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1.
Mol Phylogenet Evol ; 195: 108046, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38447924

RESUMEN

The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on âˆ¼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.


Asunto(s)
Unio , Animales , Filogenia , Filogeografía , Unio/genética , Europa (Continente) , ADN Mitocondrial/genética , Variación Genética
2.
Euro Surveill ; 19(39)2014 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-25306981

RESUMEN

On 15 August 2012, an increase in the number of Salmonella Thompson cases was noticed by the Salmonella surveillance in the Netherlands. A case­control study was performed, followed by a food investigation. In total 1,149 cases were laboratory-confirmed between August and December 2012 of which four elderly (76­91 years) were reported to have died due to the infection. The cause of the outbreak was smoked salmon processed at a single site. The smoked salmon had been continuously contaminated in the processing lines through reusable dishes, which turned out to be porous and had become loaded with bacteria. This is the largest outbreak of salmonellosis ever recorded in the Netherlands. The temporary closure of the processing site and recall of the smoked salmon stopped the outbreak. An estimated four to six million Dutch residents were possibly exposed to the contaminated smoked salmon and an estimated 23,000 persons would have had acute gastroenteritis with S. Thompson during this outbreak. This outbreak showed that close collaboration between diagnostic laboratories, regional public health services, the national institute for public health and the food safety authorities is essential in outbreak investigations.


Asunto(s)
Brotes de Enfermedades , Productos Pesqueros/microbiología , Salmón/microbiología , Intoxicación Alimentaria por Salmonella/mortalidad , Infecciones por Salmonella/mortalidad , Salmonella enterica/aislamiento & purificación , Anciano , Anciano de 80 o más Años , Animales , Estudios de Casos y Controles , Diarrea/epidemiología , Productos Pesqueros/análisis , Manipulación de Alimentos/métodos , Gastroenteritis/epidemiología , Humanos , Masculino , Países Bajos/epidemiología , Vigilancia de la Población , Intoxicación Alimentaria por Salmonella/diagnóstico , Intoxicación Alimentaria por Salmonella/microbiología , Infecciones por Salmonella/diagnóstico , Infecciones por Salmonella/microbiología , Salmonella enterica/clasificación , Encuestas y Cuestionarios
7.
Haemophilia ; 17(6): 872-4, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21342368

RESUMEN

Haemorrhagic manifestations in patients with haemophilia A and B are considered quite similar for comparable level of factor deficiency. We investigated the bleeding frequency and factor usage between HA and HB patients with comparable disease severities. We collected data on frequency of bleeds and factor concentrate utilization over 3 years, from January 2001 to December 2003. Information was gathered from home infusion logs recorded by patients or their parents, and treatment records from the Hemophilia Clinic or the Hospital Emergency Department. Data were available on 58 patients with severe HA (FVIII < 0.01 U mL(-1)), 10 with moderate HA (FVIII < 0.05 U mL(-1)), 15 with severe HB, and five with moderate HB who required treatment for episodic bleeds, postoperative haemostasis and for primary or secondary prophylaxis. The HA patients bled more frequently than HB patients (14.4 vs. 8.63 bleeds/patient/year), but used similar amounts of concentrate per year. HA patients underwent surgical procedures 3.2 times more frequently than HB patients to correct musculoskeletal complications. A total of 21,363,409 IU of recombinant FVIII was used by patients with HA (104,722 IU/patient/year) and 6,430, 960 IU of recombinant factor IX, by patients with HB (107,182 IU/patient/year). The difference in factor concentrate usage is not statistically significant (P > 0.05). The decrease in bleed frequency in haemophilia B indicates that the conclusions from randomized trials of prophylaxis in HA may not be accurately applied to HB.


