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ABSTRACT: Facial grimacing is used to quantify spontaneous pain in mice and other mammals, but scoring relies on humans with different levels of proficiency. Here, we developed a cloud-based software platform called PainFace ( http://painface.net ) that uses machine learning to detect 4 facial action units of the mouse grimace scale (orbitals, nose, ears, whiskers) and score facial grimaces of black-coated C57BL/6 male and female mice on a 0 to 8 scale. Platform accuracy was validated in 2 different laboratories, with 3 conditions that evoke grimacing-laparotomy surgery, bilateral hindpaw injection of carrageenan, and intraplantar injection of formalin. PainFace can generate up to 1 grimace score per second from a standard 30 frames/s video, making it possible to quantify facial grimacing over time, and operates at a speed that scales with computing power. By analyzing the frequency distribution of grimace scores, we found that mice spent 7x more time in a "high grimace" state following laparotomy surgery relative to sham surgery controls. Our study shows that PainFace reproducibly quantifies facial grimaces indicative of nonevoked spontaneous pain and enables laboratories to standardize and scale-up facial grimace analyses.
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Expressão Facial , Camundongos Endogâmicos C57BL , Medição da Dor , Software , Animais , Camundongos , Feminino , Software/normas , Medição da Dor/métodos , Medição da Dor/normas , Masculino , Dor/diagnósticoRESUMO
Several studies on semiconductor material-based single-band, high-performance photosensitive, and chemically stable photodetectors are available; however, the lack of broad spectral response, device flexibility, and biodegradability prevents them from being used in wearable and flexible electronics. Apart from that, the selection of the device fabrication technique is a very crucial factor nowadays in terms of equipment utilization and environmental friendliness. This report presents a study demonstrating a straightforward solvent- and equipment-free handprint technique for the fabrication of WSe2-Ti3C2TX flexible, biodegradable, robust, and broadband (Vis-NIR) photodetectors. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), UV-visible spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirm the formation of a WSe2-Ti3C2TX film. The WSe2-Ti3C2TX van der Waals heterostructure plays a key role in enhancing the optoelectrical properties. The as-prepared photodetector exhibits efficient broadband response with a photoresponsivity and a detectivity of 0.3 mA W-1 and 6.8 × 1010 Jones, respectively, under NIR (780 nm) irradiation (1.0 V bias). Under various pressure and temperature conditions, the device's flexibility and durability were tested. The biodegradable photodetector prepared through the solvent- and equipment-free handprint technique has the potential to attract significant interest in wearable and flexible electronics in the future.
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Peritoneal dialysis (PD)-associated peritonitis remains a severe complication of PD. Although peritonitis due to Rothia spp. is rare, the treatment recommendations and outcomes are uncertain. Our study aims to review (1) published literature on peritonitis caused by Rothia spp. and (2) reported cases of peritonitis due to Rothia spp. in patients on PD in Australia and New Zealand. A literature search of PubMed, Scopus, Embase and Google Scholar for articles published between January 1949 and February 2022 was conducted. To be eligible, articles had to describe antibiotic therapy and treatment outcomes in all PD patients for peritonitis caused by Rothia or Stomatococcus spp. Data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry of PD patients who developed peritonitis due to Rothia spp. between July 2011 and May 2020 were also reviewed. A total of 12 articles and 28 episodes were identified from the literature search and ANZDATA registry analysis, respectively. Over 60% of the peritonitis cases due to Rothia spp. were from the Rothia mucilaginosa species (8/12 and 17/28, respectively), while Rothia dentocariosa was the second most commonly identified species in both the literature search and the ANZDATA registry analysis (4/12 and 5/28, respectively). A majority 8 (66.7%) of the articles in the literature search employed a combination antibiotic regimen, while the remaining 4 (33.3%) used a single antibiotic regimen. In contrast, most of the episodes, 22 (78.6%) described in the ANZDATA registry analysis, employed a single antibiotic regimen, and only 6 (21.4%) episodes were treated with a combination antibiotic regimen. The duration of antibiotic therapy ranged from 2 to 3 weeks in the literature search, and 1 to 3 weeks in the ANZDATA registry. While no deaths within 30 days of developing peritonitis were reported, catheter removal was reported in three (25%) and two (7.1%) episodes in both the literature search and the ANZDATA registry analysis, respectively, of which the majority occurred in patients treated for ≤2 weeks. PD-associated peritonitis due to Rothia spp. is uncommon and associated with relatively good outcomes. Antibiotic treatment for 3 weeks is associated with better outcomes.
