Safety and efficacy of direct percutaneous endoscopic jejunostomy tube placement compared with surgical jejunostomy: a tertiary care analysis

BACKGROUND AND AIMS

Jejunostomy tube placements provides enteral access for feeding in eligible patients who cannot meet their nutritional needs by mouth. They can be surgically placed laparoscopically (lap-J) or with the use of a conventional open laparotomy approach (open-J). Recently, direct percutaneous endoscopic jejunostomy (DPEJ) has emerged as an alternative owing to its low cost and shorter recovery times. We sought to retrospectively compare the procedural success rates and adverse events of these methods.

METHODS

Patients were identified by querying our health system patient database and the departmental database of patients who underwent DPEJ. The patients were divided into 3 cohorts based on the procedure: DPEJ, lap-J, or open-J. Patient age and body mass index, procedural success rate, and adverse event rate were compared among the 3 groups.

RESULTS

A total of 201 patients met inclusion criteria (65 DPEJ, 111 lap-J, and 25 open-J). Procedural success rates were similar among the 3 groups (DPEJ 96.9%, lap-J 99.1%, open-J 100%; P = .702). Rates of infection and bleeding were also similar among the 3 groups. There were no cases of GI perforation. Tube dysfunction for any reason that required complete removal or replacement within 90 days occurred more often in the surgical groups than in the DPEJ group (DPEJ 0%, lap-J 35.1%, open-J 40.0%; P < .001). This was driven largely by increased rates of tube clogging and tube dislodgement in the surgical groups.

CONCLUSIONS

DPEJ is a safe and effective alternative to surgical jejunostomy in eligible patients and may be associated with decreased adverse event rates at 90 days.

Direct percutaneous endoscopic jejunostomy tube placement in patients post Roux-en-Y gastric bypass, a single tertiary care center experience

Background and study aims Obesity prevalence continues to rise in the United States with Roux-en-Y gastric bypass (RYGB) surgery being one of the most common bariatric procedures. With this trend, more patients with altered upper gastrointestinal (UGI) anatomy have required endoscopic intervention including direct percutaneous endoscopic jejunostomy (DPEJ) placement. We aimed to assess the safety and success rates of DPEJ in RYGB patients. Patients and methods All patients at a tertiary care referral center who underwent DPEJ during an 8-year period were queried from a prospectively maintained registry of all enteroscopy procedures. Duplicate cases and altered upper UGI anatomy subtypes other than RYGB were excluded. The final cohort consisted of two groups: RYGB vs native anatomy (NA). Demographic, procedural, readmission, follow-up, and complication data were recorded. Comparative analysis was performed. Results Seventy-two patients were included where 28 had RYGB and 44 had NA. Both groups had similar baseline and pre-procedure data. Procedure success rate was 89 % in RYGB patients and 98 % in NA patients ( P  = 0.13). There were no intraprocedural complications. Early and late postprocedural complication rates were similar between the groups (both 4 % vs 7 %). Average follow-up times in the RYGB and NA groups were 12.97 ± 9.35 and 13.44 ± 9.21 months, respectively. Although readmission rates at 1 and 6 months were higher in the NA versus the RYGB group (21 % vs 7 % and 25 % vs 15 %), these differences were not significant. Conclusions DPEJ can be successful and safely placed in RYGB patients with no significant difference in procedure success, complication, or readmission rates when compared to control.

Comparing the efficacy of adipose-derived and bone marrow-derived cells in a rat model of posterolateral lumbar fusion

Although bone marrow-derived mesenchymal stem cells (BMCs) have been widely used in spinal fusion procedures, adipose-derived stem cells (ASCs) offer a number of advantages as an alternative clinical cell source. This study directly compares the efficacy of ASCs and BMCs from the same donor animals to achieve successful fusion when combined with a clinical-grade bone graft substitute in a rat lumbar fusion model. ASCs and BMCs were isolated from the same Lewis donor rats and grown to passage 2 (P2). Single-level bilateral posterolateral intertransverse process lumbar fusion surgery was performed on syngeneic rats divided into three experimental groups: clinical-grade bone graft substitute alone (CBGS); CBGS+ rat ASCs (rASC); and, CBGS+ rat BMCs (rBMC). Eight weeks postoperatively, fusion was evaluated via micro-CT, manual palpation and histology. In vitro analysis of the osteogenic capacity of rBMCs and rASCs was also performed. Results indicated that the average fusion volume in the rASC group was the largest and was significantly larger than the CBGS group. Although the rASC group displayed the highest fusion rates via micro-CT and manual palpation, this difference was not statistically significant. Cell-seeded grafts showed more histological bone formation than cell-free grafts. P2 rASCs and rBMCs displayed similar in vitro osteogenic differentiation capacities. Overall, this study showed that, when combined with a clinical-grade bone graft substitute in a rat model, rASCs cells yielded the largest fusion masses and comparable fusion results to rBMCs. These results add to growing evidence that ASCs provide an attractive alternative to BMCs for spinal fusion procedures.

Comparing the efficacy of syngeneic iliac and femoral allografts with iliac crest autograft in a rat model of lumbar spinal fusion

BACKGROUND

Despite widespread use of femoral-sourced allografts in clinical spinal fusion procedures and the increasing interest in using femoral reamer-irrigator-aspirator (RIA) autograft in clinical bone grafting, few studies have examined the efficacy of femoral grafts compared to iliac crest grafts in spinal fusion. The objective of this study was to directly compare the use of autologous iliac crest with syngeneic femoral and iliac allograft bone in the rat model of lumbar spinal fusion.

