RESUMEN

PURPOSE: To assess the effect of Glaucoma awareness, knowledge, and anxiety on patients under visual field analysis by Humphrey's visual field analyzer (HFA) and optical coherence tomography(OCT). METHODS: This prospective comparative cohort study included glaucoma patients undergoing HFA (Group A)(n = 150) and OCT(Group B) (n = 150). Each group consisted of 75 newly diagnosed patients and 75 patients who were on follow-up. Participants completed State trait anxiety inventory form Y2(STAI) before and after the test to assess pre-test and intra-test anxiety. Another validated and structured questionnaire was used to assess patient awareness and knowledge of glaucoma. Anxiety scores were used to make correlations and comparisons between the two groups and also against visual field reliability indices. The impact of awareness on anxiety scores and its correlation with reliability indices were also determined. RESULTS: Overall pretest and intratest anxiety scores in patients undergoing HFA were 52.39(9.5) and 52.45(8.6)and OCT 53.04(8.0) and 53.83(8.2) respectively.Pretest anxiety was less in follow-up patients of both groups(Group A-51.04,Group B-52.72).There was no statistically significant difference between the groups(pretest p = 0.52,Intratest p = 0.15). Anxiety score was found to be significantly high in female participants(54.07,p = 0.01)and those without awareness(p < 0.001). Patients with education of graduation and above in group B had significantly lower anxiety scores(p = 0.007). CONCLUSION: Anxiety levels induced by both diagnostic modalities HFA and OCT appear to be similar and it does not affect the reliability indices.Anxiety score was higher in female participants and participants lacking disease awareness.

RESUMEN

Pregnancy in a patient with acromegaly is a rare occurrence. Here in, we report a patient with acromegaly who presented to us in the 2(nd) trimester of pregnancy with visual loss in the right eye. Her vision improved after surgery. She went on to have an uneventful pregnancy and delivered a term baby, by caesarian section. One year following her delivery, she received stereotactic radiotherapy. Subsequent follow-up revealed that her tumor had regressed and her IGF-1 levels had normalized.

RESUMEN

AIM: To assess the extent and severity of coronary artery disease (CAD) in 200 consecutive patients aged 35 years or less undergoing diagnostic coronary angiography. PATIENTS AND METHODS: Findings in these 200 patients (≤ 35 years of age) were analyzed to find the extent and severity of CAD. The mean age was 31.69 (±3.76) years. Majority were males (94%) and from the Arab ethnicity (70.5%). RESULT: Smoking (71%) and history of premature CAD (27%) were the most frequent risk factors (RF). History of previous ST elevation myocardial infarction (MI) was present in 68%. Anterior wall MI was the most frequent location (63.3%). The majority (54.3%) had moderate or large size MI. Ejection fraction (EF) less than 50% was noted in 30.3%. Left main or triple vessel CAD was seen in 15%. One- and two-vessel CAD was seen in 32.5% and 19% patients, respectively. Coronary angiogram was completely normal in 23.5%. The majority (54.5%) were treated conservatively and the rest (45.5%) needed percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). The mean number of stents used was 1.3 ± 0.67 and the mean length of stents used was 20.3 ± 12.6 mm. CONCLUSION: The extent and severity of CAD was very significant in this subgroup of very young (≤35 years) Asian patients. Smoking was the main risk factor and half of the patients needed either PCI or CABG.

RESUMEN

We report pheochromocytoma and haemophilia occurring in a 19-year-old South Indian man. To the best of our knowledge, this case is the first of its kind to be reported in the medical literature. The patient had bilateral adrenal pheochromocytomas with an extradrenal pheochromocytoma on the left side, and was successfully operated on after optimal preoperative blood pressure control and factor VIII support.

