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H Rodriguez

Publications and source records attributed to H Rodriguez.

At least 91 records · Page 5Linked to original sources
PubMed1987

Amino-acid sequence of human alpha 2-antiplasmin.

The amino-acid sequence of human alpha 2-antiplasmin was determined by Edman degradation of peptides purified from CNBr, tryptic and chymotryptic digests. Of the total sequence of 452 amino acids of mature alpha 2-antiplasmin, as deduced from the cDNA sequence [Holmes et al. (1987) J. Biol. Chem. 262, 1659-1664], 444 residues were identified by amino-acid sequencing. Two differences were found between the peptide and cDNA analyses (Gly instead of Leu at position 10 and Gly instead of Ser at position 369). alpha 2-Antiplasmin contains two disulfide bridges (Cys64-Cys104 and Cys31-Cys113) and four glucosamine-based carbohydrate chains attached to Asn87, Asn256, Asn270 and Asn277. alpha 2-Antiplasmin is homologous with 12 other proteins belonging to the serine protease inhibitor (serpin) superfamily.

Amino Acid Sequence↗
PubMed1987

Structure of the precursor to an enzyme mediating COOH-terminal amidation in peptide biosynthesis.

Many bioactive peptides terminate with an amino acid alpha-amide at their COOH terminus. The enzyme responsible for this essential posttranslational modification is known as peptidyl-glycine alpha-amidating monooxygenase or PAM. We identified cDNAs encoding the enzyme by using antibodies to screen a bovine intermediate pituitary lambda gt11 expression library. Antibodies to a beta-galactosidase/PAM fusion protein removed PAM activity from bovine pituitary homogenates. The 108,207 dalton protein predicted by the complete cDNA is approximately twice the size of purified PAM. An NH2-terminal signal sequence and short propeptide precede the NH2 terminus of purified PAM. The sequences of several PAM cyanogen bromide peptides were localized in the NH2-terminal half of the predicted protein. The cDNA encodes an additional 430 amino acid intragranular domain followed by a putative membrane spanning domain and a hydrophilic cytoplasmic domain. The forms of PAM purified from bovine neurointermediate pituitary may be generated by endoproteolytic cleavage at a subset of the 10 pairs of basic amino acids in the precursor. High levels of PAM mRNA were found in bovine pituitary and cerebral cortex. In corticotropic tumor cells, levels of PAM mRNA and pro-ACTH/endorphin mRNA were regulated in parallel by glucocorticoids and CRF.

Amides↗
PubMed1986

Proteolytic processing of human factor VIII. Correlation of specific cleavages by thrombin, factor Xa, and activated protein C with activation and inactivation of factor VIII coagulant activity.

Human factor VIII was isolated from commercial factor VIII concentrates and found to consist of multiple polypeptides with molecular weights ranging from 80 000 to 210 000. Immunological and amino acid sequence data identified these polypeptides as subunits of factor VIII. N-Terminal amino acid sequence analysis determined that the Mr 210 000 and 80 000 proteins are derived from the N- and C-terminal portions of factor VIII, respectively; Mr 90 000-180 000 polypeptides are derived from the Mr 210 000 polypeptide by C-terminal cleavages. Treatment of purified factor VIII with thrombin resulted in proteolysis of Mr 80 000-210 000 proteins and the generation of polypeptides of Mr 73 000, 50 000, and 43 000. Maximum coagulant activity of thrombin-activated factor VIII was correlated with the generation of these polypeptides. The proteolysis as well as activation of factor VIII by thrombin was found to be markedly dependent on CaCl2 concentration. Proteolysis of factor VIII with activated protein C (APC) resulted in degradation of the Mr 90 000-210 000 proteins with the generation of an Mr 45 000 fragment. This cleavage correlated with inactivation of factor VIII by APC. The Mr 80 000 protein was not degraded by APC. Factor Xa cleaved the Mr 80 000-210 000 factor VIII proteins, resulting in the generation of fragments of Mr 73 000, 67 000, 50 000, 45 000, and 43 000. Factor Xa was found to initially activate and subsequently inactivate factor VIII.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1986

The avian beta-adrenergic receptor: primary structure and membrane topology.

