RESUMEN
Holocarboxylase synthetase (HLCS) is an enzyme that catalyzes the incorporation of biotin into apo-carboxylases, and its deficiency causes biotin-responsive multiple carboxylase deficiency. The reported sequences of cDNA for human HLCS from liver, lymphocyte, and KG-1 myeloid cell lines differ at their 5' regions. To elucidate variations of the human HLCS mRNA and longer 5' cDNA ends, we performed screening of the human liver cDNA library and rapid amplification of the cDNA ends (RACE). Our results suggest the existence of three types of HLCS mRNA that start at different exons. The first type starts at exon 1, and the second type starts at exon 3, and both are found in various human tissues. The third type, corresponding to the cDNA from the KG-1 cell, starts at exon 2 of the HLCS gene. Various splicing patterns from exons 3-6 were also observed. None of the variations of cDNA found created a new initiation codon. Mutation screening from exons 6-14, therefore, was sufficient to detect amino acid changes in HLCS in patients. Our direct sequencing strategy for screening mutations in the HLCS gene revealed mutations in five Japanese patients and seven non-Japanese patients. Our analyses involving 12 Japanese and 13 non-Japanese patients and studies by others indicate that (1) there is no panethnically prevalent mutation; (2) the Arg508Trp, Gly581Ser, and Val550Met mutations are found in both Japanese and non-Japanese populations; (3) the IVS10+5G-->A mutation is predominant and probably a founder mutation in European patients; (4) the 655-656insA, Leu237Pro, and 780delG mutations are unique in Japanese patients; (5) the spectrum of the mutations in the HLCS gene may vary substantially among different ethnic groups.
Asunto(s)
Ligasas de Carbono-Nitrógeno/genética , Mutación , Secuencia de Bases , Ligasas de Carbono-Nitrógeno/deficiencia , Línea Celular Transformada , Cromosomas Humanos Par 21 , Cartilla de ADN , ADN Complementario , Etnicidad , Femenino , Humanos , Masculino , ARN Mensajero/genéticaRESUMEN
An in vitro organ culture system with developing mouse palates was improved to characterize the cleft palate (CP)-inducing potential of chemicals and underlying mechanisms. Palatal explants collected from gestation day 12 mouse fetuses were cultured with various concentrations of teratogens and examined for palatal development after 48 and 72 h of culture to assess effects of the chemicals on growth and/or fusion of palatal shelves. When the explants were exposed to diphenylhydantoin or 5-fluorouracil, palatal growth was inhibited in a concentration-dependent manner at 48 h. Suppression of the expression of proliferative cell nuclear antigen revealed poor cell proliferation. At 72 h, the incidence of explants with CP was significantly increased in the high-dose groups, suggesting that CP induction is mainly attributable to inhibition of palatal growth. By contrast, retinoic acid and hydrocortisone significantly lowered the rates of fused palates at 72 h in all treated groups, while they exhibited no effects on palatal growth at 48 h even at the highest concentration. Because no apoptosis was found in the epithelial cells at the tip of these palates, these chemicals are suggested to inhibit palatal fusion process by preventing apoptosis.
Asunto(s)
Fisura del Paladar/inducido químicamente , Desarrollo Embrionario y Fetal/efectos de los fármacos , Hueso Paladar/efectos de los fármacos , Teratógenos/toxicidad , Animales , División Celular , Fisura del Paladar/metabolismo , Fisura del Paladar/patología , Relación Dosis-Respuesta a Droga , Femenino , Fluorouracilo/toxicidad , Hidrocortisona/toxicidad , Masculino , Ratones , Ratones Endogámicos ICR , Técnicas de Cultivo de Órganos , Hueso Paladar/anomalías , Hueso Paladar/embriología , Fenitoína/toxicidad , Tretinoina/toxicidadRESUMEN
