EMG Testing throughout behavioral recovery after rat sciatic nerve crush injury results in exuberant motoneuron dendritic hypertrophy

Background

Peripheral nerve injury (PNI) is the most common type of nerve trauma yet, while injured motoneurons exhibit a robust capacity for regeneration, behavioral recovery is protracted and typically poor. Neurotherapeutic approaches to PNI and repair have primarily focused on the enhancement of axonal regeneration, in terms of rate, axonal sprouting, and reconnection connectivity. Both electrical stimulation (ES) and treatment with androgens [e.g., testosterone propionate (TP)] have been demonstrated to enhance axonal sprouting, regeneration rate and functional recovery following PNI. To date, very little work has been done to examine the effects of ES and/or TP on dendritic morphology and organization within the spinal cord after PNI.

Objective

The objective of the current study was to examine the impact of treatment with TP and ES, alone or in combination, on the dendritic arbor of spinal motoneurons after target disconnection via sciatic nerve crush injury in the rat.

Methods

Rats received a crush injury to the sciatic nerve. Following injury, some animals received either (1) no further treatment beyond implantation with empty Silastic capsules, (2) electrical nerve stimulation immediately after injury, (3) implantation with Silastic capsules filled with TP, or (4) electrical nerve stimulation immediately after injury as well as implantation with TP. All of these groups of axotomized animals also received bi-weekly electromyography (EMG) testing. Additional groups of intact untreated animals as well as a group of injured animals who received no further treatment or EMG testing were also included. Eight weeks after injury, motoneurons innervating the anterior tibialis muscle were labeled with cholera toxin-conjugated horseradish peroxidase, and dendritic arbors were reconstructed in three dimensions.

Results

After nerve crush and ES and/or TP treatment, motoneurons innervating the anterior tibialis underwent marked dendritic hypertrophy. Surprisingly, this dendritic hypertrophy occurred in all animals receiving repeated bi-weekly EMG testing, regardless of treatment. When the EMG testing was eliminated, the dendritic arbor extent and distribution after nerve crush in the treated groups did not significantly differ from intact untreated animals.

Conclusions

The ability of repeated EMG testing to so dramatically affect central plasticity following a peripheral nerve injury was unexpected. It was also unexpected that gonadal steroid hormones and/or ES, two neurotherapeutic approaches with demonstrated molecular/behavioral changes consistent with peripheral improvements in axonal repair and target reconnection, do not appear to impact central plasticity in a similar manner. The significance of peripheral EMG testing and resulting central plasticity reorganization remains to be determined.

Exploring the evidence base for Tier 3 weight management interventions for adults: a systematic review

Specialist weight management services provide a treatment option for severe obesity. The objective of the study is to review the characteristics, impact and practice implications of specialist weight management services for adults in the UK. Systematic review: EMBASE, MEDLINE and PsycINFO were searched from January 2005 to March 2016 with supplementary searches. Adults with a body mass index of ≥40 kg m^-2 , or ≥35 kg m^-2 with comorbidity or ≥30 kg m^-2 with type 2 diabetes and any study of multicomponent interventions, in any UK or Ireland setting, delivered by a specialist multidisciplinary team are the inclusion criteria. Fourteen studies in a variety of settings were included: 1 randomized controlled trial, 3 controlled and 10 observational studies. Mean baseline body mass index and age ranged from 40 to 54 kg m^-2 and from 40 to 58 years. The studies were heterogeneous making comparisons of service characteristics difficult. Multidisciplinary team composition and eligibility criteria varied; dropout rates were high (43-62%). Statistically significant reduction in mean body mass index over time ranged from -1.4 to -3.1 kg m^-2 and mean weight changes ranged from -2.2 to -12.4 kg. Completers achieving at least 5% reduction of initial body weight ranged from 32 to 51%. There was evidence for improved outcomes in diabetics. Specialist weight management services can demonstrate clinically significant weight loss and have an important role in supporting adults to manage severe and often complex forms of obesity. This review highlights important variations in provision and strongly indicates the need for further research into effective approaches to support severely obese adults.

The impact of interventions to promote healthier ready-to-eat meals (to eat in, to take away or to be delivered) sold by specific food outlets open to the general public: a systematic review

INTRODUCTION

Ready-to-eat meals sold by food outlets that are accessible to the general public are an important target for public health intervention. We conducted a systematic review to assess the impact of such interventions.

METHODS

Studies of any design and duration that included any consumer-level or food-outlet-level before-and-after data were included.

