Advancements in diabetic kidney disease management: integrating innovative therapies and targeted drug development

Diabetic kidney disease (DKD) is a leading cause of chronic kidney disease and affects approximately 40% of individuals with diabetes . Cases of DKD continue to rise globally as the prevalence of diabetes mellitus increases, with an estimated 415 million people living with diabetes in 2015 and a projected 642 million by 2040. DKD is associated with significant morbidity and mortality, representing 34% and 36% of all chronic kidney disease deaths in men and women, respectively. Common comorbidities including hypertension and ageing-related nephron loss further complicate disease diagnosis and progression. The progression of DKD involves several mechanisms including glomerular endothelial cell dysfunction, inflammation, and fibrosis. Targeting these mechanisms has formed the basis of several therapeutic agents. Renin-angiotensin-aldosterone system (RAAS) blockers, specifically angiotensin receptor blockers (ARBs), demonstrate significant reductions in macroalbuminuria. Sodium-glucose transporter type 2 (SGLT-2) inhibitors demonstrate kidney protection independent of diabetes control while also decreasing the incidence of cardiovascular events. Emerging agents including glucagon-like peptide 1 (GLP-1) agonists, anti-inflammatory agents like bardoxolone, and mineralocorticoid receptor antagonists show promise in mitigating DKD progression. Many novel therapies including monoclonal antibodies CSL346, lixudebart, and tozorakimab; mesenchymal stem/stromal cell infusion; and cannabinoid-1 receptor inverse agonism via INV-202 are currently in clinical trials and present opportunities for further drug development.

Enhancing European capabilities for application of multi-omics studies in biology and biomedicine space research

Following on from the NASA twins' study, there has been a tremendous interest in the use of omics techniques in spaceflight. Individual space agencies, NASA's GeneLab, JAXA's ibSLS, and the ESA-funded Space Omics Topical Team and the International Standards for Space Omics Processing (ISSOP) groups have established several initiatives to support this growth. Here, we present recommendations from the Space Omics Topical Team to promote standard application of space omics in Europe. We focus on four main themes: i) continued participation in and coordination with international omics endeavors, ii) strengthening of the European space omics infrastructure including workforce and facilities, iii) capitalizing on the emerging opportunities in the commercial space sector, and iv) capitalizing on the emerging opportunities in human subjects research.

Transcriptome Profiling Reveals Enhanced Mitochondrial Activity as a Cold Adaptive Strategy to Hypothermia in Zebrafish Muscle

The utilisation of synthetic torpor for interplanetary travel once seemed farfetched. However, mounting evidence points to torpor-induced protective benefits from the main hazards of space travel, namely, exposure to radiation and microgravity. To determine the radio-protective effects of an induced torpor-like state we exploited the ectothermic nature of the Danio rerio (zebrafish) in reducing their body temperatures to replicate the hypothermic states seen during natural torpor. We also administered melatonin as a sedative to reduce physical activity. Zebrafish were then exposed to low-dose radiation (0.3 Gy) to simulate radiation exposure on long-term space missions. Transcriptomic analysis found that radiation exposure led to an upregulation of inflammatory and immune signatures and a differentiation and regeneration phenotype driven by STAT3 and MYOD1 transcription factors. In addition, DNA repair processes were downregulated in the muscle two days' post-irradiation. The effects of hypothermia led to an increase in mitochondrial translation including genes involved in oxidative phosphorylation and a downregulation of extracellular matrix and developmental genes. Upon radiation exposure, increases in endoplasmic reticulum stress genes were observed in a torpor+radiation group with downregulation of immune-related and ECM genes. Exposing hypothermic zebrafish to radiation also resulted in a downregulation of ECM and developmental genes however, immune/inflammatory related pathways were downregulated in contrast to that observed in the radiation only group. A cross-species comparison was performed with the muscle of hibernating Ursus arctos horribilis (brown bear) to define shared mechanisms of cold tolerance. Shared responses show an upregulation of protein translation and metabolism of amino acids, as well as a hypoxia response with the shared downregulation of glycolysis, ECM, and developmental genes.