The human ABCG1 gene encodes a member of the ATP-binding cassette (ABC) superfamily of transporter proteins and is highly induced when macrophages are incubated with oxysterols. Using mRNA from oxysterol-treated human THP-1 cells together with 5'-rapid amplification of cDNA ends and polymerase chain reaction, we identified a novel ABCG1 transcript that encodes a putative protein of 786 residues containing a new amino terminus of 203 amino acids. Characterization of the genomic organization and structure of the human ABCG1 gene demonstrates that: (i) the gene consists of 23 exons spanning 98 kilobase pairs (kb) on chromosome 21q22.3, (ii) the 203 amino acids are encoded on three previously unidentified exons, 8-10, and (iii) a promoter, containing a TATA box and two liver X receptor (LXR) alpha response elements (LXREs), is located upstream of exon 8. Northern analysis using exon-specific probes confirms that oxysterol treatment results in >10-fold induction of ABCG1 transcripts that are derived from either exons 8-23 or exons 5, 7, and 11-23. Electromobility shift assays demonstrate that LXRalpha and retinoid X receptor alpha bind to the two LXREs in intron 7. Cells were transiently transfected with reporter luciferase constructs under the control of either (i) 9 kb of genomic DNA corresponding to intron 7 and part of exon 8 and containing either wild-type or mutant LXREs or (ii) two copies of the wild-type or mutant LXRE. In all cases, the wild-type construct was regulated in an LXR- and oxysterol-dependent manner, and this regulation was attenuated when the LXREs were mutated. In conclusion, the human ABCG1 gene contains multiple promoters, spans more than 98 kb and comprises 23 exons that give rise to alternative transcripts encoding proteins with different amino-terminal sequences. Elucidation of the various roles of different ABCG1 isoforms will be important for our understanding of mammalian cholesterol homeostasis.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Regiones Promotoras Genéticas , Receptores Citoplasmáticos y Nucleares , Receptores de Ácido Retinoico/metabolismo , Receptores de Hormona Tiroidea/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1 , Transportadoras de Casetes de Unión a ATP/biosíntesis , Transportadoras de Casetes de Unión a ATP/química , Algoritmos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Línea Celular , Colesterol/biosíntesis , Colesterol/química , Cromosomas Humanos Par 21 , ADN Complementario/metabolismo , Proteínas de Unión al ADN , Dimerización , Activación Enzimática , Exones , Regulación de la Expresión Génica , Genes Reporteros , Humanos , Receptores X del Hígado , Luciferasas/metabolismo , Macrófagos/metabolismo , Modelos Genéticos , Datos de Secuencia Molecular , Receptores Nucleares Huérfanos , Reacción en Cadena de la Polimerasa , Unión Proteica , Isoformas de Proteínas , Estructura Terciaria de Proteína , ARN Mensajero/metabolismo , Receptores de Esteroides/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , TransfecciónRESUMEN
The peroxisome targeting signal type 1 (PTS1) receptor, Pex5p, of the tetratricopeptide repeat (TPR) motif family is located mostly in the cytosol and mediates the translocation of PTS1 proteins to peroxisomes. As a step towards understanding the mechanisms of protein import into peroxisomes, we investigated the molecular mechanisms involved in PTS1 recognition by Pex5p with regard to requirement of energy and cytosolic factors, using cell-free synthesized acyl-CoA oxidase (AOx) as a PTS1 cargo protein, together with Pex5p and heat-shock protein (Hsp)70 from rat liver. Pex5p was partly associated with peroxisomes of rat liver, was resistant to washing with a high concentration of salt and to alkaline extraction and was inaccessible to protease added externally. Pex5p bound to AOx in an ATP-dependent manner. AOx synthesized in a cell-free translating system from rabbit reticulocyte lysate was imported into peroxisomes without being supplemented with Pex5p and Hsp70, implying that peroxisome-associated Pex5p was released from the membranes and functional in this in vitro import assay. Antibodies against Pex5p and Hsp70 inhibited AOx import. In contrast, AOx synthesized in a wheat-germ lysate required the external addition of Pex5p for import, in which Hsp70 augmented the AOx import. The TPR domain of Pex5p was revealed to bind to the N-terminal part in an Hsp70-independent manner, whereas mutual interaction of the TPR region was noted in the presence of Hsp70. Hsp70 interacted with the TPR domain of Pex5p. Moreover, Hsp70 and ATP synergistically enhanced the binding of Pex5p to the C-terminal PTS1-containing part of AOx, implying that Pex5p recognizes its cargo PTS1 protein by chaperone-assisted as well as energy-dependent mechanisms in vivo.
