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1.
Br J Cancer ; 130(3): 467-475, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38129525

RESUMO

BACKGROUND: Berzosertib (M6620) is a highly potent (IC50 = 19 nM) and selective, first-in-class ataxia telangiectasia-mutated and Rad3-related protein kinase (ATR) inhibitor. This trial assessed the safety, preliminary efficacy, and tolerance of berzosertib in oesophageal cancer (A1 cohort) with RT and advanced solid tumours (A2 cohort) with cisplatin and capecitabine. METHODS: Single-arm, open-label dose-escalation (Time-to-Event Continual Reassessment Method) trial with 16 patients in A1 and 18 in A2. A1 tested six dose levels of berzosertib with RT (35 Gy over 15 fractions in 3 weeks). RESULTS: No dose-limiting toxicities (DLTs) in A1. Eight grade 3 treatment-related AEs occurred in five patients, with rash being the most common. The highest dose (240 mg/m2) was determined as the recommended phase II dose (RP2D) for A1. Seven DLTs in two patients in A2. The RP2D of berzosertib was 140 mg/m2 once weekly. The most common grade ≥3 treatment-related AEs were neutropenia and thrombocytopenia. No treatment-related deaths were reported. CONCLUSIONS: Berzosertib combined with RT is feasible and well tolerated in oesophageal cancer patients at high palliative doses. Berzosertib with cisplatin and capecitabine was well tolerated in advanced cancer. Further investigation is warranted in a phase 2 setting. CLINICAL TRIALS IDENTIFIER: EU Clinical Trials Register (EudraCT) - 2015-003965-27 ClinicalTrials.gov - NCT03641547.


Assuntos
Neoplasias Esofágicas , Isoxazóis , Pirazinas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina/uso terapêutico , Quimiorradioterapia , Cisplatino/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Isoxazóis/uso terapêutico , Dose Máxima Tolerável , Pirazinas/uso terapêutico
2.
Ann Rheum Dis ; 73(1): 56-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24067785

RESUMO

OBJECTIVE: The primary objective of the study was to explore safety and tolerability of hyperimmune caprine serum (AIMSPRO) in established diffuse cutaneous systemic sclerosis (SSc). Secondary objectives included assessment of potential efficacy and biological activity and exploration of candidate biomarkers. METHODS: This was a double-blind parallel group randomised placebo-controlled clinical trial. After informed consent 20 patients with established diffuse cutaneous SSc of greater than 3 years duration not receiving immunosuppressive therapy were randomised to receive either active (n=10) or placebo formulation (n=10) by subcutaneous twice weekly injection over 26 weeks. Clinical assessments were evaluated over 26 weeks. RESULTS: There were no safety concerns during this study. Frequency of adverse events was not different between active and placebo groups. Mean modified Rodnan Skin Score (mRSS) fell by 1.4±4.7 units with active treatment but increased by 2.1±6.4 units on placebo when baseline values were compared with 26 weeks and responder analysis showed clinically meaningful improvement in mRSS at 26 weeks in 5 (50%) of actively treated patients compared with 1 (10%) in the control group (p=0.062). PIIINP (µg/L) showed a comparatively larger increase in the treatment group compared with the placebo group, (p=0.0118). CONCLUSIONS: These results confirm tolerability and safety of this novel biological agent in established diffuse SSc. The value of a placebo treated control group in small clinical trials evaluating skin disease in SSc is confirmed. Potential improvement in mRSS and changes in PIIINP in cases receiving active therapy suggest that this intervention may be of clinical benefit and warrants further evaluation.


Assuntos
Soros Imunes/administração & dosagem , Fatores Imunológicos/administração & dosagem , Esclerodermia Difusa/tratamento farmacológico , Esclerodermia Difusa/imunologia , Adulto , Idoso , Animais , Biomarcadores/sangue , Estudos de Viabilidade , Feminino , Cabras , Humanos , Soros Imunes/efeitos adversos , Fatores Imunológicos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Esclerodermia Difusa/patologia , Resultado do Tratamento
3.
Phys Rev Lett ; 109(4): 048301, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-23006113

RESUMO

We derive a thermodynamic identity that allows one to infer the change in the number of screening ions that are associated with a charged macromolecule as the macromolecule is continuously stretched. Applying this identity to force-extension data on both single-stranded and double-stranded DNA, we find that the number of polymer-associated ions depends nontrivially on both the bulk salt concentration and the bare rigidity of the polymer, with single-stranded DNA exhibiting a relatively large decrease in ion excess upon stretching. We rationalize these observations using simple models for polyelectrolyte extension.