Partial amino acid sequence information allowed the isolation of cDNA clones encoding the turkey erythrocyte beta-adrenergic receptor. Antisera raised against synthetic peptides encoded by the cDNA crossreacted with the purified receptor and appropriate tryptic fragments, confirming the identity of the cDNA. The receptor is composed of 483 amino acids and has a molecular mass of 54 kDa. Its sequence suggests that it is arranged predominantly in seven membrane-spanning sequences and a long cytoplasmic carboxyl-terminal domain. The extracellular amino-terminal domain contains a consensus sequence for N-glycosylation. The beta-adrenergic receptor displays overall structural similarity and weak sequence homology with rhodopsin. Because both proteins act by regulating GTP-binding proteins, a compact structure based on seven membrane-spanning regions may be a general model for receptors that act on G proteins.

Amino Acid Sequence↗
PubMed1986

Carbohydrate malabsorption in black and Hispanic dialysis patients.

Patients on chronic hemodialysis have decreased food intake and decreased fat stores. Malabsorption of carbohydrates such as lactose, sorbitol, or fructose cause functional bowel symptoms. The aim of this study was to assess the role of carbohydrate malabsorption in the nutritional abnormalities of chronic hemodialysis (CHD). Eleven patients on dialysis (six Hispanic, five black Americans) were studied, compared to 11 healthy volunteers age-, race-, and sex-matched. Lactulose 10 g (transit time), lactose 12.5 g, sorbitol 5 g, and fructose 37.5 g were tested fasting. Breath [H2] was measured 4 h postprandially by gas chromatograph analysis. Positive test was defined as 20 ppm [H2] above baseline. Weight, height, and triceps skinfold were measured. One hundred percent of CHD patients were below the 50th percentile for triceps skinfold measurement and 55% were below the 10th percentile. No biochemical abnormalities were noted. Breath [H2] tests: lactulose: all patients in both groups responded with positive tests. No difference in transit time was noted. Lactose: 73% of CHD had positive test compared to 36% control. Sorbitol: 73% of CHD had positive test compared to 27% control (p less than 0.05). Fructose: 27% CHD compared to 0% control. This study confirmed that CHD patients have decreased fat stores. It demonstrates for the first time that CHD patients have increased incidence of malabsorption of sorbitol. This carbohydrate malabsorption may contribute to the nutritional abnormalities of CHD.

Adult↗
PubMed1985

Protease nexin. Properties and a modified purification procedure.

The present paper describes chemical and functional properties of protease nexin, a serine protease inhibitor released from cultured human fibroblasts. It is shown that protease nexin is actually synthesized by fibroblasts and represents about 1% of their secreted protein. Analysis of the amino acid composition of purified protease nexin indicates that it is evolutionarily related to antithrombin III and heparin cofactor II. Protease nexin contains approximately 6% carbohydrate, with 2.3% amino sugar, 1.1% neutral sugar, and 3.0% sialic acid. The Mr calculated from equilibrium sedimentation analysis is 43,000. Protease nexin is a broad specificity inhibitor of trypsin-like serine proteases. It reacts rapidly with trypsin (kassoc = 4.2 +/- 0.4 X 10(6) M-1 s-1), thrombin (kassoc = 6.0 +/- 1.3 X 10(5) M-1 s-1), urokinase (kassoc = 1.5 +/- 0.1 X 10(5) M-1 s-1), and plasmin (kassoc = 1.3 +/- 0.1 X 10(5) M-1 s-1), and slowly inhibits Factor Xa and the gamma subunit of nerve growth factor but does not inhibit chymotrypsin-like proteases or leukocyte elastase. In the presence of heparin, protease nexin inhibits thrombin at a nearly diffusion-controlled rate. Two heparin affinity classes of protease nexin can be detected. The present characterization pertains to the fraction of protease nexin having the higher affinity for heparin. The low affinity material, which is the minor fraction, is lost during purification.

Amino Acids↗
PubMed1985

Nuclear chromatin decondensation of spermatozoa in vitro: a method for evaluating the fertilizing ability of ovine semen.

