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1.
Front Cardiovasc Med ; 10: 1279613, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38028463

RESUMEN

Pro-angiogenic gene therapy is being developed to treat coronary artery disease (CAD). We recently showed that bone morphogenetic protein 2 (BMP2) and vascular endothelial growth factor-A synergistically regulate endothelial cell sprouting in vitro. BMP2 was also shown to induce endocardial angiogenesis in neonatal mice post-myocardial infarction. In this study, we investigated the potential of BMP2 gene transfer to improve cardiomyocyte function and neovessel formation in a pig chronic myocardial infarction model. Ischemia was induced in domestic pigs by placing a bottleneck stent in the proximal part of the left anterior descending artery 14 days before gene transfer. Intramyocardial gene transfers with adenovirus vectors (1 × 1012 viral particles/pig) containing either human BMP2 (AdBMP2) or beta-galactosidase (AdLacZ) control gene were performed using a needle injection catheter. BMP2 transgene expression in the myocardium was detected with immunofluorescence staining in the gene transfer area 6 days after AdBMP2 administration. BMP2 gene transfer did not induce angiogenesis or cardiomyocyte proliferation in the ischemic pig myocardium as determined by the quantitations of CD31 or Ki-67 stainings, respectively. Accordingly, no changes in heart contractility were detected in left ventricular ejection fraction and strain measurements. However, BMP2 gene transfer induced pericardial effusion (AdBMP2: 9.41 ± 3.17 mm; AdLacZ: 3.07 ± 1.33 mm) that was measured by echocardiography. Furthermore, an increase in the number of immune cells and CD3+ T cells was found in the BMP2 gene transfer area. No changes were detected in the clinical chemistry analysis of pig serum or histology of the major organs, implicating that the gene transfer did not induce general toxicity, myocardial injury, or off-target effects. Finally, the levels of fibrosis and cardiomyocyte apoptosis detected by Sirius red or caspase 3 stainings, respectively, remained unaltered between the groups. Our results demonstrate that BMP2 gene transfer causes inflammatory changes and pericardial effusion in the adult ischemic myocardium, which thus does not support its therapeutic use in chronic CAD.

2.
Scand J Med Sci Sports ; 28(3): 873-880, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28975667

RESUMEN

Both athletes and coaches should have adequate nutrition knowledge to understand the importance of diet on athletic performance, recovery, and health. Nutrition knowledge can be assessed reliably only by validated knowledge questionnaires. The aim of this study was to develop a reliable and valid questionnaire for assessing the nutrition knowledge of young endurance athletes and their coaches. The questionnaire was developed with an expert panel and pilot tested by athletes, coaches, and students. Content, face, and construct validities both as test-retest reliability and internal consistency reliability were ensured when the current questionnaire was developed. Athletes (n = 16) and coaches (n = 13) pilot tested the 127-item questionnaire. After item analysis and proposals from the expert panel, 41 items were removed. Internal consistency of the 86-item questionnaire in the pilot study was 0.87, measured using Cronbach's α. Construct validity was evaluated by the difference in knowledge between nutrition (n = 20) and humanities students (n = 22). Nutrition students had significantly higher knowledge scores (P < .001). Test-retest reliability for all knowledge sections between those groups was 0.85 measured using Pearson's r. Final adjustments to the questionnaire were made on the grounds of feedback from the respondents and proposals from the experts (n = 6). These adjustments resulted in minor changes in the construct of the items, the layout of the questionnaire, and the removal of 7 items. The final questionnaire had 79 items. The questionnaire can be used to measure the overall nutrition knowledge of endurance athletes and their coaches and to find potential gaps in nutrition knowledge.