METHODS

Single-level bilateral posterolateral intertransverse process lumbar spinal fusion surgery was performed on Lewis rats divided into three experimental groups: iliac crest autograft, syngeneic iliac crest allograft, and syngeneic femoral allograft bone. Eight weeks postoperatively, fusion was evaluated via microCT analysis, manual palpation, and histology. In vitro analysis of the colony-forming and osteogenic capacity of bone marrow cells derived from rat femurs and hips was also performed to determine whether there was a correlation with the fusion efficacy of these graft sources.

RESULTS

Although no differences were observed between groups in CT fusion mass volumes, iliac allografts displayed an increased number of radiographically fused fusion masses and a higher rate of bilateral fusion via manual palpation. Histologically, hip-derived grafts showed better integration with host bone than femur derived ones, likely associated with the higher concentration of osteogenic progenitor cells observed in hip-derived bone marrow.

CONCLUSIONS

This study demonstrates the feasibility of using syngeneic allograft bone in place of autograft bone within inbred rat fusion models and highlights the need for further study of femoral-derived grafts in fusion.

Effects of Intraoperative Intrawound Antibiotic Administration on Spinal Fusion: A Comparison of Vancomycin and Tobramycin in a Rat Model

BACKGROUND

Local, intrawound use of antibiotic powder, such as vancomycin and tobramycin, in spinal fusion surgery has become an increasingly common prophylactic measure in an attempt to reduce rates of postsurgical infection. However, the effects of localized antibiotic delivery on fusion remain unclear. The objective of this study was to examine the in vivo effects of intraoperative local delivery of 2 antibiotics commonly used in bone-grafting surgery on spinal fusion outcomes in a rat model.

METHODS

Single-level (L4-L5), bilateral posterolateral intertransverse process lumbar fusion surgery was performed on 60 female Lewis rats (6 to 8 weeks of age) using syngeneic iliac crest allograft mixed with clinical bone-graft substitute and varying concentrations of antibiotics (n = 12 each): (1) control without any antibiotics, (2) low-dose vancomycin (14.3 mg/kg), (3) high-dose vancomycin (71.5 mg/kg), (4) low-dose tobramycin (28.6 mg/kg), and (5) high-dose tobramycin (143 mg/kg). Eight weeks postoperatively, fusion was evaluated via micro-computed tomography (µCT), manual palpation, and histological analysis, with blinding to treatment group. In the µCT analysis, fusion-mass volumes were measured for each rat. Each spine specimen (L4-L5) was rated (manual palpation score) on a scale of 2 to 0 (2 = fused, 1 = partially fused, and 0 = non-fused).

RESULTS

The mean fusion-mass volume on µCT (mm) was as follows: control, 29.3 ± 6.2; low-dose vancomycin, 26.3 ± 8.9; high-dose vancomycin, 18.8 ± 7.9; low-dose tobramycin, 32.7 ± 9.0; and high-dose tobramycin, 43.8 ± 11.9 (control versus high-dose vancomycin, p < 0.05; and control versus high-dose tobramycin, p < 0.05). The mean manual palpation score for each group was as follows: control, 1.46 ± 0.58; low-dose vancomycin, 0.86 ± 0.87; high-dose vancomycin, 0.68 ± 0.62; low-dose tobramycin, 1.25 ± 0.71; and high-dose tobramycin, 1.32 ± 0.72 (control versus high-dose vancomycin, p < 0.05). The histological analyses demonstrated a similar trend with regard to spinal fusion volume.

CONCLUSIONS

Intraoperative local application of vancomycin, particularly at a supraphysiological dosage, may have detrimental effects on fusion-mass formation. No inhibitory effect of tobramycin on fusion-mass formation was observed.

CLINICAL RELEVANCE

When spine surgeons decide to use intraoperative intrawound antibiotics in spinal fusion surgery, they should weigh the reduction in surgical site infection against a possible inhibitory effect on fusion.

Longevity of anterior resin-bonded bridges: survival rates of two tooth preparation designs

BACKGROUND

Significant developments have occurred in the design of resin-bonded bridges (RBB) over the past two decades. They are commonly used as an alternative treatment option for a single missing tooth. The longevity of these bridges needs to be further investigated to evaluate long-term outcomes for this option to remain relevant.

METHODS

A cohort of patients who received anterior resin-bonded bridges (ARBB) over two decades was studied retrospectively. Longevity of 206 ARBB was assessed using Kaplan-Meier probability estimates. The two modified tooth preparation designs investigated were: (A) mesial and distal vertical grooves only; and (B) one proximal groove adjacent to the pontic and two palatal grooves. Age and gender of the patient cohort were also recorded.

RESULTS

Overall survival rate of ARBB was 98% at 5 years, 97.2% at 10 years, and 95.1% from 12 years till 21 years. Survival curves showed minor differences when compared for the two designs, age groups and gender of ARBB recipients. Differences in the proportion of surviving bridges for design A (95.96%) and design B (98.13%) were not statistically significant (Fisher's exact test).

CONCLUSIONS

Anterior RBB with described tooth preparation designs demonstrate a high survival rate.

Effectiveness of percutaneous flexor tenotomies for the management and prevention of recurrence of diabetic toe ulcers: a systematic review

BACKGROUND

Diabetic toe ulcers are a potentially devastating complication of diabetes. In recent years, the percutaneous flexor tenotomy procedure for the correction of flexible claw and hammer-toe contraction deformities has been proposed as a safe and effective technique for facilitating the healing of toe-deformity related diabetic ulcers. The aim of this review is to critically appraise the evidence for the effectiveness of this surgical procedure in achieving ulcer healing, prevention of re-ulceration, and to summarise the rate of post-operative complications.

