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1.
Clin Exp Immunol ; 195(1): 1-9, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30307604

RESUMO

The objective of this study was to test the capacity of a newly developed fusion protein of interleukin 4 (IL-4) and IL-10 [IL4-10 fusion protein (FP)] to shift multiple pro-inflammatory pathways towards immune regulation, and to inhibit pro-inflammatory activity in arthritis models. The effects of IL4-10 FP in comparison with IL-4, IL-10 and IL-4 plus IL-10 on pro- and anti-inflammatory mediators, T cells and immunoglobulin (Ig) receptors in favour of immunoregulatory activity were studied. In addition, the capacity of IL4-10 FP to inhibit pro-inflammatory activity in ex-vivo and in-vivo arthritis models was investigated. IL4-10 FP robustly inhibited pro-inflammatory cytokine [IL-1ß, tumour necrosis factor (TNF)-α, IL-6 and IL-8] production in whole blood cultures, mediated by both the IL-10 and the IL-4 moiety. IL4-10 fusion protein induced IL-1 receptor antagonist (IL-1RA) production and preserved soluble TNF receptor (sTNFR) levels, strongly increasing IL-1RA/IL-1ß and sTNFR/TNF-α ratios. In addition, IL4-10 FP strongly inhibited T helper (Th) type 1 and 17 cytokine secretion, while maintaining FoxP3 expression and up-regulating Th2 activity. In addition, while largely leaving expression of activating Fc gamma receptor (FcγR)I, III and Fc epsilon receptor (FcεR) unaffected, it significantly shifted the FcγRIIa/FcγRIIb ratio in favour of the inhibitory FcγRIIb. Moreover, IL4-10 FP robustly inhibited secretion of pro-inflammatory cytokines by rheumatoid arthritis synovial tissue and suppressed experimental arthritis in mice, without inducing B cell hyperactivity. IL4-10 fusion protein is a novel drug, signalling cells to induce immunoregulatory activity that overcomes limitations of IL-4 and IL-10 stand-alone therapy, and therefore has therapeutic potential for inflammatory diseases such as rheumatoid arthritis.


Assuntos
Artrite Reumatoide/terapia , Imunoterapia/métodos , Inflamação/terapia , Interleucina-10/imunologia , Interleucina-4/uso terapêutico , Leucócitos Mononucleares/imunologia , Proteínas Recombinantes de Fusão/uso terapêutico , Animais , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/imunologia , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Imunomodulação , Inflamação/imunologia , Interleucina-4/genética , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteoglicanas , Proteínas Recombinantes de Fusão/genética , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia
2.
Andrologia ; 49(2)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27135437

RESUMO

The prevalence of testosterone substitution as well as of androgen deprivation therapy in men is increasing. This review aims to summarise available knowledge of the effects of sex steroids on cardiac structure and function in men. MEDLINE was searched through PubMed. Original studies, systematic reviews and meta-analyses, and relevant citations were screened. A short-term hormonal intervention study in healthy young men with respect to echocardiographic parameters of structure and function was performed. Preclinical research provides sufficient evidence for the heart as a substrate for sex hormones. In animals, administration of oestradiol appears to have beneficial effects on cardiac structure and function, whereas administration of testosterone to noncastrated animals adversely affects cardiac function. However, the effects of sex steroids on cardiac function and structure appear more heterogeneous in human observational studies while comparative, prospective studies in humans are lacking. It is concluded that although effects of testosterone substitution as well as of androgen deprivation on cardiac structure and function can be expected based on pre-clinical research, there exists an important knowledge gap of the effects of hormonal intervention in men. As such, there is a need to address this question in future prospective intervention trials.


