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Incarcerated gravid uterus (IGU) is a rare and serious obstetric complication. IGU is defined as the entrapment of the gravid uterus between the pubic symphysis and the sacral promontory. The incidence of IGU is 1 in 3000-10 000 cases. IGU is associated with significant obstetric complications, including preterm labor, intrauterine fetal death, growth restriction, renal failure, uterine ischemia/rupture and thrombosis. Here, we present the case of a primigravida with urinary retention at 14 weeks. On transabdominal ultrasound at 19+5/7 weeks the cervix was difficult to visualize, and the anterior uterine wall appeared thickened. The bladder was elongated superior to the uterus and the placenta was low-lying. Initially the patient was managed with intermittent self-catheterization, and subsequently indwelling catheterization was required from 22 weeks. At 30 weeks, the patient was transferred to a tertiary center and magnetic resonance imaging (MRI) was preformed due to challenging visualization of the cervix on ultrasound and the patient's continued symptoms of constipation and recurrent urinary infections. The MRI found a retroflexed gravid uterus, with vagina and endocervix displaced anteriorly and compressed by the gravid uterus. The findings were consistent with an incarcerated uterus. The patient subsequently had positive urinary cultures for Pseudomonas and rising creatinine. Given the obstructive uropathy and associated morbidity and mortality, a plan for elective pre-term delivery at 33+6/7 weeks was made. Delivery was by midline laparotomy, normal anatomy was restored after manual evacuation of the fundus from below the sacral promontory, and an uncomplicated lower segment transverse uterine cesarean section was performed.
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We present the case of a 71-year-old female treated for infective endocarditis with flucloxacillin and paracetamol. Her clinical course became complicated by a blood-gas demonstrating a raised anion gap metabolic acidosis. The patient was diagnosed with pyroglutamic metabolic acidosis. This is a rare interaction between high dose flucloxacillin and paracetamol, and is an important complication to recognize.
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Objective Twin to twin transfusion syndrome (TTTS) complicates 5-15% of monochorionic twin pregnancies and untreated is associated with a 90% mortality rate. The aim was to present the perinatal survival of patients with TTTS treated with laser ablation, by a national fetal medicine team. Methods This was a review of all cases of TTTS treated with fetoscopic laser ablation performed from March 2006 through to December 2020. All patients treated with fetoscopic laser were identified from the hospital database. The perinatal outcomes for the overall cohort and the individual Quintero stages were determined. Results A total of 155 cases of TTTS underwent fetoscopic laser ablation during the study period. The median gestational age at diagnosis was 19+1 weeks, with a mean growth discordance of 23.6%. The Quintero stage at diagnosis was: Stage 1 6.5% (10/155), Stage 2 49% (76/155), Stage 3 38.7% (60/155), Stage 4 5.8% (9/155). There was at least one survivor in 83.2% (129/155) of pregnancies, with dual survival in 52.9% (82/155). An increase in the rate of any survivor was observed from 75% (2006-2014) to 94% (2014-2020) (p<0.05). Dual survival decreased with increasing Quintero Stage (p<0.05). 80.6% (125/155) of pregnancies delivered prior to 34+6 weeks gestation. Conclusion Fetoscopic laser ablation is the recommended first line treatment for severe TTTS. We observed a survival rate of at least one twin in 83.2% pregnancies which is comparable to internationally published data on single-centre outcomes.