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Diálise Peritoneal , Peritonite , Humanos , Diálise Peritoneal/efeitos adversos , Antibacterianos/uso terapêutico , Resultado do Tratamento , Peritonite/tratamento farmacológico , Peritonite/etiologia , Sistema de Registros , Estudos Multicêntricos como AssuntoRESUMO
The identification of effective pharmacotherapies for traumatic brain injury (TBI) remains a major challenge. Treatment with heparin and its derivatives is associated with neuroprotective effects after experimental TBI; however, the optimal dosage and method of administration, modes of action, and effects on hemorrhage remain unclear. Therefore, this review aimed to systematically evaluate, analyze, and summarize the available literature on the use of heparin and low molecular weight heparins (LMWHs) as treatment options for experimental TBI. We searched two online databases (PubMed and ISI Web of Science) to identify relevant studies. Data pertaining to TBI paradigm, animal subjects, drug administration, and all pathological and behavior outcomes were extracted. Eleven studies met our pre-specified inclusion criteria, and for outcomes with sufficient numbers, data from seven publications were analyzed in a weighted mean difference meta-analysis using a random-effects model. Study quality and risk of bias were also determined. Meta-analysis revealed that heparin and its derivatives decreased brain edema, leukocyte rolling, and vascular permeability, and improved neurological function. Further, treatment did not aggravate hemorrhage. These findings must be interpreted with caution, however, because they were determined from a limited number of studies with substantial heterogeneity. Also, overall study quality was low based on absences of data reporting, and potential publication bias was identified. Importantly, we found that there are insufficient data to evaluate the variables we had hoped to investigate. The beneficial effects of heparin and LMWHs, however, suggest that further pre-clinical studies are warranted.
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Edema Encefálico , Lesões Encefálicas Traumáticas , Animais , Edema Encefálico/tratamento farmacológico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Hemorragia/tratamento farmacológico , Heparina/toxicidade , Heparina de Baixo Peso Molecular/farmacologia , Heparina de Baixo Peso Molecular/uso terapêuticoRESUMO
In the absence of guidelines on the management of peritoneal dialysis (PD)-associated peritonitis in patients on automated peritoneal dialysis (APD), variations in clinical practice potentially exist between PD units that could affect clinical outcomes. This study aimed to document the current practices of treating PD-associated peritonitis in patients on APD across Australia and New Zealand and the reasons for practice variations using a cross-sectional online survey. Of the 62 PD units, 34 medical leads (55%) responded to the survey. When treating APD-associated peritonitis, 21 units (62%) continued patients on APD and administered intraperitoneal (IP) antibiotics in manual daytime exchanges; of these, 17 (81%) considered allowing at least 6 h dwell time for adequate absorption of the IP antibiotics as an important reason for adding manual daytime exchange. Nine units (26%) temporarily switched patients from APD to continuous ambulatory peritoneal dialysis (CAPD); of these, five (55%) reported a lack of pharmacokinetic (PK) data for IP antibiotics in APD, four (44%) reported a shortage of APD-trained nursing staff to perform APD exchanges during hospitalisation and three (33%) reported inadequate time for absorption of IP antibiotics on APD as important reasons for their practice. Four units (12%) continued patients on APD and administered IP antibiotics during APD exchanges; of these, three (75%) believed that PK data available in CAPD could be extrapolated to APD. This study demonstrates wide variations in the management of APD-associated peritonitis in Australia and New Zealand; it points towards the lack of PK on antibiotics used to treat peritonitis as an important reason underpinning practice variations.