Asunto(s)

Hemofilia A/complicaciones , Feocromocitoma/complicaciones , Glándulas Suprarrenales/cirugía , Adrenalectomía/métodos , Adulto , Presión Sanguínea , Factor VIII/uso terapéutico , Humanos , Masculino , Necrosis , Feocromocitoma/cirugía , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento

RESUMEN

Heparan sulfate formation occurs by the copolymerization of glucuronic acid (GlcA) and N-acetylglucosamine (GlcNAc) residues. Recent studies have shown that these reactions are catalyzed by a copolymerase encoded by EXT1 and EXT2, members of the exostosin family of putative tumor suppressors linked to hereditary multiple exostoses. Previously, we identified a collection of Chinese hamster ovary cell mutants (pgsD) that failed to make heparan sulfate (Lidholt, K., Weinke, J. L., Kiser, C. S., Lugemwa, F. N., Bame, K. J., Cheifetz, S., Massagué, J., Lindahl, U., and Esko, J. D. (1992) Proc. Natl. Acad. Sci. U. S. A. 89, 2267-2271). Here, we show that pgsD mutants contain mutations that either alter GlcA transferase activity selectively or that affect both GlcNAc and GlcA transferase activities. Expression of EXT1 corrects the deficiencies in the mutants, whereas EXT2 and the related EXT-like cDNAs do not. Analysis of the EXT1 mutant alleles revealed clustered missense mutations in a domain that included a (D/E)X(D/E) motif thought to bind the nucleotide sugar from studies of other transferases. These findings provide insight into the location of the GlcA transferase subdomain of the enzyme and indicate that loss of the GlcA transferase domain may be sufficient to cause hereditary multiple exostoses.

Asunto(s)

Glucuronosiltransferasa/metabolismo , Heparitina Sulfato/genética , Mutación Missense , N-Acetilglucosaminiltransferasas/química , N-Acetilglucosaminiltransferasas/metabolismo , Acetilglucosamina/metabolismo , Secuencia de Aminoácidos , Animales , Células CHO , Clonación Molecular , Cricetinae , Exostosis Múltiple Hereditaria , Humanos , Cinética , Ratones , Datos de Secuencia Molecular , N-Acetilglucosaminiltransferasas/genética , Proteínas/metabolismo , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido

RESUMEN

Asn-52 of rat cytochrome c and baker's yeast iso-1-cytochrome c was changed to isoleucine by site-directed mutagenesis and the mutated proteins expressed in and purified from cultures of transformed yeast. This mutation affected the affinity of the haem iron for the Met-80 sulphur in the ferric state and the reduction potential of the molecule. The yeast protein, in which the sulphur-iron bond is distinctly weaker than in vertebrate cytochromes c, became very similar to the latter: the pKa of the alkaline ionization rose from 8.3 to 9.4 and that of the acidic ionization decreased from 3.4 to 2.8. The rates of binding and dissociation of cyanide became markedly lower, and the affinity was lowered by half an order of magnitude. In the ferrous state the dissociation of cyanide from the variant yeast cytochrome c was three times slower than in the wild-type. The same mutation had analogous but less pronounced effects on rat cytochrome c: it did not alter the alkaline ionization pKa nor its affinity for cyanide, but it lowered its acidic ionization pKa from 2.8 to 2.2. These results indicate that the mutation of Asn-52 to isoleucine increases the stability of the cytochrome c closed-haem crevice as observed earlier for the mutation of Tyr-67 to phenylalanine [Luntz, Schejter, Garber and Margoliash (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 3524-3528], because of either its effects on the hydrogen-bonding of an interior water molecule or a general increase in the hydrophobicity of the protein in the domain occupied by the mutated residues. The reduction potentials were affected in different ways; the Eo of rat cytochrome c rose by 14 mV whereas that of the yeast iso-1 cychrome c was 30 mV lower as a result of the change of Asn-52 to isoleucine.

Asunto(s)

Asparagina/genética , Grupo Citocromo c/genética , Hemo/metabolismo , Isoleucina/genética , Mutagénesis Sitio-Dirigida , Animales , Asparagina/metabolismo , Cianuros/metabolismo , Grupo Citocromo c/metabolismo , Concentración de Iones de Hidrógeno , Iones , Isoleucina/metabolismo , Oxidación-Reducción , Ratas , Saccharomyces cerevisiae/enzimología

