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1.
Int J Mol Sci ; 25(1)2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38203579

RESUMEN

Diabetic foot infections (DFIs) are frequently linked to diabetic-related morbidity and death because of the ineffectiveness of conventional antibiotics against multidrug-resistant bacteria. Pexiganan and nisin A are antimicrobial peptides (AMPs), and their application may complement conventional antibiotics in DFI treatment. A collagen 3D model, previously established to mimic a soft-tissue collagen matrix, was used to evaluate the antibacterial efficacy of a guar gum gel containing pexiganan and nisin alone and combined with three antimicrobials toward the biofilms of Staphylococcus aureus and Pseudomonas aeruginosa isolated from infected foot ulcers. Antimicrobials and bacterial diffusion were confirmed by spot-on-lawn and bacterial growth by bacterial count (cfu/mL). Our main conclusion was that the dual-AMP biogel combined with gentamicin, clindamycin, or vancomycin was not able to significantly reduce bacterial growth or eradicate S. aureus and P. aeruginosa DFI isolates. We further reported an antagonism between dual-AMP and dual-AMP combined with antibiotics against S. aureus.


Asunto(s)
Enfermedades Transmisibles , Diabetes Mellitus , Pie Diabético , Polineuropatías , Enfermedades de la Piel , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Pie Diabético/tratamiento farmacológico , Staphylococcus aureus , Colágeno
2.
BMC Vet Res ; 14(1): 95, 2018 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-29540169

RESUMEN

BACKGROUND: Most of surgical site infections (SSI) are caused by commensal and pathogenic agents from the patient's microbiota, which may include antibiotic resistant strains. Pre-surgical asepsis of the skin is one of the preventive measures performed to reduce SSI incidence and also antibiotic resistance dissemination. However, in veterinary medicine there is no agreement on which biocide is the most effective. The aim of this study was to evaluate the effectiveness of two pre-surgical skin asepsis protocols in dogs. A total of 46 animals were randomly assigned for an asepsis protocol with an aqueous solution of 7.5% povidone-iodine or with an alcoholic solution of 2% chlorhexidine. For each dog, two skin swab samples were collected at pre-asepsis and post-asepsis, for bacterial quantification by conventional techniques and isolation of methicillin-resistant species. RESULTS: Most samples collected at the post-asepsis did not present bacterial growth, both for the animals subjected to the povidone-iodine (74%) or to the chlorhexidine (70%) protocols. In only 9% of the cases a significant bacterial logarithmic reduction was not observed, indicating possible resistance to these agents. Also, the logarithmic reduction of the bacterial quantification from pre- and post-asepsis time, was not statistically different for povidone-iodine (6.51 ± 1.94 log10) and chlorhexidine (6.46 ± 2.62 log10) protocol. From the 39% pre-asepsis swabs which showed bacterial growth in MRSA modified chromogenic agar medium, only one isolate was identified as Staphylococcus aureus and one as S. epidermidis. False positives were mainly other staphylococci species, as well as Enterobacteriaceae. CONCLUSIONS: Pre-surgical skin asepsis protocols with povidone-iodine or chlorhexidine showed similar efficacy in the elimination of methicillin resistant bacteria and preventing surgical site infections in dogs undergoing surgery.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Clorhexidina/uso terapéutico , Enfermedades de los Perros/prevención & control , Etanol/uso terapéutico , Povidona Yodada/uso terapéutico , Infección de la Herida Quirúrgica/veterinaria , Administración Cutánea , Animales , Antiinfecciosos Locales/administración & dosificación , Clorhexidina/administración & dosificación , Protocolos Clínicos , Perros/cirugía , Etanol/administración & dosificación , Femenino , Masculino , Povidona Yodada/administración & dosificación , Infección de la Herida Quirúrgica/prevención & control
3.
Antonie Van Leeuwenhoek ; 111(11): 2225-2232, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29796774

