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1.
Anaesth Intensive Care ; 46(4): 381-385, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29966111

RESUMO

Traditionally heparin has been the anticoagulant of choice for venous dialysis catheter locking. There is systemic leakage of heparin catheter locking solutions at the time of injection. Alternative agents, such as citrate, are increasingly being used. We are not aware of any data in the critical care literature on the effect of citrate locking of venous dialysis catheters on systemic ionised calcium (iCa2+). To assess the effect of 4% citrate locking of venous dialysis catheters on systemic iCa2+ in intensive care patients we performed a prospective observational study of 50 paired samples in 26 intensive care patients receiving 4% citrate dialysis catheter locking in an adult tertiary intensive care unit between May 2016 and December 2016. Arterial blood gas (ABG) analysis was performed prior to venous dialysis catheter locking and a baseline iCa2+ result obtained. The catheter was locked with 4% citrate solution. A further ABG was sampled between 30 and 120 seconds later and the iCa2+ results were compared. Patients were observed for clinical signs of hypocalcaemia. On average, there was little difference between the pre- and post-catheter locking iCa2+ (median pre-locking iCa2+ 1.19 mmol/l, mean change of +0.004 mmol/l, 95% confidence interval [CI] -0.004 to 0.013, P=0.34). There was no evidence this difference differed by length of catheter P=0.26) or site of catheter P=0.85) insertion, but there was some evidence that this differed by receipt of citrate dialysis circuit anticoagulation P=0.013). Patients who received citrate dialysis circuit anticoagulation had an increase in catheter locking iCa2+ by 0.017 mmol/l (95% CI 0.00 to 0.028). Locking of venous dialysis catheters with 4% citrate solution has no clinically significant effect on systemic iCa2+ in intensive care patients with indwelling venous dialysis catheters.


Assuntos
Anticoagulantes/farmacologia , Cálcio/metabolismo , Cateteres de Demora , Ácido Cítrico/farmacologia , Cuidados Críticos , Diálise Renal/instrumentação , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
2.
J Surg Oncol ; 117(3): 451-456, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29127699

RESUMO

BACKGROUND AND OBJECTIVES: This study evaluated the relationship between the maximum standardized uptake value (SUVmax) of preoperative positron emission tomography/computed tomography (PET/CT) and the characteristics of lung adenocarcinoma featuring ground-glass opacity nodules (GGN). METHODS: The association of the SUVmax of preoperative PET/CT with ground-glass opacity (GGO) proportion on CT, subtypes of adenocarcinoma (minimally invasive adenocarcinoma, invasive adenocarcinoma), predominant types of invasive adenocarcinoma, and size of the total and invasive components of pathology were evaluated in 190 patients who underwent resection for lung adenocarcinoma featuring GGN. RESULTS: The mean SUVmax of non-solid GGN and partly solid GGN were 0.53 and 1.32, respectively (P = 0.029). The mean SUVmax of the main masses in 38 patients with MIA and 152 with invasive adenocarcinoma were 0.86 and 1.36, respectively (P = 0.029). The mean SUVmax of acinar, lepidic, papillary, and solid tumors were 1.61, 0.87, 0.98, and 1.60, respectively. The mean SUVmax of invasive components measuring ≤10 mm, 11-20 mm, and >20 mm were 0.84, 1.66, and 2.09, respectively (P < 0.001). CONCLUSIONS: The SUVmax of lung adenocarcinoma featuring GGN can vary depending on the GGO proportion. A higher SUVmax can be expected in invasive adenocarcinoma than in MIA, and solid and acinar-predominant invasive adenocarcinoma showed a higher SUVmax.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adenocarcinoma de Pulmão , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Cuidados Pré-Operatórios/métodos , Compostos Radiofarmacêuticos/farmacocinética , Estudos Retrospectivos
3.
Anaesth Intensive Care ; 44(4): 474-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27456177