RESULTS

Thirty studies describing 34 interventions were categorized by type and coded against the Nuffield intervention ladder: restrict choice = trans fat law (n = 1), changing pre-packed children's meal content (n = 1) and food outlet award schemes (n = 2); guide choice = price increases for unhealthier choices (n = 1), incentive (contingent reward) (n = 1) and price decreases for healthier choices (n = 2); enable choice = signposting (highlighting healthier/unhealthier options) (n = 10) and telemarketing (offering support for the provision of healthier options to businesses via telephone) (n = 2); and provide information = calorie labelling law (n = 12), voluntary nutrient labelling (n = 1) and personalized receipts (n = 1). Most interventions were aimed at adults in US fast food chains and assessed customer-level outcomes. More 'intrusive' interventions that restricted or guided choice generally showed a positive impact on food-outlet-level and customer-level outcomes. However, interventions that simply provided information or enabled choice had a negligible impact.

CONCLUSION

Interventions to promote healthier ready-to-eat meals sold by food outlets should restrict choice or guide choice through incentives/disincentives. Public health policies and practice that simply involve providing information are unlikely to be effective.

Locomotor analysis identifies early compensatory changes during disease progression and subgroup classification in a mouse model of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis is a motoneuron degenerative disease that is challenging to diagnose and presents with considerable variability in survival. Early identification and enhanced understanding of symptomatic patterns could aid in diagnosis and provide an avenue for monitoring disease progression. Use of the mSOD1G93A mouse model provides control of the confounding environmental factors and genetic heterogeneity seen in amyotrophic lateral sclerosis patients, while investigating underlying disease-induced changes. In the present study, we performed a longitudinal behavioral assessment paradigm and identified an early hindlimb symptom, resembling the common gait abnormality foot drop, along with an accompanying forelimb compensatory mechanism in the mSOD1G93A mouse. Following these initial changes, mSOD1 mice displayed a temporary hindlimb compensatory mechanism resembling an exaggerated steppage gait. As the disease progressed, these compensatory mechanisms were not sufficient to sustain fundamental locomotor parameters and more severe deficits appeared. We next applied these initial findings to investigate the inherent variability in B6SJL mSOD1G93A survival. We identified four behavioral variables that, when combined in a cluster analysis, identified two subpopulations with different disease progression rates: a fast progression group and a slow progression group. This behavioral assessment paradigm, with its analytical approaches, provides a method for monitoring disease progression and detecting mSOD1 subgroups with different disease severities. This affords researchers an opportunity to search for genetic modifiers or other factors that likely enhance or slow disease progression. Such factors are possible therapeutic targets with the potential to slow disease progression and provide insight into the underlying pathology and disease mechanisms.

Electrical stimulation and testosterone enhance recovery from recurrent laryngeal nerve crush

OBJECTIVE

This study investigated the effects of a combinatorial treatment, consisting of a brief period of nerve electrical stimulation (ES) and systemic supraphysiologic testosterone, on functional recovery following a crush of the recurrent laryngeal nerve (RLN).

STUDY DESIGN

Prospective, controlled animal study.

METHODS

After a crush of the left RLN, adult male Sprague-Dawley rats were divided into four treatment groups: 1) no treatment, 2) ES, 3) testosterone propionate (TP), and 4) ES + TP. Each group was subdivided into 1, 2, 3, or 4 weeks post-operative survival time points. Groups had an n of 4- 9. Recovery of vocal fold mobility (VFM) was assessed.

RESULTS

Brief ES of the proximal nerve alone or in combination with TP accelerated the initiation of functional recovery. TP administration by itself also produced increased VFM scores compared to controls, but there were no statistical differences between the ES-treated and TP-treated animals. Treatment with brief ES alone was sufficient to decrease the time required to recover complete VFM. Animals with complete VFM were seen in treatment groups as early as 1 week following injury; in the untreated group, this was not observed until at least 3 weeks post-injury, translating into a 66% decrease in time to complete recovery.

CONCLUSIONS

Brief ES, alone or in combination with TP, promise to be effective therapeutic interventions for promoting regeneration following RLN injury.

Identification of B6SJL mSOD1(G93A) mouse subgroups with different disease progression rates

Disease progression rates among patients with amyotrophic lateral sclerosis (ALS) vary greatly. Although the majority of affected individuals survive 3-5 years following diagnosis, some subgroups experience a more rapidly progressing form, surviving less than 1 year, and other subgroups experience slowly progressing forms, surviving nearly 50 years. Genetic heterogeneity and environmental factors pose significant barriers in investigating patient progression rates. Similar to the case for humans, variation in survival within the mSOD1 mouse has been well documented, but different progression rates have not been investigated. The present study identifies two subgroups of B6SJL mSOD1(G93A) mice with different disease progression rates, a fast progression group (FPG) and slow progression group, as evidenced by differences in the rate of motor function decline. In addition, increased disease-associated gene expression within the FPG facial motor nucleus confirmed the presence of a more severe phenotype. We hypothesize that a more severe disease phenotype could be the result of 1) an earlier onset of axonal disconnection with a consistent degeneration rate or 2) a more severe or accelerated degenerative process. We performed a facial nerve transection axotomy in both mSOD1 subgroups prior to disease onset as a method to standardize the axonal disconnection. Instead of leading to comparable gene expression in both subgroups, this standardization did not eliminate the severe phenotype in the FPG facial nucleus, suggesting that the FPG phenotype is the result of a more severe or accelerated degenerative process. We theorize that these mSOD1 subgroups are representative of the rapid and slow disease phenotypes often experienced in ALS.

