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1.
Mol Cell Biol ; 3(12): 2232-40, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6656765

RESUMEN

The hormonal requirements for the regulation of the major urinary protein (MUP) mRNA levels in mouse liver have been examined. Previous experiments have shown that administration of testosterone to female or castrated male mice increases MUP mRNA levels approximately fivefold to normal male levels. We have found that thyroxine and the peptide hormone, growth hormone, each had a pronounced effect on MUP mRNA levels. MUP mRNA was reduced 150-fold in growth-hormone-deficient mutant mice (little). The administration of growth hormone and thyroxine induced MUP mRNA approximately 150-fold, and when administered together, they induced MUP mRNA approximately 1,000-fold. testosterone administration. When administered separately to these mice, growth hormone and thyroxine induced with MUP mRNA approximately 150-fold, and when administered together, they induced MUP mRNA approximately 1,000-fold. Testicular feminized mice, which lack a functional major testosterone receptor protein, can also be induced to male levels by treatment with both growth hormone and thyroxine. In addition, we present evidence which indicates that growth hormone, thyroxine, and testosterone differentially regulate the levels of distinct MUP mRNA species.


Asunto(s)
Genes/efectos de los fármacos , Hormona del Crecimiento/farmacología , Hígado/metabolismo , Proteínas/genética , ARN Mensajero/genética , Testosterona/farmacología , Tiroxina/farmacología , Transcripción Genética/efectos de los fármacos , Animales , Electroforesis en Gel de Poliacrilamida , Hipofisectomía , Ratones , Ratones Endogámicos C57BL , Hibridación de Ácido Nucleico , Biosíntesis de Proteínas/efectos de los fármacos , Proteínas/aislamiento & purificación
2.
Mol Cell Biol ; 7(10): 3705-12, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2824995

RESUMEN

Mouse Ltk- cells were stably transfected with cloned genes encoding the mouse major urinary proteins (MUPs). C57BL/6J MUP genomic clones encoding MUP 2 (BL6-25 and BL6-51), MUP 3 (BL6-11 and BL6-3), and MUP 4 (BL6-42) have been identified. In C57BL/6J mice, MUP 2 and MUP 4 are known to be synthesized in male, but not female, liver, and MUP 3 is known to be synthesized in both male and female liver and mammary gland. A BALB/c genomic clone (BJ-31) was shown to encode a MUP that is slightly more basic than MUP 2 and was previously shown to be synthesized in both male and female liver of BALB/c but not C57BL/6 mice. Comigration on two-dimensional polyacrylamide gels of the MUPs encoded by the transfecting gene provides a basis for tentative identification of the tissue specificity and mode of regulation of each gene. DNA sequence analysis of the 5' flanking region indicates that the different MUP genes are highly homologous (0.20 to 2.40% divergence) within the 879 base pairs analyzed. The most prominent differences in sequence occur within an A-rich region just 5' of the TATA box. This region (from -47 to -93) contains primarily A or C(A)N nucleotides and varies from 15 to 46 nucleotides in length in the different clones.


Asunto(s)
Genes , Ratones Endogámicos/genética , Proteínas/genética , Animales , Secuencia de Bases , Clonación Molecular , Enzimas de Restricción del ADN , Regulación de la Expresión Génica , Células L , Ratones , Datos de Secuencia Molecular , Transfección
3.
IEEE Int Conf Rehabil Robot ; 2017: 702-707, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28813902

RESUMEN

This paper presents a real time hybrid 2D position and orientation tracking system developed for an upper limb rehabilitation robot. Designed to work on a table-top, the robot is to enable home-based upper-limb rehabilitative exercise for stroke patients. Estimates of the robot's position are computed by fusing data from two tracking systems, each utilizing a different sensor type: laser optical sensors and a webcam. Two laser optical sensors are mounted on the underside of the robot and track the relative motion of the robot with respect to the surface on which it is placed. The webcam is positioned directly above the workspace, mounted on a fixed stand, and tracks the robot's position with respect to a fixed coordinate system. The optical sensors sample the position data at a higher frequency than the webcam, and a position and orientation fusion scheme is proposed to fuse the data from the two tracking systems. The proposed fusion scheme is validated through an experimental set-up whereby the rehabilitation robot is moved by a humanoid robotic arm replicating previously recorded movements of a stroke patient. The results prove that the presented hybrid position tracking system can track the position and orientation with greater accuracy than the webcam or optical sensors alone. The results also confirm that the developed system is capable of tracking recovery trends during rehabilitation therapy.


