RESUMO
A new method for purifying human interferon-beta SER17 from E. coli-derived inclusion bodies has been developed. This procedure eliminates the need for strong denaturants, such as sodium dodecyl sulfate or chaotropes. The procedure makes use of a nondenaturing detergent and a brief incubation at pH 12 to solubilize interferon-beta Ser17 from inclusion bodies. The detergent used was Zwittergent 3-14 (nonionic and pH-insensitive), which is included in the class of sulfobetaines (RN+ (CH3)2(CH2)xSO3-). Zwittergent 3-14 was used in combination with urea to produce a urea/Zwittergent 3-14 washed inclusion body preparation enriched in human interferon-beta Ser17 (Betaseron). Solubilization of inclusion bodies was accomplished by employing a brief (1 minute) shift to pH 12 in the presence of 2.5% Zwittergent 3-14 followed by rapid adjustment to pH 8.0. Solubilization was complete, and the solution could be rapidly adjusted to pH 8 without any observable precipitation of protein. The resultant supernatant could be successfully subjected to a number of chromatographic and analytic procedures, many of which are not compatible with strong anionic detergents, such as SDS. Betaseron was purified from Zwittergent 3-14 solubilized inclusion body lysates using both ion-exchange and size-exclusion chromatography. Purified Betaseron retained bioactivity and could be refolded by simple dialysis against a nonreducing buffer. This method represents a novel procedure for purifying Betaseron from inclusion bodies using a nondenaturing detergent and ion-exchange chromatography.
Assuntos
Detergentes , Corpos de Inclusão/química , Interferon beta/isolamento & purificação , Compostos de Amônio Quaternário/farmacologia , Escherichia coli , Humanos , Interferon beta-1a , Interferon beta-1b , Dobramento de Proteína , Proteínas Recombinantes/isolamento & purificação , SolubilidadeRESUMO
Although metformin has been used worldwide to treat type 2 diabetes for several decades, its mechanism of action on glucose homeostasis remains controversial. To further assess the effect of metformin on glucose metabolism, 10 42-hour-fasted conscious dogs were studied in the absence ([Con] n = 5) and presence ([Met] n = 5) of a portal infusion of metformin (0.15 mg x kg(-1) x min(-1)) over 300 minutes. Hepatic glucose production was measured by both arteriovenous-difference and tracer methods. All dogs were maintained on a pancreatic clamp and in a euglycemic state to ensure that any changes in glucose metabolism would result directly from the effects of metformin. The arterial metformin level was 21 +/- 3 microg/mL during the test period. Net hepatic glucose output (NHGO) decreased in Met dogs from 1.9 +/- 0.2 to 0.7 +/- 0.1 mg x kg(-1) x min(-1) (P < .05). NHGO remained unchanged in Con dogs (1.7 +/- 0.3 to 1.5 +/- 0.3 mg x kg(-1)min(-1)). Tracer-determined glucose production paralleled NHGO. The net hepatic glycogenolytic rate decreased from 1.0 +/- 0.2 to -0.3 +/- 0.2 mg x kg(-1) x min(-1) (P < .05) in Met dogs, but remained unchanged in Con dogs (0.8 +/- 0.2 to 0.8 +/- 0.3 mg x kg(-1) x min(-1)). No significant change in gluconeogenic flux was found in eitherthe Metgroup (1.2 +/- 0.3 to 1.3 +/- 0.3 mg x kg(-1) x min(-1)) or the Con group (1.3 +/- 0.4 to 1.0 +/- 0.3 mg x kg(-1) x min(-1)). No significant changes were observed in glucose utilization or glucose clearance in either group. In conclusion, in the normal fasted dog, (1) the primary acute effect of metformin on glucose metabolism was an inhibition of hepatic glucose production and not a stimulation of glucose utilization; and (2) the inhibition of glucose production was attributable to a decrease in hepatic glycogenolysis and not to an alteration in gluconeogenic flux.
Assuntos
Glucose/biossíntese , Glicogênio/metabolismo , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Ácido 3-Hidroxibutírico/sangue , Ácido 3-Hidroxibutírico/metabolismo , Acetoacetatos/sangue , Acetoacetatos/metabolismo , Alanina/metabolismo , Animais , Artérias , Cães , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Feminino , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Glicerol/sangue , Glicerol/metabolismo , Cinética , Ácido Láctico/metabolismo , Fígado/metabolismo , Masculino , Plasma , Fatores de TempoRESUMO
The novel peptide feglymycin has been isolated from cultures of Streptomyces sp. DSM 11171 by solid phase extraction, size exclusion chromatography and repeated reversed-phase chromatography. The molecular weight was found to be 1900.90 g/mol and the molecular formula is C95H97Nl3O30. Feglymycin contains 13 amino acids of which four are 3-hydroxyphenylglycine and five are 3,5-dihydroxyphenylglycine residues. The structure of the linear peptide has been determined by 1H and 13C NMR spectroscopy. The sequence was confirmed by the observed mass spectroscopic fragmentation pattern. As well as having weak antibacterial activity, feglymycin inhibits the replication of the human immunodeficiency virus (HIV) in vitro.
