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1.
Water Sci Technol ; 71(9): 1354-60, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25945852

RESUMEN

As a result of their mode of filter feeding, zebra mussels (Dreissena polymorpha Pall.) have been observed to purify natural water bodies and in vitro. Therefore, the possibility of using zebra mussels for water purification was investigated in a slightly brackish water body of a large lagoon. In this study, water samples were taken above, near and at distance from zebra mussel beds (MB) in the Odra Lagoon in North East Germany. Near typical bacterial species like Aeromonas spp. pathogenic bacteria with potential relation to hospital wastewater pollution (Burkholderia cepacia, Staphylococcus aureus, Weeksella spp.) were detected. There were no correlations found between either total bacteria or pathogens and distance to MB and no antimicrobial effect of the mussels could be deduced. For bioremediation in larger water bodies like lagoons, natural zebra MB do not seem to play a major antimicrobial role and the effect of artificial mussel grids especially against hospital pathogens should be investigated.


Asunto(s)
Dreissena/fisiología , Microbiología del Agua , Animales , Bivalvos , Filtración , Staphylococcus aureus/aislamiento & purificación , Purificación del Agua
2.
Nat Genet ; 25(4): 419-22, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10932186

RESUMEN

The autosomal recessive form of Robinow syndrome (RRS; MIM 268310) is a severe skeletal dysplasia with generalized limb bone shortening, segmental defects of the spine, brachydactyly and a dysmorphic facial appearance. We previously mapped the gene mutated in RRS to chromosome 9q22 (ref. 4), a region that overlaps the locus for autosomal dominant brachydactyly type B (refs 5,6). The recent identification of ROR2, encoding an orphan receptor tyrosine kinase, as the gene mutated in brachydactyly type B (BDB1; ref. 7) and the mesomelic dwarfing in mice homozygous for a lacZ and/or a neo insertion into Ror2 (refs 8,9) made this gene a candidate for RRS. Here we report homozygous missense mutations in both intracellular and extracellular domains of ROR2 in affected individuals from 3 unrelated consanguineous families, and a nonsense mutation that removes the tyrosine kinase domain and all subsequent 3' regions of the gene in 14 patients from 7 families from Oman. The nature of these mutations suggests that RRS is caused by loss of ROR2 activity. The identification of mutations in three distinct domains (containing Frizzled-like, kringle and tyrosine kinase motifs) indicates that these are all essential for ROR2 function.


Asunto(s)
Anomalías Múltiples/genética , Deformidades Congénitas de las Extremidades/genética , Receptores de Superficie Celular/genética , Anomalías Múltiples/patología , Alelos , ADN/química , ADN/genética , Análisis Mutacional de ADN , Cara/anomalías , Genes Dominantes , Genes Recesivos , Humanos , Deformidades Congénitas de las Extremidades/patología , Datos de Secuencia Molecular , Mutación , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple , Proteínas Tirosina Quinasas Receptoras/genética , Receptores Huérfanos Similares al Receptor Tirosina Quinasa , Sindactilia , Síndrome
3.
Circulation ; 100(10): 1077-84, 1999 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-10477533

RESUMEN

BACKGROUND: Long-QT syndrome is a monogenic disorder that produces cardiac arrhythmias and can lead to sudden death. At least 5 loci and 4 known genes exist in which mutations have been shown to be responsible for the disease. The potassium channel gene KCNQ1, previously named KVLQT1, on chromosome 11p15.5 is one of these. METHODS AND RESULTS: We initially analyzed one family using microsatellite markers and found linkage to KCNQ1. Mutation detection showed a G to C change in the last base of exon 6 (1032 G-->C) that does not alter the coded alanine. Restriction digest analysis in the family showed that only affected individuals carried the mutation. A previous report suggested that a G to A substitution at the same position may act as a splice mutation in KCNQ1, but no data was given to support this hypothesis nor was the transcription product identified. We have shown by reverse-transcription polymerase chain reaction that 2 smaller bands were produced for the KCNQ1 gene transcripts in addition to the normal-sized transcripts when lymphocytes of affected individuals were analyzed. Sequencing these transcripts showed a loss of exon 7 in one and exons 6 and 7 in the other, but an in-frame transcript was left in each instance. We examined other families in whom long-QT syndrome was diagnosed and found another unreported splice-site mutation, 922-1 G-->C, in the acceptor site of intron 5, and 2 of the previously reported 1032 G-->A mutations. All these showed a loss of exons 6 and 7 in the mutant transcripts, validating the proposal that a consensus sequence is affected in the exonic mutations and that the integrity of the base at position 1032 is essential for correct processing of the transcript. CONCLUSIONS: The 6 cases already reported in the literature with the 1032 G-->A transition, the novel 1032 G-->C transversion, and a recent G-->T transversion at the same base show that codon 344 is the second most frequently mutated after codon 341, suggesting at least two hotspots for mutations in KCNQ1.