Asunto(s)
Proteínas HSP70 de Choque Térmico/metabolismo , Hígado/metabolismo , Peroxisomas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Anticuerpos/farmacología , Cricetinae , Cricetulus , Citosol/metabolismo , Proteínas HSP70 de Choque Térmico/antagonistas & inhibidores , Proteínas HSP70 de Choque Térmico/química , Cinética , Modelos Biológicos , Receptor de la Señal 1 de Direccionamiento al Peroxisoma , Transporte de Proteínas , Ratas , Receptores Citoplasmáticos y Nucleares/antagonistas & inhibidores , Receptores Citoplasmáticos y Nucleares/química , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
3-Methylcrotonyl-CoA carboxylase (MCCase; EC 6.4.1.4) is a mitochondrial biotin enzyme and plays an essential role in the catabolism of leucine and isovalerate in animals, bacterial species, and plants. MCCase consists of two subunits, those that are biotin-containing and non-biotin-containing. The genes responsible for these subunits have been isolated in soybean, Arabidopsis thaliana, and tomatoes, but not in mammals. In humans, MCCase deficiency has been thought to be a rare metabolic disease, but the number of patients with MCCase deficiency appears to be increasing with a wide range of clinical presentations, some that result in a lethal condition and others that are asymptomatic. In this report, we have isolated and carried out chromosomal mapping of the gene for the biotin-containing subunit (A subunit) of the human MCCase gene, MCCA. The cDNA predicts an open reading frame coding for a 725-amino-acid protein with mitochondrial signal peptide, biotin carboxylase, and biotin-carrier domains. The gene is composed of at least 19 exons and covers more than 70 kb of sequence on band q27 of chromosome 3. MCCA was abundantly expressed in mitochondria-rich organs, such as the heart, skeletal muscles, kidney, and liver. In exon 13, we observed a His/Pro polymorphism at codon 464 (an A to C transition at nucleotide position 1391 in the cDNA sequence). Then, we determined the DNA sequences of the 5' untranslated region and entire coding regions in two patients with MCCase deficiency, but no sequence substitution was detected, suggesting that the gene mutations might be in the non-biotin-containing subunit (B subunit) gene, MCCB, in these patients.
Asunto(s)
Biotina , Ligasas de Carbono-Carbono/genética , Cromosomas Humanos Par 3 , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Ligasas de Carbono-Carbono/química , Ligasas de Carbono-Carbono/deficiencia , Bandeo Cromosómico , Mapeo Cromosómico , Análisis Mutacional de ADN , ADN Complementario , Exones , Femenino , Expresión Génica , Genotipo , Humanos , Japón , Masculino , Datos de Secuencia Molecular , Linaje , Polimorfismo GenéticoRESUMEN
cDNA encoding Schizosaccharomyces pombe alpha-glucosidase was cloned from a library constructed from mRNA of the fission yeast, and expressed in Saccharomyces cerevisiae. The cDNA, 4176 bp in length, included a single ORF composed of 2910 bp encoding a polypeptide of 969 amino-acid residues with M(r) 106 138. The deduced amino-acid sequence showed a high homology to those of alpha-glucosidases from molds, plants and mammals. Therefore, the enzyme was categorized into the alpha-glucosidase family II. By site-directed mutagenesis, Asp481, Glu484 and Asp647 residues were confirmed to be essential in the catalytic reaction. The carboxyl group (-COOH) of the Asp647 residue was for the first time shown to be the most likely proton donor acting as the acid catalyst in the alpha-glucosidase of family II. Studies with the chemical modifier conduritol B epoxide suggested that the carboxylate group (-COO-) of the Asp481 residue was the catalytic nucleophile, although the role of the Glu484 residue remains obscure.
Asunto(s)
Ácido Aspártico/química , Schizosaccharomyces/química , alfa-Glucosidasas/química , Secuencia de Aminoácidos , Secuencia de Bases , Catálisis , Dicroismo Circular , Clonación Molecular , ADN Complementario/metabolismo , Electroforesis en Gel de Poliacrilamida , Biblioteca de Genes , Ácido Glutámico/química , Concentración de Iones de Hidrógeno , Cinética , Modelos Químicos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Sistemas de Lectura Abierta , Plásmidos/metabolismo , Protones , ARN Mensajero/metabolismo , Proteínas Recombinantes/metabolismo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Temperatura , Factores de Tiempo , alfa-Glucosidasas/metabolismoRESUMEN
Six new minor saponins, together with known ginsenosides, were isolated from the leaves of Panax ginseng. The new saponins were named as ginsenoside-Rh5, -Rh6, -Rh7 -Rh8, -Rh9 and -Rg7, and their structures were elucidated on the basis of chemical and physicochemical evidence to be as follows: ginsenoside-Rh5: 3beta,6alpha,12beta,24zeta-tetrahydroxy-dammar-20(22),25-diene 6-O-beta-D-glucopyranoside (1), -Rh6: 3beta,6alpha12beta,20(S)-tetrahydroxy-25-hydroperoxy-dammar-23-ene 20-O-beta-D-glucopyranoside (2), -Rh7: 3beta,7beta,12beta,20(S)-tetrahydroxy-dammar-5,24-diene 20-O-beta-D-glucopyranoside (3), -Rh8: 3beta,6alpha,20(S)-trihydroxy-dammar-24-ene-12-one 20-O-beta-D-glucopyranoside (4), -Rh9: 3beta,6alpha,20(S)-trihydroxy-12beta,23-epoxy-dammar-24-ene 20-O-beta-D-glucopyranoside (5) and -Rg7: 3-O-beta-D-glucopyranosyl 3beta,12beta,20(S),24(R)-tetrahydroxy-dammar-25-ene 20-O-beta-D-glucopyranoside (6).