Spermatozoa obtained from testes, epididimydes and complete ejaculates of healthy rams during the breeding and non-breeding seasons were induced to show nuclear chromatin decondensation by controlled exposure to dithiotreitol (DTT) and sodium dodecyl sulphate (SDS) in vitro. A gradual resistance to decondensation was shown by sperm during epididymal transit, confirming a progressive increase in the prevalence of chromatinic disulphide bonds during sperm maturation in this species. A high % of stable (non-decondensed) sperm nuclei after treatment (79%) was found in semen from rams with normal fertility (64% non-return rate at first oestrus). Opposite changes were found in the semen from rams having low fertility rates (37%), as these showed only 31% of stable sperm nuclei. There were no differences in the spermiograms of these two groups. When semen from the same rams was tested during the non-breeding season, a similar relationship was found, although in both groups there was a higher % of sperm with stable nuclei than during the breeding season. The possible role of seminal plasma and of some of its constituents (e.g., zinc) on the decondensation of ram sperm nuclear chromatin was also studied. The presence of seminal plasma and the addition of zinc largely or completely inhibited the decondensation of ram sperm nuclear chromatin whilst the reverse situation was seen following the addition of chelating agents (e.g. EDTA) to the semen samples. The present results suggest that the induction of sperm nuclear decondensation by exposure to DTT and SDS under controlled conditions may provide a simple but reliable method for predicting in vitro the fertilizing ability of a ram semen sample.

Animals↗
PubMed1985

Case-control study to identify risk factors for paediatric endemic typhoid fever in Santiago, Chile.

Typhoid fever is an important endemic health problem in Santiago, Chile. Its incidence has more than doubled in recent years, during which access to potable water and sewage disposal in the home became almost universal in the city. A matched case-control study was carried out to identify risk factors and vehicles of transmission of paediatric typhoid fever; 81 children in the 3-14-years age group with typhoid fever were compared with controls, matched with respect to age, sex, and neighbourhood. It was found that case children more frequently bought lunch at school and shared food with classmates. Also, case children more often consumed flavoured ices bought outside the home; none of 41 other food items considered in the study was associated with a higher risk of typhoid fever. Only two food handlers for cases and one for controls were positive for Salmonella typhi, indicating that persons preparing food solely for their own family were not the main source of S. typhi infection. Rather, the risk factors identified in this study are consistent with the hypothesis that paediatric endemic typhoid fever in Santiago is largely spread by consumption of food-stuffs that are prepared outside the individual's home and are shared with or sold to children.

Adolescent↗
PubMed1984

Design and operation of a completely automated Beckman microsequencer.

A unique, efficient, and inexpensive system has been designed and built for the automatic conversion of anilinothiazolinone derivatives extracted from a Beckman spinning-cup sequencer with subsequent on-line high-pressure liquid chromatography separation of the phenylthiohydantoin derivatives. The Auto Converter-Auto Sampler system is controlled by a tape programmer or microprocessor and operates by transfer of the sample from the conversion vial into an HPLC injection loop by nitrogen pressure. Incorporation of a minor programming change on the sequencer allows the introduction of nitrogen vapor into the spinning cup during phenylisothiocyanate coupling. These modifications have resulted in a completely automated subnanomole protein sequencer.

Amino Acid Sequence↗
PubMed1984

Natural human interferon-gamma. Complete amino acid sequence and determination of sites of glycosylation.

Fresh human peripheral blood lymphocytes were induced with desacetylthymosin -alpha 1 and staphylococcal enterotoxin B. The induced gamma interferon (or IFN-gamma, immune interferon, type II interferon) was purified to homogeneity utilizing controlled-pore glass, concanavalin A-Sepharose, Bio-Gel P100, or Sephacryl S-200, and reversed phase high performance liquid chromatography. This procedure resulted in two active species with apparent Mr = 20,000 and 25,000 as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Both species were found to have identical amino acid sequences with a pyroglutamate residue as NH2-terminus. In both cases six different COOH termini were found. They are, at least qualitatively, identical in both species. There are two possible Asn-X-Ser/Thr glycosylation sites. Both carry carbohydrates in the Mr = 25,000 species whereas in the Mr = 20,000 species only one site is glycosylated. This likely explains the difference in apparent molecular weight between the two species and the expected molecular weight based upon the amino acid sequence.

Amino Acid Sequence↗
PubMed1984

Typhoid fever in Santiago, Chile: a study of household contacts of pediatric patients.

