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1.
J Hazard Mater ; 436: 129263, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739781

RESUMO

Leakage and contamination of hazardous chemical substances have been widely recognized as the critical issue in ensuring human health, maintaining environmental sustainability, and safeguarding public security. Urotropin as a crucial raw material in industrial holds a potential threat to aquatic/atmospheric environment with refractory degradation problem, hence, there remains a severe challenge to effectively and on-site monitor urotropin. Here, a general design with all-in-one strategy was presented, in which a highly integrated "pocket sensing chip" combining a sampling unit and a detecting unit together endows a rapid and ultrasensitive colorimetric detection without dead-zone towards urotropin. By loading fast blue B as sensing reagent in the detecting unit, a moderate and sensitive detection towards urotropin via electrostatic interaction was achieved with detection limits of 9 µM for liquid and 17.19 ng for particulates. Furthermore, an expandable sensing chip for the purpose of simultaneously screening on multi-target exhibited remarkable applicability for examining suspicious objects with all sorts of surface in real scenes, being unacted on environmental complexity. We expect this design would provide a universal strategy and the high referential value to propel the development of handy and portable sensing device to efficiently screen the environmental relevant critical substance on-site.


Assuntos
Colorimetria , Metenamina , Substâncias Perigosas , Humanos , Eletricidade Estática
2.
Hypertension ; 79(8): 1814-1823, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35656807

RESUMO

BACKGROUND: Uric acid (UA) concentration within carotid plaque and its association with cerebrovascular events have not been detected or quantified. Systemically, serum UA is a marker of inflammation and risk factor for atherosclerosis. However, its association with carotid plaque instability and stroke pathogenesis remains unclear. In patients undergoing carotid endarterectomy, we aimed to determine whether UA is present differentially in symptomatic versus asymptomatic carotid plaques and whether serum UA is associated with cerebrovascular symptoms (stroke, transient ischemic attack, or amaurosis fugax). METHODS: Carotid atherosclerotic plaques were collected during carotid endarterectomy. The presence of UA was assessed using Gomori methenamine silver staining as well as anti-UA immunohistochemical staining and its quantity measured using an enzymatic colorimetric assay. Clinical information was obtained through a retrospective review of data. RESULTS: UA was more commonly detected in symptomatic (n=23) compared with asymptomatic (n=9) carotid plaques by Gomori methenamine silver (20 [86.9%] versus 2 [22.2%]; P=0.001) and anti-UA immunohistochemistry (16 [69.5%] versus 1 [11.1%]; P=0.004). UA concentration was higher in symptomatic rather than asymptomatic plaques (25.1 [9.5] versus 17.9 [3.8] µg/g; P=0.021). Before carotid endarterectomy, serum UA levels were higher in symptomatic (n=341) compared with asymptomatic (n=146) patients (5.9 [interquartile range, 4.6-6.9] mg/dL versus 5.2 [interquartile range, 4.6-6.2] mg/dL; P=0.009). CONCLUSIONS: The current study supports a potential role of UA as a potential tissue participant and a systemic biomarker in the pathogenesis of carotid atherosclerosis. UA may provide a mechanistic explanation for plaque instability and subsequent ischemic cerebrovascular events.


Assuntos
Estenose das Carótidas , Placa Aterosclerótica , Acidente Vascular Cerebral , Biomarcadores/metabolismo , Estenose das Carótidas/complicações , Estenose das Carótidas/cirurgia , Humanos , Metenamina , Acidente Vascular Cerebral/complicações , Ácido Úrico
3.
Health Technol Assess ; 26(23): 1-172, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35535708