Investigating the effects of chronic low-dose radiation exposure in the liver of a hypothermic zebrafish model

Mankind's quest for a manned mission to Mars is placing increased emphasis on the development of innovative radio-protective countermeasures for long-term space travel. Hibernation confers radio-protective effects in hibernating animals, and this has led to the investigation of synthetic torpor to mitigate the deleterious effects of chronic low-dose-rate radiation exposure. Here we describe an induced torpor model we developed using the zebrafish. We explored the effects of radiation exposure on this model with a focus on the liver. Transcriptomic and behavioural analyses were performed. Radiation exposure resulted in transcriptomic perturbations in lipid metabolism and absorption, wound healing, immune response, and fibrogenic pathways. Induced torpor reduced metabolism and increased pro-survival, anti-apoptotic, and DNA repair pathways. Coupled with radiation exposure, induced torpor led to a stress response but also revealed maintenance of DNA repair mechanisms, pro-survival and anti-apoptotic signals. To further characterise our model of induced torpor, the zebrafish model was compared with hepatic transcriptomic data from hibernating grizzly bears (Ursus arctos horribilis) and active controls revealing conserved responses in gene expression associated with anti-apoptotic processes, DNA damage repair, cell survival, proliferation, and antioxidant response. Similarly, the radiation group was compared with space-flown mice revealing shared changes in lipid metabolism.

3D Intracardiac Echocardiography in Mitral Transcatheter Edge-to-Edge Repair

Intracardiac echocardiography (ICE) has historically had limited utility in complex structural interventions. Newer 3-dimensional ICE catheters have enhanced imaging and real-time functionality. We present a novel case of mitral valve transcatheter edge-to-edge repair where transesophageal imaging was limited by massive hiatal hernia and where complementary 3D ICE imaging enabled procedural success. (Level of Difficulty: Intermediate.)

Impact of regurgitant orifice ellipticity on quantitation of tricuspid regurgitation using the proximal isovelocity surface area method

Funding Acknowledgements

Type of funding sources: None.

Background

The proximal isovelocity surface area (PISA) method to quantify tricuspid regurgitation (TR) severity relies on the geometric assumption of a circular, planar regurgitant orifice.  However, the TR orifice is often non-circular resulting in underestimation of TR severity when calculating the effective regurgitant orifice area (EROA) and regurgitant volume (RegVol).

Purpose

To evaluate the effect of ellipticity of the tricuspid annulus on EROA-PISA correlation with quantitative Doppler (EROA-Dopp), and three-dimensional vena contracta area (VCA-3D).

Methods

Patients undergoing both transthoracic (TTE) and transesophageal (TEE) echo evaluation of TR severity were included in this study. Regurgitant orifice ellipticity was calculated as the ratio of the vena contracta maximum and minimum widths (VC-Ratio). Quantification of EROA and RegVol were performed on TTE for EROA-PISA and EROA-Dopp. Vena contract area was measured on TEE (VCA-3D).

Results

Of 44 total pts, the median age was 80 ± 9, 61% were female, 89% had atrial fibrillation, (86%) had functional TR, 32% were graded as severe, and 71% had a EROA-PISA ≥ 0.4 cm2. Median VC-Ratio was 1.3 (IQR 1.1-1.8) and was used to differentiate more circular orifices (VC-Ratio <1.3) from more elliptical orifices (VC-Ratio ≥1.3) (Table). EROA-PISA was significantly smaller compared to EROA-Dopp and VCA-3D in the whole group as well as elliptical subgroups (p < 0.0001 for all).  There was no significant difference between EROA-Dopp and 3D-VCA for the whole group, or in circular or elliptical orifice subgroups (p > 0.5 for all). EROA-PISA correlated better with both EROA-Dopp and VCA-3D in circular compared to elliptical orifices (Table). EROA-Dopp and VCA-3D demonstrated high correlation for both circular and elliptical orifices (r = 0.76, p < 0.0001 and r = 0.77, p < 0.0001 respectively).