Subject(s)
Fetofetal Transfusion , Fetoscopy , Laser Therapy , Female , Fetofetal Transfusion/surgery , Fetoscopy/methods , Gestational Age , Humans , Pregnancy , Pregnancy, TwinABSTRACT
BACKGROUND: Linezolid is an antibiotic used to treat infections caused by multi-drug-resistant Gram-positive bacteria. Linezolid resistance in enterococci has been reported with increasing frequency, with a recent rise in resistance encoded by optrA, poxtA or cfr. AIM: To investigate a hospital outbreak of linezolid- and vancomycin-resistant Enterococcus faecium (LVREfm) using whole-genome sequencing (WGS). METHODS: Thirty-nine VREfm from patient screening (19 isolates, 17 patients) and environmental sites (20 isolates) recovered in October 2019 were investigated. Isolates were screened using polymerase chain reaction for optrA, poxtA and cfr, and underwent Illumina MiSeq WGS. Isolate relatedness was assessed using E. faecium core genome multi-locus sequence typing (cgMLST). One LVREfm underwent MinION long-read WGS (Oxford Nanopore Technologies) and hybrid assembly with MiSeq short-read sequences to resolve an optrA-encoding plasmid. FINDINGS: Twenty isolates (51.3%) were LVREfm and optrA-positive, including the LVREfm from the index patient. A closely related cluster of 28 sequence type (ST) 80 isolates was identified by cgMLST, including all 20 LVREfm and eight linezolid-susceptible VREfm, with an average allelic difference of two (range 0-10), indicating an outbreak. Nineteen (95%) LVREfm harboured a 56,684-bp conjugative plasmid (pEfmO_03). The remaining LVREfm exhibited 44.1% sequence coverage to pEfmO_03. The presence of pEfmO_03 in LVREfm and the close relatedness of the outbreak cluster isolates indicated the spread of a single strain. The outbreak was terminated by enhanced infection prevention and control (IPC) and environmental cleaning measures, ceasing ward admissions and ward-dedicated staff. CONCLUSION: WGS was central in investigating an outbreak of ST80 LVREfm. The rapid implementation of enhanced IPC measures terminated the outbreak.
Subject(s)
Disease Outbreaks , Drug Resistance, Multiple, Bacterial , Enterococcus faecium/drug effects , Gram-Positive Bacterial Infections/epidemiology , Linezolid/pharmacology , Vancomycin/pharmacology , Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Enterococcus faecium/genetics , Genes, Bacterial , Genotype , Gram-Positive Bacterial Infections/microbiology , Hospitals , Humans , Ireland/epidemiology , Microbial Sensitivity Tests , Phenotype , Plasmids/genetics , RNA, Ribosomal, 23S/genetics , Whole Genome SequencingABSTRACT
OBJECTIVE: The objective of this study was to examine the cross-sectional relationship between the expression of norepinephrine transporter (NET), the protein responsible for neuronal uptake-1, and indices of glycaemia and hyperinsulinaemia, in overweight and obese individuals. METHODS: Thirteen non-medicated, non-smoking subjects, aged 58 ± 1 years (mean ± standard error of the mean), body mass index (BMI) 31.4 ± 1.0 kg m-2, with wide-ranging plasma glucose and haemoglobin A1c (HbA1c, range 5.1% to 6.5%) participated. They underwent forearm vein biopsy to access sympathetic nerves for the quantification of NET by Western blot, oral glucose tolerance test (OGTT), euglycaemic hyperinsulinaemic clamp, echocardiography and assessments of whole-body norepinephrine kinetics and muscle sympathetic nerve activity. RESULTS: Norepinephrine transporter expression was inversely associated with fasting plasma glucose (r = -0.62, P = 0.02), glucose area under the curve during OGTT (AUC0-120, r = -0.65, P = 0.02) and HbA1c (r = -0.67, P = 0.01), and positively associated with steady-state glucose utilization during euglycaemic clamp (r = 0.58, P = 0.04). Moreover, NET expression was inversely related to left ventricular posterior wall dimensions (r = -0.64, P = 0.02) and heart rate (r = -0.55, P = 0.05). Indices of hyperinsulinaemia were not associated with NET expression. In stepwise linear regression analysis adjusted for age, body mass index and blood pressure, HbA1c was an independent inverse predictor of NET expression, explaining 45% of its variance. CONCLUSIONS: Hyperglycaemia is associated with reduced peripheral NET expression. Further studies are required to identify the direction of causality.