RESUMO

BACKGROUND: Daily, low-dose antibiotic prophylaxis is the current standard care for women with recurrent urinary tract infection. Emerging antimicrobial resistance is a global health concern, prompting research interest in non-antibiotic agents such as methenamine hippurate, but comparative data on their efficacy and safety are lacking. OBJECTIVE: To assess the clinical effectiveness and cost-effectiveness of methenamine hippurate (Hiprex®; Mylan NV, Canonsburg, PA, USA) compared with current standard care (antibiotic prophylaxis) for recurrent urinary tract infection prevention in adult women. DESIGN: Multicentre, pragmatic, open-label, randomised, non-inferiority trial of 12 months' treatment with the allocated intervention, including an early, embedded qualitative study and a 6-month post-treatment observation phase. The predefined non-inferiority margin was one urinary tract infection per person-year. SETTING: Eight UK NHS secondary care sites. PARTICIPANTS: A total of 240 adult women with recurrent urinary tract infection requiring preventative treatment participated in the trial. INTERVENTIONS: A central randomisation system allocated participants 1 : 1 to the experimental (methenamine hippurate: 1 g twice daily) or control (once-daily low-dose antibiotics: 50/100 mg of nitrofurantoin, 100 mg of trimethoprim or 250 mg of cefalexin) arm. Crossover between treatment arms was permitted. MAIN OUTCOME MEASURES: The primary clinical outcome was incidence of symptomatic antibiotic-treated urinary tract infection during the 12-month treatment period. Cost-effectiveness was assessed by incremental cost per quality-adjusted life-year gained, extrapolated over the patient's expected lifetime using a Markov cohort model. Secondary outcomes included post-treatment urinary tract infections, total antibiotic use, microbiologically proven urinary tract infections, antimicrobial resistance, bacteriuria, hospitalisations and treatment satisfaction. RESULTS: Primary modified intention-to-treat analysis comprised 205 (85%) randomised participants [102/120 (85%) participants in the antibiotics arm and 103/120 (86%) participants in the methenamine hippurate arm] with at least 6 months' data available. During treatment, the incidence rate of symptomatic, antibiotic-treated urinary tract infections decreased substantially in both arms to 1.38 episodes per person-year (95% confidence interval 1.05 to 1.72 episodes per person-year) for methenamine hippurate and 0.89 episodes per person year (95% confidence interval 0.65 to 1.12 episodes per person-year) for antibiotics (absolute difference 0.49; 90% confidence interval 0.15 to 0.84). This absolute difference did not exceed the predefined, strict, non-inferiority limit of one urinary tract infection per person-year. On average, methenamine hippurate was less costly and more effective than antibiotics in terms of quality-adjusted life-years gained; however, this finding was not consistent over the longer term. The urinary tract infection incidence rate 6 months after treatment completion was 1.72 episodes per year in the methenamine hippurate arm and 1.19 in the antibiotics arm. During treatment, 52% of urine samples taken during symptomatic urinary tract infections were microbiologically confirmed and higher proportions of participants taking daily antibiotics (46/64; 72%) demonstrated antibiotic resistance in Escherichia coli cultured from perineal swabs than participants in the methenamine hippurate arm (39/70; 56%) (p-value = 0.05). Urine cultures revealed that during treatment higher proportions of participants and samples from the antibiotic arm grew E. coli resistant to trimethoprim/co-trimoxazole and cephalosporins, respectively. Conversely, post treatment, higher proportions of participants in the methenamine hippurate arm (9/45; 20%) demonstrated multidrug resistance in E. coli isolated from perineal swabs than participants in the antibiotic arm (2/39; 5%) (p = 0.06). All other secondary outcomes and adverse events were similar in both arms. LIMITATIONS: This trial could not define whether or not one particular antibiotic was more beneficial, and progressive data loss hampered economic evaluation. CONCLUSIONS: This large, randomised, pragmatic trial in a routine NHS setting has clearly shown that methenamine hippurate is not inferior to current standard care (daily low-dose antibiotics) in preventing recurrent urinary tract infections in women. The results suggest that antimicrobial resistance is proportionally higher in women taking prophylactic antibiotics. RECOMMENDATIONS FOR RESEARCH: Future research should include evaluation of other non-antibiotic preventative treatments in well-defined homogeneous patient groups, preferably with the comparator of daily antibiotics. TRIAL REGISTRATION: This trial is registered as ISRCTN70219762 and EudraCT 2015-003487-36. FUNDING: This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 23. See the NIHR Journals Library website for further project information.


