Utilization and optimization of a waste stream cellulose culture medium for pigment production by Penicillium spp

AIMS

This research sought to determine optimal corn waste stream-based fermentation medium C and N sources and incubation time to maximize pigment production by an indigenous Indonesian Penicillium spp., as well as to assess pigment pH stability.

METHODS AND RESULTS

A Penicillium spp. was isolated from Indonesian soil, identified as Penicillium resticulosum, and used to test the effects of carbon and nitrogen type and concentrations, medium pH, incubation period and furfural on biomass and pigment yield (PY) in a waste corncob hydrolysate basal medium. Maximum red PY (497.03 ± 55.13 mg l(-1)) was obtained with a 21 : 1 C : N ratio, pH 5.5-6.0; yeast extract-, NH(4) NO(3)-, NaNO(3)-, MgSO(4) ·7H(2) O-, xylose- or carboxymethylcellulose (CMC)-supplemented medium and 12 days (25 °C, 60-70% relative humidity, dark) incubation. C source, C, N and furfural concentration, medium pH and incubation period all influenced biomass and PY. Pigment was pH 2-9 stable.

CONCLUSIONS

Penicillium resticulosum demonstrated microbial pH-stable-pigment production potential using a xylose or CMC and N source, supplemented waste stream cellulose culture medium.

SIGNIFICANCE AND IMPACT OF THE STUDY

Corn derived, waste stream cellulose can be used as a culture medium for fungal pigment production. Such application provides a process for agricultural waste stream resource reuse for production of compounds in increasing demand.

Development of a social morbidity score in patients with chronic ulcerative colitis as a potential guide to treatment

AIM

Present quality of life instruments for inflammatory bowel disease do not evaluate many social aspects of patients' lives that are potentially important in clinical decision making. We have developed a new Social Impact of Chronic Conditions - Inflammatory Bowel Disease (SICC-IBD) questionnaire to assess these areas.

METHOD

A 34-item questionnaire was piloted to determine quality of life relating to education, personal relationships, employment, independence and finance. It was compared with the Short Form 36-Item version 2 (SF-36v2) and the Inflammatory Bowel Disease Questionnaire (IBDQ) in 150 patients with chronic ulcerative colitis on an endoscopic surveillance register who had never had surgery.

RESULTS

Reliability and validity testing enabled the questionnaire to be shortened to only eight items. There was a high level of reliability (Cronbach's α=0.72). The questionnaire correlated well with the social functioning domain of the SF-36 (rs=0.56) and was able to distinguish clinical severity of disease.

CONCLUSION

The SICC-IBD is a new tool for assessment of patients with ulcerative colitis, which has identified new aspects of social disability for further study and for potential use as an additional tool in therapy decisions.

Mitochondrial-nuclear communication by prohibitin shuttling under oxidative stress

Mitochondrial-nuclear communication is critical for maintaining mitochondrial activity under stress conditions. Adaptation of the mitochondrial-nuclear network to changes in the intracellular oxidation and reduction milieu is critical for the survival of retinal and retinal pigment epithelial (RPE) cells, in relation to their high oxygen demand and rapid metabolism. However, the generation and transmission of the mitochondrial signal to the nucleus remain elusive. Previously, our in vivo study revealed that prohibitin is upregulated in the retina, but downregulated in RPE cells in the aging and diabetic model. In this study, the functional role of prohibitin in the retina and RPE cells was examined using biochemical methods, including a lipid binding assay, two-dimensional gel electrophoresis, immunocytochemistry, Western blotting, and a knockdown approach. Protein depletion by siRNA characterized prohibitin as an anti-apoptotic molecule in mitochondria, while the lipid binding assay demonstrated subcellular communication between mitochondria and the nucleus under oxidative stress. The changes in the expression and localization of mitochondrial prohibitin triggered by reactive oxygen species are crucial for mitochondrial integrity. We propose that prohibitin shuttles between mitochondria and the nucleus as an anti-apoptotic molecule and a transcriptional regulator in a stress environment in the retina and RPE cells.