Assuntos
DNA de Cadeia Simples/química , DNA/química , Modelos Químicos , Ânions/química , Cátions/química , Eletrólitos/química
4.
Int J Clin Pract ; 65(1): 73-81, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21078010

RESUMO

BACKGROUND: This study was designed to assess clinical and functional outcomes associated with switching to duloxetine treatment in patients with major depressive disorder (MDD) experiencing emotional and painful physical symptoms in their current episode. METHODS: In this 8-week, multinational, multicentre, single-arm, open-label clinical trial, 242 MDD patients were switched to duloxetine 60 mg/day after selective serotonin reuptake inhibitor (SSRI) or serotonin and norepinephrine reuptake inhibitor (SNRI) treatment. The primary analysis compared mean change from baseline in Brief Pain Inventory-Modified Short Form (BPI-SF) interference score between initial responders [≥ 50% reduction from baseline on the 17-item Hamilton Depression Rating Scale (HAMD(17)) Maier subscale] and initial non-responders after 4 weeks. Initial responders continued with duloxetine 60 mg/day. Initial non-responders received duloxetine 120 mg/day for the remaining 4 weeks. Depression, pain, anxiety and functional outcomes were also compared after 8 weeks. RESULTS: BPI-SF interference decreased from baseline in initial responders (n = 108) and initial non-responders (n = 85) after 4 weeks of duloxetine treatment, with greater reductions in initial responders [BPI-SF mean difference in reduction: 1.01 (95% CI 0.42-1.61); p < 0.001]. Reductions in pain interference favouring initial responders were also apparent after 8 weeks [0.68 (95% CI: 0.03-1.33); p = 0.042]. Depression, pain, anxiety and function improved over 8 weeks across patient groups. CONCLUSIONS: Elements of core mood and pain are important residual symptoms following poor treatment response in MDD. Early improvement in these symptoms after switching to duloxetine indicated an increased chance of functional recovery.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Tiofenos/uso terapêutico , Adulto , Sintomas Afetivos/tratamento farmacológico , Dor Crônica/prevenção & controle , Cloridrato de Duloxetina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
J Cell Biol ; 141(1): 101-14, 1998 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-9531551

RESUMO

The molecular mechanisms mediating cell surface trafficking of caveolae are unknown. Caveolae bud from plasma membranes to form free carrier vesicles through a "pinching off" or fission process requiring cytosol and driven by GTP hydrolysis (Schnitzer, J.E., P. Oh, and D.P. McIntosh. 1996. Science. 274:239-242). Here, we use several independent techniques and functional assays ranging from cell-free to intact cell systems to establish a function for dynamin in the formation of transport vesicles from the endothelial cell plasma membrane by mediating fission at the neck of caveolae. This caveolar fission requires interaction with cytosolic dynamin as well as its hydrolysis of GTP. Expression of dynamin in cytosol as well as purified recombinant dynamin alone supports GTP-induced caveolar fission in a cell-free assay whereas its removal from cytosol or the addition to the cytosol of specific antibodies for dynamin inhibits this fission. Overexpression of mutant dynamin lacking normal GTPase activity not only inhibits GTP-induced fission and budding of caveolae but also prevents caveolae-mediated internalization of cholera toxin B chain in intact and permeabilized endothelial cells. Analysis of endothelium in vivo by subcellular fractionation and immunomicroscopy shows that dynamin is concentrated on caveolae, primarily at the expected site of action, their necks. Thus, through its ability to oligomerize, dynamin appears to form a structural collar around the neck of caveolae that hydrolyzes GTP to mediate internalization via the fission of caveolae from the plasma membrane to form free transport vesicles.