Women with recurrent urine infections often require preventative treatment to reduce the frequency of infection episodes. Daily low-dose antibiotic medication is a guideline-recommended treatment option for these women. There is increasing concern globally regarding antibiotic-resistant infections, which has led researchers to look at alternative treatments. This trial was conducted to find out whether or not taking an alternative treatment that is not an antibiotic [i.e. methenamine hippurate (Hiprex®; Mylan NV, Canonsburg, PA, USA)] was as effective as the standard daily low-dose antibiotics. A total of 240 women from across the UK took part in the trial. They were divided equally into two groups; half of the women were given methenamine hippurate and the other half were given standard low-dose antibiotics. Both treatments were prescribed to be taken every day for 1 year. To make a fair comparison, people were put into the two groups at random using a computer program. Aspects of the trial that could be improved were identified through telephone interviews with patients and recruiting staff. Feedback from these telephone interviews helped to ensure the successful conduct of the trial. Patients were followed up for 18 months, comprising the 12 months when they were taking treatment and a 6-month follow-up phase after they had finished treatment. We found that the non-antibiotic option of methenamine hippurate was no worse than the current standard treatment of daily antibiotics in preventing urinary tract infection episodes in adult women. For both treatments, patients expressed high levels of satisfaction. One advantage of the methenamine hippurate treatment was that infecting bacteria were slightly less likely to develop resistance to antibiotics. We also evaluated health-care costs of both treatments and found that methenamine hippurate seemed worthwhile to the NHS in the short term, but there was uncertainty over longer-term costs and benefits. These results will help patients with repeated urinary tract infections to decide on treatment options, particularly if they want to avoid prolonged courses of preventative antibiotics.


Assuntos
Antibioticoprofilaxia , Infecções Urinárias , Adulto , Antibacterianos/efeitos adversos , Análise Custo-Benefício , Escherichia coli , Feminino , Hipuratos , Humanos , Masculino , Metenamina/análogos & derivados , Trimetoprima , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle
4.
Female Pelvic Med Reconstr Surg ; 28(6): e205-e210, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35536668

RESUMO

IMPORTANCE: Antibiotics are commonly used to treat and prevent urinary tract infection (UTI), but resistance is growing. Nonantibiotic prophylaxis such as methenamine hippurate (MH) shows clinical promise, but its impact on bladder factors influencing recurrent UTIs (rUTIs) is not well described. OBJECTIVE: The aim of the study was to examine the effect of MH on bladder inflammation and barrier function in aged mice and women with rUTI. STUDY DESIGN: This study included urine samples from an experimental study involving aged female mice with and without methenamine treatment as well as women with rUTI who received either no prophylaxis, MH alone, vaginal estrogen therapy and/or d-mannose alone, or MH in addition to vaginal estrogen therapy and/or d-mannose. We performed a comprehensive cytopathological analysis, which included enzyme-linked immunosorbent assay for immunoglobulin A (IgA), interleukin 6 (in human samples), and fluorescein isothiocyanate-conjugated-dextran permeability assay (in mice) to assess for urothelial permeability. RESULTS: In the aged mice model, there was a decreased urothelial permeability (as seen by retention of fluorescein isothiocyanate-conjugated-dextran fluorescence in superficial cells) and increased urinary IgA in mice treated with MH compared with controls. There was no significant difference in urothelial shedding (P > 0.05). In human samples, there was significantly increased urinary IgA in those taking MH alone compared with no prophylaxis (830.1 vs 540.1 ng/mL, P = 0.04), but no significant difference in interleukin 6. CONCLUSIONS: Methenamine hippurate seems to enhance barrier function as evidenced by decreased urothelial permeability and increased urinary IgA levels, without worsening inflammation. This may reflect another beneficial mechanism by which MH helps prevent rUTI.


