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1.
Proc Natl Acad Sci U S A ; 117(46): 29190-29201, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33139552

RESUMO

Nipah virus (NiV) is an emerging bat-borne zoonotic virus that causes near-annual outbreaks of fatal encephalitis in South Asia-one of the most populous regions on Earth. In Bangladesh, infection occurs when people drink date-palm sap contaminated with bat excreta. Outbreaks are sporadic, and the influence of viral dynamics in bats on their temporal and spatial distribution is poorly understood. We analyzed data on host ecology, molecular epidemiology, serological dynamics, and viral genetics to characterize spatiotemporal patterns of NiV dynamics in its wildlife reservoir, Pteropus medius bats, in Bangladesh. We found that NiV transmission occurred throughout the country and throughout the year. Model results indicated that local transmission dynamics were modulated by density-dependent transmission, acquired immunity that is lost over time, and recrudescence. Increased transmission followed multiyear periods of declining seroprevalence due to bat-population turnover and individual loss of humoral immunity. Individual bats had smaller host ranges than other Pteropus species (spp.), although movement data and the discovery of a Malaysia-clade NiV strain in eastern Bangladesh suggest connectivity with bats east of Bangladesh. These data suggest that discrete multiannual local epizootics in bat populations contribute to the sporadic nature of NiV outbreaks in South Asia. At the same time, the broad spatial and temporal extent of NiV transmission, including the recent outbreak in Kerala, India, highlights the continued risk of spillover to humans wherever they may interact with pteropid bats and the importance of limiting opportunities for spillover throughout Pteropus's range.


Assuntos
Quirópteros/virologia , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/transmissão , Infecções por Henipavirus/veterinária , Infecções por Henipavirus/virologia , Vírus Nipah/classificação , Vírus Nipah/genética , Animais , Ásia , Bangladesh/epidemiologia , Surtos de Doenças , Feminino , Especificidade de Hospedeiro , Humanos , Imunidade , Masculino , Modelos Biológicos , Epidemiologia Molecular , Vírus Nipah/imunologia , Filogenia , Zoonoses/epidemiologia , Zoonoses/imunologia , Zoonoses/transmissão , Zoonoses/virologia
2.
BMC Public Health ; 22(1): 565, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35317756

RESUMO

BACKGROUND: The World Health Organization declared the rapid spread of COVID-19 around the world to be a global public health emergency. The spread of the disease is influenced by people's willingness to adopt preventative public health behaviours, such as participation in testing programmes, and risk perception can be an important determinant of engagement in such behaviours. METHODS: In this study, we present the first assessment during the first wave of the pandemic and the early stages of the first UK lockdown in April & May 2020 of how the UK public (N = 778) perceived the usefulness of testing for coronavirus and the factors that influence a person's willingness to test for coronavirus. RESULTS: None of the key demographic characteristics (age, gender, education, disability, vulnerability status, or professional expertise) were significantly related to the respondents' willingness to be tested for coronavirus. However, closely following the news media was positively related to willingness to be tested. Knowledge and perceptions about coronavirus significantly predicted willingness to test, with three significantly contributing factors: worry about the health and social impacts to self and family; personal susceptibility; and concerns about the impacts of coronavirus on specific demographic groups. Views on testing for coronavirus predicted willingness to test, with the most influential factors being importance of testing by need; negative views about widespread testing; and mistrust in doctor's advice about testing. CONCLUSIONS: Implications for effective risk communication and localised public health approaches to encouraging public to put themselves forward for testing are discussed. We strongly advocate for effective communications and localised intervention by public health authorities, using media outlets to ensure that members of the public get tested for SARs-CoV2 when required.


