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1.
J Appl Microbiol ; 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38244225

RESUMEN

AIM: Hospital-acquired infections (HAIs) caused by antimicrobial-resistant ESKAPE pathogens are a significant concern for the healthcare industry, with an estimated cost of up to ${\$}$45 billion per year in the US alone. Clostridioides difficile is an additional opportunistic pathogen that also poses a serious threat to immunocompromised patients in hospitals. Infections caused by these pathogens lead to increased hospital stays and repeated readmission, resulting in a significant economic burden. Disinfectants and sporicidals are essential to reduce the risk of these pathogens in hospitals, but commercially available products can have a number of disadvantages including inefficacy, long contact times, short shelf lives, and operator health hazards. In this study we evaluated the effectiveness of Rosin (a natural substance secreted by coniferous trees as a defence mechanism against wounds in tree bark) and its commercial derivative Rosetax-21 as disinfectants and sporicidal against the six ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) and spore preparations from Clostridioides difficile. METHODS AND RESULTS: Both Rosin and Rosetax-21 were tested under simulated clean and dirty conditions (with BSA) against the ESKAPE pathogens, and C. difficile spore preparations. In clean conditions, Rosin (5% weight/volume: w/v) demonstrated significant efficacy against five of the ESKAPE pathogens, with A. baumannii and E. faecium being the most susceptible, and K. pneumoniae the most resistant, showing only a one-log reduction after a 5 min treatment. However, in dirty conditions, all pathogens including K. pneumoniae exhibited at least a 3-log reduction to Rosin within 5 min. Rosetax-21 (5% w/v) was found to be less effective than Rosin in clean conditions, a trend that was exacerbated in the presence of BSA. Additionally, both Rosin and Rosetax-21 at 2.5% (w/v) achieved complete eradication of C. difficile spores when combined with 0.5% glutaraldehyde, though their standalone sporicidal activity was limited. CONCLUSIONS: The findings from this study highlight the potential of Rosin and Rosetax-21 as both bactericidal and sporicidal disinfectants, with their efficacy varying based on the conditions and the pathogens tested. This presents an avenue for the development of novel healthcare disinfection strategies, especially against HAIs caused by antimicrobial-resistant ESKAPE pathogens and C. difficile.

2.
J Crohns Colitis ; 16(1): 79-90, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-34302729

RESUMEN

BACKGROUND AND AIMS: In symptomatic patients with ileoanal pouches, pouchoscopy is needed for accurate diagnosis but is invasive. We aimed to assess the utility of non-invasive gastrointestinal ultrasound and faecal calprotectin in ileoanal pouch patients. METHODS: Patients with an ileoanal pouch were consecutively enrolled in this cross-sectional study from clinics in Victoria, Australia. The pouchitis disease activity index was used as a reference standard. Video-recorded pouchoscopies were reviewed by three gastroenterologists. Pouch, pre-pouch, and cuff biopsies were reviewed by a single pathologist. Ultrasound was performed by a single gastroenterologist transabdominally and transperineally. Faecal calprotectin was measured from morning stool samples. All examiners were blinded to patients' clinical history. RESULTS: A total of 44 participants had a pouchoscopy, of whom 43 had a faecal calprotectin test and 42 had an ultrasound; 17 had pouchitis, 15 had pre-pouch ileitis, and 16 had cuffitis. Pouch wall thickness of <3 mm was 88% sensitive in excluding pouchitis, and pouch wall thickness of ≥4 mm was 87% specific in diagnosing pouchitis. Transabdominal ultrasound had good utility [area under the curve: 0.78] in diagnosing moderate-severe pre-pouch ileitis. Transperineal ultrasound had good utility for the diagnosis of pouchitis [area under the curve: 0.79]. Faecal calprotectin differentiated inflammatory from non-inflammatory pouch disorders, such as irritable pouch syndrome, with an area under the curve of 0.90. Faecal calprotectin <100 µg/g ruled out inflammatory pouch disorders with a sensitivity of 94%. CONCLUSIONS: Faecal calprotectin and ultrasound are accurate and complementary tests to diagnose and localise inflammation of the ileoanal pouch. Prospective studies are needed to validate proposed sonographic indices and calprotectin levels.