The need for speed in rodent locomotion analyses

Locomotion analysis is now widely used across many animal species to understand the motor defects in disease, functional recovery following neural injury, and the effectiveness of various treatments. More recently, rodent locomotion analysis has become an increasingly popular method in a diverse range of research. Speed is an inseparable aspect of locomotion that is still not fully understood, and its effects are often not properly incorporated while analyzing data. In this hybrid manuscript, we accomplish three things: (1) review the interaction between speed and locomotion variables in rodent studies, (2) comprehensively analyze the relationship between speed and 162 locomotion variables in a group of 16 wild-type mice using the CatWalk gait analysis system, and (3) develop and test a statistical method in which locomotion variables are analyzed and reported in the context of speed. Notable results include the following: (1) over 90% of variables, reported by CatWalk, were dependent on speed with an average R(2) value of 0.624, (2) most variables were related to speed in a nonlinear manner, (3) current methods of controlling for speed are insufficient, and (4) the linear mixed model is an appropriate and effective statistical method for locomotion analyses that is inclusive of speed-dependent relationships. Given the pervasive dependency of locomotion variables on speed, we maintain that valid conclusions from locomotion analyses cannot be made unless they are analyzed and reported within the context of speed.

Androgen treatment and recovery of function following recurrent laryngeal nerve injury in the rat

PURPOSE

To investigate the effects of the androgen testosterone propionate (TP), on regeneration of the recurrent laryngeal nerve (RLN) after unilateral crush injury using assessment of vocal fold mobility (VFM) as a measure of behavioral recovery.

METHODS

48 adult male rats underwent standardized crush injury of left RLN and received treatment in the form of 2 silastic capsules containing TP or controls receiving a blank capsule (untreated). Direct laryngoscopic assessment of vocal cord mobility was performed before, immediately following and 1, 2, 3, 4, 5 or 6 weeks post injury.

RESULTS

Treatment with TP enhanced the recovery of full VFM following crush injury of the RLN compared to controls. There was statistically significant improvement in VFM seen at the 1 and 2 week time points (p < 0.05). By 4 weeks TP-treated rats displayed a 100% recovery of VFM function, compared to only 50% by the control group.

CONCLUSIONS

TP enhances RLN functional recovery following a crush injury, which further supports its potential general applicability as a therapeutic agent in peripheral nerve injury.

Long-term outcome of the use of botulinum toxin injection for functional anal pain

AIM

Anal pain may occur in the absence of demonstrable anal pathology. Spasm of the sphincter muscles has been suggested as a cause in some patients. We aimed to assess the effectiveness of injection of botulinum toxin in treating this condition.

METHOD

Patients who had injection of botulinum toxin over a 3-year period were identified retrospectively. Patients were excluded if anal fissure or other organic pathology was found to account for their symptoms on examination under anaesthetic. Long-term outcome was assessed at a minimum 3-year post-procedure telephone follow up.

RESULTS

Fourteen (eight male) patients were identified, of median age 50 years. Botulinum toxin (20-200 u) was injected into the internal sphincter. Seven of the 14 patients reported significant improvement in symptoms at 3 months. Seven were available for a structured telephone review at a median of 59 (42-68) months. The four patients who had benefited from the injection had remained asymptomatic.

CONCLUSION

Injection of botulinum toxin into the internal anal sphincter has a role in alleviating symptoms in a small proportion of patients with functional anal pain.

Typing Mycobacterium tuberculosis using variable number tandem repeat analysis

DNA-based typing has contributed to the understanding of M. tuberculosis epidemiology and evolution. IS6110 RFLP was the first method described and has been used in many epidemiologic investigations. Technological difficulties have hampered the widespread establishment of this method, and it has been found to be of little use in evolutionary studies. PCR-based methods such as spoligotyping and variable number tandem repeat (VNTR) analysis largely overcome these difficulties. Spoligotyping alone is of limited value in epidemiologic investigations due to low discrimination but can be useful in evolutionary studies. Panels of VNTR loci selected from the 59 polymorphic VNTRs described to date have been shown to be useful in both epidemiologic and evolutionary studies. A VNTR type is identified by, first, amplifying a series of PCR fragments each encompassing a different VNTR locus and, second, determining the PCR fragment sizes from which the number of repeats present is calculated. The repeat number present at a series of loci is used as numerical code to describe a type. This chapter describes a high-throughput automated method for VNTR analysis at 15 loci using a capillary fragment analyzer and a manual method using agarose gel analysis.