Assuntos
Caveolinas , Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Invaginações Revestidas da Membrana Celular/fisiologia , Invaginações Revestidas da Membrana Celular/ultraestrutura , Endotélio Vascular/fisiologia , GTP Fosfo-Hidrolases/fisiologia , Guanosina Trifosfato/metabolismo , Animais , Anticorpos , Bovinos , Caveolina 1 , Sistema Livre de Células , Células Cultivadas , Clatrina/fisiologia , Citosol/fisiologia , Dinaminas , Endotélio Vascular/citologia , Endotélio Vascular/ultraestrutura , GTP Fosfo-Hidrolases/antagonistas & inibidores , Células HeLa , Humanos , Proteínas de Membrana/metabolismo , Microcirculação , Modelos Biológicos , Circulação Pulmonar , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Transfecção
6.
Science ; 274(5285): 239-42, 1996 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-8824187

RESUMO

Caveolae are specialized invaginated cell surface microdomains of undefined function. A cell-free system that reconstituted fission of caveolae from lung endothelial plasma membranes was developed. Addition of cytosol and the hydrolysis of guanosine triphosphate (GTP) induced caveolar fission. The budded caveolae were isolated as vesicles rich in caveolin and the sialoglycolipid GM1 but not glycosyl-phosphatidylinositol (GPI)-anchored proteins. These vesicles contained the molecular machinery for endocytosis and transcytosis. In permeabilized endothelial cells, GTP stimulated, whereas GTPgammaS prevented, caveolar budding and endocytosis of the cholera toxin B chain to endosomes. Thus, caveolae may bud to form discrete carrier vesicles that participate in membrane trafficking.


Assuntos
Caveolinas , Membrana Celular/metabolismo , Guanosina Trifosfato/metabolismo , Animais , Transporte Biológico , Bovinos , Caveolina 1 , Membrana Celular/química , Membrana Celular/ultraestrutura , Sistema Livre de Células , Centrifugação com Gradiente de Concentração , Toxina da Cólera/metabolismo , Endocitose , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Trifosfato/farmacologia , Hidrólise , Proteínas de Membrana/análise , Proteínas de Membrana/metabolismo , Ratos
7.
Science ; 269(5229): 1435-9, 1995 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-7660128

RESUMO

In situ coating of the surface of endothelial cells in rat lung with cationic colloidal silica particles was used to separate caveolae from detergent-insoluble membranes rich in glycosyl phosphatidylinositol (GPI)-anchored proteins but devoid of caveolin. Immunogold electron microscopy showed that ganglioside GM1-enriched caveolae associated with an annular plasmalemmal domain enriched in GPI-anchored proteins. The purified caveolae contained molecular components required for regulated transport, including various lipid-anchored signaling molecules. Such specialized distinct microdomains may exist separately or together in the plasma membrane to organize signaling molecules and to process surface-bound ligands differentially.


Assuntos
Caveolinas , Membrana Celular/química , Membrana Celular/ultraestrutura , Glicosilfosfatidilinositóis/análise , Proteínas de Membrana/análise , 5'-Nucleotidase/análise , Animais , Caveolina 1 , Fracionamento Celular , Coloides , Detergentes , Endotélio Vascular/ultraestrutura , Microscopia Imunoeletrônica , Ratos , Receptores de Superfície Celular/análise , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Transdução de Sinais , Dióxido de Silício , Solubilidade
8.
Emerg Med J ; 26(5): 334-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19386866

RESUMO

BACKGROUND: Emergency abdominal aortic aneurysm (EmAAA) represents a spectrum of disease from symptomatic non-ruptured aneurysms to free intraperitoneal rupture, with significantly worse outcomes for patients in a haemodynamically shocked state before surgery. A study was undertaken to see if the preoperative journey and outcome were different in patients who deviated from the classic acutely shocked presentation. METHODS: An observational database compiled from case notes of patients undergoing surgery for EmAAA at Sunderland Royal Hospital between April 2000 and October 2006 was interrogated to examine details of patient preoperative journey, physiological status and 30-day survival. Comparison between groups was performed using chi(2) analysis and the Mann-Whitney U test where appropriate. RESULTS: Records for 98 patients were available for review. Overall 30-day mortality was 49%, and was significantly higher for patients in shock at induction of anaesthesia than in those who were haemodynamically stable (59.6% vs 34.1%, p = 0.01). At presentation, 56 patients were stable and misdiagnosis was significantly more common in these patients than in those who were in shock (58.9% vs 26.2%, p = 0.002), with a significantly increased median time delay from presentation to diagnosis (144 min (IQR 24-366) vs 12 min (IQR 0-42), p<0.0001). Median time from diagnosis to arrival in theatre was significantly longer in patients who were haemodynamically stable at presentation (90 min (IQR 60-150) vs 48 min (IQR 36-90), p = 0.02). Of the 56 patients who were haemodynamically stable at presentation, 19 underwent haemodynamic decompensation before surgery with a significantly increased mortality compared with those who remained stable (73.7% vs 37.8%, p = 0.02). Of these 19 patients, only 5 were correctly diagnosed at presentation. CONCLUSIONS: Diagnosis and treatment of EmAAA in haemodynamically stable patients is often delayed, with the risk of significant rupture and haemodynamic decompensation which is associated with poor outcome. Correct diagnosis and treatment before development of shock has the potential to reduce mortality.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico , Choque/etiologia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/complicações , Ruptura Aórtica/diagnóstico , Ruptura Aórtica/cirurgia , Diagnóstico Diferencial , Emergências , Serviço Hospitalar de Emergência/normas , Métodos Epidemiológicos , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
9.
Opt Express ; 16(13): 9365-71, 2008 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-18575500