Assuntos
Androgênios/deficiência , Coração/efeitos dos fármacos , Terapia de Reposição Hormonal , Miocárdio/metabolismo , Testosterona , Função Ventricular/efeitos dos fármacos , Adulto , Fatores Etários , Animais , Inibidores da Aromatase/administração & dosagem , Inibidores da Aromatase/farmacologia , Ecocardiografia , Estradiol/administração & dosagem , Estradiol/farmacologia , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Feminino , Coração/diagnóstico por imagem , Coração/fisiopatologia , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Hipogonadismo/fisiopatologia , Letrozol , Masculino , Miocárdio/patologia , Nitrilas/administração & dosagem , Nitrilas/farmacologia , Fatores Sexuais , Testosterona/efeitos adversos , Testosterona/uso terapêutico , Triazóis/administração & dosagem , Triazóis/farmacologia , Ultrassonografia Doppler
3.
Ocul Immunol Inflamm ; 31(4): 710-716, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35404742

RESUMO

PURPOSE: To report uveitis' spectrum in a private practice cohort in the city of Buenos Aires, Argentina. METHODS: Retrospective review at Instituto de la Visión (November 2011-October 2015). Standard demographics, ethnicity and Native American aboriginal ancestry were recorded. RESULTS: Among 212 patients, median age 45 (6-97), 10% pediatric, 35% bilateral, 72% non-idiopathic, 36% infectious. Anterior uveitis presented in 50%, followed by posterior (32%), intermediate (9%) and panuveitis (8%). Frequent visits (≥ 6 per year) needed by 29%: posterior, non-idiopathic disease with 79% systemic immunosuppression requirement was their main presentation. Native American aboriginal ancestry was reported by 22.64% of the whole cohort and 37% of frequent visits' subgroup. CONCLUSIONS: Unilateral, non-idiopathic, non-infectious anterior uveitis was the most frequent presentation, in agreement with reports coming from western developed cities. The multi-racial Argentinian population with specific Native American aboriginal ancestry might contribute to certain forms of posterior uveitis and their response to treatment.


Assuntos
Uveíte Anterior , Uveíte , Humanos , Criança , Pessoa de Meia-Idade , Argentina/epidemiologia , Atenção Terciária à Saúde , Uveíte/diagnóstico , Uveíte/epidemiologia , Centros de Atenção Terciária , Uveíte Anterior/epidemiologia , Encaminhamento e Consulta , Estudos Retrospectivos
4.
Magn Reson Med ; 67(2): 457-63, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22052363

RESUMO

A method is presented which allows precise temperature and longitudinal (T(1)) relaxation time measurements with high spatial and temporal resolution. This is achieved by combining dynamic variable flip angle based T(1) relaxation mapping with proton resonance frequency shift based thermometry. Herein, dynamic T(1) mapping is either used as a complementary measure of temperature or for the detection of T(1) contrast agent release. For the first application, the temperature evolution during a high-intensity focused ultrasound tissue ablation experiment was measured in both, porcine fat and muscle, simultaneously. In this application, temperature accuracies of 2.5 K for T(1)-based thermometry in fat and 1.2 K for proton resonance frequency shift-based thermometry in muscle were observed. The second application relates to MR-guidance of high-intensity focused ultrasound-induced local drug delivery by means of thermo-sensitive liposomes labeled with a T(1) contrast agent (Gd-HPDO3A). When the measured temperature exceeded the phase transition temperature of the liposomes, T(1) was observed to decrease with a good temporal and spatial correlation due to the release of Gd-HPDO3A. The presented results demonstrate the feasibility of the proposed method for two important applications in MR-guided noninvasive therapy. It offers a high temporal resolution when compared with interleaved Look-Locker based T(1) mapping techniques and thus represents an interesting candidate for simultaneous real-time monitoring of T(1) and temperature changes.


Assuntos
Algoritmos , Sistemas de Liberação de Medicamentos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Imageamento por Ressonância Magnética/métodos , Termômetros , Procedimentos Cirúrgicos Ultrassônicos , Animais , Meios de Contraste , Estudos de Viabilidade , Gadolínio , Compostos Heterocíclicos , Lipossomos , Compostos Organometálicos , Imagens de Fantasmas , Suínos
5.
Acta Gastroenterol Belg ; 85(3): 537-539, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36198300

RESUMO

Question: A 62-year old man presented to our tertiary care hospital for a second opinion regarding end stage COPD GOLD 4D. He had a medical history of former alcohol use complicated by liver steatosis and former smoking. Upon admission the patient complained of constipation and abdominal distension. Physical examination showed diffuse hypertympanic percussion and diffuse abdominal pain upon palpation without signs of peritoneal irrita- tion. CRP, hemoglobin, lactate, liver enzymes, and serum creatinine were within limits of normal. Abdominal radiography showed dilatation of the colon transversum with intramural and intra-abdominal free air (Figure 1). Contrast-enhanced abdominal CT showed extensive intramural air in the right hemicolon (Figure 2). Answer: The findings are consistent with pneumatosis intestinalis (PI). Conservative management with oxygen, triple bronchodilator therapy, fasting, laxation and antibiotic therapy resulted in resolution of the clinical symptoms.