Asunto(s)
Atletas , Conocimientos, Actitudes y Práctica en Salud , Mentores , Ciencias de la Nutrición y del Deporte , Encuestas y Cuestionarios , Adolescente , Adulto , Humanos , Persona de Mediana Edad , Proyectos Piloto , Reproducibilidad de los Resultados , Estudiantes , Adulto Joven
3.
Nat Commun ; 6: 6809, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25858780

RESUMEN

Holocene summer temperature reconstructions from northern Europe based on sedimentary pollen records suggest an onset of peak summer warmth around 9,000 years ago. However, pollen-based temperature reconstructions are largely driven by changes in the proportions of tree taxa, and thus the early-Holocene warming signal may be delayed due to the geographical disequilibrium between climate and tree populations. Here we show that quantitative summer-temperature estimates in northern Europe based on macrofossils of aquatic plants are in many cases ca. 2 °C warmer in the early Holocene (11,700-7,500 years ago) than reconstructions based on pollen data. When the lag in potential tree establishment becomes imperceptible in the mid-Holocene (7,500 years ago), the reconstructed temperatures converge at all study sites. We demonstrate that aquatic plant macrofossil records can provide additional and informative insights into early-Holocene temperature evolution in northernmost Europe and suggest further validation of early post-glacial climate development based on multi-proxy data syntheses.


Asunto(s)
Organismos Acuáticos/fisiología , Fósiles , Modelos Estadísticos , Polen/fisiología , Árboles/fisiología , Clima , Simulación por Computador , Europa (Continente) , Dispersión de las Plantas/fisiología , Estaciones del Año , Temperatura
4.
J Obstet Gynaecol ; 35(1): 22-4, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25020113

RESUMEN

A prospective study was conducted to determine the outcome of pregnancies with 1st trimester nuchal translucency measurement of ≥ 6.5 mm. The risk of fetal abnormalities increases with enlarging nuchal translucency, being around 45% with a measurement of ≥ 6.5 mm. A total of 27,144 women with singleton pregnancies participated in the combined Down syndrome screening within the public healthcare system in Northern Finland. The study period was 1 May 2002 to 31 May 2009. The nuchal translucency measurement was ≥ 6.5 mm in 16 cases (0.06%). Pregnancy outcome was normal in one case (6.3%). The risk of abnormality was higher in our study than reported in the literature. According to our study, immediate diagnostic tests should be offered after an nuchal translucency measurement of ≥ 6.5 mm. We should also consider analysis of fetal micro-deletions associated with certain syndromes.


Asunto(s)
Anomalías Congénitas/diagnóstico por imagen , Medida de Translucencia Nucal , Resultado del Embarazo , Adulto , Femenino , Humanos , Embarazo , Estudios Prospectivos
5.
Acta Anaesthesiol Scand ; 49(7): 1015-22, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16045665

RESUMEN

BACKGROUND: As part of a quality assurance program, we investigated the incidence of postpartum neurologic symptoms in multiparous parturients receiving spinal block for labour analgesia, now in routine use in our labour ward. METHODS: Two hundred and twenty-nine consecutive multiparous parturients presenting for vaginal delivery and requesting spinal analgesia were asked to participate in this prospective study. All parturients received our standard intrathecal analgesia (ITA): 2.5 mg bupivacaine (1 ml) + 25 microg fentanyl (0.5 ml) using a 27-gauge Quincke-type needle. The patients filled in a questionnaire on the first day after delivery and again upon discharge. Complaints typical of neurologic sequelae were noted and a neurologic examination was performed, if necessary. All patients with postdural puncture headache (PDPH) and transient neurologic symptoms (TNSs) were interviewed by telephone 2 weeks after discharge to determine the course of the symptoms. RESULTS: Two hundred and twelve parturients were included in the study. Eighteen (8.5%) parturients complained of PDPH, the severity of which was mild in eight (4%), moderate in seven (3%), and severe in three (1%) patients, respectively. Fifteen (7%) mothers were treated with analgesics or bedrest only. Three (1%) patients were given an epidural blood patch. The paramedian approach was associated with the development of PDPH (P = 0.04). Transient neurologic symptoms were experienced by nine (4.2%) mothers, lasting 1-3 days, mostly presenting as bilateral pain in the buttocks or thighs. One parturient suffered from paraesthesia of the left foot lasting for 3 days. Forty (19%) mothers complained of non-postural headache and 28 (13%) of new-onset back pain. Three mothers (1%) would not want to receive a further spinal block. CONCLUSION: Transient neurologic symptoms (TNSs) after spinal block occurred infrequently. The incidence of PDPH was higher than in the obstetric population in general and calls for re-evaluation of our spinal block methods. Despite the occurrence of neurologic sequelae, patient acceptability was high.


