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1.
Eur J Neurol ; 22(10): 1329-36, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26130053

RESUMEN

BACKGROUND AND PURPOSE: In some patients with subarachnoid hemorrhage (SAH) a bleeding source cannot be identified. Perimesencephalic (PM) SAH is assumed to have an excellent outcome. Our objective was to analyze the long-term physical and psychological outcome of patients after non-aneurysmal SAH. METHODS: One hundred and seventy-three patients met the inclusion criteria. Short-term follow-up 6 months after SAH was assessed according to the modified Rankin Scale (0-2 favorable). A short-form health survey with 36 questions (SF-36) and eight scales was used as questionnaire for long-term follow-up. RESULTS: Thirty-seven answers were received from the two groups, PM and non-perimesencephalic (NPM) SAH, on average 76 months after ictus (range 1.5-14 years). PM- and NPM-SAH without Fisher grade 3 blood pattern have excellent short-term outcomes. The quality of life (QoL) is significantly reduced after non-aneurysmal SAH, especially in NPM-SAH. In particular, patients with a Fisher 3 blood pattern had significantly higher risks for cerebral vasospasm, delayed cerebral ischaemia, unfavorable outcome, reduced QoL and mortality in short- and long-term follow-up. CONCLUSIONS: Excluding rolph, only patients with a PM-SAH have a similar QoL at long-term follow-up compared to the standard population. Patients with NPM-SAH have a significantly decreased QoL in long-term follow-up. Furthermore, the Fisher 3 blood pattern group in particular had a significantly worse outcome - at short-term and long-term follow-up. Therefore the NPM-SAH group was stratified into patients with Fisher 3 blood pattern and patients without Fisher 3 in further investigations.


Asunto(s)
Evaluación de Resultado en la Atención de Salud , Calidad de Vida , Hemorragia Subaracnoidea/clasificación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
2.
Clin Neurol Neurosurg ; 137: 1-4, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26115049

RESUMEN

OBJECTIVE: Solitary spinal amyloidoma is a rare entity. Amyloidomas consist of extracellular amyloid deposits with an insoluble beta-pleated proteinaceous material. Although amyloidomas are slow growing lesions, they may lead to a progressive spinal cord or nerve root compression. Moreover amyloidoma results in destruction of bone with consequence of progressive osteolysis. METHOD: This study is a case presentation and review of the literature and should point out the need to explore any underlying diseases to guarantee the best therapy for the affected patient. In this case report we present a female patient with high-level paraparesis and lumbar stenosis in L2-L3 with combined spondylolisthesis (ASIA Impairemet Scale C). Paraparesis increased shortly after lumbar osteosynthesis. Contrast-enhanced MRI of the thoracic spine revealed medullary compression at the D5 level due to an epidural and paraspinal mass with concomitant bone infiltration. Operative decompression followed. Histopathological examination initially revealed amyloidoma. Finally the lesion was classified as a plasma cell myeloma. RESULTS: Plasma cell myeloma may rarely present as a solitary amyloidoma in the initial pathological examination with the potential to cause spinal cord compression associated to osteolytic lesions of the spine. CONCLUSION: A thorough pathological work-up is mandatory in order to rule out differential diagnosis and exclude possible underlying diseases.


Asunto(s)
Amiloidosis Familiar/patología , Vértebras Cervicales/patología , Espacio Epidural/patología , Mieloma Múltiple/patología , Enfermedades Cutáneas Genéticas/patología , Anciano , Amiloidosis Familiar/diagnóstico , Amiloidosis Familiar/cirugía , Vértebras Cervicales/cirugía , Descompresión Quirúrgica/métodos , Diagnóstico Diferencial , Femenino , Humanos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia , Enfermedades Cutáneas Genéticas/diagnóstico , Enfermedades Cutáneas Genéticas/cirugía
4.
Hamostaseologie ; 31(2): 111-7, 2011 May 02.
Artículo en Alemán | MEDLINE | ID: mdl-21152676

