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1.
Eur J Neurosci ; 57(8): 1432-1441, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36932672

RESUMO

The innate immune response plays an important role in the pathological process of ischemic stroke. Increasing evidence suggests that the inflammatory response triggered by the innate immune system hinders neurological and behavioural recovery after stroke. The perception of abnormal DNA and its downstream effects are an essential part of the innate immune system. The abnormal DNA is the major inducing factor for innate immune response and is sensed by a series of DNA sensors. In this review, we discussed the multiple roles of DNA sensing in the pathological process of ischemic stroke, with a special focus on DNA sensors Toll-like receptor 9 (TLR9), absent in melanoma 2 (AIM2) and cyclic GMP-AMP synthase (cGAS).


Assuntos
AVC Isquêmico , Humanos , DNA , Imunidade Inata
2.
J Prev Alzheimers Dis ; 8(2): 161-168, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33569562

RESUMO

BACKGROUND: Although evidence suggests that subjective memory complaints (SMCs) could be a risk factor for dementia, the relationship between SMCs and objective memory performance remains controversial. Old adults with or without mild cognitive impairment (MCI) may represent a highly heterogeneous group, based partly on the demonstrated variability in the level of executive function among those individuals. It is reasonable to speculate that the accuracy of the memory-monitoring ability could be affected by the level of executive function in old adults. OBJECTIVE: This study investigated the effects of executive function level on the consistency between SMCs and objective memory performance while simultaneously considering demographic and clinical variables in nondemented older adults. SETTING: Participants were recruited from both the memory clinics and local communities. PARTICIPANTS: Participants comprised 65 cognitively normal (CN) older adults and 54 patients with MCI. MEASUREMENTS: Discrepancy scores between subjective memory evaluation and objective memory performance were calculated to determine the degree and directionality of the concordance between subjective and objective measures. Demographic, emotional, genetic, and clinical information as well as several executive function measurements were collected. RESULTS: The CN and MCI groups exhibited similar degrees of SMC; however, the patients with MCI were more likely to overestimate their objective memory ability, whereas the CN adults were more likely to underestimate their objective memory ability. The results also revealed that symptoms of depression, group membership, and the executive function level together predicted the discrepancy between the subjective and objective measures of memory function; however, the executive function level retained its unique predictive ability even after the symptoms of depression, group membership, and other factors were controlled for. CONCLUSION: Although both noncognitive and cognitive factors were necessary for consideration, the level of executive function may play a unique role in understanding the equivocal relationship of the concurrence between subjective complaints and objective function measures. Through a comprehensive evaluation, high-risk individuals (i.e., CN individuals heightened self-awareness of memory changes) may possibly be identified or provided with the necessary intervention during stages at which objective cognitive impairment remains clinically unapparent.


Assuntos
Disfunção Cognitiva/psicologia , Demência/psicologia , Depressão/psicologia , Função Executiva/fisiologia , Memória/fisiologia , Idoso , Cognição/fisiologia , Demência/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
3.
Biochemistry (Mosc) ; 85(3): 334-343, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32564738

RESUMO

Obesity and latent inflammation can give rise to insulin resistance and type 2 diabetes. Here we established an insulin resistance model of osteoblasts to explore the restoration effect of anti-inflammatory interleukin-4 (IL-4) on insulin sensitivity and its mechanism. We found that IL-4 inhibited cell proliferation in a concentration- and time-dependent manner. Insulation resistance significantly reduced the phosphorylation levels of the insulin receptor substrate 1 (IRS1; Tyr612), Akt (Ser473), and AS160 (Ser318) proteins. The addition of IL-4 to the insulin resistance model led to a dose-dependent stimulation of the phosphorylation of IRS1, Akt, and AS160. IL-4 fully restored the activation of the insulin cascade in insulin-resistant cells at the concentration of 50 ng/ml. Additionally, IL-4 promoted the expression of IRS1 in a time-dependent manner. We conjecture that IL-4 restores insulin sensitivity in osteoblasts by upregulating the expression of IRS1. It was also found that IL-4 promoted the expression of osteoprotegerin depending on the time of exposure. This effect may play an important role in the regulation of the energy metabolism in the whole body.