METHOD

A search of medical databases, was performed to locate relevant literature. Titles were screened prior to abstract and full text review to identify articles relevant to the research question. Search terms included truncations of "tenotomy", "toe", "hallux", "digit", "diabetes" and "ulcer". Peer reviewed primary research study designs specified as suitable for systematic reviews by the Centre for Reviews and Dissemination were included. Studies were excluded if they used a concurrent secondary procedure or included non-diabetic patients without reporting outcomes separately. Included studies were appraised for quality using the Methodological Index for Non-Randomised Studies tool. Levels of evidence were subsequently assigned to each outcome of interest (healing rate and prevention of re-ulceration).

RESULTS

From a total search yield of 42 articles, 5 eligible studies (all case series designs) were identified for inclusion. Included studies were of low-to-moderate methodological quality when assessed using the MINORS tool. A total of 250 flexor tenotomy procedures were performed in a total of 163 patients. Included studies generally reported good healing rates (92-100 % within 2 months) post-op follow-up), relatively few recurrences (0-18 % at 22 months median post-op follow-up), and low incidences of infection or new deformity. Transfer ulcers developing on adjacent areas as a result of shifted pressure were reported by several authors. The validity of these results is undermined by methodological limitations inherent to case series designs such as a lack of control groups, non-randomised designs, as well as inconsistent reporting of post-intervention follow-up periods. There was level 4 evidence for the flexor tenotomy procedure in facilitating ulcer healing and preventing re-ulceration.

CONCLUSION

More definitive research evidence is needed in this area to determine whether or not the flexor tenotomy is a safe and effective treatment option for people with, or at risk of developing diabetic toe ulcers. Whilst the available literature reports that the procedure may be associated with high healing rates, relatively low recurrence rates and low incidences of post-op complications, methodological limitations restrict the value of these findings.

Mutations in ash1 and trx enhance P-element-dependent silencing in Drosophila melanogaster

In Drosophila melanogaster, the mini-w(+) transgene in Pci is normally expressed throughout the adult eye; however, when other P or KP elements are present, a variegated-eye phenotype results, indicating random w(+) silencing during development called P-element-dependent silencing (PDS). Mutant Su(var)205 and Su(var)3-7 alleles act as haplo-suppressors/triplo-enhancers of this variegated phenotype, indicating that these heterochromatic modifiers act dose dependently in PDS. Previously, we recovered a spontaneous mutation of P{lacW}ci(Dplac) called P{lacW}ci(DplacE1) (E1) that variegated in the absence of P elements, presumably due to the insertion of an adjacent gypsy element. From a screen for genetic modifiers of E1 variegation, we describe here the isolation of five mutations in ash1 and three in trx that enhance the E1 variegated phenotype in a dose-dependent and cumulative manner. These mutant alleles enhance PDS at E1, and in E1/P{lacW}ci(Dplac), but suppress position effect variegation (PEV) at In(1)w(m)(4). This opposite action is consistent with a model where ASH1 and TRX mark transcriptionally active chromatin domains. If ASH1 or TRX function is lost or reduced, heterochromatin can spread into these domains creating a sink that diverts heterochromatic proteins from other variegating locations, which then may express a suppressed phenotype.

An online spatial database of Australian Indigenous Biocultural Knowledge for contemporary natural and cultural resource management

With growing international calls for the enhanced involvement of Indigenous peoples and their biocultural knowledge in managing conservation and the sustainable use of physical environment, it is timely to review the available literature and develop cross-cultural approaches to the management of biocultural resources. Online spatial databases are becoming common tools for educating land managers about Indigenous Biocultural Knowledge (IBK), specifically to raise a broad awareness of issues, identify knowledge gaps and opportunities, and to promote collaboration. Here we describe a novel approach to the application of internet and spatial analysis tools that provide an overview of publically available documented Australian IBK (AIBK) and outline the processes used to develop the online resource. By funding an AIBK working group, the Australian Centre for Ecological Analysis and Synthesis (ACEAS) provided a unique opportunity to bring together cross-cultural, cross-disciplinary and trans-organizational contributors who developed these resources. Without such an intentionally collaborative process, this unique tool would not have been developed. The tool developed through this process is derived from a spatial and temporal literature review, case studies and a compilation of methods, as well as other relevant AIBK papers. The online resource illustrates the depth and breadth of documented IBK and identifies opportunities for further work, partnerships and investment for the benefit of not only Indigenous Australians, but all Australians. The database currently includes links to over 1500 publically available IBK documents, of which 568 are geo-referenced and were mapped. It is anticipated that as awareness of the online resource grows, more documents will be provided through the website to build the database. It is envisaged that this will become a well-used tool, integral to future natural and cultural resource management and maintenance.