Assuntos
Antivirais/isolamento & purificação , HIV/efeitos dos fármacos , Peptídeos/isolamento & purificação , Proteínas/isolamento & purificação , Streptomyces/química , Replicação Viral/efeitos dos fármacos , Antivirais/química , Antivirais/farmacologia , Cromatografia em Gel , Escherichia coli/efeitos dos fármacos , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Células Gigantes/efeitos dos fármacos , HIV/fisiologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Peso Molecular , Peptídeos/química , Peptídeos/farmacologia , Proteínas/química , Proteínas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Streptomyces/metabolismoRESUMO
Two novel compounds, kodaistatin A, C35H34O11, molecular weight 630, and kodaistatin C, C35H34O12, molecular weight 646, have been isolated from cultures of Aspergillus terreus Thom DSM 11247 by solid-phase extraction, size-exclusion chromatography, and various preparative HPLC steps. The use of a range of 2D NMR measurements, in particular 13C-13C correlation measurements, has led to the clarification of the structure of kodaistatin A. Kodaistatin C is a hydroxylated derivative of kodaistatin A. Both natural products contain hydroxylated aspulvinones and identical highly substituted polyketide units. An X-ray single crystal structure analysis of aspulvinon E demonstrated the z-configuration at the central double bond. The kodaistatins are effective inhibitors of the glucose-6-phosphate translocase component of the glucose-6-phosphatase system (EC 3.1.3.9), an enzyme system which is important for the control of blood glucose levels. The IC50 is 80 nM for kodaistatin A and 130 nM for kodaistatin C.
Assuntos
Aspergillus/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fosfotransferases/antagonistas & inibidores , Animais , Antiporters , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/enzimologia , Inibidores Enzimáticos/isolamento & purificação , Concentração Inibidora 50 , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Estrutura Molecular , Proteínas de Transporte de Monossacarídeos , RatosRESUMO
The new pluramycin-type antibiotics pluraflavin A, C43H54N2O14, pluraflavin B, C43H56N2O15, and pluraflavin E, C36H41NO14 were isolated from cultures of the Saccharothrix species DSM 12931. The structures of the novel compounds were elucidated with the aid of 2D NMR and mass spectrometric investigations. The characteristic structural element of pluraflavins A and B is an additional 4-epi-vancosamine unit at position 13 of the anthraquinone-gamma-pyrone ring system. Pluraflavin E has a carboxyl group in this position. Pluraflavin A has a reactive dimethyl epoxide side chain at position 2 of the anthraquinone-gamma-pyrone aglycon, which may explain the high activity of the antibiotic. The outstanding biological characteristic of pluraflavin A is its powerful, organ-dependent cytostatic action: the IC50 in the colon carcinoma proliferation assay is in the subnanomolar range.
Assuntos
Actinomycetales/metabolismo , Antraquinonas/isolamento & purificação , Antraquinonas/metabolismo , Antraquinonas/farmacologia , Antibióticos Antineoplásicos/biossíntese , Antibióticos Antineoplásicos/isolamento & purificação , Divisão Celular/efeitos dos fármacos , Actinomycetales/crescimento & desenvolvimento , Antraquinonas/química , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Meios de Cultura , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Estrutura Molecular , Células Tumorais CultivadasRESUMO
New antifungal antibiotics, designated as 3874 H1 and H3, were discovered in the fermentation broth of the strain Streptomyces sp. HAG 003874. The compounds were obtained as yellow powders after sequential purification by chromatography on MCI Gel CHP20P, Fractogel HW-40 and ODS reversed phase chromatography. On the basis of the results of spectroscopic analysis, it was found that 3874 H1, C58H86N2O18, MW 1098, belongs to the p-aminoacetophenone containing family of heptaene antibiotics, while 3874 H3, C57H87NO18, MW 1073, is a non-aromatic heptaene. In addition to these, a minor component, 3874 H2, C59H88N2O18, MW 1112, a N-methyl derivative of 3874 H1 has been detected. The structures were elucidated through mass spectral analyses and 1-D and 2-D homonuclear and heteronuclear NMR data. The outstanding physico-chemical feature of 3874 H3 is its improved solubility. The new heptaenes are potent antifungal compounds with broad activity spectra, encompassing dermatophytes, yeasts and filamentous fungi.
