Biochemical changes caused by decellularization may compromise mechanical integrity of tracheal scaffolds

Tissue-engineered airways have achieved clinical success, but concerns remain about short-term loss of biomechanical properties, necessitating a stent. This study investigated the effect of chemical-enzymatic decellularization on biochemical properties of trachea important for cell attachment and vascularization (fibronectin and laminin) and cartilage matrix homeostasis (type II collagen and glycosaminoglycans (GAG)), as well as biomechanical status. Native trachea was used as a control, and NDC trachea stored in phosphate buffered saline (PBS) in parallel to decellularization was used as a time-matched control. Decellularization removed most cells, but chondrocytes and DNA remained after 25 cycles. Fibronectin was retained throughout the lamina propria and laminin at basement membranes. DNA accumulation along ECM fibres was seen. A decline in soluble collagen was observed in decellularized tissue. GAG content of cartilage rings was reduced, even in PBS control tissue from 20 cycles onwards (p<0.05), but decellularization caused the greatest loss (p<0.01). Tensile strength declined throughout the process, but was significant only at later time points. The data demonstrate that the substantial reduction in GAG might contribute to loss of mechanical integrity of biotracheas. Overcoming structural changes that cause an imbalance in cartilage matrix equilibrium will be necessary to optimize clinical benefit, enabling widespread use of biotracheas.

Abstract P5-10-13: Pre-surgical plasma microRNA pattern defines a biologically distinct triple negative breast cancer (TNBC) occuring in black (B) compared to white (W) women

Background: Black women with triple negative breast cancer have 46% lower survival rates; this may be due to differences in tumor biology. We analyzed presurgical plasma microRNA of white (W) and black (B) women with TNBC enrolled in the breast ovarian tissue bank to detect if differences in the pre-surgical plasma microRNA could be detected in B patients relative to W patients relative to healthy controls.

Aims: MicroRNA in pre-surgical plasma of TNBC W or B was compared to plasma from controls race and age matched controls to assess if differences in plasma and tumor microRNA may explain the survival disparity observed in B. We addressed 2 questions 1) are the patterns in the pre-surgical miRNA profiles different between W and B patients, differences that could explain outcomes discrepancy? 2) What are the miRs changes in patients W or B relative to healthy controls?

Methods: Between 2004 and 2011 plasma miRNAs was measured before, after surgery, during and after chemotherapy in 73 surgical breast cancer patients and 11 age and race matched controls. We also analized miRs in the tumor and benign adjacent breast in 5 specimes. Samples were analyzed using qRT-PCR in the ABI's TaqMan OpenArray Panel for 750 miRs. Samples were spiked with ath-miR-159a and hsa-miR-320 most strongly correlated in its expression to ath-miR-159a through the Pearson correlation coefficient. 2-sample t-test was used for comparisons between means and ANOVA followed by post-hoc test to compare the mean response between subject factors of interest. All tests were 2-tailed; statistical significance was set at p &lt; 0.05.

Results: 44 W and 23 B, mean age at surgery 48 years (range 35–78) and 11 controls – mean age 44 years (range 35–67). Black TNBC patients did not express over 70 % of pre-surgical plasma miRs present in the W pre-surgical plasma. B over-expressed high levels of miR-1244, -190 and -638, which were not detected in any of the W patients (p &lt; 0.005). W patients and controls expressed miRs10a, -190, -502-3p, -548, and -9* not detected in B TNBC patients. White patients over-expressed over 80% of plasma miRs present in controls, while black patients over-expressed only 30% of miRs present in controls (P &lt; 0.005).

Conclusions: Patterns of pre-surgical miR expression are different in B versus W patients with TNBC. In B the presence of TNBC leads to silence in circulating plasma miRs in comparison to W and controls. In W the presence of the tumor increases the miR “chatter”. Black patients have a different “communication” style between host-TNBC when analyzed by the response of plasma microRNA. This difference may call for different treatment protocols for patients. Specific treatment interventions, such as administration of chemotherapy before surgery, in an attempt to increase the microRNA levels in plasma may improve the outcomes of black patients with TNBC.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-10-13.