Asunto(s)
ADN Recombinante/genética , Síndrome de QT Prolongado/genética , Mutación/genética , Canales de Potasio con Entrada de Voltaje , Canales de Potasio/genética , Preescolar , Codón/genética , Humanos , Canales de Potasio KCNQ , Canal de Potasio KCNQ1 , Masculino , Repeticiones de Microsatélite , Linaje , Sistemas de Lectura/genética , Transcripción Genética
4.
J Med Chem ; 19(2): 219-22, 1976 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1249802

RESUMEN

Aliphatic analogs of 2,8-dibenzylcyclooctanone which includes C15-C18 ketones have been investigated for hypocholesterolemic activity in rats. The position of the carbonyl group in the chain for maximum activity appears to be the 2 position. 2-Hexadecanone reduced serum cholesterol levels significantly without altering serum triglyceride levels. This drug was not estrogenic at effective doses which is in contrast to the cyclooctanones which possess this activity.


Asunto(s)
Anticolesterolemiantes/síntesis química , Cetonas/síntesis química , Animales , Anticolesterolemiantes/farmacología , Peso Corporal/efectos de los fármacos , Castración , Membrana Celular/efectos de los fármacos , Colesterol/sangre , ADN/metabolismo , Ingestión de Alimentos/efectos de los fármacos , Femenino , Cetonas/farmacología , Metabolismo de los Lípidos , Hígado/metabolismo , Hígado/ultraestructura , Glucógeno Hepático/metabolismo , Lisosomas/efectos de los fármacos , Masculino , Ratones , Ovario/fisiología , Proteínas/metabolismo , ARN/metabolismo , Ratas , Triglicéridos/sangre , Útero/efectos de los fármacos
5.
J Histochem Cytochem ; 46(7): 855-61, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9632745

RESUMEN

We investigated carbonic anhydrase IV (CA IV) in rat and human heart with immunohistochemical methods by both light and electron microscopy. In cryosections that were incubated with anti-CA IV/FITC, the capillaries showed a strong reaction for CA IV. In paraffin and semithin sections treated with anti-CA IV/ABC (avidin-biotin-peroxidase complex) blood vessels, capillaries, and sarcolemma (SL) were positively stained. By staining ultrathin sections with anti-CA IV/immunogold, CA IV could also be demonstrated at the latter two locations, including the specialized sarcolemmal structures intercalated discs, and T-tubules. In addition, by this method CA IV was seen to be associated with the sarcoplasmic reticulum (SR). The absence of immunostaining in SR and/or SL with some techniques probably indicates a problem of accessibility of the antigenic sites. In line with the immunohistochemical results, CA IV mRNA expression was visualized in both endothelial and muscle cells by in situ hybridization histochemistry.


Asunto(s)
Anhidrasas Carbónicas/análisis , Miocardio/química , Animales , Endotelio Vascular/química , Endotelio Vascular/ultraestructura , Técnica del Anticuerpo Fluorescente Directa , Humanos , Inmunohistoquímica , Hibridación in Situ , Músculo Esquelético/química , Miocardio/ultraestructura , ARN Mensajero/análisis , Ratas , Sarcolema/química , Sarcolema/ultraestructura , Retículo Sarcoplasmático/química , Retículo Sarcoplasmático/ultraestructura
6.
Peptides ; 19(8): 1309-16, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9809644

RESUMEN

Estradiol benzoate (10 microg EB) given to ovariectomized-adrenalectomized rats induced sexual receptivity in half the animals and increased alpha-MSH in the preoptic area, ventromedial nucleus (VMN) and arcuate nucleus (ARC), in all the animals, although levels were significantly higher in the VMN and ARC of the receptive (R) subgroup. EB also raised levels of beta-endorphin in the VMN and ARC in the R rats only. POMC expression was not altered. EB did not affect alphaMSH in extra-hypothalamic areas, but addition of progesterone, raised levels in the septum, amygdala, hippocampus and caudate putamen. Only in the VMN, ARC and septum were the steroid-induced increases correlated with onset of sexual behavior.