Asunto(s)
Terapia por Ejercicio , Robótica/instrumentación , Rehabilitación de Accidente Cerebrovascular , Anciano de 80 o más Años , Algoritmos , Diseño de Equipo , Terapia por Ejercicio/instrumentación , Terapia por Ejercicio/métodos , Femenino , Humanos , Internet , Rehabilitación de Accidente Cerebrovascular/instrumentación , Rehabilitación de Accidente Cerebrovascular/métodos
4.
Cancer Res ; 54(24): 6496-9, 1994 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-7987848

RESUMEN

s.c. and abdominal tumors from interspecific hybrid, transgenic mice containing the SV40 early region linked to a renin enhancer/promoter were analyzed for loss of heterozygosity to identify chromosomal regions involved in tumorigenesis. A very high frequency of loss of heterozygosity/partial loss of heterozygosity or allelic imbalance involving the distal regions of chromosome 8 was observed in the s.c. tumors (76%) with frequent amplification (3-6 times) of the corresponding proximal regions including Junb, suggesting that chromosome 8 breakage and amplification promotes tumorigenesis in these mice.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Deleción Cromosómica , Renina/genética , Animales , Femenino , Ratones , Ratones Transgénicos
5.
Ann Thorac Surg ; 51(1): 136-7, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1985556

RESUMEN

We present a technique of myocardial protection using retrograde cold blood cardioplegia. This safe and simple method allows excellent continuous and homogeneous cooling of the heart during the ischemic period in all types of open heart operations.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Paro Cardíaco Inducido/métodos , Humanos
6.
J Cardiovasc Surg (Torino) ; 30(6): 877-81, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2600115

RESUMEN

Symptomatic carotid atherosclerotic disease occurring as a result of cervical irradiation often requires surgical intervention. Airway obstruction is an uncommon problem after most carotid surgery and has not been described for patients with cervical irradiation. Airway obstruction developed after two of five carotid endarterectomy procedures in previously irradiated necks requiring emergency tracheostomy or reintubation. Mechanisms of obstruction included endotracheal tube trauma to the fixed irradiated vocal cords and laryngeal edema caused by surgical dissection in an irradiated field. In addition, one patient in our series demonstrated hypercarbia as a result of bilateral carotid body ablation, a process known to impair the ventilatory response to hypoxia. An increased risk of airway obstruction after carotid surgery exists in patients with prior cervical irradiation. Preventive methods include the use of perioperative steroids and either carotid surgery with local anesthesia or bronchoscopic vocal cord visualization and intubation.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Arterias Carótidas/cirugía , Endarterectomía , Cuello/efectos de la radiación , Complicaciones Posoperatorias , Anciano , Arteriosclerosis/cirugía , Enfermedades de las Arterias Carótidas/cirugía , Femenino , Humanos , Intubación Intratraqueal , Masculino , Persona de Mediana Edad , Traumatismos por Radiación/complicaciones , Traumatismos por Radiación/cirugía , Factores de Riesgo , Traqueotomía
7.
J Forensic Sci ; 20(3): 484-500, 1975 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1151307