Asunto(s)
Reservorios Cólicos , Heces/química , Complejo de Antígeno L1 de Leucocito/análisis , Reservoritis/diagnóstico , Ultrasonografía/métodos , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Victoria
3.
Microbiol Spectr ; 9(3): e0109121, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34935417

RESUMEN

Chemical methods of virus inactivation are used routinely to prevent viral transmission in both a personal hygiene capacity but also in at-risk environments like hospitals. Several virucidal products exist, including hand soaps, gels, and surface disinfectants. Resin acids, which can be derived from tall oil, produced from trees, have been shown to exhibit antibacterial activity. However, whether these products or their derivatives have virucidal activity is unknown. Here, we assessed the capacity of rosin soap to inactivate a panel of pathogenic mammalian viruses in vitro. We show that rosin soap can inactivate human enveloped viruses: influenza A virus (IAV), respiratory syncytial virus, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). For IAV, rosin soap could provide a 100,000-fold reduction in infectivity. However, rosin soap failed to affect the nonenveloped encephalomyocarditis virus (EMCV). The inhibitory effect of rosin soap against IAV infectivity was dependent on its concentration but not on the incubation time or temperature. In all, we demonstrate a novel chemical inactivation method against enveloped viruses, which could be of use for preventing virus infections in certain settings. IMPORTANCE Viruses remain a significant cause of human disease and death, most notably illustrated through the current coronavirus disease 2019 (COVID-19) pandemic. Control of virus infection continues to pose a significant global health challenge to the human population. Viruses can spread through multiple routes, including via environmental and surface contamination, where viruses can remain infectious for days. Methods for inactivating viruses on such surfaces may help mitigate infection. Here, we present evidence identifying a novel virucidal product, rosin soap, which is produced from tall oil from coniferous trees. Rosin soap was able to rapidly and potently inactivate influenza virus and other enveloped viruses.


Asunto(s)
Antivirales/farmacología , Resinas de Plantas/farmacología , Jabones/farmacología , Antivirales/análisis , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza A/crecimiento & desarrollo , Aceites de Plantas/análisis , Aceites de Plantas/farmacología , Resinas de Plantas/análisis , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/crecimiento & desarrollo , Jabones/análisis , Inactivación de Virus/efectos de los fármacos
4.
Afr Health Sci ; 21(3): 1040-1047, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35222565

RESUMEN

BACKGROUND: Fisherfolk have been identified as a key population in the HIV response in Uganda due to high HIV prevalence and low engagement in HIV services. While studies have examined lifestyles and risk, much remains to be understood about help and health seeking experiences, including the combined use of biomedical and traditional health care. OBJECTIVE: To examine the use of biomedical and traditional health care in two fishing communities around Lake Victoria in Uganda. METHODS: Exploratory, in-depth qualitative study involving semi-structured interviews with 42 HIV positive fisherfolk. RESULTS: Prior to HIV diagnosis, participants who described becoming ill sought different forms of help including biomedical treatment prescribed by health workers or self-prescribed; biomedical and herbal medicines together; herbal medicines only; or no form of treatment. Following HIV diagnosis, the majority of participants used ART exclusively, while a smaller number used both ART and traditional care strategies, or reported times when they used alternative therapies instead of ART. Prior to HIV diagnosis, fisherfolk's health care seeking practices inhibited engagement with HIV testing and access to biomedical HIV treatment and care. After HIV diagnosis, most resorted only to using ART. CONCLUSION: Study findings provide insight into how fisherfolk's use of biomedical and traditional care prior to diagnosis influences subsequent engagement with HIV treatment. Efforts are needed to reach fisherfolk through everyday health seeking networks to ensure HIV is diagnosed and treated as early as possible.


Asunto(s)
Infecciones por VIH , Lagos , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Caza , Investigación Cualitativa , Uganda/epidemiología
5.
AAPS PharmSciTech ; 20(8): 315, 2019 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-31591662