RESUMEN

Diabetic foot ulcers are a major complication of diabetes and are often colonised by complex bacterial communities, where Staphylococcus aureus is frequently co-present with Pseudomonas aeruginosa. These bacteria interact through quorum sensing, encoded in S. aureus by the accessory gene regulator (agr). Typing and copy number of S. aureus agr were assessed here to give insights on strain variability and possible interspecies influence. As agr is classified in four genetic groups, agr-I, agr-II, agr-III and agr-IV, the agr type of 23 S. aureus diabetic foot ulcers isolates was evaluated by PCR and gene copy number determined by qPCR, including in S. aureus present in polymicrobial infections. agr-I and agr-II were found to be present in 52 and 39% of the isolates, respectively. In two isolates, no agr type was identified, and types III and IV were not detected. Interestingly, agr-II copy number was higher in dual suspensions than in S. aureus single suspension. We conclude that agr type I was the most frequent in clinical centers in Lisbon, and variations in agr-I and agr-II copy numbers were strain specific. Variations in agr copy number in dual suspensions suggests that P. aeruginosa may influence S. aureus agr-II gene regulation, confirming an interaction between these two bacteria. This is a first approach to characterise agr variation in S. aureus from diabetic foot ulcers in vitro.


Asunto(s)
Pie Diabético/microbiología , Staphylococcus aureus/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Dosificación de Gen/genética , Regulación Bacteriana de la Expresión Génica , Humanos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/fisiología , Percepción de Quorum/genética , Percepción de Quorum/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones Estafilocócicas/genética , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/fisiología , Transactivadores/genética , Transactivadores/metabolismo
4.
BMC Vet Res ; 13(1): 58, 2017 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-28222788

RESUMEN

BACKGROUND: Pseudomonas aeruginosa is an important human opportunistic pathogen responsible for fatal nosocomial infections worldwide, and has emerged as a relevant animal pathogen. Treatment options are dramatically decreasing, due to antimicrobial resistance and the microorganism's large versatile genome. Antimicrobial resistance profiles, serotype frequency and genomic profile of unrelated P. aeruginosa isolates of veterinary origin (n = 73), including domesticated, farm, zoo and wild animals mainly from Portugal were studied. The genomic profile, determined by DiversiLab system (Rep-PCR-based technique), was compared with the P. aeruginosa global population structure to evaluate their relatedness. RESULTS: Around 40% of the isolates expressed serotypes O6 (20.5%) and O1 (17.8%). A total of 46.6% of isolates was susceptible to all antimicrobials tested. Isolates obtained from most animals were non-multidrug resistant (86.3%), whereas 11% were multidrug resistant, MDR (non-susceptible to at least one agent in ≥ three antimicrobial categories), and 2.7% extensively drug resistant, XDR (non-susceptible to at least one agent in all but two or fewer antimicrobial categories). Resistance percentages were as follows: amikacin (0.0%), aztreonam (41.1%), cefepime (9.6%), ceftazidime (2.7%), ciprofloxacin (15.1%), colistin (0.0%), gentamicin (12.3%), imipenem (1.4%), meropenem (1.4%), piperacillin + tazobactam (12.3%), ticarcillin (16.4%), ticarcillin + clavulanic acid (17.8%), and tobramycin (1.4%). Animal isolates form a population with a non-clonal epidemic structure indistinguishable from the global P. aeruginosa population structure, where no specific 'animal clonal lineage' was detected. CONCLUSIONS: Serotypes O6 and O1 were the most frequent. Serotype frequency and antimicrobial resistance patterns found in P. aeruginosa from animals were as expected for this species. This study confirms earlier results that P. aeruginosa has a non-clonal population structure, and shows that P. aeruginosa population from animals is homogeneously scattered and indistinguishable from the global population structure.


Asunto(s)
Farmacorresistencia Bacteriana , Infecciones por Pseudomonas/veterinaria , Pseudomonas aeruginosa/efectos de los fármacos , Animales , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Bacteriana Múltiple , Tipificación Molecular/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Portugal , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/clasificación , Pseudomonas aeruginosa/genética , Serotipificación/veterinaria , Especificidad de la Especie
5.
Biopolymers ; 104(1): 1-10, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25363470