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Group B streptococcus (GBS) is a leading cause of invasive disease in infants. Accurate and rapid diagnosis is crucial to reduce morbidity and mortality. Real-time polymerase chain reaction (PCR) targeting the dltR gene was utilised for the direct detection of GBS DNA in blood and cerebrospinal fluid (CSF) from infants at an Irish maternity hospital. A retrospective review of laboratory and patient records during the period 2011-2013 was performed in order to evaluate PCR and culture for the diagnosis of invasive GBS disease. A total of 3570 blood and 189 CSF samples from 3510 infants had corresponding culture and PCR results. Culture and PCR exhibited concordance in 3526 GBS-negative samples and 13 (25%) GBS-positive samples (n = 53). Six (11%) and 34 (64%) GBS-positive samples were positive only in culture or PCR, respectively. Culture and PCR identified more GBS-positive infants (n = 47) than PCR (n = 43) or culture (n = 16) alone. Using culture as the reference standard, the sensitivity, specificity, and positive and negative predictive values for PCR on blood samples were 71.4%, 99.2%, 25% and 99.9%, and for CSF samples, they were 60%, 97.8%, 42.9% and 98.9%, respectively. The sensitivity and positive predictive values were improved (blood: 84.6% and 55%; CSF: 77.8% and 100%, respectively) when maternal risk factors and other laboratory test results were considered. The findings in this study recommend the use of direct GBS real-time PCR for the diagnosis of GBS infection in infants with a clinical suspicion of invasive disease and as a complement to culture, but should be interpreted in the light of other laboratory and clinical findings.
Subject(s)
Bacteriological Techniques/methods , Real-Time Polymerase Chain Reaction/methods , Streptococcal Infections/diagnosis , Streptococcus agalactiae/isolation & purification , Blood/microbiology , Cerebrospinal Fluid/microbiology , Female , Humans , Infant , Infant, Newborn , Male , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity , Streptococcus agalactiae/genetics , Streptococcus agalactiae/growth & developmentABSTRACT
In 2008, planned folic acid fortification for the prevention of Neural Tube Defects (NTD) was postponed. Concurrently, the economic recession may have affected dietary folic acid intake, placing increased emphasis on supplement use. This study examined folic acid supplement use in 2009. A cross-sectional survey of 300 ante-natal women was undertaken to assess folic acid knowledge and use. Associations between demographic, obstetric variables and folic acid knowledge and use were examined. A majority, 284/297 (96%), had heard of folic acid, and 178/297 (60%) knew that it could prevent NTD. Most, 270/297 (91%) had taken it during their pregnancy, but only 107/297 (36%) had used it periconceptionally. Being older, married, planned pregnancy and better socioeconomic status were associated with periconceptional use. Periconceptional folic acid use in 2009 was very low, little changed from economic status were associated with periconceptional use. Periconceptional folic acid use in 2009 was very low, little changed from earlier years. Continuous promotion efforts are necessary. Close monitoring of folic acid intake and NTD rates is essential, particularly in the absence of fortification.
Subject(s)
Dietary Supplements , Folic Acid/administration & dosage , Neural Tube Defects/prevention & control , Vitamin B Complex/administration & dosage , Adult , Cross-Sectional Studies , Female , Health Knowledge, Attitudes, Practice , Humans , Pregnancy , Socioeconomic FactorsABSTRACT
Vasovagal syncope (VVS) is the commonest cause of recurrent syncope and has a high level of morbidity in both young and elderly patients. Diagnosis and treatment are often unsatisfactory despite the fact that syncope has a lifetime cumulative incidence of 35%. A detailed history can often yield an accurate diagnosis in most young patients. Older patients are more likely to present in an atypical manner and although the yield is low, a more comprehensive diagnostic assessment may be needed. It is important to identify patients with low supine systolic blood pressure who are prone to recurrent VVS. These patients represent a distinct subtype of VVS and may respond to a tailored therapeutic approach. Treatment options for VVS are limited because of a paucity of randomized trials. The backbone of therapy is educating the patient, avoiding precipitating factors, maintaining hydration and the application of physical counter-pressure manoeuvres. Drug therapy is rarely warranted; however, fludrocortisone, alpha-agonists, such as midodrine and dihydroergotamine, and selective serotonin reuptake inhibitors may be helpful in some patients. Permanent cardiac pacing is rarely needed and randomized trials do not support its use.
