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1.
Eur J Pediatr ; 182(12): 5625-5635, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37819419

ABSTRACT

The purpose of this study is to examine associations between maternal lipid profiles in pregnancy and offspring growth trajectories in a largely macrosomic cohort. This is a secondary analysis of the ROLO birth cohort (n = 293), which took place in the National Maternity Hospital, Dublin, Ireland. Infants were mostly macrosomic, with 55% having a birthweight > 4 kg. Maternal mean age was 32.4 years (SD 3.9 years), mean BMI was 26.1 kg/m2 (SD 4.4 kg/m2) and 48% of children born were males. Total cholesterol, high density lipoprotein cholesterol (HDL-cholesterol), low density lipoprotein cholesterol (LDL-cholesterol) and triglycerides were measured from fasting blood samples of mothers at 14 and 28 week gestation. The change in maternal lipid levels from early to late pregnancy was also examined. Offspring abdominal circumference and weight were measured at 20- and 34-week gestation, birth, 6 months, 2 years and 5 years postnatal. Linear spline multilevel models examined associations between maternal blood lipid profiles and offspring growth. We found some weak, significant associations between maternal blood lipids and trajectories of offspring growth. Significant findings were close to the null, providing limited evidence. For instance, 1 mmol/L increase in maternal triglycerides was associated with faster infant weight growth from 20- to 34-week gestation (0.01 kg/week, 95% CI - 0.02, - 0.001) and slower abdominal circumference from 2 to 5 years (0.01 cm/week, 95% CI - 0.02, - 0.001). These findings do not provide evidence of a clinically meaningful effect.    Conclusion: These findings raise questions about the efficacy of interventions targeting maternal blood lipid profiles in pregnancies at risk of macrosomia. New studies on this topic are needed. What is Known: • Maternal fat accumulation during early pregnancy may potentially support fetal growth in the third trimester by providing a reserve of lipids that are broken down and transferred to the infant across the placental barrier. • There are limited studies exploring the impact of maternal lipid profiles on infant and child health using growth trajectories spanning prenatal to postnatal life. What is New: • Maternal blood lipid profiles were not associated with offspring growth trajectories of weight and abdominal circumference during pregnancy up to 5 years of age in a largely macrosomic cohort, as significant findings were close to the null, providing limited evidence for a clinically meaningful relationship. • Strengths of this work include the use of infant growth trajectories that span prenatal to postnatal life and inclusion of analyses of the change of maternal lipid levels from early to late pregnancy and their associations with offspring growth trajectories from 20-week gestation to 5 years of age.


Subject(s)
Lipids , Placenta , Male , Infant , Child , Pregnancy , Female , Humans , Adult , Cohort Studies , Birth Weight , Triglycerides , Cholesterol, HDL
2.
Gut Microbes ; 13(1): 1-10, 2021.
Article in English | MEDLINE | ID: mdl-34030582

ABSTRACT

The gut microbiome in patients with colorectal cancer (CRC) is different than that of healthy controls. Previous studies have profiled the CRC tumor microbiome using a single biopsy. However, since the morphology and cellular subtype vary significantly within an individual tumor, the possibility of sampling error arises for the microbiome within an individual tumor. To test this hypothesis, seven biopsies were taken from representative areas on and off the tumor in five patients with CRC. The microbiome composition was strikingly similar across all samples from an individual. The variation in microbiome alpha-diversity was significantly greater between individuals' samples then within individuals. This is the first study, to our knowledge, that shows that the microbiome of an individual tumor is spatially homogeneous. Our finding strengthens the assumption that a single biopsy is representative of the entire tumor, and that microbiota changes are not limited to a specific area of the neoplasm.