Transdisciplinary synthesis for ecosystem science, policy and management: The Australian experience

Mitigating the environmental effects of global population growth, climatic change and increasing socio-ecological complexity is a daunting challenge. To tackle this requires synthesis: the integration of disparate information to generate novel insights from heterogeneous, complex situations where there are diverse perspectives. Since 1995, a structured approach to inter-, multi- and trans-disciplinary(1) collaboration around big science questions has been supported through synthesis centres around the world. These centres are finding an expanding role due to ever-accumulating data and the need for more and better opportunities to develop transdisciplinary and holistic approaches to solve real-world problems. The Australian Centre for Ecological Analysis and Synthesis (ACEAS <http://www.aceas.org.au>) has been the pioneering ecosystem science synthesis centre in the Southern Hemisphere. Such centres provide analysis and synthesis opportunities for time-pressed scientists, policy-makers and managers. They provide the scientific and organisational environs for virtual and face-to-face engagement, impetus for integration, data and methodological support, and innovative ways to deliver synthesis products. We detail the contribution, role and value of synthesis using ACEAS to exemplify the capacity for synthesis centres to facilitate trans-organisational, transdisciplinary synthesis. We compare ACEAS to other international synthesis centres, and describe how it facilitated project teams and its objective of linking natural resource science to policy to management. Scientists and managers were brought together to actively collaborate in multi-institutional, cross-sectoral and transdisciplinary research on contemporary ecological problems. The teams analysed, integrated and synthesised existing data to co-develop solution-oriented publications and management recommendations that might otherwise not have been produced. We identify key outcomes of some ACEAS working groups which used synthesis to tackle important ecosystem challenges. We also examine the barriers and enablers to synthesis, so that risks can be minimised and successful outcomes maximised. We argue that synthesis centres have a crucial role in developing, communicating and using synthetic transdisciplinary research.

Treatment time, ease of use and cost associated with use of Equashield™, PhaSeal® , or no closed system transfer device for administration of cancer chemotherapy to a dog model

This prospective experimental simulation study evaluated the efficiency, ease of use (EOU) and cost of administering chemotherapy with two closed system transfer devices (CSTD, Equashield™ and PhaSeal^® ) and no CSTD. Forty-six veterinary technicians (VT) working in oncology specialty practices were timed during chemotherapy administration simulated with water and a model canine limb 10 times with each system and with no CSTD. EOU and likelihood of recommending each system were rated by VT using visual analog scales. Costs were obtained from veterinary distributors. Administration was fastest with Equashield™ (P = 0.0003), but the difference was not enough to affect case flow. Equashield™ was easier to use than PhaSeal^® or no CSTD (P = 0.002), however VT recommended both CSTD more strongly than no CSTD (P < 0.0001). Equashield™ cost less than PhaSeal^® but was sold only in bulk quantities. CSTD did not decrease efficiency in administering chemotherapy and were readily accepted by VT.

Mutations in CG8878, a novel putative protein kinase, enhance P element dependent silencing (PDS) and position effect variegation (PEV) in Drosophila melanogaster

Genes in multicellular organisms are expressed as part of a developmental program that is largely dependent on self-perpetuating higher-order chromatin states. The mechanism of establishing and maintaining these epigenetic events is well studied in Drosophila. The first known example of an epigenetic effect was that of (PEV) in Drosophila, which has been shown to be due to gene silencing via heterochromatin formation. We are investigating a process similar to Position Effect Variegation (PEV) using a mini-w transgene, called Pci, inserted in the upstream regulatory region of ci. The mini-white+ transgene in Pci is expressed throughout the adult eye; however, when other P or KP elements are present, a variegated eye phenotype results indicating random w+ silencing during development. This P element dependent silencing (PDS) can be modified by the haplo-suppressors/triplo-enhancers, Su(var)205 and Su(var)3-7, indicating that these heterochromatic modifiers also act dose dependently in PDS. Here we use a spontaneous derivative mutation of Pci called PciE1 (E1) that variegates like PDS in the absence of P elements, presumably due to an adjacent gypsy element insertion, to screen for second-site modifier mutations that enhance variable silencing of white+ in E1. We isolated 7 mutations in CG8878, an essential gene, that enhance the E1 variegated phenotype. CG8878, a previously uncharacterized gene, potentially encodes a serine/threonine kinase whose closest Drosophila paralogue, ballchen (nhk-1), phosphorylates histones. These mutant alleles enhance both PDS at E1 and Position Effect Variegation (PEV) at w(m4), indicating a previously unknown common silencing mechanism between the two.

Nurses' understandings of suitable footwear for older people

PURPOSE

The purpose of this paper is to gain insight into nurses' understandings of what constitutes suitable footwear for older people in care homes.

DESIGN/METHODOLOGY/APPROACH

An exploratory descriptive qualitative survey was carried out of 20 registered nurses employed in six Scottish care homes for older people. Data were collected using a semi-structured questionnaire that included five open-ended questions. Content analysis was used to theme footwear perceptions.

FINDINGS

Participants had several views about what encompasses safe footwear; some were erroneous. The link between inappropriate footwear and falls was recognised by 80 per cent of respondents, but some were unclear about the features that effect or inhibit safety. No UK or international standardised guidelines were identified that advise nurses about appropriate footwear for older people.

PRACTICAL IMPLICATIONS

It is unknown whether respondents represent the nurse population because findings are restricted by a small sample size. Nonetheless, the group showed variable understanding of what constitutes safe footwear for older people and links with fall prevention. Improved nurse-education about what comprises safe footwear and the links with falls prevention in older people is required. Structured guidelines to direct nurse educators about what to teach student nurses about appropriate footwear for older people may work towards reducing falls.

ORIGINALITY/VALUE

No guidelines to direct nurses about appropriate footwear for older people in care homes have been written. Key points have been developed.

What liver transplant outcomes can be expected in the uninsured who become insured via the Affordable Care Act?

