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1.
ACS Chem Biol ; 18(5): 1136-1147, 2023 05 19.
Article in English | MEDLINE | ID: mdl-37094176

ABSTRACT

RNA-targeting small-molecule therapeutics is an emerging field hindered by an incomplete understanding of the basic principles governing RNA-ligand interactions. One way to advance our knowledge in this area is to study model systems where these interactions are better understood, such as riboswitches. Riboswitches bind a wide array of small molecules with high affinity and selectivity, providing a wealth of information on how RNA recognizes ligands through diverse structures. The cobalamin-sensing riboswitch is a particularly useful model system, as similar sequences show highly specialized binding preferences for different biological forms of cobalamin. This riboswitch is also widely dispersed across bacteria and therefore holds strong potential as an antibiotic target. Many synthetic cobalamin forms have been developed for various purposes including therapeutics, but their interaction with cobalamin riboswitches is yet to be explored. In this study, we characterize the interactions of 11 cobalamin derivatives with three representative cobalamin riboswitches using in vitro binding experiments (both chemical footprinting and a fluorescence-based assay) and a cell-based reporter assay. The derivatives show productive interactions with two of the three riboswitches, demonstrating simultaneous plasticity and selectivity within these RNAs. The observed plasticity is partially achieved through a novel structural rearrangement within the ligand binding pocket, providing insight into how similar RNA structures can be targeted. As the derivatives also show in vivo functionality, they serve as several potential lead compounds for further drug development.


Subject(s)
Biochemical Phenomena , Riboswitch , Vitamin B 12/metabolism , Ligands , RNA , Nucleic Acid Conformation
2.
Int J Pharm ; 514(2): 420-427, 2016 Dec 05.
Article in English | MEDLINE | ID: mdl-27210737

ABSTRACT

Pharmacopoeial methods for measurement of the aerodynamic particle size distribution (APSD) of metered dose inhalers (MDIs) by cascade impaction specify a sampling flow rate of 28.3L/min. However, there is little data within the literature to rationalize this figure, or to support its clinical relevance. In addition, the standard United States Pharmacopoeia Induction Port (USP IP) used for testing is known to inaccurately reflect deposition behavior in the upper airway, further compromising the relevance of testing, for product development. This article describes experimental studies of the effect of sampling flow rate on APSD data gathered using an Andersen Cascade Impactor (ACI). Tests were carried out using two different formulations to assess the influence of formulation composition. In addition, comparative testing with an Alberta Idealised Throat, in place of the USP IP, to ensure more realistic representation of the upper airway. The results show how measured APSD and fine particle dose, the dose than on the basis of size would be expected to deposit in the lung, vary as a function of test methodology, providing insight as to how the testing can be modified towards greater clinical relevance.


Subject(s)
Equipment Design , Metered Dose Inhalers/standards , Rheology/instrumentation , Administration, Inhalation , Drug Compounding , Humans , Particle Size
3.
Ir Vet J ; 68: 31, 2015.
Article in English | MEDLINE | ID: mdl-26719792

ABSTRACT

BACKGROUND: Bovine coronavirus is a primary cause of neonatal calf diarrhea worldwide, and is also associated with acute diarrhea in adult cattle during the winter season. There are no reports on molecular characterization of bovine coronavirus in Ireland, and little data exists apart from serological studies. FINDINGS: In this study, 11 neonatal (mean age 9 days) calf BCoV strains from the south of Ireland were collected over a one year period and characterized using molecular methods. The spike gene which encodes a protein involved in viral entry, infectivity and immune response shows the most variability amongst the isolates and was subsequently selected for in depth analysis. Phylogenetic analysis of the spike gene revealed that the Irish strains clustered with novel BCoV strains from Europe in a unique clade, possibly indicating lineage partitioning. Direct analysis of alignments identified amino acid changes in the spike protein unique to the Irish clade. CONCLUSION: Thus, monitoring of bovine coronavirus in Ireland is important as the current isolates in circulation in the south of Ireland may be diverging from the available vaccine strain, which may have implications regarding future BCoV vaccine efficacy.