Cronkhite Canada syndrome with early colorectal carcinoma in a patient

We relate the first case in the Republic of Ireland of Cronkhite Canada Syndrome (CCS). The patient presented with weight loss, alopecia, nail dystrophy, taste disturbance and classic radiologic and endoscopic features of CCS. She continued to dramatically lose weight and early repeat colonoscopy showed the interim development of an invasive sigmoid adenocarcinoma.J

Comparasion of five gene loci (rnpB, 16S rRNA, 16S-23S rRNA, sodA and dnaJ) to aid the molecular identification of viridans-group streptococci and pneumococci

Viridans-group streptococci (VGS) consist of several taxa which historically have been highly diverse. However, at times it may become necessary to have a reliable scheme for the identification of these organisms to the species level. The aim of this study is to compare the ability of five gene loci, namely rnpB, 16S rRNA, 16S-23S rRNA, sodA and dnaJ, to speciate such organisms through a sequence typing-based approach. Reference organisms consisting of six VGS species were compared based on sequence typing, followed by comparison of 31 wild-type respiratory isolates, and showed that employment of sequence typing using the rnpB gene locus was the most specific and reliable. Therefore, the use of rnpB sequencing for the identification of VGS to species level is a reliable and feasible option, based on a single gene target.

Molecular characterisation of the quinolone resistance-determining regions (QRDR) including gyrA, gyrB, parC and parE genes in Streptococcus pneumoniae

Streptococcus pneumoniae is the leading cause of community-acquired pneumonia (CAP). Currently, empirical treatment with quinolones is being used due to the emergence of beta-lactam and macrolide resistance in S. pneumonaie. Although the prevalence of quinolone-resistant S. pneumoniae remains low, increasing numbers of resistant isolates are being seen. Genetic mechanisms leading to fluoroquinolone resistance in pneumococci are complex. This study aims to use molecular methods to characterise all isolates through sequence analysis of their QRDR regions. Thirty-two S. pneumoniae isolates were obtained from nasal swabs from adult and paediatric patients attending local general practices in Northern Ireland. Phenotypic minimum inhibitory concentration (MIC) was determined for Clinical and Laboratory Standards Institute (CLSI) broth microdilution against ciprofloxacin, levofloxacin and norfloxacin. Simultaneously, the QRDR regions of gyrA, gyrB, parC and parE were analysed by sequence typing for all pneumococci obtained. Only one isolate (3.1%) showed reduced susceptibility to ciprofloxacin and levofloxacin. Two amino acid positions were discordant in the S. pneumoniae R6 strain and eight (25%) and 23 (71.9%) isolates contained the mutations Ile460Val in gyrA and Lys137Asn in parC (deposited in GenBank, accession numbers GQ999587-GQ999589), respectively. No mutations were found in either the gyrB or parE loci. In conclusion, the study demonstrated increased fluoroquinolone resistance which could not be accounted for simply through QRDR mutations, and, reciprocally, that mutations in the QRDR region do not necessarily result in overt phenotypic resistance.

P3-11-06: A Pilot Study of RPFNA in Overweight and Obese Postmenopausal Women

Background: Random periareolar fine-needle aspiration (RPFNA) is a research-based procedure used to obtain breast epithelial cells and fluid. Data suggest that atypia in epithelial cells from RPFNA specimens is associated with an increased risk of breast cancer, and changes in the degree of atypia may be a viable biomarker for response to chemopreventive interventions.