The National Bowel Cancer Audit: the risks and benefits of moving to open reporting of clinical outcomes

BACKGROUND

The government's proposals to openly report clinical outcomes poses challenges to the National Bowel Cancer Audit now funded by the UK department of health.

AIM

To identify the benefits and risks of open reporting and to propose ways the risks might be minimized.

METHODS

A review of the literature on clinical audit and the consequences of open reporting.

RESULTS

There are significant potential benefits of a national audit of bowel cancer including protecting patients from sub-standard care, providing clinicians with externally validated evidence of their performance, outcome data for clinical governance and evidence that increases in government expenditure are achieving improvements in survival from bowel cancer. These benefits will only be achieved if the audit captures most of the cases of bowel cancer in the UK, the data collected is complete and accurate, the results are risk adjusted and these are presented to the public in a way that is fair, clear and understandable. Involvement of clinicians who have confidence in the results of the audit and who actively compare their own results against a national standard is essential. It is suggested that a staged move to open reporting should minimise the risk of falsely identifying an outlying unit.

CONCLUSION

The fundamental aim of the National Bowel Cancer Audit is the pursuit of excellence by identification and adoption of best practice. This could achieve a continuous improvement in the care of all patients with bowel cancer in the UK. The ACPGBI suggests a safer way of transition to open reporting to avoid at least some of its pitfalls.

Short interval time measurement by a parasitoid wasp

The number of eggs laid by the parasitoid wasp Trichogramma varies with host volume. The duration of the wasp's initial transit across the host surface during host examination is used to determine the number of eggs laid. A 2.5-second reduction in initial transit resulted in a 30% reduction in eggs oviposited, demonstrating that these wasps measure short time intervals. This measure is used for progeny allocation independent of host body size.

Genome biology of the cyclostomes and insights into the evolutionary biology of vertebrate genomes

The jawless vertebrates (lamprey and hagfish) are the closest extant outgroups to all jawed vertebrates (gnathostomes) and can therefore provide critical insight into the evolution and basic biology of vertebrate genomes. As such, it is notable that the genomes of lamprey and hagfish possess a capacity for rearrangement that is beyond anything known from the gnathostomes. Like the jawed vertebrates, lamprey and hagfish undergo rearrangement of adaptive immune receptors. However, the receptors and the mechanisms for rearrangement that are utilized by jawless vertebrates clearly evolved independently of the gnathostome system. Unlike the jawed vertebrates, lamprey and hagfish also undergo extensive programmed rearrangements of the genome during embryonic development. By considering these fascinating genome biologies in the context of proposed (albeit contentious) phylogenetic relationships among lamprey, hagfish, and gnathostomes, we can begin to understand the evolutionary history of the vertebrate genome. Specifically, the deep shared ancestry and rapid divergence of lampreys, hagfish and gnathostomes is considered evidence that the two versions of programmed rearrangement present in lamprey and hagfish (embryonic and immune receptor) were present in an ancestral lineage that existed more than 400 million years ago and perhaps included the ancestor of the jawed vertebrates. Validating this premise will require better characterization of the genome sequence and mechanisms of rearrangement in lamprey and hagfish.

Bacteriocin Typing of Burkholderia (Pseudomonas) solanacearum Race 1 of the French West Indies and Correlation with Genomic Variation of the Pathogen