Asunto(s)
Panax/química , Plantas Medicinales , Saponinas/química , Esteroides/química , Triterpenos/química , Fenómenos Químicos , Química Física , Hidrólisis , Espectroscopía de Resonancia Magnética , Extractos Vegetales/análisis , Hojas de la Planta/química , Saponinas/aislamiento & purificación , Espectrometría de Masa Bombardeada por Átomos Veloces , Esteroides/aislamiento & purificación , Triterpenos/aislamiento & purificación , DamaranosRESUMEN
Peripheral blood progenitor cells are collected effectively by leukapheresis of a large volume of peripheral blood. However, protection must be taken for patients or donors from hypocalcemia due to continuous infusion of citric acid. We found a tendency for hypocalcemic symptoms in patients or donors to occur more often on the second day than the first day of the sequential 2 days of leukapheresis. The doses of calcium gluconate supplement and the acid citrate dextrose-A solution administration significantly increased on the second day compared to that of the first day. The blood levels of c-terminal parathormone (PTH), phosphorus, and alkaline phosphatase did not show remarkably abnormal change. However, urine calcium excretion just after leukapheresis was higher than in the period before or after leukapheresis compared to the phosphorus or creatinine excretion. These findings indicate that the cause of a higher tendency to hypocalcemic symptoms on the second day of the sequential 2 days of leukapheresis is due to the higher metabolism of calcium being excreted in the urine during leukapheresis.
Asunto(s)
Calcio/metabolismo , Leucaféresis , Adulto , Donantes de Sangre , Calcio/sangre , Gluconato de Calcio/administración & dosificación , Ácido Cítrico/administración & dosificación , Ácido Cítrico/efectos adversos , Femenino , Humanos , Hipocalcemia/etiología , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
A human cDNA encoding a novel protein tyrosine phosphatase has been isolated. The phosphatase has unique features in its domain structure: a "Zn-hand" domain containing several SH3-binding motifs, a tyrosine phosphatase domain, a C-terminal PEST motif, and an N-terminal domain similar to yeast BRO1, an apoptosis-related mammalian AIP1 and to a RHO-binding protein, Rhophilin. The gene is located at chromosome 3p21.3, an area frequently deleted in many types of cancer, especially within the functionally defined narrow region. The gene may be a human homolog of the rat PTP-TD14 gene reported by others, which can suppress H-ras-mediated transformation. We identified a hemizygous missense mutation in a lung cancer cell line. Thus, the phosphatase gene may be a candidate for one of the tumor suppressor genes located on 3p21.3.
Asunto(s)
Cromosomas Humanos Par 3 , Pérdida de Heterocigocidad , Proteínas Tirosina Fosfatasas/genética , Secuencia de Aminoácidos , Animales , Mapeo Cromosómico , Cromosomas Artificiales de Levadura , ADN Complementario , Marcadores Genéticos , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Estructura Secundaria de Proteína , Proteínas Tirosina Fosfatasas/química , Proteínas Tirosina Fosfatasas no Receptoras , Ratas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transfección , Células Tumorales CultivadasRESUMEN
Ankhzn (ankyrin repeats hooked to a zinc finger motif) was originally isolated by means of the gene trap method, as a novel cytoplasmic protein on mouse embryonic stem cells. The Ankhzn protein is ubiquitously expressed in a spatiotemporal-specific manner and is located on endosomes. In the present study, we have cloned human ANKHZN cDNA by PCR using candidate EST clones exhibiting a high homology to mouse Ankhzn cDNA. The human ANKHZN cDNA encoded a 1166aa protein exhibiting 84.9% identity to the mouse one. The size of the transcript was found to be about 7kb on a Northern blot analysis, and ANKHZN mRNA was found to be ubiquitously expressed in human tissues on RT-PCR analysis. Western blot analysis showed that a 130kDa protein was detected at various levels in human tissues and also present in both membrane and soluble fractions obtained on subcellular fractionation. Human ANKHZN is a single copy gene consisting of predicted 25 exons in the human genome, and has been mapped to human chromosome 17p13 by radiation hybrid panel and fluorescence in-situ hybridization.