Subject(s)
Bacteria/isolation & purification , Colorectal Neoplasms/microbiology , Gastrointestinal Microbiome , Aged , Bacteria/classification , Bacteria/genetics , Biopsy , Colon/microbiology , Colon/pathology , Colorectal Neoplasms/pathology , Female , Humans , Male , Middle Aged , Phylogeny
3.
Br J Surg ; 108(2): 128-137, 2021 03 12.
Article in English | MEDLINE | ID: mdl-33711141

ABSTRACT

BACKGROUND: Mixed results are reported on clinical and cancer outcomes in laparoscopic rectal cancer surgery (LRCS) compared with robotic rectal cancer surgery (RRCS). However, more favourable functional outcomes are reported following RRCS. This study compared urinary and sexual function following RRCS and LRCS in male and female patients. METHODS: A systematic review and meta-analysis of urinary and sexual function after RRCS and LRCS was performed following PRISMA and MOOSE guidelines, and registered prospectively with PROSPERO (ID:CRD42020164285). The functional outcome reporting tools most commonly included: the International Prostate Symptom Score (IPSS), International Index of Erectile Function (IIEF) and Female Sexual Function Index (FSFI). Mean scores and changes in mean scores from baseline were analysed using RevMan version 5.3. RESULTS: Ten studies were included reporting on 1286 patients. Some 672 patients underwent LRCS, of whom 380 (56.5 per cent) were men and 116 (17.3 per cent) were women (gender not specified in 176 patients, 26.2 per cent). A total of 614 patients underwent RRCS, of whom 356 (58.0 per cent) were men and 83 (13.5 per cent) were women (gender not specified in 175 patients, 28.5 per cent). Regarding urinary function in men at 6 months after surgery, IPSS scores were significantly better in the RRCS group than in the LRCS group (mean difference (MD) -1.36, 95 per cent c.i. -2.31 to -0.40; P = 0.005), a trend that persisted at 12 months (MD -1.08, -1.85 to -0.30; P = 0.007). ΔIIEF scores significantly favoured RRCS at 6 months [MD -3.11 (95%CI -5.77, -0.44) P <0.021] and 12 months [MD -2.76 (95%CI -3.63, -1.88) P <0.001] post-operatively. Mixed urinary and sexual function outcomes were reported for women. CONCLUSION: This meta-analysis identified more favourable urinary and erectile function in men who undergo robotic compared with conventional laparoscopic surgery for rectal cancer. Outcomes in women did not identify a consistently more favourable outcome in either group. As robotic rectal cancer surgery may offer more favourable functional outcomes it should be considered and discussed with patients.


Subject(s)
Female Urogenital Diseases/etiology , Laparoscopy/adverse effects , Male Urogenital Diseases/etiology , Rectal Neoplasms/surgery , Robotic Surgical Procedures/adverse effects , Erectile Dysfunction/etiology , Female , Humans , Laparoscopy/methods , Male , Robotic Surgical Procedures/methods , Urination Disorders/etiology
4.
Cell Cycle ; 16(3): 259-270, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28055303

ABSTRACT

Transcriptional timing is inherently influenced by gene length, thus providing a mechanism for temporal regulation of gene expression. While gene size has been shown to be important for the expression timing of specific genes during early development, whether it plays a role in the timing of other global gene expression programs has not been extensively explored. Here, we investigate the role of gene length during the early transcriptional response of human fibroblasts to serum stimulation. Using the nascent sequencing techniques Bru-seq and BruUV-seq, we identified immediate genome-wide transcriptional changes following serum stimulation that were linked to rapid activation of enhancer elements. We identified 873 significantly induced and 209 significantly repressed genes. Variations in gene size allowed for a large group of genes to be simultaneously activated but produce full-length RNAs at different times. The median length of the group of serum-induced genes was significantly larger than the median length of all expressed genes, housekeeping genes, and serum-repressed genes. These gene length relationships were also observed in corresponding mouse orthologs, suggesting that relative gene size is evolutionarily conserved. The sizes of transcription factor and microRNA genes immediately induced after serum stimulation varied dramatically, setting up a cascade mechanism for temporal expression arising from a single activation event. The retention and expansion of large intronic sequences during evolution have likely played important roles in fine-tuning the temporal expression of target genes in various cellular response programs.