Assuntos
COVID-19 , Influenza Humana , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Humanos , Influenza Humana/epidemiologia , Pandemias/prevenção & controle , RNA Viral , SARS-CoV-2 , Reino Unido/epidemiologia , Voluntários
3.
Mol Cell Probes ; 36: 1-9, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28668278

RESUMO

This paper reports on the LGX fluorometric test for enzymatic MRSA/MSSA detection. It highlights the reasons rhodamines have been overlooked and also strategies to improve the synthesis of rhodamine-peptide conjugates. Evaluation of the LGX test for detection of MRSA/MSSA on surfaces is undertaken in the presence of potentially confounding E. coli and S. epidermidis for the first time.


Assuntos
Corantes Fluorescentes/metabolismo , Staphylococcus aureus/isolamento & purificação , Técnicas de Cocultura , Ciclização , Escherichia coli/isolamento & purificação , Fluorescência , Corantes Fluorescentes/química , Fluorometria , Hidrogênio/química , Metais/química , Oxirredução , Xantonas/química
4.
Org Biomol Chem ; 11(20): 3307-13, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23538748

RESUMO

This article reports the development of a novel fluorometric indicator which shows a rapid response when exposed to coagulase positive Staphylococcus aureus (SA) bacteria (including methicillin sensitive Staphylococcus aureus (MSSA) and methicillin resistant Staphylococcus aureus (MRSA) bacteria). The test is robust and will detect a wide variety of SA strains and there is no significant fluorescence response observed for other species of bacteria commonly found in clinical specimens, including other Staphylococcus bacteria. This research forms the basis of a prototype SA testing kit for the rapid detection of SA within hospital and healthcare environments as an economical prescreen or alternative to the current PCR based testing methodology. Rapid identification of SA carriers will allow hospital infection control teams to be pre-emptive and could significantly reduce the incidence of hospital acquired infections involving this organism.


Assuntos
Infecção Hospitalar/microbiologia , Staphylococcus aureus/isolamento & purificação , Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Hospitais , Estrutura Molecular , Staphylococcus aureus/classificação , Staphylococcus aureus/enzimologia
5.
BMC Complement Altern Med ; 11: 115, 2011 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-22093997

RESUMO

BACKGROUND: Enhancement of antimicrobial plant products e.g. pomegranate extract by copper (II) sulphate is known. Such combinations have applications in various settings, including the identification of novel compositions to study, treat and control infection. METHODS: A combination of white tea (WT) (made allowing 10 minutes infusion time at 100°C) was combined with 4.8 mM copper (II) sulphate and tested for antimicrobial effect on the viability of Staphylococcus aureus NCTC 06571. Comparisons were made with green (GT) and black (BT) teas. A WT sub-fraction (WTF < 1000 Da) was tested with copper (II) sulphate and 4.8 mM vitamin C. pH measurements of samples were taken for controls and to observe any changes due to tea/agent interaction. Catalase was used to investigate hydrogen peroxide release. UV-vis. was used to compare WT and WTF. RESULTS: A 30 minute incubation at room temperature of copper (II) sulphate alone and combined with WT reduced the viability of S. aureus NCTC 06571 by c.a 1 log10 cfu mL-1. GT and BT with copper (II) sulphate negated activity to buffer values. Combined with copper (II) sulphate, vitamin C, WTF and, vitamin C plus WTF all reduced the viability of S. aureus NCTC 06571 by c.a. 3.5 log10 cfu mL-1. Independent experiments showed the results were not due to pH effects. Adding WT or WTF to copper (II) sulphate resulted in increased acidity. Copper (II) sulphate alone and combined with WT required c.a 300 µg mL-1 (final concentration) catalase to restore S. aureus viability, WTF with copper (II) sulphate and added vitamin C required c.a 600 µg mL-1. WT and WTF UV-visible spectra were similar. CONCLUSIONS: WT showed no efficacy in the combinations tested. WTF was enhanced with copper (II) sulphate and further with vitamin C. WT and WTF increased acidity of copper (II) sulphate possibly via the formation of chemical complexes. The difference in WT/WTF absorbance possibly represented substances less concentrated or absent in WTF. Investigations to establish which WTF component/s and in what proportions additives are most effective against target organisms are warranted.