4.
Arch Virol ; 159(7): 1697-705, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24473708

ABSTRACT

Norovirus (NoV) gastroenteritis occurs in all age groups and is the most common cause of gastroenteritis in the community. However, detection methods and rates vary widely, and few data are available to compare these, particularly in Ireland. Detection of noroviruses through antigen and molecular-based strategies was carried out on 135 suspected NoV-positive samples, collected over the course of three NoV outbreaks, from 2002 to 2006, in the southern region of Ireland. A commercially available ELISA and a panel of six primer sets were evaluated to determine their suitability for NoV detection in Irish clinical samples. The key findings of this study were the detection of both GGI and GGII noroviruses by ELISA, but the detection of only GGII noroviruses by RT-PCR. In addition to this, a variation in the levels of detection from 9.4 % to 17.3 % was observed for conventional PCR assays, while a detection rate of 46.3 % was observed for the real-time PCR assay. A proportion (17.8 %) of samples were found to be negative by all detection strategies, suggesting the possibility of reporting false positives for these samples or low-copy positives that do not often repeat. Sequencing information from selected samples also revealed nucleotide polymorphisms, compromising efficient primer binding in the case of one primer pairing. Phylogenetic analysis of the partial polymerase gene identified NoV GII.4 as the dominant genotype, in accordance with previous NoV studies in Ireland. Investigating the NoV diversity of the circulating strains and the dynamics of strain replacement is important to better assess the efficacy of future NoV vaccines and to facilitate the early detection of changes in circulating NoV strains.


Subject(s)
Caliciviridae Infections/virology , Disease Outbreaks , Enzyme-Linked Immunosorbent Assay/methods , Norovirus/genetics , Norovirus/isolation & purification , Reverse Transcriptase Polymerase Chain Reaction/methods , Base Sequence , Caliciviridae Infections/epidemiology , DNA Primers , Genotype , Humans , Ireland/epidemiology , Molecular Sequence Data , Norovirus/classification , Phylogeny , Sequence Alignment , Time Factors
5.
Eur J Pharm Biopharm ; 86(1): 31-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23523547

ABSTRACT

A series of semi-empirical equations were utilised to design two solution based pressurised metered dose inhaler (pMDI) formulations, with equivalent aerosol performance but different physicochemical properties. Both inhaler formulations contained the drug, beclomethasone dipropionate (BDP), a volatile mixture of ethanol co-solvent and propellant (hydrofluoroalkane-HFA). However, one formulation was designed such that the emitted aerosol particles contained BDP and glycerol, a common inhalation particle modifying excipient, in a 1:1 mass ratio. By modifying the formulation parameters, including actuator orifice, HFA and metering volumes, it was possible to produce two formulations (glycerol-free and glycerol-containing) which had identical mass median aerodynamic diameters (2.4µm±0.1 and 2.5µm±0.2), fine particle dose (⩽5µm; 66µg±6 and 68µg±2) and fine particle fractions (28%±2% and 30%±1%), respectively. These observations demonstrate that it is possible to engineer formulations that generate aerosol particles with very different compositions to have similar emitted dose and in vitro deposition profiles, thus making them equivalent in terms of aerosol performance. Analysis of the physicochemical properties of each formulation identified significant differences in terms of morphology, thermal properties and drug dissolution of emitted particles. The particles produced from both formulations were amorphous; however, the formulation containing glycerol generated particles with a porous structure, while the glycerol-free formulation generated particles with a primarily spherical morphology. Furthermore, the glycerol-containing particles had a significantly lower dissolution rate (7.8%±2.1%, over 180min) compared to the glycerol-free particles (58.0%±2.9%, over 60min) when measured using a Franz diffusion cell. It is hypothesised that the presence of glycerol in the emitted aerosol particles altered solubility and drug transport, which may have implications for BDP pharmacokinetics after deposition in the respiratory tract.


Subject(s)
Beclomethasone/administration & dosage , Beclomethasone/pharmacokinetics , Excipients , Glycerol , Metered Dose Inhalers , Models, Biological , Administration, Inhalation , Aerosols , Chemistry, Pharmaceutical , Drug Design , Excipients/chemistry , Glycerol/chemistry , Microscopy, Electron, Scanning , Models, Chemical , Particle Size , Porosity , Solubility , Surface Properties , Therapeutic Equivalency , Volatilization
6.
Ir Med J ; 106(4): 105-7, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23691842

ABSTRACT

This study aimed to identify the bottlenecks in patients' journeys through an emergency department (ED). For each stage of the patient journey, the average times were compared between two groups divided according to the four hour time frame and disproportionate delays were identified using a significance test These bottlenecks were evaluated with reference to a lean thinking value-stream map and the five focusing steps of the theory of constraints. A total of 434 (72.5%) ED patients were tracked over one week. Logistic regression showed that patients who had radiological tests, blood tests or who were admitted were 4.4, 4.1 and 7.7 times more likely, respectively, to stay over four hours in the ED than those who didn't The stages that were significantly delayed were the time spent waiting for radiology (p = 0.001), waiting for the in-patient team (p = 0.004), waiting for a bed (p < 0.001) and ED doctor turnaround time (p < 0.001).