Assuntos
Regulação da Expressão Gênica , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina , Insulina/metabolismo , Interleucina-4/metabolismo , Osteoblastos/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Metabolismo Energético , Humanos , Inflamação , Lipídeos/química , Obesidade/metabolismo , Osteoprotegerina/metabolismo , Fosforilação
4.
Ann Oncol ; 24(9): 2382-9, 2013 09.
Artigo em Inglês | MEDLINE | ID: mdl-23788751

RESUMO

BACKGROUND: Combined inhibition of vascular, platelet-derived, and epidermal growth factor receptor (EGFR) pathways may overcome refractoriness to single agents in platinum-pretreated non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: This randomized, double-blind, multicenter, phase II trial evaluated sunitinib 37.5 mg/day plus erlotinib 150 mg/day versus placebo plus erlotinib continuously in 4-week cycles. Eligible patients had histologically confirmed stage IIIB or IV NSCLC previously treated with one or two chemotherapy regimens, including one platinum-based regimen. The primary end point was progression-free survival (PFS) by an independent central review. RESULTS: One hundred and thirty-two patients were randomly assigned, and the median duration of follow-up was 17.7 months. The median PFS was 2.8 versus 2.0 months for the combination versus erlotinib alone (HR 0.898, P = 0.321). The median overall survival (OS) was 8.2 versus 7.6 months (HR 1.066, P = 0.617). Objective response rates (ORRs) were 4.6% and 3.0%, respectively. Sunitinib plus erlotinib was fairly well tolerated although most treatment-related adverse events (AEs) were more frequent than with erlotinib alone: diarrhea (55% versus 33%), rash (41% versus 30%), fatigue (31% versus 25%), decreased appetite (30% versus 13%), nausea (28% versus 14%), and thrombocytopenia (13% versus 0%). CONCLUSIONS: The addition of sunitinib to erlotinib did not significantly improve PFS in patients with advanced, platinum-pretreated NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Indóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Pirróis/uso terapêutico , Quinazolinas/uso terapêutico , Adulto , Idoso , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Intervalo Livre de Doença , Método Duplo-Cego , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib , Feminino , Humanos , Indóis/efeitos adversos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Pirróis/efeitos adversos , Quinazolinas/efeitos adversos , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Sunitinibe , Sobrevida , Resultado do Tratamento
5.
Cancer Chemother Pharmacol ; 69(3): 709-22, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21989766

RESUMO

PURPOSE: The primary objective of this phase I dose-escalation study was to identify the maximum tolerated dose (MTD) of sunitinib plus pemetrexed in patients with advanced cancer. METHODS: Using a 3 + 3 dose-escalation design, patients received oral sunitinib qd by continuous daily dosing (CDD schedule; 37.5 or 50 mg) or 2 weeks on/1 week off treatment schedule (Schedule 2/1; 50 mg). Pemetrexed (300-500 mg/m(2) IV) was administered q3w. At the proposed recommended phase 2 dose (RP2D), additional patients with non-small cell lung cancer (NSCLC) were enrolled. RESULTS: Thirty-five patients were enrolled on the CDD schedule and seven on Schedule 2/1. MTDs were sunitinib 37.5 mg/day (CDD/RP2D) or 50 mg/day (Schedule 2/1) with pemetrexed 500 mg/m(2). Dose-limiting toxicities included grade (G) 5 cerebral hemorrhage, G3 febrile neutropenia, and G3 anorexia. Common G3/4 drug-related non-hematologic adverse events (AEs) at the CDD MTD included fatigue, anorexia, and hand-foot syndrome. G3/4 hematologic AEs included lymphopenia, neutropenia, and thrombocytopenia. No significant drug-drug interactions were identified. Five (24%) NSCLC patients had partial responses. CONCLUSIONS: In patients with advanced solid malignancies, the MTD of sunitinib plus 500 mg/m(2) pemetrexed was 37.5 mg/day (CDD schedule) or 50 mg/day (Schedule 2/1). The CDD schedule MTD was tolerable and demonstrated promising clinical benefit in NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Estudos de Coortes , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Glutamatos/administração & dosagem , Glutamatos/efeitos adversos , Glutamatos/farmacocinética , Glutamatos/uso terapêutico , Guanina/administração & dosagem , Guanina/efeitos adversos , Guanina/análogos & derivados , Guanina/farmacocinética , Guanina/uso terapêutico , Humanos , Indóis/administração & dosagem , Indóis/efeitos adversos , Indóis/farmacocinética , Indóis/uso terapêutico , Neoplasias Pulmonares/metabolismo , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Pemetrexede , Pirróis/administração & dosagem , Pirróis/efeitos adversos , Pirróis/farmacocinética , Pirróis/uso terapêutico , Sunitinibe , Resultado do Tratamento
6.
Br J Cancer ; 101(9): 1543-8, 2009 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-19826424