Asunto(s)
Analgesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Cefalea/epidemiología , Médula Espinal/efectos de los fármacos , Adulto , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Embarazo , Estudios Prospectivos
6.
Acta Anaesthesiol Scand ; 49(7): 1023-9, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16045666

RESUMEN

BACKGROUND: Intrathecal analgesia (ITA) is effective in late, rapidly progressing labour. In 1998, our hospital implemented the use of single-shot spinal block for pain relief in multiparous parturients. As part of a quality assurance programme, we assessed the analgesic efficacy, obstetric and neonatal outcomes and maternal satisfaction after this form of analgesia now in routine use in our labour ward. METHODS: Two hundred and twenty-nine consecutive multiparous parturients presenting for vaginal delivery and requesting analgesia were asked to participate in this prospective study. All parturients received our standard ITA: 2.5 mg bupivacaine (1 ml) + 25 microg fentanyl (0.5 ml) inserted via the L2-3 or L3-4 interspace. Routine monitoring included maternal vital signs, uterine contraction and fetal heart rate tracing. Pain scores (visual analogue scale (VAS) 0-10), sensory levels, motor block, side-effects and maternal satisfaction were recorded. Satisfactory analgesia was defined as a decrease in pain scores to three or less within 20 min after injection. The number of parturients requesting additional analgesia and the duration of spinal block (time from injection until request for additional medication after satisfactory analgesia had worn off) were recorded. RESULTS: Two hundred and nine parturients were included in the study. Satisfactory analgesia was achieved in 153 (73%) parturients. Fifty-five (26%) women requested additional analgesia: 38 (18%) because of unsatisfactory analgesia and 17 (8%) because analgesia ended before delivery. The duration of spinal block was 101 +/- 34 min. Pruritus occurred in 64%, fetal bradycardia in 7% and hypotension in 2% of deliveries. Pain relief was rated excellent by 65%, moderate by 20% and inadequate by 14% of the parturients. One hundred and sixty-nine (81%) women stated that they would like to have spinal analgesia again for pain relief during delivery. CONCLUSION: The majority of multiparous parturients found ITA adequate for pain relief during delivery. However, modifications are required in terms of improved timing, reliability and duration of analgesia.


Asunto(s)
Analgesia Obstétrica/métodos , Anestesia Raquidea/métodos , Adulto , Analgesia Epidural , Analgesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Estudios Prospectivos
7.
J Clin Endocrinol Metab ; 88(11): 5180-5, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14602747

RESUMEN

Phytoestrogens are thought to be beneficial to vascular health. Possible mechanisms of action could involve C-reactive protein (CRP), endothelial E-selectin, and nitric oxide. We therefore designed a randomized, placebo-controlled, double-blind trial in which we studied the effects of isoflavonoids on CRP, E-selectin, and nitrate-nitrite (NO(x); reflecting the release of nitric oxide) in postmenopausal women. Fifty-six postmenopausal women (FSH > 30 U/liter) with a history of breast cancer used (in a randomized order) phytoestrogen (114 mg isoflavonoids) or placebo tablets daily for 3 months; the treatment regimens were crossed over after a 2-month washout period. The serum levels of CRP and E-selectin, and plasma levels of NO(x) were measured before and on the last day of each treatment. The phytoestrogen regimen did not affect the levels of either CRP (P = 0.584) or NO(x) (P = 0.270), but the levels of E-selectin were reduced by 4.0% (2.9 ng/ml; P = 0.031) during phytoestrogen use and by 2.2% (1.3 ng/ml; P = 0.023) during placebo use. No difference was found at any marker at 3 months between the groups. In conclusion, our data, suggesting neutral effects of phytoestrogens on CRP, E-selectin, and nitric oxide, fail to support a vasoprotective role of phytoestrogens.