Burkholderia solanacearum race 1 isolates indigenous to the French West Indies were characterized by bacteriocin typing and two genomic fingerprinting methods: pulsed-field gel electrophoresis of genomic DNA digested by rare-cutting restriction endonucleases (RC-PFGE) and PCR with primers corresponding to repetitive extragenic palindromic (REP), enterobacterial repetitive intergenic consensus (ERIC), and BOX elements (collectively known as rep-PCR). The survey comprised 24 reference strains and 65 isolates obtained from a field trial in Guadeloupe in 1993. Comparison of the data identified RC-PFGE as the most discriminatory method, delineating 17 pulsed-field gel profile types. rep-PCR and bacteriocin typing identified nine rep-PCR profile types and nine bacteriocin groups. Independent determination of similarity coefficients and clustering of RC-PFGE and rep-PCR data identified six groups common to both sets of data that correlated to biovar and bacteriocin groups. Further study of bacteriocin production in planta gave results consistent with in vitro bacteriocin typing. It was observed that spontaneous bacteriocin-resistant mutants exhibited a cross-resistance to other bacteriocins as identified by the typing scheme and that such mutants possessed a selective advantage for growth over isogenic nonmutants in the presence of a bacteriocin. The results are significant in the search for biological control of disease by nonpathogenic mutants of the wild-type organism.

Long-term failure and function after restorative proctocolectomy - a multi-centre study of patients from the UK National Ileal Pouch Registry

OBJECTIVE

There is little information on the long-term failure and function after restorative proctocolectomy (RPC). The results of data submitted to a national registry were analysed.

METHOD

The UK National Pouch Registry was established in 2004. By 2006, it comprised data collected from ten centres between 1976 and 2006. The long-term failure and functional outcome were determined. Trends over time were assessed using the gamma statistic or the Kruskal-Wallis statistic wherever appropriate.

RESULTS

In all, 2491 patients underwent primary RPC over a median of 54 months (range 1 month to 28.9 years). Of these, 127 (5.1%) underwent abdominal salvage surgery. The incidence of failure (excision or indefinite diversion) was 7.7% following primary and 27.5% following salvage RPC (P < 0.001). The median frequency of defaecation/24 h was five including one at night. Nocturnal seepage occurred in 8% at 1 year, rising to 15.4% at 20 years (P = 0.037). Urgency was experienced by 5.1% of patients at 1 year rising to 9.1% at 15 years (P = 0.022). Stool frequency and the need for antidiarrhoeal medication were greater following salvage RPC.

CONCLUSION

In patients retaining anal function after RPC, frequency of defaecation was stable over 20 years. Faecal urgency and minor incontinence worsened with time. Function after salvage RPC was significantly worse.

Recurrent nuclear DNA introgression accompanies chloroplast DNA exchange between two eucalypt species

Numerous studies within plant genera have found geographically structured sharing of chloroplast (cp) DNA among sympatric species, consistent with introgressive hybridization. Current research is aimed at understanding the extent, direction and significance of nuclear (nr) DNA exchange that accompanies putative cpDNA exchange. Eucalyptus is a complex tree genus for which cpDNA sharing has been established between multiple species. Prior phylogeographic analysis has indicated cpDNA introgression into the widespread forest species Eucalyptus globulus from its rare congener E. cordata. In this study, we use AFLP markers to characterize corresponding nrDNA introgression, on both a broad and fine spatial scale. Using 388 samples we examine (i) the fine-scale spatial structure of cp and nrDNA introgression from E. cordata into E. globulus at a site in natural forest and (ii) broad-scale patterns of AFLP marker introgression at six additional mixed populations. We show that while E. globulus and E. cordata retain strongly differentiated nuclear gene pools overall, leakage of nrDNA occurs at mixed populations, with some AFLP markers being transferred to E. globulus recurrently at different sites. On the fine scale, different AFLP fragments show varying distances of introgression into E. globulus, while introgression of cpDNA is extensive. The frequency of E. cordata markers in E. globulus is correlated with spatial proximity to E. cordata, but departs from expectations based on AFLP marker frequency in E. cordata, indicating that selection may be governing the persistence of introgressed fragments in E. globulus.

Some aspects of the gross and fine structure of the amphibian papilla in the labyrinth of the newt, Triturus cristatus

Each receptor cell in the sensory macula bears a number of stereocilia and one peripherally located kinocilium; in the two halves of the macula, the kinocilia lie on opposite sides of their associated stereocilia. The morphological axes of the receptor cells are approximately parallel to the long axis of the papilla. The gelatinous cupula overlying the macula extends almost to the opposite wall of the papilla. These structural features are discussed in connection with both the proposed function of the papilla as a vibration detector and the possible evolutionary relationships with other acousticolateralis receptors.