Subject(s)
Gene Expression Regulation , Genes , Transcription, Genetic , Animals , Bromouracil/analogs & derivatives , Conserved Sequence , Enhancer Elements, Genetic/genetics , Evolution, Molecular , Fibroblasts/metabolism , Humans , Male , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Models, Biological , Oligonucleotide Array Sequence Analysis , Serum/metabolism , Serum Response Factor/genetics , Serum Response Factor/metabolism , Time Factors , Transcription Factors/metabolism , Uridine/analogs & derivatives , Uridine/metabolism
5.
Colorectal Dis ; 19(2): 123-138, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27317641

ABSTRACT

AIM: The medical management of inflammatory bowel disease (IBD) in pregnancy and the puerperium is well defined. Data on surgical management of complicated IBD in this setting are lacking. This study aimed to determine the optimal surgical strategy for medically refractory IBD during pregnancy and the puerperium. METHOD: Three databases were systematically reviewed to identify all published series or case reports of women undergoing surgery for Crohn's disease (CD) or ulcerative colitis (UC) while pregnant or during the puerperium. RESULTS: Thirty-two papers were identified, including 86 patients. Nearly one-fifth (18%) of cases were de novo presentations and intervention was required at all stages of pregnancy. UC refractory to medical treatment and perforated small bowel CD were the commonest indications for surgery. Operations used included colectomy, colectomy with mucous fistula and Turnbull-blowhole colostomy for complicated UC and open or laparoscopic small bowel resection with stoma formation for CD. Surgical intervention during the third trimester universally resulted in the onset of labour. Endoscopic and radiological interventions were rarely employed. In studies after 1980 there was no maternal or foetal mortality but there was an almost 50% preterm delivery rate. CONCLUSION: Surgical management of complicated IBD during pregnancy and the puerperium needs to be tailored to disease severity, the type of complications and foetal status. It should involve gastroenterologists, colorectal surgeons, obstetricians and neonatal specialists in a multidisciplinary manner within a single unit.


Subject(s)
Colitis, Ulcerative/surgery , Crohn Disease/surgery , Digestive System Surgical Procedures/methods , Postoperative Complications/epidemiology , Pregnancy Complications/surgery , Premature Birth/epidemiology , Colectomy/methods , Enterostomy/methods , Female , Humans , Inflammatory Bowel Diseases/surgery , Intestine, Small/surgery , Laparoscopy , Postpartum Period , Pregnancy
6.
Clin Oncol (R Coll Radiol) ; 29(3): 198-204, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27726909

ABSTRACT

AIMS: Contact radiotherapy for early rectal cancer uses 50 kV X-rays to treat rectal cancers under direct vision. We present data of a series of patients treated at a single centre with prospective follow-up and functional assessment. MATERIALS AND METHODS: All patients were treated at the Queen's Centre for Oncology, Hull, UK between September 2011 and October 2015. Patients received a biopsy, magnetic resonance imaging (MRI) of the liver/pelvis, computed tomography of the chest and endorectal ultrasound. Patients were deemed to be either unfit for radical surgery or refused it due to the need for a permanent stoma. Follow-up consisted of 3 monthly flexible sigmoidoscopy and MRI of the liver/pelvis and 12 monthly computed tomography of the chest. RESULTS: In total, 42 patients were treated with contact radiotherapy ± external beam chemo/radiotherapy without any primary surgical excision. The median age was 78 years (range 50-94 years). Local recurrence-free survival was 88%, disease-free survival was 86% and overall survival was 88% with a median follow-up of 24 months (range 5-54 months). The median time to recurrence was 12 months (range 4-14 months). The estimated 30 day surgical mortality for this cohort with radical surgery was 12%. Mortality from the contact radiotherapy procedure was 0%. Functional outcomes as investigated by the Low Anterior Resection Syndrome (LARS) score were good, with 65% having no LARS. CONCLUSIONS: Contact radiotherapy for early rectal cancer is a safe, well-tolerated outpatient procedure, allowing organ preservation, with excellent oncological and functional outcomes. For elderly co-morbid patients with suitable rectal cancers this should be considered as a standard of care.