Asunto(s)
Proteínas Portadoras/genética , Cromosomas Humanos Par 17/genética , Secuencia de Aminoácidos , Animales , Repetición de Anquirina , Northern Blotting , Southern Blotting , Western Blotting , Proteínas Portadoras/metabolismo , Mapeo Cromosómico , Clonación Molecular , ADN/genética , ADN Complementario/química , ADN Complementario/genética , Femenino , Expresión Génica , Humanos , Células Híbridas , Hibridación Fluorescente in Situ , Masculino , Proteínas de la Membrana , Ratones , Datos de Secuencia Molecular , Proteínas de Unión a Fosfato , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Distribución Tisular , Dedos de ZincRESUMEN
A stereocontrolled synthesis of the model compound for an anti-ulcer active polysaccharide (Bupleuran 2IIc) is described. Glycosidation of the disaccharide acceptor, 2-O-acetyl-3-O-benzyl-4-O-(p-methoxybenzyl)-alpha-L-rhamnopyranosyl-(1-- >4)-2,3,6-tri-O-benzyl-alpha-D-galactopyranosyl trichloroacetimidate, with the disaccharide receptor, allyl 3,4-di-O-benzyl-alpha-L-rhamnopyranosyl-(1-->4)-2,3,6-tri-O-benzyl-beta- D-galactopyranoside, using silver triflate (AgOTf) as a promoter gave the desired tetrasaccharide derivative, which was transformed into the acidic tetrasaccharide, corresponding to a segment of the rhamnogalacturonan (Bupleuran 2IIc) polysaccharide, propyl alpha-L-Rha-(1-->4)-alpha-D-GalA-(1-->2)-alpha-L-Rha-(1-->4)-beta-D-GalA , via removal of the corresponding ether and ester protecting groups, followed by oxidation.
Asunto(s)
Antiulcerosos/síntesis química , Pectinas/síntesis química , Antiulcerosos/química , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Modelos Químicos , Datos de Secuencia Molecular , Pectinas/químicaRESUMEN
Recent studies point to a key role for the estrogen synthesizing enzyme P450 aromatase (P450 arom) in ovary determination in fish, birds and reptiles. It is unclear whether estrogen synthesis is important in sex determination of Xenopus gonad. To determine whether the aromatase gene is transcribed in the gonads of Xenopus tadpoles during the sex determination, we cloned a P450 arom cDNA and examined the level of P450 arom and estrogen receptor (ER) gene expression in association with estrogen activity. cDNA clones for P450 arom were isolated from a Xenopus ovarian cDNA library. There was an open reading frame (ORF) of 1500 bp from the ATG start to TAA stop codons encoding 500 predicted amino acids. cDNAs for P450 arom have previously been cloned from various vertebrates. The homology between the Xenopus P450 aromatase and the human P450 arom was higher. The expression of the P450 arom gene was mainly limited to reproductive organs. To determine the beginning of estrogen activity in gonads of embryos, expression of the aromatase and ER gene was also examined by RQ-RT-PCR. Both Xenopus aromatase and ER mRNA was detected at stage 51 in gonads. These observations are consistent with estrogens having a key role in ovarian development in various other vertebrates.