RESUMEN

Amidated kyotorphin (L-Tyr-L-Arg-NH2; KTP-NH2) causes analgesia when systemically administered. The lipophilic ibuprofen-conjugated derivative of KTP-NH2 has improved analgesic efficacy. However, fast degradation by peptidases impacts negatively in the pharmacodynamics of these drugs. In this work, selected derivatives of KTP and KTP-NH2 were synthesized to combine lipophilicity and resistance to enzymatic degradation. Eight novel structural modifications were tested for the potential to transverse lipid membranes and to evaluate their efficacy in vivo. The rationale behind the design of the pool of the eight selected molecules consisted in the addition of individual group at the N-terminus, namely the tert-butyloxycarbonyl (Boc), γ-aminobutyric acid (GABA), acetyl, butanoyl, and propanoyl or in the substitution of the tyrosine residue by an indole moiety and in the replacement of the peptidic bond by a urea-like bond in some cases. All the drugs used in the study are intrinsically fluorescent, which enables the use of spectrofluorimetry to sample the drugs in the permeation assays. The results show that the BOC and indolyl derivatives of KTP-NH2 have maximal ability to permeate membranes with concomitant maximal analgesic power. Overall, the results demonstrate that membrane permeation is correlated with analgesic efficacy. However, this is not the only factor accounting for analgesia. KTP-NH2 for instance has low passive permeation but is known to have central action. In this case, hypothetical transcytosis over the blood-brain barrier seems to depend on dipeptide transporters.


Asunto(s)
Analgésicos/química , Analgésicos/metabolismo , Endorfinas/química , Endorfinas/metabolismo , Animales , Barrera Hematoencefálica/metabolismo , Humanos , Ácido gamma-Aminobutírico/química
6.
One Health ; 18: 100691, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39010949

RESUMEN

The dissemination of multidrug-resistant (MDR) bacterial isolates in low- and middle-income countries, including several African countries, is a major concern. The poor sanitary conditions of rural and urban families observed in certain regions may favor the transmission of bacterial infections between animals and humans, including those promoted by strains resistant to practically all available antibiotics. In Angola, in particular, the presence of these strains in human hospitals has already been described. Nevertheless, the information on antimicrobial resistance (AMR) prevalence in Angola is still scarce, especially regarding veterinary isolates. This review aimed to synthesize data on antimicrobial resistance in African countries, with a special focus on Angola, from a One Health perspective. The main goals were to identify research gaps that may require further analysis, and to draw attention to the importance of the conscious use of antimicrobials and the establishment of preventive strategies, aiming to guarantee the safeguarding of public health. To understand these issues, the available literature on AMR in Africa was reviewed. We searched PubMed for articles pertinent to AMR in relevant pathogens in Angola and other African countries. In this review, we focused on AMR rates and surveillance capacity. The principal findings were that, in Africa, especially in sub-Saharan countries, AMR incidence is high due to the lack of legislation on antibiotics, to the close interaction of humans with animals and the environment, and to poverty. The information about current resistance patterns of common pathogenic bacteria is sparse, and the number of quality studies is limited in Angola and in some other Sub-Saharan African countries. Also, studies on the "One Health Approach" focusing on the environment, animals, and humans, are scarce in Africa. The surveillance capacity is minimal, and only a low number of AMR surveillance programs and national health programs are implemented. Most international and cooperative surveillance programs, when implemented, are not properly followed, concluded, nor reported. In Angola, the national health plan does not include AMR control, and there is a consistent omission of data submitted to international surveillance programs. By identifying One Health strengths of each country, AMR can be controlled with a multisectoral approach and governmental commitment.

7.
Sci Rep ; 14(1): 8039, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580725

RESUMEN

This study aimed to characterize the antimicrobial resistance (AMR) and virulence profiles of 67 Escherichia coli isolates obtained from faecal samples of 77 wild mammals from 19 different species, admitted in two rescue and rehabilitation centers in Costa Rica. It was possible to classify 48% (n = 32) of the isolates as multidrug-resistant, and while the highest resistance levels were found towards commonly prescribed antimicrobials, resistance to fluoroquinolones and third generation cephalosporins were also observed. Isolates obtained from samples of rehabilitated animals or animals treated with antibiotics were found to have significantly higher AMR levels, with the former also having a significant association with a multidrug-resistance profile. Additionally, the isolates displayed the capacity to produce α-haemolysins (n = 64, 96%), biofilms (n = 51, 76%) and protease (n = 21, 31%). Our results showed that AMR might be a widespread phenomenon within Costa Rican wildlife and that both free-ranging and rehabilitated wild mammals are potential carriers of bacteria with important resistance and virulence profiles. These results highlight the need to study potential sources of resistance determinants to wildlife, and to determine if wild animals can disseminate resistant bacteria in the environment, potentially posing a significant threat to public health and hindering the implementation of a "One Health" approach.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli , Animales , Costa Rica , Salud Pública , Farmacorresistencia Bacteriana , Mamíferos , Animales Salvajes/microbiología , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/microbiología , Antibacterianos/farmacología , Bacterias , Centros de Rehabilitación
8.
Antibiotics (Basel) ; 12(3)2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36978373