Assuntos
Cistite , Infecções Urinárias , Animais , Cistite/tratamento farmacológico , Dextranos/uso terapêutico , Estrogênios , Feminino , Fluoresceínas/uso terapêutico , Hipuratos , Humanos , Imunoglobulina A/uso terapêutico , Interleucina-6/uso terapêutico , Isotiocianatos/uso terapêutico , Manose/uso terapêutico , Metenamina/análogos & derivados , Metenamina/uso terapêutico , Camundongos , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle
5.
BMJ ; 376: e068229, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264408

RESUMO

OBJECTIVE: To test and compare the efficacy of methenamine hippurate for prevention of recurrent urinary tract infections with the current standard prophylaxis of daily low dose antibiotics. DESIGN: Multicentre, open label, randomised, non-inferiority trial. SETTING: Eight centres in the UK, recruiting from June 2016 to June 2018. PARTICIPANTS: Women aged ≥18 years with recurrent urinary tract infections, requiring prophylactic treatment. INTERVENTIONS: Random assignment (1:1, using permuted blocks of variable length via a web based system) to receive antibiotic prophylaxis or methenamine hippurate for 12 months. Treatment allocation was not masked and crossover between arms was allowed. MAIN OUTCOME MEASURE: Absolute difference in incidence of symptomatic, antibiotic treated, urinary tract infections during treatment. A patient and public involvement group predefined the non-inferiority margin as one episode of urinary tract infection per person year. Analyses performed in a modified intention-to-treat population comprised all participants observed for at least six months. RESULTS: Participants were randomly assigned to antibiotic prophylaxis (n=120) or methenamine hippurate (n=120). The modified intention-to-treat analysis comprised 205 (85%) participants (antibiotics, n=102 (85%); methenamine hippurate, n=103 (86%)). Incidence of antibiotic treated urinary tract infections during the 12 month treatment period was 0.89 episodes per person year (95% confidence interval 0.65 to 1.12) in the antibiotics group and 1.38 (1.05 to 1.72) in the methenamine hippurate group, with an absolute difference of 0.49 (90% confidence interval 0.15 to 0.84) confirming non-inferiority. Adverse reactions were reported by 34/142 (24%) in the antibiotic group and 35/127 (28%) in the methenamine group and most reactions were mild. CONCLUSION: Non-antibiotic prophylactic treatment with methenamine hippurate might be appropriate for women with a history of recurrent episodes of urinary tract infections, informed by patient preferences and antibiotic stewardship initiatives, given the demonstration of non-inferiority to daily antibiotic prophylaxis seen in this trial. TRIAL REGISTRATION: ISRCTN70219762.


Assuntos
Antibacterianos/administração & dosagem , Antibioticoprofilaxia , Hipuratos/administração & dosagem , Metenamina/análogos & derivados , Infecções Urinárias/prevenção & controle , Adolescente , Adulto , Feminino , Humanos , Metenamina/administração & dosagem , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Infecções Urinárias/microbiologia , Adulto Jovem
6.
Molecules ; 27(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35268649

RESUMO

Solid phase extraction (SPE) is regarded as the most effective purification method for complex matrix samples owing to its simplicity of operator, time-saving, high accuracy, and environmental friendliness. SPE technology is still affected by the high cost of commercial SPE columns and poor adsorption selectivity. Hence, the development of low-cost and highly selective adsorbents is quite challenging and demanding in SPE. In this study, a novel 3DG functionalized magnetic solid phase extraction materials was prepared based on "thiol-ene" click chemistry. The structure, morphology, thermal stability, and magnetic properties of the magnetic composites were studied by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM). Then the adsorption performance of composite was determined by static adsorption experiments, which showed fast binding kinetics (100 min) and good adsorption performance (Qe = 65.34 mg/g). Moreover, these magnetic nanoparticles were used as adsorbents for magnetic solid phase extraction (MSPE) and coupled with high-performance liquid chromatography (HPLC) for separation and detection of illegally added hexamethylenetetramine in vermicelli. As for practical application, the recoveries for the spiked samples in the concentration range of 8-40 µg/g were between 83.24-92.69%, and the RSD was between 0.20-2.07%.