Asunto(s)
Coagulantes/administración & dosificación , Factor IX/administración & dosificación , Factor VIII/administración & dosificación , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Hemofilia B/complicaciones , Hemofilia B/tratamiento farmacológico , Hemorragia/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Humanos , Lactante , Persona de Mediana Edad , Proteínas Recombinantes/administración & dosificación , Estudios Retrospectivos , Adulto Joven
8.
Klin Padiatr ; 222(3): 134-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20514615

RESUMEN

BACKGROUND: Neonatal aortic thrombosis is a rare occurrence, but can be fatal. Treatment of this condition is hampered by the lack of large studies involving this pediatric population. Reporting of this condition is also not standardized. METHODS: The purpose of this review is to collate available literature on the incidence, risk factors, presentation, treatment and outcome of neonatal aortic thrombosis as well as suggest a treatment model. RESULTS: A Medline search of PubMed, OVID and Cochrane databases was undertaken using the key words "neonatal", "infant", "aorta", "aortic", "thrombosis", "thrombus" and "clot". Limits were set for articles that were English language only and published between 1980 and September 2009. Following review of all articles using predetermined search words and criteria, 38 were found with sufficient data for our purpose. The reported total number of neonatal patients with aortic thrombosis was 148 and 78% of the aortic thromboses in this review were related to arterial umbilical catheterization. CONCLUSIONS: We have suggested a classification system to standardize reporting of neonatal aortic thrombosis, as well as a treatment decision tree, and a clinical guide for the treatment of thrombosis in children. As always, clinicians should balance the risks and benefits of their decision to treat with the level of local expertise. This guide may specifically serve the neonatal population with line-related aortic thrombosis.


Asunto(s)
Enfermedades de la Aorta/etiología , Enfermedades del Prematuro/etiología , Trombosis/etiología , Anticoagulantes/uso terapéutico , Enfermedades de la Aorta/diagnóstico , Enfermedades de la Aorta/epidemiología , Enfermedades de la Aorta/terapia , Aortografía , Catéteres de Permanencia/efectos adversos , Estudios Transversales , Humanos , Recién Nacido , Enfermedades del Prematuro/diagnóstico , Enfermedades del Prematuro/epidemiología , Enfermedades del Prematuro/terapia , Sistema de Registros , Factores de Riesgo , Terapia Trombolítica , Trombosis/diagnóstico , Trombosis/epidemiología , Trombosis/terapia , Resultado del Tratamiento , Ultrasonografía , Arterias Umbilicales
10.
RSC Adv ; 8(26): 14713-14721, 2018 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-35540740

RESUMEN

Polyamide 6/modified silica composite materials have been prepared by a coupled polymerization procedure. For this purpose, the three-component-system we presented in a previous publication, consisting of ε-aminocaproic acid (ε-ACA), ε-caprolactam (ε-CL), and 1,1',1'',1'''-silanetetrayltetrakis-(azepan-2-one) (Si(ε-CL)4), has been combined with other silicon monomers with one or two methyl groups (MeSi(ε-CL)3 and Me2Si(ε-CL)2). The simultaneous polymerization of ε-CL and silicon monomers leads to the in situ formation of silica/polysiloxane particles and the surrounding polyamide 6 matrix in one step. Moreover, 3-aminopropyltriethoxysilane has been added to the three-component-system to achieve covalent bonding between organic and inorganic phases and to inhibit agglomeration of the silica particles. Chemical structures and morphologies of the composites have been investigated by solid-state NMR and FTIR spectroscopy as well as electron microscopy and SEC measurements. Structural effects on thermal properties have been studied by DSC and TGA measurements.

11.
RSC Adv ; 8(55): 31673-31681, 2018 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35548201

RESUMEN

Organic-inorganic hybrid materials with urethane functionalities were obtained by simultaneous twin polymerization of twin prepolymers in combination with the ideal twin monomer 2,2'-spirobi[4H-1,3,2-benzodioxasiline]. The twin prepolymers consist of a urethane-based prepolymer with reactive terminal groups which can react during the twin polymerization process. Nanostructured hybrid materials with integrated dialkylsiloxane crosslinked urethane structures, phenolic resin and SiO2 are obtained in a one pot process. The effects of the polymerization temperature as well as those of various catalysts and reagent ratios on the polymerization behavior were investigated. The molecular structures of the obtained materials were determined by 13C- and 29Si-{1H}-CP-MAS NMR spectroscopies. HAADF-STEM-measurements were performed to prove the distribution of silicon in the hybrid material.