RESUMEN

The residue asparagine-52 of rat cytochrome c and baker's yeast iso-1-cytochrome c was mutated to isoleucine by site-directed mutagenesis, and the unfolding of the wild-type and mutant proteins in urea or guanidinium chloride solutions was studied. Whereas the yeast mutant cytochrome unfolded in 4-7 M urea with a rate constant (k) of 1.7 x 10(-2) s-1, the rat mutant protein unfolded with k = 5.0 x 10(-2) s-1, followed by a slow partial refolding with k = 5.0 x 10(-4) s-1. Denaturant titrations indicated that the mutation increased the stability of the yeast cytochrome by 6.3 kJ (1.5 kcal)/mol, while it decreased that of the rat protein by 11.7 kJ (2.8 kcal)/mol. These results probably reflect structural differences between yeast iso-1 and vertebrate cytochromes c in the vicinity of the Asn-52 side chain.

Asunto(s)

Asparagina , Grupo Citocromo c/química , Isoleucina , Pliegue de Proteína , Saccharomyces cerevisiae/metabolismo , Secuencia de Aminoácidos , Animales , Calorimetría , Grupo Citocromo c/metabolismo , Estabilidad de Medicamentos , Cinética , Mutagénesis Sitio-Dirigida , Desnaturalización Proteica , Ratas , Urea

RESUMEN

A complete protocol for the expression of recombinant cytochrome c genes from yeast, Drosophila melanogaster, and rat in a yeast strain, GM-3C-2, which does not express its own cytochromes c is described. The construction of the expression vectors, transformation and large-scale growth of the yeast, and preparation and purification of the recombinant cytochromes c are described. It was found that, contrary to the way yeast modifies its own cytochromes c, the recombinant proteins were partially acetylated at their N-terminus, except for the drosophila protein, which remained entirely unblocked. Furthermore, the yeast and rat proteins were close to fully trimethylated at lysine 72, while the drosophila protein could be separated chromatographically into forms containing tri-, di-, mono-, and unmethylated lysine 72 showing corresponding resonances in the NMR spectrum. These observations emphasize that, in employing expression procedures to obtain native or mutant forms of cytochrome c, it is essential to identify the variety and extent of post-translational modifications and to separate the preparation into pure monomolecular species. Otherwise, it may become impossible to distinguish between the influence of a site-directed mutation and unexamined post-translational modifications.

Asunto(s)

Grupo Citocromo c/genética , Procesamiento Proteico-Postraduccional , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromatografía Líquida de Alta Presión , Grupo Citocromo c/biosíntesis , Grupo Citocromo c/aislamiento & purificación , Drosophila melanogaster/química , Drosophila melanogaster/genética , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Ratas/genética , Proteínas Recombinantes/biosíntesis , Saccharomyces cerevisiae/química

RESUMEN

The methionine 80 sulfur-heme iron bond of rat cytochrome c, whose stability is decreased by mutating the phylogenetically invariant residue proline 30 to alanine and increased when tyrosine 67 is changed to phenylalanine, recovers its wild-type characteristics when both substitutions are performed on the same molecule. Titrations with urea, analyzed according to the heteropolymer theory [Alonso, D. O. V., & Dill, K. A. (1991) Biochemistry 30, 5974-5985], indicate that both single mutations increase the solvent exposure of hydrophobic groups in the unfolded state, while in the double mutant this conformational perturbation disappears. Similar increases in solvent exposure of hydrophobic groups are observed when the sulfur-iron bond of the wild-type protein is broken by alkylation of the methionine sulfur, by high pH, or by binding the heme iron with cyanide. The compensatory effects of the two single mutations do not extend to the overall stability of the protein. The added loss of conformational stability due to the single mutations amounts to 7.3 kcal/mol out of the 9 kcal/mol representing the overall free energy of stabilization of the native conformation of the wild-type protein. The folded conformation of the doubly mutated protein is only 2 kcal/mol less stable than that of the wild type. These results indicate that the double mutant protein is able to retain the essential folding pattern of cytochrome c and the thermodynamic stability of the methionine sulfur-heme iron bond, in spite of structural differences that weaken the overall stability of the molecule.