Asunto(s)
Hormonas Esteroides Gonadales/fisiología , Proopiomelanocortina/fisiología , Conducta Sexual Animal/fisiología , alfa-MSH/fisiología , betaendorfina/fisiología , Animales , Núcleo Arqueado del Hipotálamo/química , Núcleo Arqueado del Hipotálamo/fisiología , Northern Blotting , Estradiol/farmacología , Femenino , Masculino , Postura/fisiología , Área Preóptica/química , Área Preóptica/fisiología , Proopiomelanocortina/biosíntesis , Progesterona/farmacología , ARN Mensajero/análisis , Radioinmunoensayo , Ratas , Ratas Wistar , Tabique Pelúcido/química , Tabique Pelúcido/fisiología , Conducta Sexual Animal/efectos de los fármacos , Núcleo Hipotalámico Ventromedial/química , Núcleo Hipotalámico Ventromedial/fisiología , alfa-MSH/biosíntesis , betaendorfina/biosíntesis
7.
Int J Hyg Environ Health ; 204(2-3): 157-63, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11759159

RESUMEN

Acute toxicity of heavy metals and organic pollutants was examined using Rhabditis oxycerca (Nematoda) and Paramecium spec. (Protozoa, Ciliata) as indicator organisms. The substances tested were based on the composition found in the river Odra. They were used in graduated dilution series (1000-fold, 500-, 250-, 167-, 125-, 100-, and 83-fold of the Odra concentration). In a special apparatus with an electric field the animals were induced to migrate from the anode to the cathode. Their migration activity (distance) and the number of migrating animals were influenced by the substances tested. To assess the extent of damage, results were compared with controls (tap water) and reference substances (aldicarb and chloracetamide). The investigations showed that heavy metal concentrations > 100-fold of the Odra concentration led to behavioural changes of both test organisms. The organic pollutants, in contrast, did not cause detectable changes in ciliates and only led to slight reductions in the migration activity of nematodes, without concentration-dependent gradations.


Asunto(s)
Metales Pesados/toxicidad , Movimiento , Paramecium , Rhabditoidea , Contaminantes Químicos del Agua/toxicidad , Animales , Conducta Animal , Relación Dosis-Respuesta a Droga , Electricidad , Compuestos Orgánicos/toxicidad , Pruebas de Toxicidad/métodos
8.
Int J Hyg Environ Health ; 203(5-6): 417-33, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11556146

RESUMEN

The exceptional flood of the river Odra in July/August 1997 caused severe damage, especially on the Polish side of the Odra valley. An additional 5 km3 of water were discharged during the flood. This represents about a third of the normal annual Odra discharge of 17 km3. Large agricultural and industrial areas were submerged, as well as towns and villages. However, as regards the Odra lagoon and the beaches of the Isle of Usedom, the substances transported, such as nutrients and pollutants, did not cause much damage, due to strong dilution. Hygienic investigations (human pathogenic bacteria and viruses) showed that the water had bathing quality during the whole flood.


Asunto(s)
Desastres , Monitoreo del Ambiente , Contaminantes Ambientales/efectos adversos , Abastecimiento de Agua , Agricultura , Bacterias , Humanos , Industrias , Tamaño de la Partícula , Plaguicidas , Polonia , Salud Pública , Virus
9.
Int J Oral Maxillofac Surg ; 33(6): 558-63, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15308255