Assuntos
Antibacterianos/farmacologia , Ácido Ascórbico/farmacologia , Sulfato de Cobre/farmacologia , Preparações de Plantas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Chá/química , Concentração de Íons de Hidrogênio , Preparações de Plantas/química , Staphylococcus aureus/crescimento & desenvolvimento
6.
Sci Rep ; 11(1): 5650, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707544

RESUMO

Mycoplasmas are fastidious microorganisms, typically characterised by their restricted metabolism and minimalist genome. Although there is reported evidence that some mycoplasmas can develop biofilms little is known about any differences in metabolism in these organisms between the growth states. A systematic metabolomics approach may help clarify differences associated between planktonic and biofilm associated mycoplasmas. In the current study, the metabolomics of two different mycoplasmas of clinical importance (Mycoplasma pneumoniae and Mycoplasma fermentans) were examined using a novel approach involving nuclear magnetic resonance spectroscopy and principle component analysis. Characterisation of metabolic changes was facilitated through the generation of high-density metabolite data and diffusion-ordered spectroscopy that provided the size and structural information of the molecules under examination. This enabled the discrimination between biofilms and planktonic states for the metabolomic profiles of both organisms. This work identified clear biofilm/planktonic differences in metabolite composition for both clinical mycoplasmas and the outcomes serve to establish a baseline understanding of the changes in metabolism observed in these pathogens in their different growth states. This may offer insight into how these organisms are capable of exploiting and persisting in different niches and so facilitate their survival in the clinical setting.


Assuntos
Biofilmes/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética , Mycoplasma fermentans/metabolismo , Mycoplasma pneumoniae/metabolismo , Plâncton/metabolismo , Difusão , Mycoplasma fermentans/citologia , Mycoplasma fermentans/crescimento & desenvolvimento , Mycoplasma pneumoniae/citologia , Mycoplasma pneumoniae/crescimento & desenvolvimento , Análise de Componente Principal , Soro
7.
Ecohealth ; 18(1): 95-106, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34345998

RESUMO

Current wildlife trade practices in China lead to significant interactions between humans and animals and drive the emergence of zoonotic diseases. The at-risk behaviors, knowledge, and attitudes that influence health-related behaviors in relation to animal contact and safety measures in the trade remain poorly understood. A self-administered questionnaire survey was conducted among 947 adult Internet users in three provinces in southern China to assess knowledge, perceived disease risks, at-risk behaviors, and the association of these factors with other demographic factors among the target population. Few of the participants possessed sufficient knowledge of zoonotic diseases. Although most participants were opposed to the use of wild animal resources, many reported keeping wild animals as pets (30.7%) and eating wild animals (30.5%). The majority of participants (76.3%) believed the disease transmission via wildlife trade, but few connected contact with animals to sickness (18.5%) and only slightly more than half sought post-exposure treatment (54.4%). These results reveal low levels of knowledge and perceived risk regarding disease emergence from the animal-human interactions in wildlife trade and uncover the gaps in knowledge and attitudes as key challenges to the development of health behavior change interventions pertaining to wildlife trade.


Assuntos
Animais Selvagens , Conhecimentos, Atitudes e Prática em Saúde , Animais , China/epidemiologia , Humanos , Conhecimento , Zoonoses/epidemiologia
8.
One Health ; 13: 100301, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34401458