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Diálise Peritoneal , Peritonite , Humanos , Diálise Peritoneal/efeitos adversos , Estudos Transversais , Nova Zelândia , Peritonite/tratamento farmacológico , Peritonite/etiologia , Antibacterianos/uso terapêutico , Antibacterianos/farmacocinética , AustráliaRESUMO
The paper-based photodetector has recently captivated a great deal of attention in various opto-electronics applications because of facile, cost effective and green synthesis. Two-dimensional transition metal dichalcogenides materials are promising for photodetection under the broad spectral range. In this work, we have fabricated paper-based device by rubbing the tungsten di-selenide (WSe2) crystals on paper substrate. Low-cost, facile and green synthesis technique was employed to make a high-performance paper-based WSe2photodetector. Paper-based photodetector was fabricated via non-toxic simply rubbing process of WSe2nanosheets on low-cost bio-degradable paper. The photodetector shows good responsivity of 72.5 µA W-1and detectivity at around 2.4 × 107Jones at very low bias (1.0 V) at wavelength of 780 nm, respectively. Due to good photo-absorption strength, photodetector exhibits excellent photo-response over wide wavelength range from visible to near infrared. This device also shows very good flexibility with a stable photo-response. This device shows a general and reliable study for the design of photodetectors that is eco-friendly and cost-effective. Overall studied results of the fabricated device indicate that they have the ability to be used in large-scale preparation of the device.
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The recent coronavirus disease 2019 (COVID-19) outbreak has drawn global attention, affecting millions, disrupting economies and healthcare modalities. With its high infection rate, COVID-19 has caused a colossal health crisis worldwide. While information on the comprehensive nature of this infectious agent, SARS-CoV-2, still remains obscure, ongoing genomic studies have been successful in identifying its genomic sequence and the presenting antigen. These may serve as promising, potential therapeutic targets in the effective management of COVID-19. In an attempt to establish herd immunity, massive efforts have been directed and driven toward developing vaccines against the SARS-CoV-2 pathogen. This review, in this direction, is aimed at providing the current scenario and future perspectives in the development of vaccines against SARS-CoV-2.
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Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/epidemiologia , COVID-19/virologia , Humanos , Imunidade , Imunidade Coletiva , SARS-CoV-2/isolamento & purificação , VacinaçãoRESUMO
Non-communicable, chronic respiratory diseases (CRDs) affect millions of individuals worldwide. The course of these CRDs (asthma, chronic obstructive pulmonary disease, and cystic fibrosis) are often punctuated by microbial infections that may result in hospitalization and are associated with increased risk of morbidity and mortality, as well as reduced quality of life. Interleukin-13 (IL-13) is a key protein that regulates airway inflammation and mucus hypersecretion. There has been much interest in IL-13 from the last two decades. This cytokine is believed to play a decisive role in the exacerbation of inflammation during the course of viral infections, especially, in those with pre-existing CRDs. Here, we discuss the common viral infections in CRDs, as well as the potential role that IL-13 plays in the virus-induced disease pathogenesis of CRDs. We also discuss, in detail, the immune-modulation potential of IL-13 that could be translated to in-depth studies to develop IL-13-based therapeutic entities.