RESUMEN

The aim of the present study was to assess the results after transplantation of 85 immature third molars. Recipient site conditions varied and different surgical techniques were used. The long-term results after preparation of a new alveolus, splitting osteotomy of the alveolar process or use of free bone autografts were compared with the results after transplantation into a fresh extraction site (control group). Transplantations into prepared sockets showed equal results to the control group (94% respectively). Transplantations in connection with free bone autografts (84%) or after splitting osteotomy of the alveolar process (63%) showed poorer success rates, the differences between the latter and the control group being statistically significant. A possible correlation to revascularization disturbances of the pulp due to an insufficiency of the recipient site or to postoperative infection is suspected. The results show that transplantation of immature third molars is a safe, useful procedure when appropriate conditions of the recipient site are present. Where the alveolus is atrophic, a splitting osteotomy should be performed only in exceptional cases and preference should be given to alternative methods such as primary bone augmentation or bone-regenerative procedures.


Asunto(s)
Arcada Parcialmente Edéntula/cirugía , Tercer Molar/trasplante , Germen Dentario/trasplante , Adolescente , Adulto , Pérdida de Hueso Alveolar/cirugía , Aumento de la Cresta Alveolar/efectos adversos , Aumento de la Cresta Alveolar/métodos , Trasplante Óseo , Necrosis de la Pulpa Dental/etiología , Femenino , Humanos , Masculino , Tercer Molar/crecimiento & desarrollo , Osteotomía/efectos adversos , Osteotomía/métodos , Ferulas Periodontales , Resorción Radicular/etiología , Movilidad Dentaria , Raíz del Diente/crecimiento & desarrollo , Alveolo Dental/cirugía , Trasplante Autólogo/métodos , Resultado del Tratamiento
10.
Braz Dent J ; 11(1): 19-27, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11210270

RESUMEN

A high-grade steel model with different preparation angles of 3 degrees, 7 degrees and 11 degrees in one- and two-step impression techniques were made for the determination of the influence of the preparation angle on the dimension loyalty of the resulting master casts. Using a 3-D-measuring instrument, analysis of the data showed that with the correction technique the model abutments led to a reduction in dependency on the preparation angle. The general reduction in stump height of the abutments was independent of the preparation angle. The double-mix technique showed decent increased abutments and is thus recommended for impressions of supragingival preparations.


Asunto(s)
Técnica de Impresión Dental , Modelos Dentales , Análisis de Varianza , Sulfato de Calcio , Pilares Dentales , Materiales de Impresión Dental/química , Humanos , Imagenología Tridimensional , Ensayo de Materiales , Polivinilos/química , Presión , Resinas Sintéticas/química , Siloxanos/química , Acero Inoxidable , Propiedades de Superficie , Factores de Tiempo
13.
J Oral Rehabil ; 34(1): 34-40, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17207076

RESUMEN

The purpose of this study was to investigate the distractive effect of posterior occlusal pivots on the temporomandibular joint. The study comprised 23 healthy subjects. None of them had a third molar and none of them had a missing tooth or showed tooth mobility. All subjects clenched (i) on 1 mm tin foil positioned between the teeth 17/47 and 27/37; (ii) on a stiff bite registration material of 1 mm thickness that prevented protrusion because of its bold occlusal relief. During clenching on the tin foil and on the protrusion preventing bite registration material, respectively, the vertical and horizontal condylar position was measured using a 6 d.f. ultrasonic motion analyser. Clenching with maximal force on the tin foil lead to a noticeable anterior downward directed movement of the condyle. Clenching on the protrusion preventing pivot, however, caused a statistically significant upward condylar movement of about 0.3 mm. These results indicate that occlusal pivots have no distractive effect on the temporomandibular joint but can lead to unwanted joint compression, if they are designed in a way that is preventing protrusion.


Asunto(s)
Cóndilo Mandibular/fisiología , Ferulas Oclusales , Articulación Temporomandibular/fisiología , Adulto , Fuerza de la Mordida , Femenino , Humanos , Registro de la Relación Maxilomandibular , Masculino , Persona de Mediana Edad
14.
Schmerz ; 19(1): 18-25, 2005 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-15712004

RESUMEN

OBJECTIVE: Can chronic pain of the masticatory muscles be positively affected by low dose injection of botulinum toxin (BTX-A)? METHODS: Twenty patients suffering chronic myofacial pain were questioned and examined after injection of 25-50 U Dysport into the affected muscles over a period of 8 weeks. RESULTS: Four weeks after injection of BTX-A patients reported a significant reduction of pain (p <0.001, paired t-test. Power of performed test with alpha 0.050:1.000). Then the pain remained constant over the next 4 weeks. Concurrently a significant increase of mandubular range of movement was observed (p <0,05, Wilcoxon signed rank test). CONCLUSIONS: Even though lacking placebo control the findings suggest that patients suffering chronic myofacial pain may benefit from injection of low dose BTX-A into the affected muscles.