Conclusion

Our study demonstrated that there is a significant difference in quantitative measurements of tricuspid regurgitant orifice area, with EROA-PISA significantly underestimating both EROA-Dopp and VCA-3D.  In more circular orifices, the EROA-PISA correlation was higher, however EROA-Dopp and VCA-3D were still significantly larger. Whether EROA-Dopp and VCA-3D are more predictive of outcomes requires further study. Abstract Table 1  Abstract Figure 1

Correlation between standard and adjusted echocardiographic quantitative methods for evaluating tricuspid regurgitation severity

Funding Acknowledgements

Type of funding sources: None.

Background

Current guidelines advocate for a multi-parametric approach to echocardiographic quantitation of tricuspid regurgitation (TR). The primary quantitative measure of TR severity uses the proximal isovelocity surface area (PISA) method to calculate effective regurgitant orifice area (EROA) and regurgitant volume (RegVol). However, EROA-PISA may underestimate TR severity due to low flow and tethering of the tricuspid leaflets.

Purpose

The purpose of this study was to compare standard EROA-PISA quantitation of TR to alternative quantitative measures, including quantitative Doppler (EROA-Doppler), flow- and angle-corrected PISA method (EROA-Corrected), and three-dimensional vena contracta area (3D-VCA), in addition to the comparison of calculated RegVol-PISA, RegVol-Doppler, and RegVol-3DVCA.

Methods

Patients undergoing both transthoracic (TTE) and transesophageal (TEE) echocardiographic evaluation of TR severity for transcatheter treatment were included in this study. Patients were excluded if they had ≥ moderate aortic regurgitation. TTE measurements of EROA-PISA and RegVol-PISA were performed as per American Society of Echocardiography guidelines. EROA-Doppler was performed by quantifying RegVol-Doppler (diastolic stroke volume using biplane annular area, minus left ventricular outflow stroke volume) and deriving EROA. EROA-Corrected was calculated by adjusting for both aliasing velocity and leaflet angle as per published methods. 3D-VCA was measured on TEE performed within 14 days of TTE.

Results

Of 44 consecutive patients, the median age was 80 ± 9 years, 61% were female, and 89% had atrial fibrillation. Most patients (86%) had functional TR, 71% had a EROA-PISA ≥ 0.4 cm2. Table 1 shows the EROA and RegVol results for each method.  EROA-PISA and RegVol-PISA were significantly lower than EROA-Doppler and RegVol-Doppler, as well as 3D-VCA and RegVol-3DVCA (all p < 0.0001). There was no significant difference between EROA-Doppler and 3D-VCA (p = 0.51), and RegVol-Doppler and RegVol-3DVCA (p = 0.66).  EROA-Corrected reduced the absolute difference with EROA-Doppler (51% to 33%, p < 0.0001) and 3D-VCA (52% to 32%, p < 0.0001), but remained statistically lower than EROA-Doppler and 3D-VCA. Although EROA-PISA was strongly correlated to EROA-Doppler (r = 0.75, p < 0.0001) and 3D-VCA (r = 0.68, p < 0.0001), the correlation between EROA-Doppler and 3D-VCA was greatest (r = 0.77, p < 0.0001). Adjusting EROA-PISA for angle and flow demonstrated improved correlation to EROA-Doppler without affecting correlation to 3D-VCA (Figure 1).

Conclusion

Our study demonstrated that EROA-PISA significantly underestimates the severity of TR by EROA-Doppler and 3D-VCA. Although PISA correction methods reduced the underestimation, both EROA-Corrected and RegVol-Corrected remained significantly lower. EROA-Doppler and 3D-VCA and the calculated RegVol by each method, were closely correlated and not significantly different. Abstract Table 1  Abstract Figure 1

Mammalian and Invertebrate Models as Complementary Tools for Gaining Mechanistic Insight on Muscle Responses to Spaceflight