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Influenza Humana/imunologia , Interleucina-13/imunologia , Pneumopatias/imunologia , Doença Crônica , Humanos , Inflamação/imunologia , Inflamação/patologia , Influenza Humana/patologia , Pneumopatias/patologia , Muco/imunologiaRESUMO
BACKGROUND: Clinical studies have reported inconsistent outcomes of glucosamine therapy in osteoarthritis patients. One possible reason could be the use of glucosamine products of varying quality. OBJECTIVE: Hence, this study aimed to assess the quality of glucosamine products marketed in Australia and India. This is the first study to investigate both the content and dissolution profiles of glucosamine products. METHOD: The content and dissolution analysis of Australian (n = 25 brands) and Indian (n = 21 brands) glucosamine products was performed according to the criteria specified in the United States Pharmacopoeia (USP). RESULTS: The quality analysis revealed that 16% and 18% of Australian brands, as well as 24% and 19% of Indian brands, did not fulfil the USP content and dissolution criteria, respectively. In approximately half of these cases, the glucosamine content was only slightly below (<3%) that specified by the USP and dissolution was achieved within 15 min after the duration specified by the USP. CONCLUSIONS: The majority of the brands did meet both the content and dissolution analysis criteria of the USP. The extent of deviation from the specified criteria for the other brands was probably insufficient to account for the significant variability in clinical effects. Hence, the study proposed that inter-patient pharmacokinetic variations in glucosamine could be another potential reason for inconsistent therapeutic effects.
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Glucosamina , Osteoartrite , Austrália , Humanos , Índia , Osteoartrite/tratamento farmacológico , SolubilidadeRESUMO
The objectives of this study were to provide a summary of the pharmacokinetic data of some intraperitoneal (IP) antibiotics that could be used for both empirical and culture-directed therapy, as per the ISPD recommendations, and examine factors to consider when using IP antibiotics for the management of automated peritoneal dialysis (APD)-associated peritonitis. A literature search of PubMed, EMBASE, Scopus, MEDLINE and Google Scholar for articles published between 1998 and 2020 was conducted. To be eligible, articles had to describe the use of antibiotics via the IP route in adult patients ≥18 years old on APD in the context of pharmacokinetic studies or case reports/series. Articles describing the use of IP antibiotics that had been recently reviewed (cefazolin, vancomycin, gentamicin and ceftazidime) or administered for non-APD-associated peritonitis were excluded. A total of 1119 articles were identified, of which 983 abstracts were screened. Seventy-three full-text articles were assessed for eligibility. Eight records were included in the final study. Three reports had pharmacokinetic data in patients on APD without peritonitis. Each of cefepime 15 mg/kg IP, meropenem 0.5 g IP and fosfomycin 4 g IP given in single doses achieved drug plasma concentrations above the minimum inhibitory concentration for treating the susceptible organisms. The remaining five records were case series or reports in patients on APD with peritonitis. While pharmacokinetic data support intermittent cefepime 15 mg/kg IP daily, only meropenem 0.5 g IP and fosfomycin 4 g IP are likely to be effective if given in APD exchanges with dwell times of 15 h. Higher doses may be required in APD with shorter dwell times. Information on therapeutic efficacy was derived from case reports/series in individual patients and without therapeutic drug monitoring. Until more pharmacokinetic data are available on these antibiotics, it would be prudent to shift patients who develop peritonitis on APD to continuous ambulatory peritoneal dialysis, where pharmacokinetic information is more readily available.
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Diálise Peritoneal Ambulatorial Contínua , Diálise Peritoneal , Peritonite , Adolescente , Adulto , Antibacterianos/uso terapêutico , Soluções para Diálise , Humanos , Diálise Peritoneal/efeitos adversos , Peritonite/tratamento farmacológico , Peritonite/etiologiaRESUMO
Inflammation is the result of a complex network of cellular and molecular interactions and mechanisms that facilitate immune protection against intrinsic and extrinsic stimuli, particularly pathogens, to maintain homeostasis and promote tissue healing. However, dysregulation in the immune system elicits excess/abnormal inflammation resulting in unintended tissue damage and causes major inflammatory diseases including asthma, chronic obstructive pulmonary disease, atherosclerosis, inflammatory bowel diseases, sarcoidosis and rheumatoid arthritis. It is now widely accepted that both endoplasmic reticulum (ER) stress and inflammasomes play critical roles in activating inflammatory signalling cascades. Notably, evidence is mounting for the involvement of ER stress in exacerbating inflammasome-induced inflammatory cascades, which may provide a new axis for therapeutic targeting in a range of inflammatory disorders. Here, we comprehensively review the roles, mechanisms and interactions of both ER stress and inflammasomes, as well as their interconnected relationships in inflammatory signalling cascades. We also discuss novel therapeutic strategies that are being developed to treat ER stress- and inflammasome-related inflammatory disorders.
