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1.
J Pediatr Gastroenterol Nutr ; 76(6): 749-755, 2023 06 01.
Article in English | MEDLINE | ID: mdl-36800276

ABSTRACT

OBJECTIVES: High rates of inflammatory bowel disease (IBD) are reported in children of South Asian (SA) descent in some western countries. This population-based study describes the incidence and clinical course of IBD in SA children compared to non-South Asian (NSA) children in New Zealand (NZ). METHODS: Children (≤15 years) with new-onset IBD presenting to a centralized tertiary referral center in Auckland, NZ from 2010 to 2020 were identified. Disease phenotype, clinical characteristics, response to exclusive enteral nutrition, clinical remission rates at 3 and 12 months, biologic use, corticosteroid exposure, and disease complications were compared by ethnicity; IBD incidence was calculated. RESULTS: There were 127 (26 SA; 101 NSA) children with Crohn disease, 41 (10 SA; 31 NSA) with ulcerative colitis, and 10 (3 SA; 7 NSA) with IBD-unclassified. IBD incidence in SA and NSA children was 14.1 per 100,000 and 4.3 per 100,000 respectively ( P < 0.001). IBD incidence increased by 5.6% per year ( P = 0.022), due to a greater rise in incidence in SA (SA 16.8% per year, P = 0.015; NSA 4.5% per year, P = 0.317). At presentation, SA children had worse biochemical parameters, severe colitis, and vitamin D deficiency. SA children had lower rates of remission following exclusive enteral nutrition (28.5% vs 65.0%, P < 0.001) or biologic induction (35.7% vs 70.8%, P = 0.020), at 3-month (35.3% vs 69.8%, P < 0.001) and 12-month follow-up (29.4% vs 55.0%, P = 0.005). No significant differences were found in disease location or corticosteroid burden. CONCLUSIONS: Increasing incidence of IBD was disproportionately represented by SA children with more severe disease and lower remission rates following exclusive enteral nutrition or biologic therapy.


Subject(s)
Biological Products , Colitis, Ulcerative , Inflammatory Bowel Diseases , Humans , Retrospective Studies , Incidence , New Zealand/epidemiology , Inflammatory Bowel Diseases/therapy , Inflammatory Bowel Diseases/drug therapy , Colitis, Ulcerative/epidemiology , Colitis, Ulcerative/therapy , Colitis, Ulcerative/complications , Adrenal Cortex Hormones/therapeutic use , Biological Products/therapeutic use
2.
Kidney Int ; 99(1): 75-85, 2021 01.
Article in English | MEDLINE | ID: mdl-32949550

ABSTRACT

Targeted therapies and immune checkpoint inhibitors have advanced the treatment landscape of Renal Cell Carcinoma (RCC) over the last decade. While checkpoint inhibitors have demonstrated survival benefit and are currently approved in the front-line and second-line settings, primary and secondary resistance is common. A comprehensive understanding of the mechanisms of immune evasion in RCC is therefore critical to the development of effective combination treatment strategies. This article reviews the current understanding of the different, yet coordinated, mechanisms adopted by RCC cells to evade immune killing; summarizes various aspects of clinical translation thus far, including the currently registered RCC clinical trials exploring agents in combination with checkpoint inhibitors; and provides perspectives on the current landscape and future directions for the field.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Biology , Carcinoma, Renal Cell/drug therapy , Forecasting , Humans , Immune Evasion , Immunotherapy , Kidney Neoplasms/drug therapy
3.
J Surg Res ; 260: 251-258, 2021 04.
Article in English | MEDLINE | ID: mdl-33360691