Bioinformatics approaches have proven useful in understanding biological responses to spaceflight. Spaceflight experiments remain resource intensive and rare. One outstanding issue is how to maximize scientific output from a limited number of omics datasets from traditional animal models including nematodes, fruitfly, and rodents. The utility of omics data from invertebrate models in anticipating mammalian responses to spaceflight has not been fully explored. Hence, we performed comparative analyses of transcriptomes of soleus and extensor digitorum longus (EDL) in mice that underwent 37 days of spaceflight. Results indicate shared stress responses and altered circadian rhythm. EDL showed more robust growth signals and Pde2a downregulation, possibly underlying its resistance to atrophy versus soleus. Spaceflight and hindlimb unloading mice shared differential regulation of proliferation, circadian, and neuronal signaling. Shared gene regulation in muscles of humans on bedrest and space flown rodents suggest targets for mitigating muscle atrophy in space and on Earth. Spaceflight responses of C. elegans were more similar to EDL. Discrete life stages of D. melanogaster have distinct utility in anticipating EDL and soleus responses. In summary, spaceflight leads to shared and discrete molecular responses between muscle types and invertebrate models may augment mechanistic knowledge gained from rodent spaceflight and ground-based studies.

Induced Torpor as a Countermeasure for Low Dose Radiation Exposure in a Zebrafish Model

The development of the Artemis programme with the goal of returning to the moon is spurring technology advances that will eventually take humans to Mars and herald a new era of interplanetary space travel. However, long-term space travel poses unique challenges including exposure to ionising radiation from galactic cosmic rays and potential solar particle events, exposure to microgravity and specific nutritional challenges arising from earth independent exploration. Ionising radiation is one of the major obstacles facing future space travel as it can generate oxidative stress and directly damage cellular structures such as DNA, in turn causing genomic instability, telomere shortening, extracellular-matrix remodelling and persistent inflammation. In the gastrointestinal tract (GIT) this can lead to leaky gut syndrome, perforations and motility issues, which impact GIT functionality and affect nutritional status. While current countermeasures such as shielding from the spacecraft can attenuate harmful biological effects, they produce harmful secondary particles that contribute to radiation exposure. We hypothesised that induction of a torpor-like state would confer a radioprotective effect given the evidence that hibernation extends survival times in irradiated squirrels compared to active controls. To test this hypothesis, a torpor-like state was induced in zebrafish using melatonin treatment and reduced temperature, and radiation exposure was administered twice over the course of 10 days. The protective effects of induced-torpor were assessed via RNA sequencing and qPCR of mRNA extracted from the GIT. Pathway and network analysis were performed on the transcriptomic data to characterise the genomic signatures in radiation, torpor and torpor + radiation groups. Phenotypic analyses revealed that melatonin and reduced temperature successfully induced a torpor-like state in zebrafish as shown by decreased metabolism and activity levels. Genomic analyses indicated that low dose radiation caused DNA damage and oxidative stress triggering a stress response, including steroidal signalling and changes to metabolism, and cell cycle arrest. Torpor attenuated the stress response through an increase in pro-survival signals, reduced oxidative stress via the oxygen effect and detection and removal of misfolded proteins. This proof-of-concept model provides compelling initial evidence for utilizing an induced torpor-like state as a potential countermeasure for radiation exposure.

Incidence and outcomes of infective endocarditis following transcatheter aortic valve implantation

INTRODUCTION

Prosthetic valve infective endocarditis is a feared and potentially catastrophic complication of valvular intervention. Transcatheter aortic valve implantation has transformed the modern management of aortic stenosis and vastly altered the demographics of those patients undergoing valve replacement.

AREAS COVERED

As a relatively nascent development, what TAVI means for the epidemiology of infective endocarditis, how to identify those patients undergoing the procedure at greatest risk, and how best to prevent and manage the condition remains the subject of fervent research activity. In this review, we appraise relevant contemporary data discussing the incidence, microbiological profiles, associated risk factors and clinical outcomes of infective endocarditis after TAVI.

EXPERT OPINION

Present outcomes are poor, with exceedingly high in-hospital and long-term mortality. Evidence to support surgical management in this patient group is lacking. Prevention is therefore paramount and a logical focus for future research attention.