RESUMO

BACKGROUND: Sunitinib malate (SUTENT) has promising single-agent activity given on Schedule 4/2 (4 weeks on treatment followed by 2 weeks off treatment) in advanced non-small cell lung cancer (NSCLC). METHODS: We examined the activity of sunitinib on a continuous daily dosing (CDD) schedule in an open-label, multicentre phase II study in patients with previously treated, advanced NSCLC. Patients > or =18 years with stage IIIB/IV NSCLC after failure with platinum-based chemotherapy, received sunitinib 37.5 mg per day. The primary end point was objective response rate (ORR). Secondary end points included progression-free survival (PFS), overall survival (OS), 1-year survival rate, and safety. RESULTS: Of 47 patients receiving sunitinib, one patient achieved a confirmed partial response (ORR 2.1% (95% confidence interval (CI) 0.1, 11.3)) and 11 (23.4%) had stable disease (SD) > or =8 weeks. Five patients had SD>6 months. Median PFS was 11.9 weeks (95% CI 8.6, 14.1) and median OS was 37.1 weeks (95% CI 31.1, 69.7). The 1-year survival probability was 38.4% (95% CI 24.2, 52.5). Treatment was generally well tolerated. CONCLUSIONS: The safety profile and time-to-event analyses, albeit relatively low response rate of 2%, suggest single-agent sunitinib on a CDD schedule may be a potential therapeutic agent for patients with advanced, refractory NSCLC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Indóis/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Pirróis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Indóis/efeitos adversos , Indóis/farmacocinética , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Pirróis/efeitos adversos , Pirróis/farmacocinética , Sunitinibe
7.
Clin Genet ; 75(5): 429-39, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19459883

RESUMO

Congenital diaphragmatic hernia (CDH) is a common birth defect for which few causative genes have been identified. Several candidate regions containing genes necessary for normal diaphragm development have been identified, including a 4-5 Mb deleted region at chromosome 1q41-1q42 from which the causative gene(s) has/have not been cloned. We selected the HLX gene from this interval as a candidate gene for CDH, as the Hlx homozygous null mouse has been reported to have diaphragmatic defects and the gene was described as being expressed in the murine diaphragm. We re-sequenced HLX in 119 CDH patients and identified four novel single nucleotide substitutions that predict amino acid changes: p.S12F, p.S18L, p.D173Y and p.A235V. These sequence alterations were all present in patients with isolated CDH, although patients with both isolated CHD and CDH with additional anomalies were studied. The single-nucleotide substitutions were absent in more than 186 control chromosomes. In-situ hybridization studies confirmed expression of Hlx in the developing murine diaphragm at the site of the junction of the diaphragm and the liver. Although functional studies to determine if these novel sequence variants altered the inductive activity of Hlx on the alpha-smooth muscle actin and SM22alpha promoters showed no significant differences between the variants and wild-type Hlx, sequence variants in HLX may still be relevant in the pathogenesis of CDH in combination with additional genetic and environmental factors.


Assuntos
Cromossomos Humanos Par 1/genética , Variação Genética , Hérnia Diafragmática/genética , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Animais , Sequência de Bases , Embrião de Mamíferos , Humanos , Hibridização In Situ , Cariotipagem , Camundongos , Dados de Sequência Molecular , Fenótipo , Análise de Sequência de DNA
8.
J Asian Nat Prod Res ; 10(1-2): 105-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18253877

RESUMO

A new indole alkaloid, named donasine, has been isolated from the rhizomes of Arundo donax L. Its structure was determined by X-ray crystallographic analysis and spectral methods. The primary pharmacological test showed that the compound has an action of reducing fever.