Assuntos
Pneumatose Cistoide Intestinal , Doença Pulmonar Obstrutiva Crônica , Antibacterianos/uso terapêutico , Broncodilatadores , Constipação Intestinal/etiologia , Creatinina , Humanos , Lactatos , Masculino , Pessoa de Meia-Idade , Oxigênio , Pneumatose Cistoide Intestinal/complicações , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico
6.
ESC Heart Fail ; 9(6): 4315-4324, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36043434

RESUMO

Multisystem Inflammatory Syndrome in Adult (MIS-A) is a rare COVID-19 complication, presenting as fever with laboratory evidence of inflammation, severe illness requiring hospitalization and multisystem organ involvement. We report on a 25-year-old man presenting with fever, rash, abdominal pain, diarrhoea and vomiting following prior asymptomatic COVID-19 infection. He developed refractory shock and type 1 respiratory insufficiency requiring mechanical ventilation. Diagnostic testing revealed significant inflammation, anemia, thrombocytopenia, acute kidney injury, hepatosplenomegaly, colitis, lymphadenopathy and myocarditis necessitating inotropy. Ventilatory, vasopressor and inotropic support was weaned following pulse corticosteroids and intravenous immunoglobulins. Heart failure therapy was started. Short-term follow-up shows resolution of inflammation and cardiac dysfunction.


Assuntos
COVID-19 , Miocardite , Masculino , Humanos , Adulto , COVID-19/complicações , COVID-19/diagnóstico , SARS-CoV-2 , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Miocardite/complicações , Miocardite/diagnóstico , Inflamação , Cardiotônicos
7.
Radiother Oncol ; 173: 188-196, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35661677

RESUMO

Surface guidance systems enable patient positioning and motion monitoring without using ionising radiation. Surface Guided Radiation Therapy (SGRT) has therefore been widely adopted in radiation therapy in recent years, but guidelines on workflows and specific quality assurance (QA) are lacking. This ESTRO-ACROP guideline aims to give recommendations concerning SGRT roles and responsibilities and highlights common challenges and potential errors. Comprehensive guidelines for procurement, acceptance, commissioning, and QA of SGRT systems installed on computed tomography (CT) simulators, C-arm linacs, closed-bore linacs, and particle therapy treatment systems are presented that will help move to a consensus among SGRT users and facilitate a safe and efficient implementation and clinical application of SGRT.


Assuntos
Radioterapia Guiada por Imagem , Humanos , Aceleradores de Partículas , Posicionamento do Paciente , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X/métodos
8.
Int J Retina Vitreous ; 8(1): 33, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672810

RESUMO

Tertiary outpatient ophthalmology clinics are high-risk environments for COVID-19 transmission, especially retina clinics, where regular follow-up is needed for elderly patients with multiple comorbidities. Intravitreal injection therapy (IVT) for chronic macular diseases, is one of the most common procedures performed, associated with a significant burden of care because of the vigorous treatment regimen associated with multiple investigations. While minimizing the risk of COVID-19 infection transmission is a priority, this must be balanced against the continued provision of sight-saving ophthalmic care to patients at risk of permanent vision loss. This review aims to give evidence-based guidelines on managing IVT during the COVID-19 pandemic in common macular diseases such as age-related macular degeneration, diabetic macula edema and retinal vascular disease and to report on how the COVID-19 pandemic has affected IVT practices worldwide.To illustrate some real-world examples, 18 participants in the International Retina Collaborative, from 15 countries and across four continents, were surveyed regarding pre- and during- COVID-19 pandemic IVT practices in tertiary ophthalmic centers. The majority of centers reported a reduction in the number of appointments to reduce the risk of the spread of COVID-19 with varying changes to their IVT regimen to treat various macula diseases. Due to the constantly evolving nature of the COVID-19 pandemic, and the uncertainty about the normal resumption of health services, we suggest that new solutions for eye healthcare provision, like telemedicine, may be adopted in the future when we consider new long-term adaptations required to cope with the COVID-19 pandemic.