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Asthma is a common, heterogeneous and serious disease, its prevalence has steadily risen in most parts of the world, and the condition is often inadequately controlled in many patients. Hence, there is a major need for new therapeutic approaches. Mild-to-moderate asthma is considered a T-helper cell type-2-mediated inflammatory disorder that develops due to abnormal immune responses to otherwise innocuous allergens. Prolonged exposure to allergens and persistent inflammation results in myofibroblast infiltration and airway remodelling with mucus hypersecretion, airway smooth muscle hypertrophy, and excess collagen deposition. The airways become hyper-responsive to provocation resulting in the characteristic wheezing and obstructed airflow experienced by patients. Extensive research has progressed the understanding of the underlying mechanisms and the development of new treatments for the management of asthma. Here, we review the basis of the disease, covering new areas such as the role of vascularisation and microRNAs, as well as associated potential therapeutic interventions utilising reports from animal and human studies. We also cover novel drug delivery strategies that are being developed to enhance therapeutic efficacy and patient compliance. Potential avenues to explore to improve the future of asthma management are highlighted.
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Alérgenos/imunologia , Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Remodelação das Vias Aéreas , Animais , Asma/genética , Asma/imunologia , Sistemas de Liberação de Medicamentos , Humanos , Adesão à Medicação , MicroRNAs/genéticaRESUMO
OBJECTIVES: Clinical trial data for the efficacy of glucosamine in OA are conflicting. Reportedly, Rotta-manufactured glucosamine products are more likely to be effective, and a possible explanation is greater bioavailability than other brands. Specifically, the aim was to compare the steady-state pharmacokinetics of Rotta- and non-Rotta-manufactured glucosamine products in healthy volunteers and examine the interindividual variability. METHODS: In a crossover design, healthy adult participants ingested 1500 mg/day of a Rotta (DONA powder sachets; imported by Mylan Health, Carole Park, QLD, Australia) and a non-Rotta (glucosamine sulphate 1500 mg one-a-day tablet; Blackmores, Warriewood, NSW, Australia) glucosamine product/brand individually for 6 days. Blood samples were collected immediately before and for 12 h after the ingestion of the last dose of each brand and analysed to determine plasma levels of glucosamine. The pharmacokinetic parameters at steady state [including the minimum (Css min) and maximum (Css max) plasma concentration of glucosamine, time to reach Css max post-dosing (Tss max) and area under the plasma concentration vs time curve (AUCss 0-12)] for each brand were calculated and statistically compared. RESULTS: Fourteen participants [mean age 35.5 years (s.d. 8.8)] were recruited (64.2% males). No significant differences were observed in the pharmacokinetic parameters between the two brands. However, for both brands, the coefficient of variation for Css min, Tss max and AUCss 0-12 exceeded 20%, indicating considerable differences in the parameters between participants. No significant association of the pharmacokinetic parameters was observed with various dosing- and participant-related variables. CONCLUSION: Substantial interindividual differences in the absorption and elimination of glucosamine could be a cause of variable clinical outcomes in OA. TRIAL REGISTRATION: The study was registered with the Australian New Zealand Clinical Trials Registry (http://www.ANZCTR.org.au/ACTRN12618000699268p.aspx), number ACTRN12618000699268p.
