Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 224
Filtrar
1.
Int J Legal Med ; 137(5): 1463-1469, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37410175

RESUMEN

In contrast to gunshot wounds in skin and bone, the medico-legal literature pays little attention to the appearance of bullet penetration sites in abdominal organs. It was only in 1983 that Metter and Schulz published an article entitled "Morphological features of gunshot wounds in the liver and spleen." According to their observations, the organs in question showed stellate tears at the bullet penetration sites resembling skin wounds from contact shots to body regions having a bony support. The study presented simulated the real conditions by means of test shots to composite models consisting of porcine organs embedded in ballistic gelatin. The ammunition used was pistol cartridges 9 mm Luger with full metal jacket round nose bullets. The shots were video-documented with a high-speed camera in order to record the bullet's travel through the target. In addition, the composite models fired at underwent CT examinations followed by a macroscopic assessment of the organs. The study confirmed the findings of Metter and Schulz with regard to the star-like appearance of gunshot wounds in the liver and spleen. Likewise, the kidney showed radiating tears originating from the bullet path, whereas the wound track in pulmonary tissue was tube-shaped and lacked additional cracks. The varying wound patterns in parenchymatous organs can reasonably be explained as a consequence of the respective viscoelastic tissue properties.


Asunto(s)
Armas de Fuego , Heridas por Arma de Fuego , Animales , Porcinos , Balística Forense , Piel/lesiones , Hígado/lesiones
2.
Int J Legal Med ; 136(6): 1597-1603, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36006518

RESUMEN

The aim of the present study was to establish whether the size (diameter and area) of bullet entrance holes in skin varies between distant shots to the anterior and posterior trunk, respectively, when using the same ammunition (in concreto pistol cartridges 9 mm Luger). For that purpose, specimens of porcine skin from the belly region and the back were taken (10 samples each) and shot at from a distance of 1.6 m. The entrance holes were photo-documented under standardised conditions. After image processing for contrast enhancement, the maximum diameter and the area of each skin defect were measured automatically by means of an image analysis system. Both size parameters differed significantly depending on the body region affected. On the back with its comparatively thick dermis, the skin defects were considerably smaller than those on the ventral trunk where the corium is less thick. This difference can be explained by the fact that the elastic properties of skin are strongly determined by the connective tissue which is especially rich in fibres. The study results were consistent with the authors' casework experience and support the assumption that the entrance site of gunshot wounds has a major influence on the size of the bullet hole in skin.


Asunto(s)
Armas de Fuego , Heridas por Arma de Fuego , Animales , Balística Forense/métodos , Piel/lesiones , Porcinos
3.
Int J Legal Med ; 123(5): 419-25, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19636582

RESUMEN

A bullet that has passed in and out of one body segment may continue its way into another part of the body causing a second entrance ("reentry") wound, which is often said to have an atypical and sometimes confusing appearance. To analyze this problem in a systematical approach, 9-mm Parabellum full metal-jacketed projectiles were fired at skin-gelatine composite models simulating the consecutive passage of a bullet through two parts of a body. When there was a distance between the two segments, the primary exit and the reentry skin wounds did not show any distinctive features differing from usual gunshot injuries. In the case of contact between exit and reentry site, the corresponding skin wounds resembled each other as both had central tissue defects surrounded by abrasion areas. The subsequent investigation of the simulant revealed that skin particles from both the exit and the adjacent reentry site had been displaced in the direction of the shot along the whole bullet track of the second segment. The morphological findings are presented and discussed with respect to the pertinent literature, and possible physical ballistic explanations are suggested.


Asunto(s)
Balística Forense , Modelos Anatómicos , Heridas por Arma de Fuego/patología , Animales , Gelatina , Humanos , Piel , Porcinos , Grabación en Video
4.
Forensic Sci Int ; 165(2-3): 144-9, 2007 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-16822631

RESUMEN

Medical criminalistics is an essential part of legal/forensic medicine. It includes the clinical examination of surviving victims and suspects, the inspection of the scene in suspicious deaths with subsequent performance of medico-legal autopsies, the assessment of (biological) traces and the reconstruction of criminal events under medical aspects. Just as the circumstances of life and the manifestations of crime are changing with time, there is a permanent alteration regarding the issues of medical criminalistics. Legal/forensic medicine is a university subject in most countries and therefore, research work is one of the main tasks also in medical criminalistics. In contrast to clinical medicine and basic research, some common study designs are not suitable for the special needs of medical criminalistics, whereas other types are more appropriate like epidemiological evaluations, cross-sectional studies and (retrospective) observation studies. Moreover, experimental model tests and case reports also rate high in medical criminalistics.