Our study objective is to measure the survival impact of insurance status following liver transplantation in a cohort of uninsured "charity care" patients. These patients are analogous to the population who will gain insurance via the Affordable Care Act. We hypothesize there will be reduced survival in charity care compared to other insurance strata. We conducted a retrospective study of 898 liver transplants from 2000 to 2010. Insurance cohorts were classified as private (n = 640), public (n = 233) and charity care (n = 23). The 1, 3 and 5-year survival was 92%, 88% and 83% in private insurance, 89%, 80% and 73% in public insurance and 83%, 72% and 51% in charity care. Compared to private insurance, multivariable regression analyses demonstrated charity care (HR 3.11, CI 1.41-6.86) and public insurance (HR 1.58, CI 1.06-2.34) had a higher 5-year mortality hazard ratio. In contrast, other measures of socioeconomic status were not significantly associated with increased mortality. The charity care cohort demonstrated the highest incidence of acute rejection and missed clinic appointments. These data suggest factors other than demographic and socioeconomic may be associated with increased mortality. Further investigations are necessary to determine causative predictors of increased mortality in liver transplant patients without private insurance.

Point mutations in a Drosophila P element abolish both P element-dependent silencing (PDS) of a transgene and repressor functions

The P elements of Drosophila melanogaster are well-studied transposons with both mobilizing and repressor functions. P elements can also variably silence the expression of certain other transgenes through a phenomenon known as P element-dependent silencing (PDS). To examine the role of the P repressor in PDS, we have induced, isolated, and characterized 22 point mutations in an archetype P element called P[SalI]89D. All mutations showed a loss in the ability to silence one or more assays for the PDS phenotype. These mutants also lost the ability to induce the suppression of variegation in P[hsp26-pt-T]39C-12, another P element-dependent phenotype. A subgroup of 11 mutations was further assayed for their ability to act as a P repressor and silence the P element promoter transcribing a lacZ ( + ) gene, and this function was lost as well. Taken together, this study supports a model of PDS acting through protein interactions, not RNA, with heterochromatic proteins to modify the extent of variegation seen in PDS. Furthermore, the common loss of functions for PDS and P repressor silencing (from another P promoter) argues for a common role of the repressor. This makes the PDS model a good system for examining P repressor functions and how they relate to transposon-mediated gene silencing in general.

The P-element-induced silencing effect of KP transposons is dose dependent in Drosophila melanogaster

Transposable elements are found in the genomes of all eukaryotes and play a critical role in altering gene expression and genome organization. In Drosophila melanogaster, transposable P elements are responsible for the phenomenon of hybrid dysgenesis. KP elements, a deletion-derivative of the complete P element, can suppress this mutagenic effect. KP elements can also silence the expression of certain other P-element-mediated transgenes in a process called P-element-dependent silencing (PDS), which is thought to involve the recruitment of heterochromatin proteins. To explore the mechanism of this silencing, we have mobilized KP elements to create a series of strains that contain single, well-defined KP insertions that show PDS. To understand the quantitative role of KP elements in PDS, these single inserts were combined in a series of crosses to obtain genotypes with zero, one, or two KP elements, from which we could examine the effect of KP gene dose. The extent of PDS in these genotypes was shown to be dose dependent in a logarithmic rather than linear fashion. A logarithmic dose dependency is consistent with the KP products interacting with heterochromatic proteins in a concentration-dependent manner such that two molecules are needed to induce gene silencing.

Contamination skin doses and attenuation of radiation by clothing

The potential operating environment following an attack using CBRN (chemical, biological, radiological, nuclear) materials has led to design work aiming to reduce the physiological burden of protective clothing, while maintaining satisfactory levels of chemical protection. In this paper, we review the radiological protection provided by these lighter, thinner clothing options. Monte Carlo modelling has been used to determine the contribution to skin dose from both beta and gamma radiation from four sources, each with different emission characteristics. The protection factors for eight materials have been characterised in terms of the surface density of each material (ranging from 50 to 482 g m⁻²). As protective clothing is made lighter and more breathable, the radiological protection is significantly reduced. This work has provided quantitative analysis of the magnitude of this reduction. A simple algorithm has been derived which can be used to estimate the protection factor for any clothing, on the basis of the surface density of the material (within the range of materials studied). These results show the need for skin radiation exposure to be considered by protective suit designers and CBRN response planners.

Can machine perfusion decrease the likelihood of discard among biopsied kidneys?

Many factors, such as donor risk factors and renal function, have been shown to be associated with an increased likelihood of discard after recovering kidneys from deceased donors. When these factors are insufficient for assessment, renal biopsy is often performed at the time of harvest to assess suitability. Our aims were to identify factors that predict the discard of a biopsied kidney and to assess the impact of machine perfusion (MP) on kidney discard. We biopsied 678 kidneys from deceased donors aged >or=40 years from 2001 to 2006. We used a logistic regression model to estimate the adjusted odds ratios for kidney discard. Thirty-nine percent (n = 261) of biopsied kidneys were discarded. Kidneys with glomerulosclerosis (GS) > 20% had the highest likelihood of discard. Other significant predictors of discard included extreme donor age, final resistance (>40), atherosclerosis, interstitial fibrosis, arteriolosclerosis, and terminal serum creatinine value (SCr) > 1.5 mg/dL. MP kidneys (n = 69) were less likely to be discarded than cold storage (CS) kidneys after adjusting for other factors (adjusted odds ratio = .13, P < .001). In conclusion, abnormal biopsy findings were associated with the highest likelihood of discard. MP was used in only 10% of the cases; however, the use of MP was associated with a decreased likelihood of discard among biopsied kidneys.