Asunto(s)
Proteína C-Reactiva/metabolismo , Selectina E/sangre , Isoflavonas/administración & dosificación , Nitratos/sangre , Fitoterapia , Preparaciones de Plantas/administración & dosificación , Adulto , Anciano , Neoplasias de la Mama , Estudios Cruzados , Estrógenos no Esteroides/administración & dosificación , Estrógenos no Esteroides/sangre , Femenino , Humanos , Isoflavonas/sangre , Persona de Mediana Edad , Fitoestrógenos , Preparaciones de Plantas/sangre
8.
J Appl Microbiol ; 95(3): 471-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12911694

RESUMEN

AIMS: To study the bacterial diversity in expressed human milk with a focus on detecting bacteria with an antimicrobial activity against Staphylococcus aureus, known as a causative agent of maternal breast infections and neonatal infections. METHODS AND RESULTS: Random isolates (n = 509) were collected from breast milk samples (n = 40) of healthy lactating women, genotypically identified, and tested for antimicrobial activity against Staph. aureus. Commensal staphylococci (64%) and oral streptococci (30%), with Staph. epidermidis, Strep. salivarius, and Strep. mitis as the most frequent isolates, were the predominant bacterial species in breast milk. One-fifth of Staph. epidermidis and half of Strep. salivarius isolates suppressed growth of Staph. aureus. Enterococci (Ent. faecalis), isolated from 7.5% of samples, and lactic acid bacteria (LAB) (Lactobacillus rhamnosus, Lact. crispatus, Lactococcus lactis, Leuconoctoc mesenteroides), isolated from 12.5% of samples, were also effective against Staph. aureus. One L. lactis isolate was shown to produce nisin, a bacteriocin used in food industry to prevent bacterial pathogens and spoilage. CONCLUSIONS: Expressed breast milk contains commensal bacteria, which inhibit Staph. aureus. SIGNIFICANCE AND IMPACT OF THE STUDY: The strains inhibitory against the pathogen Staph. aureus have potential use as bacteriotherapeutic agents in preventing neonatal and maternal breast infections caused by this bacterium.


Asunto(s)
Antibiosis , Microbiología de Alimentos , Leche Humana/microbiología , Staphylococcus aureus/crecimiento & desarrollo , Bacterias/clasificación , Bacterias/aislamiento & purificación , Técnicas de Tipificación Bacteriana/métodos , Recuento de Colonia Microbiana , Humanos , Lactococcus lactis/metabolismo , Nisina/biosíntesis , Staphylococcus aureus/aislamiento & purificación
9.
Int J Tuberc Lung Dis ; 7(1): 22-9, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12701831

RESUMEN

SETTING: Mycobacterium bovis bacille Calmette-Guerin (BCG) is provided to all infants born in Finland. OBJECTIVE: To analyze the cost-effectiveness of universal versus selective BCG immunization. DESIGN: A Markov model was developed to simulate rates of tuberculosis (TB) and non-tuberculous mycobacterial disease (NTM), and to examine the cost-effectiveness in terms of cost per case averted of three different strategies: universal BCG, selective BCG (10% of infants at higher TB risk than other infants) or no BCG immunization. RESULTS: In a cohort of 60,000 infants over 15 years, the model predicts five cases each of TB and NTM disease with universal immunization, 8-21 TB and 31 NTM cases with various strategies of selective immunization, and 25 TB and 34 NTM cases with no BCG immunization. BCG side-effects are predicted in 5, 0.5 and 0 infants, respectively. The cost per case averted for immunization strategies ranges from a cost of 38,311 US dollars to a savings of 323 dollars as selective immunization becomes more efficient at targeting infants at highest risk of TB. CONCLUSIONS: In a country with a low incidence of pediatric tuberculosis, selective BCG immunization is a more cost-effective strategy than universal BCG immunization for the prevention of tuberculosis, but results in an increase in NTM cases.


Asunto(s)
Vacuna BCG/economía , Programas de Inmunización/economía , Selección de Paciente , Tuberculosis/prevención & control , Vacuna BCG/administración & dosificación , Estudios de Cohortes , Costo de Enfermedad , Análisis Costo-Beneficio , Finlandia/epidemiología , Humanos , Programas de Inmunización/organización & administración , Incidencia , Lactante , Cadenas de Markov , Vacunación Masiva/economía , Tuberculosis/epidemiología
10.
Gynecol Endocrinol ; 16(6): 469-78, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12626034

