RESUMO
Antibody effector functions including antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADCP) are mediated through the interaction of the antibody Fc region with Fcγ receptors present on immune cells. Several approaches have been used to modulate antibody Fc-Fcγ interactions with the goal of driving an effective antitumor immune response, including Fc point mutations and glycan modifications. However, robust antibody-Fcγ engagement and immune cell binding of Fc-enhanced antibodies in the periphery can lead to the unwanted induction of systemic cytokine release and other dose-limiting infusion-related reactions. Creating a balance between effective engagement of Fcγ receptors that can induce antitumor activity without incurring systemic immune activation is an ongoing challenge in the field of antibody and immuno-oncology therapeutics. Herein, we describe a method for the reversible chemical modulation of antibody-Fcγ interactions using simple poly(ethylene glycol) (PEG) linkers conjugated to antibody interchain disulfides with maleimide attachments. This method enables dosing of a therapeutic with muted Fcγ engagement that is restored in vivo in a time-dependent manner. The technology was applied to an effector function enhanced agonist CD40 antibody, SEA-CD40, and experiments demonstrate significant reductions in Fc-induced immune activation in vitro and in mice and nonhuman primates despite showing retained efficacy and improved pharmacokinetics compared to the parent antibody. We foresee that this simple, modular system can be rapidly applied to antibodies that suffer from systemic immune activation due to peripheral FcγR binding immediately upon infusion.
Assuntos
Receptores de IgG , Animais , Camundongos , Receptores de IgG/imunologia , Humanos , Polietilenoglicóis/química , Citotoxicidade Celular Dependente de Anticorpos , Fagocitose/efeitos dos fármacosRESUMO
Clathrin-dependent transport processes require the polymerization of clathrin triskelia into polygonal scaffolds. Together with adapter proteins, clathrin collects cargo and induces membrane bud formation. It is not known to what extent clathrin light chains affect the structural and functional properties of clathrin lattices and the ability of clathrin to deform membranes. To address these issues, we have developed a novel procedure for analyzing clathrin lattice formation on rigid surfaces. We found that lattices can form on adaptor-coated convex-, planar- and even shallow concave surfaces, but the rate of formation and resistance to thermal dissociation of the lattice are greatly enhanced on convex surfaces. Atomic force microscopy on planar clathrin lattices demonstrates that the stiffness of the clathrin lattice is strictly dependent on light chains. The reduced stiffness of the lattice also compromised the ability of clathrin to generate coated buds on the surface of rigid liposomal membranes.
Assuntos
Cadeias Leves de Clatrina/ultraestrutura , Vesículas Revestidas por Clatrina/ultraestrutura , Modelos Biológicos , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/ultraestrutura , Animais , Sítios de Ligação , Cadeias Leves de Clatrina/metabolismo , Vesículas Revestidas por Clatrina/metabolismo , Lipossomos/ultraestrutura , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Polivinil/química , Propriedades de SuperfícieRESUMO
WNT10A gene encodes a canonical wingless pathway signaling molecule involved in cell fate specification as well as morphogenetic patterning of the developing ectoderm, nervous system, skeleton, and tooth. In patients, WNT10A mutations are responsible for ectodermal-derived pathologies including isolated hypo-oligodontia, tricho-odonto-onycho-dermal dysplasia and Schöpf-Schulz-Passarge syndrome (SSPS). Here we describe the dental, ectodermal, and extra-ectodermal phenotypic features of a cohort of 41 patients from 32 unrelated families. Correlations with WNT10A molecular status (heterozygous carrier, compound heterozygous, homozygous) and patient's phenotypes were performed. Mild to severe oligodontia was observed in all patients bearing biallelic WNT10A mutations. However, patients with compound heterozygous mutations presented no significant difference in phenotypes compared with homozygous individuals. Anomalies in tooth morphology were frequently observed with heterozygous patients displaying hypodontia. No signs of SSPS, especially eyelids cysts, were detected in our cohort. Interestingly, extra-ectodermal signs consisted of skeletal, neurological and vascular anomalies, the latter suggesting a wider phenotypic spectrum associated with WNT10A mutations. Indeed, the Wnt pathway plays a crucial role in skeletal development, lipid metabolism, and neurogenesis, potentially explaining patient's clinical manifestations.