RESUMO

Heparin locking of venous dialysis catheters is routinely performed in intensive care to maintain catheter patency when the catheters are not being used. Leakage of heparin into the circulation can potentially cause systemic anticoagulation and may present a risk to intensive care patients. To assess the effect of 5000 units per millilitre heparin locking of non-tunnelled dialysis catheters on systemic anticoagulation, we performed a prospective observational study of ten intensive care patients receiving heparin locking of dialysis catheters in an adult tertiary intensive care unit between July and September 2015. Activated partial thromboplastin time (APTT) was measured prior to, and three minutes after, heparin locking of catheter lumens with the manufacturer's recommended locking volume to assess the effect on systemic anticoagulation. Heparin locking of venous dialysis catheters resulted in a significant rise in APTT (P=0.002). The median rise was by 56 seconds (interquartile range 30-166.5). Following heparin locking, 80% of patients had APTT values within or above the range associated with therapeutic anticoagulation. Heparin locking of non-tunnelled venous dialysis catheters can cause systemic anticoagulation in intensive care patients and therefore poses a potential risk to patient safety.


Assuntos
Anticoagulantes/uso terapêutico , Cuidados Críticos , Heparina/uso terapêutico , Diálise Renal/métodos , Adulto , Idoso , Catéteres , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Estudos Prospectivos
4.
Biopharm Drug Dispos ; 32(1): 38-49, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21162118

RESUMO

Hypertension is the most common comorbidity and major risk factor in patients with erectile dysfunction. The pharmacokinetics of mirodenafil, used for the treatment of erectile dysfunction, after the intravenous and oral administration (20 mg/kg) to 6-week-old rats (with blood pressure within the normotensive range) and 16-week-old spontaneously hypertensive rats (SHRs) and their age-matched control normotensive Kyoto-Wistar (KW) rats, and 16-week-old deoxycorticosterone acetate-salt-induced hypertensive rats (DOCA-salt rats) and their age-matched control Sprague-Dawley (SD) rats were compared. It was found that time-averaged renal clearance (Cl(r)) was of minor importance and that time-averaged non-renal clearance (Cl(nr)) was dominant. In both 6- and 16-week-old SHRs, the Cl(nr)s and areas under the curve (AUCs) of intravenous mirodenafil were significantly smaller and greater than those of the controls, but in 16-week-old DOCA-salt rats, they were comparable to the controls. Although the AUC of oral mirodenafil in 16-week-old SHRs was comparable to the controls, the Cl(nr)s (or total body clearances, Cls) of intravenous mirodenafil and intestinal intrinsic clearances were significantly smaller than the controls and comparable to the controls for both 6- and 16-week-old SHRs, unlike in the 16-week-old DOCA-salt rats. The above data suggest that the significantly smaller Cl(nr) and greater AUC of intravenous mirodenafil and comparable AUC of oral mirodenafil in 16-week-old SHR could be due to the hereditary characteristics of SHRs, and not due to the hypertensive state itself.


Assuntos
Desoxicorticosterona/toxicidade , Hipertensão/metabolismo , Pirimidinonas/farmacocinética , Sulfonamidas/farmacocinética , Animais , Modelos Animais de Doenças , Hipertensão/induzido quimicamente , Masculino , Pirimidinonas/metabolismo , Distribuição Aleatória , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ratos Sprague-Dawley , Sulfonamidas/metabolismo
5.
J Pharm Pharmacol ; 61(10): 1325-32, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19814864

RESUMO

OBJECTIVES: It has been reported that mirodenafil is primarily metabolized via hepatic cytochrome P450 (CYP) 1A1/2, 2B1/2, 2D1 and 3A1/2 in rats. It has also been reported that the protein expression of hepatic CYP3A1 and intestinal CYP1A1 and 3A1/2 increases and that of hepatic CYP2D1 decreases in rats with acute renal failure induced by uranyl nitrate (U-ARF rats). Thus, the pharmacokinetics of mirodenafil were studied in control and U-ARF rats. METHODS: The pharmacokinetic parameters of mirodenafil and SK3541 (a metabolite of mirodenafil) were compared after the intravenous and oral administration of mirodenafil at a dose of 20 mg/kg to U-ARF and control rats. KEY FINDINGS: After interavenous administration of mirodenafil to U-ARF rats, the total area under the concentration-time curve (AUC) of mirodenafil was significantly smaller (36.5% decrease) than controls, possibly due to the significantly faster non-renal clearance (66.1% increase; because of increase in the protein expression of hepatic CYP3A1) than controls. After the oral administration of mirodenafil to U-ARF rats, the AUC of mirodenafil was also significantly smaller (47.8% decrease) due to the increase in the protein expression of hepatic CYP3A1 and intestinal CYP1A1 and 3A1/2 compared with controls. CONCLUSIONS: After both intravenous and oral administration of mirodenafil to U-ARF rats, the AUC(SK3541)/AUC(mirodenafil) ratios were comparable with that in controls and this could be due to further metabolism of SK3541 in rats.