HDAC inhibitors regulate claudin-1 expression in colon cancer cells through modulation of mRNA stability

Expression and cellular distribution of claudin-1, a tight junction protein, is dysregulated in colon cancer and its overexpression in colon cancer cells induced dedifferentiation and increased invasion. However, the molecular mechanism(s) underlying dysregulated claudin-1 expression in colon cancer remains poorly understood. Histone deacetylase (HDAC)-dependent histone acetylation is an important mechanism of the regulation of cancer-related genes and inhibition of HDACs induces epithelial differentiation and decreased invasion. Therefore, in this study, we examined the role of HDAC-dependent epigenetic regulation of claudin-1 in colon cancer. In this study, we show that sodium butyrate and Trichostatin A (TSA), two structurally different and widely used HDAC inhibitors, inhibited claudin-1 expression in multiple colon cancer cell lines. Further studies revealed modulation of claudin-1 mRNA stability by its 3'-UTR as the major mechanism underlying HDAC-dependent claudin-1 expression. In addition, overexpression of claudin-1 abrogated the TSA-induced inhibition of invasion in colon cancer cells suggesting functional crosstalk. Analysis of mRNA expression in colon cancer patients, showed a similar pattern of increase in claudin-1 and HDAC-2 mRNA expression throughout all stages of colon cancer. Inhibition of claudin-1 expression by HDAC-2-specific small interfering RNA further supported the role of HDAC-2 in this regulation. Taken together, we report a novel post-transcriptional regulation of claudin-1 expression in colon cancer cells and further show a functional correlation between claudin-1 expression and TSA-mediated regulation of invasion. As HDAC inhibitors are considered to be promising anticancer drugs, these new findings will have implications in both laboratory and clinical settings.

Amphibian sex determination: segregation and linkage analysis using members of the tiger salamander species complex (Ambystoma mexicanum and A. t. tigrinum)

Little is known about the genetic basis of sex determination in vertebrates though considerable progress has been made in recent years. In this study, segregation analysis and linkage mapping were performed to localize an amphibian sex-determining locus (ambysex) in the tiger salamander (Ambystoma) genome. Segregation of sex phenotypes (male and female) among the second generation individuals of interspecific crosses (Ambystoma mexicanum x Ambystoma tigrinum tigrinum) was consistent with Mendelian expectations, although a slight female bias was observed. Individuals from these same crosses were typed for single-nucleotide polymorphisms distributed throughout the genome to identify molecular markers for ambysex. A marker (E24C3) was identified approximately 5.9 cM from ambysex. Linkage of E24C3 to ambysex was independently validated in a second, intraspecific cross (A. mexicanum). Interestingly, ambysex locates to the tip of one of the larger linkage groups of the Ambystoma meiotic map. Considering that this location does not show reduced recombination, we speculate that the ambysex locus may have arisen quite recently, within the last few million years. Localization of ambysex sets the stage for gene identification and provides important tools for studying the effect of sex in laboratory and natural populations of this model amphibian system.

Assessment of the mucosa of the indefinitely diverted ileo-anal pouch

OBJECTIVE

One surgical option to treat failure after restorative proctocolectomy (RPC) is indefinite diversion (ID) without excision of the pouch. The study aimed to assess the mucosal morphology of the pouch and ileoanal anastomosis (IAA) over time after ID with particular reference to inflammation, dysplasia and carcinoma.

METHOD

Patients with ID were identified from the hospital's Ileal Pouch Database. Individuals were invited by mail to attend for flexible pouchoscopy and biopsy from the ileal pouch and immediately distal to the IAA.