Subject(s)
Emergency Service, Hospital/standards , Length of Stay/statistics & numerical data , Process Assessment, Health Care , Quality Improvement , Critical Pathways , Emergency Service, Hospital/organization & administration , Female , Hematologic Tests/statistics & numerical data , Hospitalization , Humans , Ireland , Logistic Models , Male , Patient Care Team , Radiography/statistics & numerical data , Time Factors
7.
J Med Virol ; 84(12): 2008-17, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23080510

ABSTRACT

Rotavirus is a major cause of gastroenteritis in young children worldwide. There have been several recent reports concerning rotavirus isolation from adults, particularly in the elderly, presenting with gastroenteritis. In this study, the authors report on rotavirus outbreaks in five separate elderly care facilities between April, and June 2011 in Ireland. The following genotypes were detected; G1P[8] (n = 5/11), G2P[4] (n = 2/11), and G9P[8] (n = 2/11). Thus, similarities to previous reports were found in that G1P[8] predominated, G9P[8] was still detected but G2P[4] was detected for the first time in a geriatric population in Ireland. Here also described is the detection of Group 2 lineage IIC rotavirus in Ireland for the first time.


Subject(s)
Disease Outbreaks , Rotavirus Infections/epidemiology , Rotavirus/genetics , Rotavirus/isolation & purification , Aged , Aged, 80 and over , Antigens, Viral/genetics , Base Sequence , Capsid Proteins/genetics , Female , Genetic Variation , Genotype , Humans , Ireland/epidemiology , Male , Phylogeny , RNA, Viral/genetics , Rotavirus/classification , Rotavirus Infections/virology , Sequence Alignment
8.
J Mech Behav Biomed Mater ; 14: 180-5, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23026696

ABSTRACT

PLGA/pluronic F127 based nerve guidance conduits (NGCs) for peripheral nerve regeneration offer excellent potential for clinical use. To date, little emphasis has been directed towards the effect of pluronic F127 on their subsequent mechanical properties as a function of degradation time or the physiological environment. This report was designed to redress the balance. This study synthesised 5 groups of 20wt% PLGA NGCs with varied additions of pluronic F127 (range 0-5wt%) to obtain Young's Moduli (E) in the range of 7-107MPa, depending on degradation conditions and pluronic F127 content.


Subject(s)
Elastic Modulus , Lactic Acid/chemistry , Lactic Acid/pharmacology , Nerve Regeneration/drug effects , Polyethylenes/chemistry , Polyglycolic Acid/chemistry , Polyglycolic Acid/pharmacology , Polypropylenes/chemistry , Tissue Scaffolds/chemistry , Peripheral Nerves/physiology , Peripheral Nerves/transplantation , Polylactic Acid-Polyglycolic Acid Copolymer , Time Factors
9.
Arch Virol ; 157(9): 1767-73, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22614812

ABSTRACT

Human bocavirus has been increasingly detected worldwide in patients suffering from gastroenteritis, with the highest incidence reported in children aged between 6 and 24 months. A total of 155 non-bacterial gastroenteritis samples consisting of rotavirus-, adenovirus- and norovirus-positive specimens were collected from patients in the Munster region of Ireland from 2006-2008. Of these 155, a total of 12 were positive for the presence of human bocavirus. Three types of human bocavirus were identified: HBoV1, 2 and 3. In addition, recombinant strains (n=4) were also isolated. This is the first report of all three types of HBoV being detected in southern Ireland.