RESUMO

Emerging diseases of zoonotic origin such as COVID-19 are a continuing public health threat in China that lead to a significant socioeconomic burden. This study reviewed the current laws and regulations, government reports and policy documents, and existing literature on zoonotic disease preparedness and prevention across the forestry, agriculture, and public health authorities in China, to articulate the current landscape of potential risks, existing mandates, and gaps. A total of 55 known zoonotic diseases (59 pathogens) are routinely monitored under a multi-sectoral system among humans and domestic and wild animals in China. These diseases have been detected in wild mammals, birds, reptiles, amphibians, and fish or other aquatic animals, the majority of which are transmitted between humans and animals via direct or indirect contact and vectors. However, this current monitoring system covers a limited scope of disease threats and animal host species, warranting expanded review for sources of disease and pathogen with zoonotic potential. In addition, the governance of wild animal protection and utilization and limited knowledge about wild animal trade value chains present challenges for zoonotic disease risk assessment and monitoring, and affect the completeness of mandates and enforcement. A coordinated and collaborative mechanism among different departments is required for the effective monitoring and management of disease emergence and transmission risks in the animal value chains. Moreover, pathogen surveillance among wild animal hosts and human populations outside of the routine monitoring system will fill the data gaps and improve our understanding of future emerging zoonotic threats to achieve disease prevention. The findings and recommendations will advance One Health collaboration across government and non-government stakeholders to optimize monitoring and surveillance, risk management, and emergency responses to known and novel zoonotic threats, and support COVID-19 recovery efforts.

9.
Sci Rep ; 11(1): 11259, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045521

RESUMO

The ability of mycoplasmas to persist on surfaces has been widely acknowledged, despite their fastidious nature. However, the organism's capability to form a recognisable biofilm structure has been identified more recently. In the current study Mycoplasma fermentans was found to adhere to the glass surface forming highly differentiated biofilm structures. The volumes of biofilm microcolonies were quantified and observed to be greater at late growth stage than those at early growth stage. The channel diameters within biofilms were measured with Scanning Electron Microscopy images and found to be consistent with the size observed in Confocal Laser Scanning Microscope images. The combination of imaging methods with 3D visualisation provides key findings that aid understanding of the mycoplasma biofilm formation and true biofilm architecture. The observations reported here provide better understanding of the persistence of these minimalist pathogens in nature and clinical settings.


Assuntos
Biofilmes/crescimento & desenvolvimento , Mycoplasma fermentans , Microscopia Confocal
10.
Ann Clin Microbiol Antimicrob ; 9: 20, 2010 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-20663145

RESUMO

BACKGROUND: Antibiotic resistance is an increasing problem in isolates of Staphylococcus aureus (S. aureus) worldwide. In 2001 The National Health Service in the UK introduced a mandatory bacteraemia surveillance scheme for the reporting of S. aureus and methicillin-resistant S. aureus (MRSA). This surveillance initiative reports on the percentage of isolates that are methicillin resistant. However, resistance to other antibiotics is not currently reported and therefore the scale of emerging resistance is currently unclear in the UK. In this study, multiple antibiotic resistance (MAR) profiles against fourteen antimicrobial drugs were investigated for 705 isolates of S. aureus collected from two European study sites in the UK (London) and Malta. RESULTS: All isolates were susceptible to linezolid, teicoplanin and vancomycin. Multiple antibiotic resistance profiles from both countries were determined, a total of forty-two and forty-five profiles were seen in the UK cohort (MRSA and MSSA respectively) and comparatively, sixty-two and fifty-two profiles were shown in the Maltese group. The largest MAR profile contained six antibiotics (penicillin G, methicillin, erythromycin, ciprofloxacin, clindamycin and clarithromycin) and was observed in the MRSA isolates in both the UK and Maltese cohorts. CONCLUSION: The data presented here suggests that the monitoring of changing resistance profiles locally in maintaining treatment efficacy to resistant pathogens.


Assuntos
Bacteriemia/microbiologia , Farmacorresistência Bacteriana , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Antibacterianos/farmacologia , Humanos , Londres , Malta , Testes de Sensibilidade Microbiana
11.
AIDS Res Ther ; 6: 9, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19486507