Methods: We performed RPFNA on 37 overweight or obese (body mass index (BMI≥ 25.0 kg/m2) postmenopausal (50-75 y) women enrolled in a randomized clinical trial of Vitamin D vs placebo in combination with a lifestyle (diet + exercise)-based weight loss program. Eligibility criteria included serum vitamin D concentrations 10–32 ng/mL. The procedure was performed by two trained clinicians prior to randomization to assess baseline cell counts and degree of atypia. Two areas in the breast (10:00 and 2:00 positions) were infiltrated with lidocaine, and 8 to 10 aspirations of cellular material were performed using 1.5 inch, 21-gauge needles. The aspirated fluid was placed in 9 cc of Cytolyt Thinprep (Hologic Inc.) with 1 cc of 1% neutral buffered formalin and slides were prepared according to the University of Washington Department of Pathology non-gyn protocol.

Results: Thirty-seven women were included in this analysis. The mean age and BMI of study participants was 59.3 years and 32.5 kg/m2, respectively. The mean 5-year Gail risk score for study participants was 1.96%; 52% of women had a 5-year Gail risk &gt;1.66%. Eight participants (21.6%) had &gt;50 cells present on cytology examination. One additional participant had 10–50 cells, and one had &lt;10 cells. No specimens showed cellular atypia. The remainder of study participants had only blood or fibroadipose tissue on cytology specimens. Women with epithelial cells present were younger (mean age 55.0 vs. 60.2 years, p=0.05). There were no significant differences in BMI or Gail risk score between those with and without epithelial cells.

Conclusions: RPFNA in our sample of overweight/obese postmenopausal women did not yield epithelial cells in a majority of participants. Younger age was associated with a greater cell count. We are planning further studies to determine whether other markers in RPFNA specimens can be used to assess breast tissue changes in response to chemopreventive interventions.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-11-06.

Impacts of maintenance dredged material disposal on macrobenthic structure and secondary productivity

The results of a monitoring programme to assess the spatial impacts associated with ongoing dredged material disposal activity at a dispersive, coastal disposal site (southwest UK) are described. Benthic impacts were assessed using benthic community structure and secondary productivity estimates. Analyses of univariate indices (including secondary production) and multivariate community structure revealed differences between stations inside and those outside the disposal site were minimal. Generally, stations within and outside the disposal site were characterised by the same species. Regression models indicated that the variability in biological structure and secondary production was predominantly accounted for by natural variables (e.g., depth, sediment granulometry) with only a small amount of residual variability being due to contaminant variables. Thus, the elevated levels of certain contaminants in the vicinity of the disposal area were not sufficient to result in significant ecological or ecotoxicological changes. We ascribe such findings partly to the dispersive nature of the disposal site.

Prevalence of clustered regulatory interspaced short palindromic repeat (CRISPR)-like sequences in mitis-group streptococci

Clustered regulatory interspaced short palindromic repeats (CRISPRs) have been discovered in many bacteria and archaea. Many CRISPR-like sequences have been identified in an increasing number of studies on the function of CRISPRs. One CRISPR-like sequence of approximately 240 base pairs has been found to be highly conserved within 11 genome sequences of Streptococcus pneumoniae. A specific CRISPR-like polymerase chain reaction (PCR) assay was designed with the novel primers CRISPR 5F (forward primer) 5'-CTA ATY TCA TAA CCA TAR GAA TC-3' and CRISPR 3R (reverse primer) 5'-GAT AAR ATC CTY TAA WCT TCT AG-3' to detect the presence of this CRISPR-like sequence in pneumococci, as well as in viridans-group streptococci (VGS). This study investigates the prevalence of this CRISPR-like sequence in S. pneumoniae and 12 viridans-group streptococcal species and shows its existence to be shared by the majority of S. pneumoniae and, to a lesser extent, S. mitis. This CRISPR-like sequence was also found in S. australis and it is highly conserved among these strains, suggesting possible biological functional differences from true CRISPR because this CRISPR-like sequence has relatively few repeat numbers, and adjacent homology of CRISPR-associated (cas) genes was absent. The sharing of this CRISPR-like sequence between pneumococci, the mitis group and other VGS, as well as its high sequence homology, may suggest close evolutionary emergence of this sequence between these species.