Assuntos
Estudos de Associação Genética , Mutação/genética , Dente/patologia , Proteínas Wnt/genética , Adolescente , Adulto , Criança , Estudos de Coortes , Tomografia Computadorizada de Feixe Cônico , Ectoderma/patologia , Heterozigoto , Homozigoto , Humanos , Mandíbula/patologia , Pessoa de Meia-Idade , Fenótipo , Dente/diagnóstico por imagem , Adulto JovemRESUMO
BACKGROUND: Transthyretin amyloidosis is caused by the deposition of hepatocyte-derived transthyretin amyloid in peripheral nerves and the heart. A therapeutic approach mediated by RNA interference (RNAi) could reduce the production of transthyretin. METHODS: We identified a potent antitransthyretin small interfering RNA, which was encapsulated in two distinct first- and second-generation formulations of lipid nanoparticles, generating ALN-TTR01 and ALN-TTR02, respectively. Each formulation was studied in a single-dose, placebo-controlled phase 1 trial to assess safety and effect on transthyretin levels. We first evaluated ALN-TTR01 (at doses of 0.01 to 1.0 mg per kilogram of body weight) in 32 patients with transthyretin amyloidosis and then evaluated ALN-TTR02 (at doses of 0.01 to 0.5 mg per kilogram) in 17 healthy volunteers. RESULTS: Rapid, dose-dependent, and durable lowering of transthyretin levels was observed in the two trials. At a dose of 1.0 mg per kilogram, ALN-TTR01 suppressed transthyretin, with a mean reduction at day 7 of 38%, as compared with placebo (P=0.01); levels of mutant and nonmutant forms of transthyretin were lowered to a similar extent. For ALN-TTR02, the mean reductions in transthyretin levels at doses of 0.15 to 0.3 mg per kilogram ranged from 82.3 to 86.8%, with reductions of 56.6 to 67.1% at 28 days (P<0.001 for all comparisons). These reductions were shown to be RNAi-mediated. Mild-to-moderate infusion-related reactions occurred in 20.8% and 7.7% of participants receiving ALN-TTR01 and ALN-TTR02, respectively. CONCLUSIONS: ALN-TTR01 and ALN-TTR02 suppressed the production of both mutant and nonmutant forms of transthyretin, establishing proof of concept for RNAi therapy targeting messenger RNA transcribed from a disease-causing gene. (Funded by Alnylam Pharmaceuticals; ClinicalTrials.gov numbers, NCT01148953 and NCT01559077.).
Assuntos
Neuropatias Amiloides Familiares/terapia , Pré-Albumina/genética , RNA Interferente Pequeno/uso terapêutico , Adolescente , Adulto , Neuropatias Amiloides Familiares/genética , Animais , Relação Dose-Resposta a Droga , Feminino , Humanos , Lipossomos , Macaca fascicularis , Masculino , Nanocápsulas , Pré-Albumina/metabolismo , RNA Interferente Pequeno/administração & dosagem , Adulto JovemRESUMO
BACKGROUND: The purpose of this study is to compare liposomal bupivacaine to a modified (Ranawat) local injection for total knee arthroplasty (TKA). METHODS: This is a prospective, randomized study of 105 consecutive patients undergoing primary TKA. Group A patients received a periarticular injection with liposomal bupivacaine and group B with a mixture of ropivacaine, epinephrine, ketorolac, and clonidine. There were 54 patients in the group A (liposomal bupivacaine) and 51 in group B. RESULTS: There were no differences in the groups with respect to age, sex, and preoperative knee scores. There were no differences with respect to postoperative narcotic usage and knee range of motion. CONCLUSION: Liposomal bupivacaine as a periarticular injection after TKA demonstrated similar pain levels, narcotic usage, and range of motion compared to a modified Ranawat suspension but improved walking distance.