Assuntos
Injúria Renal Aguda/metabolismo , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Fígado/metabolismo , Pirimidinonas/farmacocinética , Sulfonamidas/farmacocinética , Injúria Renal Aguda/induzido quimicamente , Administração Oral , Animais , Citocromo P-450 CYP3A , Modelos Animais de Doenças , Injeções Intravenosas , Mucosa Intestinal/metabolismo , Masculino , Microssomos/metabolismo , Pirimidinonas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Sulfonamidas/administração & dosagem , Nitrato de Uranil
6.
Biopharm Drug Dispos ; 30(6): 305-17, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19639551

RESUMO

The pharmacokinetics of mirodenafil and its two metabolites, SK3541 and SK3544, after intravenous (5, 10, 20 and 50 mg/kg) and oral (10, 20 and 50 mg/kg) administration of mirodenafil, and the first-pass effect of mirodenafil after intravenous, oral, intraportal, intragastric and intraduodenal (20 mg/kg) administration of mirodenafil were evaluated in rats. The pharmacokinetics of mirodenafil and SK3541 were dose-dependent after both intravenous and oral administration of mirodenafil due to the saturable hepatic metabolism of mirodenafil. After oral administration of mirodenafil, approximately 2.59% of the oral dose was not absorbed, the F value was approximately 29.4%, and the hepatic and gastrointestinal first-pass effects of mirodenafil were approximately 21.4% and 54.3% of the oral dose, respectively. The low F value of mirodenafil in rats was mainly due to considerable hepatic and gastrointestinal first-pass effects in rats. The equilibrium plasma-to-blood cell partition ratios of mirodenafil were independent of the initial blood mirodenafil concentrations of 1-10 microg/ml; the mean values were 1.08-1.21. The plasma binding values of mirodenafil to rat plasma was 87.8%.


Assuntos
Ereção Peniana/fisiologia , Inibidores da Fosfodiesterase 5 , Pirimidinonas/administração & dosagem , Pirimidinonas/farmacocinética , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacocinética , Animais , Relação Dose-Resposta a Droga , Masculino , Ereção Peniana/efeitos dos fármacos , Pirimidinonas/química , Ratos , Ratos Sprague-Dawley , Sulfonamidas/química , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
7.
Med J Malaysia ; 61(2): 173-80, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16898308

RESUMO

Pre-eclampsia or pregnancy induced hypertension (PIH) affects 6-8% of all pregnancies. Although the underlying mechanism of PIH is still unknown, it is widely believed that the placenta plays an important role. It was thought that an ischemic placenta due to poor perfusion can precipitate the signs and symptoms of PIH. This study aims to investigate the possible role of Type 1(AT1) and Type 2 (AT2) angiotensin II receptor subtypes in the mechanism of PIH. AT1 receptor stimulation causes vasoconstriction and AT2 receptor stimulation causes vasodilatation. Investigating the interactions of these two receptors in the placenta provides an insight as to the balance that may exist between AT1 and AT2 receptors in normal pregnancy. Any disruption to the balance might cause a disruption of the blood flow in the placenta, leading to PIH. Placentas were collected from 11 PIH patients and 11 normal patients. Immunohistochemistry techniques were performed on the placental tissue to determine the distribution of AT1 and AT2 receptors in the placental tissue qualitatively and quantitatively. It was observed that in normal patients, the balance between AT1 and AT2 receptors is that the level of AT2 receptors is higher than the level of AT1 receptors. However in the PIH patient, it was observed that the normal balance was disrupted. In PIH patients the level of AT1 receptors was observed to be higher than the level of AT2 receptors. This study suggests that disruption of the balance between AT1 and AT2 receptors observed in PIH placentas might cause a decrease in blood flow to the placenta, causing it to be poorly perfused. This may cause placental ischemia which may lead to PIH.