Asunto(s)

Grupo Citocromo c/química , Mutagénesis Sitio-Dirigida , Conformación Proteica , Secuencia de Aminoácidos , Animales , Calorimetría , Grupo Citocromo c/genética , Estabilidad de Medicamentos , Guanidina , Guanidinas/farmacología , Cinética , Modelos Moleculares , Datos de Secuencia Molecular , Desnaturalización Proteica , Proteínas Recombinantes/química , Urea/farmacología

RESUMEN

Our current incomplete picture of the earliest events in HSV infection may be summarized as follows. The initial interaction of virus with cells is the binding of virion gC to heparan sulfate moieties of cell surface proteoglycans. Stable binding of virus to cells may require the interaction of other virion glycoproteins with other cell surface receptors as well (including the interaction of gB with heparan sulfate). Penetration of virus into the cell is mediated by fusion of the virion envelope with the cell plasma membrane. Events leading up to this fusion require the action of at least three viral glycoproteins (gB, gD and gH), one or more of which may interact with specific cell surface components. It seems likely that binding of gB to cell surface heparan sulfate may occur and may be important in the activation of some event required for virus penetration. Heparan sulfate is present not only as a constituent of cell surface proteoglycans but also as a component of the extracellular matrix and basement membranes in organized tissues. In addition, body fluids contain both heparin and heparin-binding proteins, either of which can prevent the binding of HSV to cells (WuDunn and Spear, 1989). As a consequence, the spread of HSV infection is probably influenced, not only by immune responses to the virus, but also by the probability that virus will be entrapped or inhibited from binding to cells by extracellular forms of heparin or heparan sulfate.

Asunto(s)

Heparitina Sulfato/metabolismo , Receptores Virales/metabolismo , Simplexvirus/metabolismo , Secuencia de Aminoácidos , Animales , Liasa de Heparina , Humanos , Datos de Secuencia Molecular , Polisacárido Liasas/metabolismo , Simplexvirus/clasificación , Simplexvirus/genética , Proteínas del Envoltorio Viral/genética

RESUMEN

Drosophila melanogaster and rat cytochromes c in which proline-30 was converted to alanine or valine were expressed in a strain of baker's yeast, Saccharomyces cerevisiae, where they sustained aerobic growth. The mutations had no significant effect on the spectra or redox potentials but altered drastically the stability of the bond between the methionine-80 sulfur and the heme iron, as judged by four criteria: (i) the alkaline pKa values of the 695-nm band of the ferric form of the mutant proteins decreased by almost 1 pH unit as compared to the wild types; (ii) the acid pKa values increased by 0.5 to 1.2 pH units; (iii) the 695-nm band half-disappeared at temperatures 10-20 degrees C lower in the mutant proteins than in the wild types; and (iv) the 695-nm band of the mutant proteins was susceptible to concentrations of urea that had little influence on their overall structure. The valine-substituted rat cytochrome c had properties intermediate between those of the wild type and the alanine mutant. The destabilized coordinative bond is located in space a long distance from the mutation site. It is suggested that the mutations weaken the hydrogen bond between the carbonyl of residue 30 and the imino group of the imidazole of histidine-18, modifying the bonding of the heme iron by that imidazole, which, in turn, through a trans effect, weakens the bond between the heme iron and the other axial ligand, the sulfur of methionine-80. Alternatively, the effect of the mutations may be propagated allosterically along the peptide chain.

Asunto(s)

Grupo Citocromo c/química , Alanina , Animales , Sitios de Unión , Clonación Molecular , Drosophila melanogaster , Hemo , Calor , Prolina , Conformación Proteica/efectos de los fármacos , Ratas , Proteínas Recombinantes , Análisis Espectral , Relación Estructura-Actividad , Urea/farmacología , Valina

RESUMEN

To examine the amino acid sequence requirements for the biphasic association of Drosophila melanogaster apocytochrome c with mouse liver mitochondria in vitro, recombinant constructs of the protein were prepared. Removal of the C-terminal sequence to residue 58 had little influence, but truncation to residue 50 decreased the association to low levels and removal to residue 36 was even more effective. However, a mutant missing the segment between residues 35 and 66 was fully functional, but, when the C-terminal segment from residue 36 was replaced with a noncytochrome c sequence, the high-affinity phase of the association was lost. A mutant in which residues 90, 91, 92, 96, and 100 were replaced by lysine, leucine, proline, proline, and proline, respectively, to prevent the possible formation of the C-terminal alpha-helix and another mutant in which the C-terminal segment from residue 90 to residue 120 was a noncytochrome c sequence had normal association. In contrast, replacing lysine-5, -7, and -8 by glutamine, glutamic acid, and asparagine, respectively, resulted in loss of the high-affinity phase. The same mutations in the apoprotein lacking the segment between residues 35 and 66 caused, in addition, a decrease of the low-affinity phase association. Thus, the N-terminal region is most critical for apocytochrome c association, but alternative segments of the central and/or C-terminal region can be utilized, where noncytochrome c sequences are ineffective. These results emphasize the wide disparity between the structural requirements for association with mitochondria and for the production of a functional holoprotein.