Assuntos
Alcaloides Indólicos/química , Poaceae/química , Modelos Moleculares , Estrutura Molecular
9.
J Appl Microbiol ; 102(3): 872-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17309638

RESUMO

AIMS: To determine the identity and composition of mesophilic Bacillus spp. in faeces sampled from feedlot cattle. METHODS AND RESULTS: Faecal samples from 10 feedlot cattle were analysed. The total aerobic spore count increased from 4.6 x 10(4) CFU g(-1) (before feedlotting, day 0) to 1.6 x 10(6) CFU g(-1) (feedlot for day 76). A total of 150 randomly selected spore isolates (60 each from days 0 and 76 cattle, 30 from feed) were speciated using a Bacillus group-specific PCR-amplified ribosomal DNA restriction analysis technique (Wu et al. 2006). At day 0, Bacillus subtilis and Bacillus cereus predominated with a prevalence of 58.3% and 26.7%, respectively, whereas three species, B. subtilis (50.0%), Bacillus licheniformis (27.6%) and Bacillus clausii (20.0%) predominated in day 76 faecal samples. Of these, only the first two species were present in feed samples at a frequency of 70% and 30% respectively. All B. cereus isolates on day 0, possessed at least one of three enterotoxin genes (nheA, nheB and nheC) but these were completely eliminated after a period of feedlotting. All isolates of B. licheniformis were genotypically heterogeneous according to pulsed-field gel electrophoresis analysis. CONCLUSIONS: Cattle faeces contain large numbers of Bacillus spores representing different mesophilic species. Stable faecal populations of particular Bacillus spp. mimicking those found in feed, were subsequently established by feedlotting. SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained and methods used in this study will help to investigate the indigenous Bacillus composition in the gastrointestinal tract of cattle and will further guide the administration of Bacillus probiotics.


Assuntos
Bacillus/isolamento & purificação , Fezes/microbiologia , Animais , Bacillus/genética , Bacillus cereus/genética , Bacillus cereus/isolamento & purificação , Bacillus subtilis/genética , Bacillus subtilis/isolamento & purificação , Bovinos , Contagem de Colônia Microbiana/métodos , DNA Bacteriano/genética , DNA Ribossômico/genética , Eletroforese em Gel de Campo Pulsado/métodos , Enterotoxinas/genética , Genes Bacterianos/genética , Mapeamento por Restrição/métodos , Esporos Bacterianos/genética , Esporos Bacterianos/isolamento & purificação
11.
J Urol ; 166(4): 1354-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11547073

RESUMO

PURPOSE: We evaluated the use of collagen in women with stress urinary incontinence and urethral hypermobility. MATERIALS AND METHODS: We treated 90 patients with stress urinary incontinence and urethral hypermobility with 1 to 3 injections of Contigen implant (C. R. Bard, Inc., Covington, Georgia) between June 1996 and October 1998. Observations at 3, 6 and 12 months included continence grade, 7-day voiding diaries and quality of life questionnaires. Abdominal leak point pressure was determined at baseline and 12 months. RESULTS: At the 6-month followup 68 patients remained in the study, of whom 30 (44%) were dry and 24 (35%) were improved. Of the 58 patients who reached the 12-month followup 19 (33%) were dry and 19 (33%) were improved. Considering all patients entered into the study at 6 months 30 (33%) were dry and 24 (27%) were improved. Of the original 90 patients 19 (21%) were dry and 19 (21%) were improved at 12 months. The probability of maintaining initial improvement for 12 months was 44%. The success of bulking agent therapy was not predicted by the initial incontinence grade. Improved continence grade correlated with improved leak point pressure. CONCLUSIONS: This therapy is appropriate in women with urethral hypermobility who wish to avoid surgical risks and in those in whom surgery is ill advised.


Assuntos
Colágeno , Próteses e Implantes , Doenças Uretrais/complicações , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Plast Reconstr Surg ; 108(2): 386-91, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11496180

RESUMO

In the clinical management of combined tendon and nerve injuries, there are competing treatment strategies. Isolated tendon injuries should be rapidly mobilized after repair to prevent adhesion formation, whereas isolated nerve repairs are usually immobilized to prevent disruption and to allow axon regrowth. Recommendations in the published literature for the management of combined tendon and nerve injuries are vague and advise up to 3 weeks of immobilization. The goals of this study were to determine which length of nerve gap resulted in rupture of a repair following postoperative mobilization with the modified Duran protocol and with unrestricted motion and to determine whether nerve grafts are at risk of rupture after mobilization. A total of 100 digital nerves from 10 cadaver hands were tested with the modified Duran and the unsplinted protocols. Each digital nerve on each hand was sequentially resected and repaired at five progressively larger gap lengths after testing with both protocols. The mean nerve gaps at which disruption occurred were significantly different between the splinted (9.7 +/- 0.8 mm, n = 100) and unsplinted (7.3 +/- 1.9 mm, n = 100) protocols (t test, p < 0.001). One hundred percent of repairs remained intact, with up to 5 mm of resection with the modified Duran protocol (n = 100) and with up to 2.5 mm of resection with the unsplinted protocol (n = 100). All nerve grafts remained intact after mobilization within a dorsal-blocking splint (n = 100). Considering mechanical integrity of the nerve repair only, these data suggest that early mobilization with tendon protocols may be considered after a nerve injury to avoid the detrimental tendon sequelae that result from immobilization. The adequacy of functional recovery of mobilized nerves is yet to be determined.


