calculation of epirubicin.

Diterpenoids from germander, an herbal medicine, induce apoptosis in isolated rat hepatocytes

BACKGROUND & AIMS

Germander was withdrawn from the market after its use for weight control caused an epidemic of hepatitis. Its toxicity was shown to be caused by diterpenoids and their cytochrome P4503A-mediated metabolic activation into electrophilic metabolites that deplete cellular thiols. The aim of the present study was to determine the mechanisms of cell death.

METHODS

Isolated rat hepatocytes were incubated for 2 hours with germander diterpenoids (100 micrograms/mL).

RESULTS

Diterpenoids decreased cell glutathione, increased cytosolic [Ca2+], activated Ca(2+)-dependent tissue transglutaminase forming a cross-linked protein scaffold, and caused internucleosomal DNA fragmentation and the ultrastructural features of apoptosis. Cell death was prevented by decreasing metabolic activation (with troleandomycin), preventing depletion of glutathione (with cystine), blocking activation of Ca(2+)-modulated enzymes (with calmidazolium), or inhibiting internucleosomal DNA fragmentation (with aurintricarboxylic acid). Apoptosis was increased and diterpenoids caused overexpression of p53 and interleukin 1 beta-converting enzyme in rats treated with dexamethasone (cytochrome P4503A inducer). Apoptosis was also increased by a diet deficient in sulfur amino acids.

CONCLUSIONS

The germander furano diterpenoids cause apoptosis within 2 hours in isolated rat hepatocytes. Electrophilic metabolites may stimulate apoptosis by decreasing thiols, increasing [Ca2+], and activating Ca(2+)-dependent transglutaminase and endonucleases.

Efficacy and tolerance of a 6-month treatment course of daily interferon-alpha 2a for chronic hepatitis C with cirrhosis. The Australian Hepatitis C Study Group

Response to interferon-alpha (IFN-alpha) treatment in hepatitis C is poorer when cirrhosis is present. In the third Australian multicentre hepatitis C trial, Aushep-3, we examined the efficacy and tolerability of an intensive 24-week course of interferon-alpha 2a in Child-Pugh grade A patients with chronic hepatitis C and cirrhosis. This was an open uncontrolled trial of 4.5 million units (MU) of IFN-alpha 2a daily for 24 weeks; follow-up was 48 weeks. Chronic hepatitis C and cirrhosis were confirmed histologically. HCV RNA was determined in serum by reverse transcriptase polymerase chain reaction (PCR), and viral genotyping was by line-probe assay. Treatment response was defined as a reduction of alanine aminotransferase (ALT) to less than 1.5 times the upper limit of normal (and by at least 50% of pretreatment values) at weeks 20 and 24. Sustained response was defined as normal serum ALT after treatment from trial week 28 until week 48. Among the 56 patients, a treatment response occurred in 18 (32% by intention-to-treat; 42% of those who completed treatment) and eight (14%) had a sustained response. At 24 weeks, HCV RNA was not detectable in 12 of 17 treatment responders, and remained negative at 48 weeks in six of eight sustained responders. Treatment response by genotype occurred in 75% of patients with HCV type 2, in 38% with HCV type 3a and in 12% with HCV genotype 1. Sustained response occurred in only one (4%) patient with HCV genotype 1 but in five (20%) with genotypes 2 or 3a. Among 13 patients withdrawn, nine were for adverse effects, most often haematological; 10 others underwent dose reduction for adverse effects. It is concluded that a sustained biochemical and viral response to treatment with IFN-alpha 2a can be obtained in some patients with hepatitis C and cirrhosis, particularly those with genotypes 2 or 3a. Therefore, patients with cirrhosis should be considered for interferon treatment on an individual basis. Genotyping may improve case selection, but vigilance is required for haematological complications.

Telephoning a nursing department: callers' experiences

This preliminary, exploratory study examined the level of satisfaction of patients and relatives with the telephone communication skills of nurses. Results indicate that callers experienced several difficulties, particularly with regards to knowing who they were speaking to, being treated as an individual rather than just another caller, having their calls dealt with efficiently, or redirected correctly. It is suggested that nurse educators include training in telephone use in courses on communication skills.

Comparative study of three doses of interferon-alpha 2a in chronic active hepatitis B. The International Hepatitis Trial Group

To determine the efficacy of interferon-alpha 2a in chronic active hepatitis B, 238 patients were randomly divided, into four groups: three groups received either 2.5 MIU m-2, 5.0 MIU m-2 or 10.0 MIU m-2, three times weekly by intramuscular injection for 12-24 weeks; and a control group received no treatment. Patients were followed for up to 12 months after treatment was discontinued. There was a statistically significant difference in response [clearance of hepatitis B e antigen (HBeAg) and hepatitis B viral DNA (HBV-DNA)] between treated and untreated patients (37 vs 13%) but no statistically significant difference was seen between treatment groups (33%, 34% and 43% for the 2.5, 5.0 and 10.0 MIU m-2 groups, respectively). A transient rise in transaminases (seroconversion hepatitis) was seen in responders, but levels returned to within the normal range after response to treatment. In patients responding to interferon therapy there was a significant reduction in the severity of the hepatitis. Interferon-alpha 2a was generally well tolerated with respect to vital signs and laboratory parameters.