Subject(s)
Radiotherapy/methods , Rectal Neoplasms/radiotherapy , Aged , Aged, 80 and over , Disease-Free Survival , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Prospective Studies , Rectal Neoplasms/pathology , Tomography, X-Ray Computed , Treatment Outcome
7.
Biol Open ; 5(6): 837-47, 2016 Jun 15.
Article in English | MEDLINE | ID: mdl-27230646

ABSTRACT

Dynamic regulation of gene expression via signal transduction pathways is of fundamental importance during many biological processes such as cell state transitioning, cell cycle progression and stress responses. In this study we used serum stimulation as a cell response paradigm to apply the nascent RNA Bru-seq technique in order to capture early dynamic changes in the nascent transcriptome. Our data provides an unprecedented view of the dynamics of genome-wide transcription during the first two hours of serum stimulation in human fibroblasts. While some genes showed sustained induction or repression, other genes showed transient or delayed responses. Surprisingly, the dynamic patterns of induction and suppression of response genes showed a high degree of similarity, suggesting that these opposite outcomes are triggered by a common set of signals. As expected, early response genes such as those encoding components of the AP-1 transcription factor and those involved in the circadian clock were immediately but transiently induced. Surprisingly, transcription of important DNA damage response genes and histone genes were rapidly repressed. We also show that RNA polymerase II accelerates as it transcribes large genes and this was independent of whether the gene was induced or not. These results provide a unique genome-wide depiction of dynamic patterns of transcription of serum response genes and demonstrate the utility of Bru-seq to comprehensively capture rapid and dynamic changes of the nascent transcriptome.

8.
Sci Rep ; 5: 17978, 2015 Dec 11.
Article in English | MEDLINE | ID: mdl-26656874

ABSTRACT

BruUV-seq utilizes UV light to introduce transcription-blocking DNA lesions randomly in the genome prior to bromouridine-labeling and deep sequencing of nascent RNA. By inhibiting transcription elongation, but not initiation, pre-treatment with UV light leads to a redistribution of transcription reads resulting in the enhancement of nascent RNA signal towards the 5'-end of genes promoting the identification of transcription start sites (TSSs). Furthermore, transcripts associated with arrested RNA polymerases are protected from 3'-5' degradation and thus, unstable transcripts such as putative enhancer RNA (eRNA) are dramatically increased. Validation of BruUV-seq against GRO-cap that identifies capped run-on transcripts showed that most BruUV-seq peaks overlapped with GRO-cap signal over both TSSs and enhancer elements. Finally, BruUV-seq identified putative enhancer elements induced by tumor necrosis factor (TNF) treatment concomitant with expression of nearby TNF-induced genes. Taken together, BruUV-seq is a powerful new approach for identifying TSSs and active enhancer elements genome-wide in intact cells.


Subject(s)
Enhancer Elements, Genetic , Gene Expression Regulation/radiation effects , Transcription Initiation Site , Ultraviolet Rays , Computational Biology/methods , Databases, Nucleic Acid , Genome, Human , Genomics/methods , Humans , Molecular Sequence Annotation , Transcription Elongation, Genetic/radiation effects , Transcription, Genetic/radiation effects
10.
Genome Res ; 24(6): 896-905, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24714810

ABSTRACT

The rate of transcription elongation plays an important role in the timing of expression of full-length transcripts as well as in the regulation of alternative splicing. In this study, we coupled Bru-seq technology with 5,6-dichlorobenzimidazole 1-ß-D-ribofuranoside (DRB) to estimate the elongation rates of over 2000 individual genes in human cells. This technique, BruDRB-seq, revealed gene-specific differences in elongation rates with a median rate of around 1.5 kb/min. We found that genes with rapid elongation rates showed higher densities of H3K79me2 and H4K20me1 histone marks compared to slower elongating genes. Furthermore, high elongation rates had a positive correlation with gene length, low complexity DNA sequence, and distance from the nearest active transcription unit. Features that negatively correlated with elongation rate included the density of exons, long terminal repeats, GC content of the gene, and DNA methylation density in the bodies of genes. Our results suggest that some static gene features influence transcription elongation rates and that cells may alter elongation rates by epigenetic regulation. The BruDRB-seq technique offers new opportunities to interrogate mechanisms of regulation of transcription elongation.