RESUMEN

Health care professionals in modern Western societies will meet an increasing number of women surviving breast cancer. How the menopause of these women should be treated is still an open question. Use of hormone replacement therapy (HRT) may, at least in theory, increase the risk for recurrence of cancer, but its categoric refusal is a double-edged sword because it also denies these women all the undisputable health benefits HRT provides. This refusal is not, however, supported by the observational data available so far on this question, because HRT has not increased the risk for breast cancer recurrence. In fact, it is well established that HRT abolishes hot flushes and improves significantly these patients' quality of life. At present, we have no effective nonhormonal alternatives for the control of vasomotor symptoms, and the efficacy of phytoestrogens in the treatment of menopausal symptoms is unproven. Selective estrogen receptor modulators (SERMs) which protect against osteoporosis and perhaps also against breast cancer, and which may have beneficial effects on the cardiovascular system, aggravate hot flushes and are therefore not useful, at least in the first postmenopausal years. In some countries, progestins are often prescribed for the control of such patients' vasomotor symptoms, but their safety has never been assessed in clinical trials, and in theory they can be harmful. Randomized clinical trials (RCT) on the use of HRT in breast cancer survivors are underway, but their completion will take years, and even these may be open to criticism. Tibolone may appear to be an appealing alternative for HRT, but it should also be studied with RCTs in this indication. At present, a patient with a history of breast cancer must be given balanced information as to the possible benefits and risks of HRT, and she herself must make the decision whether or not to start HRT.


Asunto(s)
Neoplasias de la Mama , Terapia de Reemplazo de Estrógeno , Menopausia , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/etiología , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Sofocos , Humanos , Recurrencia Local de Neoplasia , Norpregnenos , Calidad de Vida , Factores de Riesgo , Moduladores Selectivos de los Receptores de Estrógeno
11.
J Exp Zool ; 290(6): 616-23, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11748610

RESUMEN

Wnts are intercellular growth and differentiation factors that regulate several key developmental steps, such as gastrulation, neurulation, and organogenesis, including the development of the midbrain, central nervous system, kidney, and limbs. Wnts are also needed for a normal development of the reproductive system. Deficiency of Wnt-4, -5a, and -7a, for example, results in sex reversal, infertility, and/or malformation of the internal and external genitals. Here we focus on the importance of Wnts in the female reproductive system.


Asunto(s)
Mama/crecimiento & desarrollo , Genitales Femeninos/crecimiento & desarrollo , Conductos Paramesonéfricos/crecimiento & desarrollo , Proteínas Proto-Oncogénicas/farmacología , Diferenciación Sexual/fisiología , Animales , Diferenciación Celular , Drosophila , Femenino , Humanos , Oocitos/fisiología , Fenotipo , Proteínas Proto-Oncogénicas/biosíntesis , Conejos , Transducción de Señal , Proteínas Wnt , Proteína Wnt-5a , Proteína Wnt4
13.
Psychopharmacology (Berl) ; 156(4): 402-9, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11498717

RESUMEN

RATIONALE: L-Dopa induces dyskinesias during the treatment of Parkinson's disease and also in primates with nigrostriatal lesions produced by MPTP, but it is claimed that L-dopa does not provoke dyskinesia in humans or monkeys with an intact or mildly damaged nigrostriatal system. OBJECTIVES: This study assessed the behavioural and pharmacokinetic effects of chronic oral administration of L-dopa plus carbidopa alone, or with co-administration of the peripheral COMT inhibitor entacapone, to normal macaque monkeys. Repeated high dose L-dopa administration was shown to induce marked dyskinesias in monkeys with an intact nigrostriatal system, and the threshold for dyskinesia expression was increased by peripheral catechol-O-methyltransferase inhibition with entacapone. METHODS: Six groups of normal macaque monkeys (n=8 per group; Macaca fascicularis) were treated with L-dopa (20, 40 or 80 mg/kg) plus carbidopa (5, 10 or 20 mg/kg) with or without the catechol-O-methyltransferase inhibitor entacapone (20, 40 or 80 mg/kg), or with entacapone alone (80 mg/kg), by oral administration once daily for 13 weeks. RESULTS: Eleven of 16 animals receiving high dose L-dopa (80 mg/kg plus carbidopa 20 mg/kg PO with or without entacapone 80 mg/kg PO for 13 weeks) gradually developed reproducible and idiosyncratic combinations of chorea, athetosis and dystonia maximal at 60-100 min after L-dopa administration, which progressively intensified over the course of the study. The dyskinesias observed were similar in type and distribution to L-dopa-induced dyskinesia observed in patients with Parkinson's disease and in MPTP-treated primates. The occurrence of dyskinesia correlated with plasma concentrations of L-dopa, with animals displaying the most severe dyskinesias having significantly higher plasma concentrations of L-dopa one hour after dosing than animals with mild or moderate dyskinesia or no dyskinesia. Co-administration of entacapone with L-dopa plus carbidopa significantly lowered peak plasma concentrations of L-dopa and this was reflected by a decrease in the severity of dyskinesias, with only one animal receiving entacapone and high dose L-dopa plus carbidopa showing severe dyskinesia, while four receiving high dose L-dopa plus carbidopa alone did so. CONCLUSIONS: These results show for the first time that chronic oral L-dopa administration can provoke dyskinesias in primates independently of nigrostriatal damage, and that this effect is dose related.