RESUMEN

The highly pathogenic avian influenza H5N1 virus continues to spread globally in domestic poultry with sporadic transmission to humans. The possibility for its rapid transmission to humans raised global fears for the virus to gain capacity for human-to-human transmission to start a future pandemic. Through direct contact with infected poultry, it caused the largest number of reported cases of severe disease and death in humans of any avian influenza strains. For pandemic preparedness, use of safe and effective vaccine adjuvants and delivery systems to improve vaccine efficacy are considered imperative. We previously demonstrated CaPtivate's proprietary CaP nanoparticles (CaPNP) as a potent vaccine adjuvant/delivery system with ability to induce both humoral and cell-mediated immune responses against many viral or bacterial infections. In this study, we investigated the delivery of insect cell culture-derived recombinant hemagglutinin protein (HA) of A/H5N1/Vietnam/1203/2004 virus using CaPNP. We evaluated the vaccine immunogenicity in mice following two intramuscular doses of 3 µg antigen combined with escalating doses of CaPNP. Our data showed CaPNP-adjuvanted HA(H5N1) vaccines eliciting significantly higher IgG, hemagglutination inhibition, and virus neutralization titers compared to non-adjuvanted vaccine. Among the four adjuvant doses that were tested, CaPNP at 0.24% final concentration elicited the highest IgG and neutralizing antibody titers. We also evaluated the inflammatory response to CaPNP following a single intramuscular injection in guinea pigs and showed that CaPNP does not induce any systemic reaction or adverse effects. Current data further support our earlier studies demonstrating CaPNP as a safe and an effective adjuvant for influenza vaccines.


Asunto(s)
Anticuerpos Neutralizantes/biosíntesis , Anticuerpos Antivirales/biosíntesis , Fosfatos de Calcio/administración & dosificación , Subtipo H5N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Nanopartículas/administración & dosificación , Adyuvantes Inmunológicos/administración & dosificación , Animales , Femenino , Cobayas , Vacunas contra la Influenza/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Vacunas de Subunidad/administración & dosificación
6.
ANZ J Surg ; 87(10): 795-799, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26572072

RESUMEN

BACKGROUND: Diverting loop ileostomy (DLI) is used following low anterior resections (LAR) or ultra-low anterior resections (ULAR) to reduce anastomotic leak (AL). Preoperative mechanical bowel preparation (MBP) is traditionally used with DLI. However, clearance of the left colon can be achieved with a fleet enema without the physiological compromise of MBP. We aimed to assess colonic transit following DLI in this context. METHODS: A prospective, observational study was performed with patients with rectal cancer undergoing LAR or ULAR in a tertiary colorectal unit with preoperative fleet enema. Radiopaque markers were inserted into the caecum following rectal resection and formation of a DLI with placement confirmed by image intensifier and endoscopy. X-rays were performed at days 1, 3, 5 and 14 post-operation with data collected prospectively. RESULTS: Ten patients (mean age 57, nine males) were enrolled. Mean time to functioning stoma was 1.9 days (range 1-3). There was no movement in the majority of markers in all patients at Day 5 post-operation. In all seven patients with Day 14 X-rays, the majority of markers remained in the right colon. Two patients had delayed AL, with markers found within the pelvis in both of these patients. CONCLUSIONS: This is the first study to assess colonic transit following DLI using fleet enema only, with results suggesting colonic motility is abolished in this setting. The use of a fleet enema without MBP may be sufficient prior to rectal resection surgery when DLI is employed. AL may actually increase colonic transit. Further research is warranted.


Asunto(s)
Fuga Anastomótica/prevención & control , Colon/diagnóstico por imagen , Tránsito Gastrointestinal/fisiología , Ileostomía/efectos adversos , Neoplasias del Recto/cirugía , Recto/cirugía , Adulto , Anciano , Anastomosis Quirúrgica/métodos , Fuga Anastomótica/etiología , Catárticos/metabolismo , Colon/fisiopatología , Colon/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Femenino , Humanos , Ileostomía/métodos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Prospectivos , Radiografía Abdominal , Recto/patología , Recto/fisiopatología , Estomas Quirúrgicos
7.
Adv Biochem Eng Biotechnol ; 148: 161-99, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25636485

RESUMEN

Isoprenoids are a class of compounds derived from the five carbon precursors, dimethylallyl diphosphate, and isopentenyl diphosphate. These molecules present incredible natural chemical diversity, which can be valuable for humans in many aspects such as cosmetics, agriculture, and medicine. However, many terpenoids are only produced in small quantities by their natural hosts and can be difficult to generate synthetically. Therefore, much interest and effort has been directed toward capturing the genetic blueprint for their biochemistry and engineering it into alternative hosts such as plants and algae. These autotrophic organisms are attractive when compared to traditional microbial platforms because of their ability to utilize atmospheric CO2 as a carbon substrate instead of supplied carbon sources like glucose. This chapter will summarize important techniques and strategies for engineering the accumulation of isoprenoid metabolites into higher plants and algae by choosing the correct host, avoiding endogenous regulatory mechanisms, and optimizing potential flux into the target compound. Future endeavors will build on these efforts by fine-tuning product accumulation levels via the vast amount of available "-omic" data and devising metabolic engineering schemes that integrate this into a whole-organism approach. With the development of high-throughput transformation protocols and synthetic biology molecular tools, we have only begun to harness the power and utility of plant and algae metabolic engineering.