Subject(s)
Epigenesis, Genetic , Genome, Human , RNA Polymerase II/metabolism , Transcription Elongation, Genetic , Base Composition , DNA Methylation , Exons , Histones/genetics , Histones/metabolism , Humans , MCF-7 Cells , RNA Polymerase II/genetics , Terminal Repeat Sequences
11.
Colorectal Dis ; 16(8): 577-94, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24655722

ABSTRACT

AIM: Complete mesocolic excision (CME) and extended lympha-denectomy (EL) have been proposed as safe procedures for improving colon cancer survival outcomes. The aim of this study was to evaluate the evidence regarding oncological outcomes, morbidity and mortality after such techniques for colon cancer. METHOD: A systematic review of the literature was conducted to evaluate evidence regarding oncological outcomes, morbidity and mortality after CME or EL. Three major databases (PubMed, MEDLINE and the Cochrane Library) were searched. The review included original articles reporting outcomes after CME or EL from January 1950 to July 2012. RESULTS: Twenty-one, predominately retrospective, studies involving 5246 patients (mean age 68.2 years, 56.5% men) were included. Reporting of outcomes was inconsistent. Median follow up was 60 months. The operative mortality rate was 3.2% and the cumulative morbidity rate was 21.5%. The weighted mean local recurrence rate and the 5-year overall and disease-free survival rates were 4.5%, 58.1% and 77.4%, respectively. CONCLUSION: The available data for CME and EL have numerous fundamental limitations that prohibit adoption. Contemporary controlled studies are required before universal recommendation.


Subject(s)
Colonic Neoplasms/mortality , Colonic Neoplasms/surgery , Lymph Node Excision/mortality , Lymph Node Excision/methods , Disease-Free Survival , Female , Humans , Male , Retrospective Studies
12.
Surgeon ; 12(5): 256-62, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24618362

ABSTRACT

BACKGROUND: Small bowel involvement of Clostridium difficile is increasingly encountered. Data on many management aspects are lacking. AIM: To synthesis existing reports and assess the frequency, pathophysiology, outcomes, risk factors, diagnosis and management of C. difficle enteritis. METHODS: A systematic review of the literature was conducted to evaluate evidence regarding frequency, pathophysiology, risk factors, optimal diagnosis, management and outcomes for C. difficle enteritis. Three major databases (PubMed, MEDLINE and the Cochrane Library) were searched. The review included original articles reporting C. difficle enteritis from January 1950 to December 2012. RESULTS: C. difficle enteritis is rare but increasingly encountered. Presentation is variable and distinct predisposing factors include emergency surgery, white race and increased age. Diagnosis generally involves a sensitive but often non specific screening test for C. difficile antigens. Oral metronidazole represents first line therapy and surgery may be required for complications. Outcomes are inconsistent but may be improving. CONCLUSIONS: A high index of clinical suspicion, early diagnosis and treatment are vital. Further prospective studies are needed to determine the significance of asymptomatic small bowel C. difficile infections.


Subject(s)
Clostridioides difficile , Enterocolitis, Pseudomembranous/diagnosis , Enterocolitis, Pseudomembranous/epidemiology , Enterocolitis, Pseudomembranous/physiopathology , Enterocolitis, Pseudomembranous/therapy , Humans , Incidence , Intestine, Small/microbiology , Mortality , Risk Factors
13.
Colorectal Dis ; 15(10): e623-6, 2013.
Article in English | MEDLINE | ID: mdl-24106751

ABSTRACT

AIM: This technical note describes laparoscopic production of a well vascularized, omental flap of adequate size to fill the pelvic floor defect in the course of laparoscopic abdominoperineal resection (LAPR). METHOD: The omentum is laparoscopically mobilized and transposed to the pelvis following full LAPR in three discrete stages. RESULTS: Laparoscopic omental mobilization, transfer and buttressing of a primary perineal repair reduces pelvic dead space and facilitates closure following LAPR with minimal additional operative time or complications and a potential reduction in perineal wound associated morbidity. CONCLUSION: Laparoscopic omental mobilization is technically feasible and provides a safe method to aid perineal wound closure.