RESUMEN

The first research on the insect Galleria mellonella was published 85 years ago, and the larva is now widely used as a model to study infections caused by bacterial and fungal pathogens, for screening new antimicrobials, to study the adjacent immune response in co-infections or in host-pathogen interaction, as well as in a toxicity model. The immune system of the G. mellonella model shows remarkable similarities with mammals. Furthermore, results from G. mellonella correlate positively with mammalian models and with other invertebrate models. Unlike other invertebrate models, G. mellonella can withstand temperatures of 37 °C, and its handling and experimental procedures are simpler. Despite having some disadvantages, G. mellonella is a virtuous in vivo model to be used in preclinical studies, as an intermediate model between in vitro and mammalian in vivo studies, and is a great example on how to apply the bioethics principle of the 3Rs (Replacement, Reduction, and Refinement) in animal experimentation. This review aims to discuss the progress of the G. mellonella model, highlighting the key aspects of its use, including experimental design considerations and the necessity to standardize them. A different score in the "cocoon" category included in the G. mellonella Health Index Scoring System is also proposed.

9.
AIMS Microbiol ; 9(4): 612-646, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38173971

RESUMEN

This review addresses the topic of biofilms, including their development and the interaction between different counterparts. There is evidence that various diseases, such as cystic fibrosis, otitis media, diabetic foot wound infections, and certain cancers, are promoted and aggravated by the presence of polymicrobial biofilms. Biofilms are composed by heterogeneous communities of microorganisms protected by a matrix of polysaccharides. The different types of interactions between microorganisms gives rise to an increased resistance to antimicrobials and to the host's defense mechanisms, with the consequent worsening of disease symptoms. Therefore, infections caused by polymicrobial biofilms affecting different human organs and systems will be discussed, as well as the role of the interactions between the gram-negative bacteria Pseudomonas aeruginosa, which is at the base of major polymicrobial infections, and other bacteria, fungi, and viruses in the establishment of human infections and diseases. Considering that polymicrobial biofilms are key to bacterial pathogenicity, it is fundamental to evaluate which microbes are involved in a certain disease to convey an appropriate and efficacious antimicrobial therapy.

10.
Life (Basel) ; 13(2)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36836861

RESUMEN

Diabetes mellitus (DM) patients frequently develop diabetic foot ulcers (DFU) which are generally infected by a community of microorganisms, mainly Staphylococcus aureus and Pseudomonas aeruginosa. These bacteria exhibit a multi-drug resistance profile and biofilm-forming ability which represent a hurdle in the treatment of diabetic foot infections (DFI). We aimed to evaluate the potential of Nisin Z, an antimicrobial peptide (AMP), as an alternative treatment for severe DFI. Nisin Z shows antibacterial activity against Gram-positive and Gram-negative bacteria and an increased antibacterial effect against Gram-negatives when added to EDTA. As such, Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), Minimum Biofilm Inhibitory Concentration (MBIC), and Minimum Biofilm Eradication Concentration (MBEC) were determined for Nisin Z, Nisin Z + EDTA (0.4%), and Nisin Z + EDTA incorporated into guar gum, in order to test its efficacy against S. aureus and P. aeruginosa isolated from the same DFU. Results showed that Nisin Z added to the chelation agent EDTA displayed higher antibacterial and bacteriostatic efficacy against mono and dual co-cultures of S. aureus and P. aeruginosa, and higher antibiofilm efficiency against monocultures. Nisin Z was moderately cytotoxic at 200 µg/mL. Prospect in vivo studies are needed to confirm the potential of Nisin Z supplemented with EDTA to be used as a complement to conventional antibiotic therapy for severe DFI.