Assuntos
Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Macrolídeos , Polienos/isolamento & purificação , Streptomyces/química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Contagem de Colônia Microbiana , Fungos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Polienos/química , Polienos/farmacologia , Streptomyces/classificaçãoRESUMO
Many new products designed to assist in rapid blood infusion are appearing. Some highly touted and routinely used devices for intravenous (IV) infusion have recently been shown to be, at least in part, defective. A tubing with an in-line 150 mu filter (150 mu High-Flow Blood Filter; Saftifilter Blood Administration Sets; Cutter Biological, Berkeley, CA 94710) has recently been introduced to facilitate rapid blood transfusion. It is claimed that at least 8.5 units of blood can be rapidly run through each set before replacement is necessary. To test this under simulated clinical conditions, four sets of ten random units of outdated erythrocytes at 4 to 9 degrees C were each admixed with 250 mL 70 degrees C 0.9 NaCl and infused through the system under a constant 300 mmHg pressure. Two sets infused through unmodified tubing flowed at an average of 25 mL/sec (1500 mL/min) before there was an appreciable slowing of the flow rate. Two sets with 8 Fr catheters attached infused at an average of 22 mL/sec (1320 mL/min) before there was an appreciable slowing of the flow rate. Even after the flow slowed, the 9th and 10th units infused at an average greater than 10 mL/sec (600 mL/min). The tubing/filter exceeded the manufacturer's published claims. This tubing/filter appears to be one element that could be an effective component of a high-flow infusion system.
Assuntos
Transfusão de Sangue/instrumentação , Transfusão de Sangue/métodos , Desenho de Equipamento , Filtração , Infusões Intravenosas , Reologia , Fatores de TempoRESUMO
Resuscitation with fluid and blood components is the mainstay of therapy for hypovolemic patients. This study evaluated the flow rate and resultant temperature of 6 degrees C erythrocytes admixed with warmed saline passing through a new commercial large bore tubing. The tubing is 183 cm long and is 0.57 cm in diameter. The effect on the outflow fluid temperature when catheters of various sizes were added to the system distally was also assessed. The admixed solution temperature averaged 36.2 degrees C and the outflow temperature of the mixture from the distal tubing averaged 34.9 degrees C. There was an average drop in temperature over the length of the tube of 1.5 degrees C. The filter in the Medex Hi-Flow Trauma Quad system collapsed, severely restricting fluid flow, after only four units. The problem of filter clogging was overcome by the in-line addition of a Pall filter. Addition of this in-line filter had a negligible effect on the flow rate. The flow rate with the Pall filter in-line averaged 1,150 mL/min. As the catheters that were added distally to the system diminished in size, there was a predictable decrease in the admixed fluid flow rate. A warmed saline-erythrocyte solution may be very rapidly infused through commercial large-bore tubing modified with an in-line filter. The size of the catheters used determines the ultimate flow rate.
Assuntos
Transfusão de Sangue/instrumentação , Transfusão de Eritrócitos , Filtração/instrumentação , Hidratação/instrumentação , Reologia , Humanos , Técnicas In Vitro , Infusões Intravenosas/instrumentação , Cloreto de Sódio/administração & dosagemRESUMO
Our method of percutaneous transhepatic cholangiodrainage (PTCD) and radiotherapy shows better results and prognosis in patients with inoperable tumors of the liver, biliary system and pancreas. PTCD was performed in patients with progressive obstructive jaundice due to inoperable tumors to decompress the hepatobiliary system and to reduce jaundice. This was combined with radiotherapy which was performed pre- and postoperatively and without operation. Aim of radiotherapy was to reduce the tumor and also to explore the possibility of radical operation. Radiotherapy was carried out in most patients with Linear accelerator (Linac), and in some with Betatron or Telecobalt 60. In a few cases was chosen: 1) two phase radiotherapy 2) and/or a combination of ray therapies. Inoperable tumors, which can not be excised, should be treated intraoperatively with radiation therapy. Only after a radiation with 3000-4000 rad linac, tumors showed shrinkage in size and at the same microscopic degenerative changes in tumor cells were observed.