Subject(s)
Laparoscopy/methods , Omentum/surgery , Perineum/surgery , Surgical Flaps , Wound Closure Techniques , Humans , Pelvic Floor/surgery
14.
Colorectal Dis ; 15(11): e634-45, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24034172

ABSTRACT

AIM: Abdominoperineal excision (APR) for cancer carries significant morbidity of the perineal wound. An omental pedicle graft has been used to fill the pelvis and limit attendant complications after radical extirpation of the anorectum. A review of the literature was conducted to determine whether omentoplasty following APR reduces perineal wound complications. METHOD: Three major databases (PubMed, MEDLINE and the Cochrane Library) were searched. The review included original articles reporting outcomes after APR and omentoplasty from January 1950 to July 2012. RESULTS: Fourteen studies involving 891 patients (mean age 61 years, 59.8% men) were included. Median follow-up was 13.5 months. A variety of omentoplasty techniques added a median of 20 min to the operating time. The mean rate of primary wound healing was 66.8%, time to wound healing 24 days and weighted mean wound infection rate 14.4% with omentoplasty compared with 50.1%, 79 days and 18.5% in patients having no omentoplasty. CONCLUSION: Omental mobilization, transfer and buttressing of primary perineal repair following proctectomy reduces perineal wound morbidity with minimal additional operating time or flap-associated morbidity.


Subject(s)
Omentum/surgery , Perineum/surgery , Postoperative Complications/etiology , Rectal Neoplasms/surgery , Surgical Flaps , Wound Closure Techniques , Wound Healing , Humans , Length of Stay , Operative Time , Reoperation , Time Factors
15.
World J Surg ; 37(11): 2700-4, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23982778

ABSTRACT

BACKGROUND: The incidence and consequence of an anastomotic leak associated with low anterior resection for cancer mandates covering stoma in most cases. A water-soluble enema is often performed to assess anastomotic integrity prior to stoma reversal. The functional outcome following reversal in patients with occult radiologically detected leaks is poorly defined. The goal of the present study was to determine the functional outcome in patients with a radiologically detected anastomotic leak who subsequently underwent stoma reversal. METHODS: This case control study used patients with and without radiologically detected occult anastomotic leak having undergone reversal of covering stomata. The study group was matched with controls for age, gender, procedure, tumor stage, and adjuvant/neoadjuvant therapy. Validated fecal incontinence quality of life (FIQL), Cleveland Clinic Fecal Incontinence Score (CCFIS), and the Memorial Sloan-Kettering Cancer Center (MSKCC) Bowel Function Index (BFI) were used. Patient satisfaction, medication use, and ancillary procedures prior to closure were also recorded. RESULTS: Thirteen patients with radiologically detected occult anastomotic leaks and 13 matched controls were identified from a prospectively maintained database. The FIQL, CCFIS, and MSKCC BFI scores were significantly reduced in those with occult leaks. The mean number of radiological and surgical interventions was significantly greater in the patients with occult leaks. Antidiarrheal and bulking agent use, as well as patient satisfaction, were the same for both groups. Only one patient in the occult leak group would not undergo stoma reversal again. CONCLUSIONS: Reversal of a defunctioning ileostomy in the presence of an occult radiological leak can be associated with poorer functional outcomes, but patient satisfaction is undiminished.


Subject(s)
Anastomotic Leak/diagnostic imaging , Rectal Neoplasms/surgery , Aged , Aged, 80 and over , Anastomotic Leak/epidemiology , Case-Control Studies , Digestive System Surgical Procedures , Enema , Fecal Incontinence , Female , Humans , Male , Middle Aged , Neoplasm Staging , Patient Satisfaction , Postoperative Complications/epidemiology , Prospective Studies , Quality of Life , Radiography , Reoperation , Treatment Outcome
16.
J Am Chem Soc ; 132(38): 13126-8, 2010 Sep 29.
Article in English | MEDLINE | ID: mdl-20812737

ABSTRACT

Sensitive, inexpensive, and rapid protease activity assays are of great merit for clinical diagnostics. Detection of protease-based toxins produced by Clostridium botulinum and Bacillus anthracis represents a particularly challenging task, as exceptional sensitivity is a prerequisite because of the extreme potency of the toxins. Here we present an inexpensive and sensitive assay platform for activity-based protease quantification utilizing filamentous bacteriophage as an exponentially amplifiable reporter and its application to the detection of these bacterial toxins. The assay is based on specific cleavage of bacteriophage from a solid support and its subsequent quantification by means of infectivity or quantitative PCR. Detection of botulinum neurotoxin (BoNT) serotypes A and B and anthrax lethal factor in the picomolar range was demonstrated with a limit of detection of 2 pM for BoNT/A under optimized conditions.