9.
Colorectal Dis ; 13(12): 1432-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20958916

RESUMO

AIM: The aim of this pilot study was to determine whether the type of approach (open or laparoscopic) and the order of devascularization during laparoscopic colectomy affect intestinal barrier function, local inflammatory response and clinical outcome. METHOD: Twenty-two patients undergoing elective colectomy from April 2006 to July 2008 were randomized to two sequences of vascular ligation, starting with either the inferior mesenteric artery or the ileocolic artery. Eighteen patients scheduled for open surgery served as a prospective control group. To assess the intestinal barrier function, release of intestinal fatty-acid binding protein (I-FABP; a marker of mucosal injury and ischaemia) was measured pre- and postoperatively. Mesenteric lymph nodes were harvested to assess the expression of inflammatory mediator-related genes using multiplex ligation probe amplification. The study was registered under NTR1025. RESULTS: Laparoscopic devascularization starting at the ileocolic artery resulted in a significantly increased excretion of I-FABP over time (P = 0.002). In this group, the I-FABP levels were significantly increased on postoperative days 1 and 3 compared with preoperative values (P = 0.011 and P = 0.001, respectively). There were no differences in expression of inflammatory mediator-related genes or postoperative morbidity among the groups. CONCLUSIONS: In this pilot study, devascularization commencing at the ileocolic artery during laparoscopic colectomy was associated with prolonged intestinal mucosal ischaemia.


Assuntos
Artérias/cirurgia , Colectomia/métodos , Colo/fisiologia , Proteínas de Ligação a Ácido Graxo/urina , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/fisiologia , RNA Mensageiro/metabolismo , Adulto , Idoso , Análise de Variância , Colo/imunologia , Colo/cirurgia , Doenças do Colo/cirurgia , Feminino , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/cirurgia , Laparoscopia/efeitos adversos , Ligadura/efeitos adversos , Ligadura/métodos , Linfonodos/metabolismo , Masculino , Artérias Mesentéricas/cirurgia , Pessoa de Meia-Idade , Projetos Piloto , Estatísticas não Paramétricas , Adulto Jovem
10.
J Fr Ophtalmol ; 43(9): 929-943, 2020 Nov.
Artigo em Francês | MEDLINE | ID: mdl-32778347

RESUMO

Phacoemulsification is the most frequently performed surgery in the world. Over the past few years, this surgery seems to have reached a plateau with no further innovative breakthroughs. In this paper, we focus on alternatives techniques, the latest innovations, and the research and development pipeline in this field.


Assuntos
Extração de Catarata , Catarata , Terapia a Laser , Cristalino , Oftalmologia , Facoemulsificação , Catarata/diagnóstico , Catarata/epidemiologia , Humanos
11.
J Psychopharmacol ; 22(1): 24-32, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18187530

RESUMO

The use of non-selective gamma-aminobutyric acid (GABA) enhancers, such as benzodiazepines in the treatment of anxiety disorders is still widespread but hampered by unfavourable side effects. some of these may be associated with binding properties to certain subtypes of the GABA(A) receptor that are unnecessary for therapeutic effects. MK-0343 was designed to be a less sedating anxiolytic, based on reduced efficacy at the alpha1 subtype and significant efficacy at alpha2 and alpha3 subtypes of the GABA(A) receptor. This paper is a double-blind, four-way cross-over (n = 12) study to investigate the effects of MK-0343 (0.25 and 0.75 mg) in comparison to placebo and an anxiolytic dose (2 mg) of the non-selective agonist lorazepam. Effects were measured by eye movements, body sway, Visual Analogue scales (VAS) and memory tests. Lorazepam impaired saccadic peak velocity (SPV), VAs alertness scores, postural stability and memory and increased saccadic latency and inaccuracy. MK-0343 0.75 mg was equipotent with lorazepam as indicated by SPV (-42.4 deg/s), saccadic latency (0.02 s) and VAS alertness scores (1.50 ln mm), while effects on memory and postural stability were smaller. MK-0343 0.25 mg only affected postural stability to a similar extent as MK-0343 0.75 mg. The effect profile of MK-0343 0.75 mg is different from the full agonist lorazepam, which could reflect the selective actions of this compound. Although less effect on VAS alertness was expected, diminished effects on memory and postural stability were present. Clinical studies in anxiety patients should show whether this dose of MK-0343 is therapeutically effective with a different side-effect profile.