The effect of posture on three objective audiological measures

This study examines the effect of posture on click evoked otoacoustic emissions, tympanic membrane displacement, and travelling wave velocity obtained using the auditory brainstem response. Statistically significant changes with posture were observed for each technique. The changes in evoked emission and tympanic membrane displacement measurements were comparable with those reported by previous experiments. Travelling wave velocity measurements were shown to be sensitive to inferred posturally-induced changes in labyrinthine fluid pressure of around 150 mm saline. There was no statistically significant correlation between posturally-induced changes measured by the three techniques. It is suggested that different mechanisms are responsible for the posturally-induced changes observed for the three techniques.

Liver function tests in persons receiving anticonvulsant medications

Liver function tests were carried out in 206 adults and children taking anticonvulsants to ascertain the prevalence of biochemical abnormalities in asymptomatic patients. It was observed that serum gamma-glutamyl transpeptidase was elevated in 74.6% of patients, alkaline phosphatase in 29.7% and alanine aminotransferase in 25.2% of cases. These figures are similar to those previously reported in the literature and probably reflect hepatic enzyme induction by the anticonvulsants. It is suggested that there is no value in the routine performance of liver function tests in patients with epilepsy. However, such patients should be informed of the symptoms of hepatic dysfunction and asked to report for liver function tests should they have such symptoms.

Aggression: therapeutic response to verbal abuse

Increasing numbers of nurses in a variety of settings have to deal with physical and verbal aggression meted out by their patients. This article concentrates on suitable therapeutic responses to verbal abuse, and urges the nurse to consider aggression in a wider context, looking at the predisposing factors and methods to defuse potentially violent situations. The author stresses that self-evaluation is crucial if skills are to be learned and applied to subsequent episodes.

Isochronic mapping: a preliminary report of a new technique

A new technique which we have named 'isochronic mapping' is described. The conventional technique of plotting isopotential maps shows little or no contrast for far-field potentials such as the auditory brainstem response (ABR). However, by modifications to the mapping software, the latency values of a peak can be plotted and lines of equal time or isochronic maps can be produced. Data from a normal subject has been obtained for both the compound and derived ABRs and are described in detail. The data are clear but the time delays between earliest and latest projections of a peak are hard to interpret. For monaural click stimulation, wave JV of the ABR projects first to the contralateral side of the head then moves towards the stimulated ear arriving some 0.3 ms later. Possible interpretations of this finding are discussed but further experimentation is needed to develop our understanding of these data.

A non-invasive, objective test of endolymphatic hydrops

Our previous work has shown that auditory brainstem responses (ABRs) can be used to measure the basilar membrane travelling wave velocity (TWV). Based upon the hypothesis that increased pressure in the scala media will increase the stiffness of the basilar membrane and, hence, increase the speed of the travelling wave. ABRs have been used to provide a means of objectively testing for endolymphatic hydrops. Ten normally hearing subjects and 20 Meniere's patients were tested. The data for the Meniere's group show that the TWV was within normal limits at all frequencies tested, except 5.7 kHz. At this frequency, the TWV greatly exceeded that of the normal group. A short duration (15-30 min) clinical test has been developed which involves the recording of two masked brainstem responses and the measurement of the difference in wave V latencies. Clinical verification that the technique is valid was obtained by monitoring patients undergoing glycerol dehydration. The additional hardware to enable this test to be carried out with a standard evoked response system has been constructed and three, parallel, clinical trials are in hand. Currently, this technique is being applied to longitudinal studies of Meniere's patients and to evaluating the action and efficacy of various drugs. A double-blind trial using a placebo and two different drugs is underway and preliminary results are presented here.

Apparent travelling wave velocity changes in cases of endolymphatic hydrops

This study attempted to develop a test which would be specific for endolymphatic hydrops. It is based upon the hypothesis that increased pressure in the scala media will alter the stiffness of the basilar membrane and hence increase the speed of the travelling wave. Auditory brainstem-derived responses were used to measure the basilar membrane travelling wave velocity in normals and to take the equivalent measures in Meniere's patients. Ten normally hearing subjects and 20 Meniere's patients were tested. The data for the Meniere's group showed that the travelling wave velocities were within normal limits at all frequencies tested, except 5.7 kHz where the travelling wave velocity greatly exceeded that of the normal group. A theoretical possibility that these findings may be the result of damaged and broadened VIIIth nerve tuning curves is discussed but travelling wave measures and psychophysical tuning curve measurements on the Meniere's group, normals and noise-induced hearing loss (NIHL) cases showed that this was not a significant factor. The data indicate that this technique can detect endolymphatic hydrops and a short duration clinical procedure has been devised.