ABSTRACT

BACKGROUND: Fascial closure significantly reduces postoperative complications and hernia recurrence after abdominal wall reconstruction (AWR), but can be challenging in massive ventral hernias. METHODS: A prospective single-institution cohort study was performed to examine the effects of preoperative injection of botulinum toxin A (BTA) in patients undergoing AWR for midline or flank hernias. RESULTS: A total of 108 patients underwent BTA injection with average 243 units, mean 32.5 days before AWR, without complications. Comorbidities included diabetes (31%), history of smoking (27%), and obesity (mean body mass index 30.5 ± 7.7). Hernias were recurrent in 57%, massive (mean defect width 15.3 ± 5.5 cm; hernia sac volume 2154 ± 3251 cm3) and had significant loss of domain (mean 46% visceral volume outside abdominal cavity). Contamination was present in 38% of patients. Fascial closure was achieved in 91%, with 57% requiring component separation techniques (CSTs). Subxiphoidal hernias needed a form of CST in 88% compared with 50% for hernia not extending subxiphoidal (P < 0.001). Mesh augmentation was used in 98%. Postoperative complications occurred in 40%: 19% surgical site occurrences, 12% surgical site infections, and 7% respiratory failure requiring intubation, 2% mesh infection and no fascial dehiscence. Recurrence was identified in seven patients after mean 14 months of follow-up. Patients undergoing AWR with CST had more surgical site occurrences (29 versus 7%, p0.003) and respiratory failures (18 versus 0%, P = 0.002) than patients who did not require CST. CONCLUSIONS: In patients with massive ventral hernias, the use of preoperative BTA injections for AWR is safe and is associated with high fascial closure rates and excellent recurrence rates.


Subject(s)
Abdominal Wall/surgery , Botulinum Toxins, Type A/therapeutic use , Hernia, Ventral/surgery , Herniorrhaphy/methods , Neuromuscular Agents/therapeutic use , Postoperative Complications/prevention & control , Preoperative Care/methods , Abdominal Wound Closure Techniques , Adult , Aged , Female , Follow-Up Studies , Humans , Injections, Intramuscular , Male , Middle Aged , Postoperative Complications/epidemiology , Prospective Studies , Recurrence , Secondary Prevention , Wound Healing
4.
Skeletal Radiol ; 50(1): 1-7, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32621063

ABSTRACT

Ventral hernias represent the most common complication after abdominal surgery. Loss of domain and/or large ventral hernias in patients are especially challenging for surgeons to manage, but preoperative image-guided botulinum toxin injection has emerged as an effective adjunct to abdominal wall surgery. Loss of domain is caused by chronic muscle retraction of the lateral abdominal wall and leads to an irreducible protrusion of abdominal viscera into the hernia sac. Botulinum toxin can be used in the oblique muscles as a chemical component relaxation technique to aid abdominal wall reconstruction. Intramuscular botulinum toxin injection causes functional denervation by blocking neurotransmitter acetylcholine release resulting in flaccid paralysis and elongation of lateral abdominal wall muscles, increasing the rate of fascial closure during abdominal wall reconstruction, and decreasing recurrence rates. In total, 200-300 units of onabotulinumtoxinA (Botox®) or 500 units of abobotulinumtoxinA (Dypsort®) in a 2:1 dilution with normal saline is most commonly used. Botulinum toxin can be injected with ultrasonographic, EMG, or CT guidance. Injection should be performed at least 2 weeks prior to abdominal wall reconstruction, for maximal effect during surgery. At minimum, botulinum toxin should be injected into the external and internal oblique muscles at three separate sites bilaterally for a total of six injections. Although botulinum toxin use for abdominal wall reconstruction is currently not indicated by the Food and Drug Administration, it is safe with only minor complications reported in literature.