Assuntos
Metenamina
7.
Female Pelvic Med Reconstr Surg ; 28(3): e55-e61, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35272334

RESUMO

IMPORTANCE: There is little consensus on an effective nonantibiotic agent for the prevention of urinary tract infection (UTI) after pelvic reconstructive surgery. OBJECTIVE: The aim of the study was to investigate the impact of methenamine hippurate with cranberry capsules on rates of UTI after pelvic reconstructive surgery, among patients requiring short-term catheterization. STUDY DESIGN: In this randomized, double-blinded placebo-controlled trial, patients discharged with a catheter after pelvic reconstructive surgery were approached to participate. Participants were randomized to receive cranberry with methenamine or cranberry with placebo. Primary outcome was number of UTIs treated within 1 week after surgery. Secondary outcomes included incidence of UTIs treated within 6 weeks postoperatively, bacterial species on culture, urinary pH, catheter duration, patient adherence, and satisfaction. A sample size of 88 participants per arm was planned. RESULTS: From June 2019 to July 2021, 185 patients were randomized and 182 analyzed; 89 received placebo and 93 received methenamine. Both groups were similar. Incidence of UTI at 1 week was significantly higher in the placebo group (79.8%) compared with the methenamine group (66.7%; odds ratio, 1.97; 95% confidence interval, 1.01-3.87; P = 0.048). This difference increased by 6 weeks postoperatively (89.9% vs 72.0%; odds ratio, 3.45; 95% confidence interval, 1.51-7.87; P = 0.003). There were fewer pseudomonal UTIs in the methenamine group (P = 0.041). Duration of catheterization and urinary pH were similar. Overall adherence and level of satisfaction was high. CONCLUSIONS: In this high-risk population, methenamine was well tolerated and significantly reduced UTI rates. Methenamine with cranberry should be considered as an effective prophylactic therapy to reduce this common complication after pelvic surgery.


Assuntos
Infecções Urinárias , Vaccinium macrocarpon , Cápsulas/uso terapêutico , Cateteres , Feminino , Hipuratos , Humanos , Masculino , Metenamina/análogos & derivados , Metenamina/uso terapêutico , Infecções Urinárias/tratamento farmacológico
8.
Prog Transplant ; 32(1): 67-72, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34859711

RESUMO

INTRODUCTION: Recurrent urinary tract infections remain a challenge in solid organ transplant and have a negative impact on morbidity/mortality. PROJECT AIM: The purpose of this program evaluation was to determine the impact of methenamine on recurrent urinary tract infection in kidney and liver-kidney transplant recipients. DESIGN: This retrospective review included patients > 18 years of age who received a kidney or liver-kidney transplant. Patients were divided into the following groups: (1) Methenamine therapy initiation received methenamine for ≥ 180 days or (2) Non-methenamine therapy: did not receive recurrent urinary tract infection prophylaxis. A total of 60 patients were included. RESULTS: When comparing outcomes between methenamine therapy initiation and non-methenamine therapy group, a significant reduction in the rate of recurrent urinary tract infection was reported in the methenamine therapy initiation group (0.6 vs 1.3 per 180 patient days follow-up, P = 0.0005). A significant reduction was also noted with rate of asymptomatic bacteriuria, treatment failures, bacteremia, hospitalizations due to recurrent urinary tract infection, multi-drug resistant organism isolated, and the average duration of antibiotic use. A significant difference in the time to failure of methenamine therapy initiation versus non-methenamine therapy is noted up to 180 patient-days follow-up (RR 1.56, P = 0.0019). CONCLUSION: This evaluation supported methenamine therapy for recurrent urinary tract infection in kidney and liver-kidney transplant. The most significant impact of methenamine recurrent urinary tract infection was seen in the first 30 days after initiation.