Subject(s)
Gastroenteritis/virology , Human bocavirus/classification , Human bocavirus/isolation & purification , Parvoviridae Infections/virology , Adult , Child, Preschool , Gastroenteritis/epidemiology , Humans , Infant , Ireland/epidemiology , Parvoviridae Infections/epidemiology , Prevalence
10.
Epidemiol Infect ; 140(2): 247-59, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21396145

ABSTRACT

Community and hospital-acquired cases of human rotavirus are responsible for millions of gastroenteritis cases in children worldwide, chiefly in developing countries, and vaccines are now available. During surveillance activity for human rotavirus infections in Ireland, between 2006 and 2009, a total of 420 rotavirus strains were collected and analysed. Upon either PCR genotyping and sequence analysis, a variety of VP7 (G1-G4 and G9) and VP4 (P[4], P[6], P[8] and P[9]) genotypes were detected. Strains G1P[8] were found to be predominant throughout the period 2006-2008, with slight fluctuations seen in the very limited samples available in 2008-2009. Upon either PCR genotyping and sequence analysis of selected strains, the G1, G3 and G9 viruses were found to contain E1 (Wa-like) NSP4 and I1 VP6 genotypes, while the analysed G2 strains possessed E2 NSP4 and I2 VP6 genotypes, a genetic make-up which is highly conserved in the major human rotavirus genogroups Wa- and Kun-like, respectively. Upon sequence analysis of the most common VP4 genotype, P[8], at least two distinct lineages were identified, both unrelated to P[8] Irish rotaviruses circulating in previous years, and more closely related to recent European humans rotaviruses. Moreover, sequence analysis of the VP7 of G1 rotaviruses revealed the onset of a G1 variant, previously unseen in the Irish population.


Subject(s)
Antigens, Viral/genetics , Capsid Proteins/genetics , Gastroenteritis/virology , Rotavirus Infections/virology , Rotavirus/classification , Rotavirus/genetics , Child, Preschool , Electrophoresis, Polyacrylamide Gel , Feces/virology , Genotype , Humans , Ireland , Molecular Sequence Data , Phylogeny , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , Rotavirus/isolation & purification , Sequence Analysis, DNA
11.
Mater Sci Eng C Mater Biol Appl ; 32(6): 1654-63, 2012 Aug 01.
Article in English | MEDLINE | ID: mdl-24364973

ABSTRACT

Poly (lactide-co-glycolide) (PLGA) - Pluronic F127 - glass composites have demonstrated excellent potential, from the perspective of controlled mechanical properties and cytocompatibility, for peripheral nerve regeneration. In addition to controlling the mechanical properties and cytotoxicity for such composite devices, the glass component may mediate specific responses upon implantation via degradation in the physiological environment and release of constituent elements. However, research focused on quantifying the release levels of such therapeutic ions from these experimental medical devices has been limited. To redress the balance, this paper explores the ion release profiles for Si(4+), Ca(2+), Na(+), Zn(2+), and Ce(4+) from experimental composite nerve guidance conduits (CNGC) comprising PLGA (at 12.5, and 20 wt.%), F127 (at 0, 2.5 and 5 wt.%) and various loadings of Si-Ca-Na-Zn-Ce glass (at 20 and 40 wt.%) for incubation periods of up to 28 days. The concentration of each ion, at various time points, was determined using Inductively Coupled Plasma-Atomic Emission Spectrometry (Perkin Elmer Optima 3000). It was observed that the Si(4+), Na(+), Ca(2+), Zn(2+) release from CNGCs in this study ranged from 0.22 to 6.477 ppm, 2.307 to 3.277 ppm, 40 to 119 ppm, and 45 to 51 ppm, respectively. The Ce(4+) concentrations were under the minimum detection limits for the ICP instrument utilized. The results indicate that the ion release levels may be appropriate to mediate therapeutic effects with respect to peripheral nerve regeneration. The data generated in this paper provides requisite evidence to optimize composition for pre-clinical evaluation of the experimental composite.


Subject(s)
Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Ions/chemistry , Nerve Regeneration/drug effects , Peripheral Nerve Injuries/therapy , Glass/chemistry , Lactic Acid/chemistry , Lactic Acid/pharmacology , Materials Testing/methods , Poloxamer/chemistry , Poloxamer/pharmacology , Polyglycolic Acid/chemistry , Polyglycolic Acid/pharmacology , Polylactic Acid-Polyglycolic Acid Copolymer
12.
J Mech Behav Biomed Mater ; 4(7): 1266-74, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21783135