Asunto(s)
Dopaminérgicos/farmacocinética , Discinesia Inducida por Medicamentos/metabolismo , Levodopa/farmacocinética , Trastornos del Movimiento , Animales , Conducta Animal/efectos de los fármacos , Dopaminérgicos/sangre , Dopaminérgicos/farmacología , Relación Dosis-Respuesta a Droga , Discinesia Inducida por Medicamentos/sangre , Femenino , Levodopa/sangre , Levodopa/farmacología , Macaca fascicularis , Masculino , Trastornos del Movimiento/sangre , Trastornos del Movimiento/metabolismo
14.
J Appl Microbiol ; 90(6): 850-8, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11412314

RESUMEN

AIMS: Enumeration of coliform bacteria and Escherichia coli is the most widely used method in the estimation of hygienic quality of drinking water. The yield of target bacteria and the species composition of different populations of coliform bacteria may depend on the method.Three methods were compared. METHODS AND RESULTS: Three membrane filtration methods were used for the enumeration of coliform bacteria in shallow well waters. The yield of confirmed coliform bacteria was highest on Differential Coliform agar, followed by LES Endo agar. Differential Coliform agar had the highest proportion of typical colonies, of which 74% were confirmed as belonging to the Enterobacteriaceae. Of the typical colonies on Lactose Tergitol 7 TTC agar, 75% were confirmed as Enterobacteriaceae, whereas 92% of typical colonies on LES Endo agar belonged to the Enterobacteriaceae. LES Endo agar yielded many Serratia strains, Lactose Tergitol 7 TTC agar yielded numerous strains of Rahnella aquatilis and Enterobacter, whereas Differential Coliform agar yielded the widest range of species. CONCLUSION: The yield of coliform bacteria varied between methods. Each method compared had a characteristic species distribution of target bacteria and a typical level of interference of non-target bacteria. Identification with routine physiological tests to distinct species was hampered by the slight differences between species. High yield and sufficient selectivity are difficult to achieve simultaneously, especially if the target group is diverse. SIGNIFICANCE AND IMPACT OF THE STUDY: The results showed that several aspects of method performance should be considered, and that the target group must be distinctly defined to enable method comparisons.


Asunto(s)
Técnicas Bacteriológicas , Enterobacteriaceae/clasificación , Enterobacteriaceae/aislamiento & purificación , Microbiología del Agua , Abastecimiento de Agua , Técnicas de Tipificación Bacteriana , Recuento de Colonia Microbiana , Ingestión de Líquidos , Estándares de Referencia , Reproducibilidad de los Resultados , Manejo de Especímenes
15.
J Bacteriol ; 183(5): 1663-71, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11160097

RESUMEN

By transforming N2O to N2, the multicopper enzyme nitrous oxide reductase provides a periplasmic electron sink for a respiratory chain that is part of denitrification. The signal sequence of the enzyme carries the heptameric twin-arginine consensus motif characteristic of the Tat pathway. We have identified tat genes of Pseudomonas stutzeri and functionally analyzed the unlinked tatC and tatE loci. A tatC mutant retained N2O reductase in the cytoplasm in the unprocessed form and lacking the metal cofactors. This is contrary to viewing the Tat system as specific only for fully assembled proteins. A C618V exchange in the electron transfer center CuA rendered the enzyme largely incompetent for transport. The location of the mutation in the C-terminal domain of N(2)O reductase implies that the Tat system acts on a completely synthesized protein and is sensitive to a late structural variation in folding. By generating a tatE mutant and a reductase-overproducing strain, we show a function for TatE in N2O reductase translocation. Further, we have found that the Tat and Sec pathways have to cooperate to produce a functional nitrite reductase system. The cytochrome cd1 nitrite reductase was found in the periplasm of the tatC mutant, suggesting export by the Sec pathway; however, the enzyme lacked the heme D1 macrocycle. The NirD protein as part of a complex required for heme D1 synthesis or processing carries a putative Tat signal peptide. Since NO reduction was also inhibited in the tatC mutant, the Tat protein translocation system is necessary in multiple ways for establishing anaerobic nitrite denitrification.