Assuntos
Bacteriúria , Transplante de Rim , Infecções Urinárias , Feminino , Hipuratos/uso terapêutico , Humanos , Masculino , Metenamina/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle
10.
Int Urogynecol J ; 33(3): 571-580, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34115162

RESUMO

INTRODUCTION AND HYPOTHESIS: The objective was to find an alternative treatment to a low-dose antibiotic for the prevention of recurrent urinary tract infections (UTI) and to evaluate the difference in rates of reinfection within 1 year when treated with methenamine hippurate for prophylaxis compared with trimethoprim. METHODS: We present a non-blinded randomized trial comparing methenamine hippurate with trimethoprim for the prevention of recurrent UTI at 12 months after starting treatment. Women over 18 who had at least two culture-positive UTI in the prior 6 months or three in the prior year were included. Ninety-two patients met enrollment criteria and were randomized to receive daily prophylaxis with methenamine hippurate or trimethoprim for a minimum of 6 months. Both intent-to-treat and per-protocol analyses if patients received the alternative drug after randomization were analyzed using Student's t test, Mann-Whitney U test, Kaplan-Meier curves, log-rank test, and a logistic and multivariate regression model. The primary outcome of this study was culture-proven UTI recurrence by 12 months after initiating prophylaxis. RESULTS: In the intent-to-treat analysis, we found no difference between groups in recurrent UTI, with a 65% (28 out of 43) recurrence in the trimethoprim group versus 65% (28 out of 43) in the methenamine hippurate group (p = 1.00). In the per-protocol analysis, 65% (26 out of 40) versus 65% (30 out of 46) of patients had UTI recurrences in the trimethoprim group versus the methenamine hippurate group (p = 0.98). CONCLUSIONS: Methenamine hippurate may be an alternative for the prevention of recurrent UTI, with similar rates of recurrence and adverse effects to trimethoprim.


Assuntos
Trimetoprima , Infecções Urinárias , Feminino , Hipuratos/uso terapêutico , Humanos , Metenamina/análogos & derivados , Metenamina/uso terapêutico , Trimetoprima/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle
12.
Chem Commun (Camb) ; 57(61): 7581-7584, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34250986

RESUMO

A pharmacophore integration strategy was utilized to develop the first co-donor of formaldehyde and nitric oxide (FANO), composed of urotropine derived nitramine/nitrosamine. FANO simultaneously generated formaldehyde and nitric oxide on-demand, resulting in synergistic anticancer effects. Importantly, liposomal formulation of FANO effectively inhibited tumor growth with minimal side-effects, providing a potent combined nitric oxide therapy for malignancy.


Assuntos
Antineoplásicos/uso terapêutico , Formaldeído/metabolismo , Neoplasias/tratamento farmacológico , Doadores de Óxido Nítrico/uso terapêutico , Óxido Nítrico/metabolismo , Poliaminas/uso terapêutico , Animais , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Lipossomos/química , Metenamina/química , Camundongos , Doadores de Óxido Nítrico/síntese química , Nitrosaminas/síntese química , Nitrosaminas/uso terapêutico , Poliaminas/síntese química
13.
Br J Gen Pract ; 71(708): e528-e537, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34001538