The impact of maternal BMI status on pregnancy outcomes with immediate short-term obstetric resource implications: a meta-analysis

Obesity is rising in the obstetric population, yet there is an absence of services and guidance for the management of maternal obesity. This systematic review aimed to investigate relationships between obesity and impact on obstetric care. Literature was systematically searched for cohort studies of pregnant women with anthropometric measurements recorded within 16-weeks gestation, followed up for the term of the pregnancy, with at least one obese and one comparison group. Two researchers independently data-extracted and quality-assessed each included study. Outcome measures were those that directly or indirectly impacted on maternity resources. Primary outcomes included instrumental delivery, caesarean delivery, duration of hospital stay, neonatal intensive care, neonatal trauma, haemorrhage, infection and 3rd/4th degree tears. Meta-analysis shows a significant relationship between obesity and increased odds of caesarean and instrumental deliveries, haemorrhage, infection, longer duration of hospital stay and increased neonatal intensive care requirement. Maternal obesity significantly contributes to a poorer prognosis for mother and baby during delivery and in the immediate post-partum period. National clinical guidelines for management of obese pregnant women, and public health interventions to help safeguard the health of mothers and their babies are urgently required.

Trends in colorectal day case surgery in NHS Trusts between 1998 and 2005

OBJECTIVE

Day case surgery is safe and offers potential benefits to both patients and healthcare providers. This study aimed to describe national changes in colorectal day case workload between 1998 and 2005.

METHODS

Admission data relating to Office of Population Censuses and Surveys Classification of Surgical Operations and Procedures (4th revision) (OPCS-4) coloproctology operation codes were analysed using the Hospital Episode Statistics (HES) database. Day case rates (DCRs) were calculated as the proportion of elective cases performed on an ambulatory basis.

RESULTS

In total, 3 119 058 colorectal admissions were recorded on the HES database between 1998 and 2005; 1 891 474 (61%) of these were for lower gastrointestinal endoscopies. Emergency cases accounted for 527 665 (17%), elective inpatient cases for 406 368 (13%) and elective day cases for 293 551 (9%) admissions. Throughout the study period the DCRs for five commonly performed elective colorectal procedures were: 0.70 for anal lesion excisions (OPCS-4 codes: H48.1, H48.2 and H48.3); 0.16 for haemorrhoidectomy (OPCS-4 code: H51.1); 0.63 for anal fissure procedures (OPCS-4 codes: H56.2 and H56.4); 0.39 for elective procedures for anal fistula (OPCS-4 codes: H55.1, H55.2, H55.3 and H55.4); 0.37 for elective pilonidal surgery (OPCS-4 codes: H59 and H60.2). Two emergency operations, drainage of perianal and pilonidal abscesses (OPCS-4 codes: H58.2 and H60.3 respectively), were identified as operations potentially amenable to day surgery. Over the seven study years, an annual average of 8559 (+/-SD 307) admissions were coded to drainage of a perianal abscess and 4676 (+/-SD 478) admissions to drainage of pilonidal abscess. The average annual bed usage associated with these procedures was 18 831 (+/-SD 718) and 7623 (+/-SD 436) bed days respectively.

CONCLUSIONS

Colorectal day case surgery is currently under-exploited in the NHS. By lifting some of the barriers to day case surgery significant resource savings may be possible.

Phagocytosis of collagen by fibroblasts and invasive cancer cells is mediated by MT1-MMP

Degradation of collagen is required for the physiological remodelling of connective tissues during growth and development, as well as in wound healing, inflammatory diseases, and cancer cell invasion. In remodelling adult tissues, degradation of collagen occurs primarily through a phagocytic pathway. While various steps in this pathway have been characterized, the enzyme required to fragment collagen fibrils for phagocytosis has not been identified. Laser confocal microscopy, transmission electron microscopy and biochemical assays were used to show that degradation of collagen substrates by fibroblasts correlated with the expression of the membrane-bound metalloproteinase MT1-MMP (membrane-type 1 matrix metalloproteinase). The MT1-MMP was localized to sites of collagen cleavage on the cell surface and also within the cells. In contrast with MT1-MMP, the gelatinase MMP-2 was not required for collagen phagocytosis. Similar analyses of several ovarian cancer, breast cancer and fibrosarcoma cells indicated that highly metastatic cells also degrade collagen through a phagocytic pathway that is mediated by MT1-MMP. Collectively, these studies demonstrate a pivotal role for catalytically active MT1-MMP in preparing collagen fibrils for phagocytic degradation by normal and transformed cells.