RESUMO

We designed and fabricated Ge/Si avalanche photodiodes grown on silicon substrates. The mesa-type photodiodes exhibit a responsivity at 1310 nm of 0.54 A/W, a breakdown voltage thermal coefficient of 0.05%/ degrees C, a 3 dB-bandwidth of 10 GHz. The gain-bandwidth product was measured as 153 GHz. The effective k value extracted from the excess noise factor was 0.1.


Assuntos
Cristalização/métodos , Germânio/química , Modelos Teóricos , Fotometria/instrumentação , Semicondutores , Silício/química , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação , Sensibilidade e Especificidade
10.
Int J Pediatr Otorhinolaryngol ; 72(3): 377-83, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18191234

RESUMO

OBJECTIVE: Peri-orbital infections can be classified as pre-septal or post-septal depending upon the location of the focus of infection. The ability to differentiate between these two is frequently difficult at the initial presentation, with marked orbital edema and pain limiting the ophthalmic examination. Hence, it is important to identify all the features at presentation that will lead to an accurate and rapid diagnosis and treatment. Our retrospective review of peri-orbital infections identifies contrasting features between these two groups that will aid the clinician in the subsequent management of these infections. DESIGN AND SETTING: A retrospective review over an 11-year period of children admitted to a tertiary children's hospital for the treatment of peri-orbital cellulitis was undertaken. The two subgroups were identified, those suffering from a pre-septal infection and those with a post-septal infection. The groups were compared with respect to their presentation, clinical findings, findings on CT and surgical intervention. RESULTS: Two hundred and sixty-two children were identified with peri-orbital infections, 227 pre-septal, and 35 post-septal. There were statistically significant differences between the pre- and post-septal groups with regards to the following: age (3.9 vs. 7.5 years, p<0.001), medical co-morbidities (19% vs. 0%, p<0.01), a history of trauma (40% vs. 11% of cases, p<0.003), clinical diagnosis of acute sinusitis (9% vs. 91% of cases, p<0.001), and fever (47% vs. 94%, p<0.001). Ophthalmologic examination identified diplopia (p<0.001), opthalmoplegia (p<0.001) and proptosis (p<0.001) as significant features of a post-septal infection. Intravenous antibiotics were successful in treating the majority of cases, with 5% of pre-septal, and 25% of post-septal infections requiring surgery. CONCLUSION: When considering the management of a child with a peri-orbital infection, features from the history and examination such as trauma, medical co-morbidities and ophthalmic signs will guide management and delineate the indications for early CT imaging. In the absence of acute visual compromise or other signs of disease progression, initial management with intravenous antibiotics for 48 h to cover Staphylococcal aureus and Streptococcal pyogenes with nasal decongestant should be considered before surgical intervention is contemplated. A multi team approach is essential in obtaining the best outcome for the child.


Assuntos
Infecções Bacterianas/complicações , Septo Nasal/microbiologia , Doenças Orbitárias/classificação , Doenças Orbitárias/microbiologia , Algoritmos , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Criança , Pré-Escolar , Feminino , Humanos , Injeções Intravenosas , Masculino , Doenças Orbitárias/tratamento farmacológico , Estudos Retrospectivos
11.
Int J Pediatr Otorhinolaryngol ; 71(10): 1573-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17628703

RESUMO

INTRODUCTION: Acute bacterial sinusitis is common in the pediatric population. Intracranial spread of infection is a rare but life-threatening complication of acute sinusitis. Due to the infrequent presentation of this complication, there are no well-defined management protocols for the acute sinusitis. CASE SERIES: We present three pediatric cases where children presented with intracranial sepsis, and the underlying source of infection was from the paranasal sinuses. In all cases, endoscopic sinus surgery was performed in the acute setting, with the use of frontal sinus mini-trephines playing a significant role. DISCUSSION: We describe our experience and review the available literature.