ABSTRACT

The use of nerve guidance conduits to repair peripheral nerve discontinuities has attracted much attention from the biomaterials community, with many resorbable and non-resorbable materials in clinical use. However, a material with ideal biocompatibility, sufficient mechanical properties (to match that of the regenerating nerve) coupled with a suitable degradation rate, has yet to be realized. Recently, potential solutions (composite nerve guidance conduits) which support the emerging philosophy of allowing synthetic materials to establish key interactions with cells in ways that encourage self-repair (i.e. ionic mediators of repair such as those observed in hard tissue regeneration) have been proposed in the literature; such composites comprise specially designed bioactive phosphate-free glasses embedded in degradable polymeric matrices. Whilst much research has focussed on the optimization of such composites, there is no published literature on the performance of these experimental compositions under simulated physiological conditions. To address this key limitation, this paper explores the time-dependent variations in wet-state mechanical properties (tensile modulus and ultimate tensile strength) for NGC composites containing various compositions of PLGA (at 12.5, and 20 wt%), F127 (at 0, 2.5 and 5 wt%) and various loadings of Si-Na-Ca-Zn-Ce glass (at 0 and 20 wt%). It was observed that Young's modulus and ultimate tensile strength of these composites were in the range 5-203 MPa and 1-7 MPa respectively, indicating comparable mechanical performance to clinical materials. Furthermore, an analysis of the cytocompatibility of experimental compositions showed comparable (in some instances superior), compatibility when compared with the commercial product Neurolac(®). Based on current synthetic devices and the demands of the indication, the CNGCs examined in this work offer appropriate mechanical properties and compatibility to warrant enhanced development.


Subject(s)
Coated Materials, Biocompatible/pharmacology , Coated Materials, Biocompatible/toxicity , Guided Tissue Regeneration , Materials Testing/methods , Mechanical Phenomena , Nerve Regeneration/drug effects , Anilides/chemistry , Animals , Cell Line , Cell Survival/drug effects , Coated Materials, Biocompatible/chemistry , Elastic Modulus , Glass/chemistry , Lactic Acid/chemistry , Mice , Phase Transition , Polyglycolic Acid/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer , Temperature , Tensile Strength , Time Factors
13.
Vet Microbiol ; 146(3-4): 238-44, 2010 Dec 15.
Article in English | MEDLINE | ID: mdl-20541335

ABSTRACT

Bovine group A rotavirus is one of the main causes of neonatal diarrhoea in calves. This study examined the different G and P genotypes circulating in the bovine population, from 2002-2009, in the south of Ireland. Rotavirus positive bovine faecal samples (n=332) were collected from the Cork Regional Veterinary Laboratory, between 2002 and 2009 and subjected to RNA extraction, PAGE analysis, and G and P genotyping. Genotyping analysis identified G6, G10, P[5], and P[11] to be the predominant G and P genotypes in the present study, with G6 rotavirus responsible for 70-80% of rotavirus infections. The highest combination of G and P types found was G6 P[5], followed by G6 P[5+11] mixed infection. The prevalence of G6 and G10 has shifted over the years, with an increase in the amount of G10 P[11] being detected. Novel combinations (G6+G10P[11], G6+G10P[5+11] and G10P[5+11]) were also detected for the first time. In addition to this, sequence analysis of the VP7 RT-PCR amplicons has revealed that Irish G6 strains are falling within three different lineages, III-V. During this study, two samples, initially genotyped as G8P[11] were identified through sequence analysis as being true G6, lineage III with a high nucleotide identity to Hun4, a G6 human sample from Hungary. The increase in novel G and P type combinations, as well as changes seen in G6 samples could have an impact on rotavirus vaccination programmes, as the current vaccine available may not offer protection against all of these circulating types.


Subject(s)
Cattle Diseases/virology , Rotavirus Infections/veterinary , Rotavirus/genetics , Animals , Antigens, Viral/genetics , Base Sequence , Capsid Proteins/genetics , Cattle , Cattle Diseases/epidemiology , Electrophoresis, Polyacrylamide Gel , Feces/virology , Genotype , Humans , Ireland/epidemiology , Molecular Sequence Data , Phylogeny , Population Surveillance , Prevalence , Rotavirus/classification , Rotavirus Infections/epidemiology , Rotavirus Infections/virology , Sequence Alignment
14.
Arch Virol ; 155(8): 1247-59, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20526785