Asunto(s)
Toxinas Botulínicas/uso terapéutico , Dolor Facial/tratamiento farmacológico , Músculos Masticadores/fisiopatología , Adulto , Dolor Facial/etiología , Femenino , Humanos , Masculino , Músculos Masticadores/efectos de los fármacos
15.
Laryngorhinootologie ; 81(4): 268-75, 2002 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-11973678

RESUMEN

INTRODUCTION: Since the thirties the hypothesis of a direct connection between temporomandibular disorders (TMD) and tinnitus/otalgia has been discussed. The thesis of this possible connection is often named after one of the earliest and most vehement supporters as "Costen Syndrome". This review is aimed to elucidate the present state of the discussion from the Dentist's point of view. DIAGNOSIS/EPIDEMIOLOGY/THERAPY OF TMD: Diagnostic research criteria which define TMD are not standardized. Despite high prevalence and strong demand for treatment of TMD there is still a lack of a commonly accepted standard therapy and the potential benefit from a therapeutic point of view is still controversial. TMD AND TINNITUS/OTALGIA:: Concurrence of TMD and tinnitus by a common underlying cause is still unproven. By contrast a causal link between certain forms of TMD and otalgia is obvious. CONCLUSION: A lack of clear definitions and standards for the diagnosis of TMD is the main hinderance to prove a causal relationship especially between TMD otalgia. However patients seeking care for otalgia with no identifiable otologic cause may benefit from dental therapy. Therefore future studies should focus on well defined subgroups of TMD to investigate a link between otalgia/tinnitus and TMD.


Asunto(s)
Atención Odontológica , Otolaringología , Síndrome de la Disfunción de Articulación Temporomandibular/diagnóstico , Diagnóstico Diferencial , Dolor de Oído/etiología , Humanos , Grupo de Atención al Paciente , Síndrome de la Disfunción de Articulación Temporomandibular/etiología , Síndrome de la Disfunción de Articulación Temporomandibular/terapia , Acúfeno/etiología
16.
J Reprod Fertil ; 117(1): 189-97, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10645260

RESUMEN

A dopaminergic system in the zona incerta stimulates LH release and may mediate the positive feedback effects of the gonadal steroids on LH release. In this study the mechanisms by which steroids might increase dopamine activity in the zona incerta were investigated. In addition, experiments were conducted to determine whether the inhibitory effects of gamma-aminobutyric acid (GABA) on LH release in the zona incerta are due to suppression of dopamine activity in this area or conversely whether the stimulatory effects of dopamine on LH release are due to suppression of a tonic inhibitory GABAergic system. Ovariectomized rats were treated s.c. with oil, 5 micrograms oestradiol benzoate or 5 micrograms oestradiol benzoate followed 48 h later by 0.5 mg progesterone, and killed 54 h after the oestradiol benzoate injection. At this time the LH concentrations were suppressed in the oestradiol benzoate group and increased in the group treated with oestradiol benzoate and progesterone. The ratio of tyrosine hydroxylase:beta-actin mRNA in the zona incerta was significantly increased by the oestradiol benzoate treatment, but the addition of progesterone resulted in values similar to those in the control group. At the same time, the progesterone treatment increased tyrosine hydroxylase activity in the zona incerta as indicated by an increase in L-dihydroxyphenylalanine (L-DOPA) accumulation after 100 mg 3-hydroxybenzylhydrazine hydrochloric acid (NSD1015) kg-1 and an increase in dopamine release as indicated by a increase in dihydroxyphenylacetic acid (DOPAC) concentrations (one of the major metabolites of dopamine). Ovariectomized rats treated with oestradiol benzoate plus progesterone were also injected i.p. with 75 mg gamma-acetylenic GABA kg-1 (a GABA transaminase inhibitor) to increase GABA concentrations in the brain. This treatment had no effect on the ratio of tyrosine hydroxylase:beta-actin mRNA but decreased L-DOPA accumulation and DOPAC concentrations in the zona incerta, indicating a post-translational inhibition of dopamine synthesis and release. Treatment of ovariectomized rats with oestradiol benzoate followed by 100 mg L-DOPA i.p. to increase dopamine concentrations in the whole brain had no effect on glutamic acid decarboxylase mRNA expression in the zona incerta, although it increased the glutamic acid decarboxylase:beta-actin mRNA ratio in other hypothalamic areas (that is, the medical preoptic area, ventromedial nucleus and arcuate nucleus). In conclusion, the steroids act to increase dopamine activity in different ways: oestrogen increases tyrosine hydroxylase mRNA expression and progesterone acts after translation to increase tyrosine hydroxylase activity and dopamine release (as indicated by increases in DOPAC concentrations). This latter effect may be due to progesterone removing a tonic GABAergic inhibition from the dopaminergic system.