Drosophila Activin- and the Activin-like product Dawdle function redundantly to regulate proliferation in the larval brain

The Drosophila Activin-like ligands Activin-beta and Dawdle control several aspects of neuronal morphogenesis, including mushroom body remodeling, dorsal neuron morphogenesis and motoneuron axon guidance. Here we show that the same two ligands act redundantly through the Activin receptor Babo and its transcriptional mediator Smad2 (Smox), to regulate neuroblast numbers and proliferation rates in the developing larval brain. Blocking this pathway results in the development of larvae with small brains and aberrant photoreceptor axon targeting, and restoring babo function in neuroblasts rescued these mutant phenotypes. These results suggest that the Activin signaling pathway is required for producing the proper number of neurons to enable normal connection of incoming photoreceptor axons to their targets. Furthermore, as the Activin pathway plays a key role in regulating propagation of mouse and human embryonic stem cells, our observation that it also regulates neuroblast numbers and proliferation in Drosophila suggests that involvement of Activins in controlling stem cell propagation may be a common regulatory feature of this family of TGF-beta-type ligands.

Mutation analysis of Drosophila dikar/CG32394, homologue of the chromatin-remodelling gene CECR2

The mammalian CECR2 protein contains a highly conserved bromodomain and forms a chromatin-remodelling complex with the ISWI homologue SNF2L. Mutation of the mouse CECR2 homologue results in a neural tube defect. Here we describe the characterization of the Drosophila melanogaster homologue of CECR2. Originally annotated as 2 genes, dikar and CG32394 now appear to encode both a long dikar/CG32394 transcript homologous to CECR2 and a truncated transcript missing the bromodomain. This truncated transcript may be specific to Diptera, as it is predicted from the genomic sequences of several other dipteran species but it is not predicted in the honey bee, Apis mellifera, and it is not found in mammals. Five different P element-mediated 5' deletions of the Drosophila dikar gene were generated. All mutants were homozygous-viable and the 3 mutants examined further displayed continued, albeit aberrant, transcription of dikar/CG32394. In a previous study, a dikar insertion mutation was associated with long-term memory deficits. However, the 2 deletion mutants tested here showed normal long-term memory, suggesting that the memory deficit associated with the dikar P element insertion is not due to disruption of dikar. No genetic interaction was seen between Iswi and dikar mutations. This study therefore suggests that the lack of a visible phenotype in dikar mutants is due to compensation by a second gene, possibly acf1.

An association between autoreactive antibodies and anti-interferon-beta antibodies in multiple sclerosis

Approximately 5-25% of interferon-beta (IFN-beta) treated multiple sclerosis (MS) patients develop anti-IFN-beta neutralizing antibodies (NAb) but the patient-specific variables associated with the risk of developing anti-IFN-beta antibodies are poorly understood. Anti-IFN-beta NAb are a subset of anti-IFN-beta binding antibodies (BAb) and all patients with NAb generally have high levels of associated BAb. The purpose of this research was to assess the association between autoreactive antibodies (ARAB) and the risk of developing anti-IFN-beta BAb in MS patients. This was a retrospective study that included consecutive patients diagnosed with clinically definite MS evaluated at our center and considered appropriate for IFN-beta therapy. The patients were tested for various subtypes of antiphospholipid antibodies (APLA) including anti-phosphatidylethanolamine (APE), anti-phosphatidylserine (APS), and anti-cardiolipin (ACA) antibodies, and other ARAB, antinuclear and anti-neutrophilic cytoplasmic antibodies, anti-thyroid peroxidase antibodies (ATA), anti-SS-A and anti-SS-B antibodies. BAb levels were assessed using a commercial binding ELISA assay. A total of 33 patients (mean age: 45.4 years, 85% female) were enrolled; 15 patients were negative and 18 patients were positive for BAb. APLA or ATA were present in 95% (17 of 18 patients) of patients positive for BAb. In comparison, APLA or ATA occurred in only 27% (four of 15 patients) of patients in the BAb negative group. The associations between the occurrence of BAb and the occurrence of high APLA or ATA were significant (chi2 = 13.4, P<0.001in Fisher exact test). The odds ratio for the association was 46.8 (with a 95% confidence interval range of 4.6-475). No significant correlations were found for other ARAB. The presence of autoreactive antibodies, particularly APLA and ATA is associated with increased risk of occurrence of IFN-beta BAb in MS patients on long-term IFN-beta therapy.

Headache and temporomandibular disorders: evidence for diagnostic and behavioural overlap

To assess the diagnostic and behavioural overlap of headache patients with temporomandibular disorders (TMD), individuals recruited from the general population with self-described headaches were compared with non-headache controls. The examination and diagnostic procedures in the Research Diagnostic Criteria (RDC) for TMD were applied to both sets of subjects by a blinded examiner. Following their examination, subjects used experience sampling methods to obtain data on pain, tooth contact, masticatory muscle tension, emotional states and stress. Results showed that a significantly higher proportion of the headache patients received an RDC/TMD diagnosis of myofascial pain than non-headache controls. Headache patients also reported significantly more frequent and intense tooth contact, more masticatory muscle tension, more stress and more pain in the face/head and other parts of the body than non-headache controls. These results are similar to those reported for TMD patients and they suggest that headache patients and TMD patients overlap considerably in diagnosis and oral parafunctional behaviours.

Gene transposition as a cause of hybrid sterility in Drosophila

We describe reproductive isolation caused by a gene transposition. In certain Drosophila melanogaster-D. simulans hybrids, hybrid male sterility is caused by the lack of a single-copy gene essential for male fertility, JYAlpha. This gene is located on the fourth chromosome of D. melanogaster but on the third chromosome of D. simulans. Genomic and molecular analyses show that JYAlpha transposed to the third chromosome during the evolutionary history of the D. simulans lineage. Because of this transposition, a fraction of hybrids completely lack JYAlpha and are sterile, representing reproductive isolation without sequence evolution.