11.
Antibiotics (Basel) ; 12(5)2023 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-37237697

RESUMEN

Diabetic foot ulcers (DFU) are a major complication of diabetes mellitus and a public health concern worldwide. The ability of P. aeruginosa to form biofilms is a key factor responsible for the chronicity of diabetic foot infections (DFIs) and frequently associated with the presence of persister cells. These are a subpopulation of phenotypic variants highly tolerant to antibiotics for which new therapeutic alternatives are urgently needed, such as those based on antimicrobial peptides. This study aimed to evaluate the inhibitory effect of nisin Z on P. aeruginosa DFI persisters. To induce the development of a persister state in both planktonic suspensions and biofilms, P. aeruginosa DFI isolates were exposed to carbonyl cyanide m-chlorophenylhydrazone (CCCP) and ciprofloxacin, respectively. After RNA extraction from CCCP-induced persisters, transcriptome analysis was performed to evaluate the differential gene expression between the control, persisters, and persister cells exposed to nisin Z. Nisin Z presented a high inhibitory effect against P. aeruginosa persister cells but was unable to eradicate them when present in established biofilms. Transcriptome analysis revealed that persistence was associated with downregulation of genes related to metabolic processes, cell wall synthesis, and dysregulation of stress response and biofilm formation. After nisin Z treatment, some of the transcriptomic changes induced by persistence were reversed. In conclusion, nisin Z could be considered as a potential complementary therapy for treating P. aeruginosa DFI, but it should be applied as an early treatment or after wound debridement.

12.
Biomedicines ; 11(4)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37189839

RESUMEN

Pseudomonas aeruginosa is an opportunistic bacterial pathogen responsible for multiple hospital- and community-acquired infections, both in human and veterinary medicine. P. aeruginosa persistence in clinical settings is worrisome and is a result of its remarkable flexibility and adaptability. This species exhibits several characteristics that allow it to thrive under different environmental conditions, including the ability to colonize inert materials such as medical equipment and hospital surfaces. P. aeruginosa presents several intrinsic mechanisms of defense that allow it to survive external aggressions, but it is also able to develop strategies and evolve into multiple phenotypes to persevere, which include antimicrobial-tolerant strains, persister cells, and biofilms. Currently, these emergent pathogenic strains are a worldwide problem and a major concern. Biocides are frequently used as a complementary/combination strategy to control the dissemination of P. aeruginosa-resistant strains; however, tolerance to commonly used biocides has also already been reported, representing an impediment to the effective elimination of this important pathogen from clinical settings. This review focuses on the characteristics of P. aeruginosa responsible for its persistence in hospital environments, including those associated with its antibiotic and biocide resistance ability.

13.
Genes (Basel) ; 14(9)2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-37761817

RESUMEN

Faecal Microbiota Transplantation (FMT) is a promising strategy for modulating the gut microbiome. We aimed to assess the effect of the oral administration of capsules containing lyophilised faeces on dogs with diarrhoea for 2 months as well as evaluate their long-term influence on animals' faecal consistency and intestinal microbiome. This pilot study included five dogs: two used as controls and three with diarrhoea. Animals were evaluated for four months by performing a monthly faecal samples collection and physical examination, which included faecal consistency determination using the Bristol scale. The total number of viable bacteria present in the capsules was quantified and their bacterial composition was determined by 16S rRNA gene sequencing, which was also applied to the faecal samples. During the assay, no side effects were reported. Animals' faecal consistency improved and, after ending capsules administration, Bristol scale values remained stable in two of the three animals. The animals' microbiome gradually changed toward a composition associated with a balanced microbiota. After FMT, a slight shift was observed in its composition, but the capsules' influence remained evident during the 4-month period. Capsules administration seems to have a positive effect on the microbiota modulation; however, studies with more animals should be performed to confirm our observations.