13.
Biochim Biophys Acta ; 1129(2): 145-8, 1992 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-1730051

RESUMEN

An inhibitor of elongation factor G (EF-G) GTPase isolated from the ribosome wash of Escherichia coli was shown to stimulate the poly(A,U,G)- and initiation factor 2 (IF2)-dependent binding of N-formyl-[35S]Met-tRNAfMet to ribosomes. In the presence of saturating amounts of the EF-G GTPase inhibitor, neither addition of initiation factor 1 (IF1) nor addition of initiation factor 3 (IF3) caused a further stimulation of the formation of N-formyl-[35S]Met-tRNAfMET/poly(A,U,G)/ribosome complexes. Both IF1 and IF3 were shown to inhibit ribosome-dependent EF-G GTPase, especially when both initiation factors were added either in absence or in the presence of initiation factor 2 (IF2), poly(A,U,G) and N-formyl-Met-tRNAfMet. Therefore, we conclude that the EF-G GTPase inhibitor consisting of two polypeptide subunits with apparent molecular masses of 23,000 and 10,000 Da is a complex of initiation factors IF1 and IF3. The inhibition of EF-G GTPAse by IF3, but not the effects of IF1 in the presence or absence of IF3 could be reversed by increasing the Mg(2+)-concentration as already shown for the EF-G GTPase inhibitor. Therefore, IF1 as well as the EF-G GTPase inhibitor do not influence the ribosome-dependent EF-G GTPase by affecting the association of ribosomal subunits.


Asunto(s)
Proteínas Bacterianas/análisis , Escherichia coli/química , Factor 1 Eucariótico de Iniciación/análisis , Factores de Elongación Enlazados a GTP Fosfohidrolasas/antagonistas & inhibidores , Factores de Elongación de Péptidos/antagonistas & inhibidores , Factores de Iniciación de Péptidos/análisis , Ribosomas/química , Factor 1 Eucariótico de Iniciación/fisiología , Factor 2 Eucariótico de Iniciación/fisiología , Factor G de Elongación Peptídica , Factores de Elongación de Péptidos/fisiología , Factores de Iniciación de Péptidos/fisiología , Polirribonucleótidos/metabolismo , Factor 1 Procariótico de Iniciación , Factor 3 Procariótico de Iniciación , ARN de Transferencia de Metionina/metabolismo , Ribosomas/metabolismo
14.
Biochim Biophys Acta ; 1174(2): 153-61, 1993 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-8357832

RESUMEN

The elongation factor G (EF-G) GTPase activity is induced by either 70S ribosomes or 50S ribosomal subunits. The GTPase activity induced by 50S ribosomal subunits is predominant at low concentrations of monovalent cations and decreases with increasing concentrations of K+ or NH4+. Double-logarithmic plots of the data reveal straight lines with different slopes for low and high concentrations of monovalent cations, respectively, intersecting at the same concentration of monovalent cations where maximal EF-G GTPase activity is measured in the presence of both ribosomal subunits. Substantially the same curves are obtained when 50S ribosomal subunits are substituted by 50S CsCl-core particles partially reconstituted by addition of purified 50S split proteins L7/L12. Intact 30S ribosomal subunits, but not 30S CsCl-core particles are able to associate with 50S ribosomal subunits and to modulate ribosome-dependent EF-G GTPase activity. Therefore, our data clearly show that the biphasic courses of the NH4+ and K+ curves of EF-G GTPase activity induced by 50S ribosomal subunits are not due to contaminations with 30S ribosomal subunits but result from different conformations of EF-G/50S ribosomal-subunit complexes at low and high concentrations of monovalent cations, respectively. CD spectra of 50S ribosomal subunits measured under different salt conditions have shown that the conformation of the 50S ribosomal subunits is strongly dependent on the concentration of monovalent cations. The conformation of 30S ribosomal subunits is, however, considerably stronger influenced by the Mg2+ than by the concentration of monovalent cations. The salt effects on the conformation of the 30S ribosomal subunits correspond to the salt effects on the association of ribosomal subunits and the modulation of EF-G GTPase activity by 30S ribosomal subunits. Since, in the presence of both ribosomal subunits, EF-G GTPase activity is maximal at the same concentration of monovalent cations where obviously a spontaneous conformation change of 50S ribosomal subunits takes place, we postulate that EF-G GTPase primarily acts on the ribosomes by changing the conformation of 50S ribosomal subunits. The resulting model is based on the assumption that EF-G GTPase activity is considerably more strongly induced by the 'substrate conformation' ('state I') than by the 'product conformation' of the 50S ribosomal subunits ('state II'). A spontaneous transformation of 'state II' to 'state I' is expected to occur in the absence of mRNA, aminoacyl-tRNA and EF-T especially under salt conditions favouring state I.