MT1-MMP is the critical determinant of matrix degradation and invasion by ovarian cancer cells

Membrane-type 1 matrix metalloproteinase (MT1-MMP), a transmembrane metalloprotease that plays an important role in the invasion of many solid tumour types, promotes pericellular matrix degradation and may also stimulate tumour cell motility. As both these processes are key contributors to intraperitoneal ovarian tumour metastasis, we examined six ovarian cancer cell lines to determine whether MT1 is a critical mediator of invasive behaviour for this tumour type. Our results indicated that only those cell lines that expressed MT1 were capable of penetrating a type I collagen barrier, with the capacity for both matrix degradation and invasion reflecting endogenous MT1 expression level. Ectopic MT1 expression endowed an invasive phenotype upon cell lines lacking MT1 that were previously non-invasive, indicating the crucial role of this protease. Conversely, invasion was abolished by tissue inhibitor of metalloproteinase-2 (TIMP-2), a potent inhibitor of MT1, yet was minimally affected when other (secreted) MMPs were inhibited using TIMP-1 and the gelatinase inhibitor SB-3CT. Whereas collagen I degradation was strikingly accelerated by ectopic MT1 expression, cell motility remained unchanged. We conclude that MT1 is necessary for collagen I invasion by ovarian cancer cells, and that its requisite activity is the promotion of matrix degradation, with no impact on cell motility.

Cost-effectiveness of cell salvage and alternative methods of minimising perioperative allogeneic blood transfusion: a systematic review and economic model

OBJECTIVES

To compare patient outcomes, resource use and costs to the NHS and NHS Blood Transfusion Authority (BTA) associated with cell salvage and alternative methods of minimising perioperative allogeneic blood transfusion.

DATA SOURCES

Electronic databases covering the period 1996-2004 for systematic reviews and 1994-2004 for economic evidence.

REVIEW METHODS

Existing systematic reviews were updated with data from selected randomised controlled trials (RCTs) that involved adults scheduled for elective non-urgent surgery. Any resource use or cost data were extracted for potential use in populating an economic model. Relative risks or weighted mean difference of each outcome for each intervention were assessed, taking into account the number of RCTs included in each outcome and intervention and the presence of any heterogeneity. This allowed indirect comparison of the relative effectiveness of each intervention when the intervention is compared with allogeneic blood transfusion. A decision analytic model synthesised clinical and economic data from several sources, to estimate the relative cost-effectiveness of cell salvage for people undergoing elective surgery with moderate to major expected blood loss. The perspective of the NHS and patients and a time horizon of 1 month were used. The economic model was developed from reviews of effectiveness and cost-effectiveness and clinical experts. Secondary analysis explored the robustness of the results to changes in the timing and costs of cell salvage equipment, surgical procedure, use of transfusion protocols and time horizon of analysis.

RESULTS

Overall, 668 studies were identified electronically for the update of the two systematic reviews. This included five RCTs, of which two were cell salvage and three preoperative autologous donation (PAD). Five published systematic reviews were identified for antifibrinolytics, fibrin sealants and restrictive transfusion triggers, PAD plus erythropoietin, erythropoietin alone and acute normovolaemic haemodilution (ANH). Twelve published studies reported full economic evaluations. All but two of the transfusion strategies significantly reduced exposure to allogeneic blood. The relative risk of exposure to allogeneic blood was 0.59 for the pooled trials of cell salvage (95% confidence interval: 0.48 to 0.73). This varied by the type and timing of cell salvage and type of surgical procedure. For cell salvage, the relative risk of allogeneic blood transfusion was higher in cardiac surgery than in orthopaedic surgery. Cell salvage had lower costs and slightly higher quality-adjusted life years compared with all of the alternative transfusion strategies except ANH. The likelihood that cell salvage is cost-effective compared with strategies other than ANH is over 50%. Most of the secondary analyses indicated similar results to the primary analysis. However, the primary and secondary analyses indicated that ANH may be more cost-effective than cell salvage.

CONCLUSIONS

The available evidence indicates that cell salvage may be a cost-effective method to reduce exposure to allogeneic blood transfusion. However, ANH may be more cost-effective than cell salvage. The results of this analysis are subject to the low quality and reliability of the data used and the use of indirect comparisons. This may affect the reliability and robustness of the clinical and economic results. There is a need for further research that includes adequately powered high-quality RCTs to compare directly various blood transfusion strategies. These should include measures of health status, health-related quality of life and patient preferences for alternative transfusion strategies. Observational and tracking studies are needed to estimate reliably the incidence of adverse events and infections transmitted during blood transfusion and to identify the lifetime consequences of the serious hazards of transfusion on mortality, health status and health-related quality of life.