Asunto(s)

Apoproteínas/genética , Grupo Citocromo c/genética , Mitocondrias Hepáticas/metabolismo , Secuencia de Aminoácidos , Animales , Apoproteínas/metabolismo , Deleción Cromosómica , Clonación Molecular , Grupo Citocromo c/metabolismo , Citocromos c , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Cinética , Ratones , Datos de Secuencia Molecular , Mutación , Conformación Proteica , Ratas

RESUMEN

Twenty-two patients with brucella spondylitis and neurobrucellosis were studied during a 2-year period. The diagnosis was based on history of exposure, compatible signs and symptoms, high antibody titre and/or positive culture of a clinical specimen(s). Spondylitis was confirmed by plain radiographs, bone scan, CT and in some cases by histology. Neurobrucellosis was confirmed by CSF examination and culture, myelography, NCV, EMG and CT head. The spondylitis was early in 4 cases, chronic active in 12, smouldering "partially healed" in 3 and healed in 3 cases. Of these, 15 patients (68%) had neurological complications of various types. Plain radiographs were not a good index of activity of spondylitis. Tc99 bone scan was not specific and it remained positive long after the completion of therapy. CT was superior in revealing details of bone destruction, soft tissue swelling and entrapment of nerve roots and cord. The 3 modalities were complementary. Spondylitis is commonly associated with neurobrucellosis and symptoms of one may over shadow those of the other and in some cases neurobrucellosis may be subclinical. In all cases of spondylitis, a thorough search for neurobrucellosis should be made and vice versa. Prolonged treatment with a combination of 3 anti-brucella drugs is recommended and prolonged follow-up is necessary.

Asunto(s)

Brucelosis/complicaciones , Vértebras Lumbares/diagnóstico por imagen , Enfermedades del Sistema Nervioso/microbiología , Espondilitis/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brucelosis/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/fisiopatología , Espondilitis/complicaciones , Espondilitis/diagnóstico por imagen , Estreptomicina/uso terapéutico , Tomografía Computarizada por Rayos X

RESUMEN

A highly active angiotensin-producing enzyme (enzyme III) was obtained from the serum of bilaterally nephrectomized dogs by acid treatment and ammonium sulfate fractionation. An inactive precursor (proenzyme III) was converted to enzyme III during prolonged storage (or by treatment with acid or with cathepsin G or by incubation at 38 degrees C as described in the following paper). Enzyme III reacted maximally at pH 7.7 and it produced up to 400 ng of angiotensin II/mL serum/h (i.e., amounts 4000 times higher than that generated by the endogenous renin present in serum after bilateral nephrectomy). Enzyme III produced angiotensin II at identical rates when either dog angiotensinogen or angiotensin I was used as substrate, but the rate was 710 times higher with synthetic tetradecapeptide renin substrate. Enzyme III is not identical to renin, cathepsin G, tonin, enzyme I, enzyme II, the calcium-dependent angiotensin I-converting enzyme, or the calcium-independent carboxy peptidase, which acts by sequential cleavage of angiotensin I. Enzyme III was inhibited by alpha-1-antitrypsin, diisopropyl fluorophosphate, and lima bean trypsin inhibitor (hence it is a serine proteinase). It was not inhibited by Captopril, Teprotide, or Enalapril. It had been reported previously that cathepsin G released from neutrophil granulocytes, by producing high local concentrations of angiotensin II, may provide a mobile means for modulating blood flow in tissue microvasculature during the inflammatory response. The present study offers a new, additional pathway, by enzyme III, for a similar rapid formation of angiotensin II from serum protein substrate or angiotensin I.