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Glucosamina/farmacocinética , Adulto , Estudos Cross-Over , Feminino , Glucosamina/administração & dosagem , Glucosamina/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Pós , Comprimidos , Adulto JovemRESUMO
The ongoing COVID-19 pandemic has placed a spotlight on infectious diseases and their associations with host factors and underlying conditions. New data on the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus are entering the public domain at a rapid rate such that their distillation often lags behind. To minimise weak associations becoming perceived as established paradigms, it is imperative that methodologies and outputs from different studies are appropriately critiqued and compared. In this review, we examine recent data on a potential relationship between smoking and COVID-19. While the causal role of smoking has been firmly demonstrated in regard to lung cancer and chronic obstructive pulmonary disease, such associations have the benefit of decades' worth of multi-centre epidemiological and mechanistic data. From our analysis of the available studies to date, it appears that a relationship is emerging in regard to patients with a smoking history having a higher likelihood of developing more severe symptoms of COVID-19 disease than non-smokers. Data on whether COVID-19 has a greater incidence in smokers than non-smokers is thus far, contradictory and inconclusive. There is therefore a need for some caution to be exercised until further research has been conducted in a wider range of geographical settings with sufficient numbers of patients that have been carefully phenotyped in respect of smoking status and adequate statistical control for confounding factors.
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COVID-19/complicações , COVID-19/epidemiologia , Fumar/efeitos adversos , Humanos , Fatores de RiscoRESUMO
PURPOSE: Glucosamine is widely used by patients with osteoarthritis (OA) to provide symptomatic relief and to delay disease progression. However, clinical studies have reported inconsistent clinical outcomes. The current study hypothesized that the reported inconsistent clinical results could be, in part, due to variable bioavailability and elimination of glucosamine. This study therefore aimed to determine steady-state minimum plasma concentrations (Css min) of glucosamine to examine the variability among patients taking the supplement. METHODS: Patients with OA who had been taking glucosamine for at least 1 week were recruited. Patients' blood samples were collected 24 h after the ingestion of the previous dose to determine Observed Css min and after a 5-day washout period to determine the endogenous glucosamine levels (GlcNend). The Actual Css min was calculated by using the following equation: Actual Css min = Observed Css min - GlcNend. The glucosamine plasma concentrations were determined by using a previously developed HPLC method. FINDINGS: Ninety-one participants (age range, 42-89 years; mean [SD] age, 68.2 [7.6] years) were recruited (70% females). There was substantial (106-fold) variation, with a 45% coefficient of variation, between the Actual Css min levels (3-320 ng/mL) in participants. No significant association of Actual Css min was observed with various dose- and patient-related variables. IMPLICATIONS: The observed high variability in steady-state plasma concentrations indicates substantial inter-patient differences in the absorption and elimination of glucosamine, which could be a cause for inconsistent clinical outcomes in patients with OA.
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Glucosamina/sangue , Osteoartrite/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Disponibilidade Biológica , Suplementos Nutricionais , Feminino , Glucosamina/administração & dosagem , Glucosamina/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Resultado do TratamentoRESUMO
BACKGROUND: Peritonitis is a common and serious complication of peritoneal dialysis (PD). PD-associated peritonitis (PDAP) caused by Pseudomonas is usually resistant to most antibiotics, resulting in high failure rates. Ceftolozane/tazobactam (C/T) has been shown to be effective in treating urinary tract and intra-abdominal infections caused by beta-lactam resistant Pseudomonas and other gram-negative bacteria. Given its favourable adverse effects profile, it has a potential role in the treatment of PDAP caused by Pseudomonas species resistant to other antibiotics. Intraperitoneal administration of antibiotics admixed with PD solutions for the treatment of PDAP is associated with superior outcomes. However, there is a lack of published data on the stability of C/T in PD solutions. Therefore, this study investigated the physical and chemical stability of C/T in commonly used PD solutions at different temperatures. METHODS: A total of 27 PD bags (3 PD bags for each type of PD solution including Dianeal®, Extraneal®, Balance® and Physioneal® PD bags) containing C/T were prepared and stored at 25°C for 6 h, followed by 4°C for 168 h and then 37°C for 12 h. An aliquot from each PD bag was withdrawn, and the concentration of C/T before (0 h) and after predefined time points was determined using a stability-indicating high-performance liquid chromatography assay. Samples were also assessed for pH, colour change and particulate matter immediately after preparation and on each day of analysis. RESULTS: C/T retained more than 97% of their initial concentration when stored at 25°C for 6 h followed by storage at 4°C for 168 h and then at 37°C for 12 h. Particle formation was not detected at any time under the tested storage conditions. The pH and colour remained essentially unchanged throughout the study. CONCLUSIONS: These results provide a platform for clinical studies to determine the safety and therapeutic efficacy of intraperitoneal C/T for the treatment of PDAP caused by resistant Pseudomonas species.