Molecular epidemiology and prevalence of mutations conferring rifampicin and isoniazid resistance in Mycobacterium tuberculosis strains from the southern Ukraine

Understanding the molecular epidemiology of tuberculosis (TB) and mutations in genes associated with drug resistance may contribute to the development of appropriate interventions to improve tuberculosis control. A structured questionnaire was used to collect basic epidemiological data from 589 patients with radiologically confirmed TB in the Odessa and Nikolaev regions of the Ukraine in 2003-2004. A non-commercial reverse hybridisation assay and DNA sequencing were used to detect mutations associated with rifampicin and isoniazid resistance. Genotyping was performed using multilocus variable number tandem repeat (VNTR) typing and spoligotyping. Mutations conferring rifampicin and isoniazid resistance were detected in 32.9% and 44.0%, respectively, of 225 Mycobacterium tuberculosis isolates from individual consecutive patients. Mutations in codon 531 and codon 315 of the rpoB and katG genes, respectively, were predominant among drug-resistant isolates. Multidrug (MDR) resistance rates were significantly higher among former prison inmates compared with non-prisoners (54.8% vs. 27.3%; RR 2.01; 95% CI 1.35-2.97) and the prevalence of mutations was higher in Beijing strains sharing the VNTR signature 223325173533424 than in other Beijing strains (71.4% vs. 45.7%; RR 1.74; 95% CI 1.17-2.57), suggesting that this group may be responsible for rapid transmission of MDR TB in the southern Ukraine.

A comparison of the cost-effectiveness of five strategies for the prevention of non-steroidal anti-inflammatory drug-induced gastrointestinal toxicity: a systematic review with economic modelling

OBJECTIVES

To assess the relative effectiveness, patient acceptability, costs and cost-effectiveness of four strategies for the prevention of non-steroidal anti-inflammatory drugs (NSAIDs)-induced gastrointestinal (GI) toxicity: (1) Cox-1 NSAIDs plus histamine-2 receptor antagonist (H2RA), (2) Cox-1 NSAIDs plus proton pump inhibitors (PPIs), (3) Cox-1 NSAIDs plus misoprostol, and (4) Cox-2 NSAIDs (later expanded to 4a Cox-2 coxibNSAIDs and 4b Cox-2 preferential NSAIDs).

DATA SOURCES

Electronic databases up to May 2002.

REVIEW METHODS

Relevant studies were selected, assessed and analysed. Pooled relative risk ratios (RR) from the systematic review were combined with up-to-date UK resource use and unit costs data in an incremental economic analysis. A probabilistic decision-analytic model was designed and populated with data to carry out incremental economic analysis. Incremental cost-effectiveness ratios (ICERs) were generated for the outcome measure, endoscopic ulcer or serious GI event averted, against total cost, and non-parametric bootstrapping was used to simulate variance of these ICERs.

RESULTS

Of 118 selected trials, including 125 relevant comparisons (which included 76,322 participants) only 138 deaths and 248 serious GI events were reported. Seven comparisons were judged to be at low risk of bias. Comparing the gastroprotective strategies against placebo, there was no evidence of effectiveness of H2RAs against any primary outcomes (few events reported), PPIs may reduce the risk of symptomatic ulcers [RR 0.09, 95% confidence interval (CI) 0.02 to 0.47], misoprostol reduces the risk of serious GI complications (RR 0.57, 95% CI 0.36 to 0.91) and symptomatic ulcers (RR 0.36, 95% CI 0.20 to 0.67), Cox-2 'preferentials' reduce the risk of symptomatic ulcers (RR 0.41, 95% CI 0.26 to 0.65) and Cox-2 'coxibs' reduce the risk of symptomatic ulcers (RR 0.49, 95% CI 0.38 to 0.62) and possibly serious GI events (RR 0.55, 95% CI 0.38 to 0.80). All strategies except Cox-2 'preferentials' reduce the risk of endoscopic ulcers. There were only 12 direct comparisons between gastroprotective strategies. All they suggest is that Cox-2 preferentials are better than misoprostol for preventing GI complications. Indirect comparisons suggested that PPIs may prevent symptomatic ulcers better than Cox-2 coxibs, but this is very weak evidence. For prevention of endoscopic ulcers PPIs and misoprostol appear more successful than H2RAs and misoprostol is better than Cox-2 preferentials. There were no UK head-to-head published economic analyses with regard to the main gastroprotective strategies. There were generally insufficient data with regards to cardiac or renal outcomes, serious GI outcomes or life-years gained to populate the mode. Mean (2.5th and 97.5th percentile) costs per endoscopic ulcer averted compared with Cox-1 NSAIDs alone were as follows: Cox-1 plus H2RAs, -186 pounds (-555 to 804); Cox-1 plus PPIs, 454 pounds (251 to 877); Cox-1 plus misoprostol, 54 pounds (-112 to 238); Cox-2 selective NSAIDs, 263 pounds (-570 to 1280), or Cox-2 specific NSAIDs, 301 pounds (189 to 418). With regard to the prevention of endoscopic ulcers, Cox-1 NSAID plus H2RA is a dominant option. Cost-effectiveness acceptability analysis showed a 95% probability that this combination was less costly and more effective. Cost-effectiveness acceptability frontiers showed that if the decision-maker is willing to pay up to 750 pounds to avoid an endoscopic ulcer, then Cox-1 plus H2RA is the optimal strategy. If the decision-maker is willing to pay over 750 pounds, the optimal strategy is NSAID plus misoprostol. Between 1900 pounds and 3750 pounds, Cox-2 selective inhibitors are optimal, and over 3750 pounds, Cox-2 specific inhibitors become optimal. NSAID plus PPI is never the optimal strategy. Sensitivity and subgroup analyses suggest that Cox-1 NSAID plus H2RA and Cox-1 NSAID plus misoprostol become more cost-effective in the older age group. Some conclusions were associated with high levels of uncertainty.