RESUMEN

A study has been made to demonstrate the capability of spark source mass spectrometry (SSMS) for differentiating bullets on the basis of elemental composition. Twenty-six elements are commonly found in bullet lead at the 0.1-ppm level and above. Only twelve of these prove to be generally useful for quantitative characterization. The precision of analysis with SSMS using photographic detection is about 10% relative standard deviation. The accuracy obtained in this study is considerably worse than this, about 30% average error. In spite of such large errors, SSMS is shown to be far superior to the more precise method of neutron activation analysis. The reason, of course, is the large number of elements determined by SSMS. Bullets do not have uniform elemental compositions within a box or lot. Instead, there are usually two or three distinct groups of bullets within a given box. Three Winchester boxes representing lots manufactured a few weeks apart showed common groups among them. All other boxes had unique groups of bullets, indicating that the method is a promising alternative to the conventional method of identifying bullets by physical markings.


Asunto(s)
Criminología , Espectrometría de Masas , Elementos Químicos/análisis , Medicina Legal , Análisis de Activación de Neutrones
8.
Acta Crystallogr C ; 56(Pt 4): E157-8, 2000 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15263191

RESUMEN

The title compound, C(13)H(15)N(3)O(7), crystallizes as two independent molecules which differ in their conformation. Intermolecular hydrogen bonding between the amide and carboxylic acid groups as N-H.O=C interactions results in the formation of one-dimensional chains with N.O distances of 2.967 (6) and 3.019 (6) A. Neighbouring chains are linked by C=O.H-O interactions to form a two-dimensional network, with O.O distances of 2.675 (6) and 2.778 (6) A.

11.
J Virol ; 3(2): 114-8, 1969 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-4304440

RESUMEN

Yaba tumor poxvirus deoxyribonucleic acid (DNA) has a density of 1.6905 in CsCl and its T(m) value in 0.015 m citrate in saline is 82.3. The guanine plus cytosine content estimated from these properties was taken to be 32.5 +/- 0.5%, a value 2 to 3% less than for DNA from other poxviruses reported to date.


Asunto(s)
ADN Viral/análisis , Virus del Tumor del Mono de Yaba/análisis , Animales , Centrifugación por Gradiente de Densidad , Fenómenos Químicos , Química Física , Citosina/análisis , ADN Viral/aislamiento & purificación , Densitometría , Electroforesis , Guanina/análisis , Haplorrinos , Métodos , Neoplasias Experimentales/microbiología , Virus del Tumor del Mono de Yaba/aislamiento & purificación
12.
Biochem Genet ; 23(3-4): 281-90, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2409959

RESUMEN

Rat alpha 2u-globulin and the mouse major urinary proteins (MUP) are encoded by homologous multigene families whose members exhibit diverse tissue-specific, developmental, and hormonal controls of expression. Although their patterns of expression and hormonal control appear to be very similar in many respects, we have found high levels of alpha 2u-globulin mRNA in rat preputial glands, whereas MUP mRNA could not be detected in the male mouse preputial gland. Male and female rat preputial have similar concentrations of alpha 2u-globulin mRNA, suggesting an absence of endocrine regulation as occurs in the liver and lachrymal glands. Two-dimensional polyacrylamide gel electrophoresis of proteins encoded by hybrid-selected alpha 2u-globulin mRNA indicates that the liver and lachrymal translation products have different mobilities. However, many of the preputial gland products comigrate with most or all of the liver and lachrymal products. Among the possibilities suggested by these results is that alpha 2u-globulin genes expressed in liver and lachrymal glands under endocrine control are also expressed constitutively in the preputial gland.


Asunto(s)
Genitales/fisiología , alfa-Globulinas/genética , Animales , Femenino , Regulación de la Expresión Génica , Aparato Lagrimal/fisiología , Hígado/fisiología , Masculino , Proteínas/genética , ARN Mensajero/genética , Ratas
13.
Acta Crystallogr C ; 56 Pt 11: 1407-10, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11077316