Assuntos
Adenocarcinoma/radioterapia , Neoplasias dos Ductos Biliares/radioterapia , Colestase Intra-Hepática/radioterapia , Cuidados Paliativos , Adenocarcinoma/secundário , Adulto , Idoso , Neoplasias dos Ductos Biliares/secundário , Colangiopancreatografia Retrógrada Endoscópica , Drenagem/métodos , Feminino , Humanos , Jejuno/cirurgia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Dosagem RadioterapêuticaRESUMO
Stress-fractures most often affect healthy bones, in the majority of cases the tibia. We report a case of a young man who had a stress-fracture 18 months after osteosynthesis of a lower leg-fracture. Under biomechanical aspects an oscillation-fracture is mostly probable because the angle of the fracture is exactly 45 degrees to the longitudinal axis of the tibia.
Assuntos
Fixação Interna de Fraturas , Fraturas de Estresse/etiologia , Fraturas da Tíbia/cirurgia , Adulto , Fenômenos Biomecânicos , Fraturas de Estresse/diagnóstico por imagem , Humanos , Masculino , Radiografia , Fraturas da Tíbia/diagnóstico por imagem , Anormalidade TorcionalRESUMO
BACKGROUND: Little is known about the effects of isometric exercise on temporal summation of heat pain. Thus, the purposes of study 1 and study 2 were to examine the influence of exhaustive and non-exhaustive isometric exercise on temporal summation of heat pain in men and women. METHODS: Forty-four men and 44 women (mean age = 20 years) completed an informed consent document and a packet of questionnaires. Ten heat pulses were applied to the thenar eminence of the dominant hand using a standardized temporal summation protocol. Participants rated the intensity of the heat pulses using a 0-100 pain rating scale before and following isometric exercise consisting of squeezing a hand dynamometer at 40% of maximal voluntary contraction (MVC) to exhaustion (exhaustive exercise, study 1) and at 25% MVC for 3 min (non-exhaustive exercise, study 2). Muscle pain and perceived exertion were rated every 30 s during exercise using validated rating scales. The data were analysed with repeated measures analysis of variance. RESULTS: The results indicated there were no sex differences (p > 0.05) in time to exhaustion (study 1), muscle pain or perceived exertion (studies 1 and 2). There was a significant reduction (p < 0.05) in temporal summation ratings following isometric exercise for men and women in both study 1 and study 2. CONCLUSION: It is concluded that exhaustive and non-exhaustive isometric exercise significantly reduced temporal summation of heat pain in men and women.
Assuntos
Exercício Físico/fisiologia , Temperatura Alta/efeitos adversos , Contração Isométrica/fisiologia , Dor/fisiopatologia , Caracteres Sexuais , Adolescente , Adulto , Feminino , Mãos/fisiologia , Humanos , Masculino , Músculo Esquelético/fisiologia , Medição da Dor/métodos , Limiar da Dor/fisiologia , Adulto JovemAssuntos
Fístula Biliar/cirurgia , Colelitíase/cirurgia , Fístula Intestinal/cirurgia , Obstrução Intestinal/cirurgia , Adulto , Idoso , Fístula Biliar/diagnóstico , Colecistectomia , Colelitíase/diagnóstico , Diagnóstico Diferencial , Humanos , Fístula Intestinal/diagnóstico , Obstrução Intestinal/diagnóstico , Masculino , Pessoa de Meia-IdadeAssuntos
Hipertensão Pulmonar/diagnóstico , Pré-Escolar , Diagnóstico Diferencial , Humanos , Masculino , PrognósticoRESUMO
Primary treatment of soft tissue hand injuries is most important for further management and progress. It ensures best protection of lower structures. Soft tissue lesions that can not be closed without resulting tensions need instant plastic-surgical therapy. Various possibilities that range from split skin flaps to distant flaps with microvascular anastomosis can be chosen to cover primary as well as secondary soft tissue defects.
Assuntos
Traumatismos da Mão/cirurgia , Transplante de Pele/métodos , Retalhos Cirúrgicos/métodos , Humanos , Microcirurgia/métodos , Técnicas de SuturaRESUMO
Intraarticular heelbone fractures lead to cartilage damage by way of joint surface incongruence. This causes arthrosis of the lower ankle joint. The influence of a dislocated calcaneus fracture on the upper ankle joint was documented in an experimental study on eight cadaver legs. We performed an osteotomy of the calcaneus to imitate a typical fracture, placed a pressure film into the upper ankle joint and subjected the joint to axial pressure of 850 N. Changes in contact area and pressure pattern were measured in different flexion/extension positions of the foot. Results with respect to total contact area and high-pressure contact zone are discussed.