Assuntos
Dedos/inervação , Terapia Passiva Contínua de Movimento , Nervos Periféricos/cirurgia , Cadáver , Traumatismos dos Dedos/reabilitação , Traumatismos dos Dedos/cirurgia , Humanos , Imobilização , Técnicas In Vitro , Terapia Passiva Contínua de Movimento/efeitos adversos , Nervos Periféricos/fisiopatologia , Nervos Periféricos/transplante , Cuidados Pós-Operatórios , Ruptura , Estresse Mecânico , Tendões/cirurgia
13.
Child Dev ; 72(6): 1832-43, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11768148

RESUMO

This study examined the effects of parent-adolescent relationships on school performance to provide a clearer understanding of why authoritative parenting does not have as beneficial effects for Asian Americans as it does for European Americans. Over 500 adolescents of Chinese- (148 first and 176 second generation) and European-descent (208 primarily third generation or more) families from seven different high schools completed measures of (1) parenting style, (2) parent-adolescent closeness (cohesion subscale from the Family Adaptability and Cohesion Environment Scales II and relationship satisfaction), and (3) school performance. Positive effects of both authoritative parenting and relationship closeness on school performance were found for European Americans and, to some extent, second-generation Chinese, but not first-generation Chinese. These effects were also stronger for European Americans than first-generation Chinese. Through examination of the mediating role of parent-adolescent relationships, this study also found that among European American families, the beneficial effects of authoritative parenting are explained through relationship closeness.


Assuntos
Relações Interpessoais , Relações Pais-Filho , Poder Familiar , China/etnologia , Europa (Continente)/etnologia , Feminino , Humanos , Masculino , Estados Unidos/epidemiologia
14.
Ann Thorac Surg ; 70(1): 264-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10921720

RESUMO

BACKGROUND: Lung transplantation requires a period of storage and ischemia; we examined the largely unknown effects of that period on intermediary metabolism. METHODS: Two groups of isolated rat lung blocks (n = 16 each) were flushed with Euro-Collins solution and harvested. The lung blocks were immediately ventilated and either perfused for 30 minutes with an erythrocyte-based solution containing carbon 13 labeled substrates (group 1) or stored for 6 hours at 1 degree C and then reperfused (group 2). Half of each group was reperfused at a physiologic Po2 the other half at high Po2. Analysis of carbon 13 isotopomers was performed to determine substrate utilization through aerobic pathways in lung tissue. RESULTS: Lungs from both groups oxidized all major substrates. The contribution of fatty acids to acetylcoenzyme acid oxidized in the citric acid cycle was significantly higher in group 2 than in group 1 (31.3% +/- 2.2% versus 22.0% +/- 2.1%, p < 0.05). Perfusate Po2 did not affect substrate preference. Gas exchange was worse in stored lungs. CONCLUSIONS: After a period of hypothermic ischemia and storage, substrate preference in lung tissue exhibits a switch towards fatty acids. As fatty acid oxidation occurring after ischemia is deleterious in other organs, strategies to inhibit this process in stored lungs may warrant further investigation.


Assuntos
Precondicionamento Isquêmico , Transplante de Pulmão , Pulmão/metabolismo , Preservação de Órgãos , Oxigênio/administração & dosagem , Reperfusão , Animais , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 55A(11): 2261-70, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10581737

RESUMO

Infrared and Raman spectra have been obtained for lyophilized recombinant bovine growth hormone (r-bGH), partially reduced, and completely reduced r-bGH, plus a tryptic digest fragment of r-bGH. Amide I and II data indicate r-bGH to have substantial helical character. Partially reduced r-bGH, in which the carboxyl terminal disulfide bridge (residues 181, 189) has been cleaved, has slightly less helical content than r-bGH. The spectral data indicate that breaking the carboxyl terminal cystine link produces only localized structural alterations. The additional cleavage of the second disulfide bridge (residues 53,164) leads to a further decrease in helix content, accompanied by increases in beta-sheet and disordered structures. A tryptic digest r-bGH fragment (residues 96-133), which contains a small amount of biological activity (approximately 10%), has predominantly helical structure.