RESUMEN

UNLABELLED: Recently published studies give evidence, that an increased maximum lysis in the APTEM® - test (ML60 > 12%) of the ROTEM® (Tem International GmbH, Munich, Germany) might indicate a factor XIII deficiency (FXIII < 70%). It was the aim of this study to investigate the feasibility of thrombelastometric measurements with the ROTEM device to reflect the isolated influence of FXIII on clot stability and therefore to indicate potential factor XIII deficiencies. PATIENTS, METHOD: After approval by the local Scientific and Ethic Review Board, 26 consecutive patients, scheduled for elective craniotomy for tumour resection, were prospectively enrolled into this study. Blood samples were taken for conventional laboratory coagulation analyses, FXIII analyses and thrombelastometric measurements (EXTEM, FIBTEM and APTEM tests) after induction of general anaesthesia (T1), before skin incision (T2) as well as at (T3) and 24 hours after (T4) postoperative admission to ICU, respectively. Statistical analyses included Spearman rank order correlations and multiple linear regressions. RESULTS: FXIII concentrations did not correlate with the ML60 in the APTEM test at any measuring point. Neither platelet count nor fibrinogen nor FXIII concentrations were of predictive value for ML60 of the APTEM test. CONCLUSION: The results lead to the assumption that thrombelastometric measurements may not be appropriate for the perioperative monitoring of FXIII concentration.


Asunto(s)
Neoplasias Encefálicas/cirugía , Craneotomía , Deficiencia del Factor XIII/diagnóstico , Factor XIII/análisis , Tromboelastografía/instrumentación , Neoplasias Encefálicas/sangre , Deficiencia del Factor XIII/sangre , Estudios de Factibilidad , Humanos , Valor Predictivo de las Pruebas , Cuidados Preoperatorios , Estudios Prospectivos
5.
Respir Med ; 103(1): 22-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19022642

RESUMEN

BACKGROUND: Tiotropium, a once daily inhaled anticholinergic delivered via HandiHaler, provides bronchodilation for >24h and improves patient-centred outcomes. The Respimat Soft Mist Inhaler (SMI), a novel, propellant-free inhaler, has been developed and proposed as an alternative delivery device for use with tiotropium. METHODS: In a pre-specified, pooled analysis of two 30-week, double-blind, double-dummy, crossover studies, 207 patients with Chronic Obstructive Pulmonary Disease (COPD) were randomised to receive once daily tiotropium 5 microg or 10 microg (aqueous solution delivered via Respimat SMI), tiotropium 18 microg (inhalation powder via HandiHaler) or placebo. The primary endpoint was trough forced expiratory volume in 1s (FEV(1)) response. Forced vital capacity (FVC), peak expiratory flow rate (PEFR), rescue medication use, safety and pharmacokinetics (in a subgroup of patients) were also assessed. RESULTS: Both tiotropium doses delivered by Respimat SMI were significantly superior to placebo and non-inferior to tiotropium 18 microg HandiHaler on the primary endpoint (all p<0.0001). All active treatments were significantly superior to placebo (all p<0.0001) and both doses of tiotropium Respimat SMI were non-inferior to tiotropium 18 microg HandiHaler on the secondary spirometry variables and rescue medication use. The systemic exposure was similar between tiotropium 5 microg Respimat SMI and tiotropium 18 microg HandiHaler but was higher for tiotropium 10 microg Respimat SMI. All active treatments were well tolerated. CONCLUSIONS: Tiotropium 5 microg Respimat SMI is comparable with tiotropium 18 microg HandiHaler in terms of efficacy, pharmacokinetics and safety. Respimat SMI is an effective alternative, multi-dose delivery device for tiotropium.