Subject(s)
Abdominal Wall , Neuromuscular Agents , Abdominal Wall/diagnostic imaging , Abdominal Wall/surgery , Herniorrhaphy , Humans , Preoperative Care , Surgical Mesh
5.
Med J Aust ; 212(1): 40-44, 2020 01.
Article in English | MEDLINE | ID: mdl-31834639

ABSTRACT

Gastro-oesophageal reflux (GOR) in infancy is common, physiological and self-limiting; it is distinguished from gastro-oesophageal reflux disease (GORD) by the presence of organic complications and/or troublesome symptomatology. GORD is more common in infants with certain comorbidities, including history of prematurity, neurological impairment, repaired oesophageal atresia, repaired diaphragmatic hernia, and cystic fibrosis. The diagnosis of GORD in infants relies almost exclusively on clinical history and examination findings; the role of invasive testing and empirical trials of therapy remains unclear. The assessment of infants with vomiting and regurgitation should seek out red flags and not be attributed to GOR or GORD without considered evaluation. Investigations should be considered to exclude other pathology in infants referred with suspected GORD, and occasionally to confirm the diagnosis. Management of GORD should follow a step-wise approach that uses non-pharmacological options where possible and pharmacological interventions only where necessary.


Subject(s)
Gastroesophageal Reflux/diagnosis , Gastroesophageal Reflux/therapy , Diagnosis, Differential , Humans , Infant , Infant, Newborn , Infant, Premature , Practice Guidelines as Topic
6.
J Paediatr Child Health ; 56(11): 1719-1723, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32463559

ABSTRACT

Primary intestinal lymphangiectasia is an uncommon condition that usually presents early in childhood. This incurable condition is consequent to underlying lymphatic abnormalities that lead to loss of lymphatic contents into the intestinal lumen. This article outlines an approach to the assessment of children presenting with characteristic features and consideration of other conditions that could lead to enteric protein loss. An overview of the management of primary intestinal lymphangiectasia is outlined.


Subject(s)
Lymphangiectasis, Intestinal , Child , Humans , Intestine, Small , Lymphangiectasis, Intestinal/diagnosis
7.
J Pediatr ; 210: 134-140, 2019 07.
Article in English | MEDLINE | ID: mdl-31036410

ABSTRACT

OBJECTIVES: To evaluate clinical, endoscopic, and pH-impedance measures in a cohort of children with esophageal atresia and concomitant eosinophilic esophagitis (EoE) and compared it with disease-matched controls, to identify predictive factors for the development of EoE and esophageal stricture. STUDY DESIGN: We reviewed 63 patients with esophageal atresia assessed for refractory upper gastrointestinal symptoms between January 2015 and September 2017 at 2 tertiary referral centers. All patients underwent upper gastrointestinal endoscopy and pH-impedance monitoring. Based on esophageal histology, patients were classified as (1) esophageal atresia without evidence of esophagitis; (2) esophageal atresia with evidence of esophagitis (including esophageal eosinophilia not meeting the criteria for EoE); (3) esophageal atresia with concomitant EoE. Age and sex matched patients with gastroesophageal reflux disease were used as disease controls. RESULTS: The presence of atopy and peripheral eosinophilia at baseline were significantly associated with EoE (P < .05). Although there was a tendency toward an increased number of strictures in patients with esophageal atresia-EoE, this did not reach statistical significance (P = .06). Higher esophageal acid exposure time and lower baseline impedance values were significantly associated with eosinophilic infiltration (P < .05 and P < .01, respectively). Using logistic regression analysis, the presence of mucosal eosinophilia was the most predictive factor for stricture formation (P < .05). CONCLUSIONS: A history of atopy and the presence of peripheral eosinophilia in patients with esophageal atresia are predictive factors for the development of EoE, which in turn is a predictive factor for stricture occurrence. Higher esophageal acid exposure time and lower baseline impedance are associated with esophageal eosinophilic infiltration, suggesting their value in selecting which patients with esophageal atresia should undergo endoscopic examination.