RESUMEN

The title compound, C(17)H(15)NO(4), derived from L-tyrosine, crystallizes with three independent molecules which differ in the conformation of the asymmetric unit: the N-C-C-C(ipso) torsion angles are -71.7 (5), -63.6 (6) and -52.5 (5) degrees, respectively. Deformations in the phenol ring hydroxy O-C-C angles of 116.5 (4)/123.9 (4), 121.7 (5)/118.1 (4) and 122.4 (5)/118.6 (5) degrees, respectively, result from their respective intermolecular hydrogen-bonding environments. Intermolecular O(acid)-H.O=C(indole), O(phenol)-H.O-H(phenol) and O(phenol)-H.O=C(indole) hydrogen bonds, with O.O distances in the range 2.607 (4)-2.809 (4) A, are present in combination with C-H.O and C-H.pi(arene) interactions. The primary hydrogen-bonding systems assemble with graph sets R(3)(3)(8) and R(3)(2)(22).

14.
J Biol Chem ; 252(23): 8489-97, 1977 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-925007

RESUMEN

Reovirus and globin mRNAs which lack a 5'-terminal 7-methylguanosine are translated in a fractionated cell-free protein-synthesizing system. Efficient translation occurs only at optimal concentrations of reticulocyte initiation factor preparations and does not occur at optimal concentrations of ascites initiation factor preparations or at suboptimal concentrations of reticulocyte initiation factor preparations. The translation of "uncapped" mRNA in vitro, therefore, appears to be related to the efficiency of initiation of protein synthesis. At optimal concentrations of reticulocyte initiation factors, mRNA containing a 5'-terminal 7-methylguanosine is preferentially translated in the presence of mRNA which lacks a "cap." These results indicate that the 5'-terminal 7-methylguanosine on mRNA has a facilitatory rather than obligatory role in translation.


Asunto(s)
Guanosina/análogos & derivados , Factores de Iniciación de Péptidos , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Animales , Carcinoma de Ehrlich/metabolismo , Globinas/biosíntesis , Cinética , Ratones , Peso Molecular , Oxidación-Reducción , Polirribosomas/metabolismo , Conejos , Reoviridae/metabolismo , Reticulocitos/metabolismo
15.
Acta Crystallogr C ; 57(Pt 12): 1410-4, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11740100

RESUMEN

The title compounds, 1-ferrocenylmethyl-2-(4-methoxyphenyl)-1H-benzimidazole, [Fe(C5H5)(C20H17N2O)], (I), and 2-(3,4-dimethoxyphenyl)-1-ferrocenylmethyl-1H-benzimidazole, [Fe(C5H5)(C21H19N2O2)], (II), are model electroactive compounds for anion sensor and antimalarial applications. Distortions from the ideal 120 degrees angle about the MeO-C-C groups are evident, with angles of 115.1 (2) and 125.0 (2) degrees in (I), and 115.9 (2) and 124.6 (2) degrees, and 115.7 (2) and 125.1 (2) degrees in (II). The main intermolecular hydrogen bonds in (I) comprise C-H.N and C-H.pi(C5H5) interactions, while in (II), only weak C-H.pi(imidazole) and C-H.pi(arene) interactions are present.

16.
Ann Vasc Surg ; 3(1): 14-9, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2713227

RESUMEN

Carotid atherosclerosis occurring secondary to cervical irradiation is known to produce stroke. Transient neurologic symptoms have necessitated surgical intervention to prevent stroke despite concern over technical problems, wound healing, operative risks, and uncertain therapeutic outcome. With this report, 26 surgical procedures in 20 patients are now documented in the literature (12 men--60%; eight women--40%). Mean age of these patients (56 years) was 10 years younger than carotid surgery patients with no prior radiation history. No relationship was noted between elevated serum cholesterol and the subsequent development of radiation-induced carotid atherosclerosis. Surgical procedures performed included carotid endarterectomy in 17 cases (65%) and arterial bypass in nine (35%). The combination of radiation therapy and previous neck surgery, including prior radical neck dissection, did not adversely influence operability. Surgical outcome was uniformly good with only one stroke (4%) documented in the perioperative period. Longer follow-up on our six cases (mean two years) disclosed neither new clinical symptoms nor the development of hemodynamically significant restenosis.