Asunto(s)

Angiotensina II/biosíntesis , Precursores Enzimáticos/sangre , Serina Endopeptidasas/sangre , Antagonistas Adrenérgicos alfa/farmacología , Angiotensina I/metabolismo , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Catepsina G , Catepsinas/farmacología , Perros , Epinefrina/metabolismo , Femenino , Masculino , Nefrectomía , Norepinefrina/metabolismo , Serina Endopeptidasas/aislamiento & purificación , Inhibidores de Serina Proteinasa , alfa 1-Antitripsina/farmacología

RESUMEN

Enzyme III and its inactive precursor proenzyme III have been obtained from the acidified serum of bilaterally nephrectomized dogs. Enzyme III occurs in a concentration producing angiotensin at a rate 50 times higher than the residual renin. Much higher concentrations of enzyme III have been obtained by three activation procedures: a) by storage for several months in the frozen state; b) by treatment at 0 degrees C and pH 3.0; or c) by incubation at 38 degrees C and pH 7.7. These procedures yielded levels of enzyme III that produced up to 400 ng angiotensin II/mL serum/h, i.e., 4000 times higher than the endogenous renin. Of further significance, the angiotensin II produced by enzyme III represents the octapeptide with the highest known vasoconstrictor activity. This is in contrast to renin, enzyme I, and enzyme II, all of which produced angiotensin I, the decapeptide without appreciable vasoconstrictor activity. The endogenous activating enzyme has been identified as cathepsin G by the following six experimental observations: both the endogenous activating enzyme and exogenous cathepsin G produced enzyme III from proenzyme III according to the same unusual sigmoid kinetics; they were blocked identically by antibody to human cathepsin G. Also, both were inhibited similarly by alpha-1-antitrypsin, lima bean trypsin inhibitor, diisopropyl fluorophosphate, or by an inhibitor present in dog serum. Thus, removal of this inhibitor and activation of proenzyme III by endogenous or by added cathepsin G are prerequisites to obtaining enzyme III; this provides a novel mechanism for the rapid formation of angiotensin II from serum protein substrate or from angiotensin I.

Asunto(s)

Angiotensina II/biosíntesis , Catepsinas/metabolismo , Precursores Enzimáticos/sangre , Serina Endopeptidasas/sangre , Animales , Catepsina G , Perros , Activación Enzimática , Femenino , Cinética , Masculino , Nefrectomía , Valores de Referencia , Temperatura , alfa 1-Antitripsina/metabolismo

RESUMEN

Diagnosis of brucella meningitis was made in 10 patients by serological tests on blood and cerebrospinal fluid using Rose Bengal, standard agglutination, indirect immunofluorescent and enzyme-linked immunosorbent assay (ELISA) tests and by blood and CSF culture. All patients had significantly elevated antibody titres. In three Br. melitensis was isolated both from blood and CSF and in a further three from blood only. Eight patients were 30 years old or less and seven were female. Seven patients had a history of contact with livestock and had consumed raw milk. Meningitis occurred in five, meningoencephalitis with hemiplegia in one, paraplegia and cranial nerve palsies in one and psychosis and/or nightmares in three. Transient Parkinsonism was seen in one patient and generalized rigidity and non-Parkinsonian tremors in another. Computerized tomography revealed ventricular dilation in one patient and punctate hyperdense, non-enhancing shadows in the lentiform nuclei in two others. Treatment with a combination of tetracycline, rifampicin and streptomycin was successful.

Asunto(s)

Brucelosis/diagnóstico , Meningitis/diagnóstico , Adolescente , Adulto , Anciano , Anticuerpos Antibacterianos/análisis , Brucelosis/inmunología , Brucelosis/metabolismo , Femenino , Humanos , Masculino , Meningitis/inmunología , Meningitis/metabolismo , Persona de Mediana Edad , Estudios Prospectivos , Tomografía Computarizada por Rayos X