CONCLUSIONS

Although there is a very large body of evidence comparing Cox-2 NSAIDs with Cox-1 NSAIDs, this is not matched by studies of the other types of gastroprotectors or by studies directly comparing active gastroprotective strategies. This lack of direct comparisons led to the use of indirect comparisons to help understand the relative efficacy of these strategies. Indirect evidence in itself is weak and was also hampered by lack of evidence in the underlying studies (where the gastroprotectors were compared with placebo). Economic modelling suggests that Cox-1 NSAID plus H2RA or Cox-1 NSAID plus PPI are the most cost-effective strategies for avoiding endoscopic ulcers in patients requiring long-term NSAID therapy. All strategies other than Cox-2 selective inhibitors reduce the rate of endoscopic ulcer compared with Cox-1 alone. The economic analysis suggests that there may be a case for prescribing H2RAs in all patients requiring NSAIDs. Misoprostol is more effective, but is associated with a greater cost and GI side-effects which may be unacceptable for patients. However, when assessing serious GI events, the economic analysis is sufficiently weakened by the data available as to render clear practice recommendations impossible. Further large, independent RCTs directly comparing various gastroprotective strategies are needed. These should report items such as major outcomes, primary data, adverse events, assessment of practice and patient preference.

Differentially androgen-modulated genes in ovarian epithelial cells from BRCA mutation carriers and control patients predict ovarian cancer survival and disease progression

Epidemiological studies have implicated androgens in the etiology and progression of epithelial ovarian cancer. We previously reported that some androgen responses were dysregulated in malignant ovarian epithelial cells relative to control, non-malignant ovarian surface epithelial (OSE) cells. Moreover, dysregulated androgen responses were observed in OSE cells derived from patients with germline BRCA-1 or -2 mutations (OSEb), which account for the majority of familial ovarian cancer predisposition, and such altered responses may be involved in ovarian carcinogenesis or progression. In the present study, gene expression profiling using cDNA microarrays identified 17 genes differentially expressed in response to continuous androgen exposure in OSEb cells and ovarian cancer cells as compared to OSE cells derived from control patients. A subset of these differentially affected genes was selected and verified by quantitative real-time reverse transcription-polymerase chain reaction. Six of the gene products mapped to the OPHID protein-protein interaction database, and five were networked within two interacting partners. Basic leucine zipper transcription factor 2 (BACH2) and acetylcholinesterase (ACHE), which were upregulated by androgen in OSEb cells relative to OSE cells, were further investigated using an ovarian cancer tissue microarray from a separate set of 149 clinical samples. Both cytoplasmic ACHE and BACH2 immunostaining were significantly increased in ovarian cancer relative to benign cases. High levels of cytoplasmic ACHE staining correlated with decreased survival, whereas nuclear BACH2 staining correlated with decreased time to disease recurrence. The finding that products of genes differentially responsive to androgen in OSEb cells may predict survival and disease progression supports a role for altered androgen effects in ovarian cancer. In addition to BACH2 and ACHE, this study highlights a set of potentially functionally related genes for further investigation in ovarian cancer.