Omega-5 gliadin anaphylaxis: an integrated diagnostic approach

We report the case of a 62-year old man who presented a wheat-dependent, exercise-induced anaphylaxis (WDEIA). The case illustrates the usefulness of skin prick test not only with wheat extract, but also with native gliadin extract. Moreover we confirm the value of recombinant IgE dosage with rTri a 19 omega-5 gliadin in the diagnostic pathway of this condition.

Oxidation–reduction reactions of simple hydroxamic acids and plutonium(IV) ions in nitric acid

Simple hydroxamic acids such as formo- and aceto-hydroxamic acids have been proposed as suitable reagents for the separation of either Pu and/or Np from U in modified or single cycle Purex based solvent extraction processes designed to meet the emerging requirements of advanced fuel cycles. The stability of these hydroxamic acids is dominated by their decomposition through acid hydrolysis. Kinetic studies of the acid hydrolysis of formo- and aceto-hydroxamic acids are reported in the absence and the presence of Pu(IV) ions. The slow reduction of these plutonium(IV) hydroxamate complexes to Pu(III) aquo-ions has been characterised by spectrophotometry and cyclic voltammetry. The reductions of Pu(IV) in the presence of FHA and AHA are consistent with a mechanism in which free hydroxamic acid in solution is hydrolysed whilst Pu(IV) ions remain fully complexed to hydroxamate ligands; then at some point close to a 1 : 1 Pu(IV) : XHA ratio, some free Pu4+ is released from the complex and reduction is initiated. Electrochemical and kinetic data suggest that the reductant is the hydroxamic acid rather than the hydroxylamine.

Multiple novel astrovirus species in human stool

Diarrhoea remains a significant cause of morbidity and mortality in developing countries where numerous cases remain without identified aetiology. Astroviruses are a recently identified cause of animal gastroenteritis which currently includes two species suspected of causing human diarrhoea. Using pan-astrovirus RT-PCR, we analysed human stool samples from different continents for astrovirus-related RNA sequences. We identified variants of the two known human astrovirus species plus, based on genetic distance criteria, three novel astrovirus species all distantly related to mink and ovine astroviruses, which we provisionally named HMOAstV species A-C. The complete genome of species A displayed all the conserved characteristics of mammalian astroviruses. Each of the now three groups of astroviruses found in human stool (HAstV, AstV-MLB and HMOAstV) were more closely related to animal astroviruses than to each other, indicating that human astroviruses may periodically emerge from zoonotic transmissions. Based on the pathogenic impact of their closest phylogenetic relatives in animals, further investigations of the role of HMOAstV, so far detected in Nigeria, Nepal and Pakistan, in human gastroenteritis are warranted.

Preimplantation genetic diagnosis as a source of human embryonic stem cells for disease research and drug discovery

Embryos surplus to therapeutic requirements following preimplantation genetic diagnosis can be used to derive human embryonic stem cell (hESC) lines carrying mutations significant to human disease. These cells provide a powerful in vitro tool for modelling disease progression in a number of cell types as well as having the potential to revolutionise drug discovery. Robust and reproducible directed differentiation protocols are needed to maximise the potential of these cells. In this review, we explore the current use of hESC and induced pluripotent stem cells in disease-specific research and discuss the use of stem cell technology in drug discovery and toxicity testing.

Perceived concepts of continuity of care in people with colorectal and breast cancer--a qualitative case study analysis

We aimed to develop ideas on continuity of cancer care. In-depth qualitative interviews were conducted with 28 people. Seven had cancer. Each person with cancer nominated a close person and a primary and secondary health care professional. We examined from four perspectives: experiences of the initial diagnosis; subsequent treatment; views on continuity of care; information given about the illness; psychological/physical impact of cancer and communication with professionals, family and friends. Perceived continuity of care was influenced by the actions of patients', involvement of close contacts and engagement in shared decision making. Additionally communication between primary and secondary care, the role of various health professionals and hospital administrative systems strongly influenced continuity of care. Informational, management and relational continuity have been previously described. Our data uncovered the effect of patients' actions and the involvement of close friends and families on continuity of cancer care. People with cancer should be enabled to influence continuity of their care. Full recognition of the role of health professionals, different approaches to sharing information with patients and tightening of hospital administrative systems should also be considered.