Asunto(s)
Factores de Elongación Enlazados a GTP Fosfohidrolasas/metabolismo , Factores de Elongación de Péptidos/metabolismo , ARN Ribosómico/química , Ribosomas/metabolismo , Cationes , Dicroismo Circular , Escherichia coli/metabolismo , Guanosina Trifosfato/metabolismo , Conformación de Ácido Nucleico , Factor G de Elongación Peptídica
15.
Pharmacotherapy ; 13(3): 177-88, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8321732

RESUMEN

Oligonucleotide pharmacotherapy, although in a very preliminary stage, promises to provide new, highly specific tools for the treatment of human diseases, such as viral illnesses and cancer. The agents have several proposed mechanisms of action, including inhibition of translation, splicing, and transcription. In addition, the bioefficacy of oligonucleotides may be enhanced by phosphorothioates, methylphosphonates, and alpha-oligonucleotides. The agents are delivered by the ex vivo or topical route, and new methods of administration are under study. It is predicted that within the decade these agents will be used routinely to treat several serious illnesses.


Asunto(s)
Oligonucleótidos , Sistemas de Liberación de Medicamentos , Diseño de Fármacos , Humanos , Neoplasias/tratamiento farmacológico , Oligonucleótidos/química , Oligonucleótidos/genética , Oligonucleótidos/uso terapéutico , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Antisentido/uso terapéutico , Biosíntesis de Proteínas/genética , Empalme del ARN/genética , Transcripción Genética/genética , Virosis/tratamiento farmacológico
16.
Rofo ; 151(3): 289-93, 1989 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-2477878

RESUMEN

During nine years, percutaneous transhepatic biliary drainage was carried out 616 times on 563 patients in the Department of Radiology, University of Mainz Medical School. 50.3% were pre-operative and 39% were palliative. More than 80% were necessitated by malignant lesions. Subsequent improvements in biochemical measurements were observed in 82.4% of patients. Complications of the procedure led to the death of five patients (0.8%) and required surgery in nine patients (1.5%). The following complications were observed: biliary peritonitis in 0.6%, sepsis in 1.9%, bleeding in 1.9% and fever higher than 38 degrees C in 16.2%.


Asunto(s)
Sistema Biliar , Drenaje/métodos , Sistema Biliar/diagnóstico por imagen , Colestasis/diagnóstico por imagen , Colestasis/etiología , Colestasis/terapia , Drenaje/efectos adversos , Femenino , Humanos , Yopamidol , Hígado/diagnóstico por imagen , Masculino , Cuidados Paliativos , Cuidados Preoperatorios , Punciones/efectos adversos , Punciones/métodos , Radiografía Intervencional
17.
Rofo ; 147(6): 623-8, 1987 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-2827254

RESUMEN

Contrast administration through the superior mesenteric or splenic arteries provided additional information in 22 out of 31 patients, when compared with intravenous contrast bolus for CT of the liver. In 11 patients, the demonstration of a tumour lead to a change in treatment. False positive findings occurred in four of the 31 patients. In 2 patients intrahepatic lesions were overlooked, but were found during angiography carried out at the same examination. The diagnosis of intrahepatic space-occupying lesions is discussed as well as the CT appearances of portal-venous liver perfusion.