Uptake of uranium into desert plants in an abandoned uranium mine and its implications for phytostabilization strategies

This research assessed a variety of native desert plant species for their ability to accumulate toxic elements in an abandoned uranium mine in the Sonoran Desert. Paired soil and plant samples were collected for six species of plants that had naturally re-colonized the mine. The mine soils had a median uranium concentration of 56.0 mg kg^-1 (range: MDL to 696) while the plant samples had concentrations of 3.7 mg kg^-1 (range: MDL to 20.0). The results showed uranium bioconcentration factors (BCFs) were between 0.051 and 0.234 with the longer-living, woody species having higher concentrations than short-lived herbaceous species. These BCF values were near the high end of values reported in the literature which implies that these desert species were either better at acquiring elements or they have fewer mechanisms to eliminate elements (e.g. litterfall). The life histories of the species were then evaluated on four criteria, namely uranium BCF, inedibility, longevity, and root depth, to assess which species would be best for phytostabilization, which is the use of plants to stabilize the soil to prevent water or wind erosion that might transport contaminants off site. The goal was to select a species that would stabilize the soil without accumulating uranium in the above ground biomass where it could enter the food web and be transported off site. Ultimately, brittlebush (Encelia farinosa A. Gray ex Torr.) was selected because of its low BCF, shallow roots and reasonable longevity.

NASA GeneLab Platform Utilized for Biological Response to Space Radiation in Animal Models

Background: Ionizing radiation from galactic cosmic rays (GCR) is one of the major risk factors that will impact the health of astronauts on extended missions outside the protective effects of the Earth's magnetic field. The NASA GeneLab project has detailed information on radiation exposure using animal models with curated dosimetry information for spaceflight experiments. Methods: We analyzed multiple GeneLab omics datasets associated with both ground-based and spaceflight radiation studies that included in vivo and in vitro approaches. A range of ions from protons to iron particles with doses from 0.1 to 1.0 Gy for ground studies, as well as samples flown in low Earth orbit (LEO) with total doses of 1.0 mGy to 30 mGy, were utilized. Results: From this analysis, we were able to identify distinct biological signatures associating specific ions with specific biological responses due to radiation exposure in space. For example, we discovered changes in mitochondrial function, ribosomal assembly, and immune pathways as a function of dose. Conclusions: We provided a summary of how the GeneLab's rich database of omics experiments with animal models can be used to generate novel hypotheses to better understand human health risks from GCR exposures.

Land-based sources of marine pollution: Pesticides, PAHs and phthalates in coastal stream water, and heavy metals in coastal stream sediments in American Samoa

The island nations and territories of the South Pacific are facing a number of pressing environmental concerns, including solid waste management and coastal pollution. Here we provide baseline information on the presence and concentration of heavy metals and selected organic contaminants (pesticides, PAHs, phthalates) in 7 coastal streams and in surface waters adjacent to the Futiga landfill in American Samoa. All sampled stream sediments contained high concentrations of lead, and some of mercury. Several coastal stream waters showed relatively high concentrations of diethyl phthalate and of organophosphate pesticides, above chronic toxicity values for fish and other aquatic organisms. Parathion, which has been banned by the US Environmental Protection Agency since 2006, was detected in several stream sites. Increased monitoring and initiatives to limit non-point source land-based pollution will greatly improve the state of freshwater and coastal resources, as well as reduce risks to human health in American Samoa.

X-linked primary ciliary dyskinesia due to mutations in the cytoplasmic axonemal dynein assembly factor PIH1D3

By moving essential body fluids and molecules, motile cilia and flagella govern respiratory mucociliary clearance, laterality determination and the transport of gametes and cerebrospinal fluid. Primary ciliary dyskinesia (PCD) is an autosomal recessive disorder frequently caused by non-assembly of dynein arm motors into cilia and flagella axonemes. Before their import into cilia and flagella, multi-subunit axonemal dynein arms are thought to be stabilized and pre-assembled in the cytoplasm through a DNAAF2–DNAAF4–HSP90 complex akin to the HSP90 co-chaperone R2TP complex. Here, we demonstrate that large genomic deletions as well as point mutations involving PIH1D3 are responsible for an X-linked form of PCD causing disruption of early axonemal dynein assembly. We propose that PIH1D3, a protein that emerges as a new player of the cytoplasmic pre-assembly pathway, is part of a complementary conserved R2TP-like HSP90 co-chaperone complex, the loss of which affects assembly of a subset of inner arm dyneins.

Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disease resulting in reduced mucus clearance and impaired lung function. Here, the authors show that mutations in PIH1D3 are responsible for an X-linked form of PCD, affecting assembly of a subset of inner arm dyneins.