ABSTRACT

Porcine group A rotaviruses (GARV) are causative agents of enteritis in piglets and are a large reservoir of genetic material for the diversification of human GARVs. Accumulation of information on the genetic heterogeneity of porcine viruses is pivotal for readily characterising unusual human strains. Screening of 292 fecal samples, collected from 4-5- to 8-9-week-old asymptomatic pigs from four herds in Ireland between 2005 and 2007 resulted in 19 (6.5%) samples testing positive by reverse-transcription PCR (RT-PCR) for GARV. The strains were molecularly characterized to collate data on the VP7 and partial VP4 outer capsid genes. By sequence analysis of the VP7 gene, the Irish strains were identified as G2, G4, G5, G9 and G11 viruses. The G11 strains were closely related to other human and porcine G11 strains, while the G2 strains resembled porcine G2 viruses detected recently in Europe and southern Asia. The G4 strains were distantly related to other G4 human and animal strains, constituting a separate G4 VP7 lineage. Analysis of the G5 strains revealed that they were similar to a selection of G5 human and porcine strains, while the G9 strains resembled other porcine G9 viruses. By sequence analysis of the VP8* fragment of the VP4, the Irish viruses were characterised as P[6], P[7], P[13], P[13]/[22], P[26] and P[32].


Subject(s)
Rotavirus Infections/veterinary , Rotavirus/genetics , Swine Diseases/virology , Animals , Antigens, Viral/genetics , Capsid Proteins/genetics , Feces/virology , Genotype , Ireland , Molecular Sequence Data , Phylogeny , Reverse Transcriptase Polymerase Chain Reaction , Rotavirus/classification , Rotavirus/isolation & purification , Rotavirus Infections/physiopathology , Rotavirus Infections/virology , Sequence Analysis, DNA , Swine/virology , Swine Diseases/physiopathology
15.
Vet Microbiol ; 139(1-2): 176-82, 2009 Oct 20.
Article in English | MEDLINE | ID: mdl-19560886

ABSTRACT

Caliciviruses are an important cause of gastroenteritis in humans and animals. Molecular analysis of the polymerase and capsid genes of porcine caliciviruses, sapoviruses (SaVs) and noroviruses (NoVs), has demonstrated a broad range of genetic diversity but information on their epidemiology and pathogenic role in pigs is limited. In this study, 292 faecal samples were obtained from 4-5 to 8-9 week old asymptomatic pigs from four porcine herds in Ireland during 2005-2007 and were screened by RT-PCR using calicivirus-specific primers. Only seven samples from two porcine herds tested positive for porcine calicivirus. By sequence analysis of the partial RNA-dependent RNA polymerase (RdRp) fragment, six samples from one such herd were closely related to each other (>98% nucleotide identity) and were characterised as genogroup (GG) III (Cowden-like) porcine SaVs. These viruses demonstrated an amino acid (aa) identity of 81.3-98.6% to GGIII SaVs. Conversely, one calicivirus strain, 9/07/Ire (identified from a different herd in 2007), was distantly related to GIII SaVs and displayed 94.6-98.6% aa identity to rare K7-like porcine caliciviruses, representatives of a potential novel SaV genogroup (GGVII), described previously in Japan and the USA. Circulation of SaVs in asymptomatic animals might be a mechanism of virus persistence in porcine populations and should be considered with respect to understanding the epidemiology of these viruses in porcine herds.


Subject(s)
Caliciviridae Infections/veterinary , Sapovirus/genetics , Swine/virology , Animals , Caliciviridae Infections/virology , Carrier State/veterinary , Carrier State/virology , Feces/virology , Ireland , Molecular Sequence Data , Reverse Transcriptase Polymerase Chain Reaction , Sapovirus/physiology , Sequence Analysis, RNA , Swine Diseases/virology
16.
J Clin Microbiol ; 46(10): 3346-54, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18716232