Asunto(s)
Dopamina/metabolismo , Estradiol/farmacología , Hipotálamo/metabolismo , Hormona Luteinizante/metabolismo , Progesterona/farmacología , Ácido gamma-Aminobutírico/farmacología , Ácido 3,4-Dihidroxifenilacético/metabolismo , 4-Aminobutirato Transaminasa/antagonistas & inhibidores , Actinas/genética , Actinas/metabolismo , Alquinos , Aminocaproatos/farmacología , Análisis de Varianza , Animales , Encéfalo/metabolismo , Inhibidores Enzimáticos/farmacología , Femenino , Glutamato Descarboxilasa/genética , Glutamato Descarboxilasa/metabolismo , Hipotálamo/efectos de los fármacos , Hormona Luteinizante/sangre , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismo
17.
J Med Genet ; 35(4): 269-72, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9598717

RESUMEN

The microsomal glucose-6-phosphatase (G6Pase) complex regulates the final step in glucose production from glycogenolysis and gluconeogenesis. Glycogen storage disease type 1c (GSD-1c) results from deficient activity of the phosphate/ pyrophosphate transporter of this complex and is associated with neutropenia as well as hepatomegaly and hypoglycaemia. Using three affected subjects from a single highly consanguineous family, we have used homozygosity mapping to localise the gene responsible for GSD-1c to a 10.2 cM region on 11q23.3-24.2. The maximum lod score was 3.12. GSD-1c is therefore distinct from GSD-1a, which has been shown previously to be caused by mutations in the G6Pase gene on chromosome 17.


Asunto(s)
Cromosomas Humanos Par 11 , Enfermedad del Almacenamiento de Glucógeno Tipo I/genética , Adulto , Niño , Mapeo Cromosómico , Femenino , Glucosa-6-Fosfatasa/genética , Homocigoto , Humanos , Masculino , Mutación , Linaje
18.
Br J Obstet Gynaecol ; 105(6): 641-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9647155