RESUMO

BACKGROUND: Urinary tract infections (UTIs) are often treated with antibiotics and are a source of antibiotic overuse. AIM: To systematically review randomised controlled trials (RCTs) of adult women in the community with a history of recurrent UTIs and who use methenamine hippurate prophylactically. DESIGN AND SETTING: Systematic review of women in the UK, Australia, Norway, and US (aged ≥18 years) with recurrent UTIs receiving methenamine hippurate against placebo or no treatment, and antibiotics. METHOD: The authors searched three databases, clinical trial registries, and performed forward-backward citation analysis on references of included studies. RESULTS: Six studies involving 557 participants were included (447 were analysed). Of the six studies, five were published and one was an unpublished trial record with results, three compared methenamine hippurate against placebo or control, and three compared methenamine hippurate with antibiotics. For the number of patients who remained asymptomatic, methenamine hippurate showed a non-statistically significant trend of benefit versus antibiotics over 12 months (risk ratio [RR] 0.65, 95% confidence interval [CI] = 0.40 to 1.07, I 2 49%), versus control over 6 or 12 months (RR 0.56, 95% CI = 0.13 to 2.35, I 2 93%), and a non-statistically significant trend versus any antibiotic for abacteruria (RR 0.80, 95% CI = 0.62 to 1.03, I 2 23%). A similar non-statistically significant trend of benefits for methenamine hippurate for the number of UTI or bacteriuric episodes was found, and a non-statistically significant difference in the number of patients experiencing adverse events between methenamine hippurate and any comparator, with a trend towards benefit for the methenamine hippurate, was identified. Antibiotic use and resistance were not consistently reported. CONCLUSION: There is insufficient evidence to be certain of the benefits of methenamine hippurate to prevent UTI. Further research is needed to test the drug's effectiveness in preventing UTIs and as an alternative for antibiotic treatment for UTI.


Assuntos
Preparações Farmacêuticas , Infecções Urinárias , Adolescente , Adulto , Antibacterianos/uso terapêutico , Feminino , Hipuratos , Humanos , Metenamina/análogos & derivados , Metenamina/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle
14.
J Biotechnol ; 323: 331-340, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32950562

RESUMO

Suspensions of pea protein enriched flour (PP) inoculated with Lactobacillus plantarum NRRL B-4496 and uninoculated PP suspensions were incubated in vials covered with airtight caps. Organic compound compositions of fermented and unfermented PP suspensions (F-PP and U-PP, respectively) were analyzed using solid phase microextraction (SPME) coupled with gas chromatography - mass-spectrometry (GCMS). Acetic acid was detected in all samples; pH dropped from pH 6.5 to pH 4.1 in L. plantarum F-PP and to pH 5.3 in uninoculated F-PP. Abundance of acetic acid and minuscule presence of lactic acid in L. plantarum F-PP suggested that fermentation proceeded preferentially via the pyruvate formate lyase (PFL) pathway. Nonetheless, glycerol appeared to be the most abundant compound in L. plantarum F-PP samples; colorimetric analysis indicated that its average concentration in these samples was 1.05 g/L. A metabolic switch from the PFL pathway to glycerol production might occur due to acidity tolerance limitations of L. plantarum, glycerol production being associated with the release of phosphate, which can act as a buffer. Fermentation of PP by L. plantarum also led to formation of hexamine, which is a known food preservation agent. Presence of naturally formed hexamine and glycerol in food products may render using chemical additives needless.


Assuntos
Fermentação , Farinha , Glicerol/metabolismo , Lactobacillus plantarum/metabolismo , Metenamina/metabolismo , Proteínas de Ervilha/metabolismo , Ácido Acético/metabolismo , Anti-Infecciosos/farmacologia , Butiratos/metabolismo , Microbiologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Ácido Láctico/metabolismo , Lactobacillus plantarum/genética , Lipase , Metenamina/farmacologia , Microbiota
15.
J Cutan Pathol ; 47(11): 1096-1102, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32515092

RESUMO

The American Society of Dermatopathology has established an Appropriate Use Criteria (AUC) Committee with the intention of establishing evidence-based recommendations regarding the appropriateness of various ancillary tests commonly utilized by dermatopathologists. Periodic acid Schiff (PAS) and Grocott (or Gomori) methenamine silver (GMS) stains represent some of the most commonly employed ancillary tests in dermatopathology. The utility of these tests was targeted for evaluation by the AUC. This literature review represents a comprehensive evaluation of available evidence for the utility of PAS and/or GMS staining of skin and nail biopsies. In concert with expert opinion, these data will be incorporated into future recommendations by the AUC for PAS and GMS staining in routine dermatopathology practice.