Asunto(s)
Microbioma Gastrointestinal , Perros , Animales , Proyectos Piloto , ARN Ribosómico 16S/genética , Heces , Diarrea
14.
Life (Basel) ; 13(8)2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37629495

RESUMEN

Due to poisoning and decline in the food resources of Eurasian vultures, there has been a rise in the number of Griffon (Gyps fulvus) and Cinereous vultures (Aegypius monachus) needing veterinary care. In captivity, vultures often develop oral and other infectious diseases which can affect their survival and the probability of reintroduction in the wild. Therefore, it is important to characterize relevant microbial species present in the oral cavity of vultures, such as Mucor spp. In this work, seven Mucor spp. isolates previously obtained from Gyps fulvus and Aegypius monachus oral swabs collected at two rehabilitation centers in Portugal were characterized regarding their pathogenic enzymatic profile and antimicrobial activity. Isolates were identified by macro and microscopic observation, and PCR and ITS sequencing. Their antimicrobial activity was determined using a collection of pathogenic bacteria and two yeast species. Results showed that 86% of the isolates produced α-hemolysis, 71% expressed DNase, 57% produce lecithinase and lipase, 29% expressed gelatinase, and 29% were biofilm producers. Four isolates showed inhibitory activity against relevant human and veterinary clinical isolates, including Escherichia coli, Enterococcus faecium, Neisseria zoodegmatis, and Staphylococcus aureus. In conclusion, accurate management programs should consider the benefits and disadvantages of Mucor spp. presence in the oral mucosa.

15.
Mol Pharm ; 8(5): 1929-40, 2011 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-21830793

RESUMEN

The pharmaceutical potential of natural analgesic peptides is mainly hampered by their inability to cross the blood-brain barrier, BBB. Increasing peptide-cell membrane affinity through drug design is a promising strategy to overcome this limitation. To address this challenge, we grafted ibuprofen (IBP), a nonsteroidal anti-inflammatory drug, to kyotorphin (l-Tyr-l-Arg, KTP), an analgesic neuropeptide unable to cross BBB. Two new KTP derivatives, IBP-KTP (IbKTP-OH) and IBP-KTP-amide (IbKTP-NH(2)), were synthesized and characterized for membrane interaction, analgesic activity and mechanism of action. Ibuprofen enhanced peptide-membrane interaction, endowing a specificity for anionic fluid bilayers. A direct correlation between anionic lipid affinity and analgesic effect was established, IbKTP-NH(2) being the most potent analgesic (from 25 µmol · kg(-1)). In vitro, IbKTP-NH(2) caused the biggest shift in the membrane surface charge of BBB endothelial cells, as quantified using zeta-potential dynamic light scattering. Our results suggest that IbKTP-NH(2) crosses the BBB and acts by activating both opioid dependent and independent pathways.


Asunto(s)
Analgésicos/química , Antiinflamatorios no Esteroideos/química , Barrera Hematoencefálica/metabolismo , Endorfinas/química , Ibuprofeno/análogos & derivados , Analgésicos/metabolismo , Analgésicos/uso terapéutico , Analgésicos no Narcóticos/química , Analgésicos no Narcóticos/metabolismo , Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/antagonistas & inhibidores , Analgésicos Opioides/química , Analgésicos Opioides/metabolismo , Analgésicos Opioides/uso terapéutico , Animales , Antiinflamatorios no Esteroideos/metabolismo , Antiinflamatorios no Esteroideos/uso terapéutico , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Bovinos , Membrana Celular/química , Membrana Celular/metabolismo , Células Cultivadas , Reactivos de Enlaces Cruzados/química , Diseño de Fármacos , Endorfinas/metabolismo , Endorfinas/uso terapéutico , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ibuprofeno/química , Ibuprofeno/metabolismo , Ibuprofeno/uso terapéutico , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Masculino , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratas , Ratas Wistar
16.
J Clin Microbiol ; 48(1): 101-8, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19864476

RESUMEN

Pneumococci of serotype 19A are increasingly found to be the cause of infection in various geographic regions. We have characterized the serotype 19A isolates (n = 288) found among pneumococci responsible for infections (n = 1,925) and pneumococci recovered from asymptomatic carriers (n = 1,973) in Portugal between 2001 and 2006. We show that despite the existence of serotype 19A clones that have a greater potential to cause invasive disease or an enhanced colonization capacity, the lineage that is increasing as a cause of infection in Portugal is a multiresistant clone that is competent at both. The expanding Denmark(14)-230 clone found in Portugal is disseminated in other Mediterranean countries, where it is also increasingly responsible for invasive infections in both children and adults. The lineages driving the rise of serotype 19A infections in Asia and the United States (sequence type 320 [ST320] and ST199) are either absent or account for only a small proportion of isolates in Portugal. These data highlight the importance of locally circulating clones with the ability to compete in the nasopharyngeal niche in the emergence of the serotype 19A lineages which are an increasing cause of infection in various geographic regions.