Subject(s)
Syncope, Vasovagal/diagnosis , Syncope, Vasovagal/therapy , Animals , Disease Management , Fludrocortisone/therapeutic use , Humans , Patient Education as Topic/methods , Secondary Prevention , Selective Serotonin Reuptake Inhibitors/therapeutic use , Syncope, Vasovagal/physiopathologyABSTRACT
Field trials comparing repellent formulations containing IR3535 (ethyl butylacetylaminopropionate) and deet (N,N-diethyl-3-methylbenzamide) against mosquitoes in Queensland, Australia, were conducted. Two repellents were compared: Avon Bug Guard, containing 7.5% IR3535; and Australian Defense Force (ADF) deet, containing 35% deet in a gel. Two tests were conducted, one in February-March 2006, and the second in February 2007. In the 1st test, the predominant mosquito species collected were Mansonia uniformis (58.9% of collection) and Culex annulirostris (33.4%), and in the 2nd test, the predominant species was Aedes vigilax (85.7% of collection). In the 1st test, Avon Bug Guard provided >95% protection against all mosquitoes for only 1 h, and ADF deet provided the same level of protection for 5 h. In the 2nd field test, Avon Bug Guard provided only 85% protection against all mosquitoes 1 h after repellent application, while ADF deet provided 5 h of protection. The study showed that ADF deet provided significantly better protection against mosquitoes than Avon Bug Guard (IR3535).
Subject(s)
Aedes , Culex , DEET , Insect Repellents , Propionates , Animals , Female , Humans , Male , Mosquito Control , QueenslandABSTRACT
This work presents the first 3-D analysis of lateral dopant diffusion in a patterned structure using a pulsed laser-assisted local electrode atom probe (LEAP). A structure similar to a device channel was created for this work by performing a 3 keV, 1 x 10(15) cm(-2) As+ implant on a poly-Si line patterned wafer with 70 nm line width and 200 nm line pitch. The wafer was subsequently annealed at 950 degrees C for 1s. LEAP samples were made using a site-selective in-situ focused ion beam (FIB) process. The results from LEAP analysis were then compared with high-resolution transmission electron microscopy (HRTEM) and Florida object-oriented process simulator (FLOOPS) results. Good structural agreement was found between the LEAP and HRTEM results. Several 1-D As concentration profiles extracted from the LEAP data were also found to be in good agreement with FLOOPS process simulation results. These profiles also represent for the first time that results from a 3-D process simulator have been able to be confirmed experimentally using a single sample.
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BACKGROUND: Eradication of Helicobacter pylori in gastric mucosa-associated lymphoid tumor can result in lymphoma remission. We prospectively identified/treated infections in nonbulky, advanced stage indolent lymphoma (follicular; nonfollicular lymphoma) eligible for observation. MATERIALS AND METHODS: Stool H. pylori, hepatitis C and Borrelia serologies, Borrelia and Chlamydia fixed tissue PCR, Chlamydia peripheral blood mononuclear cell PCR and hydrogen breath test for small bowel bacterial overgrowth (SBBO) were obtained. RESULTS: Fifty-six patients were enrolled. Positive infections: H. pylori (13); hepatitis C (3); SBBO (11). Negative: Borrelia (13); Chlamydophila psittaci (12, except one PCR). Lymphoma responses to antimicrobial therapy: H. pylori [one complete response (CR), 24+ months; one transient near CR]; hepatitis C [two CRs, 18+ and 30+ months; one partial response (PR) but hepatitis C virus persistent]; SBBO (one PR, 30+ months). Patients with associated infections, but without lymphoma CR, have required lymphoma treatment sooner than those without initial infections (treatment-free survival at 23.4 months median follow-up, 40.5% versus 74.7%, P = 0.01), indicating a different biology. CONCLUSION: Infections are common in advanced stage indolent lymphoma (37.5% in our series). Anecdotal lymphoma responses have been seen and three have been durable CRs (18 to 30+ months) with infection eradication alone. The identification and treatment of associated infections may be a first step towards developing a lymphoma prevention strategy.