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Diálise Peritoneal , Antibacterianos , Ceftazidima , Cefalosporinas , Soluções para Diálise , Estabilidade de Medicamentos , Humanos , Diálise Peritoneal/efeitos adversos , TazobactamRESUMO
BACKGROUND: For the treatment of peritoneal dialysis-associated peritonitis (PDAP), ceftazidime is routinely admixed with peritoneal dialysis (PD) solutions before its intraperitoneal administration. One of the major degradation products of ceftazidime is pyridine, a potentially toxic compound. Depending on the type of PD solution, ceftazidime is exposed to an environment with acidic or basic pH, and depending on the type of dosing and individual unit practices related to preparation and storage, ceftazidime can be at body temperature for 4-10 h, resulting in potentially varying rates of degradation to pyridine by-product. No study has investigated whether the amount of generated pyridine exceeds the maximum daily exposure limit of 2 mg when ceftazidime-PD admixtures are kept at body temperature. Therefore, the current study aimed to determine the levels of pyridine generated in PD-ceftazidime admixtures kept at 37°C for various time points. METHODS: Ceftazidime was admixed with 2 L Dianeal (1.5%, 2.5% and 4.25% dextrose) and 2 L Physioneal (1.36%, 2.27% and 3.86% glucose) PD solutions to obtain a concentration of 125 mg/L (continuous dosing model) or 500 mg/L (intermittent dosing model). A total of 36 PD admixtures (3 bags for each type of PD solution and 3 bags for each type of dosing) were prepared and stored at 37°C for 10 h. An aliquot was withdrawn at time 0 (baseline) and after 2, 6, 8 and 10 h of storage. The withdrawn samples were then analysed to determine the concentrations of ceftazidime and pyridine using high-performance liquid chromatography. RESULTS: With the intermittent dosing model (500 mg/L), ceftazidime was found to be stable for only 2 and 6 h when admixed with 3.86% and 2.27% glucose Physioneal PD solutions, respectively. While ceftazidime (500 mg/L) retained more than 90% of its initial concentration in the three types of Dianeal and 1.36% dextrose Physioneal solutions for 10 and 8 h, respectively, the generated amount of pyridine ranged between approximately 290% and 371% more than the daily recommended limit. With the continuous dosing model (125 mg/L), ceftazidime was found to be stable for 6 h in all three types of Physioneal PD solutions, but the total amount of generated pyridine with four daily exchanges (6 h each) was estimated to be 170-360% over the daily recommended limit. Ceftazidime (125 mg/L) was chemically stable when admixed with three types of Dianeal PD solutions and stored at 37°C for 10 h, and the levels of pyridine were estimated to be less than the maximum recommended daily limit. CONCLUSIONS: Until the outcomes of this in vitro study are confirmed by appropriate in vivo studies, continuous dosing of ceftzadime-Dianeal admixtures for the treatment of PDAP may be preferred over continuous dosing of ceftazidime-Physioneal admixtures, and intermittent dosing of ceftazidime-Physioneal and ceftazidime-Dianeal admixtures, as ceftazidime remains stable and the generated levels of pyridine are below the maximum recommended daily exposure.