Face Masks for Noninvasive Ventilation: Fit, Excess Skin Hydration, and Pressure Ulcers

BACKGROUND

Pressure ulcers (stages III and IV) are serious safety events (ie, never events). Healthcare institutions are no longer reimbursed for costs to care for affected patients. Medical devices are the leading cause of pediatric pressure ulcers. Face masks for noninvasive ventilation were associated with a high percentage of pressure ulcers at our institution.

METHODS

A prospective cohort study investigated factors contributing to pressure ulcer development in 50 subjects using face masks for noninvasive ventilation. Color imaging, 3-dimensional surface imaging, and skin hydration measurements were used to identify early skin compromise and evaluate 3 interventions to reduce trauma: (1) a silicone foam dressing, (2) a water/polyethylene oxide hydrogel dressing, and (3) a flexible cloth mask. A novel mask fit technique was used to examine the impact of fit on the potential for skin compromise.

RESULTS

Fifty subjects age 10.4 ± 9.1 y participated with color images for 22, hydration for 34, and mask fit analysis for 16. Of these, 69% had diagnoses associated with craniofacial anomalies. Stage I pressure ulcers were the most common injury. Skin hydration difference was 317 ± 29 for sites with erythema versus 75 ± 28 for sites without erythema (P < .05) and smallest for the cloth mask (P < .05). Fit distance metrics differed for the nasal, oronasal, and face shield interfaces, with threshold distances being higher for the oronasal mask than the others (P < .05). Areas of high contact were associated with skin erythema and pressure ulcers.

CONCLUSIONS

This fit method is currently being utilized to select best-fit masks from available options, to identify the potential areas of increased tissue pressure, and to prevent skin injuries and their complications. Improvement of mask fit is an important priority for improving respiratory outcomes. Strategies to maintain normal skin hydration are important for protecting tissue integrity.

Soil and glass surface photodegradation of etofenprox under simulated california rice growing conditions

Photolysis is an important degradation process to consider when evaluating a pesticide's persistence in a rice field environment. To simulate both nonflooded and flooded California rice field conditions, the photolytic degradation of etofenprox, an ether pyrethroid, was characterized on an air-dried rice soil and a flooded rice soil surface by determination of its half-life (t(1/2)), dissipation rate constant (k) and identification and quantitation of degradation products using LC/MS/MS. Photodegradation was also characterized on a glass surface alone to rule out confounding soil factors. Measured photolytic dissipation rates were used as input parameters into a multimedia environmental fate model to predict etofenprox persistence in a rice field environment. Photolytic degradation proceeded at a faster rate (0.23/day, t(1/2) = 3.0 days) on the flooded soil surface compared to the air-dried surface (0.039/day, t(1/2) = 18 days). Etofenprox degradation occurred relatively quickly on the glass surface (3.1/day, t(1/2) = 0.23 days or 5.5 h) compared to both flooded and air-dried soil layers. Oxidation of the ether moiety to the ester was the major product on all surfaces (max % yield range = 0.2 ± 0.1% to 9.3 ± 2.3%). The hydroxylation product at the 4' position of the phenoxy phenyl ring was detected on all surfaces (max % yield range = 0.2 ± 0.1% to 4.1 ± 1.0%). The air-dried soil surface did not contain detectable residues of the ester cleavage product, whereas it was quantitated on the flooded soil (max % yield = 0.6 ± 0.3%) and glass surface (max % yield = 3.6 ± 0.6%). Dissipation of the insecticide in dark controls was significantly different (p < 0.05) compared to the light-exposed surfaces indicating that degradation was by photolysis. Laboratory studies and fate model predictions suggest photolysis will be an important process in the overall degradation of etofenprox in a rice field environment.

Measurements of the stratospheric plume from the mount st. Helens eruption: radioactivity and chemical composition

Gas measurements made in the stratospheric plume from the eruption of Mount St. Helens on 18 May 1980 were not consistent with a reported large injection of radon-222 into the atmosphere. No enrichment in the volatile element polonium was found in filter samples, and the ratio of polonium-210 to lead-210 was not different from background values. Data obtained with an experimental impactor, flown shortly after the eruption, showed an increase of 10(3) in the stratospheric number concentration of submicrometer sulfate particles compared to concentrations before the eruption.