Gawky is a component of cytoplasmic mRNA processing bodies required for early Drosophila development

In mammalian cells, the GW182 protein localizes to cytoplasmic bodies implicated in the regulation of messenger RNA (mRNA) stability, translation, and the RNA interference pathway. Many of these functions have also been assigned to analogous yeast cytoplasmic mRNA processing bodies. We have characterized the single Drosophila melanogaster homologue of the human GW182 protein family, which we have named Gawky (GW). Drosophila GW localizes to punctate, cytoplasmic foci in an RNA-dependent manner. Drosophila GW bodies (GWBs) appear to function analogously to human GWBs, as human GW182 colocalizes with GW when expressed in Drosophila cells. The RNA-induced silencing complex component Argonaute2 and orthologues of LSm4 and Xrn1 (Pacman) associated with 5′–3′ mRNA degradation localize to some GWBs. Reducing GW activity by mutation or antibody injection during syncytial embryo development leads to abnormal nuclear divisions, demonstrating an early requirement for GWB-mediated cytoplasmic mRNA regulation. This suggests that gw represents a previously unknown member of a small group of genes that need to be expressed zygotically during early embryo development.

Suppression of Botrytis Blight of Begonia by Trichoderma hamatum 382 in Peat and Compost-Amended Potting Mixes

Inoculation of an industry standard light sphagnum peat potting mix with Trichoderma hamatum 382 (T382) significantly (P = 0.05) reduced the severity of Botrytis blight, caused by Botrytis cinerea, on begonia plants grown in a greenhouse. In data combined from three experiments, the degree of control provided by T382 did not differ significantly (P = 0.05) from that provided by weekly topical sprays with chlorothalonil. In addition, T382 significantly (P = 0.05) increased shoot dry weight and salability of flowering plants. Incorporation of composted cow manure (5%, vol/vol) into the light peat mix also significantly (P = 0.05) decreased blight severity while shoot dry weight and salability were increased. Blight severity on plants in this compost mix did not differ significantly (P = 0.05) from that on those in the light peat mix inoculated with T382. Finally, T382 and chlorothalonil did not significantly (P = 0.05) affect blight severity, shoot dry weight, or salability of plants grown in the compost mix. Spatial separation was maintained in begonias between the biocontrol agent T382 and the pathogen. It was concluded, therefore, that the decrease in disease severity provided by inoculation of the peat mix with T382 most likely was due to systemic resistance induced in begonia against Botrytis blight. The suppressive effect of the compost mix against Botrytis blight was unusual because composts typically do not provide such effects unless inoculated with a biocontrol agent capable of inducing systemic resistance in plants to disease.

Localized versus regional hyperthermia: comparison of xenotransplants treated with a small animal ultrasound system and waterbath limb immersion

The response of xenotransplants were compared with waterbath immersion vs focal ultrasound (US) hyperthermia using tumour growth delay, immunhistochemistry and histopathology assays. Waterbath hyperthermia was performed by limb immersion. Precautions were taken to minimize total body heating by surrounding the mouse with plastic insulators. Thermometry was performed with clinical-grade, 20-gauge needle thermocouples and monitored with a Labthermics unit. Significant differences in cytotoxicity between ultrasound and waterbath treatment of tumors at 43 degrees C were observed as determined by TUNNEL assay. Conversely, contralateral (non-treated) tumours in animals treated with similar temperature demonstrated no significant differences between modalities. Western blot analysis revealed increased hsp70 induction at 43 degrees C in waterbath vs focal ultrasound hyperthermia. Comparison of tumour growth delay between tumours heated with waterbath vs ultrasound at 43 degrees C but not at 41 degrees C revealed significant differences. This is the first study comparing localized vs regional hyperthermia using the small animal ultrasound system (SAHUS) delivery system. Consistent ultrasound hyperthermia can be achieved throughout a xenotransplant. At equivalent temperature of 43 degrees C for 60?min, waterbath hyperthermia demonstrated greater local response vs ultrasound hyperthermia.

Using pool noodles to teach mitosis and meiosis

Although mitosis and meiosis are fundamental to understanding genetics, students often find them difficult to learn. We suggest using common "pool noodles" as teaching aids to represent chromatids in classroom demonstrations. Students use these noodles to demonstrate the processes of synapsis, segregation, and recombination. Student feedback has been overwhelmingly positive.

Mutations in Su(var)205 and Su(var)3-7 suppress P-element-dependent silencing in Drosophila melanogaster

In Drosophila melanogaster, the w(+) transgene in P[lacW]ci(Dplac) is uniformly expressed throughout the adult eye. However, when other P elements are present, this w(+) transgene is randomly silenced and this produces a variegated eye phenotype. This P-element-dependent silencing (PDS) is limited to w(+) transgenes inserted in a specific region on chromosome 4. In a screen for genetic modifiers of PDS, we isolated mutations in Su(var)205, Su(var)3-7, and two unidentified genes that suppress this variegated phenotype. Therefore, only a few of the genes encoding heterochromatic modifiers act dose dependently in PDS. In addition, we recovered two spontaneous mutations of P[lacW]ci(Dplac) that variegate in the absence of P elements. These P[lacW]i(Dplac) derivatives have a gypsy element inserted proximally to the P[lacW]ci(Dplac) insert. The same mutations that suppress PDS also suppress w(+) silencing from these P[lacW]ci(Dplac) derivative alleles. This indicates that both cis-acting changes in sequence and trans-acting P elements cause a similar change in chromatin structure that silences w(+) expression in P[lacW]ci(Dplac). Together, these results confirm that PDS occurs at P[lacW]ci(Dplac) because of the chromatin structure at this chromosomal position. Studying w(+) variegation from P[lacW]ci(Dplac) provides a model for the interactions that can enhance heterochromatic silencing at single P-element inserts.