Assuntos
Analgésicos/administração & dosagem , Artroplastia do Joelho , Bupivacaína/administração & dosagem , Dor Pós-Operatória/prevenção & controle , Idoso , Amidas/administração & dosagem , Clonidina/administração & dosagem , Epinefrina/administração & dosagem , Feminino , Humanos , Injeções , Cetorolaco/administração & dosagem , Lipossomos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Prospectivos , RopivacainaRESUMO
OBJECTIVE: To report the findings of the enhanced surveillance set up in New South Wales in response to the recent outbreak of human enterovirus 71 (EV71) infection. DESIGN AND SETTING: A two-armed enhanced public health surveillance system including statewide emergency department surveillance and clinical surveillance at the Sydney Children's Hospitals Network. PARTICIPANTS: Children aged less than 10 years with suspected or confirmed enterovirus infection. MAIN OUTCOME MEASURES: Epidemiology of the outbreak, including weekly case counts, demographic information, geographic spread of the outbreak, and clinical presentation and progression. RESULTS: Statewide weekly case counts indicate that an epidemic of EV71 infection occurred in NSW from December 2012 until May 2013. Around 119 children were reported with disease severe enough to warrant admission to a tertiary Sydney children's hospital. Cases were spread throughout the Sydney metropolitan area and there is some evidence of geographic migration of the outbreak. Presenting features included fever, lethargy, myoclonus and skin rash. Only 24% of cases presented with classical hand, foot and mouth disease. CONCLUSIONS: EV71 infection is likely to continue to be a public health problem in Australia. Surveillance of routinely collected emergency department data can provide a useful indication of its activity in the community.
Assuntos
Surtos de Doenças/estatística & dados numéricos , Encefalite Viral/epidemiologia , Enterovirus Humano A , Infecções por Enterovirus/epidemiologia , Criança , Pré-Escolar , Cidades/epidemiologia , Surtos de Doenças/prevenção & controle , Serviço Hospitalar de Emergência/estatística & dados numéricos , Encefalite Viral/prevenção & controle , Encefalite Viral/virologia , Infecções por Enterovirus/prevenção & controle , Infecções por Enterovirus/virologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , New South Wales/epidemiologia , Vigilância da PopulaçãoRESUMO
South Georgia and the South Sandwich Islands (SGSSI) are surrounded by oceans that are species-rich, have high levels of biodiversity, important endemism and which also support large aggregations of charismatic upper trophic level species. Spatial management around these islands is complex, particularly in the context of commercial fisheries that exploit some of these living resources. Furthermore, management is especially complicated as local productivity relies fundamentally upon biological production transported from outside the area. The MPA uses practical management boundaries, allowing access for the current legal fisheries for Patagonian toothfish, mackerel icefish and Antarctic krill. Management measures developed as part of the planning process designated the whole SGSSI Maritime Zone as an IUCN Category VI reserve, within which a number of IUCN Category I reserves were identified. Multiple-use zones and temporal closures were also designated. A key multiple-use principle was to identify whether the ecological impacts of a particular fishery threatened either the pelagic or benthic domain.
Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Ilhas Atlânticas , Oceano Atlântico , BiodiversidadeRESUMO
Pregnant or lactating staff working in the orthopaedic operating room may be at risk of occupational exposure to several hazards, including blood-borne pathogens, anesthetic gases, methylmethacrylate, physical stress, and radiation. Because the use of proper personal protective equipment is mandatory, the risk of contamination with blood-borne pathogens such as hepatitis B, hepatitis C, and HIV is low. Moreover, effective postexposure prophylactic regimens are available for hepatitis B and HIV. In the 1960s, concerns were raised about occupational exposure to harmful chemicals in the operating room such as anesthetic gases and methylmethacrylate. Guidelines on safe levels of exposure to these chemicals and the use of personal protective equipment have helped to minimize the risks to pregnant or lactating staff. Short periods of moderate physical activity are beneficial for pregnant women, but prolonged strenuous activity can lead to increased pregnancy complications. The risk of prenatal radiation exposure during orthopaedic procedures is of concern, as well. However, proper lead protection and contamination control can minimize the risk of occupational exposure to radiation.
Assuntos
Exposição Ocupacional , Salas Cirúrgicas , Ortopedia , Gestantes , Anestésicos Inalatórios/toxicidade , Patógenos Transmitidos pelo Sangue , Feminino , Humanos , Lactação , Metilmetacrilato/toxicidade , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/prevenção & controle , Gravidez , Radiação Ionizante , Estresse FisiológicoRESUMO
The article describes the construction, immobilisation and electrochemistry of histidine tagged laccase from Melanocarpus albomyces. A facile method of functionalisation of glassy carbon electrodes with nitrilotriacetic acid (NTA) using diazonium grafting and solid state chemistry is described. NTA-modified electrodes are shown to bind laccase which reduces oxygen at neutral pH in the presence of soluble redox mediator. Laccase-modified electrodes are also prepared by enzyme immobilisation within poly(aniline)/poly(vinylsulfonate) films. The polymer is found to efficiently retain the enzyme as well as provide direct electrical contact between the electrode and the enzyme active centre. Cyclic voltammetry reveals the direct electron transfer to the enzyme is dependent on the redox state of the polymer film.