Asunto(s)
Enfermedades de las Arterias Carótidas/etiología , Arteriosclerosis Intracraneal/etiología , Radioterapia/efectos adversos , Adulto , Anciano , Prótesis Vascular , Arterias Carótidas/cirugía , Enfermedades de las Arterias Carótidas/cirugía , Trastornos Cerebrovasculares/prevención & control , Endarterectomía , Femenino , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Arteriosclerosis Intracraneal/cirugía , Masculino , Persona de Mediana Edad
17.
EMBO J ; 8(1): 183-91, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2714250

RESUMEN

A hybrid mouse major urinary protein (MUP)/SV40 T antigen gene was microinjected into fertilized mouse embryos and the resulting transgenic mice analyzed for the regulated expression of the transgene. Available evidence indicates that the MUP gene used for the hybrid gene construct is expressed in both male and female liver and possibly mammary gland. Three different transgenic lines exhibited a consistent pattern of tissue specific expression of the transgene. As a consequence of transgene expression and T antigen synthesis in the liver, both male and female transgenic animals developed liver hyperplasia and tumors. Transgene expression and liver hyperplasia commenced at approximately 2-4 weeks of age, the same time that MUP gene expression is first detected in the liver. The expression of the transgene resulted in an immediate strong suppression of liver MUP mRNA levels but had relatively little effect on other liver specific mRNAs. From 4 to 8 weeks, the liver increased several fold in size, relative to non-transgenic littermates. Definitive tumor nodules were not apparent until 8-10 weeks. The transgene was also consistently found to be expressed in the skin sebaceous glands and the preputial gland, a modified sebaceous gland. The expression of the transgene in the skin sebaceous glands is consistent with the presence of MUP mRNA in the skin and a putative role for MUPs in the transport and excretion of small molecules. Occasional expression of the transgene in other tissues (kidney and mammary connective tissues) was also noted.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Antígenos Transformadores de Poliomavirus/biosíntesis , Neoplasias Hepáticas Experimentales/etiología , Proteínas/fisiología , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes/biosíntesis , Animales , Antígenos Transformadores de Poliomavirus/genética , Antígenos Transformadores de Poliomavirus/fisiología , Femenino , Genes Sintéticos , Hiperplasia , Riñón/análisis , Hígado/análisis , Hígado/patología , Hepatopatías/etiología , Hepatopatías/genética , Neoplasias Hepáticas Experimentales/genética , Masculino , Glándulas Mamarias Animales/análisis , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Transgénicos , Neoplasias Experimentales/etiología , Neoplasias Experimentales/genética , Especificidad de Órganos , Lesiones Precancerosas/etiología , Lesiones Precancerosas/genética , Proteínas/genética , Secuencias Reguladoras de Ácidos Nucleicos , Glándulas Sebáceas/análisis
18.
Clin Exp Hypertens A ; 4(11-12): 2185-91, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6756690

RESUMEN

For human samples quantitation of inactive renin can be carried out by incubation with trypsin under defined conditions, followed by RIA of the activated renin. For dog samples we were unable to obtain evidence for the presence of inactive renin in the plasma by using trypsin, acid or cold to activate. Increases in angiotensin generation did occur with trypsin and acid but they both changed renin substrate such that the rate of angiotensin generation by exogenous renin was increased at pH 7.4, but not at pH 5.7; also following trypsin or acid treatment angiotensin I was cleaved from renin substrate by a plasma acid protease that normally does not cleave renin substrate in plasma. Therefore, for dog samples, it is important to demonstrate that an increase in the rate of angiotensin generation is indeed due to activation of inactive renin and not to changes in pH optimum of renin with angiotensinogen or to the effect of another enzyme.


Asunto(s)
Precursores Enzimáticos/sangre , Renina/sangre , Animales , Frío , Perros , Activación Enzimática , Humanos , Concentración de Iones de Hidrógeno , Cinética , Tripsina/metabolismo
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