Subject(s)
Bacteriophages/chemistry , Peptide Hydrolases/analysis , Limit of Detection , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
17.
Br J Cancer ; 100(10): 1589-602, 2009 May 19.
Article in English | MEDLINE | ID: mdl-19436306

ABSTRACT

Perioperative exposure to lipopolysaccharide (LPS) is associated with accelerated metastatic colorectal tumour growth. LPS directly affects cells through Toll-like receptor 4 (TLR-4) and the transcription factor NF-kappaB. The urokinase plasminogen activator (u-PA) system is intimately implicated in tumour cell extracellular matrix (ECM) interactions fundamental to tumour progression. Thus we sought to determine if LPS directly induces accelerated tumour cell ECM adhesion and invasion through activation of the u-PA system and to elucidate the cellular pathways involved. Human colorectal tumour cell lines were stimulated with LPS. u-PA concentration, u-PA activity, active u-PA, surface urokinase plasminogen activator receptor (u-PAR) and TLR-4 expression were assessed by ELISA, colorimetric assay, western blot analysis and flow cytometry respectively. In vitro tumour cell vitronectin adhesion and ECM invasion were analysed by vitronectin adhesion assay and ECM invasion chambers. u-PA and u-PAR function was inhibited with anti u-PA antibodies or the selective u-PA inhibitors amiloride or WXC-340, TLR-4 by TLR-4-blocking antibodies and NF-kappaB by the selective NF-kappaB inhibitor SN-50. LPS upregulates u-PA and u-PAR in a dose-dependent manner, enhancing in vitro tumour cell vitronectin adhesion and ECM invasion by >40% (P<0.01). These effects were ameliorated by u-PA and u-PAR inhibition. LPS activates NF-kappaB through TLR-4. TLR-4 and NF-kappaB inhibition ameliorated LPS-enhanced u-PA and u-PAR expression, tumour cell vitronectin adhesion and ECM invasion. LPS promotes tumour cell ECM adhesion and invasion through activation of the u-PA system in a TLR-4- and NF-kappaB-dependent manner.


Subject(s)
Bacterial Toxins/pharmacology , Carcinoma/pathology , Colorectal Neoplasms/pathology , NF-kappa B/physiology , Toll-Like Receptor 4/physiology , Urokinase-Type Plasminogen Activator/metabolism , Amiloride/pharmacology , Antibodies/pharmacology , Caco-2 Cells , Carcinoma/metabolism , Cell Adhesion/drug effects , Cell Movement/drug effects , Colorectal Neoplasms/metabolism , Humans , Lipopolysaccharides/pharmacology , NF-kappa B/metabolism , Neoplasm Invasiveness , Receptors, Urokinase Plasminogen Activator/antagonists & inhibitors , Receptors, Urokinase Plasminogen Activator/metabolism , Receptors, Urokinase Plasminogen Activator/physiology , Toll-Like Receptor 4/antagonists & inhibitors , Toll-Like Receptor 4/metabolism , Tumor Cells, Cultured , Urokinase-Type Plasminogen Activator/physiology
18.
Ir J Med Sci ; 177(3): 217-20, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18584276

ABSTRACT

BACKGROUND: Ruptured abdominal aortic aneurysm (RAAA) presents with increased frequency in the winter and spring months. Seasonal changes in atmospheric pressure mirrors this pattern. AIM: To establish if there was a seasonal variation in the occurrence of RAAA and to determine if there was any association with atmospheric pressure changes. METHODS: A retrospective cohort-based study was performed. Daily atmospheric pressure readings for the region were obtained. RESULTS: There was a statistically significant monthly variation in RAAA presentation with 107 cases (52.5%) occurring from November to March. The monthly number of RAAA and the mean atmospheric pressure in the previous month were inversely related (r = -0.752, r (2) = 0.566, P = 0.03), and there was significantly greater daily atmospheric pressure variability on days when patients with RAAA were admitted. CONCLUSION: These findings suggest a relationship between atmospheric pressure and RAAA.