Asunto(s)
Chlamydomonas/metabolismo , Proteínas de Plantas/química , Plantas/metabolismo , Terpenos/química , Productos Biológicos/química , Biomasa , Biotecnología/métodos , Carbono/química , Química Farmacéutica/métodos , Diseño de Fármacos , Ingeniería Metabólica/métodos , Extractos Vegetales/química , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Semillas/metabolismo , Factores de Transcripción/metabolismo
8.
J Thromb Thrombolysis ; 36(4): 433-41, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23423816

RESUMEN

We sought to evaluate the safety and efficacy of N-acetylcysteine (NAC) on ischemia and reperfusion in a pig model focusing on cardio-renal protection. High doses of NAC may provide protection from contrast induced nephropathy (CIN). NAC has also been demonstrated to reduce myocardial infarction size and improve left ventricular function after ischemia in both humans and animals studies. In this study we tested the safety and cardiorenal protective efficacy of intracoronary NAC delivered in the radiographic contrast agent in a pig model that simulates the catheter based reperfusion therapy of ST elevation myocardial infarctions. 27 pigs underwent 45 min of ischemia after surgical ligation of distal left descending coronary artery. With coronary reperfusion the animals received at total of 200 mL of the contrast agent Iopamidol with and without NAC to mimic radiographic contrast use during invasive reperfusion therapy. At 24 h the following endpoints were compared: LV function (MRI, echocardiography), myocardial injury (infarct size, area-at-risk, troponin, creatinine kinase) and CIN (creatinine, BUN and renal histology). The effects of NAC on platelet reactivity were also evaluated. Intracoronary administration of NAC administered in the contrast agent is safe. NAC reduces platelet reactivity and there was a trend towards a better cardiac function at 24 h. There was no significant difference in the size of the myocardial infarction. In this model of ischemia-reperfusion high dose NAC did not protect from CIN. High dose intracoronary NAC administered with the radiographic contrast is safe but does not provide significant cardio-renal protection.


Asunto(s)
Acetilcisteína/farmacología , Medios de Contraste/farmacología , Angiografía Coronaria , Depuradores de Radicales Libres/farmacología , Yopamidol/farmacología , Infarto del Miocardio , Daño por Reperfusión Miocárdica , Animales , Modelos Animales de Enfermedad , Femenino , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/tratamiento farmacológico , Daño por Reperfusión Miocárdica/diagnóstico por imagen , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Porcinos
9.
Cardiovasc Diabetol ; 11: 135, 2012 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-23116444

RESUMEN

It has been reported previously that diabetic cardiomyopathy can be inhibited or reverted with chronic zinc supplementation. In the current study, we hypothesized that total cardiac calcium and zinc content is altered in early onset diabetes mellitus characterized in part as hyperglycemia (HG) and that exposure of zinc ion (Zn2+) to isolated cardiomyocytes would enhance contraction-relaxation function in HG more so than in nonHG controls. To better control for differential cardiac myosin isoform expression as occurs in rodents after ß-islet cell necrosis, hypothyroidism was induced in 16 rats resulting in 100% ß-myosin heavy chain expression in the heart. ß-Islet cell necrosis was induced in half of the rats by streptozocin administration. After 6 wks of HG, both HG and nonHG controls rats demonstrated similar myofilament performance measured as thin filament calcium sensitivity, native thin filament velocity in the myosin motility assay and contractile velocity and power. Extracellular Zn2+ reduced cardiomyocyte contractile function in both groups, but enhanced relaxation function significantly in the HG group compared to controls. Most notably, a reduction in diastolic sarcomere length with increasing pacing frequencies, i.e., incomplete relaxation, was more pronounced in the HG compared to controls, but was normalized with extracellular Zn2+ application. This is a novel finding implicating that the detrimental effect of HG on cardiomyocyte Ca2+ regulation can be amelioration by Zn2+. Among the many post-translational modifications examined, only phosphorylation of ryanodine receptor (RyR) at S-2808 was significantly higher in HG compared to nonHG. We did not find in our hypothyroid rats any differentiating effects of HG on myofibrillar protein phosphorylation, lysine acetylation, O-linked N-acetylglucosamine and advanced glycated end-products, which are often implicated as complicating factors in cardiac performance due to HG. Our results suggest that the relaxing effects of Zn2+ on cardiomyocyte function are more pronounced in the HG state due an insulin-dependent effect of enhancing removal of cytosolic Ca2+ via SERCA2a or NCX or by reducing Ca2+ influx via L-type channel or Ca2+ leak through the RyR. Investigations into the effects of Zn2+ on these mechanisms are now underway.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Contracción Miocárdica , Miocitos Cardíacos/metabolismo , Cadenas Pesadas de Miosina/metabolismo , Miosinas Ventriculares/metabolismo , Zinc/metabolismo , Animales , Glucemia/metabolismo , Calcio/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Experimental/fisiopatología , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 1/fisiopatología , Diástole , Regulación de la Expresión Génica , Hipotiroidismo/metabolismo , Hipotiroidismo/fisiopatología , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Masculino , Necrosis , Isoformas de Proteínas , Procesamiento Proteico-Postraduccional , Ratas , Ratas Wistar , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Sarcómeros/efectos de los fármacos , Sarcómeros/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Intercambiador de Sodio-Calcio/metabolismo , Factores de Tiempo
10.
JACC Cardiovasc Interv ; 2(3): 215-21, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19463428