Asunto(s)
Técnicas de Tipificación Bacteriana , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/aislamiento & purificación , Adolescente , Adulto , Antibacterianos/farmacología , Niño , Preescolar , Análisis por Conglomerados , Dermatoglifia del ADN , Farmacorresistencia Bacteriana Múltiple , Electroforesis en Gel de Campo Pulsado , Femenino , Genotipo , Humanos , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Fenotipo , Portugal/epidemiología , Prevalencia , Análisis de Secuencia de ADN , Serotipificación , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/genética , Adulto Joven
17.
J Forensic Sci ; 64(5): 1304-1311, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30801721

RESUMEN

Most emerging or re-emerging infections are vector-borne or zoonotic and can be disseminated worldwide by infected humans or animals. They are a major public health problem and cause a great impact on economy. Zoonotic outbreaks began to be characterized in the 90s, after the creation of Europol and the FBI. Such investigations are carried by forensic pathologists and other specialists to determine whether an outbreak is natural or deliberate. This review will discuss ten zoonotic outbreaks nonrelated to wars focusing on forensic management. In conclusion, some points should be highlighted in the management of a zoonotic outbreak: (i) its diagnosis and detection by forensic pathologists and the coordination of efforts between other specialists are key factors; (ii) communication guidelines and an efficient healthcare system are crucial for any emergency response; (iii) biosafety of all specialists involved must be guaranteed.


Asunto(s)
Brotes de Enfermedades , Zoonosis/epidemiología , Animales , Carbunco/epidemiología , Carbunco/transmisión , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/transmisión , Fiebre Aftosa/epidemiología , Fiebre Aftosa/transmisión , Medicina Legal , Gastroenteritis/epidemiología , Gastroenteritis/microbiología , Síndrome Pulmonar por Hantavirus/epidemiología , Síndrome Pulmonar por Hantavirus/transmisión , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/transmisión , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Infecciones por Salmonella/epidemiología , Infecciones por Salmonella/transmisión , Escherichia coli Shiga-Toxigénica , Tularemia/epidemiología , Tularemia/transmisión , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/transmisión
18.
BMC Microbiol ; 8: 41, 2008 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-18307767

RESUMEN

BACKGROUND: Pili were recently recognized in Streptococcus pneumoniae and implicated in the virulence of this bacterium, which led to the proposal of using these antigens in a future pneumococcal vaccine. However, pili were found to be encoded by the rlrA islet that was not universally distributed in the species. We examined the distribution of the pilus islet, using the presence of the rlrA gene as a marker for the locus, among a collection of invasive isolates recovered in Portugal and analyzed its association with capsular serotypes, clusters defined by the pulsed-field gel electrophoretic profiles (PFGE) and multilocus sequence types. RESULTS: Only a minority of the isolates were positive for the presence of the rlrA gene (27%). There was a high correspondence between the serotype and the presence or absence of rlrA (Wallace coefficient, W = 0.778). In particular, there was an association between the presence of rlrA and the vaccine serotypes 4, 6B, 9V and 14 whereas the gene was significantly absent from other serotypes, namely 1, 7F, 8, 12B and 23F, a group that included a vaccine serotype (23F) and serotype 1 associated with enhanced invasiveness. Even within serotypes, there was variation in the presence of the pilus islet between PFGE clones and a higher Wallace coefficient (W = 0.939) indicates that carriage of the islet is a clonal property of pneumococci. Analysis of rlrA negative isolates revealed heterogeneity in the genomic region downstream of the rfl gene, the region where the islet is found in other isolates, compatible with recent loss of the islet in some lineages. CONCLUSION: The pilus islet is present in a minority of pneumococcal isolates recovered from human invasive infections and is therefore not an essential virulence factor in these infections. Carriage of the pilus islet is a clonal property of pneumococci that may vary between isolates expressing the same serotype and loss and acquisition of the islet may be ongoing.