We obtained clinical, epidemiological, and laboratory data (including three stool cultures) from 155 (96%) of 161 household contacts of 24 patients less than 16 years old with culture-confirmed typhoid fever; these 24 patients represented approximately 40% of such patients seen in three hospitals in Santiago during a 12-week period. A chronic typhoid carrier was identified in only one household, with concurrent or secondary cases seen in two other households. When index cases were matched with household members nearest in age, no specific risk factors for illness could be identified. There was evidence of generalized exposure to enteric pathogens within these households, with nine persons from seven different households culture-positive for non-typhoidal Salmonella, and nine, from eight different households, culture-positive for Shigella; transmission of these pathogens within households did not appear to be common since no household had more than one family member with the same serotype or species of either pathogen.

Adolescent↗
PubMed1983

A discontinuous electrophoretic system for separating peptides on polyacrylamide gels.

An electrophoretic system for separating, with high resolution, peptides 25-250 residues in length is described. The peptides are stacked by discontinuous electrophoresis to form very sharp bands at the origin. They are then separated on a matrix of 20% polyacrylamide, 8 M urea, and 0.1% dodecyl sulfate. Through this combination, high resolution and clean separation, based on polymer length, are achieved.

Animals↗
PubMed1983

Development of selected neurological skills.

The development of several selected neurological skills in 592 children, ages 3 to 6 years 11 months, were studied. The sequence in the development of these skills included the ability to point up and down, to keep the arms extended, pointing back, to open and close a safety pin, pointing front, figure identification, single finger identification, and right-left concept developing shortly after the others. Clinical implications of these findings have not been evaluated in this study.

Brain Damage, Chronic↗
PubMed1979

Studies on the contractile activity and ultrastructure of the boar testicular capsule.

The ultrastructure and the spontaneous and drug-induced contractility of the testicular capsule of 18 boars were investigated. Isometric recordings were obtained in vitro using strips of the tunica albuginea isolated from various regions of the testis. Maximal contractile activity was found in the strips of the posterior border of the testis, in which the histological studies (light and electron microscopy) showed abundant typical smooth muscle cells distributed in layers parallel to the testicular long axis. These cells were largely aggregated in the inner layer of the testicular capsule, which displayed contractile activity similar to that of the entire tunica albuginea. The outer layer of the tunica albuginea was almost totally devoid of smooth muscle fibres and showed little or no contractility. The spontaneous contractions were rhythmic and exhibited an amplitude of 20--70 mg and a frequency of 5--30 contractions/10 min. Norepinephrine, acetylcholine and oxytocin all produced an increase of the contractility of the tunica albuginea, consisting mainly in a rise of the tone.

Acetylcholine↗
PubMed1976

[Miconazole per os in tinea and deep mycosis].

For the last 6 years we have been using Miconazole cream in the treatment of tinea and vaginal candidiasis. We think that it is at least as good as the best drugs for this purpose, but consider it difficult to decide about its superiority. Therefore we refrain from describing this part of our experience in detail. We have employed Miconazole "per os" at the daily doses of 24-28 mg./kg. in treating 3 cases of tinea corporis or cruris by "Trichophyton rubrum". Symptoms ceased in 3 days; mycologic examination turned negative in 2 weeks; treatment ended in apparent cure in 3 weeks. We have employed Miconazole "per venam" and "per os" in the treatment of: mycetomata (2) by "Streptomyces somaliensis", without success; mycetoma by "Madurella grisea" (1), without success; chromomycosis by a 5-flucytosine resistant strain of "Cladosporium carrionii" (1), without success; paracoccidioidosis (5) with lesions in mouth and lungs, with good results; leishmaniasis by "Leishmania brasiliensis" (1), without success; mucocutaneous disseminated candidiasis (1), with very good results. Tolerance has been excellent: but pruritus appeared from the third week with 600 or more mg. "per venam", in several patients. Doses varied between 10 and 50 mg./kg./day. One patient, who suffered with candidiasis, is taking 50 to 30 mg./kg./day since more than a year ago and, being a child, he is feeling well and growing to be normal. We recommend employing Miconazole against systemic canidiasis, sulpharesistant paracoccidioidosis and assaying it further in tinea (at least, in griseofulvin-resistant cases).

Administration, Oral↗