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Helicobacter Infections/complications , Helicobacter Infections/drug therapy , Lymphoma, B-Cell, Marginal Zone/drug therapy , Lymphoma, B-Cell, Marginal Zone/prevention & control , Stomach Neoplasms/prevention & control , Adult , Aged , Analysis of Variance , Female , Follow-Up Studies , Gastric Mucosa/drug effects , Gastric Mucosa/pathology , Helicobacter Infections/pathology , Helicobacter pylori/drug effects , Helicobacter pylori/isolation & purification , Humans , Immunohistochemistry , Lymphoma, B-Cell, Marginal Zone/microbiology , Lymphoma, B-Cell, Marginal Zone/mortality , Male , Middle Aged , Neoplasm Staging , Prospective Studies , Risk Assessment , Statistics, Nonparametric , Stomach Neoplasms/mortality , Stomach Neoplasms/pathology , Survival Analysis , Treatment OutcomeABSTRACT
BACKGROUND AND PURPOSE: Motilin or 5-HT4 receptor agonists stimulate gastrointestinal motility. Differences in activity are suggested but direct comparisons are few. A method was devised to directly compare the gastric prokinetic activities of motilin, the motilin receptor agonist, erythromycin, and the 5-HT4 receptor agonist, tegaserod. EXPERIMENTAL APPROACH: Gastric prokinetic-like activity was assessed by measuring the ability to facilitate cholinergically-mediated contractions evoked by electrical field stimulation (EFS) in rabbit isolated stomach. Comparisons were made between potency, maximal activity and duration of responses. KEY RESULTS: Rabbit motilin (r.motilin) 0.003-0.3 microM, [Nle13]motilin 0.003-0.3 microM, erythromycin 0.3-10 microM and tegaserod 0.1-10 microM caused concentration - dependent potentiation of EFS-evoked contractions. The potency ranking was r.motilin = [Nle13]motilin > tegaserod > erythromycin. The Emax ranking was r.motilin = [Nle13]motilin = erythromycin > tegaserod. Responses to r.motilin and [Nle13]motilin faded rapidly (t1/2 9 and 11 min, respectively) whereas those to erythromycin and tegaserod were maintained longer (t1/2 24 and 28 min). The difference did not appear to be due to peptide degradation. A second application of [Nle13]motilin was excitatory after 60 min contact and fade of the initial response (responses to 0.03 and 0.1 microM [Nle13]motilin were not different from those caused by the first application). CONCLUSIONS AND IMPLICATIONS: Prokinetic-like activities of the 5-HT4 agonist tegaserod and the motilin receptor agonists were compared by measuring changes in cholinergically-mediated contractions. This novel approach highlighted important differences between classes (greater Emax of motilin, compared with tegaserod) and for the first time, within each class (short t1/2 for motilin, compared with erythromycin).
Subject(s)
Gastrointestinal Agents/pharmacology , Gastrointestinal Motility/drug effects , Indoles/pharmacology , Receptors, Gastrointestinal Hormone/agonists , Receptors, Neuropeptide/agonists , Animals , Carbachol/pharmacology , Dose-Response Relationship, Drug , Electric Stimulation , Erythromycin/pharmacology , Half-Life , In Vitro Techniques , Ligands , Male , Manometry , Motilin/pharmacology , Muscarinic Agonists/pharmacology , Rabbits , Receptors, Serotonin, 5-HT4/drug effects , Serotonin Receptor Agonists/pharmacology , Stimulation, ChemicalABSTRACT
BACKGROUND: Streptococcal throat infections and HLA Cw6 (Cw*06) have been implicated in the pathogenesis of psoriasis, particularly in the guttate form. OBJECTIVES: To study 105 Irish patients with psoriasis to investigate the relationship between streptococcal infections and Cw*06. METHODS: The patients were divided into two groups: those with guttate psoriasis or guttate flare (guttate group, GG, n=64) and those with chronic plaque psoriasis (chronic plaque group, CPG, n=41). RESULTS: The incidence of Cw*06 was 86% in the GG and 73% in the CPG, which was not significantly different (P=0.1725) but the incidence in both groups was significantly higher than in an Irish control group (18%) (P<0.0001 vs. GG and P<0.0001 vs. CPG). Evidence for streptococcal infection was higher in the GG (56%) than in the CPG (32%) (P=0.0231). Of those patients with evidence of streptococcal infection, 30 of 36 GG (83%) and nine of 13 CPG (69%) patients possessed the Cw*06 genotype. CONCLUSIONS: Thus, not all patients with streptococcal-related psoriasis carry Cw*06. The role of Cw*06 in psoriasis, if any, has yet to be determined.