RESUMO

BACKGROUND: Successful treatment of HIV-positive patients is fundamental to controlling the progression to AIDS. Causes of treatment failure are either related to drug resistance and/or insufficient drug levels in the blood. Severe side effects, coupled with the intense nature of many regimens, can lead to treatment fatigue and consequently to periodic or permanent non-adherence. Although non-adherence is a recognised problem in HIV treatment, it is still poorly detected in both clinical practice and research and often based on unreliable information such as self-reports, or in a research setting, Medication Events Monitoring System caps or prescription refill rates. To meet the need for having objective information on adherence, we propose a method using viral load and HIV genome sequence data to identify non-adherence amongst patients. PRESENTATION OF THE HYPOTHESIS: With non-adherence operationally defined as a sharp increase in viral load in the absence of mutation, it is hypothesised that periods of non-adherence can be identified retrospectively based on the observed relationship between changes in viral load and mutation. TESTING THE HYPOTHESIS: Spikes in the viral load (VL) can be identified from time periods over which VL rises above the undetectable level to a point at which the VL decreases by a threshold amount. The presence of mutations can be established by comparing each sequence to a reference sequence and by comparing sequences in pairs taken sequentially in time, in order to identify changes within the sequences at or around 'treatment change events'. Observed spikes in VL measurements without mutation in the corresponding sequence data then serve as a proxy indicator of non-adherence. IMPLICATIONS OF THE HYPOTHESIS: It is envisaged that the validation of the hypothesised approach will serve as a first step on the road to clinical practice. The information inferred from clinical data on adherence would be a crucially important feature of treatment prediction tools provided for practitioners to aid daily practice. In addition, distinct characteristics of biological markers routinely used to assess the state of the disease may be identified in the adherent and non-adherent groups. This latter approach would directly help clinicians to differentiate between non-responding and non-adherent patients.

12.
BMC Complement Altern Med ; 9: 23, 2009 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-19635137

RESUMO

BACKGROUND: Recently, natural products have been evaluated as sources of antimicrobial agents with efficacies against a variety of micro-organisms. METHODS: This report describes the antimicrobial activities of pomegranate rind extract (PRE) singularly and in combination with cupric sulphate against methicillin-sensitive and -resistant Staphylococcus aureus (MSSA, MRSA respectively), and Panton-Valentine Leukocidin positive community acquired MSSA (PVL positive CA-MSSA). RESULTS: PRE alone showed limited efficacy against MRSA and MSSA strains. Exposure to copper (II) ions alone for 2 hours resulted in moderate activity of between 102 to 103 log10 cfu mL-1 reduction in growth. This was enhanced by the addition of PRE to 104 log10 cfu mL-1 reduction in growth being observed in 80% of the isolates. However, the PVL positive CA-MSSA strains were more sensitive to copper (II) ions which exhibited moderate activities of between 103 log10 cfu mL-1 reduction in growth for 60% of the isolates. CONCLUSION: PRE, in combination with Cu(II) ions, was seen to exhibit moderate antimicrobial effects against clinical isolates of MSSA, MRSA and PVL positive CA-MSSA isolates. The results of this study indicate that further investigation into the active ingredients of natural products, their mode of action and potential synergism with other antimicrobial agents is warranted. This is the first report of the efficacy of pomegranate against clinical PVL positive CA-MSSA isolates.


Assuntos
Antibacterianos/farmacologia , Cobre/farmacologia , Lythraceae , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Toxinas Bacterianas , Sulfato de Cobre/farmacologia , Sinergismo Farmacológico , Exotoxinas , Frutas , Leucocidinas
13.
Biosaf Health ; 1(2): 84-90, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32501444

RESUMO

Human interaction with animals has been implicated as a primary risk factor for several high impact zoonoses, including many bat-origin viral diseases. However the animal-to-human spillover events that lead to emerging diseases are rarely observed or clinically examined, and the link between specific interactions and spillover risk is poorly understood. To investigate this phenomenon, we conducted biological-behavioral surveillance among rural residents in Yunnan, Guangxi, and Guangdong districts of Southern China, where we have identified a number of SARS-related coronaviruses in bats. Serum samples were tested for four bat-borne coronaviruses using newly developed enzyme-linked immunosorbent assays (ELISA). Survey data were used to characterize associations between human-animal contact and bat coronavirus spillover risk. A total of 1,596 residents were enrolled in the study from 2015 to 2017. Nine participants (0.6%) tested positive for bat coronaviruses. 265 (17%) participants reported severe acute respiratory infections (SARI) and/or influenza-like illness (ILI) symptoms in the past year, which were associated with poultry, carnivore, rodent/shrew, or bat contact, with variability by family income and district of residence. This study provides serological evidence of bat coronavirus spillover in rural communities in Southern China. The low seroprevalence observed in this study suggests that bat coronavirus spillover is a rare event. Nonetheless, this study highlights associations between human-animal interaction and zoonotic spillover risk. These findings can be used to support targeted biological behavioral surveillance in high-risk geographic areas in order to reduce the risk of zoonotic disease emergence.