Asunto(s)
Broncodilatadores/administración & dosificación , Inhaladores de Dosis Medida , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Derivados de Escopolamina/administración & dosificación , Administración por Inhalación , Anciano , Broncodilatadores/farmacocinética , Broncodilatadores/uso terapéutico , Estudios Cruzados , Método Doble Ciego , Esquema de Medicación , Femenino , Volumen Espiratorio Forzado/efectos de los fármacos , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Derivados de Escopolamina/farmacocinética , Derivados de Escopolamina/uso terapéutico , Bromuro de Tiotropio , Resultado del Tratamiento
6.
Zentralbl Neurochir ; 68(2): 87-90, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17614090

RESUMEN

OBJECTIVE: In spontaneous intracranial hypotension (SIH), also known as spontaneous hypoliquorrhea, an abnormally low intracranial pressure leads to posture-dependent headaches similar to those observed after lumbar puncture. Although its etiology is not yet fully understood, it is now diagnosed more often as clinical awareness increases and the availability of MRI becomes more widespread. CLINICAL PRESENTATION: We report the case of a 42-year-old patient with SIH who developed bilateral subdural hematomas (SDH) and symptomatic diencephalic herniation requiring surgical evacuation. Remarkably, he also developed partial pituitary insufficiency. THERAPY: After SDH was evacuated twice without success, his symptoms resolved rapidly after a diagnostic myelography. CONCLUSION: Besides the orthostatic headache, the possible clinical manifestations are numerous. Serious complications and situations may occur that need to be recognized and treated. In addition to presentation of the case the literature to date is reviewed and discussed.


Asunto(s)
Antiinflamatorios/uso terapéutico , Hematoma Subdural/etiología , Hematoma Subdural/terapia , Hipotensión Intracraneal/complicaciones , Hipotensión Intracraneal/terapia , Mielografía , Esteroides/uso terapéutico , Adulto , Electroencefalografía , Encefalocele/fisiopatología , Cefalea/etiología , Hematoma Subdural/diagnóstico , Humanos , Hipotensión Ortostática/fisiopatología , Hipotensión Intracraneal/diagnóstico , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada por Rayos X
7.
Arch Virol ; 151(2): 255-71, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16195789

RESUMEN

The development of effective gene-therapeutic applications for cardiovascular disorders is in part limited by the lack of appropriate delivery systems. In an attempt to overcome this deficiency, we investigated the ability of baculoviral vectors to transduce human cardiovascular cells, for which data are missing in literature. Additionally, baculovirus ability to transduce target cells was compared to that of an adenoviral vector, a well characterized and widely used viral vector. Transduction experiments, performed using baculo/adenoviral vectors expressing the enhanced green fluorescence protein, revealed that, under the experimental condition considered, baculoviruses but not adenoviruses efficiently transduce human coronary smooth muscle cells (hCSMC); an opposite behavior was noticed for human coronary endothelial cells (hCEC). Thus, baculoviral vectors are potentially indicated as transfer system in the treatment of coronary restenosis, where growth inhibitory genes should reach hCSMC but not hCEC. When used to transduce human cardiomyocytes and fibroblasts, both vectors behaved similarly. Finally, studies on cellular DNA replication revealed a more prolonged and pronounced negative effect on cells transduced by adenoviral compared to baculoviral vectors. Our data indicate that baculoviruses represent an attractive alternative to adenoviruses as transfer vectors in cardiovascular cells and that baculovirus have the potential to be used as gene transfer system in cardiovascular diseases such as restenosis.


Asunto(s)
Adenoviridae/genética , Baculoviridae/genética , Sistema Cardiovascular/citología , ADN Recombinante/genética , Vectores Genéticos/genética , Transducción Genética/métodos , Animales , Línea Celular , Vasos Coronarios/citología , Células Endoteliales/metabolismo , Fibroblastos , Regulación de la Expresión Génica , Humanos , Insectos , Músculo Liso Vascular/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos del Músculo Liso/metabolismo , Porcinos
8.
J Environ Monit ; 3(5): 543-7, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11695126