Macrofaunal recovery following TBT ban. Long-term recovery of subtidal macrofaunal communities in relation to declining levels of TBT contamination

In the United Kingdom, the use of TBT-based anti-fouling paints on small vessels was banned in 1987, and a biological study of the Crouch Estuary, a yachting centre on the south-eastern coast of the UK, was conducted in order to determine the ecological improvements resulting from this legislation. We present the changes in the macro-infaunal communities along the estuary in relation to declining TBT concentrations between 1987 and 2005. Although the major changes in response to the ban were observed within the first 3 years (primarily an increase in the number of crustacean taxa and a shift in community structure), with changes still apparent between three and 5 years, the temporal duration of this study allowed the rapidity of the response to be truly determined.

Building comparative gene expression databases for the mouse preimplantation embryo using a pipeline approach to UniGene

To understand early mammalian development there is a need to compare profiles of gene expression from different stages of the preimplantation mouse embryo. We describe here a method that uses gene expression data held in the UniGene database of the National Institutes of Health (NIH). The full mouse UniGene database (build #151) contains 43,104 gene clusters generated from approximately 4.1 million sequences. The Expressed Sequence Tags (EST) used to build UniGene are derived from cDNA libraries that are archived separately in the database of Expressed Sequence Tags (dbEST) database, with their own catalogue numbers. The mouse dbEST database contains 32 non-normalized dbEST libraries constructed from preimplantation stages (unfertilized oocyte, fertilized oocyte, 2-, 4-, 8- and 16-cell embryo and blastocyst). These libraries contain 219,852 EST sequences mapping to 15,731 UniGene clusters. We have developed a computational pipeline approach that imports and aggregates inventories of gene expression contained in these dbEST libraries. It uses these data to build an annotated web-based database of preimplantation gene expression with an in-built capacity for comparison of expression profiles. Comparison of gene expression profiles obtained for each developmental stage show statistically significant changes in gene expression during preimplantation development. These in silico-generated profiles were validated using RT-PCR.

Use of tunnelled catheters for malignant pleural effusions in patients fit for pleurodesis

The aim of the present study was to examine the effectiveness of tunnelled pleural catheters (TPC) in patients with malignant pleural effusions who would otherwise be candidates for pleurodesis. Patients were selected from a previously reported database of 250 TPC insertions. The study group was selected based on lung re-expansion and survival as a surrogate maker of eligibility for pleurodesis procedure, as defined by survival of > or =90 days and lung re-expansion > or =80% post-drainage on a standard chest radiograph 2 weeks post TPC placement. There were 109 procedures in 97 patients that met the entry criteria. Spontaneous pleurodesis (SP) was achieved following 70% of procedures and correlated with symptom control. The mean time to SP was 90 days. There was no need for a repeat procedure in 87% of cases overall and in 92% of patients experiencing SP. There were few complications and no procedure-related deaths. Tunnelled pleural catheters are an effective way of controlling malignant pleural effusions when used as first-line treatment in patients who appear to be candidates for pleurodesis procedures.

Regenerative medicine. The industry comes of age

The regenerative medicine industry has moved into a new era in which commercialisation and not research is the number one priority. To achieve its new goal, much has had to change, including the introduction of expert business management, simpler but superior products and scalability of manufacture. Mass public and political support is supplying both long-term resources and the market demand to finally create a sustainable new health-care sector.