RESUMEN

A highly active angiotensin-producing enzyme (enzyme II) was obtained from dog serum by acid treatment and fractionation to remove angiotensinase and converting enzyme, separate an inhibitor, and convert an inactive precursor (proenzyme II) to enzyme II. Proenzyme II was found to be converted to enzyme II by an endogenous activating enzyme identified as plasmin. Conversion was also caused by the interaction of bacterial streptokinase with human proactivator, by trypsin, and by an activator formed from liver tissue extract and dog serum. Neither plasma kallikrein nor the labile, human extrinsic tissue-type plasminogen activator induced activation. The inhibitor, which normally blocks the activation of proenzyme II, was unusually stable against high temperatures and extremes of pH, and it was not identical to any of the six known protease inhibitors of serum. Enzyme II was not identical to other angiotensin-producing enzymes such as enzyme I, renin, cathepsin D, pepsin, plasmin, tonin, or cathepsin G. Enzyme II reacted maximally at pH 4.7 and produced up to 2250 ng of angiotensin I/ml serum/hr from the substrate of dog serum (i.e., amounts 3200-fold higher than that produced by endogenous renin of normal dog serum). Since at pH 7.2, angiotensin I formation is still about 30 times higher than that of renin, enzyme II may be physiologically active under some conditions.

Asunto(s)

Endopeptidasas/aislamiento & purificación , Animales , Perros , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Precursores Enzimáticos/aislamiento & purificación , Femenino , Masculino

RESUMEN

Immunization with renin from the kidneys of hog, beef, dog, rabbit and man induced the formation of a highly active enzyme (enzyme I) in the serum of dogs, guinea pigs, rabbits and rats. Enzyme I produces angiotensin I maximally at pH 4.7, up to 2900 ng/ml serum/h, i.e. at a rate 2500 times higher than the endogenous renin of normal serum. At pH 7.2 the angiotensin I production by enzyme I is about 16 to 28 times higher than that of plasma renin. Enzyme I is produced by immunization with renin and not by other kidney proteins. Enzymatically-active renin is required and separate mechanisms are involved in the formation of enzyme I and antirenin. Enzyme I is not identical to renin, pepsin, cathepsin D, plasmin, tonin or cathepsin G and it is inhibited by pepstatin, but not by diisopropyl fluorophosphate.

Asunto(s)

Carboxipeptidasas/biosíntesis , Inmunización , Lisina Carboxipeptidasa/biosíntesis , Renina/inmunología , Animales , Anticuerpos/fisiología , Catepsina D/antagonistas & inhibidores , Catepsina D/metabolismo , Catepsina G , Catepsinas/metabolismo , Bovinos , Perros , Fibrinolisina/metabolismo , Cobayas , Humanos , Concentración de Iones de Hidrógeno , Lisina Carboxipeptidasa/antagonistas & inhibidores , Lisina Carboxipeptidasa/sangre , Pepsina A/antagonistas & inhibidores , Pepsina A/metabolismo , Pepstatinas/farmacología , Peptidil-Dipeptidasa A/metabolismo , Conejos , Ratas , Renina/metabolismo , Serina Endopeptidasas , Especificidad por Sustrato , Porcinos

Asunto(s)

Glándula Tiroides/fisiología , Hormonas Tiroideas/sangre , Tirotropina/sangre , Femenino , Humanos , Hipertiroidismo/terapia , Masculino , Pruebas de Función de la Tiroides

RESUMEN

In a preliminary study, 11 male patients with lepromatous leprosy were evaluated with regard to endocrinopathy and hormonal status. Basal circulating hormone levels were estimated with a view to correlating the biochemical findings and clinical features. Thyroid hormones T3 and T4, Free Thyroxine Index (FTI), TSH, and cortisol were within normal limits, indicating that further study of these hormones would not be worthwhile. The finding of elevated levels of prolactin as well as the gonadotrophins LH and FSH, however, promises to yield more valuable information if studied in greater detail in a larger group of patients.

Asunto(s)

Hormonas/sangre , Lepra/fisiopatología , Adulto , Disfunción Eréctil/etiología , Hormona Folículo Estimulante/sangre , Ginecomastia/etiología , Humanos , Hidrocortisona/sangre , Lepra/complicaciones , Hormona Luteinizante/sangre , Masculino , Orquitis/etiología , Prolactina/sangre , Hormonas Tiroideas/sangre