14.
J Med Microbiol ; 57(Pt 11): 1394-1398, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18927418

RESUMO

Since 1999, the European Antimicrobial Resistance Surveillance System (EARSS) has monitored the rise in infection due to a number of organisms, including meticillin-resistant Staphylococcus aureus (MRSA). The EARSS reported that MRSA infections within intensive care units account for 25-50 % of infections in many central and southern European countries, these included France, Spain, Great Britain, Malta, Greece and Italy. Each country has defined epidemic MRSA (EMRSA) strains; however, the method of spread of these strains from one country to another is unknown. In this current study, DNA profiles of 473 isolates of MRSA collected from the UK and Malta were determined by PFGE. Analysis of the data showed that two countries separated by a large geographical distance had a similar DNA profile pattern. Additionally it was demonstrated that strains of EMRSA normally found in the UK were also found in the Maltese cohort (EMRSA 15 and 16). A distinct DNA profile was found in the Maltese cohort, which may be a local EMRSA, and accounted for 14.4 % of all Maltese isolates. The appearance of the same MRSA and EMRSA profiles in two separate countries suggests that MRSA can be transferred out of their country of origin and potentially establish in a new locality or country.


Assuntos
Resistência a Meticilina , Staphylococcus aureus/isolamento & purificação , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Humanos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Reino Unido
15.
FEMS Immunol Med Microbiol ; 53(3): 300-5, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18554301

RESUMO

Antimicrobial resistance is a major concern in health care and farming settings throughout the world. The level of antimicrobial resistance continues to increase and the requirement for a novel and possibly dramatic change in therapy choices is required. One possible mechanism for overcoming resistance is the actual removal of antimicrobial treatment from the therapeutic armoury. This review examines the potential for success of a policy advocating the reduction of antimicrobial use and additionally the withdrawal of such treatments. Evidence from agriculture suggests that the removal of certain drugs from animal husbandry can result in concomitant falls in certain drug resistances in human patients.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana , Animais , Humanos
16.
Vet Microbiol ; 127(3-4): 309-14, 2008 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-17980518

RESUMO

Mycoplasma ovipneumoniae is considered an emerging veterinary pathogen causing pneumonia in sheep and goats worldwide. Currently it has not been possible to define a growth medium that yields the maximum growth of M. ovipneumoniae within a short incubation period. Growth yields of M. ovipneumoniae in Eaton's medium are variable and not as consistently high as those seen with other Mycoplasma spp. This study investigated the ability of different M. ovipneumoniae field strains to grow in various media formulations, where PPLO broth was replaced by a vegetable protein source, and comparisons were made in terms of strain viability in Eaton's medium. Studies were also conducted to determine the optimal carbohydrate source for use in the M. ovipneumoniae medium. Generally, it was found that different strains showed good growth in all media tested, with growth yields at 24h in TSB-1 medium higher than those observed with Eaton's medium. Growth yields reached 10(8) to 10(9)cfu ml(-1) within 24h for particular field strains, with all strains achieving this growth level within 48-72h.