Assuntos
Hormônio do Crescimento/química , Hormônios/química , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Animais , Bovinos , Dissulfetos , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Proteínas Recombinantes de Fusão/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Tripsina
16.
J Biomater Sci Polym Ed ; 10(2): 235-46, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10091933

RESUMO

We employed gamma scintigraphy to quantify the transient accumulations of platelets in pump-oxygenator systems employed in cardiopulmonary bypass (CPB). A flat sheet microporous polypropylene membrane oxygenator (Cobe Duo) was employed, with and without siloxane/caprolactone oligomer coating (SMA) (n = 8 each). The effect of nitric oxide gas infusion on platelet deposition was also evaluated for the uncoated Cobe Duo system (n = 10 each). Scintigraphic images of radiolabelled cells were obtained and converted to numbers of all platelets, labeled and unlabeled, adhering to the pump and oxygenator surfaces. These numbers were compared, by study group, for a 90-min period of normothermic CPB in the adult pig, employing standard prime and anticoagulation regimens. Platelets adhered in large numbers to control oxygenators, reaching maxima (> 20% of the circulating platelet mass) 30 min following institution of CPB, and decreasing for the duration of CPB. SMA treatment significantly decreased platelet adhesion following a 5-10-min transient accumulation period. Nitric oxide infusion significantly reduced platelet adhesion throughout the CPB period. Platelet accumulations on the high fluid shear centrifugal pump surfaces increased monotonically to maxima at about the same time as for the oxygenators, but did not decrease thereafter. Higher platelet surface densities were observed on the centrifugal pump surfaces than on the oxygenator surfaces. CPB with the untreated circuit tended to reduce circulating platelet counts vs theoretical values based on hemodilution alone. In contrast, SMA significantly increased the circulating platelet count versus the untreated control group. These results indicate that platelet adherence to the foreign surfaces of CPB equipment are influenced in characteristic ways by time and fluid shear. SMA treatment and nitric oxide infusion both reduce platelet adhesion to oxygenator surfaces. SMA treatment spares these cells for the circulation.


Assuntos
Plaquetas/metabolismo , Adesão Celular , Oxigenadores/efeitos adversos , Polímeros/metabolismo , Animais , Hematócrito , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico/uso terapêutico , Polipropilenos/metabolismo , Siloxanas/metabolismo , Siloxanas/uso terapêutico , Suínos , Fatores de Tempo
17.
Pharm Res ; 16(12): 1850-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10644073

RESUMO

PURPOSE: To investigate the cause for decrease in delavirdine mesylate 200 mg tablet dissolution upon exposure to high humidity. METHODS: Dissolution testing was performed using the USP 2 (paddle) apparatus. Water in tablets was measured by Karl Fischer titration. 13C CP/MAS NMR was used to identify and quantify delavirdine form changes in tablets. FT-IR spectroscopy was used to monitor delavirdine form change in tablets and component mixes, and to investigate a solid state reaction with the disintegrant. RESULTS: Dissolution extent of delavirdine mesylate 200 mg tablets was substantially decreased after exposure to high humidity. This effect is related to the amount of water present in the tablet matrix. 13C CP/ MAS NMR detected about 30% conversion from the mesylate salt of delavirdine to its free base form in the tablet matrix. FT-IR spectroscopy demonstrated that a solid state reaction occurs between the freed methanesulfonic acid and the carboxyl sites on the croscarmellose sodium disintegrant. CONCLUSIONS: Water is thought to act as both a reaction medium and a plasticizer for croscarmellose sodium, facilitating protonation of the carboxyl sites on the disintegrant. This reaction has the potential to occur for any acid salt of a free base. The limiting solubility of delavirdine free base formed in the tablets accounts for much of the decrease in the extent of dissolution. A change in inter-particle bonding can explain the reduction in tablet deaggregation during dissolution.