Assuntos
Ansiolíticos/farmacologia , Agonistas de Receptores de GABA-A , Lorazepam/farmacologia , Adolescente , Adulto , Ansiolíticos/farmacocinética , Cognição/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Medição da Dor , Piridazinas/farmacologia , Movimentos Sacádicos/efeitos dos fármacos , Triazóis/farmacologia
12.
J Chromatogr Sci ; 46(9): 793-803, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19007481

RESUMO

Orthogonal or dissimilar separation systems provide different selectivities and their application can facilitate the development of methods to identify and quantify impurities in a drug substance. Two sets of chromatographic systems potentially applicable for method development were evaluated using four drug/impurity profiles. The sets consist of orthogonal or dissimilar systems and systems with good overall separation properties, selected in earlier studies. The aim of this study is to evaluate these systems for selectivity differences in the impurity profiles. These differences should allow determining the number of compounds occurring in an impurity profile. Then, one or a very limited number of systems is to be proposed for further method development. To examine the selectivity changes and separation quality for each impurity profile, both the normalized retention times tau and the resolutions between pairs of consecutively eluting peaks were plotted on parallel axes, representing the systems. For each profile, several systems of the studied sets can serve as potential starting points for further method development. All impurities could be separated from the active substance and from each other on at least one system. However, for the different profiles, different systems were selected as best, which makes that each system in a given set has its importance, depending on the properties of the profile.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Preparações Farmacêuticas/análise
13.
Br J Radiol ; 91(1083): 20170714, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29212356

RESUMO

OBJECTIVE: The purpose of this study was to correlate the total dysphagia risk score (TDRS) with swallowing function as measured by videofluoroscopy of swallowing using the swallowing performance scale (SPS) and the penetration aspiration scale (PAS). METHODS: 63 patients from two different centres treated with radiotherapy for head and neck cancer were evaluated in the current study. Swallowing videofluoroscopies at baseline, 6 and 12 months following radiotherapy were evaluated by two observers. The TDRS of all patients was calculated and correlated with the consensus PAS and SPS scores of the two observers. RESULTS: Regarding the PAS scale, we did not observe a significant correlation with the TDRS. Regarding SPS, we found a significant correlation at 6 months (p = 0.01) and a borderline significant correlation at 12 months (p = 0.05). We observed statistically lower SPS scores for patients in the intermediate-risk category when compared to the high-risk category. When we compared low vs high TDRS risk patients, we did not observe a significant difference regarding SPS scores. When comparing low- vs intermediate-risk patients, we observed higher SPS scores in the low-risk group (p = 0.01). When the low- and intermediate-risk patients were grouped together, we observed less swallowing problems as measured by SPS in the low and intermediate group when compared to the high-risk group (p = 0.05) at 6 months. CONCLUSION: Patients with high-risk TDRS scores have higher SPS scores when compared to the intermediate group and the intermediate- and low-risk group together. However, low-risk patients in our patient cohort could not be distinguished from high or intermediate-risk patients. Advances in knowledge: TDRS was never correlated with videofluoroscopies in past studies. The hypothesis of this paper was to see if the TDRS could guide us to see which patients are at risk for high scores on SPS and PAS and might need a videofluoroscopic examination in the follow up. Given the poor correlations in our study, however, we cannot recommend the use of the TDRS to select patients who might benefit from the additional information provided by videofluoroscopies.