RESULTS

Of 1822 patients on the database, 28 had undergone ID. Of these, 20 patients (18 ulcerative colitis, one familial adenomatous polyposis, one pseudo-obstruction) of median age 42 (18-67) years took part. There were eight males. The median (range) intervals from diagnosis of primary disease, pouch surgery and ID to the time of study were 221 (63-410), 146 (31-314) and 44 (10-159) months respectively. One patient had dysplasia in the original resection specimen. Five patients developed type C changes in the pouch. Of these three were identified between RPC and ID, one developed between ID and the present assessment and one was identified for the first time at the present assessment. No case of dysplasia or cancer was found in any of the biopsies. Rectal mucosa was found in biopsies from the IAA in four patients (three stapled; one handsewn); this was inflamed in three patients.

CONCLUSION

At a median follow-up of 12 years after RPC and 3.6 years after indefinite diversion no instance of dysplasia or carcinoma in the ileal reservoir or distal to the IAA was found in any of the 20 patients having ID. Type C changes occurred at some time in five (25%) patients, indicating the importance of continued follow up.

Quality of life after indefinite diversion/pouch excision in ileal pouch failure patients

OBJECTIVE

Pouch failure occurs in up to 10% of patients over a 10-year period for a variety of reasons. One surgical option is pouch excision (PE) and form a permanent ileostomy. This is a major procedure with potential serious complications. An alternative is indefinite diversion (ID) of the pouch without excision. The aim of this study was to examine the quality of life and functional outcome in these two groups of patients.

METHOD

Ninety-seven patients were identified from the database to have either PE or ID. Fifty-three patients (17 men) responded; comprising 31 patients after PE and 22 patients with ID in a case-control study and completed the SF-36 general health survey and the Cleveland Clinic Foundation (CCF) functional outcomes questionnaire.

RESULTS

There was no significant difference in the domains of SF-36 between the two groups (P > 0.18). All patients with PE had an end ileostomy whereas most patients with ID had a loop ileostomy (18 loop vs 4 end). There was no difference in stoma related complications except for stoma retraction in ID (7%vs 47%; P = 0.003). There was no significant difference in urinary symptoms between PE and ID groups (weak stream 26%vs 14%; P = 0.49, nocturia 22%vs 4%; P = 0.12, urgency 22%vs 9%; P = 0.28, urinary incontinence 22%vs 14%; P = 0.72 respectively). There was no difference in sexually active patients (73%vs 94%; P = 0.11). Of the seven male PE patients, five (71%) could achieve an erection and four (57%) could maintain an erection, compared with all 10 male patients in the ID group (P = 0.151 and 0.05 respectively). Thirty-three per cent of patients with PE and 62% of patients with ID reported that they would have pouch surgery again if indicated (P = 0.052) and 58% of patients with PE and 81% of patients with ID reported that they would recommend pouch surgery to others (P = 0.129). No case of dysplasia was seen in 18 of 22 ID patients in whom histology was available.

CONCLUSION

Quality of life after PE or ID was no different and male sexual function was significantly better after ID. Retraction of the stoma was more common in this group.

Proteomics of the peroxisome

Genomes provide us with a blue print for the potential of a cell. However, the activity of a cell is expressed in its proteome. Full understanding of the complexity of cells demands a comprehensive view of the proteome; its interactions, activity states and organization. Comprehensive proteomic approaches applied to peroxisomes have yielded new insights into the organelle and its dynamic interplay with other cellular structures. As technologies and methodologies improve, proteomics hold the promise for new discoveries of peroxisome function and a full description of this dynamic organelle.

Social deprivation and outcomes in colorectal cancer

Background

The aim of this study was to examine the influence of social deprivation on postoperative mortality and length of stay in patients having surgery for colorectal cancer.

Methods

Data were extracted from the Association of Coloproctology of Great Britain and Ireland database of patients presenting between April 2001 and March 2002. The effect of social deprivation, measured by the Townsend score, on 30-day postoperative mortality and length of stay was evaluated by two-level hierarchical regression analysis.