Subject(s)
Electric Impedance , Eosinophilic Esophagitis/diagnosis , Esophageal Atresia/epidemiology , Esophageal pH Monitoring , Adolescent , Australia/epidemiology , Case-Control Studies , Child , Child, Preschool , Eosinophilic Esophagitis/epidemiology , Esophageal Stenosis/diagnosis , Esophagoscopy , Female , Humans , Hypersensitivity/epidemiology , Infant , Male , United Kingdom/epidemiology , Young Adult
8.
J Pediatr Gastroenterol Nutr ; 69(1): e7-e12, 2019 07.
Article in English | MEDLINE | ID: mdl-30921259

ABSTRACT

OBJECTIVES: Clinical symptom evaluation for children with inflammatory bowel disease (IBD) is typically done using composite tools: the Pediatric Crohn's Disease Activity Index (PCDAI) and Pediatric Ulcerative Colitis Activity Index (PUCAI). Both rely on clinician interpretation of child or parent symptom recall. No universal self-report tool has yet been developed for children with IBD to assess and report their symptoms. The research objective was to develop a self-report tool that produced information congruent with that obtained by clinicians using the PUCAI or PCDAI. METHODS: A children's symptom self-report tool (IBDnow) was developed with picture and text Likert symptom scales. The clinician and child completed their reports during the same outpatient consultation. Agreement levels were calculated at the individual level (identical child and clinician answers), category level (symptom severity), and aggregate level (cohort scores). Internal consistency was measured with Cronbach alpha. RESULTS: One hundred children from Christchurch (New Zealand) (n = 65), and Sydney (Australia) (n = 35) completed the study (Crohn's Disease (CD):88, ulcerative colitis (UC):12), mean age 13.9 years (±3.6). Mean individual agreement was 0.76 (±0.19). Category severity had very good or good inter-rater reliability for 5 of the 7 symptom scales and overall severity agreement of 76%. Aggregate mean scores were significantly different between clinicians (14.9, ±18.8), and participants (21.6, ±19.4), (P <0.005, confidence interval -9.0, -4.4), but 60 pairs had scores within a 10% margin. Cronbach alpha was 0.74. CONCLUSIONS: This self-report tool had good proportionate agreement between raters, and good crude agreement for symptom categories. Assigning PUCAI or PCDAI scores caused inter-rater discrepancies to be misleadingly magnified. Pediatric gastroenterologists may consider utilizing IBDnow to elicit symptom self-reports from children with IBD to enable them to communicate meaningful information on their ongoing symptom burden. This would be a positive step in helping children feel included in clinical encounters and promoting self-management, at the same time producing valid, subjective symptom recall.


Subject(s)
Colitis, Ulcerative/diagnosis , Crohn Disease/diagnosis , Self Report/standards , Child , Child, Preschool , Female , Humans , Male , Reproducibility of Results , Severity of Illness Index
9.
J Biol Chem ; 292(3): 837-846, 2017 01 20.
Article in English | MEDLINE | ID: mdl-27909050

ABSTRACT

Clear cell renal cell carcinoma (CCRCC) is an incurable malignancy in advanced stages and needs newer therapeutic targets. Transcriptomic analysis of CCRCCs and matched microdissected renal tubular controls revealed overexpression of NOTCH ligands and receptors in tumor tissues. Examination of the TCGA RNA-seq data set also revealed widespread activation of NOTCH pathway in a large cohort of CCRCC samples. Samples with NOTCH pathway activation were also clinically distinct and were associated with better overall survival. Parallel DNA methylation and copy number analysis demonstrated that both genetic and epigenetic alterations led to NOTCH pathway activation in CCRCC. NOTCH ligand JAGGED1 was overexpressed and associated with loss of CpG methylation of H3K4me1-associated enhancer regions. JAGGED2 was also overexpressed and associated with gene amplification in distinct CCRCC samples. Transgenic expression of intracellular NOTCH1 in mice with tubule-specific deletion of VHL led to dysplastic hyperproliferation of tubular epithelial cells, confirming the procarcinogenic role of NOTCH in vivo Alteration of cell cycle pathways was seen in murine renal tubular cells with NOTCH overexpression, and molecular similarity to human tumors was observed, demonstrating that human CCRCC recapitulates features and gene expression changes observed in mice with transgenic overexpression of the Notch intracellular domain. Treatment with the γ-secretase inhibitor LY3039478 led to inhibition of CCRCC cells in vitro and in vivo In summary, these data reveal the mechanistic basis of NOTCH pathway activation in CCRCC and demonstrate this pathway to a potential therapeutic target.