ABSTRACT

Group A rotaviruses are important causative agents of severe, acute dehydrating diarrhea in foals. A total of 86 rotavirus-positive fecal samples, collected from diarrheic foals from 11 counties in three of the four provinces of Ireland, were obtained from the Irish Equine Centre in Kildare during a 7-year (1999 to 2005) passive surveillance study and were characterized molecularly to establish the VP7 (G type) and VP4 (P type) antigenic specificities. Fifty-eight samples (67.5%) were found to contain G3 viruses, while in 26 samples (30.2%) the rotaviruses were typed as G14 and in 2 samples (2.3%) there was a mixed infection, G3 plus G14. All samples except for two, which were untypeable, were characterized as P[12]. Fifty-eight percent of the samples were obtained from County Kildare, the center of the Irish horse industry, where an apparent shift from G3P[12] to G14P[12] was observed in 2003. By sequence analysis of the VP7 protein, the G3 Irish strains were shown to resemble viruses of the G3A subtype (H2-like) (97.1 to 100% amino acid [aa] identity), while the G14 Irish strains displayed 93.9 to 97.1% aa identity to other G14 viruses. In the VP8* fragment of the VP4 protein, the P[12] Irish viruses displayed high conservation (92.3 to 100% aa) with other equine P[12] viruses. Worldwide, G3P[12] and G14P[12] are the most prevalent equine rotavirus strains, and G3P[12] vaccines have been developed for prevention of rotavirus-associated diarrhea in foals. Investigations of the VP7/VP4 diversity of the circulating equine viruses and the dynamics of strain replacement are important for better assessing the efficacies of the vaccines.


Subject(s)
Horse Diseases/virology , Rotavirus Infections/veterinary , Rotavirus/classification , Rotavirus/isolation & purification , Animals , Antigens, Viral/genetics , Antigens, Viral/immunology , Capsid Proteins/genetics , Capsid Proteins/immunology , Feces/virology , Horses , Ireland/epidemiology , Molecular Sequence Data , Phylogeny , RNA, Viral/genetics , Rotavirus/genetics , Rotavirus/immunology , Rotavirus Infections/virology , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Serotyping
17.
J Clin Microbiol ; 46(9): 2973-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18632912

ABSTRACT

Group C rotaviruses are important human enteric pathogens that have also been detected in a variety of mammalian species, including pigs. Group C rotaviruses have been identified in piglets with diarrhea, but their ecology remains to be elucidated. By screening of 292 fecal samples collected from 4- to 5-week-old asymptomatic pigs from four herds in Ireland between 2005 and 2007, 13 (4.4%) samples tested positive by reverse transcription-PCR for group C rotavirus. Group A rotaviruses were also detected in 19 samples but not in conjunction with group C viruses. The gene encoding the major group C neutralization antigen, the outer capsid protein VP7, was sequenced. The majority of the strains were very closely related to each other (>99% amino acid [aa] identity) and were characterized as genogroup G1 since they were genetically related to the prototype porcine strain Cowden (92.6% aa identity). Conversely, two strains (1GA/05/Cork/Ire and 281/07/Dublin/Ire) were characterized as genogroup G6 since they displayed the highest identity (89.2 to 94.0% aa) to porcine G6 strains (43/06-22-like). Unexpectedly, one such G6 strain, 1GA/05/Cork/Ire, lacked the 4-aa insertion in the VP7 variable region VR8 found in all the other G6 group C rotaviruses. This study provides evidence that porcine group C rotavirus may be detected not infrequently in asymptomatic piglets. In addition, it provides evidence that, unlike the human viruses, porcine group C rotaviruses display broad genetic heterogeneity, which may pose a challenge for the development of prophylactic tools.


Subject(s)
Rotavirus Infections/veterinary , Rotavirus , Animals , Feces/virology , Ireland , Molecular Sequence Data , Reverse Transcriptase Polymerase Chain Reaction , Rotavirus/genetics , Rotavirus Infections/virology , Swine/virology , Swine Diseases/virology
18.
J Med Virol ; 80(3): 524-30, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18205218

ABSTRACT

Six hundred and thirty three fecal specimens were collected from patients under 6 years, suffering from non-bacterial, putative viral gastroenteritis in the south of Ireland, between 2003 and 2006. Following laboratory identification of rotavirus as the aetiological agent in 558 specimens, reverse transcriptase polymerase chain reaction was employed to amplify the VP7 and VP4 gene segments of 249 and 245 samples, respectively. G and P typing was subsequently carried out on these amplicons. G1 (65.1%), and G3 (16.1%) were found to be the most prevalent circulating G types over the course of the study. Both G2 (1.2%) and G9 (3.6%), were also found to be circulating, however, these types were less frequently detected. Mixed G type infections were found to account for 41 samples (14%). P typing was carried out on 245 samples. P[8] was the most commonly detected P type over the course of the study (93.5%). Both P[6] and P[9], which had not previously been detected in the Irish population, were detected during this investigation. P[6] was detected in both single and mixed P type infections, while P[9] was detected as part of mixed infections only. The key findings of this study were the emergence of P[6] and P[9] as epidemiologically important rotavirus strains in the Irish population. The profile of rotavirus is changing continuously in Ireland, and continued surveillance of the circulating strains is needed to detect the appearance of new strains, or new variants which could escape immune protection induced by an outdated vaccine.