Results

A total of 7290 (86·8 per cent) patients underwent surgery. Operative mortality was 6·7 per cent and median length of stay 11 days. Deprivation indices were significantly higher in patients with Dukes' ‘D’ cancers, undergoing emergency surgery and with higher American Society of Anesthesiologists (ASA) grades (P &lt; 0·005). Worsening deprivation was associated with higher operative mortality and longer stay (P = 0·014). For each unit increase in deprivation, there was 2·9 (95 per cent confidence interval 0·5 to 5·2) per cent increase in 30-day mortality. On multifactorial analysis, social deprivation was an independent predictor of length of stay, but its effect on operative mortality was explained by differences in ASA grade, operative urgency and Dukes' classification.

Conclusion

Social deprivation was an independent risk factor of postoperative length of stay and associated with higher postoperative mortality. These results have important implications for risk modelling of postoperative outcomes.

Histological examination of circular stapled ‘doughnuts’: Questionable routine practice?

BACKGROUND

Left-sided colonic resections are often anastomosed by the use of the circular stapling gun. Most surgeons routinely submit the resulting set of 'doughnuts' for histological examination.

AIM

The aim of this study is to question the need for this practice by providing our own experience of the impact of 'doughnut' submission on patient management.

PATIENTS AND METHODS

Patients who had undergone a stapled anastomosis for colorectal cancer resection (1998-2004) were identified from the department cancer database and clinical records and histopathological reports were reviewed for all cases.

RESULTS

From a consecutive series of 100 sets of doughnuts only two showed histological abnormality (inflammatory change and a metaplastic polyp). Three patients had local recurrence over the follow-up period: 12, 14 and 36 months after surgery. Histological review of the 'doughnuts' in these patients did not show any abnormality. None of the above findings had any influence on subsequent management.

CONCLUSION

Histological examination of the 'doughnuts' has a considerable impact in terms of time and resource use. This study has shown no benefit in performing routine histological examination of the 'doughnuts'.

Long-term results of abdominal salvage surgery following restorative proctocolectomy

BACKGROUND

This study evaluated outcomes of patients who underwent abdominal salvage ileal pouch redo surgery and identified factors associated with pouch failure following restorative proctocolectomy.

METHODS

Data on patients who underwent abdominal salvage surgery in a tertiary referral centre between 1985 and 2003 were collected. Outcomes studied included failure of salvage and bowel function of patients with an intact intestine.

RESULTS

One hundred and twelve patients underwent 117 pouch salvage procedures for ulcerative colitis (86), indeterminate colitis/ulcerative colitis (eight), indeterminate colitis/Crohn's disease (three), familial adenomatous polyposis (ten) and other conditions (five). The most common indications for pouch salvage were intra-abdominal sepsis (45 patients), anastomotic stricture (13) and retained rectal stump (35). Median follow-up was 46 (range 1-147) months. Twenty-four patients (21.4 per cent) experienced pouch failure, the incidence of which increased with time. The pouch failed in all patients with Crohn's disease. Successful salvage at 5 years was significantly associated with non-septic (85 per cent) rather than septic (61 per cent) indications (P = 0.016). Frequency of night-time defaecation and faecal urgency improved after salvage surgery (P = 0.036 and P = 0.016 respectively at 5-year follow-up; n = 32).

CONCLUSION

Abdominal salvage surgery was associated with a failure rate of 21.4 per cent. A successful outcome was less likely when the procedure was carried out for septic compared with non-septic indications. The rate of pouch failure increased with length of follow-up.

Anabolic effects of acellular bone marrow, platelet rich plasma, and serum on equine suspensory ligament fibroblasts in vitro

The purpose of this study was to investigate the response of suspensory ligament fibroblasts (SLF) to in vitro stimulation using acellular bone marrow (ABM), platelet rich plasma (in vitro PRP), and serum as potential treatment modalities for suspensory desmitis. Blood, bone marrow, and suspensory ligaments were collected from five horses. SLF were harvested, grown until confluent, and stimulated with various concentrations of ABM, PRP, equine serum, foetal bovine serum, and medium (control). The responses to the treatments were assessed using a combination of radio-labeling for total protein synthesis and an ELISA for quantification of Cartilage Oligomeric Matrix Protein (COMP) production. Addition of all of the samples resulted in significant increases in COMP and total protein synthesis over controls (P<0.001). ABM caused the greatest increase in both COMP and total protein synthesis by the SLF. Equine ABM, PRP, and serum contain anabolic factors that promote matrix synthesis by SLF in vitro, with ABM having the greatest effect. Application of bone marrow to injured ligaments may enhance healing by providing anabolic factors, other than or in addition to mesenchymal stem cells, which stimulate matrix production.