Subject(s)
HLA-C Antigens/genetics , Psoriasis/genetics , Psoriasis/microbiology , Streptococcal Infections/complications , Adolescent , Adult , Child , Child, Preschool , Chronic Disease , Female , Genetic Predisposition to Disease , Humans , Male , Pharyngitis/complications , Pharyngitis/microbiology , Polymerase Chain Reaction/methods , RecurrenceABSTRACT
Neuronal plasticity plays an important role in physiological and pathological processes within the gastrointestinal (GI) tract. Nogo A is a major contributor to the negative effect central nervous system (CNS) myelin has on neurite outgrowth after injury and may also play a role in maintaining synaptic connections in the healthy CNS. Nogo A is highly expressed during neuronal development but in the CNS declines postnatally concomitantly with a loss of regenerative potential while ganglia of the Peripheral Nervous System (PNS) retain Nogo A. The enteric nervous system shares a number of features in common with the CNS, thus the peripheral distribution of factors affecting plasticity is of interest. We have investigated the distribution of Nogo in the adult mammalian gastrointestinal tract. Nogo A mRNA and protein are detectable in the adult rat GI tract. Nogo A is expressed heterogeneously in enteric neurons throughout the GI tract though expression levels appear not to be correlated with neuronal sub-type. The pattern of expression is maintained in cultured myenteric plexus from the guinea-pig small intestine. As is seen in developing neurons of the CNS, enteric Nogo A is present in both neuronal cell bodies and axons. Our results point to a hitherto unsuspected role for Nogo A in enteric neuronal physiology.
Subject(s)
Enteric Nervous System/metabolism , Myelin Proteins/biosynthesis , Animals , COS Cells , Chlorocebus aethiops , Female , Gene Expression Regulation/physiology , Guinea Pigs , Humans , Male , Mice , Myelin Proteins/genetics , Nogo Proteins , RatsABSTRACT
The peptide hormone ghrelin is known to be present within stomach and, to a lesser extent, elsewhere in gut. Although reports suggest that gastric function may be modulated by ghrelin acting via the vagus nerve, the gastrointestinal distribution and functions of its receptor, the growth hormone secretagogue receptor (GHS-R), are not clear and may show signs of species-dependency. This study sought to determine the cellular localisation and distribution of GHS-R-immunoreactivity (-Ir) using immunofluorescent histochemistry and explore the function of ghrelin in both human and rat isolated gastric and/or colonic circular muscle preparations in which nerve-mediated responses were evoked by electrical field stimulation. The expression of GHS-R-Ir differed to a greater extent between species than between gut regions of the same species. Both the human and rat gastric and colonic preparations (n=3 each) expressed GHS-R-Ir within neuronal cell bodies and fibres, cells associated with gastric glands and putative entero-endocrine and/or mast cells. Smooth muscle cells and epithelia were devoid of GHS-R-Ir and only rat preparations expressed GHS-R-Ir on nerve fibres associated with the muscle layers. GHS-R-Ir was fully competed in all cases in pre-adsorption studies and antiserum specificity was confirmed using a cell line transiently expressing the rat GHS-R. In rat isolated forestomach circular muscle, ghrelin 0.1-10 microM had no effect on smooth muscle tension but concentration-dependently facilitated the amplitude of contractions evoked by excitatory nerve stimulation (n=4-7; P<0.05 for each concentration versus vehicle; n=18). When examined under similar conditions, in both rat distal colon (n=4-6, P>0.05 each) and human ascending (n=3) and sigmoid (n=1) colon, these concentrations of ghrelin were without effect (P>0.05 each). The data suggest that ghrelin has the potential to profoundly affect gastrointestinal functions in both species and at least one of these functions is to exert a gastric prokinetic activity. Moreover, we suggest that this activity of ghrelin is mediated via the enteric nervous system, in addition to known vagus nerve-dependent mechanisms.