Asunto(s)
Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Citocromos/biosíntesis , Proteínas de Escherichia coli , Proteínas de Transporte de Membrana , Nitrito Reductasas/biosíntesis , Oxidorreductasas/metabolismo , Pseudomonas/metabolismo , Secuencia de Aminoácidos , Proteínas Portadoras/química , Cobre/metabolismo , Medios de Cultivo , Grupo Citocromo c , Genes Bacterianos , Datos de Secuencia Molecular , Mutación , Nitratos/metabolismo , Nitritos/metabolismo , Consumo de Oxígeno , Pseudomonas/genética , Pseudomonas/crecimiento & desarrollo , Análisis de Secuencia de ADN
16.
Endocrinology ; 141(7): 2631-7, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10875268

RESUMEN

The final step in the biosynthesis of testosterone is reduction of androstenedione by the enzyme 17beta-hydroxysteroid dehydrogenase/ 17-ketosteroid reductase (17betaHSD/17KSR). In this study, we have examined expression of the four known reductive isoforms of 17betaHSD/ 17KSR (types 1, 3, 5, and 7) in the developing mouse testis and have determined changes in the localization of isoform expression and testosterone secretion during development. Using RT-PCR isoforms 1, 3, and 7 were shown to be expressed in the seminiferous tubules of neonatal testis, whereas isoforms 3 and 7 were expressed in the interstitial tissue of the adult testis. The type 7 isoform is unlikely to be involved in androgen synthesis and further study concentrated on the type 3 isoform. Developmentally, isoform type 3 was expressed in the seminiferous tubules up to day 10, showed little or no expression on day 20 and from day 30 was confined to the interstitial tissue. In situ hybridization confirmed that the type 3 isoform was expressed only in the seminiferous tubules in fetal testes and in the interstitial tissue in adult testes. In accordance with the localization of enzyme messenger RNA expression 17-ketosteroid reductase enzyme activity was very low in isolated interstitial tissue from neonatal testes while interstitial tissue from adult testes showed high activity. Seminiferous tubules from both neonatal and adult testes showed high levels of enzyme activity. The major androgen secreted by the interstitial tissue of prepubertal animals was androstenedione up to day 20 while 5alpha-androstanediol and/or testosterone were the major androgens secreted from day 30 onwards. These results show that fetal Leydig cells do not express significant levels of a reductive isoform of 17betaHSD/ 17KSR and that androstenedione is the major androgen secreted by these cells. Production of testosterone up until puberty is dependent upon 17betaHSD/17KSR activity in the seminiferous tubules--a "two cell" requirement for testosterone synthesis. Expression of the 17betaHSD/17KSR type 3 isoform (the main reductive isoform in the testis) declines in the seminiferous tubules before puberty but then reappears in the developing adult Leydig cell population.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/metabolismo , Envejecimiento/metabolismo , Animales Recién Nacidos/metabolismo , Feto/metabolismo , Isoenzimas/metabolismo , Testículo/enzimología , Andrógenos/biosíntesis , Androstenodiona/metabolismo , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Desarrollo Embrionario y Fetal , Hibridación in Situ , Técnicas In Vitro , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Ratones Endogámicos C3H , Testículo/citología , Testículo/embriología , Testículo/crecimiento & desarrollo , Distribución Tisular
17.
Acta Oncol ; 39(8): 969-72, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11207004