Asunto(s)
Proteínas Bacterianas/genética , Fimbrias Bacterianas/genética , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/genética , Transactivadores/genética , Adulto , Preescolar , Electroforesis en Gel de Campo Pulsado , Humanos , Portugal , Análisis de Secuencia , Serotipificación , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/patogenicidad , Virulencia
19.
Environ Sci Pollut Res Int ; 23(14): 14671-5, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27236442

RESUMEN

Reutilization of effluents from wastewater treatment plants (WWTP) for non-potable applications is increasing due to the reduction of sustainable water resources. These products mostly come from municipal WWTP and also from slaughterhouses effluents. The microbiological certification of these products is mandatory before their discharge into the environment. This study evaluates if the treatment applied in WWTP to municipal waters or to poultry slaughterhouse effluents distributed over the Portuguese continental territory is efficient in reducing the microbiological risk associated with the reutilization of those wastewaters and sludges. Fecal indicators Escherichia coli and enterococci were evaluated in 42 and 24 wastewater samples from 14 municipal WWTP and 8 poultry slaughterhouse treatment plants, respectively, by the conventional culture method and a rapid Fluorescent in situ hybridization (FISH) technique. Bacterial enumeration in inflow water from most WWTP was rather high (generally >10(5) cells/ml), for both E. coli and Enterococcus spp., and the bacterial quantification by FISH was generally higher than enumeration by the conventional culture method. In both types of treatment plants studied, bacterial load from effluents and sludges was not statistically different from the inflows, indicating that the treatment applied seems to be equally unable to reduce the microbiological load of the effluents. These findings may jeopardize the safe reuse of treated wastewaters in agriculture and the quality of the water environment. Therefore, products like water, sewage sludge, and biosolids originated from the municipal and slaughterhouse WWTP studied should not be reutilized, and effluents treatment should be urgently reviewed.


Asunto(s)
Heces/microbiología , Aguas Residuales/microbiología , Mataderos , Agricultura , Animales , Enterococcus , Escherichia coli/genética , Hibridación Fluorescente in Situ , Portugal , Aves de Corral , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos
20.
ACS Chem Neurosci ; 7(8): 1130-40, 2016 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-27244291

RESUMEN

Kyotorphin (KTP) is an endogenous peptide with analgesic properties when administered into the central nervous system (CNS). Its amidated form (l-Tyr-l-Arg-NH2; KTP-NH2) has improved analgesic efficacy after systemic administration, suggesting blood-brain barrier (BBB) crossing. KTP-NH2 also has anti-inflammatory action impacting on microcirculation. In this work, selected derivatives of KTP-NH2 were synthesized to improve lipophilicity and resistance to enzymatic degradation while introducing only minor changes in the chemical structure: N-terminal methylation and/or use of d amino acid residues. Intravital microscopy data show that KTP-NH2 having a d-Tyr residue, KTP-NH2-DL, efficiently decreases the number of leukocyte rolling in a murine model of inflammation induced by bacterial lipopolysaccharide (LPS): down to 46% after 30 min with 96 µM KTP-NH2-DL. The same molecule has lower ability to permeate membranes (relative permeability of 0.38) and no significant activity in a behavioral test which evaluates thermal nociception (hot-plate test). On the contrary, methylated isomers at 96 µM increase leukocyte rolling up to nearly 5-fold after 30 min, suggesting a proinflammatory activity. They have maximal ability to permeate membranes (relative permeability of 0.8) and induce long-lasting antinociception.


Asunto(s)
Analgésicos/farmacología , Dipeptidasas/farmacología , Endorfinas/química , Endotelio/efectos de los fármacos , Microcirculación/efectos de los fármacos , Animales , Antiinflamatorios , Barrera Hematoencefálica , Dipeptidasas/síntesis química , Dipeptidasas/uso terapéutico , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Endorfinas/farmacología , Hiperalgesia/tratamiento farmacológico , Leucocitos/efectos de los fármacos , Masculino , Ratones , Ratas , Factores de Tiempo
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