Verification of a new test of endolymphatic hydrops

A new objective test of endolymphatic hydrops has been described previously. The test uses auditory brain-stem response (ABR) techniques to estimate the basilar membrane travelling wave velocity (TWV). The underlying hypothesis is that raised pressure in the scala media will lead to an increase in the stiffness of the basilar membrane and that this will give rise to a travelling wave velocity that is greater than normal. It was considered that verification of the technique could be obtained by carrying out the new test before and during a glycerol dehydration procedure. Patients who required this procedure for verification of the diagnosis or as a prognostic indicator for sacculotomy, underwent the following tests. Prior to dehydration an audiogram, the ABR TWV test and a blood sample (for plasma osmolality) were taken. The patient was then given the appropriate amount of glycerol mixed with lemon juice and laid on a bed in a test room. The audiogram and a blood sample were repeated every hour and the ABR TWV test was repeatedly carried out every twenty minutes between the other tests. Six of these procedures have been carried out. In five of them the 0.5 and 1 kHz average threshold improved by at least 10dB and in all those cases the ABR TWV test showed an abnormal pre-dehydration result which moved towards the normal value following dehydration. One patient gave ABR TWV results that were within normal limits before and during the procedure and gave an audiometric change of only 5dB.(ABSTRACT TRUNCATED AT 250 WORDS)

Halothane hepatitis: damage to peripheral blood mononuclear cells produced by electrophilic drug metabolites is Ca(2+)-dependent

Peripheral blood mononuclear (PBM) cells from patients with halothane hepatitis are unusually susceptible to damage from phenytoin metabolites generated by an in vitro drug metabolising system. In order to provide more information about the nature of this susceptibility factor, the effect of removing calcium ions (Ca2+) from the incubation medium of the test system was examined. Phenytoin metabolites were generated by incubating phenytoin with beta-naphthoflavone-induced rat liver microsomes in the presence of 1,1,1-trichloropropene oxide (TCPO), an epoxide hydrase inhibitor. When PBM cells from patients who had recovered from halothane hepatitis were incubated in this system and then maintained in Ca(2+)-containing tissue culture medium (without alpha-tocopherol) for 16 h, cell death, as measured by trypan blue exclusion, was greatly increased (53% and 78% at 0.06 mmol/l and 0.12 mmol/l phenytoin, respectively) compared with control incubations (TCPO omitted). Removal of Ca2+ from the tissue culture medium effectively abolished reactive metabolite-induced cell death. Resting cytosolic free Ca2+ concentration in PBM cells was also measured using the quin-2 fluorescence method and total Ca2+ content was measured by atomic absorption spectrometry. Although variability appeared greater among patients, mean values for these parameters among 12 patients with halothane hepatitis did not differ from controls. It is concluded that enhanced permeability of PBM cells to extracellular Ca2+ may be an important factor in the pathogenesis of drug metabolite-induced cell death in patients susceptible to halothane hepatitis. Such permeability to Ca2+ is not evident in resting cells and presumably results from an interaction between electrophilic metabolites and the pumps which regulate cell calcium homeostasis.

Clinical methods for the objective estimation of loudness discomfort level (LDL) using auditory brainstem responses in patients

Our previous work showed that the slope of the JV latency/intensity function can be used to estimate the loudness discomfort level (LDL). In this study, the previous work was repeated using normal subjects and patients whose LDL was unknown at the time of test. The results showed that the original model still applied. Further measures were taken to evaluate clinical methods of applying this technique. Four basic approaches were used, a 'correction factor' model and a 'curve-fitting' model and these were applied to data obtained from measurements taken in both 5 dB and 10 dB increments. The results showed that the 'correction factor' models were better than the 'curve-fit' approach. The prediction of LDL based upon the 5 dB increment data gave the greater accuracy but the 10 dB increment data gave predictions that were sufficiently accurate for clinical use (95% confidence limits of +/- 8 dB). Thus this ABR estimator has wide application and good accuracy in estimating subjective LDL. A clinical protocol for applying this technique is described.