RESUMEN

The first screening of polybrominated diphenyl ethers (PBDEs) in sediments and blue mussels (Mytilus edulis) collected in the Danish marine and freshwater environment is presented in this work. 10 marine and 6 freshwater sediments, together with blue mussels from 15 locations were analysed for PBDEs. The sum of 5 PBDE congeners (BDE47, BDE99, BDE100, BDE153, and BDE209) is in the range of 0.06-24.7 and 0.07-10.6 ng g-1 dry weight in marine and freshwater sediments, respectively. In blue mussels the sum of the 4 lower brominated congeners (BDE47, BDE99, BDE100, and BDE153) is in the range of 0.08-0.81 ng g-1 wet weight. The highest contamination with PBDEs are found in sediment and blue mussels close to populated areas. Generally, freshwater sediments contained higher levels of PBDEs compared to marine sediments, except for the high levels found in Copenhagen harbour. Ranking of the concentration of PBDEs in sediment from Denmark gives the following order: BDE209 >> BDE99 > BDE47 > BDE100 > BDE153. The congener pattern in the industrial product Bromkal 70-5DE is compared with the pattern found in sediment, blue mussels and fish from the Danish environment. The comparisons show that BDE47 is both bioconcentrated and biomagnified to a higher degree than any of the other congeners, whereas the amount of BDE99 decreases at higher trophic levels.


Asunto(s)
Bivalvos , Éteres/farmacocinética , Sedimentos Geológicos/química , Bifenilos Polibrominados/farmacocinética , Animales , Disponibilidad Biológica , Monitoreo del Ambiente , Éteres/análisis , Cadena Alimentaria , Bifenilos Polibrominados/análisis , Distribución Tisular
9.
Antisense Nucleic Acid Drug Dev ; 11(5): 271-87, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11763345

RESUMEN

Proliferation of vascular smooth muscle cells is generally accepted as a key event in the development of restenosis following percutaneous transluminal angioplasty. To prevent human restenosis, we have designed a molecular strategy based on hammerhead ribozymes targeted against the mRNA of cyclin E and E2F1, two proteins relevant in cell cycle progression whose regulation is interconnected by a positive feedback loop. Following the identification of accessible ribozyme target sites by RNase H mapping, several hammerhead ribozymes were generated that cleave with comparable efficiency two different splice forms of cyclin E mRNA and the full-length and a truncated form of E2F1 RNA, respectively. The most active ribozymes were tested in vitro under single-turnover conditions yielding k(react)/K(m) ratios between 36 and 73 x 10(4) M(-1) min(-1), which places them in the top range ribozymes targeted against long and structured substrates. In addition, we show that the most active ribozyme selected in vitro reduces specifically and significantly (p < 0.0028) proliferation of cultured human vascular smooth muscle cells (VSMC).


Asunto(s)
Proteínas de Ciclo Celular , Ciclina E/genética , Proteínas de Unión al ADN , ARN Catalítico/farmacología , ARN Mensajero/genética , Factores de Transcripción/genética , Secuencia de Bases , División Celular/efectos de los fármacos , Células Cultivadas , Cartilla de ADN , Factores de Transcripción E2F , Factor de Transcripción E2F1 , Humanos , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos
10.
Gen Comp Endocrinol ; 119(1): 85-94, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10882553

RESUMEN

The African bullfrog Pyxicephalus adspersus is generally classified along with frogs of the genus Rana in the subfamily Raninae of the family Ranidae but precise phylogenetic relationships between species are unclear. Pancreatic polypeptide (PP), insulin, and glucagon-like peptide (GLP-1) were isolated from an extract of P. adspersus pancreas and characterized structurally. A comparison of the amino acid sequence of Pyxicephalus PP (APSEPQHPGG(10)QATPEQLAQY(20)YSDLYQYITF(30)ITRPRF++ +. NH(2)) with those of the known amphibian PP molecules in a maximum parsimony analysis generates a single phylogenetic tree in which Pyxicephalus is the sister to the clade comprising the members of the genus Rana. The three orders of living amphibians form discrete clades with the representative of the Gymnophiona appearing as sister to the Caudata-Anura. In contrast, Pyxicephalus insulin (A chain, GIVEQCCHSA(10)CSLYDLENYC(20)N; B-chain, LANQHLCGSH(10)LVEALYMVCG(20)ERGFFYYPKS(30)) and and GLP-1 (HAEGTFTSDM(10)TSYLEEKAAK(20)EFVDWLIKGR(30)PK) resemble more closely the corresponding peptides from the cane toad Bufo marinus than the peptides from any species of Rana. Cladistic analysis based upon the amino acid sequences of insulin produced a polyphyletic assemblage with the Gymnophiona nesting within an unresolved clade containing the non-ranid frogs. The data support the assertion that the amino acid sequence of PP, but not those of the other islet hormones, is of value as a molecular marker for inferring phylogenetic relationships between early tetrapod species.