RESUMEN

OBJECTIVE: To compare plasma catecholamine (noradrenaline and adrenaline) levels in pre-eclamptic to normotensive pregnancy, and to study the activity of synthetic enzymes for catecholamines in placental and trophoblastic cell cultures. We postulated that catecholamines might be an important signal secreted by the fetoplacental unit in pre-eclampsia. METHODS: We recruited 12 women with pre-eclampsia and 12 pregnant women with nonproteinuric hypertension undergoing delivery by caesarean section, 23 normotensive women undergoing elective caesarean section at term, and 26 normotensive primigravid women with ongoing pregnancies at gestations equivalent to those women with pre-eclampsia. We measured venous blood concentrations of catecholamines. Following delivery, we studied tyrosine hydroxylase (the rate limiting enzyme for catecholamine synthesis) activity in placental tissue of these women as well as from four eclamptic women not in the observer study. We used Northern blot analysis to quantify mRNA for tyrosine hydroxylase and dopamine-beta-hydroxylase (D-beta-H, a non-rate-limiting synthetic enzyme for catecholamine) in placental tissue, as well as in trophoblast cells in primary culture and trophoblast cell lines. RESULTS: Venous blood concentrations of noradrenaline were significantly higher in pre-eclamptic women compared with normotensive women. Tyrosine hydroxylase activity was greater in placental tissue from pre-eclamptic and eclamptic compared with normotensive pregnancies, as were mRNA levels for this enzyme. The mRNA levels for the non-rate-limiting D-beta-H in women with pre-eclampsia were similar to those in normotensive pregnancies. First trimester trophoblast cells in primary culture and trophoblast cell lines transcript mRNA for tyrosine hydroxylase and D-beta-H. CONCLUSIONS: Trophoblasts have the capacity to secrete catecholamines, and we found increased activity of the rate-limiting synthetic enzyme in placental tissue from pre-eclamptic pregnancies. We postulate that the higher levels of catecholamines we found in the plasma of women with pre-eclampsia might be of placental origin. We hypothesise that in pre-eclampsia ischaemic trophoblast tissue secretes catecholamines as a physiological signal to increase maternal blood flow to the fetoplacental unit, which itself is spared the vasoconstrictor effects of catecholamines (placental vessels are known to be unresponsive to catecholamines). However, since the basic pathology--defective trophoblast invasion--is not corrected, the increased blood flow fails to resolve the ischaemia, and the secretion of catecholamines is therefore sustained or even enhanced. Noradrenaline is known to cause lipolysis. This results in breakdown of triglycerides to free fatty acids, which are oxidized to lipid peroxides. The latter are cytotoxic and cause widespread endothelial cell damage and dysfunction, culminating in the clinical syndrome of pre-eclampsia.


Asunto(s)
Norepinefrina/sangre , Preeclampsia/sangre , Adulto , Northern Blotting , Células Cultivadas , Dopamina beta-Hidroxilasa/metabolismo , Epinefrina/sangre , Femenino , Sangre Fetal/metabolismo , Humanos , Placenta/enzimología , Preeclampsia/etiología , Preeclampsia/metabolismo , Embarazo , ARN Mensajero/metabolismo , Tirosina 3-Monooxigenasa/metabolismo
19.
Hum Genet ; 106(3): 351-4, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10798366

RESUMEN

Autosomal recessive Robinow syndrome is a form of mesomelic dwarfism with multiple rib and vertebral anomalies. Using autozygosity mapping we have identified a genetic locus (RBNW1) for this syndrome at chromosome 9q22 in seven consanguineous families from Oman. Our results indicate that the gene lies within a 4 cM region between markers D9S1836 and D9S1803 (maximum multipoint LOD score 12.3). In addition, we have analysed two non-Omani families with autosomal recessive Robinow and found no genetic heterogeneity.


Asunto(s)
Cromosomas Humanos Par 9/genética , Enanismo/genética , Huesos/anomalías , Brasil , Mapeo Cromosómico , Consanguinidad , Genes Recesivos , Ligamiento Genético , Haplotipos , Humanos , Escala de Lod , Repeticiones de Microsatélite , Omán , Reino Unido
20.
Appl Microbiol ; 17(1): 102-5, 1969 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-5774751

RESUMEN

An unidentified actinomycete, RTI 246, was found to produce antimycin A(1) in high yield on a high protein cereal medium. The antibiotic compound was extracted from the cells and isolated in pure form by crystallization. It was identified by ultraviolet, infrared, nuclear magnetic resonance, and mass spectroscopy and by alkaline hydrolysis to antimycic acid and a neutral lactone. The intravenous LD(50) was 1.0 mg/kg in white mice, whereas the intraperitoneal LD(50) was 1.50 +/- 0.19 mg/kg. Animals receiving an intraperitoneal injection displayed an incoordination of the hind limbs and impaired reflexes before showing signs of respiratory distress. These findings indicated that antimycin A(1) possesses a neurotoxic property separate from its well-documented property as a respiratory poison.


Asunto(s)
Antimicina A/aislamiento & purificación , Antimicina A/toxicidad , Actinomycetales/metabolismo , Animales , Antimicina A/administración & dosificación , Antimicina A/biosíntesis , Cristalización , Inyecciones Intraperitoneales , Inyecciones Intravenosas , Espectroscopía de Resonancia Magnética , Ratones , Análisis Espectral
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