Assuntos
Delavirdina/química , Excipientes/química , Comprimidos , Carboximetilcelulose Sódica/química , Delavirdina/administração & dosagem , Estabilidade de Medicamentos , Espectroscopia de Ressonância Magnética , Solubilidade , Espectrofotometria Infravermelho , Água/análise
18.
ASAIO J ; 43(5): M739-44, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9360144

RESUMO

The authors employed gamma scintigraphy to quantify the post bypass accumulations of platelets and neutrophils in the lung, liver, and heart of adult pigs subjected to a standard 90 min regimen of normothermic cardiopulmonary bypass (CPB). Coated and uncoated microporous polypropylene oxygenator circuits were studied for Cobe Duo (Arvada, CO) oxygenators (amphophilic silicone-caprolactone oligomer [SMA] coating, n = 8 each) and Medtronic Maxima (Irvine, CA) oxygenators (Carmeda heparin coating, n = 5 each). Images of cells in the organs (deposited + blood pool) were corrected for tissue absorption and other factors and compared for a 2 hr period post CPB, using repeat measures ANOVA and rank tests. Platelet accumulations in internal organs correlated positively with whole blood platelet counts and negatively with platelet deposits in oxygenators during CPB. In general, uncoated CPB circuits significantly reduced platelet and neutrophil accumulations in lung, liver, and heart versus preCPB controls for the post CPB interval, for both systems. The SMA treatment significantly increased platelet accumulations versus uncoated controls in lung, liver, and heart for the 2 hr period, including the majority of the post CPB sampling intervals; platelet densities did not reach preCPB levels. Neutrophil accumulations were unaffected by the SMA coating. Carmeda heparin treatment significantly increased platelet accumulations in the liver, but not lung or heart. Despite preservation of circulating neutrophils observed with the Carmeda heparin treatment, neutrophil accumulations in internal organs were not elevated post CPB.


Assuntos
Plaquetas/fisiologia , Ponte Cardiopulmonar/efeitos adversos , Neutrófilos/patologia , Animais , Plaquetas/diagnóstico por imagem , Plaquetas/patologia , Ponte Cardiopulmonar/instrumentação , Adesão Celular , Movimento Celular , Estudos de Avaliação como Assunto , Câmaras gama , Coração/diagnóstico por imagem , Hemodiluição/efeitos adversos , Radioisótopos de Índio , Fígado/diagnóstico por imagem , Fígado/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Miocárdio/patologia , Neutrófilos/diagnóstico por imagem , Especificidade de Órgãos , Adesividade Plaquetária , Polipropilenos , Cintilografia , Suínos
19.
Zhongguo Zhong Yao Za Zhi ; 22(4): 233-4, 255, 1997 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-10743217

RESUMO

A reversed-phase HPLC method was developed for the determination of maesopsin, a fliavonoid, in the xylem parts of the traditional Tibetan medicinal herb Shengdeng (Rhamnella gilgitica). An ODS column was used and the mobile phase was methanol-water (28:27) with 0.05 mol/L KH2PO4 (pH4). The detection wavelength was UV 290 nm. The recovery was 98.9% (RSD = 2.1%, n = 6) and the content of maesopsin in Shengdeng was 1.02% (RSD = 0.52%, n = 3).


Assuntos
Benzofuranos/análise , Medicamentos de Ervas Chinesas/química , Plantas Medicinais/química , Rosales/química , Cromatografia Líquida de Alta Pressão/métodos
20.
Hua Xi Yi Ke Da Xue Xue Bao ; 28(1): 37-9, 1997 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-10684059

RESUMO

In this study the asexual cell line H292 induced and selected from Coptis gulinensis had rapid growth rate and could stably produce alkaloids. By the one-stage method, after the cell suspensions were cultured on the same medium for six weeks, the increased dry and fresh weights of the cells were 20.96 g/L and 174.92 g/L respectively. The content of the total alkaloids in the cells was 14.79 mg/g cell dw. Per litter liquid medium could provide 323 mg alkaloid. In contrast, the cells were cultured by two-stage method. After having been cultured on the medium which contributed to the growth of the cells for three weeks, the cells were transferred to the medium which contributed to the production of the alkaloid and cultured for three weeks. Six weeks later, the dry and fresh weights of the cells were 16.72 g/L and 127.44 g/L, respectively. The biomass was lower than that by one-stage method, but the content of the total alkaloids was as high as 31.76 mg/g cell dw, which was much more than that by one-stage method. In addition, the content of the alkaloid in the medium was 25.31 mg/L. Per litter liquid medium could provide 556 mg alkaloid. The total yield of alkaloid obtained by two-stage method was 1.72 times than that by one-stage method.


Assuntos
Magnoliopsida/citologia , Plantas Medicinais/citologia , Alcaloides/análise , Técnicas de Cultura de Células/métodos , Células Cultivadas , Magnoliopsida/química , Plantas Medicinais/química
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