Assuntos
Ascomicetos/enzimologia , Técnicas Eletroquímicas , Histidina/metabolismo , Lacase/metabolismo , Ácido Nitrilotriacético/metabolismo , Compostos de Anilina/química , Compostos de Anilina/metabolismo , Carbono/química , Carbono/metabolismo , Compostos de Diazônio/química , Compostos de Diazônio/metabolismo , Condutividade Elétrica , Eletrodos , Histidina/química , Lacase/química , Ácido Nitrilotriacético/química , Oxirredução , Oxigênio/química , Oxigênio/metabolismo , Polivinil/química , Polivinil/metabolismo , Propriedades de SuperfícieRESUMO
Blood (serum/plasma) antiepileptic drug (AED) therapeutic drug monitoring (TDM) has proven to be an invaluable surrogate marker for individualizing and optimizing the drug management of patients with epilepsy. Since 1989, there has been an exponential increase in AEDs with 23 currently licensed for clinical use, and recently, there has been renewed and extensive interest in the use of saliva as an alternative matrix for AED TDM. The advantages of saliva include the fact that for many AEDs it reflects the free (pharmacologically active) concentration in serum; it is readily sampled, can be sampled repetitively, and sampling is noninvasive; does not require the expertise of a phlebotomist; and is preferred by many patients, particularly children and the elderly. For each AED, this review summarizes the key pharmacokinetic characteristics relevant to the practice of TDM, discusses the use of other biological matrices with particular emphasis on saliva and the evidence that saliva concentration reflects those in serum. Also discussed are the indications for salivary AED TDM, the key factors to consider when saliva sampling is to be undertaken, and finally, a practical protocol is described so as to enable AED TDM to be applied optimally and effectively in the clinical setting. Overall, there is compelling evidence that salivary TDM can be usefully applied so as to optimize the treatment of epilepsy with carbamazepine, clobazam, ethosuximide, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, primidone, topiramate, and zonisamide. Salivary TDM of valproic acid is probably not helpful, whereas for clonazepam, eslicarbazepine acetate, felbamate, pregabalin, retigabine, rufinamide, stiripentol, tiagabine, and vigabatrin, the data are sparse or nonexistent.
Assuntos
Anticonvulsivantes/análise , Monitoramento de Medicamentos/métodos , Saliva/química , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/farmacocinética , Epilepsia/tratamento farmacológico , Humanos , Saliva/metabolismoRESUMO
Surface functionalization of hydroxyapatite (HA) and beta-tricalcium phosphate (TCP) bioceramics with chemical ligands containing a pyrrogallol moiety was developed to improve the adhesion of bone cell precursors to the biomaterials. Fast and biocompatible copper-free click reaction with azido-modified human fetal osteoblasts resulted in improved cell binding to both HA and TCP bioceramics, opening the way for using this methodology in the preparation of cell-engineered bone implants.
Assuntos
Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Adesão Celular , Cerâmica/química , Durapatita/química , Feto/metabolismo , Osteoblastos/metabolismo , Materiais Biocompatíveis/metabolismo , Fosfatos de Cálcio/metabolismo , Proliferação de Células , Células Cultivadas , Cerâmica/metabolismo , Química Click , Durapatita/metabolismo , Feto/citologia , Humanos , Teste de Materiais , Estrutura Molecular , Osteoblastos/citologia , Propriedades de SuperfícieRESUMO
The phenotype of hereditary apolipoprotein A-I amyloidosis is heterogeneous with some patients developing extensive visceral amyloid deposits and end-stage renal failure as young adults and others having only laryngeal and/or skin amyloid, which may be of little clinical consequence. Clinical management and prognosis of patients with systemic amyloidosis depend entirely on correct identification of the fibril protein, such that light chain amyloidosis (AL, previously referred to as "primary"), the most frequently diagnosed type, is treated with chemotherapy, which has absolutely no role in hereditary apolipoprotein A-I amyloidosis. We report five novel apolipoprotein A-I variants, four of which were amyloidogenic and one of which was incidental in a patient with systemic AL amyloidosis. Interestingly, only one of four patients with apolipoprotein A-I amyloidosis had a family history of similar disease. Laser microdissection and tandem mass spectrometry-based proteomics were used to confirm the amyloid fibril protein and, for the first time in apolipoprotein A-I amyloidosis, demonstrated that only mutated protein as opposed to wild-type apolipoprotein A-I was deposited as amyloid. The clinical spectrum and outcome of hereditary apolipoprotein A-I amyloidosis are reviewed in detail and support the need for sequencing of the apolipoprotein A-I gene among patients with apparent localized amyloidosis in whom IHC is nondiagnostic of the fibril protein, even in the absence of a family history of disease.