Assuntos
Infecções do Sistema Nervoso Central/epidemiologia , Sinusite Frontal , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Trepanação/métodos , Doença Aguda , Infecções do Sistema Nervoso Central/diagnóstico por imagem , Infecções do Sistema Nervoso Central/cirurgia , Criança , Pré-Escolar , Feminino , Sinusite Frontal/diagnóstico por imagem , Sinusite Frontal/epidemiologia , Sinusite Frontal/cirurgia , Humanos , Masculino , Tomografia Computadorizada por Raios X
12.
Int J Pediatr Otorhinolaryngol ; 71(10): 1623-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17643498

RESUMO

The utility of angiography and embolisation of selected branches of the external carotid artery is occasionally helpful in the management of recurrent epistaxis, pre-operative devascularisation of tumours such as angiofibromas, and other head and neck conditions. The use of embolisation for recalcitrant post-tonsillectomy bleeding due to the formation of an aneurysm or pseudoaneurysm of branches of the external carotid artery has been described [P. Simoni, J. Bello, B. Kent, Pseudoaneurysm of the lingual artery secondary to tonsillectomy treated with selective embolization, Int. J. Pediatr. Otorhinolaryngol. 59 (2) (2001) 125-128]. There are also reports of pseudoaneurysm formation on the internal carotid following tonsillectomy [F. Tovi, A. Leiberman, Y. Hertzanu, L. Golcman, Pseudoaneurysm of the internal carotid artery secondary to tonsillectomy, Int. J. Pediatr. Otolaryngol. 13 (1987) 69-75]. The repeated presentation of a 5-year-old girl with post-operative tonsillectomy bleeding on three separate occasions, each approximately 1 week apart, prompted the consideration of the diagnosis of aneurysm formation, and hence, angiography was performed. The anomalous finding from this study precluded embolisation due to the risk of blindness. This experience has prompted this review which highlights the important issues of angiographic assessment prior to embolisation. The relevance of this to external carotid artery ligation is also reflected upon.


Assuntos
Artéria Carótida Externa/fisiologia , Órbita/irrigação sanguínea , Adenoidectomia , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/cirurgia , Artéria Carótida Interna/fisiologia , Pré-Escolar , Embolização Terapêutica , Feminino , Humanos , Complicações Pós-Operatórias , Hemorragia Pós-Operatória/terapia , Tonsilectomia
14.
Bone Rep ; 7: 137-144, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29124084

RESUMO

Second-harmonic generation imaging (SHG) captures triple helical collagen molecules near tissue surfaces. Biomedical research routinely utilizes various imaging software packages to quantify SHG signals for collagen content and distribution estimates in modern tissue samples including bone. For the first time using SHG, samples of modern, medieval, and ice age bones were imaged to test the applicability of SHG to ancient bone from a variety of ages, settings, and taxa. Four independent techniques including Raman spectroscopy, FTIR spectroscopy, radiocarbon dating protocols, and mass spectrometry-based protein sequencing, confirm the presence of protein, consistent with the hypothesis that SHG imaging detects ancient bone collagen. These results suggest that future studies have the potential to use SHG imaging to provide new insights into the composition of ancient bone, to characterize ancient bone disorders, to investigate collagen preservation within and between various taxa, and to monitor collagen decay regimes in different depositional environments.