Asunto(s)
Hormonas Pancreáticas/química , Filogenia , Ranidae/clasificación , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Glucagón/química , Glucagón/aislamiento & purificación , Péptido 1 Similar al Glucagón , Insulina/química , Insulina/aislamiento & purificación , Datos de Secuencia Molecular , Polipéptido Pancreático/química , Polipéptido Pancreático/aislamiento & purificación , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Precursores de Proteínas/química , Precursores de Proteínas/aislamiento & purificación , Homología de Secuencia , Especificidad de la Especie
11.
Eur J Biochem ; 267(3): 894-900, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10651828

RESUMEN

The skins of frogs of the genus Rana synthesize a complex array of antimicrobial peptides that may be grouped into eight families on the basis of structural similarity. A total of 24 peptides with differential growth-inhibitory activity towards the Gram-positive bacterium Staphylococcus aureus, the Gram-negative bacterium Escherichia coli and the yeast Candida albicans were isolated from extracts of the skins of three closely related North American frogs, Rana luteiventris (spotted frog), Rana berlandieri (Rio Grande leopard frog) and Rana pipiens (Northern leopard frog). Structural characterization of the antimicrobial peptides demonstrated that they belonged to four of the known families: the brevinin-1 family, first identified in skin of the Asian frog Rana porosa brevipoda; the esculentin-2 family, first identified in the European frog Rana esculenta; the ranatuerin-2 family, first identified in the North American bullfrog Rana catesbeiana; and the temporin family, first identified in the European frog Rana temporaria. Peptides belonging to the brevinin-2, ranalexin, esculentin-1 and ranatuerin-1 families were not identified in the extracts. Despite the close phylogenetic relationship between the various species of Ranid frogs, the distribution and amino-acid sequences of the antimicrobial peptides produced by each species are highly variable and species-specific, suggesting that they may be valuable in taxonomic classification and molecular phylogenetic analysis.


Asunto(s)
Proteínas Anfibias , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos , Péptidos/aislamiento & purificación , Péptidos/farmacología , Ranidae/metabolismo , Piel/química , Secuencia de Aminoácidos , Animales , Antibacterianos , Antiinfecciosos/química , Candida albicans/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Femenino , Masculino , Datos de Secuencia Molecular , Péptidos/química , Rana pipiens/metabolismo , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Staphylococcus aureus/efectos de los fármacos
12.
J Pept Res ; 54(6): 522-7, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10604597

RESUMEN

Three peptides with growth-inhibitory activity towards the gram-negative bacterium Eschericia coli were isolated from electrically stimulated secretions from the skin of the southern leopard frog, Rana sphenocephala. Structural characterization demonstrated that the peptides [brevinin-1Sa, minimum inhibitory concentration (MIC) = 55 microM; brevinin-1Sb, MIC = 17 microM; brevinin-1Sc, MIC = 14 microM] represent new members of the brevinin-1 family of antimicrobial peptides, previously isolated from several other species of frogs of the genus Rana. Their high concentration in skin secretions and extreme variability in amino acid sequence suggest that the brevinin family of peptides may be of value as molecular markers for the identification and taxonomic classification of Ranid frogs.