Assuntos
Contagem de Colônia Microbiana/veterinária , Meios de Cultura/química , Doenças das Cabras/diagnóstico , Mycoplasma ovipneumoniae/crescimento & desenvolvimento , Pneumonia por Mycoplasma/veterinária , Doenças dos Ovinos/diagnóstico , Animais , Contagem de Colônia Microbiana/métodos , Doenças das Cabras/microbiologia , Cabras , Cinética , Mycoplasma ovipneumoniae/isolamento & purificação , Pneumonia por Mycoplasma/diagnóstico , Pneumonia por Mycoplasma/microbiologia , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/microbiologia
17.
BMC Complement Altern Med ; 8: 64, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19077299

RESUMO

BACKGROUND: Punica granatum L. or pomegranates, have been reported to have antimicrobial activity against a range of Gram positive and negative bacteria. Pomegranate formulations containing ferrous salts have enhanced although short-term, antibacteriophage activities which are rapidly diminished owing to instability of the ferrous combination. The aim of this study was to determine the antimicrobial activities of combinations of pomegranate rind extracts (PRE) with a range of metals salts with the added stabiliser vitamin C. METHODS: PRE solutions, prepared by blending rind sections with distilled water prior to sterilisation by autoclaving or filtration, were screened with a disc diffusion assay using penicillin G as a control. Suspension assays were used to determine the antimicrobial activities of PRE alone and in combination with salts of the following metals; Fe (II), Cu (II), Mn (II) or Zn (II), and vitamin C, against a panel of microbes following exposure for 30 mins. The test organisms included Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Proteus mirabilis. RESULTS: The screening assay demonstrated that PRE exhibited activity against the Gram positive organisms at 24 h with no observable effect on any of the Gram negative bacteria. However, after 12 h, zones of inhibition were only observed for Ps. aeruginosa. In contrast, using the suspension assay, addition of Cu (II) salts to PRE solutions extended the activities resulting in no detectable growth being observed for the PRE/Cu (II) combination against E. coli, Ps. aeruginosa and P. mirabilis. Minimal antimicrobial activity was observed following incubation with Fe (II), Mn (II) or Zn (II) salts alone or in combination with PRE against any of the organisms in the test panel. The addition of vitamin C markedly enhanced the activities of both PRE/Fe (II) and PRE/Cu (II) combinations against S. aureus. CONCLUSION: This is the first report demonstrating the enhanced efficacy of PRE/metal salt combinations in the presence of the stabilising agent vitamin C, to which all isolates were sensitive with the exception of B. subtilis. This study has validated the exploration of PRE along with additives such as metal salts and vitamin C as novel antimicrobial combinations.


Assuntos
Anti-Infecciosos/administração & dosagem , Ácido Ascórbico/administração & dosagem , Lythraceae , Metais/administração & dosagem , Extratos Vegetais/administração & dosagem , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Estruturas Vegetais , Proteus mirabilis/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Sais/administração & dosagem , Staphylococcus aureus/efeitos dos fármacos
18.
Vet Microbiol ; 109(1-2): 129-34, 2005 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-15975741

RESUMO

The pattern and kinetics of substrate oxidation by type and recent field strains of Mycoplasma agalactiae, Mycoplasma bovis, Mycoplasma bovigenitalium and Mycoplasma ovine/caprine serogroup 11 were investigated by measurement of oxygen uptake. Metabolism of a range of organic acids, sugars and alcohols was detected. All the test strains were unable to oxidise sugars, glycerol and the organic acids, fumarate, malate and alpha-ketoglutarate (1 mM). All strains oxidised organic acid l-lactate, 2-oxobutyrate and pyruvate and demonstrated the ability to oxidise alcohols, particularly isopropanol, which was oxidised at a high rate and high affinity (0.5 mol/mol isopropanol). Its oxidation was consistent with acetone formation, which may be of important in relation to pathogenicity. All strains oxidised similar substrates, however differences were observed between strains in terms of the relative rates and kinetic values for some substrates.