Asunto(s)
Aromatasa/genética , Larva/fisiología , Ovario/metabolismo , Receptores de Estrógenos/genética , Secuencia de Aminoácidos , Animales , Aromatasa/química , Aromatasa/metabolismo , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , Femenino , Biblioteca de Genes , Humanos , Larva/crecimiento & desarrollo , Masculino , Datos de Secuencia Molecular , Ovario/enzimología , Ovario/crecimiento & desarrollo , ARN/metabolismo , Receptores de Estrógenos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Xenopus laevisRESUMEN
Wilson's disease is an autosomal recessive disorder related to the copper metabolism. The clinical symptoms are due to copper deposition in various tissues, including liver, brain, kidney, cornea and others. The key strategy of treatment is to reduce the amount of copper in the liver and other tissues by administering both copper-chelating agents and a low copper diet. D-Penicillamine is considered to be the first choice as a copper-chelating agent. Patients require 15-25 mg/kg daily in the early stages of treatment and this drug should also be given more than 2 h before meals. Some undesirable or serious side-effects, such as systemic lupus erythematosus (SLE) and nephrotic syndrome, do occur in 20-25% of all patients. In such cases, trienthylene tetramine (trientine) appears to be as effective as penicillamine. This drug is usually used when D-penicillamine has to be withdrawn. It is also sometimes administered to patients with neurological symptoms as a first-choice drug. It is given in doses of 40-50 mg/kg daily, in the same manner as for D-penicillamine. Zinc salt administration has also emerged as an interesting supportive therapy for both treatments. A dose of 5-7.5 mg/kg daily is given before meals. The copper content of the diet should be less than 1 mg/day in the early stages of treatment. Thereafter, it can be increased to 1.0-1.5 mg/day during well-controlled periods. Liver transplantation is now performed in many countries for patients with either the fulminant or chronic progressive types of Wilson's disease.
Asunto(s)
Quelantes/uso terapéutico , Terapia por Quelación , Cobre , Degeneración Hepatolenticular/terapia , Penicilamina/uso terapéutico , Degeneración Hepatolenticular/metabolismo , Degeneración Hepatolenticular/cirugía , Humanos , Hígado/metabolismo , Trasplante de Hígado , Resultado del TratamientoRESUMEN
Based on the clinical course of a 16-year-old boy with type I Crigler-Najjar syndrome, we estimated the threshold concentration of unbound bilirubin, as assayed by the horseradish peroxidase method, that apparently induces toxicity to the brain. Before the age of 15, the patient did not manifest any neurological or behavioural dysfunction despite increased bilirubin in serum. The binding affinity and the binding capacity of the patient's serum albumin for bilirubin determined when he was about 14 years old were 10(8)(mol/L)-1 and 1.01 to 1.04 mol/L, respectively. These values were nearly the same as those of normal controls reported in the literature. The total bilirubin binding capacity was greater than the patient's total bilirubin concentration, showing that his serum albumin was not saturated with bilirubin. The reserve bilirubin binding capacity (RBBC) was estimated to be 158 mumol/L and the unbound bilirubin concentration to be 15.1 nmol/L. Concentration of unbound bilirubin peaked at 21.7 nmol/L at the age of 15 years and 11 months, i.e. 2 months before the onset of difficulties in walking and speaking. At this time, the RBBC was estimated as -64 mumol/L. A peak concentration of total bilirubin, 811 mumol/L, was observed during the period of rapid loss of the ability to walk or speak. At the age of 16 years and 1 month the RBBC decreased to -98 mumol/L and the unbound bilirubin concentration to 18.8 nmol/L. Following phototherapy, the patient's neurological state returned to normal; he could speak and walk normally. At the age of 16 years and 2 months the RBBC returned to 105 mumol/L and unbound bilirubin decreased to 16.6 nmol/L. These results suggest that maintaining the concentration of unbound bilirubin at < 20 nmol/L and the total bilirubin concentration at lower than the binding capacity of serum albumin is important for prevention of neurological deficits in Crigler-Najjar syndrome. The upper limit of unbound bilirubin in such an older patient was nearly the same as that reported for newborns.