Assuntos
Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez/metabolismo , Receptores de Angiotensina/metabolismo , Biomarcadores/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Prognóstico
8.
Oncogene ; 25(31): 4286-99, 2006 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-16518409

RESUMO

When aberrantly expressed or activated, the Met receptor tyrosine kinase is involved in tumor invasiveness and metastasis. In this study, we have used the Xenopus embryonic system to define the role of various Met proximal-binding partners and downstream signaling pathways in regulating an induced morphogenetic event. We show that expression of an oncogenic derivative of the Met receptor (Tpr-Met) induces ectopic morphogenetic structures during Xenopus embryogenesis. Using variant forms of Tpr-Met that are engineered to recruit a specific signaling molecule of choice, we demonstrate that the sole recruitment of either the Grb2 or the Shc adaptor protein is sufficient to induce ectopic structures and anterior reduction, while the recruitment of PI-3Kinase (PI-3K) is necessary but not sufficient for this effect. In contrast, the recruitment of PLCgamma can initiate the induction, but fails to maintain or elongate supernumerary structures. Finally, evidence indicates that the Ras/Raf/MAPK pathway is necessary, but not sufficient to induce these structures. This study also emphasizes the importance of examining signaling molecules in the regulatory context that is provided by receptor/effector interactions when assessing a role in cell growth and differentiation.


Assuntos
Embrião não Mamífero/metabolismo , Indução Embrionária/fisiologia , Proteínas Proto-Oncogênicas c-met/fisiologia , Animais , Feminino , Mutação , Fosforilação , Proteínas Proto-Oncogênicas c-met/genética , Xenopus
9.
Antonie Van Leeuwenhoek ; 88(1): 1-12, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15928972

RESUMO

The correlation of contraction by an actomyosin band with the closing of the septum of dividing cells of the fission yeast, Schizosaccharomyces pombe, cannot suggest cause-and-effect because contraction would be apparent whether the membrane enveloping the centripetally closing septum were pulled or were pushed. Thus the common observation of contraction is not critical. Diagrams of published electron micrographs of dividing wild-type fission yeasts illustrate variable (tilted) septal images that are counterintuitive to a pull model. Circumference calculations based on those images suggest that some variable forms might be only 6% closed even though their two-dimensional profiles would be 50% closed, if they were not tilted. Development of multiseptate forms of cdc4-8 and cdc4-377 temperature sensitive mutants incubated at their restrictive temperature was followed. These multiseptate forms are shown to have functional (functional in terms of generating divided uninucleate cytoplasts) but grotesque septa which are formed in the absence of actomyosin bands. By contrast, the myosin of the plant phragmoplast is not properly oriented for contractility, and Dictyostelium (attached cells) and Saccharomyces (mutants) have been shown to divide in the absence of myosin II, just as S. pombe does (above). Hence contractility, the essence of a pull model for septum closure, would seem to be non-essential. Other, non-contractile mechanisms of myosin are emphasized, and a push model becomes a rational default hypothesis. The essence of push models is that their synthesis/assembly mechanisms are driving force sufficient for septum closure.


Assuntos
Divisão Celular , Modelos Biológicos , Schizosaccharomyces/citologia , Actinas , Forma Celular , Miosinas , Fenótipo , Proteínas de Schizosaccharomyces pombe
10.
Oncogene ; 16(18): 2367-80, 1998 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-9620554