Assuntos
Doenças dos Bovinos/microbiologia , Mycoplasma/metabolismo , Doenças dos Ovinos/microbiologia , Álcoois , Animais , Arginina/metabolismo , Ácidos Carboxílicos/metabolismo , Bovinos , Contagem de Colônia Microbiana/veterinária , Fermentação , Hidrólise , Cinética , Ovinos
19.
Int Semin Surg Oncol ; 2: 20, 2005 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-16202160

RESUMO

OBJECTIVES: Hepatocellular Carcinoma is the commonest form of cancer in The Gambia, and although Hepatitis B and Hepatitis C are known risk factors, accurate baseline data on Hepatitis B and Hepatitis C distribution in the region are limited. Similarly data including information on the involvement of the viruses in HCC remains unknown. The current study was undertaken to estimate the risk of HCC in relation to HCV and HBV in The Gambia. METHODS: Thirteen patients with histological proven history of HCC and 39 healthy controls were enrolled in the study. Each subject blood was screened individually for anti-HCV using ORTHO HCV 3.0 ELISA test system (Ortho-Clinical Diagnostics, Inc, U.S.A) and for HBsAg using QUADRATECH CHECK 4-HBs one step generation hepatitis B surface antigen test kit (VEDALAB, France) following the manufacturers instructions. RESULTS: HBsAg and anti-HCV was detected in 38.5 % (5/13) and 7.7% (1/39) of the persons with a history of HCC respectively. HBsAg but not anti-HCV was detected in 12.8% (5/39 of the case control subjects. HBsAg and HCV rates among the HCC patients were higher in men than women. Rates were highest in patients 48 years and above (37.5%; 3/8). No patient was found with anti-HCV and anti-HBV. CONCLUSION: These results indicate that the involvement of HBV and HCV in HCC in the country is in a ratio of 5:1 and that these two viruses might be independently involved in the pathogenesis of the disease. The study revealed a statistically significant association (p = 0.04) between HBsAg and HCC patients. The results also indicate that up to 50% of HCC cases in the country may be due to non viral factors and calls for further studies in this regard. These findings call for provision of diagnostic facilities for these viruses in hospitals and for their routine screening in blood banks while intervention programmes should be put in place.

20.
Vet Microbiol ; 170(1-2): 81-8, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24612909

RESUMO

This study investigated the prevalence of nasal carriage of staphylococci in dogs and determined the characteristics of the isolates. A total of 724 dogs from 87 veterinary practices across the mainland UK were screened for carriage of Staphylococcus spp. All isolates were examined for meticillin resistance (MR) and the presence of the mecA gene investigated in those isolates showing resistance. All coagulase-positive staphylococci and MR coagulase-negative staphylococci (MRCoNS) were subjected to antimicrobial susceptibility testing. Spa typing and DNA microarray analysis of resistance and virulence genes was carried out on all MR S. aureus (MRSA) and a subset of meticillin susceptible S. aureus (MSSA). Staphylococci were isolated from 399 (55.1%) of the dogs; only seven (1%) carried MRSA, all of which were identified as the dominant UK healthcare-associated strain (EMRSA-15, ST22). MSSA was identified in 47 (6.5%) dogs, the sequence types of which have been suggested as precursors to successful MRSA clones. Forty (5.5%) dogs carried MRCoNS, while no dogs carried MR S. pseudintermedius, although this is increasingly reported in mainland Europe. Resistance to antimicrobials among the isolates varied between species, with multidrug resistance (MDR) in 87.5% of MRCoNS and 21.8% of coagulase positive staphylococci. Microarray analysis of MRSA and a subset of MSSA isolates identified numerous virulence genes associated with pathogenesis, which are commonly identified in isolates of human origin. However, no isolates carried Panton-Valentine leukocidin (PVL) genes. This study suggests that MRSA carriage is low in the vet visiting dog population, but there is a diverse range of virulence and resistance determinants in canine S. aureus and MRCoNS isolates.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus/fisiologia , Medicina Veterinária/estatística & dados numéricos , Animais , Antibacterianos/farmacologia , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Portador Sadio/veterinária , Cães , Resistência a Múltiplos Medicamentos , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Nariz/microbiologia , Proteínas de Ligação às Penicilinas , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Staphylococcus/patogenicidade , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/fisiologia , Reino Unido , Fatores de Virulência/genética
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