Subject(s)
Kidney Neoplasms/metabolism , Neoplasm Proteins/metabolism , Receptor, Notch1/metabolism , Signal Transduction , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/metabolism , Animals , Carcinoma, Renal Cell , CpG Islands , DNA Methylation , DNA, Neoplasm/genetics , DNA, Neoplasm/metabolism , Female , Humans , Jagged-1 Protein/genetics , Jagged-1 Protein/metabolism , Kidney Neoplasms/drug therapy , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Male , Mice , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/genetics , Protease Inhibitors/pharmacology , Receptor, Notch1/genetics
10.
J Pediatr Gastroenterol Nutr ; 66(2): e45-e50, 2018 02.
Article in English | MEDLINE | ID: mdl-28727653

ABSTRACT

BACKGROUND: The incidence of paediatric inflammatory bowel disease (IBD) around the world is increasing. Canterbury, New Zealand, has one of the highest Crohn disease (CD) incidence rates published. The present study aimed to document the incidence of paediatric IBD in Canterbury between 1996 and 2015. METHODS: All patients diagnosed with IBD in Canterbury, while younger than 16 years, between January 1, 1996 and December 31, 2015 were identified. Demographic and disease phenotypic details were collected and entered into a secure database. Age-specific population data for Canterbury were obtained and annual incidence rates were then calculated. RESULTS: The mean annual incidence rate over the 20-year period was 7.18/100,000 (95% confidence interval 5.55-8.81) children. There was a 4-fold increase in the incidence of paediatric IBD in Canterbury between 1996 and 2015. The ratio of CD to ulcerative colitis (UC) diagnosed was 8.4:1. Disease phenotype of CD and UC, based on the Paris classification, were comparable with other studies. CONCLUSIONS: The incidence of paediatric IBD in Canterbury has increased dramatically during the last 2 decades. Some of the observed incidence rates are among the highest documented anywhere in the world. The preponderance of CD over UC in the present study is the highest published.


Subject(s)
Inflammatory Bowel Diseases/epidemiology , Adolescent , Child , Databases, Factual , Female , Humans , Incidence , Inflammatory Bowel Diseases/surgery , Male , New Zealand/epidemiology , Phenotype
11.
J Pediatr Gastroenterol Nutr ; 66(5): e122-e126, 2018 05.
Article in English | MEDLINE | ID: mdl-29077643

ABSTRACT

BACKGROUND: The global incidence of paediatric inflammatory bowel disease (IBD) is increasing. Much of the evidence attesting to this has arisen from North America and Europe. There is a relative paucity of information on the epidemiology of paediatric IBD in the Southern Hemisphere. The present study aimed to document the prospectively collected incidence of paediatric IBD in New Zealand in 2015. METHODS: All patients younger than 16 years of age and diagnosed with IBD in New Zealand between 1 January 2015 and 31 December 2015 were identified. Demographic and disease phenotypic details were collected and entered into a secure database. Age-specific population data for New Zealand were obtained and national incidence rates for IBD and its subtypes were calculated. RESULTS: The prospectively calculated incidence of paediatric IBD, Crohn disease, ulcerative colitis (UC), and IBD unclassified in New Zealand in 2015 were 5.2 (95% confidence interval 3.9-6.8), 3.5 (2.4-4.8), 1.0 (0.5-1.8), and 0.7 (0.3-1.4) per 100,000 children, respectively. CONCLUSIONS: Incidence rates of paediatric IBD in New Zealand are comparable to the highest rates published in the literature from Western Europe and North America. Ongoing prospective ascertainment of the incidence of paediatric IBD is required to better understand the environmental factors, which are accounting for this increase in disease burden.