Asunto(s)
Yopamidol/administración & dosificación , Hígado , Vena Porta , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Estudios de Evaluación como Asunto , Reacciones Falso Negativas , Femenino , Humanos , Hígado/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Masculino , Arterias Mesentéricas/diagnóstico por imagen , Persona de Mediana Edad , Vena Porta/diagnóstico por imagen , Arteria Esplénica/diagnóstico por imagen
18.
Nuklearmedizin ; 29(5): 215-20, 1990 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-2148978

RESUMEN

A new 99mTc-labelled tracer (99mTc-Sestamibi) was used for the first time to demonstrate the perfusion of the skeletal muscle. In 16 patients with obstructive atherosclerosis of the lower limbs the change of perfusion of thigh and lower leg was studied with SPECT before and after vascular surgery (n = 11) or percutaneous transluminal angioplasty (n = 5). Comparative results of scintigraphic measurements and clinical observations (ankle-arm pressure, treadmill test) in 10 surgical patients (14 operated legs) showed correct positive or negative results in 86% (12/14).


Asunto(s)
Arteriopatías Oclusivas/cirugía , Pierna/irrigación sanguínea , Músculos/irrigación sanguínea , Compuestos de Organotecnecio , Anciano , Anciano de 80 o más Años , Angioplastia de Balón , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculos/diagnóstico por imagen , Flujo Sanguíneo Regional , Tecnecio Tc 99m Sestamibi , Tomografía Computarizada de Emisión de Fotón Único
19.
Chirurg ; 55(8): 505-7, 1984 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-6488995

RESUMEN

From March 1979 through December 1983, 15 patients with soft-tissue sarcomas of the extremities were treated by a local excision and an adjuvant regional hyperthermic cytostatic perfusion. Reversible edema in two patients was the only post-operative complication. 14 patients were disease-free after a median follow-up period of 24.2 months. One female patient developed a local recurrence 10 months following surgery. Based on our results and long-term studies of several authors, the adjuvant regional perfusion appears capable of successfully treating patients with soft-tissue sarcomas of the extremities.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Brazo , Quimioterapia del Cáncer por Perfusión Regional/métodos , Pierna , Neoplasias de los Tejidos Blandos/tratamiento farmacológico , Adulto , Anciano , Terapia Combinada , Dactinomicina/administración & dosificación , Femenino , Calor , Humanos , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Neoplasias de los Tejidos Blandos/mortalidad , Neoplasias de los Tejidos Blandos/cirugía
20.
Chirurg ; 62(8): 625-8, 1991 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-1935399

RESUMEN

The subfascial discision of insufficient perforating veins is considered the most effective therapeutic principle for the treatment of postthrombotic disturbances of the skin as well as for trophic disturbances caused by varicose. A new endoscopic technique allows to be sectioned them under direct view control with little trauma. In the period from November 1986 to April 1990 61 patients underwent an endoscopic sectioning of perforating veins. Perforating veins have most frequently been separated in the area of the Cockett group (153), the 24 cm perforating vein (74) and in the area of the Boyd group (63). Two patients (3.3%) with trophic disturbances of the skin in the area of the shank showed disturbances of wound healing after the operation. First results of the follow-up examination 3-37 months postoperative have proved good (45%) to very good (40%) results. Criteria, which were observed, were pains in the leg, disturbances of sensibility, swellings and relapsed varices. Only two patients proved a bad result. Insufficient perforating veins in the area of the shank were not found by one of the 61 operated patients. Referring to a staging of chronic venous insufficiency it can be said that with the exception of the two patients above mentioned there is a ranging to a more favourable stage or to a complete treating.


Asunto(s)
Endoscopios , Instrumentos Quirúrgicos , Várices/cirugía , Insuficiencia Venosa/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología
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