Assuntos
Dermatologia/métodos , Metenamina , Patologia/métodos , Reação do Ácido Periódico de Schiff/métodos , Dermatopatias/diagnóstico , Coloração e Rotulagem/métodos , Humanos
16.
Astrobiology ; 20(5): 601-616, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32105506

RESUMO

Numerous laboratory studies of astrophysical ice analogues have shown that their exposure to ionizing radiation leads to the production of large numbers of new, more complex compounds, many of which are of astrobiological interest. We show here that the irradiation of astrophysical ice analogues containing H2O, CH3OH, CO, and NH3 yields quantities of hexamethylenetetramine-methanol (hereafter HMT-methanol; C7N4H14O) that are easily detectible in the resulting organic residues. This molecule differs from simple HMT, which is known to be abundant in similar ice photolysis residues, by the replacement of a peripheral H atom with a CH2OH group. As with HMT, HMT-methanol is likely to be an amino acid precursor. HMT has tetrahedral (Td) symmetry, whereas HMT-methanol has C1 symmetry. We report the computed expected infrared spectra for HMT and HMT-methanol obtained using ab initio quantum chemistry methods and show that there is a good match between the observed and computed spectra for regular HMT. Since HMT-methanol lacks the high symmetry of HMT, it produces rotational transitions that could be observed at longer wavelengths, although establishing the exact positions of these transitions may be challenging. It is likely that HMT-methanol represents an abundant member of a larger family of functionalized HMT molecules that may be present in cold astrophysical environments.


Assuntos
Exobiologia , Meio Ambiente Extraterreno , Metanol/análise , Metenamina/análise , Metenamina/química , Vibração
19.
Ann Pharmacother ; 54(4): 359-363, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31694390

RESUMO

Background: Methenamine is a drug used for the prevention of lower urinary tract infections (UTIs). However, efficacy has not been established in older adults or patients with varying degrees of kidney function. Objective: To evaluate the effectiveness of methenamine for the prevention of UTI in adults 60 years and older. Methods: This was a retrospective, pre-post, observational study. The study included primary care patients 60 years and older who were taking methenamine between January 1, 2015, and September 30, 2018. The primary outcome was the time to first UTI after methenamine initiation compared with the average time between UTIs in the 12 months prior to methenamine initiation. Results: Of 434 patients reviewed, 150 met inclusion criteria. The average time to UTI was 3.3 months prior to methenamine initiation compared with 5.5 months after methenamine initiation (P = 0.0004). There were 33 patients (22%) who did not have a UTI after methenamine initiation. Also, 14 patients (9.3%) had a calculated CrCl <30 mL/min at baseline. The average time to UTI in these patients was 3.3 months prior to methenamine initiation compared with 12.7 months after initiation (P < 0.0001). Conclusion and Relevance: Methenamine use was associated with a longer time to UTI in older adults with varying degrees of kidney function. The effectiveness of methenamine appeared to be similar regardless of kidney function, which is new evidence. Because of a lack of acquired resistance, methenamine may be an effective option for UTI prophylaxis in older adults.


Assuntos
Anti-Infecciosos Urinários/uso terapêutico , Metenamina/uso terapêutico , Infecções Urinárias/prevenção & controle , Idoso , Feminino , Humanos , Testes de Função Renal , Masculino , Estudos Retrospectivos , Resultado do Tratamento
20.
Dermatol Online J ; 25(4)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31046914

RESUMO

Slime has become extremely popular as a children's toy in recent years and is typically made with various household substances. Although reports of slime causing skin irritation are not uncommon, case reports of slime-induced allergic contact dermatitis have only recently surfaced. We present a case of a child with hand dermatitis, history of exposure to slime, and positive allergen patch testing to two ingredients found in slime. The case underscores the need for clinicians to be aware of slime as a possible cause of allergic contact dermatitis in children. Given the trend of newly-reported cases, we briefly review the current literature to date.


Assuntos
Dermatite Alérgica de Contato/etiologia , Dermatoses da Mão/induzido quimicamente , Jogos e Brinquedos , Criança , Feminino , Humanos , Metenamina/efeitos adversos , Metenamina/análogos & derivados , Testes do Emplastro , Tiazóis/efeitos adversos
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