The Korean stem cell fiasco: shifting the focus

No one could have failed to have seen the dramatic headlines surrounding Professor Woo Suk Hwang of the Seoul National University. Hwang claimed first place in the race to create patient-specific stem cells from cloned human embryos, only to be discredited shortly afterwards. This article discusses whether such high-profile negative publicity has damaged the regenerative medicine industry in general or whether it has merely shifted the stem cell focus away from South Korea.

Ectodermal dysplasia--an unusual dental presentation

Ectodermal dysplasia (ED) is a rare group of disorders affecting the hair, teeth, nails and sweat glands to a variable degree. There is a wide range of clinical presentation of ED. Missing teeth or abnormal tooth form may be the first indicator of the presence of the disorder. There is typically hypodontia with microdontia. We present an unusual case of ED with severe hypodontia and macrodontia affecting all first permanent molar teeth. We also consider the classification and presentation of this disorder.

Other approaches to fighting cardiovascular disease: stem cells and engineered tissue

Technologies such as vessels and cardiac patches grown in the laboratory are being developed to treat heart disease. This article reviews the progress so far with these and other regenerative-medicine products.

Tissue engineering skin: a paradigm shift in wound care

Tissue-engineered skin for the treatment of burns and ulcers is a clinical success, but making it commercially viable is more problematic. This article examines the industry, its techniques and suggests the way forward.

Stem cells are big news, but are they big business?

Future health care will involve treatment with stem cells and tissue engineering. This article, the first in a series reporting on the scientific breakthroughs in this area and relating them to the medical device industry, describes the science.

Correlation between genotype, phenotype and sex of rearing in 111 patients with partial androgen insensitivity syndrome

OBJECTIVE

Partial androgen insensitivity syndrome (PAIS) is a heterogeneous group of intersex disorders characterized by a typical perineoscrotal hypospadias/micropenis phenotype, and a normal androgen-producing testis. Various mutations in the androgen receptor (AR) are known to cause PAIS. Phenotypic expression is widely variable and there are no agreed guidelines to determine the sex of rearing in individuals with borderline masculinization. We aimed to quantitatively assess the external genital phenotype in relation to AR genotype and sex of rearing and identify criteria that differentiate mutation positive (ARmt) from mutation negative (ARwt) PAIS patients.

PATIENTS AND DESIGN

Cases with a diagnosis of PAIS were identified from the Cambridge Intersex Database. An external masculinization score (EMS) was used to quantify the degree of undermasculinization. Family history of AIS and details of the sex of rearing were recorded. Androgen binding was analysed in fibroblasts obtained from genital skin biopsies and mutational analysis of the AR was performed on genomic DNA extracted from peripheral blood. EMS and sex of rearing were compared in cases with similar mutations reported on the McGill International Database.

RESULTS

Two hundred and sixty-three patients with PAIS were identified. Androgen receptor gene sequencing was performed in 111 patients. Twenty-seven (24%) had mutations. Family history of AIS was present in 61 and 21% of ARmt and ARwt patients, respectively. The median EMS was 3 in both groups. The majority of ARmt patients had abnormal binding and there was a tendency to a higher median testosterone rise on hCG stimulation in ARmt (9.3 nmol/l) compared with ARwt patients (6.9 nmol/l). All patients with EMS of 4 or more were raised as male but there was an overlap of sex of rearing in patients with an EMS less than 4. A wide variation of EMS in relation to genotype and sex of rearing was observed.

CONCLUSION

The phenotype in PAIS is extremely variable and is rarely predicted by the AR genotype. Apart from the family history, there are no specific criteria to differentiate ARwt from ARmt. Sex of rearing is not entirely dependent on the EMS. Cultural issues, other modifying genes and response to androgen trials might be influencing factors. Collaborative studies with uniform protocols are needed to investigate infants with PAIS. Documenting phenotype, surgical procedures and outcome criteria are necessary to enable decision-making on the sex of rearing in patients with a lower range EMS.