RESUMEN

OBJECTIVES: We sought to evaluate the cardiac and renal effects of an N-acetylcysteine (NAC)-enhanced intracoronary radiographic contrast agent. BACKGROUND: Recent studies suggest that high-dose NAC provides better protection from contrast-induced nephropathy, and the antioxidant properties of NAC may also provide cardiac protection. The use of angiographic contrast agents as a drug delivery vehicle for cardiorenal protection effects has not been investigated. METHODS: In a pig model of prolonged cardiac ischemia-reperfusion, NAC-enhanced contrast medium was tested and compared with iopamidol contrast only. Myocardium and renal function were assessed after 24 h. RESULTS: There was no significant difference in the area-at-risk for myocardial infarction (MI) between contrast only and NAC-enhanced contrast medium. In contrast, MI size was about 40% smaller in NAC-enhanced contrast medium-treated animals. These findings were associated with a significant difference in MI morphology. MIs in the NAC-enhanced contrast medium group had a mottled appearance, whereas in the contrast only group they were homogeneous and had a discrete border zone. These differences could explain a higher incidence of periprocedural ventricular arrhythmias in the NAC-enhanced contrast medium group. Histopathological analysis of the myocardium revealed a reduction in programmed cell death by NAC-enhanced contrast medium that may explain the increase in ischemia tolerance. Last, NAC-enhanced contrast medium administration blunted the rise in serum creatinine levels by about 60% and protected from renotubular apotosis. CONCLUSIONS: NAC-enhanced contrast medium reduces MI size and protects renal function in a pig model of ischemia and reperfusion.


Asunto(s)
Acetilcisteína/farmacología , Angioplastia Coronaria con Balón , Medios de Contraste/farmacología , Depuradores de Radicales Libres/farmacología , Yopamidol/farmacología , Enfermedades Renales/inducido químicamente , Infarto del Miocardio , Acetilcisteína/efectos adversos , Animales , Apoptosis , Medios de Contraste/efectos adversos , Creatinina/sangre , Modelos Animales de Enfermedad , Estudios de Factibilidad , Depuradores de Radicales Libres/efectos adversos , Yopamidol/efectos adversos , Riñón/efectos de los fármacos , Enfermedades Renales/prevención & control , Miocardio , Factores de Riesgo , Porcinos
11.
Chembiochem ; 10(1): 55-62, 2009 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-19089881

RESUMEN

Metallothioneins (MTs) were discovered more than 50 years ago and identified as low-molecular weight, sulfhydryl-rich proteins that were subsequently found to bind zinc predominantly. The binding of seemingly redox inactive zinc ions allows MT to play a central role in oxidoreductive cellular metabolism, cellular zinc distribution and homeostasis. In this interpretive study, we discuss the interaction of MT with physiologically relevant molecules and its effect on zinc-thiolate bonds. These interactions are linked to recent progress in the functional role of MT in cellular zinc transport, energy production, and protection of the organism against oxidative stress and neurodegenerative diseases.


Asunto(s)
Ergotioneína/metabolismo , Metalotioneína/metabolismo , Zinc/metabolismo , Secuencia de Aminoácidos , Animales , Ergotioneína/química , Humanos , Metalotioneína/química , Datos de Secuencia Molecular , Oxidación-Reducción , Selenio/metabolismo
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