Health promotion for people with disabilities: development and evaluation of the Living Well with a Disability program

People with disabilities can benefit from health promotion opportunities to reduce the incidence and severity of secondary conditions that further limit their participation in society. This paper describes participatory action research (PAR) methods we used to develop, implement and evaluate the Living Well with a Disability program. Community-based agencies that provide information and referral services to people with disabilities (independent living centers funded under Title VII, Rehabilitation Act) recruited a convenience sample of 246 people with mobility impairments to participate in a randomly assigned, wait-list control health promotion intervention study. Paper-and-pencil outcome measures included the secondary conditions surveillance instrument, unhealthy days and health care utilization. Logistic regression on outcomes controlling for demographic variables and pre-test measures indicated reductions in all three outcome variables. People with mobility impairments who participated in the Living Well with a Disability program reported less limitation from secondary conditions, fewer unhealthy days and less health care utilization. PAR methods are particularly important to design useful interventions for this population.

A prospective, randomized comparison of the Volume Diffusive Respirator vs conventional ventilation for ventilation of burned children. 2001 ABA paper

The Volume Diffusive Respirator (VDR) is a high-frequency time cycled pressure ventilator that can ventilate, oxygenate, and promote secretion removal. The VDR provides ventilation at lower airway pressures than those required for conventional ventilation in the pressure control mode (PCV). A prospective, randomized, institutional review board-approved study was conducted comparing the VDR to PCV in burned children with respiratory failure from all causes.

METHODS

Pediatric burn patients requiring ventilation were stratified by presence of inhalation injury and ventilated by VDR or PCV to achieve predefined arterial blood gases.

RESULTS

Sixty-four patients were prospectively assigned ventilator type; 32 to VDR, 32 to PCV. Data are reported as mean + SEM. Patient age was 7.4 + 0.7 years, TBSA was 56 + 3%, and number of patients with inhalation injuries was 55 (86%). Maximum peak inspiratory pressure with the VDR was significantly less than with PCV (30.9 + 0.8 cm H2O vs 39.5 + 1.8 cm H2O,P < 0.05) and the best PaO2 /FIO2 ratio was significantly higher with the VDR compared with PCV (563 + 15 vs 507 + 13, P < 0.05). No patient in the VDR group had evidence of barotrauma compared with two in the PCV group. Five patients in the PCV group died compared with two in the VDR group.

CONCLUSION

Patients ventilated with the VDR required significantly lower peak inspiratory pressure and achieved a significantly higher PaO2 /FIO2 ratio compared with PCV. This demonstrates the VDR is a safe and effective method of ventilation for pediatric burn patients and it offers advantages when compared with conventional ventilation.

Usage of triptans among migraine patients: an audit in nine GP practices

A retrospective audit was carried out to investigate triptan usage over a period of one year among 360 adult patients with migraine in nine GP practices in the UK and the Republic of Ireland. Data from patient records were analysed, in conjunction with replies to a questionnaire about patients' perceptions of their migraine and its treatment. The majority of patients included in the audit were women (83%), and most patients (81%) were aged between 35 and 64 years. Most patients in the audit population (60%) were in the lowest band of triptan usage (1-36 tablets prescribed over 12 months); 7% had moderate usage (37-53 tablets). A minority of patients appeared to be taking triptans in higher quantities: about 15% of patients had been prescribed 54-94 triptan tablets over a year, 9% had received prescriptions for 95-149 tablets and 7% had received prescriptions for 150 or more tablets. These results indicated that some migraine patients were using triptans at higher than expected rates, and suggested that some patients might have been using their prescribed triptans inappropriately to treat a headache that they incorrectly perceived as migraine (e.g. chronic daily headache). Analyses were carried out to identify predictors of high usage. Predictors identified included the use of several other (non-triptan) medications to treat conditions other than migraine, one triptan dose being reported as sufficient to treat an attack, patient's perception of all headaches as migraine and lack of concern about taking too much medication. Patients identified as using triptans at a higher than expected rate can be called in for review of migraine diagnosis, identification of possible causes of any increased frequency of attacks, and investigation of suspected non-migrainous headaches, such as chronic daily headache and medication-induced headaches. For GPs, such actions would help achieve and maintain a high standard of care for their migraine patients, thus helping to contribute towards meeting the demands of the clinical governance agenda. Audit of triptan usage may also offer financial benefits for the practice, since helping patients to avoid the inappropriate use of triptans could lead to reductions in the overall costs of triptan prescribing within the practice. The high usage predictors could be developed into a checklist of potential indicators for GPs to identify patients who may become high users if prescribed triptans and who might require closer monitoring. We recommend that patients identified as having a potential for high usage should be routinely reviewed, every 3-6 months, to ensure that they are using triptans appropriately to treat migraine. Although triptans are generally safe and well tolerated, unnecessary use of any medication should be avoided.