Assuntos
Amiloidose/genética , Amiloidose/patologia , Apolipoproteína A-I/genética , Mutação/genética , Adulto , Idoso , Amiloide/metabolismo , Amiloidose/diagnóstico por imagem , Biópsia , Análise Mutacional de DNA , Feminino , Humanos , Imuno-Histoquímica , Lasers , Masculino , Microdissecção , Pessoa de Meia-Idade , Proteínas Mutantes/metabolismo , Palato/patologia , Fenótipo , Proteômica , Cintilografia , Componente Amiloide P Sérico , Espectrometria de Massas em TandemRESUMO
PURPOSE: Lacosamide is a new antiepileptic drug that has a novel mechanism of action, linear pharmacokinetics, and proven efficacy in the adjunctive treatment of partial-onset seizures. We ascertained the relationship between serum and saliva lacosamide concentrations so as to determine whether saliva may be a useful alternative to serum for therapeutic drug monitoring. METHODS: Blood samples were obtained from 98 people with intractable epilepsy (51 male; mean age 43 ± 12; range 19-76 years) prescribed lacosamide as adjunctive therapy. For 48 patients, concurrent saliva samples were also collected. Lacosamide concentrations in serum (free and total) and in saliva were determined by high performance liquid chromatography (HPLC). RESULTS: Linear regression analysis showed a good correlation between lacosamide dose and both total (r(2) = 0.825; n = 32) and free (r(2) = 0.815; n = 29) serum concentrations, and lacosamide serum total and free concentrations were linearly related (r(2) = 0.721; n = 97). There was also a good correlation between saliva lacosamide and both total (r(2) = 0.842; n = 49) and free (r(2) = 0.828; n = 47) serum lacosamide concentrations. Based on the saliva data, the protein binding of lacosamide in serum is calculated to be 87 ± 4% and is comparable to the value calculated by direct measurement of the free and total lacosamide concentration in serum (91 ± 4%). DISCUSSION: These data support the use of saliva as a viable alternative to serum for monitoring lacosamide therapy in patients with epilepsy.
Assuntos
Acetamidas/metabolismo , Anticonvulsivantes/metabolismo , Epilepsia/metabolismo , Acetamidas/sangue , Adulto , Idoso , Anticonvulsivantes/sangue , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Epilepsia/sangue , Feminino , Humanos , Lacosamida , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Saliva/química , Saliva/metabolismo , Adulto JovemRESUMO
The long-term survival of biomaterial implants is often hampered by surgery-induced inflammation that can lead to graft failure. Considering that most corneas receiving grafts are either pathological or inflamed before implantation, the risk of rejection is heightened. Here, we show that bioengineered, fully synthetic, and robust corneal implants can be manufactured from a collagen analog (collagen-like peptide-polyethylene glycol hybrid, CLP-PEG) and inflammation-suppressing polymeric 2-methacryloyloxyethyl phosphorylcholine (MPC) when stabilized with the triazine-based crosslinker 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. The resulting CLP-PEG-MPC implants led to reduced corneal swelling, haze, and neovascularization in comparison to CLP-PEG only implants when grafted into a mini-pig cornea alkali burn model of inflammation over 12 months. Implants incorporating MPC allowed for faster nerve regeneration and recovery of corneal sensation. CLP-PEG-MPC implants appear to be at a more advanced stage of regeneration than the CLP-PEG only implants, as evidenced by the presence of higher amounts of cornea-specific type V collagen, and a corresponding decrease in the presence of extracellular vesicles and exosomes in the corneal stroma, in keeping with the amounts present in healthy, unoperated corneas.