Asunto(s)
Bilirrubina/sangre , Síndrome de Crigler-Najjar/sangre , Enfermedades del Sistema Nervioso/complicaciones , Adolescente , Niño , Preescolar , Síndrome de Crigler-Najjar/complicaciones , Síndrome de Crigler-Najjar/fisiopatología , Humanos , MasculinoRESUMEN
Pharmacokinetic modulating chemotherapy (PMC) using oral UFT and continuous venous 5-FU infusion was administered to 22 resectable patients with Dukes' B2-D colorectal carcinomas. The regimen was arranged as follows: Group A (n = 12) UFT 300-450 mg/day, 5 days a week and 5-FU 440-600 mg/m2/24 hr (750-1,000 mg/body/24 hr) once a week, Group B (n = 10), UFT less than 300 mg/day, 5 days a week, and/ or 5-FU less than 440 mg/m2/24 hr (750 mg/body/ 24 hr) once a week. The control group (Group C, n = 26) was selected at random from among non-PMC cases matched for other background factors and in which surgery had been performed during the past 4 years. Fifteen out of 26 patients in Group C were treated with 5-FU masked compounds orally. The cumulative 2 year recurrent rates of Groups A, B and C were 8.3%, 52.0% and 50.0%, respectively; the rate of Group A was significantly lower than that of Group B (p < 0.05). Four patients who suffered from PMC-related side effects of grade 1-2 wanted to decrease their dosage of UFT and/or 5-FU. They were registered in Group B. These results suggest that the regimen of Group A was advantageous in improving the prognosis after resection of Dukes' B2-D colorectal carcinoma.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Neoplasias Colorrectales/cirugía , Terapia Combinada , Esquema de Medicación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Pronóstico , Distribución Aleatoria , Tegafur/administración & dosificación , Uracilo/administración & dosificaciónRESUMEN
We have isolated cDNA clones for a novel human protein, TRPC7 (transient receptor potential-related channels), which consists of 1503 amino acid residues from the fetal brain and caudate nucleus cDNA libraries. Northern blot analysis indicated that the TRPC7 gene is highly expressed as a 6.5-kb transcript in brain. The TRPC7 protein has significant homology with Caenorhabditis elegans hypothetical proteins T01H8.5, C05C12.3, and F54D1.5 and with Drosophila and human transient receptor potential (trp) proteins. The TRPC7 protein has seven putative transmembrane domains that probably constitute a Ca2+ channel as in the above-mentioned proteins. Genomic sequencing revealed that the TRPC7 gene consists of 32 exons spanning approximately 90 kb. The TRPC7 gene was mapped between D21S400 and D21S171 on human chromosome 21q22.3, 14 kb distal to a NotI site in D21S400. This novel TRPC7 gene could be a candidate gene for genetic disorders such as bipolar affective disorder, nonsyndromic hereditary deafness, Knobloch syndrome, and holoprosencephaly, which were mapped to this region.
Asunto(s)
Encéfalo/metabolismo , Canales de Calcio/genética , Clonación Molecular , Canales Iónicos , Proteínas de la Membrana , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Encéfalo/embriología , Canales de Calcio/química , Canales de Calcio/metabolismo , Mapeo Cromosómico , Cromosomas Humanos Par 21/genética , ADN Complementario , Exones , Humanos , Intrones , Datos de Secuencia Molecular , Especificidad de Órganos , Filogenia , Alineación de Secuencia , Canales Catiónicos TRPC , Canales Catiónicos TRPMRESUMEN
Recent studies have revealed that the brain produces interferon-alpha (IFN-alpha) in response to noninflammatory as well as inflammatory stress and that it might have a role in normal physiology. When administered intracerebrally, IFN-alpha causes diverse effects including fever, anorexia, analgesia and changes in the central neuronal activities. These responses are inhibited by the opioid receptor antagonist naloxone. This is consistent with the reports suggesting that recombinant human (rh) IFN-alpha binds to opioid receptors in rodent brain membrane. We revealed that rhIFN-alpha altered the activity of thermosensitive neurons in the medial preoptic area (MPO) and glucose-responsive neurons in the ventromedial hypothalamus in an opioid-receptor-dependent way. As a stress which produces opioid-dependent analgesia is known to suppress the cytotoxicity of splenic natural killer cells, we investigated whether the administration of beta-endorphin and rhIFN-alpha may induce a similar immunosuppression. We found that central, but not peripheral, injection of both compounds inhibited natural killer (NK) cytotoxicity. Further studies revealed that rhIFN-alpha decreased the activity of MPO neurons via opioid receptors and the altered activity of MPO neurons in turn resulted in the activation of corticotropin-releasing factor neurons, thereby suppressing NK cytotoxicity predominantly through activation of the splenic sympathetic nerve and beta-receptor mechanisms in splenocytes. Thus, IFN-alpha may alter the brain activity to exert a feedback effect on the immune system. Further detailed whole-cell clamping analyses on neuronal mechanisms in rat brain tissue slices showed that the inhibitory effect of rhIFN-alpha on N-methyl-D-aspartate-induced membrane current responses of MPO neurons was mediated not only by opioid receptors but also by the local production of reactive oxygen intermediates, nitric oxide and prostanoids, possibly due to neuron-glial cell interaction.