15.
J Anim Sci ; 95(7): 3143-3153, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28727080

RESUMO

Native grasses, such as switchgrass (SG; L.), big bluestem (BB; Vitman), indiangrass (IG; Nash), and eastern gamagrass (EG; [L.] L.) may be capable of providing desirable summer forage for cattle as well as a source of biomass for renewable energy. To evaluate that potential, experiments were conducted at 2 locations in Tennessee comparing weaned beef () steers (268 ± 25 kg initial BW) during early-season grazing (Early; 30 d, typically corresponding to May, followed by postdormancy biomass harvest) and full-season grazing (Full, mean duration = 98 d). For Exp. 1, which compared SG, a blend of BB and IG (BBIG), and EG, ADG was greater ( < 0.05) for BBIG (1.02 kg/d) than SG (0.85 kg/d), and both were greater ( < 0.05) than EG (0.66 kg/d). Grazing days for SG and EG were similar (389 and 423 animal unit days [AUD]/ha, respectively) and exceeded ( < 0.05) that of BBIG (233 AUD/ha) during Full. In Exp. 2 (SG and BBIG only), rates of gain were comparable to that of Exp. 1, but AUD were 425 (SG) and 299 (BBIG) AUD/ha. Such rates of gain and grazing days indicate that these grasses can provide desirable summer forage for growing cattle. Early produced 211 to 324 kg BW gain/ha, depending on experiment and forage, followed by dormant-season harvests of 7.5 to 10.5 Mg/ha of biomass, indicating a potential for beef cattle forage and biomass production on the same land resource. Native grasses provided productive summer pasture and good rates of gain on growing cattle and could contribute to forage programs, especially where cool-season grasses currently predominate.


Assuntos
Ração Animal/análise , Bovinos , Poaceae , Estações do Ano , Agricultura , Animais , Biomassa , Masculino , Tennessee
17.
Biochim Biophys Acta ; 690(2): 224-30, 1982 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-6982072

RESUMO

This study describes the liposome-mediated delivery of toxins to a variety of cells in vitro. Gelonin, a potent inhibitor of protein synthesis from Gelonium multiflorum, was delivered to the cytoplasm of TLX5 lymphoma cells most effectively by phosphatidylserine vesicles. These liposomes were also capable in inhibiting protein synthesis in XC (transformed rat fibroblasts) and phytohaemagglutinin-stimulated CBA mouse lymphocytes. Phosphatidylcholine liposomes had no capacity to deliver their contents to the cytoplasm, but the addition of cholesterol to the vesicle membrane resulted in an increased capacity. Delivery events were enhanced further by the addition of mixed bovine brain gangliosides to the membrane in the ratio 5:5:1 phosphatidylcholine/ cholesterol/gangliosides. The addition of cholesterol to phosphatidylserine vesicles failed to increase the inhibitory effects of the gelonin liposomes. The A chain of diphtheria toxin encapsulated in phosphatidylserine liposomes had no inhibitory effect on the level of protein synthesis in TLX5 or Daudi cells.


Assuntos
Leucemia Linfoide/metabolismo , Lipossomos , Linfócitos/metabolismo , Linfoma/metabolismo , Fosfatidilserinas/farmacologia , Proteínas de Plantas/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Cinética , Camundongos , Neoplasias Experimentais/metabolismo , Coelhos , Ratos , Reticulócitos/efeitos dos fármacos , Reticulócitos/metabolismo , Proteínas Inativadoras de Ribossomos Tipo 1 , Ribossomos/efeitos dos fármacos , Linfócitos T/metabolismo
18.
Biochim Biophys Acta ; 1354(1): 83-96, 1997 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-9375796

RESUMO

A restriction fragment length polymorphism (RFLP) in the human glycoprotein hormone common alpha-subunit gene has been identified and partially characterized in normal lymphocytes and placentae, established tumor cell lines, and tumor biopsy samples. High molecular weight DNA was digested with the restriction endonuclease MspI, separated by electrophoresis in agarose gels, transferred to nylon membranes by the method of Southern, and hybridized to 32P-labeled human chorionic gonadotropin alpha-subunit cDNA. After autoradiography, bands were detected at 5.3, 3.3, 2.1, 1.6, 0.8 and 0.6 kbp. Presence of the 5.3, 3.3 and 0.6 kbp bands was invariant and uninformative. Patterns missing the 0.8 kbp band and both the 2.1 and 1.6 kbp bands are consistent with separate alleles that occur in placental and lymphocyte DNA with frequencies of 0.44 (15/34) and 0.06 (2/34), respectively. Presence of all three bands (2.1, 1.6 and 0.8 kbp) is indicative of heterozygosity, occurring at a frequency of 0.50 (17/34). Additional restriction patterns, not yet observed in DNA isolated from term placentae or circulating lymphocytes, were detected in DNA obtained from tumor cell lines and fresh tumor tissues at frequencies of 0.79 (15/19) and 0.59 (10/17), respectively. Thus, particular alpha-subunit genotypes are disproportionately represented in tumor-derived DNA, occurring at frequencies 10- to 13-times higher than would be predicted from their occurrence in normal tissue. Paired normal and tumor tissues from the same individual exhibited identical hybridization patterns, suggesting that this RFLP may be representative of a predisposition toward a variety of neoplasias rather than indicative of a change in DNA structure at or near this locus as a result of tumor development.