Assuntos
Articulação do Tornozelo/fisiopatologia , Calcâneo/lesões , Fraturas Ósseas/fisiopatologia , Fenômenos Biomecânicos , Humanos , PressãoRESUMO
The technique of rapid admixture blood warming of cold erythrocyte units is designed to warm erythrocyte units rapidly (less than 30 sec) while simultaneously providing saline for dilution. However, questions have been raised about the recommended use of a standard 250-ml bolus of 70 degrees C admixture saline, the uniformity and speed of blood unit warming, the difficulties inherent in keeping saline bags at 70 degrees C, and the safety of the methodology. To answer these questions, a series of tests were performed and modifications of the technique were introduced. The mean weight of 1000 successive units of erythrocytes for adult infusion was 305 g (range 220 to 410). The maximum temperature was 44 degrees C, using an internal temperature probe (1-cm temperature gradations; 2-sec recording intervals) when the smallest unit was admixed with a 250 ml 70 degrees C saline bolus; the largest unit had a minimum temperature of 30 degrees C. Plasma Hgb, osmotic fragility, and K of the minimum size erythrocyte unit showed no significant deviation from its control. Both thermographic photographs and the internal temperature recordings of the erythrocyte units demonstrated that solely due to fluid turbulence, uniform mixing occurs within approximately 30 sec of beginning the admixture process. Inverting the blood units caused a thermal layering of fluids and an unacceptable maximum blood temperature of 50 degrees C. There was no difference between the mixing time or efficacy in the presence of standard or large-bore iv tubing or additional in-line filters. Volumes of the 250-ml saline bags for admixture decreased markedly with deviations in electrolyte composition after greater than 2 wk at 70 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Transfusão de Sangue/normas , Calefação/normas , Hemorragia/terapia , Transfusão de Sangue/instrumentação , Transfusão de Sangue/métodos , Emergências , Calefação/instrumentação , Calefação/métodos , Hemoglobinas/análise , Nefelometria e Turbidimetria , Fragilidade Osmótica , Potássio/análise , Controle de Qualidade , Cloreto de Sódio/uso terapêutico , Termografia , Preservação de Tecido/métodos , Preservação de Tecido/normasRESUMO
Red cell stability in the face of thermal stress has been evaluated only in the setting of prolonged incubation. This study was conducted to determine red cell tolerance of rapid mixture with heated saline, which exposes red cells to heat only until thermal equilibration, which is a matter of seconds. Half-units of 35-day-old red cells stored in CPDA-1 were mixed at 6 to 10 degrees C in the blood container with an equal weight of 60, 70, or 80 degrees C saline. This resulted in mean mixture temperatures of 30.9, 37.5, and 42.6 degrees C, respectively. Controls consisted of the same mixture, but with 6 to 10 degrees C saline. The red cells in the mixtures were assessed for osmotic fragility, and the supernatant was examined for plasma hemoglobin and potassium. Neither osmotic fragility curves nor supernatant hemoglobin or potassium changed significantly with saline temperatures of 60 or 70 degrees C. When 80 degrees C saline was used, osmotic fragility, supernatant hemoglobin, and potassium all increased significantly (p less than 0.01) over control values. Red cells tolerate rapid mixture with 70 degrees C saline without hemolysis or change in osmotic fragility.
Assuntos
Eritrócitos/fisiologia , Temperatura Alta , Cloreto de Sódio/farmacologia , Transfusão de Eritrócitos , Eritrócitos/efeitos dos fármacos , Hemoglobinas/análise , Hemólise , Humanos , Fragilidade Osmótica , Potássio/sangueRESUMO
Treatment for median knee-joint instability with a case history long time back may occasionally be time-consuming and dissatisfactory to patient and doctor. Several synthetic materials and autologous grafts are used in surgical therapy. Some of the methods are described in this paper. In one of them use of autologous tissue is combined with its "dynamisation".
Assuntos
Traumatismos do Joelho/cirurgia , Ligamentos Articulares/lesões , Doença Crônica , Humanos , Ligamentos Articulares/cirurgia , Ruptura , Técnicas de Sutura , CicatrizaçãoRESUMO
From 1980 to 1985 1,839 patients with thyroid nodules were investigated. 98% of them showed ultrasonic patterns of either echo-poor or complex structures, 85% of the nodules were scintigraphically cold, in 10% (n = 182) cytological findings were positive or at least suspect. Of these 182 patients 60 underwent operation, whereas 122 were followed up continuously. In 35 of 60 patients operated histological examination confirmed thyroid carcinomas. The combination of echo-poor, cold nodules and cytological positive or suspect findings urgently requires operation.