Assuntos
Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Fluoroscopia , Neoplasias de Cabeça e Pescoço/radioterapia , Gravação em Vídeo , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
14.
Nat Biomed Eng ; 2: 649-656, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-30263872

RESUMO

Microsurgery of the retina would be dramatically improved by instruments that offer supra-human precision. Here, we report the results of a first-in-human study of remotely controlled robot-assisted retinal surgery performed through a telemanipulation device. Specifically, 12 patients requiring dissection of the epiretinal or inner limiting membrane over the macula were randomly assigned to either undergo robot-assisted-surgery or manual surgery, under general anaesthesia. We evaluated surgical success, duration of surgery and amount of retinal microtrauma as a proxy for safety. Surgical outcomes were equally successful in the robotic-surgery and manual-surgery groups. Differences in the amount of retinal microtrauma between the two groups were statistically insignificant, yet dissection took longer with robotic surgery (median time, 4 min 5 s) than with manual surgery (1 min 20 s). We also show the feasibility of using the robot to inject recombinant tissue plasminogen activator under the retina to displace sight-threatening haemorrhage in three patients under local anaesthesia. A safe and viable robotic system for intraocular surgery would enable precise and minimally traumatic delivery of gene therapy or cell therapy to the retina.

15.
J Psychopharmacol ; 21(4): 374-83, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17092968

RESUMO

TPA023, a GABA(A) alpha2,3 alphasubtype-selective partial agonist, is expected to have comparable anxiolytic efficacy as benzodiazepines with reduced sedating effects. The compound lacks efficacy at the alpha1 subtype, which is believed to mediate these effects. This study investigated the effects of 0.5 and 1.5 mg TPA023 and compared them with placebo and lorazepam 2 mg (therapeutic anxiolytic dose). Twelve healthy male volunteers participated in this placebo-controlled, double-blind, double-dummy, four-way, cross-over study. Saccadic eye movements and visual analogue scales (VAS) were used to assess the sedative properties of TPA023. The effects on posturaL stability and cognition were assessed using body sway and a standardized battery of neurophysiological memory tests. Lorazepam caused a significant reduction in saccadic peak velocity, the VAS alertness score and impairment of memory and body sway. TPA023 had significant dose dependent effects on saccadic peak velocity (85 deg/sec maximum reduction at the higher dose) that approximated the effects of lorazepam. In contrast to lorazepam, TPA023 had no detectabLe effects on saccadic latency or inaccuracy. Also unlike lorazepam, TPA023 did not affect VAS alertness, memory or body sway. These results show that the effect profile of TPA023 differs markedly from that of lorazepam, at doses that were equipotent with regard to effects on saccadic peak veLocity. Contrary to lorazepam, TPA023 caused no detectable memory impairment or postural imbalance. These differences reflect the selectivity of TPA023 for different GABA(A) receptor subtypes.


Assuntos
Ansiolíticos/farmacologia , Agonistas de Receptores de GABA-A , Lorazepam/farmacologia , Piridazinas/farmacologia , Triazóis/farmacologia , Adulto , Ansiolíticos/efeitos adversos , Ansiolíticos/farmacocinética , Área Sob a Curva , Pressão Sanguínea/efeitos dos fármacos , Cognição/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Eletrocardiografia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Lorazepam/efeitos adversos , Lorazepam/farmacocinética , Masculino , Postura , Piridazinas/administração & dosagem , Piridazinas/efeitos adversos , Piridazinas/farmacocinética , Movimentos Sacádicos/efeitos dos fármacos , Triazóis/administração & dosagem , Triazóis/efeitos adversos , Triazóis/farmacocinética
16.
Br J Ophthalmol ; 90(10): 1259-62, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16980644

RESUMO

BACKGROUND: As optical coherence tomography (OCT) is widely used for diagnosis and monitoring of ocular pathology, especially in the elderly people, the influence of cataract on image quality and macular retinal thickness was studied. METHODS: In 29 patients scheduled for cataract surgery, preoperative and postoperative OCT scans were obtained. Cataracts were categorised as nuclear, posterior or cortical. Parameters for image quality (signal-to-noise ratio (SNR)) and signal strength and macular thickness were compared. A three-level expert grading scale was used to evaluate the discriminative abilities of SNR and signal strength. RESULTS: Nuclear cataracts (n = 12) provided better preoperative scans (higher SNR/signal strength) than posterior (n = 7) and cortical (n = 10) cataracts (p<0.004). Postoperatively SNR and signal strength increased significantly in all patients (p<0.001). The SNR was better at discriminating poor from acceptable and good scans than signal strength (area under the receiver operating curve: 0.879 and 0.810, respectively). Postoperative macular thickness overall showed a significant increase (p = 0.005), most evident in patients with posterior cataracts (p = 0.028). CONCLUSIONS: OCT imaging is influenced by cataract; image quality is reduced preoperatively and macular thickness measurements are slightly increased postoperatively. In individual patients, OCT scans remain reliable for gross clinical interpretation, even in the presence of cataract.