Subject(s)
Inflammatory Bowel Diseases/epidemiology , Adolescent , Child , Child, Preschool , Databases, Factual , Female , Humans , Incidence , Infant , Male , New Zealand/epidemiology , Prospective Studies
13.
J Pediatr Gastroenterol Nutr ; 65(3): 311-313, 2017 09.
Article in English | MEDLINE | ID: mdl-28118290

ABSTRACT

Inflammatory bowel disease (IBD) affects many children and adolescents in terms of their confidence, acceptance, and ability to build friendships. New Zealand held its first summer camp for children with IBD in January 2015. We obtained feedback from the campers (ages 10-18 years) in terms of their confidence, acceptance, and quality of life. We also asked what experience was most beneficial to them, whether they made new friends with IBD, and if they would attend the camp again. Thirty-six campers responded (81.8% response rate; median age 14 years [range 10-18]; 83.3% Crohn disease; 41.7% girls). Most reported that the camp improved their confidence (86.1%), acceptance (83.3%), and overall quality of life (75.0%) relating to IBD. Moreover, most reported that meeting their fellow campers was the most beneficial experience to come from the camp (72.2%). Overall, these results emphasize the importance and relevance of such an undertaking.


Subject(s)
Camping/psychology , Colitis, Ulcerative/psychology , Crohn Disease/psychology , Friends/psychology , Psychological Distance , Quality of Life , Self Concept , Adolescent , Child , Colitis, Ulcerative/therapy , Crohn Disease/therapy , Cross-Sectional Studies , Female , Humans , Male , New Zealand , Surveys and Questionnaires
14.
J Gastroenterol Hepatol ; 32(3): 577-582, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27723123

ABSTRACT

Over the last two decades, knowledge on fecal biomarkers has substantially increased. Nowadays, these non-invasive markers of inflammation have significant clinical utility in the management of inflammatory bowel disease. Their use informs the decision to perform endoscopy before diagnosis is made right through to influencing therapeutic choices and the need for interval endoscopic assessment. In this review, the roles of two S100 proteins, calprotectin, and S100A12 are described along with that of lactoferrin, in the context of inflammatory bowel disease.


Subject(s)
Feces/chemistry , Inflammatory Bowel Diseases/diagnosis , Leukocyte L1 Antigen Complex/analysis , S100 Proteins/analysis , S100A12 Protein/analysis , Biomarkers/analysis , Humans
15.
Curr Gastroenterol Rep ; 19(4): 16, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28374309

ABSTRACT

PURPOSE OF REVIEW: Biliary atresia is the most common indication for liver transplantation among children. In recent years, prospective, multi-centre collaboration has been underway with the aim of providing high-quality data on the natural history of the condition, prior to and following hepatic portoenterostomy. RECENT FINDINGS: There is increasing evidence that specific histological findings, and age, at the time of portoenterostomy have relevance as prognostic indicators. Recent data suggest that the sub-type of biliary atresia, its co-existence with other anomalies and concurrent infection may also be important variables. This review provides a comprehensive summary of the histological predictors of outcome following portoenterostomy. Later age at portoenterostomy, advanced degree of hepatic fibrosis and co-existence with other congenital anomalies are strongly correlated with poor outcomes following portoenterostomy. There is increasing evidence to suggest that common serological indices and the presence or absence of cytomegalovirus (CMV) co-infection may have utility as early prognostic indicators.


Subject(s)
Biliary Atresia/surgery , Portoenterostomy, Hepatic , Age Factors , Biliary Atresia/complications , Biliary Atresia/diagnosis , Biliary Atresia/pathology , Biomarkers/blood , Cytomegalovirus Infections/complications , Humans , Infant , Prognosis , Risk Factors , Treatment Outcome
16.
Mediators Inflamm ; 2017: 1936315, 2017.
Article in English | MEDLINE | ID: mdl-28522897

ABSTRACT

There is increasing importance placed upon noninvasive assessment of gut inflammation. These tools are likely to be the key in differentiating intestinal inflammatory disease from functional disorders and in monitoring the response to intervention in individuals with known inflammatory conditions. Although various noninvasive markers are currently available, they have limitations and do not provide ideal utility. This review focuses on emerging markers of gut inflammation, highlighting the potential of specific markers.