Subject(s)
Aortic Aneurysm, Abdominal/epidemiology , Aortic Rupture/epidemiology , Atmospheric Pressure , Seasons , Chi-Square Distribution , Humans , Incidence , Ireland/epidemiology , Retrospective Studies
19.
Drug News Perspect ; 21(2): 107-16, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18389102

ABSTRACT

The urokinase plasminogen activator (uPA) system is an endogenous proteolytic cascade which can be actively subverted by the neoplastic process to facilitate progression and metastasis. Abundant experimental and clinical evidence supports such a role and elevated levels of components of the uPA system are strong negative prognosis indicators in a wide variety of tumor types. Collectively this data makes the uPA system an attractive option for targeted intervention. This review examines the role of the uPA system in tumor invasion and metastasis and assess the various therapeutic modalities developed to selectively exploit this system.


Subject(s)
Antineoplastic Agents/pharmacology , Neoplasms/drug therapy , Urokinase-Type Plasminogen Activator/drug effects , Animals , Disease Progression , Drug Delivery Systems , Humans , Neoplasm Invasiveness/physiopathology , Neoplasm Invasiveness/prevention & control , Neoplasm Metastasis/drug therapy , Neoplasm Metastasis/physiopathology , Neoplasms/physiopathology , Receptors, Cell Surface/metabolism , Receptors, Urokinase Plasminogen Activator , Urokinase-Type Plasminogen Activator/metabolism
20.
Br J Cancer ; 96(2): 262-8, 2007 Jan 29.
Article in English | MEDLINE | ID: mdl-17242699

ABSTRACT

The urokinase plasminogen activator (u-PA) is intimately associated with tumour invasion and metastases. Surgery facilitates accelerated metastatic tumour growth in murine models, a phenomenon related to elevated perioperative bacterial lipopolysaccaride (LPS) and inflammatory cytokine levels. The objectives of the study were to examine the role of u-PA in cytokine-enhanced tumour cell invasion in vitro and surgery-induced accelerated metastatic tumour growth in vivo and to assess the potential benefit of a novel selective u-PA inhibitor WXC-340 in this setting. CT-26 murine colorectal carcinoma cells were stimulated with LPS, tumour necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6). Cell supernatant u-PA expression and activity were determined using a colorimetric assay and Western blot analysis, respectively. Baseline and cytokine-stimulated in vitro invasion were assessed using ECmatrix invasion chambers. Two established murine models of accelerated metastatic tumour growth were used to investigate the consequences of u-PA inhibition on postoperative metastatic tumour burden. The effect of u-PA inhibition in vitro and in vivo was examined using the novel selective u-PA inhibitor, WXC-340. Proinflammatory cytokine stimulation significantly enhanced in vitro u-PA expression, activity and extracellular matrix invasion by approximately 50% compared to controls (P<0.05). This was abrogated by WXC-340. In vivo WXC-340 almost completely ameliorated both LPS- and surgery-induced, metastatic tumour growth compared to controls (P>0.05). In conclusion, u-PA cascade is actively involved in cytokine-mediated enhanced tumour cell invasion and LPS and surgery-induced metastatic tumour growth. Perioperative u-PA inhibition with WXC-340 may represent a novel therapeutic paradigm.


Subject(s)
Cell Division/drug effects , Endotoxins/pharmacology , Enzyme Inhibitors/pharmacology , Neoplasm Metastasis/prevention & control , Neoplasms, Experimental/surgery , Serine Proteinase Inhibitors/pharmacology , Urokinase-Type Plasminogen Activator/antagonists & inhibitors , Animals , Cell Line, Tumor , Cytokines/blood , Enzyme Inhibitors/toxicity , Female , Mice , Mice, Inbred BALB C , Neoplasms, Experimental/pathology , Serine Proteinase Inhibitors/toxicity
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