Assuntos
Catarata/patologia , Macula Lutea/patologia , Tomografia de Coerência Óptica , Idoso , Idoso de 80 Anos ou mais , Catarata/fisiopatologia , Extração de Catarata , Humanos , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Acuidade Visual
17.
J Pharm Biomed Anal ; 42(2): 155-70, 2006 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-16621413

RESUMO

The assay of a drug substance (DS) is one of the tests required to confirm the active pharmaceutical ingredient (API) quality at release. In the past, usually volumetric titration methods were performed, that were precise, but often non-specific. Nowadays specific chromatographic assay procedures are preferred. However, high performance liquid chromatographic (HPLC) methods, the way they are usually executed, tend to be less precise and have a larger total method variation compared to titration methods. The capabilities of fully validated titration and HPLC assay methods were determined and compared. It was studied which factors had the largest effects on the capability of chromatographic HPLC methods in order to improve their precision and precision-to-tolerance ratio. This was done using multiple Gage R&R (repeatability & reproducibility) studies and an experimental design approach. The investigations showed that it was feasible to define an HPLC method with a similar capability as the titration method. The most important factor determining the precision was demonstrated to be higher sample and reference material weights. When low weights are to be used, increasing the number of sample preparations and the number of reference solutions may enhance the method capability.


Assuntos
Cromatografia Líquida de Alta Pressão , Modelos Teóricos , Preparações Farmacêuticas/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Cromatografia Líquida de Alta Pressão/tendências , Estabilidade de Medicamentos , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Titulometria/métodos , Titulometria/normas , Titulometria/tendências
18.
J Pharm Biomed Anal ; 41(3): 751-60, 2006 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-16466886

RESUMO

The classification or characterization of stationary phases based on chromatographic parameters, in general, requires different test solutes/mixtures and several mobile phases. To simplify the classification/characterization of reversed-phase liquid chromatographic columns, to be used in separating drug/impurity profiles, a new test procedure was proposed. It consists of injecting two mixtures of relatively similar active substances applying a standard gradient. The aim was to evaluate from this approach the selectivity differences and overall separation quality of newly tested columns compared to that in an earlier selected set of eight stationary phases. The selectivity differences of the columns were evaluated by correlation coefficient-based weighted-average-linkage dendrograms and color maps. Derringer's desirability functions were used to rank similar stationary phases according to their overall separation quality. Four columns of 27 examined were, for instance, considered different from the earlier selected eight and could be added to the selection. A number of tested stationary phases might be considered as alternatives for some from the initial set. For three columns the newly tested stationary phases did not contain alternatives.


Assuntos
Preparações Farmacêuticas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas/métodos , Sensibilidade e Especificidade
20.
Biochim Biophys Acta ; 506(1): 64-80, 1978 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-413578

RESUMO

The effect of toluene on Escherichia coli has been examined. In the presence of Mg2+, toluene removes very little protein, phospholipid, or lipopolysacharide from E. coli. In the absence of Mg2+, or in the presence of EDTA, toluene removes considerably more cell material, including several specific cytoplasmic proteins such as malate dehydrogenase (EC 1.1.1.37). In contrast, glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and glutamate dehydrogenase (EC 1.4.1.4) are not released at all under the same conditions. Cells treated with toluene in the presence of Mg2+ remain relatively impermeable to pyridne nucleotides, while cells treated with toluene in the presence of EDTA become permeable to these compounds. Freeze-fracture electron microscopy shows that toluene causes considerable damage to the cytoplasmic membrane, while the outer membrane remains relatively intact. These results indicate that the permeability characteristics of toluene-treated cells depend at least partly on the state of the outer membrane after the toluene treatment.


Assuntos
Membrana Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Tolueno/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Citoplasma/metabolismo , Ácido Edético/farmacologia , Escherichia coli/metabolismo , Ácidos Graxos/metabolismo , Magnésio/farmacologia , Membranas/efeitos dos fármacos , Oxirredutases/metabolismo , Proteínas/metabolismo
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