Assuntos
Álcalis/toxicidade , Queimaduras Químicas/complicações , Colágeno/farmacologia , Córnea/citologia , Hidrogéis/administração & dosagem , Inflamação/prevenção & controle , Fosforilcolina/química , Animais , Materiais Biocompatíveis/química , Queimaduras Químicas/patologia , Colágeno/química , Humanos , Hidrogéis/química , Inflamação/etiologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Suínos , Porco MiniaturaRESUMO
INTRODUCTION: Ecological approaches to dental caries prevention play a key role in attaining long-term control over the disease and maintaining a symbiotic oral microbiome. OBJECTIVES: This study aimed to investigate the microbial ecological effects of 2 interventional dentifrices: a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) dentifrice and the same dentifrice supplemented with a polyphenol-rich cranberry extract. METHODS: The interventional toothpastes were compared with each other and with an active control fluoride dentifrice in a double-blinded randomized controlled trial. Real-time quantitative polymerase chain reaction (qPCR) analysis was used to determine changes in the bacterial loads of 14 key bacterial species (8 caries associated and 6 health associated) in the dental plaque of trial participants after they used the dentifrices for 5 to 6 wk. RESULTS: From the baseline to the recall visit, significant differences were observed between the treatment groups in the bacterial loads of 2 caries-associated bacterial species (Streptococcus mutans [P < 0.001] and Veillonella parvula [P < 0.001]) and 3 health-associated bacterial species (Corynebacterium durum [P = 0.008], Neisseria flavescens [P = 0.005], and Streptococcus sanguinis [P < 0.001]). Compared to the fluoride control dentifrice, the CPP-ACP dentifrice demonstrated significant differences for S. mutans (P = 0.032), C. durum (P = 0.007), and S. sanguinis (P < 0.001), while combination CPP-ACP-cranberry dentifrice showed significant differences for S. mutans (P < 0.001), V. parvula (P < 0.001), N. flavescens (P = 0.003), and S. sanguinis (P < 0.001). However, no significant differences were observed in the bacterial load comparisons between the CPP-ACP and combination dentifrices for any of the targeted bacterial species (P > 0.05). CONCLUSIONS: Overall, the results indicate that dentifrices containing CPP-ACP and polyphenol-rich cranberry extracts can influence a species-level shift in the ecology of the oral microbiome, resulting in a microbial community less associated with dental caries (Australian New Zealand Clinical Trial Registry ANZCTR 12618000095268). KNOWLEDGE TRANSFER STATEMENT: The results of this randomized controlled trial indicate that dentifrices containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and polyphenol-rich cranberry extracts were able to beneficially modulate the microbial ecology of dental plaque in a group of high caries-risk patients. This could contribute toward lowering the risk of developing new caries lesions, an important goal sought by patients, clinicians, and policy makers.
Assuntos
Cárie Dentária , Placa Dentária , Vaccinium macrocarpon , Austrália , Caseínas , Corynebacterium , Humanos , Neisseria , Extratos Vegetais , Remineralização Dentária , VeillonellaRESUMO
BACKGROUND: The most recent documented Australian outbreak of enterovirus A71 (EV-A71) occurred in Sydney from 2012 to 2013. Over a four-month period more than 100 children presented to four paediatric hospitals with encephalitic presentations including fever and myoclonic jerks. The heterogeneous presentations included typical encephalomyelitis, and cardiopulmonary complications. OBJECTIVES: To characterise the genomes of enterovirus strains circulating during the 2013 Sydney EV-A71 outbreak and determine their phylogeny, phylogeography and association between genome and clinical phenotype. STUDY DESIGN: We performed an analysis of enterovirus (EV) positive specimens from children presenting to hospitals in the greater Sydney region of Australia during the 2013 outbreak. We amplified near full-length genomes of EV, and used next generation sequencing technology to sequence the virus. We used phylogenetic/phylogeographic analysis to characterize the outbreak viruses. RESULTS: We amplified and sequenced 23/63 (37 %) genomes, and identified the majority (61 %) as EV-A71. The EV-A71 sequences showed high level sequence homology to C4a genogroups of EV-A71 circulating in China and Vietnam during 2012-13. Phylogenetic analysis showed EV-A71 strains associated with more severe symptoms, including encephalitis or cardiopulmonary failure, grouped together more closely than those from patients with hand, foot and mouth disease. Amongst the non-EV-A71 sequences were five other EV subtypes (representing enterovirus subtypes A and B), reflecting the diversity of EV co-circulation within the community. CONCLUSIONS: This is the first Australian study investigating the near full-length genome of EV strains identified during a known outbreak of EV-A71. EV-A71 sequences were very similar to strains circulating in Asia during the same time period. Whole genome sequencing offers additional information over routine diagnostic testing such as characterisation of emerging recombinant strains and inform vaccine design.