Assuntos
Desoxirribonuclease HpaII/metabolismo , Subunidade alfa de Hormônios Glicoproteicos/genética , Neoplasias/genética , Feminino , Genótipo , Mutação em Linhagem Germinativa , Humanos , Masculino , Linhagem , Polimorfismo de Fragmento de Restrição , Células Tumorais Cultivadas
19.
Biochim Biophys Acta ; 717(2): 272-7, 1982 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-7115768

RESUMO

Anti-mouse lymphocyte globulin and normal immunoglobulin have been conjugated to abrin using two procedures, one involving linkage through an amide bond and a piperazine ring and the other the introduction of two amide bonds flanking a disulphide bridge. The four conjugates produced were equipotent as inhibitors of protein synthesis in rabbit reticulocyte lysates. Each antibody-containing conjugate was a more effective inhibitor of protein synthesis in cultured cells than the equivalent normal immunoglobulin-containing conjugate. In addition the conjugates with disulphide linkage groups were ten times more potent than their counterparts. The disulphide conjugates were also twice as toxic to mice in an acute toxicity test but when used to suppress their immune responses to sheep red blood cells it was the non-disulphide-linked conjugates that were superior. In all instances antibody-containing conjugates were more powerful immunosuppressants than those containing normal IgG. The results are taken to indicate a relative lack of stability of the disulphide conjugates in the tissues.


Assuntos
Abrina/imunologia , Complexo Antígeno-Anticorpo , Globulinas/imunologia , Linfócitos/imunologia , Proteínas de Plantas/imunologia , Animais , Fenômenos Químicos , Química , Clorambucila , Dissulfetos , Ditiotreitol/farmacologia , Imunoglobulina G , Indicadores e Reagentes , Cinética , Camundongos , Baço/imunologia , Succinimidas
20.
Cochrane Database Syst Rev ; (4): CD004593, 2005 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-16235368

RESUMO

BACKGROUND: The use of peripheral intravenous cannulae is common in newborn babies. Many of them require an intravenous line only for medications and not for fluid. Currently there is little uniformity in methods used to maintain cannula patency. OBJECTIVES: The object of this review was to determine which method was better for maintaining intravenous lines used in neonates for intravenous medication only: intermittent flushing or continuous infusion SEARCH STRATEGY: We searched The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2, 2004), CINAHL (from 1982 to June 2004) and MEDLINE (from 1966 to June 2004) . SELECTION CRITERIA: Randomised controlled trials comparing continuous infusion to intermittent flushing to maintain patency of intravenous cannulas. Units of randomisation might include individual catheters or individual babies. DATA COLLECTION AND ANALYSIS: Three reviewers independently assessed trial quality and extracted data. MAIN RESULTS: Two studies were eligible for inclusion. In one study only one of our primary outcomes was available: the duration of cannula patency for the first cannula used per infant was slightly longer in the continuous infusion group, but not significantly so, with a mean difference of -4.3 hours (95% CI -18.2 to 9.7). In the second study, only one of our primary outcomes was available: the mean (SD) number cannulas used per infant in the first 48 hours was less in the intermittent flush group with a mean difference of -0.76 cannulas (95% CI -1.37 to -0.15). No results were available for any of our other primary outcomes: in the published report, results were reported per catheter rather than per infant, a number of infants received more than one intravenous catheter (39 infants received an unknown number of catheters). The overall duration of cannula patency was significantly longer in the intermittent flush group with a mean duration of patency in the intermittent flush group of 2.1 days (SD 1.0) compared with the continuous infusion group where the mean duration of patency was 1.0 days (SD 0.5) - Student's t test P value 0.0003. AUTHORS' CONCLUSIONS: It is difficult to draw reliable conclusions given the way the data were analysed and reported in the two included studies. The reliability of the results is uncertain. However, given the caution in interpreting these data, it should also be noted that the use of intermittent flushes was not associated in either study with a decreased cannula life or any other disadvantages, thus lending some support for the use of intermittent flushing of cannulas in a selected population in neonatal nurseries.


Assuntos
Cateterismo Periférico/instrumentação , Infusões Intravenosas/métodos , Irrigação Terapêutica/métodos , Falha de Equipamento , Humanos , Recém-Nascido , Ensaios Clínicos Controlados Aleatórios como Assunto
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