Asunto(s)
Hipotálamo/inmunología , Interferón-alfa/inmunología , Neuroinmunomodulación/inmunología , Animales , HumanosRESUMEN
We report a series a three psychophysical experiments designed to differentiate the contributions of the neocerebellar and prefrontal cortex to time perception. Comparison of patients with focal, unilateral neocerebellar or prefrontal lesions on temporal discrimination of 400-ms and 4-s intervals (Expt. 1) indicated that neocerebellar damage impaired timing in both millisecond and seconds ranges, whereas prefrontal damage resulted in deficits that were robust only at the longer duration. Patients with prefrontal lesions, however, also exhibited working memory deficits on a non-temporal task (Expt. 2), biases in point of subjective equality indicative of attentional deficits, and were disproportionately sensitive to strategic manipulations in a long-duration discrimination task (Expt. 3). In contrast, the pervasive timing deficits of cerebellar patients were relatively insensitive to strategic support and could not be readily explained by general deficits in working memory or attention. These findings support the hypothesis that neocerebellar regions subserve a central timing mechanism, whereas the prefrontal cortex subserves supportive functions associated with the acquisition, maintenance, monitoring and organization of temporal representations in working memory. Such functions serve to bridge the output of the central timing mechanism with behavior. Together, these regions appear to participate in a working memory system involved in discrimination of durations extending from a few milliseconds to many seconds.
Asunto(s)
Corteza Cerebelosa/fisiología , Corteza Prefrontal/fisiología , Percepción del Tiempo/fisiología , Estimulación Acústica , Anciano , Anciano de 80 o más Años , Mapeo Encefálico , Trastornos Cerebrovasculares/fisiopatología , Femenino , Humanos , Pruebas de Inteligencia , Masculino , Persona de Mediana Edad , Percepción de la Altura Tonal/fisiologíaRESUMEN
BACKGROUND: Video-assisted thoracic operations usually require single-lung ventilation under general anesthesia. However, for high-risk patients with other underlying pulmonary diseases, one has to consider risks of general anesthesia itself. METHODS: Four high-risk patients (4 men; mean age, 73 years) with intractable secondary pneumothorax and other underlying pulmonary diseases were treated by video-assisted thoracic operations under local and epidural anesthesia. Absorbable polyglycolic acid sheets and fibrin glue were used to control the air leakage. RESULTS: The mean duration of the procedure was 108 minutes. Pain and cough reflex were well controlled, and spontaneous breathing and hemodynamics were well maintained during the operation. The mean duration of the postoperative chest drainage was 5 days. No significant postoperative complication was encountered. No pneumothorax had recurred at a mean follow-up of 16 months. CONCLUSIONS: Video-assisted thoracic operations can be performed safely under local and epidural anesthesia for the treatment of intractable secondary pneumothorax in high-risk patients. The air leakage can be controlled with the use of polyglycolic acid sheets and fibrin glue without bullectomy.
Asunto(s)
Anestesia Epidural , Anestesia Local , Endoscopía , Neumotórax/cirugía , Toracoscopía , Anciano , Anestesia General , Tubos Torácicos , Contraindicaciones , Tos/fisiopatología , Tos/prevención & control , Adhesivo de Tejido de Fibrina/uso terapéutico , Estudios de Seguimiento , Hemodinámica/fisiología , Humanos , Cuidados Intraoperatorios , Enfermedades Pulmonares/complicaciones , Enfermedades Pulmonares/fisiopatología , Masculino , Dolor/fisiopatología , Dolor/prevención & control , Ácido Poliglicólico/química , Intercambio Gaseoso Pulmonar/fisiología , Recurrencia , Respiración Artificial/métodos , Factores de Riesgo , Mallas Quirúrgicas , Factores de Tiempo , Adhesivos Tisulares/uso terapéutico , Grabación en VideoRESUMEN
The root of Panax ginseng C.A. Meyer, is a well-known important Chinese traditional medicine used as a stomachic, tonic, sedative and as an elixir called Ginseng in China and Japan. The precise mechanism of the biological actions of this plant is not fully understood. In order to elucidate the immunomodulating activities of this plant, we examined the direct effects of four of its components, acidic polysaccharides isolated in previous studies, on cytokine (interleukin-8; IL-8) production by a human monocytic cell line, THP-1, and human blood monocytes in vitro, as IL-8 is a potent inflammatory cytokine involved in neutrophil chemotaxis and activation. We found that one component, ginsenan S-IIA, is a potent inducer of IL-8 production by human monocytes and THP-1 cells, and this induction is accompanied by increased IL-8 mRNA expression.