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Antibacterianos/química , Ceftazidima/química , Soluções para Diálise/química , Diálise Peritoneal , Piridinas/análise , Temperatura , Temperatura Corporal , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Humanos , Peritonite/prevenção & controleRESUMO
: Low molecular weight heparins are used during haemodialysis for thromboprophylaxis of the dialysis circuit, with plasma antifactor-Xa (anti-Xa) activity used as a surrogate measure for effective anticoagulation. However, this pharmacokinetic parameter does not always correlate with pharmacodynamic effects in patients. The aim of this study was to investigate the relationship between actual plasma levels of the low molecular weight heparins enoxaparin, anti-Xa activity, and global coagulation measurement of thrombin generation during haemodialysis. Blood was analysed from 16 adult patients with end-stage kidney disease at 0, 2, 4âh, and at completion of 31 dialysis sessions where single fixed doses of 20 (nâ=â3), 40 (nâ=â16), 60 (nâ=â6), or 80 (nâ=â6)âmg of enoxaparin (equating to 0.23-1.07âmg/kg) were used as thromboprophylaxis. Plasma enoxaparin oligosaccharides [degree of polymerization (dp)6-dp16] were measured by high-performance size exclusion chromatography, anti-Xa activity by colourimetric assay, and thrombin generation by calibrated automated thrombogram. Plasma enoxaparin fragments were undetectable at the beginning of each dialysis, peaked at 2âh to levels that correlated with dose (râ=â0.68, Pâ<â0.001) then remained relatively stable. In contrast, therapeutic anti-Xa levels achieved at 2âh in 18 cases (58%) quickly dropped to only six cases (19%) at the end of dialysis, by which time thrombin generation had also recovered in 81% of patients. Statistical modelling revealed a threshold value of anti-Xa at 0.53âIU/ml that supressed thrombin generation to 15.28% of baseline (Pâ<â0.001). Despite loss of anticoagulant activity in the majority of patients, plasma levels of enoxaparin oligosaccharides remained detectable and relatively unchanged throughout dialysis.
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Enoxaparina/sangue , Inibidores do Fator Xa/sangue , Diálise Renal , Trombina/biossíntese , Adulto , Anticoagulantes/sangue , Anticoagulantes/uso terapêutico , Enoxaparina/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Cinética , Pessoa de Meia-Idade , Modelos Estatísticos , Oligossacarídeos/sangueRESUMO
The clinical effect of glucosamine, the most widely used supplement in patients with osteoarthritis, on joint pain and function improvement, is reported to be inconsistent. Inter-patient variability in the pharmacokinetics of glucosamine, especially its oral absorption, could contribute to the inconsistent clinical outcomes. To test this hypothesis, a novel but simple Hydrophilic Interaction Liquid Chromatography coupled with Charged Aerosol Detector method was developed and validated. The sample was prepared by simple protein precipitation and analysed using an amino column and acetonitrile:100â¯mM ammonium formate with gradient elution. The developed method was linear (12.5-800â¯ng/mL, r2â¯=â¯0.999) and the relative standard deviations for intra- and inter-day accuracy, precision and repeatability were all less than 6%. The sensitivity of the method (lower limit of quantitation; 12.5â¯ng/mL) allowed the quantification of endogenous and exogenous glucosamine levels in 12 patients with osteoarthritis, taking 1500â¯mg glucosamine daily. The analysis showed 120-fold variation (81.7% variance) in exogenous glucosamine levels among the patients, indicating that substantial variability in the extent of absorption and/or rate of elimination could be a possible cause for the reported inconsistent clinical outcomes. The newly-developed method was sensitive and can be used to study the pharmacokinetics of glucosamine.