Subject(s)
Colon/drug effects , Peptide Hormones/pharmacology , Receptors, Cell Surface/metabolism , Receptors, G-Protein-Coupled , Stomach/drug effects , Animals , Atropine/pharmacology , CHO Cells , Colon/cytology , Colon/metabolism , Cricetinae , Dose-Response Relationship, Drug , Evoked Potentials/drug effects , Evoked Potentials/physiology , Female , Gastric Mucosa/metabolism , Ghrelin , Green Fluorescent Proteins , Humans , Immunohistochemistry/methods , Luminescent Proteins/metabolism , Muscarinic Antagonists/pharmacology , Muscle Contraction/drug effects , Muscle Contraction/physiology , Nerve Fibers/metabolism , Peptides/immunology , Peptides/metabolism , Rabbits , Rats , Receptors, Cell Surface/immunology , Receptors, Ghrelin , Stomach/cytology , Transfection/methodsABSTRACT
BACKGROUND: Toll-like receptors (TLRs) are part of the innate immune system involved in the response to microbial pathogens. TLR2 recognizes various ligands expressed by Gram-positive bacteria, while TLR3, TLR4 and TLR5 are specific for double-stranded RNA, Gram-negative lipopolysaccharides and bacterial flagellin, respectively. OBJECTIVES: To determine, firstly, whether epidermal keratinocytes of normal skin express TLRs and, secondly, whether modulation of TLR expression occurs in psoriasis, an inflammatory skin disease associated with certain microorganisms such as streptococci, staphylococci and yeasts. METHODS: Eight samples of normal, and 15 samples of lesional and nonlesional psoriatic skin were stained with polyclonal antibodies specific for TLR1-5 using an avidin-biotin-peroxidase technique. RESULTS: Epidermal keratinocytes in normal skin constitutively expressed TLR1, TLR2 and TLR5, while TLR3 and TLR4 were, in most cases, barely detectable. Cytoplasmic TLR1 and TLR2 were expressed throughout the epidermis, with higher staining of the latter on basal keratinocytes, while TLR5 expression was concentrated in the basal layer. In contrast, in lesional epidermis from patients with psoriasis, TLR2 was more highly expressed on the keratinocytes of the upper epidermis than on the basal layer, while TLR5 was downregulated in basal keratinocytes compared with corresponding nonlesional psoriatic epidermis. In addition, nuclear TLR1 staining was observed in the upper layers of both nonlesional and lesional psoriatic epidermis, but not in that of normal skin. CONCLUSIONS: These findings suggest that TLRs expressed by epidermal keratinocytes constitute part of the innate immune system of the skin. The relevance of altered keratinocyte TLR expression in psoriasis remains to be determined.
Subject(s)
Keratinocytes/metabolism , Membrane Glycoproteins/metabolism , Psoriasis/metabolism , Receptors, Cell Surface/metabolism , Chronic Disease , Female , Humans , Immunoenzyme Techniques , Keratinocytes/immunology , Male , Psoriasis/immunology , Toll-Like Receptor 1 , Toll-Like Receptor 2 , Toll-Like Receptor 3 , Toll-Like Receptor 4 , Toll-Like Receptor 5 , Toll-Like ReceptorsABSTRACT
BACKGROUND: Glycogen synthase kinase-3 (GSK-3) is a serine/threonine protein kinase, the activity of which is inhibited by a variety of extracellular stimuli including insulin, growth factors, cell specification factors and cell adhesion. Consequently, inhibition of GSK-3 activity has been proposed to play a role in the regulation of numerous signalling pathways that elicit pleiotropic cellular responses. This report describes the identification and characterisation of potent and selective small molecule inhibitors of GSK-3. RESULTS: SB-216763 and SB-415286 are structurally distinct maleimides that inhibit GSK-3alpha in vitro, with K(i)s of 9 nM and 31 nM respectively, in an ATP competitive manner. These compounds inhibited GSK-3beta with similar potency. However, neither compound significantly inhibited any member of a panel of 24 other protein kinases. Furthermore, treatment of cells with either compound stimulated responses characteristic of extracellular stimuli that are known to inhibit GSK-3 activity. Thus, SB-216763 and SB-415286 stimulated glycogen synthesis in human liver cells and induced expression of a beta-catenin-LEF/TCF regulated reporter gene in HEK293 cells. In both cases, compound treatment was demonstrated to inhibit cellular GSK-3 activity as assessed by activation of glycogen synthase, which is a direct target of this kinase. CONCLUSIONS: SB-216763 and SB-415286 are novel, potent and selective cell permeable inhibitors of GSK-3. Therefore, these compounds represent valuable pharmacological tools with which the role of GSK-3 in cellular signalling can be further elucidated. Furthermore, development of similar compounds may be of use therapeutically in disease states associated with elevated GSK-3 activity such as non-insulin dependent diabetes mellitus and neurodegenerative disease.