Hepatic testosterone metabolism in male rats with portal bypass

This study was performed to ascertain whether testosterone metabolism is altered in male rats with portal bypass, and whether such changes could contribute to the reduction in serum testosterone concentration and raised serum estrogen levels that are observed in this situation. The metabolic clearance rate of testosterone was determined by a prime-dose constant-infusion technique in male rats subjected to complete portal vein ligation and in sham-operated controls. Testosterone clearance was similar in rats with portal vein ligation and control rats (9.01 +/- 2.29 and 8.26 +/- 2.83 ml/min, respectively) but the clearance per gram of liver was greater in rats with portal vein ligation than in controls (1.18 +/- 0.18 versus 0.68 +/- 0.24 ml/min.g liver, p less than 0.0001). After 180 min of [3H]testosterone infusion, [3H]estradiol comprised 1.2% of plasma total radioactivity in male controls but was increased to 11% in rats with portal vein ligation (p less than 0.005). Similarly, biliary excretion of [3H]estradiol was eightfold greater in male rats with portal vein ligation compared with controls (p less than 0.001). In control male rats, the major metabolites of testosterone present in bile were 2 alpha-hydroxytestosterone, 16 alpha-hydroxytestosterone, and 7 alpha-hydroxytestosterone. Portal bypass was associated with reduced biliary excretion of 2 alpha-hydroxytestosterone and 16 alpha-hydroxytestosterone to approximately 50% of control, but there was no change in the excretion of 7 alpha-hydroxytestosterone. Conversely, portal bypass was associated with increased formation of dihydrotestosterone, indicating stimulated activity of testosterone 5 alpha-reductase. It is concluded that portal bypass in male rats is associated with altered pathways of testosterone metabolism and, in particular, with increased aromatization of testosterone to estradiol. The site of such estradiol formation has not been determined by this in vivo study. However, selective changes occurred in the regiospecific and stereospecific hydroxylation pathways of testosterone and in 5 alpha-reductase activity after portal bypass in male rats. It is concluded that portal bypass, in the absence of parenchymal liver damage, results in demasculinization and feminization of C19 steroid metabolism in the male rat liver. These metabolic changes could be revelant to the pathogenesis of changes in sexual characteristics in cirrhosis.

The objective estimation of loudness discomfort level using auditory brainstem evoked responses

The loudness discomfort level (LDL) is of importance in the fitting of hearing aids, but very young children are unable to provide a subjective judgement of LDL. Therefore the relationship between Jewett wave V latency and subjective loudness was investigated to ascertain if objective estimation of LDL is possible. ABR recordings were taken from 8 normally hearing subjects at the stimulus intensity corresponding to their LDL and at stimulus levels from 10 to 30 dB below this. The wave V latency/intensity function did not correlate well with the LDL. However, the slope of this function did correlate to a high degree and a predictive model of LDL was derived. Identical measurements were then taken from a sample of 12 cochlear-impaired subjects with a range of audiometric profiles. Their subjective LDLs could be predicted from the wave V latency function to an accuracy of +/- 5 dB, using the model derived from the normally-hearing subjects. This model appeared to be equally valid for all the degrees and profiles of hearing loss included in the sample and showed a closer relationship to LDL than did absolute wave V latency or estimates derived from the acoustic reflex.

Myocutaneous fenestration in sleep apnea patients

We present a patient with severe obstructive sleep apnea syndrome (OSAS), including O2 desaturations to 11%, who was successfully managed with myocutaneous fenestration tracheostomy. The myocutaneous fenestration technique employs bilateral horizontal skin-platysma advancement flaps sutured directly to a tracheal fenestra created between rings two to four. It conforms ideally to the unique physical and psychological demands of the sleep apnea patient. Rapid healing time and minimal granulation tissue, combined with a permanently functional, yet reversible and minimally disfigurative stoma, highlight the advantages of the technique over standard tracheostomy. The myocutaneous fenestration tracheostomy is uniquely applicable to the surgical treatment of patients with moderate to severe obstructive sleep apnea.

Halothane hepatitis. Detection of a constitutional susceptibility factor

We studied susceptibility to halothane hepatitis with an in vitro test that detects cell damage from electrophilic drug intermediates. Metabolites of phenytoin were generated by incubation of phenytoin with rat hepatic microsomes in the presence of the epoxide hydrolase inhibitor 1,1,1-trichloropropene oxide (TCPO), which prevents the further metabolism of phenytoin to an inert metabolite. In lymphocytes exposed to this system, cytotoxicity was measured by trypan blue dye exclusion and was expressed as the percentage increase in trypan blue-positive cells after the addition of TCPO. In the presence of TCPO, lymphocytes from 11 patients with halothane hepatitis exhibited an increase in cytotoxicity at 0.06 mM phenytoin that was eight times greater than the increase in healthy controls (54 +/- 10 per cent [mean +/- S.E.M.] vs. 7.1 +/- 2.2 per cent, P less than 0.0001). Patients with other liver diseases and persons recently exposed to halothane without adverse effects did not differ from healthy controls. In three patients with halothane hepatitis who were studied serially, the lymphocyte abnormality was still present after 13 months. Family studies revealed abnormal results on 10 cytotoxicity tests among 19 members of four families. We propose that there is a familial, constitutional susceptibility factor that predisposes persons to halothane hepatitis.