Asunto(s)
Proteínas Anfibias , Antibacterianos/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos , Péptidos/aislamiento & purificación , Piel/metabolismo , Secuencia de Aminoácidos , Animales , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Péptidos/metabolismo , Péptidos/farmacología , Ranidae , Homología de Secuencia de Aminoácido
13.
Artif Organs ; 23(1): 15-22, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9950174

RESUMEN

Dialysis membranes made from regenerated cellulose are under dispute because of their alleged lack of hemocompatibility. The introduction of membranes from synthetically modified cellulose, like cellulose acetate or Hemophan, has proven, however, that hemocompatible membranes can be fabricated from cellulose by means of chemical surface modifications. In addition to membranes made from modified cellulose like ethers or esters, which were investigated in earlier experiments, we looked for further cellulose modifications to be assessed for their hemocompatibility. For this purpose, we synthesized a series of cellulose carbamate derivatives to profit from the excellent hemocompatibility pattern of the urethane family. In vitro investigations on membranes made from these cellulose modifications proved a direct relationship between the degree of modification and hemocompatibility. This was proven for the following 3 representative hemocompatibility parameters: complement C5a generation, thrombin-antithrombin (TAT) III formation, and platelet count (PC). As already shown for modifications made from cellulose esters, a direct dependency between improved hemocompatibility and the degree of substitution (DS) in the cellulose molecule could be found. In our experiments, a degree of substitution below a value of 0.1 led to a nearly complete suppression of complement activation for all cellulose carbamates under investigation. In contrast to data on cellulose esters, we observed that molecular weight or molecular conformation of chemical substituents exerted only a minor effect on the hemocompatibility pattern. In addition, data on cellulose carbamate esters (e.g., cellulose succinate-phenyl-carbamate) show that a simultaneous but balanced substitution with hydrophilic and hydrophobic groups at the surface of the cellulose polymer is a further prerequisite for optimal hemocompatibility. It seems that the carbamate configuration per se has a positive effect on the hemocompatibility pattern of synthetically modified cellulose membranes.


Asunto(s)
Materiales Biocompatibles , Carbamatos , Celulosa , Membranas Artificiales , Diálisis Renal/instrumentación , Antitrombina III/biosíntesis , Materiales Biocompatibles/química , Sangre , Carbamatos/química , Celulosa/análogos & derivados , Celulosa/química , Activación de Complemento , Complemento C5a/biosíntesis , Humanos , Conformación Molecular , Peso Molecular , Péptido Hidrolasas/biosíntesis , Recuento de Plaquetas , Propiedades de Superficie , Uretano/química , Agua/química
14.
Gen Comp Endocrinol ; 112(2): 146-52, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9784297

RESUMEN

It has been suggested that the amino acid sequence of pancreatic polypeptide (PP) may provide a useful molecular marker with which to study evolutionary relationships between tetrapods but few PP sequences from amphibia are available to test this hypothesis. PPs have been purified from the pancreata of five species belonging to the different orders of amphibians. Their amino acid sequences were established as: APSEPEHPGD10 NASPDELAKY20 YSDLWQYITF30 VGRPRY for the lesser siren, Siren intermedia (Caudata); GPTEPIHPGK10 DATPEELTKY20 YSDLYDYITL30 VGRSRW for the caecilian, Typhlonectes natans (Gymnophiona); and TPSEPQHPGD10 QASPEQLAQY20 YSDLWQYITF30 VTRPRF for the cane toad, Bufo marinus (Anura). The structure of Rana sylvatica PP is the same as that of Rana catesbeiana PP whereas PP from the green frog Rana ridibunda contains one substitution (His6 --> Gln). The data provide further support for the conclusion that the amino acid sequence of PP has been poorly conserved during evolution with only 17 residues invariant among the eight species of amphibia yet studied and only 8 residues (Pro5, Pro8, Gly9, Ala12, Leu24, Tyr27, Arg33, and Arg35) invariant among all tetrapods. A maximum parsimony analysis based upon the amino acid sequence of PP and using the sequence of frog PYY as outgroup to polarize the in-group taxa generates a consensus phylogenetic tree in which the Amniota and Amphibia form two distinct clades. However, such a tree does not permit valid conclusions to be drawn regarding branching order within the Amphibia.