Induction of molecular remission by donor peripheral blood leukocyte therapy in patients relapsing with extramedullary blastic phase chronic myeloid leukemia after allogeneic bone marrow transplantation

Two patients with chronic myeloid leukemia (CML) who relapsed in blastic transformation after allogeneic bone marrow transplantation (BMT) were treated with infusions of leukapheresed peripheral blood mononuclear cells from their original donor. At relapse, their disease was characterized by symptomatic extramedullary deposits of leukemia with minimal (PCR positive, cytologically negative) involvement of bone marrow. Treatment with donor cell infusions was associated with clinical remission, return of full donor chimerism and loss of the BCR-ABL transcript detectable in bone marrow before donor leukocyte infusion (molecular remission). Donor leukocyte infusions should be considered for therapy of relapsed blastic phase CML after allogeneic BMT, especially when the relapse is primarily extramedullary and responsive to local and systemic cytoreductive therapy. However, severe GVHD and CNS relapse remain obstacles to achieving a successful long-term outcome.

Cytotoxicity of a replication-defective mutant of herpes simplex virus type 1

Replication-defective mutants of herpes simplex virus type 1 (HSV-1) may prove useful as vectors for gene transfer, particularly to nondividing cells. Cgal delta 3 is an immediate-early gene 3 (IE 3) deletion mutant of HSV-1 that expresses the lacZ gene of Escherichia coli from the human cytomegalovirus immediate-early control region but does not express viral early or late genes. This vector was able to efficiently infect and express lacZ in cells refractory to traditional methods of gene transfer. However, 1 to 3 days postinfection, Cgal delta 3 induced cytopathic effects (CPE) in many cell types, including neurons. In human primary fibroblasts Cgal delta 3 induced chromosomal aberrations and host cell DNA fragmentation. Other HSV-1 strains that caused CPE, tested under conditions of viral replication-inhibition, included mutants of the early gene UL42, the virion host shutoff function, single mutants of IE 1, IE 2, and IE 3, and double mutants of IE 3 and 4 and IE 3 and 5. Inhibition of viral gene expression by UV irradiation of virus stocks or by preexposure of cells to interferon markedly reduced the CPE. We conclude from these studies that HSV-1 IE gene expression is sufficient for the induction of CPE, although none of the five IE gene products appear to be solely responsible. After infection of human fibroblasts with Cgal delta 3 at a low multiplicity of infection, we were able to recover up to 6% of the input virus 2 weeks later by a superinfection-rescue procedure, even though the virally transduced human cytomegalovirus-lacZ transgene was not expressed at this time. It is therefore likely that inhibition or inactivation of viral IE gene expression, either for establishing latency or for the long-term transduction of foreign genes by HSV-1 vectors, is essential to avoid the death of infected cells.

Laser microsurgery in cell and developmental biology

New applications of laser microbeam irradiation to cell and developmental biology include a new instrument with a tunable wavelength (217- to 800-nanometer) laser microbeam and a wide range of energies and exposure durations (down to 25 X 10(-12) second). Laser microbeams can be used for microirradiation of selected nucleolar genetic regions and for laser microdissection of mitotic and cytoplasmic organelles. They are also used to disrupt the developing neurosensory appendages of the cricket and the imaginal discs of Drosophila.