High-resolution mapping of the Drosophila fourth chromosome using site-directed terminal deficiencies

For more than 80 years, the euchromatic right arm of the Drosophila fourth chromosome (101F-102F) has been one of the least genetically accessible regions of the fly genome despite the fact that many important genes reside there. To improve the mapping of genes on the fourth chromosome, we describe a strategy to generate targeted deficiencies and we describe 13 deficiencies that subdivide the 300 kb between the cytological coordinates 102A6 and 102C1 into five discrete regions plus a 200-kb region from 102C1 to 102D6. Together these deficiencies substantially improve the mapping capabilities for mutant loci on the fourth chromosome.

Molecular mapping of deletion breakpoints on chromosome 4 of Drosophila melanogaster

As part of our effort to induce and identify mutations in all genes on chromosome 4 of Drosophila melanogaster, we have mapped the breakpoints of eight chromosome 4 deficiencies relative to the predicted genes along this chromosome. Although the approximate locations of Df(4)G, Df(4)C3, Df(4)M101-62f, Df(4)M101-63a, Df(4)J2, Df(4)O2, Df(4)C1-10AT, and Df(4)B2-2D are known (some from cytological observations and others predicted from P element locations), the extents of these deletions have not been mapped with respect to the predicted genes identified by the Drosophila Genome Project. Polymerase chain reaction primers were designed to amplify the predicted exons of all chromosome 4 genes, and homozygous embryos for each deficiency were identified and their DNA used to test for the presence or absence of these exons. By testing for the inability to amplify various exons along the length of the chromosome, we were able to determine which predicted genes are missing in each deficiency. The five deficiencies, Df(4)G, Df(4)C3, Df(4)C1-10AT, and Df(4)B2-20 (all terminal deletions), and Df(4)M101-62f (a proximal interstitial deletion), enabled us to partition the gene-containing, right arm of chromosome 4 into five regions. Region A [uncovered by Df(4)M101-62f] contains the proximal-most 21 genes; region B [uncovered by Df(4)B2-2D] contains the next 12 genes; region C [uncovered by Df(4)B2-2D and Df(4)C1-10AT] contains the next 17 genes; region D [uncovered by Df(4)B2-2D, Df(4)C1-10AT, and Df(4)C3] contains the next 21 genes; and region E [uncovered by Df(4)B2-2D, Df(4)C1-10AT, Df(4)C3, and Df(4)G] contains the distal-most ten genes. By using Df(4)M101-62f, Df(4)B2-2D, Df(4)C1-10AT, Df(4)C3, and Df(4)G in complementation tests, we can assign newly induced recessive lethal mutations to one of the five regions on chromosome 4. This will substantially reduce the amount of DHPLC analysis required to match each mutation to a predicted transcript on chromosome 4.

Characterization of the adenosine deaminase-related growth factor (ADGF) gene family in Drosophila

A novel family of growth factors, with sequence similarity to adenosine deaminase, has been identified in various organisms including flesh fly, tsetse fly, sand fly, mollusk and human. The human homologue, CECR1, is a candidate gene for the genetic disorder cat eye syndrome. Here, we describe six members of this growth factor family in Drosophila and two in vertebrates. The six Drosophila genes, named adenosine deaminase-related growth factors (ADGF), are found at three different chromosomal locations, with one singleton, two in an inverted orientation, and three in a tandem arrangement. These genes show distinct patterns of expression as measured by RT-PCR and Northern blots, indicating gene-specific function. The presence of six ADGF genes in the Drosophila genome suggests that gene duplication and divergence has been important for these growth factors in insect development. Phylogenetic analysis of the 14 extant ADGF-like gene products shows there are at least three major groups, two of which are found in Drosophila. The third appears specific to the vertebrate line. Seven gene duplications are inferred among the ADGF-like genes, most of which occurred long before the origin of Drosophila. Our analysis predicts the existence of several other unsampled ADGF-like genes, both within the species examined here, and in other related invertebrates.

Radiotherapy for epithelial skin cancer

PURPOSE

To retrospectively review patterns of failure, cosmesis, and outcomes according to treatment modality of patients with histologically confirmed epithelial skin cancer.

METHODS AND MATERIALS

The records of 468 patients having 531 lesions were analyzed; 389 basal cell carcinomas and 142 squamous cell carcinomas were treated, 167 of which were recurrent tumors. Median follow-up was 5.8 years. Electron beam irradiation was used in 19%, superficial x-rays in 60%, a combination of electron beam and superficial x-rays in 20%, and megavoltage photons in <2%.

RESULTS

The overall local tumor control rate was 89%; it was 93% for previously untreated lesions and 80% for recurrent lesions. Patients with basal cell carcinoma had a 92% overall control rate; patients with squamous cell carcinoma 80%. Multivariate analysis showed that local failure was related to the daily dose fractionation. The maximal diameter of the lesion and pathologic tumor type were also significant (p 0.01). Treatment type, patient age, and treatment duration were not significant. Overall, 92% of the treated population with cosmesis data had excellent or good results. The overall complication rate was 5.8%, consisting primarily of soft-tissue necrosis.

CONCLUSIONS

Radiotherapy remains an excellent treatment modality for epithelial skin cancer. Local tumor control, cosmesis, and complications are related to the size of the primary lesion. Recurrent lesions fared worse, and therefore treatment at the earliest possible stage is strongly recommended.