Asunto(s)
Anfibios/genética , Variación Genética , Polipéptido Pancreático/química , Secuencia de Aminoácidos , Animales , Biomarcadores , Cromatografía Líquida de Alta Presión , Secuencia de Consenso , Evolución Molecular , Humanos , Datos de Secuencia Molecular , Polipéptido Pancreático/genética , Polipéptido Pancreático/aislamiento & purificación , Radioinmunoensayo
15.
Gen Comp Endocrinol ; 107(3): 421-7, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9268623

RESUMEN

Among the extant Sarcopterygii, the interrelationship between the Dipnoi (lungfishes), Actinistia (coelacanths), and Tetrapoda (tetrapods) is controversial. Insulin has been purified from an extract of the pancreas of the African lungfish Protopterus annectens and its primary structure established as A-chain, Gly-Ile-Val-Glu-Gln-Cys-Cys-His-Lys-Pro10-Cys-Ser-Leu- Tyr -Glu-Leu-Glu-Asn-Tyr-Cys20-Asn-Val-Pro; and B-chain, Ala-Val-Leu-Asn-Gln-His-Leu-Cys-Gly-Ser10-His-Leu-Val- Glu- Ala-Leu-Tyr-Leu-Val-Cys20-Ala-Asp-Asn-Gly-Phe- Phe-Tyr-Lys-Pro-Ser30-Gly. Lungfish insulin contains unusual structural features, such as the dipeptide extension to the C-terminus of the A-chain and the substitution Arg --> Asn at position B-23 in the putative receptor binding region of insulin, which may be expected to influence appreciably its biological potency relative to mammalian insulins. Lungfish insulin also contains amino acid substitutions such as Gly --> Ala at position B-21, Glu --> Asp at position B-22, and a Lys --> Ser residue at position B-30, previously found in insulins from amphibia. This observation is consistent with paleontological data suggesting that lungfish and amphibia share a close phylogenetic relationship.


Asunto(s)
Peces/fisiología , Insulina/química , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Femenino , Insulina/aislamiento & purificación , Masculino , Datos de Secuencia Molecular , Páncreas/química , Radioinmunoensayo , Especificidad de la Especie
16.
Plant Mol Biol ; 15(1): 39-47, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2103441

RESUMEN

We have shown leaf-specific inhibition GUS gene expression in transgenic Nicotiana plants using an antisense RNA with a 41-base homology spanning the translation start codon of the gene. GUS was expressed from the nominally constitutive 35S promoter and the antisense RNA was expressed from the light-regulated ca/b promoter of Arabidopsis thaliana. A range of GUS inhibition from 0 to 100% was obtained by screening a small population of transgenic plants and the specific levels of inhibition observed were stably inherited in two generations. An antiGUS 'gene' dosage effect was observed in plants which were homozygous for antiGUS. RNA detection results suggest that duplex formation with the 41 base pair antiGUS RNA destabilized the GUS mRNA and that an excess of antisense RNA was not required. Our results demonstrate the potential of antisense RNA as a strategy for obtaining plant mutants, especially 'down mutations' in essential genes where only a short 5' sequence of the mRNA is required. They also suggest that the 'position effect' on gene expression could be used in conjunction with an antisense RNA strategy to provide a versatile approach for crop improvement.


Asunto(s)
Plantas/genética , ARN sin Sentido/genética , Secuencia de Bases , ADN/genética , Regulación Enzimológica de la Expresión Génica , Glucuronidasa/genética , Datos de Secuencia Molecular , Plantas/metabolismo , Plantas Tóxicas , Plásmidos , Regiones Promotoras Genéticas , ARN sin Sentido/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Nicotiana/genética , Nicotiana/metabolismo
17.
Science ; 179(4080): 1334-6, 1973 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-4539982

RESUMEN

Electrophoretic comparison of hemoglobin samples from numerous populations of Rana pipiens in Arizona reveals three distinct phenotypes that closely correlate with morphological differences. Hemoglobin samples from sympatric locations contain parental phenotypes with only the occasional occurrence of a hybrid. These data support the contention that the Rana pipiens complex consists of several species.


Asunto(s)
Hemoglobinas , Animales , Anuros , Arizona , Electroforesis de las Proteínas Sanguíneas , Fenotipo , Rana pipiens
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