Subject(s)
Gastroenteritis/virology , Rotavirus Infections/epidemiology , Rotavirus Infections/virology , Rotavirus/genetics , Child, Preschool , Feces/virology , Gastroenteritis/epidemiology , Genome, Viral , Genotype , Humans , Ireland/epidemiology , Molecular Epidemiology , Phylogeny , Reverse Transcriptase Polymerase Chain Reaction , Rotavirus/classification , Rotavirus/isolation & purification
19.
J Med Virol ; 79(10): 1518-26, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17705179

ABSTRACT

Enteric adenoviruses have been shown to be a substantial cause of pediatric gastroenteritis in various parts of the world, and are considered to be the second most common cause of viral gastroenteritis, next to rotavirus in young children. Genetic characterization of 95 adenovirus isolates obtained from patients with acute gastroenteritis between 2002 and 2007 from the southern regions of Ireland, were characterized by PCR analysis, restriction endonuclease (RE) analysis and sequencing analysis. All isolates were found to be of adenovirus type 41 origin. Genetic analysis of seven hypervariable regions (HVRs) located within the hexon gene has revealed a high level of amino acid sequence homology in samples over the course of this study, with a very close relationship to the D22 genome type. The D22 genome type has been detected in several other countries, thus suggesting Irish isolates have common genome types with other stains worldwide. This is the first such study undertaken in the south of Ireland, to type and genetically characterize adenoviral gastroenteritis isolates, and has revealed a high level of conservation within the isolated analyzed.


Subject(s)
Adenoviridae Infections/epidemiology , Adenoviruses, Human/genetics , Gastroenteritis/epidemiology , Molecular Epidemiology , Adenoviruses, Human/classification , Amino Acid Sequence , Capsid Proteins/genetics , Feces/virology , Gastroenteritis/virology , Genome, Viral , Hospitals , Humans , Ireland/epidemiology , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , Restriction Mapping , Rotavirus Infections/epidemiology , Sequence Alignment , Sequence Analysis
20.
Vet Microbiol ; 117(2-4): 242-7, 2006 Oct 31.
Article in English | MEDLINE | ID: mdl-16844325

ABSTRACT

One hundred and two faecal samples were collected from calves diagnosed with rotavirus infection, in the southern region of Ireland, from 2002 to 2004. Ninety one percent (n=93) were confirmed positive for rotavirus, using latex agglutination and enzyme linked immunosorbent assay (ELISA) methods. Determination of the G- and P-types was carried out using nested reverse transcriptase polymerase chain reaction (nRT-PCR). G6 was the most prevalent genotype, accounting for 80.6% (75/93), G10 accounted for 6.5% (6/93) and G6G10 mixed types accounted for 9.7% (9/93) of the collection. Rotavirus in three of the samples (3.2%) could not be characterised with any of the five G-specific primers used in this study. A subset of the positive samples (n=54) was examined for their P-type specificities, P[5] and P[11] accounted for 77.8% (42/54), and 9.3% (5/54), respectively. One P[1] genotype (1.9%) was found in the collection. P[5] and P[11] mixed genotypes accounted for 11% (6/54) of the study. The genotypes corresponded to the UK-like strain (G6P[5]) 57.4%, KN4-like strain (G6[P11]) 7.4%, B223-like strain (G10P[11]) and NCDV-like strain (G6P[1]) 1.9% each. The unusual combination of G10P[5] accounted for 7.4%, with mixed infections G6+G10P[5] and G6P[5]+P[11] representing 13% and 11%, respectively. This is the first time that the G- and P-types of bovine rotaviruses (BRVs) have been determined in Ireland, and this study contributes to a better understanding of the epidemiology of such viruses circulating in Ireland.


Subject(s)
Cattle Diseases/epidemiology , Rotavirus Infections/veterinary , Rotavirus/isolation & purification , Animals , Base Sequence , Cattle , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/veterinary , Feces/microbiology , Genotype , Ireland/epidemiology , Latex Fixation Tests/methods , Latex Fixation Tests/veterinary , Molecular Sequence Data , Phylogeny , RNA, Viral/chemistry , Rotavirus/classification , Rotavirus/genetics , Rotavirus Infections/epidemiology
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