A comparison of serial halving and the rule of nines as a pre-hospital assessment tool in burns

Following endorsement of serial halving by the Faculty of Pre-Hospital Care of the Royal College of Surgeons of Edinburgh this study aimed to determine whether the technique was comparable to the rule of nines in making initial assessments of body surface area burned. Ten 'casualties' were made up to represent burn victims (range 6-61%). An external panel of six consultants and one specialist registrar in plastic surgery were invited to assess the simulated casualties. They gave individual and a consensus estimate of the burned areas. One hundred and twenty-five members of local emergency services and military paramedical staff were given a brief video and slide presentation describing either the rule of nines or serial halving method of burn area assessment. These techniques were then used to assess the 10 simulated casualties, giving 1250 estimates of burn surface area. The understanding of both techniques appeared adequate in both test groups. Estimates from serial halving and rule of nines groups differed from the assessments of the external panel. No statistical difference was demonstrated between serial halving and the rule of nines as an initial assessment tool when determining disposal. Serial halving has an inherent weakness when assessing certain sizes of burn. The rule of nines requires that the assessor knows and understands the proportionate areas of the body. The mathematics of percentages and fractions appeared to confuse some assessors.

A comprehensive expressed sequence tag linkage map for tiger salamander and Mexican axolotl: enabling gene mapping and comparative genomics in Ambystoma

Expressed sequence tag (EST) markers were developed for Ambystoma tigrinum tigrinum (Eastern tiger salamander) and for A. mexicanum (Mexican axolotl) to generate the first comprehensive linkage map for these model amphibians. We identified 14 large linkage groups (125.5-836.7 cM) that presumably correspond to the 14 haploid chromosomes in the Ambystoma genome. The extent of genome coverage for these linkage groups is apparently high because the total map size (5251 cM) falls within the range of theoretical estimates and is consistent with independent empirical estimates. Unlike most vertebrate species, linkage map size in Ambystoma is not strongly correlated with chromosome arm number. Presumably, the large physical genome size ( approximately 30 Gbp) is a major determinant of map size in Ambystoma. To demonstrate the utility of this resource, we mapped the position of two historically significant A. mexicanum mutants, white and melanoid, and also met, a quantitative trait locus (QTL) that contributes to variation in metamorphic timing. This new collection of EST-based PCR markers will better enable the Ambystoma system by facilitating development of new molecular probes, and the linkage map will allow comparative studies of this important vertebrate group.

Long-term outcomes of restorative proctocolectomy for Crohn's disease and indeterminate colitis

INTRODUCTION

The present study aims to evaluate the short-term and long-term outcomes of patients undergoing restorative proctocolectomy (RPC) for Crohn's disease (CD) and Indeterminate colitis (IC) and to identify factors associated with adverse outcomes.

METHODS

A descriptive study of 52 patients with CD or IC from a total of 1652 patients undergoing primary or salvage RPC in a single tertiary referral centre between 1978 and 2003. Primary outcomes were ileal pouch failure (excision or indefinite diversion), adverse events and functional outcomes (bowel frequency, urgency and continence).

RESULTS

Patients with IC or IC favouring ulcerative colitis (Group 1, n = 26) had a pouch failure rate of 11.5%vs 57.5% for patients with CD or IC favouring CD (Group 2, n = 26). Pouch salvage surgery was undertaken in 15 patients with a 13.3% failure rate. Patients in Group 2 were 2.6 times more likely (95% CI: 0.96-7. No significant differences were evident between CD and IC patients with regards to pelvic sepsis (19.2%vs 15.4%), anastomotic stricture (23.1%vs 21.7%), small bowel obstruction (26.9%vs 26.9%) or pouchitis (15.4%vs 11.5%). The 24-h bowel frequency (7.5 vs 8), faecal urgency, daytime or night time incontinence were similar between patients with CD or IC..17) to develop a pouch-related fistula than patients in Group 1.