RESUMEN

The aim of the study was to find out whether the effect of hormonal replacement therapy (HRT) is modified by the mammographic parenchymal patterns on the risk of breast cancer. Subjects were 4163 Finnish women aged 40-47 years at entry who were invited to breast cancer screening every second year from 1982 to 1990. Mammographic parenchymal patterns (Wolfe's classification) were recorded at each screening round. The information, on use of HRT, was recorded from 1984. The follow-up ended in 1993 and up until that time 68 new breast cancers were diagnosed. A Poisson regression model was used in the analysis of the data. Use of HRT was not related to the risk of breast cancer (RR = 0.7, 95% CI 0.4-1.4), whereas mammographic parenchymal pattern was statistically significantly associated with risk of breast cancer. The age-adjusted relative risk of breast cancer among women with P2 versus N1 pattern was 2.5 (95% CI 1.3-4.8) and with DY versus N1 pattern 4.9 (951% CI 1.6-15.1). Women using HRT and with DY pattern were at substantially increased risk of breast cancer (RR = 11.6, 95% CI 2.5-53.6) compared with women not using HRT and with N1 pattern. There was an increased risk of breast cancer among women with DY mammographic parenchymal pattern who used HRT, which was consistent with a synergistic joint effect.


Asunto(s)
Mama/anatomía & histología , Terapia de Reemplazo de Hormonas , Adulto , Factores de Edad , Mama/efectos de los fármacos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Contraindicaciones , Femenino , Terapia de Reemplazo de Hormonas/efectos adversos , Humanos , Incidencia , Mamografía , Tamizaje Masivo , Persona de Mediana Edad , Proyectos Piloto , Distribución de Poisson , Factores de Riesgo
18.
Breast Cancer Res Treat ; 57(2): 165-73, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10598043

RESUMEN

The purpose of the study was to estimate the incidence of unfavourable mammographic pattern by risk factors of breast cancers. Data consisted of 1890 Finnish women with mammographic pattern of either N1 or P1 (Wolfe's classification) at the initial screening. The screening was repeated every second year from 1982 to 1990 and at each screening round the mammographic pattern was assessed. The incidence rate of P2,DY pattern was 1.9/100 woman years. The incidence of P2,DY pattern was significantly related to age. The age-adjusted odds ratio (OR) (based on logistic regression) was 2.0 (95% CI 1.0-3.9) among women with hormonal replacement therapy (HRT), 0.6 (95% CI 0.4-0.9) among postmenopausal women, 0.2 (95% CI 0.1-0.4) among women with large breasts and 0.2 (95% CI 0.1-0.3) among women with large body mass index (BMI). After multivariate adjustment by logistic regression only the effect of BMI remained statistically significant, odds ratio of P2,DY pattern for women with BMI 25 or more was 0.2 (95% CI 0.1-0.6) compared to women with BMI less than 20.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Adulto , Factores de Edad , Femenino , Finlandia/epidemiología , Terapia de Reemplazo de Hormonas , Humanos , Incidencia , Modelos Logísticos , Mamografía , Menopausia , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo
20.
J Biomater Sci Polym Ed ; 10(7): 715-28, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10426228

RESUMEN

A novel composite material with an ultra-high strength and a low elastic modulus, comprising a carbon fibre reinforced liquid crystalline polymer (LCP/CF) has been developed. An experimental osteotomy of the distal femur in nineteen rabbits weighing on average 4.8 (3.7-6.3) kg was fixed with an intramedullary LCP/CF rod of 3.2 mm in diameter and 50 mm in length. The initial mechanical properties of the rods had a mean shear strength of 180 MPa, a flexural strength of 450 MPa, and a flexural modulus of 40 GPa. The rods were implanted for periods of 3, 6, 12, 24, and 52 weeks. The healing of the osteotomy was analyzed by radiographic, histological, microradiographic, and oxytetracycline fluorescence studies. The strength retention of the LCP/CF rods was measured by mechanical testing. Solid union of the osteotomy was seen within 6 weeks. The implants retained their original strength properties up to 52 weeks. In three rabbits, a non-union with granulation tissue and carbon fibre particles was noticed at the osteotomy site, where disruption of the implant surface was seen at the level of the osteotomy. Further studies with a special interest in the fabrication process of the LCP/CF-implants are needed.


Asunto(s)
Materiales Biocompatibles , Carbono , Fémur/cirugía , Fijadores Internos , Animales , Falla de Equipo , Femenino , Masculino , Osteotomía , Conejos
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