The use of macroarrays for the identification of MDR Mycobacterium tuberculosis

The emergence of Mycobacterium tuberculosis (Mtb), resistant to both isoniazid (INH) and rifampicin (RIF) (MDR-TB), is an increasing threat to tuberculosis control programs. Susceptibility testing of Mtb complex isolates by phenotypic methods requires a minimum of 14 days from a primary specimen. This can be reduced significantly if molecular analysis is used. Low density oligonucleotide arrays (macroarrays) have been used successfully for the detection of RIF resistance in Mtb. We describe the use of macroarray technology to identify Mtb complex isolates resistant to INH and/or RIF. The macroarray MDR-Mtb screen has been designed to detect mutations in the RIF resistance determining region (RRDR) of Mtb rpoB and loci in katG and mabA-inhA associated with INH resistance. A panel of Mtb isolates containing 38 different RRDR genotypes, 4 different genotypes within codon 315 of katG and 2 genotypes at mabA-inhA was used to validate the macroarray. The wild type (WT) genotype was correctly identified at all three loci. Of the 37 mutant rpoB genotypes, 36 were correctly detected; the single mutant not detected contained a 9 base insertion. All mutations within katG and mabA-inhA were correctly identified. We conclude that this low cost, rapid system can usefully detect the mutations associated with the vast majority of MDR-Mtb.

Preventing non-steroidal anti-inflammatory drug-induced gastrointestinal toxicity: are older strategies more cost-effective in the general population?

OBJECTIVES

To assess the relative cost-effectiveness of five gastroprotective strategies for patients in the general population not judged to be at high gastrointestinal (GI) risk requiring regular traditional (t) non-steroidal anti-inflammatory drugs (NSAIDs) for over 3 weeks: tNSAID/H(2) receptor antagonists (H(2)RAs); tNSAID/proton pump inhibitors (PPIs); tNSAID/misoprostol; COX-2 preferential NSAIDs or COX-2-specific NSAIDs (COXIBs).

METHODS

A systematic review of outcomes and UK cost data were combined in an incremental economic analysis. Incremental cost-effectiveness ratios were generated for quality-adjusted life years (QALYs) gained.

RESULTS

Cost-utility analysis showed a tNSAID with a H(2)RA is safer and less costly than tNSAIDs alone, and equally effective and less costly than COXIBs. tNSAID/misoprostol was also dominated by tNSAID/H(2)RA due to withdrawal caused by side-effects reducing overall health status. The incremental increase in QALYs gained by using COXIBs instead of tNSAID/H(2)RA would cost 670,000 pounds per QALY gained. The incremental increase in QALYs gained by using tNSAID/PPI instead of COXIBs would cost 26,000 pounds per QALY gained. If the decision-maker will pay up to 140,000 pounds per extra QALY, the optimal strategy is tNSAID/H(2)RA. If the decision-maker will pay over this the optimal strategy is tNSAID/PPI.

CONCLUSION

The economic analysis suggests that there may be a case for prescribing H(2)RAs in all patients requiring NSAIDs. Our recommendations are tentative due to the quality of the data available and the assumptions we have had to make in our model, and it is possible that other strategies may be preferred in patients with higher baseline GI risk.

Molecular analysis of isoniazid-resistant Mycobacterium tuberculosis isolates from England and Wales reveals the phylogenetic significance of the ahpC -46A polymorphism

The present study investigated the prevalence and diagnostic potential of the most commonly reported mutations associated with isoniazid resistance, katG 315Thr, katG 315Asn, inhA -15T, inhA -8A, and the oxyR-ahpC intergenic region, in a population sample of 202 isoniazid-resistant Mycobacterium tuberculosis isolates and 176 randomly selected fully sensitive isolates from England and Wales identified by using a directed oligonucleotide array and limited DNA sequencing. The strains were recovered from patients originating from 29 countries; 41 isolates were multidrug resistant. Mutations affecting katG 315, the inhA promoter, and the oxyR-ahpC intergenic region were found in 62.7, 21.9, and 30% of 169 genotypically distinct isoniazid-resistant isolates, respectively, whereas they were found in 0, 0, and 8% of susceptible strains, respectively. The frequency of mutation at each locus was unrelated to the resistance profile or previous antituberculous drug therapy. The commonest mutation in the oxyR-ahpC intergenic region, ahpC -46A, was present in 23.7% of isoniazid-resistant isolates and 7.5% of susceptible isolates. This proved to be a phylogenetic marker for a subgroup of M. tuberculosis strains originating on the Indian subcontinent, which shared IS6110-based restriction fragment length polymorphism and spoligotype features with the Delhi strain and Central Asian strain CAS1; and this marker is strongly associated with isoniazid resistance and the katG 315Thr mutation. In total, 82.8% of unrelated isoniazid-resistant isolates could be identified by analysis of just two loci: katG 315 and the inhA promoter. Analysis of the oxyR-ahpC intergenic region, although phylogenetically interesting, does not contribute significantly to further identification of isoniazid-resistant isolates.