Assuntos
Surtos de Doenças , Enterovirus Humano A/genética , Infecções por Enterovirus/epidemiologia , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Austrália/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Cidades/epidemiologia , Enterovirus Humano A/classificação , Enterovirus Humano A/patogenicidade , Infecções por Enterovirus/virologia , Feminino , Variação Genética , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Filogeografia , Vietnã/epidemiologiaRESUMO
Contemporary caries prevention protocols recommend not only effective remineralizing agents but also ecological measures to reverse the dental plaque dysbiosis responsible for the disease pathogenesis. There is a high-level of evidence supporting the remineralizing efficacy of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) from studies around the world. Evidence is now emerging that CPP-ACP may also have a beneficial influence on the dental plaque microbial ecology and homeostasis. The ecological cariostatic effects of CPP-ACP are believed to be mediated predominantly through its anti-adhesion, buffering and biofilm disrupting actions. This review principally discusses the ecological mechanisms of CPP-ACP and presents the current evidence for its effects on the oral microbiome ecology.
Assuntos
Cariostáticos/farmacologia , Caseínas , Cárie Dentária , Fosfatos de Cálcio , Caseínas/farmacologia , Cárie Dentária/prevenção & controle , Esmalte Dentário , Humanos , Fosfopeptídeos , Remineralização DentáriaRESUMO
In this study, we describe wosA, a Proteus mirabilis gene identified by its ability to increase swarming motility when overexpressed. At various times during the swarming cycle, the increased expression of wosA resulted in a 4- to 16-fold upregulation of the transcription of flhDC, encoding the master regulator of the flagellar cascade. In turn, the expression of flaA, encoding flagellin, was substantially increased in wosA-overexpressing strains. The overexpression of wosA also resulted in constitutive swarmer cell differentiation in liquid medium, a normally nonpermissive condition. However, in wosA-overexpressing strains, the onset of swarming was not altered. A null wosA allele resulted in a slight decrease in swarming motility. The expression of wosA was growth phase dependent during growth in liquid and on agar plates during swarmer cell differentiation. Increasing the viscosity of liquid medium by the addition of polyvinylpyrrolidone induced swarmer cell differentiation and resulted in a fourfold increase in wosA transcription. A fliL mutation that results in constitutive swarmer cell elongation also increased wosA transcription. In this study, we discuss the possible role of the wosA gene product in signal transduction from solid surfaces to induce swarmer cell differentiation, possibly via alterations in the motor switch complex. This study also suggests that despite constitutive swarmer cell differentiation in wosA-overexpressing strains, there are additional regulatory and/or environmental conditions that may control the onset of swarming migration.
Assuntos
Proteínas de Bactérias/genética , Óperon/genética , Proteus mirabilis/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/fisiologia , Northern Blotting , Flagelos/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutação , Povidona/farmacologia , Proteus mirabilis/crescimento & desenvolvimento , Proteus mirabilis/metabolismo , Transcrição Gênica/efeitos dos fármacosRESUMO
Bisphosphonates are effective therapy for osteoporosis, Paget's disease, and metastatic bone disease. Generally, the side effects of bisphosphonates are minimal. Recently, an uncommon adverse reaction affecting the maxilla or mandible, called osteonecrosis of the jaw, has been reported, especially in those patients receiving high doses of bisphosphonates in the oncology setting. Regarding doses used to treat osteoporosis, clinicians must keep the very small potential absolute risk of jaw osteonecrosis in perspective and consider it in relation to the demonstrated benefit of bisphosphonates. Still, in a very small number of patients taking bisphosphonates, intractable, painful, nonhealing exposed bone may occur following dental extractions or denture irritation.