RESUMO

Human hepatitis B virus (HBV) is one of the causative agents of hepatocellular carcinoma (HCC). The virus encodes a 17 kDa protein, X, which is known to be a causative agent in the formation of HCC. An insulin-like growth factor-II (IGF-II) is expressed during the formation of HCC. Among the four promoters of the IGF-II gene, promoters 2, 3 and 4 become activated during the formation of HCC. The high frequency of detection of hepatitis B virus X (HBV-X) antigen in liver cells from patients with chronic hepatitis, cirrhosis, and liver cancer suggested that the expressions of HBV-X and IGF-II are associated. Studies were carried out to test the relationship between the HBV-X gene product and the activation of IGF-II promoter 4. We demonstrated that the HBV-X protein increases the endogenous IGF-II expression from promoter 3 and 4 of IGF-II gene. Analysis of the fourth promoter of IGF-II gene showed that the HBV-X gene product positively regulates transcription. Two copies of a motif are responsible for conferring HBV-X regulation on the fourth promoter of IGF-II. These motifs have been identified as Sp1 binding sites. Sp1 binding to IGF-II P4 promoter was identified by gel mobility shift assay using purified Sp1. By using a GAL4-Sp1 fusion protein it was demonstrated that HBV-X positively regulates the Spl mediated transcriptional activity of IGF-II in vivo. A protein-affinity chromatography experiment showed that HBV-X protein does not bind directly to Sp1, but HBV-X does augment the DNA binding activity of the phosphorylated form of Sp1 in HepG2 cells. Sp1 was phosphorylated by HBV-X and its DNA-binding activity was up-regulated upon HBV-X transfections. Various HBV-X mutant expression vectors were used for the demonstration of specific interactions between Sp1 and HBV-X. These results indicate that HBV-X functions as a positive regulator of transcription, and that Sp1 is a direct target for the transcriptional regulation of IGF-II. Increasing the DNA binding ability of the phosphorylated form of Sp1 by HBV-X might be an important mechanism for regulating the IGF-II gene expression and possibly promoting cell division during hepatic carcinogenesis. Our experimental results suggest that expression of HBV-X might induce the expression of IGF-II and the IGF-II might play a role in hepatitis B virus pathogenesis during the formation of HCC.


Assuntos
Vírus da Hepatite B , Fator de Crescimento Insulin-Like II/biossíntese , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/metabolismo , Transativadores/metabolismo , Sítios de Ligação , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/genética , Sequência Consenso , Análise Mutacional de DNA , Regulação da Expressão Gênica , Humanos , Fator de Crescimento Insulin-Like II/genética , Fosforilação , Ligação Proteica , Deleção de Sequência , Transcrição Gênica , Células Tumorais Cultivadas , Proteínas Virais Reguladoras e Acessórias
11.
Biochim Biophys Acta ; 1380(2): 156-8, 1998 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-9565676

RESUMO

Complementary DNAs encoding the heavy and light chains of the Fab fragment of mouse agglutinating monoclonal antibody against human red blood cells were cloned by polymerase chain reaction and their nucleotide sequences were determined. The sequence analysis showed that the variable regions of the heavy and light chains were the members of mouse heavy-chain subgroup IIa and kappa light-chain subgroup I, respectively. A few unusual amino acids in the constant regions of the heavy chain were also recognized.


Assuntos
Anticorpos Monoclonais/genética , DNA Complementar/análise , Hemaglutininas/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias kappa de Imunoglobulina/genética , Idoso , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Hemaglutininas/genética , Humanos , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/química , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Cadeias kappa de Imunoglobulina/imunologia , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
12.
Gene ; 207(2): 111-8, 1998 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-9511751

RESUMO

We prepared human hepatoma cell lines, which expressed the human hepatitis B virus-X gene product. The plasmid pMAMneo-X, containing an HBV-X gene promoter, an enhancer and a structural gene was constructed. Transfected HBV-X gene integration and expression were detected by Southern and Northern blotting, as well as by chloramphenicol acetylase transferase (CAT) assay using various kinds of promoter-CAT reporter systems. HBV-X protein expression in stable transfectants was confirmed by immunofluorescence microscopy. Transfected cell lines showed permanent expression of HBV-X proteins. The HBV-X transfectant activated its target promoters in promoter-CAT constructs as reporters. The HBV-X transfectant enhanced AP-1 transcription factor binding to its target DNA. Therefore, X-transfectants are not only stable, but also have specific biological functions. Cell cycle analysis by flow cytometry showed that the majority of the transfectant cells are arrested in the G1 or G2 phase of the cell cycle. These cell lines may be useful in analyzing the biological functions of HBV-X and its functional role in the formation of hepatocellular carcinomas.


Assuntos
Vírus da Hepatite B/genética , Transativadores/genética , Carcinoma Hepatocelular , Divisão Celular , Clonagem Molecular , Fase G1 , Fase G2 , Genes Virais , Humanos , Microscopia de Fluorescência , Regiões Promotoras Genéticas , Transativadores/biossíntese , Fator de Transcrição AP-1/metabolismo , Ativação Transcricional , Transfecção , Células Tumorais Cultivadas , Proteínas Virais Reguladoras e Acessórias
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