DISCUSSION

Crohn's disease and to a great extent indeterminate colitis favouring CD were both associated with high failure rates and postoperative pouch-related fistula rates. Despite these problems, functional outcomes for patients with CD or IC were similar. Patients with IC should remain candidates for RPC but careful pre-operative assessment is advised to exclude clinical signs favouring the diagnosis of CD. The complications associated with failure are extensive and the option of reconstructive surgery in patients with CD should be questioned.

Evolution of salamander life cycles: a major-effect quantitative trait locus contributes to discrete and continuous variation for metamorphic timing

The evolution of alternate modes of development may occur through genetic changes in metamorphic timing. This hypothesis was examined by crossing salamanders that express alternate developmental modes: metamorphosis vs. paedomorphosis. Three strains were used in the crossing design: Ambystoma tigrinum tigrinum (Att; metamorph), wild-caught A. mexicanum (Am; paedomorph), and laboratory Am (paedomorph). Att/Am hybrids were created for each Am strain and then backcrossed to their respective Am line. Previous studies have shown that a dominant allele from Att (met(Att)) and a recessive allele from lab Am (met(lab)) results in metamorphosis in Att/Am hybrids, and met(Att)/met(lab) and met(lab)/met(lab) backcross genotypes are strongly associated with metamorphosis and paedomorphosis, respectively. We typed a molecular marker (contig325) linked to met and found that met(Att)/met(lab) and met(Att)/met(wild) were associated with metamorphosis in 99% of the cases examined. However, the frequency of paedomorphosis was 4.5 times higher for met(lab)/met(lab) than for met(wild)/met(wild). We also found that met(Att)/met(wild) and met(wild)/met(wild) genotypes discriminated distributions of early and late metamorphosing individuals. Two forms of phenotypic variation are contributed by met: continuous variation of metamorphic age and expression of discrete, alternate morphs. We suggest that the evolution of paedomorphosis is associated with genetic changes that delay metamorphic timing in biphasic life cycles.

TRANSVAGINAL SLING USING ACELLULAR HUMAN DERMAL ALLOGRAFT: SAFETY AND EFFICACY IN 253 PATIENTS

PURPOSE

We evaluated the safety and efficacy of using human dermal allograft material for transvaginal slings to treat female stress urinary incontinence (SUI).

MATERIALS AND METHODS

We present a prospective series of 253 patients with SUI treated with a transvaginal sling using a Repliform cadaveric human dermal allograft (LifeCell Corp., The Woodlands, Texas) and a bone anchor fixation kit. Clinical history, urogynecologic examination and videourodynamics were performed preoperatively. Results were assessed by a third party through validated quality of life questionnaires (Incontinence Impact Questionnaire and Urogenital Distress Inventory), overall impression and percent of improvement as perceived by the patients, and pad use. Scheduled followup examination were performed to rule out erosion, infection, obstruction, pain or recurrent incontinence.

RESULTS

Complete followup was available on 234 of 253 patients. Average followup was 18 months. Of the patients 78% were cured or improved according to the questionnaires. The average improvement was 80%. At 18 months of followup incontinence average distress and scores decreased 10 and 7 points, respectively. Complications were de novo urgency in 5% of cases, recurrent SUI in 15% with no cases of persistent SUI, retention in 2% and slow vaginal wall healing in 1.7%. Of 156 patients 51 (22%) had persistent urgency. There were no cases of vaginal or urethral erosion, osteitis pubis or osteomyelitis.

CONCLUSIONS

Our data indicate that use of human dermal allograft for transvaginal slings is associated with low complication rates and favorable outcomes at an average of 18 months of followup.