Subject(s)
Biomarkers/metabolism , Inflammatory Bowel Diseases/metabolism , Animals , Humans , Inflammation/metabolism
18.
Angew Chem Int Ed Engl ; 55(10): 3352-5, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26834003

ABSTRACT

Carbon-based materials, such as acenes, fullerenes, and graphene nanoribbons, are viewed as the potential successors to silicon in the next generation of electronics. Although a number of methodologies provide access to these materials' all-carbon variants, relatively fewer strategies readily furnish their nitrogen-doped analogues. Herein, we report the rational design, preparation, and characterization of nitrogen-containing rubicenes and tetrabenzopentacenes, which can be viewed either as acene derivatives or as molecular fragments of fullerenes and graphene nanoribbons. The reported findings may prove valuable for the development of electron transporting organic semiconductors and for the eventual construction of larger carbonaceous systems.

19.
Angew Chem Int Ed Engl ; 55(46): 14267-14271, 2016 11 07.
Article in English | MEDLINE | ID: mdl-27714900

ABSTRACT

Advanced molecular electronic components remain vital for the next generation of miniaturized integrated circuits. Thus, much research effort has been devoted to the discovery of lossless molecular wires, for which the charge transport rate or conductivity is not attenuated with length in the tunneling regime. Herein, we report the synthesis and electrochemical interrogation of DNA-like molecular wires. We determine that the rate of electron transfer through these constructs is independent of their length and propose a plausible mechanism to explain our findings. The reported approach holds relevance for the development of high-performance molecular electronic components and the fundamental study of charge transport phenomena in organic semiconductors.

20.
Brain Behav Immun ; 44: 167-175, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25305591

ABSTRACT

Vasoactive intestinal peptide (VIP) and pituitary adenylyl cyclase-activating polypeptide (PACAP) are two structurally-related neuropeptides with widespread expression in the central and peripheral nervous systems. Although these peptides have been repeatedly shown to exert potent anti-inflammatory actions when administered in animal models of inflammatory disease, mice deficient in VIP and PACAP were recently shown to exhibit different phenotypes (ameliorated and exacerbated, respectively) in response to experimental autoimmune encephalomyelitis (EAE). Therefore, elucidating what are the specific immunoregulatory roles played by each of their receptor subtypes (VPAC1, VPAC2, and PAC1) is critical. In this study, we found that mice with a genetic deletion of VIPR2, encoding the VPAC2 receptor, exhibited exacerbated (MOG35-55)-induced EAE compared to wild type mice, characterized by enhanced clinical and histopathological features, increased proinflammatory cytokines (TNF-α, IL-6, IFN-γ (Th1), and IL-17 (Th17)) and reduced anti-inflammatory cytokines (IL-10, TGFß, and IL-4 (Th2)) in the CNS and lymph nodes. Moreover, the abundance and proliferative index of lymph node, thymus and CNS CD4(+)CD25(+)FoxP3(+) Tregs were strikingly reduced in VPAC2-deficient mice with EAE. Finally, the in vitro suppressive activity of lymph node and splenic Tregs from VPAC2-deficient mice was impaired. Overall, our results demonstrate critical protective roles for PACAP and the VPAC2 receptor against autoimmunity, promoting the expansion and maintenance of the Treg pool.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental/immunology , Receptors, Vasoactive Intestinal Peptide, Type II/genetics , Receptors, Vasoactive Intestinal Peptide, Type II/immunology , Animals , Cell Proliferation , Encephalomyelitis, Autoimmune, Experimental/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , Gene Expression , Interferon-gamma/metabolism , Interleukin-17/metabolism , Interleukin-4/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/metabolism , Spinal Cord/pathology , T-Lymphocytes, Regulatory/metabolism , T-Lymphocytes, Regulatory/physiology
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