Asunto(s)
Medicina Legal/métodos , Edición , Proyectos de Investigación , Ética en Investigación , Humanos , Control de Calidad
5.
Forensic Sci Int ; 159(2-3): 226-9, 2006 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-16271289

RESUMEN

The report deals with two adolescents (a 17-year-old Turkish boy and a 15-year-old German girl) who simulated right-wing assaults by cutting National Socialist symbols into their own skin. The fact that Nazi symbols were chosen was obviously due to the idea that the alleged commission of the offense by right-wingers would not be doubted due to the negative image of this group. The alleged victims did not inform the police until the family or close friends urged them to report the incident. The rapid elucidation of the facts was possible because medicolegal experts were called in at an early stage of the investigations. The injuries showed typical morphological features of self-infliction (localization in easily accessible parts of the body, multitude of singular lesions with a linear or slightly curved course, equally shallow and non-penetrating cuts, arrangement in groups or over a defined area, lack of defense injuries, no corresponding damage to the clothing).


Asunto(s)
Automutilación/diagnóstico , Simbolismo , Adolescente , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Nacionalsocialismo , Política , Automutilación/patología
6.
Forensic Sci Int ; 158(2-3): 195-9, 2006 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-16169176

RESUMEN

Munchausen syndrome by proxy is a subtle and difficult to diagnose form of child abuse in which the carer (usually the mother) simulates, manipulates or produces symptoms of illness in the victim. In most cases the detrimental effect is caused by applying foreign substances or by airway obstruction. In the presented case a 20-month-old girl developed a spreading soft-tissue infection resistant to treatment on the left upper arm after vaccination, which required a number of surgical interventions. Repeatedly, microorganisms from the intestinal flora were isolated from the wound secretion. After the girl suffered respiratory and circulatory arrest, which required resuscitation measures, chemical toxicological tests revealed not medically prescribed benzodiazepines in serum and urine. When the mother, a trained nurse, was confronted with the allegation to have manipulated the symptoms of the illness she committed suicide. The forensic autopsy of the suicide produced numerous hints suggesting chronic self-damaging behaviour described as Munchausen syndrome. This case shows a number of manipulation forms with the maintenance of a chronic skin and soft tissue infection belonging to the rarer forms of inflicting damage to the child. It also illustrates that confrontation with the allegation of Munchausen syndrome by proxy creates a very stressful emotional situation that may lead to a suicidal act.


Asunto(s)
Madres/psicología , Síndrome de Munchausen Causado por Tercero/psicología , Suicidio , Enfermedad Crónica , Farmacorresistencia Bacteriana , Femenino , Medicina Legal , Humanos , Lactante , Síndrome de Munchausen Causado por Tercero/diagnóstico , Infecciones de los Tejidos Blandos/patología , Infecciones de los Tejidos Blandos/terapia , Colgajos Quirúrgicos , Heridas Punzantes/patología
7.
Forensic Sci Int ; 263: 158-163, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27129143

RESUMEN

When skin is subjected to water temperatures gradually rising from moderate to critical ranges for a prolonged period of time, the resulting scalds will initially present as reddening, followed by blistering and at last by full-thickness burns. On changing from second- to third-degree burn, the blisters stop to become enlarged and solidify due to heat-induced coagulation necrosis. Such gradually intensifying tissue damage results in multiple firm skin blisters together with third-degree burn of the affected area. The initially serous blister fluid assumes a jelly-like consistency as the proteins undergo denaturation. Scalds of this special type may occur in persons taking a bath and becoming incapable to act so that the warm water tap remains turned on or a hairdryer continues to work after having been dropped into the bath water. On the basis of two relevant fatalities (suicidal electrocutions in bathtubs by means of hairdryers), the macroscopic and histological appearance of blisters which only secondarily turned into a full-thickness scald is compared with blisters in genuine second-degree scalds. The blister fluid of the latter ones was also investigated as to their protein composition and hemoglobin concentration.


Asunto(s)
Baños , Vesícula/metabolismo , Vesícula/patología , Quemaduras/patología , Calor/efectos adversos , Traumatismos por Electricidad/complicaciones , Femenino , Patologia Forense , Hemoglobinas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Derrame Pleural/metabolismo , Proteínas/metabolismo
8.
J Am Coll Cardiol ; 7(5): 1167-73, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3958375

RESUMEN

A valve ring abscess was diagnosed in four patients with a prosthetic aortic valve by identifying an echo-free space on two-dimensional echocardiography. Three of the patients presented with severe aortic regurgitation and congestive heart failure after an episode of endocarditis, but two of them did not have evidence of active endocarditis. The fourth patient had endocarditis, but no evidence of aortic regurgitation or heart failure. All four patients required valve replacement. Similar findings in all 11 previously reported cases suggest that a valve ring abscess can be diagnosed by two-dimensional echocardiography. It may be found without clinical evidence of endocarditis, in the absence of aortic regurgitation, without echocardiographically identifiable vegetations or during resolution of endocarditis.


Asunto(s)
Absceso/diagnóstico , Válvula Aórtica , Prótesis e Implantes , Absceso/etiología , Adulto , Ecocardiografía , Endocarditis/complicaciones , Endocarditis/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
J Am Coll Cardiol ; 11(1): 89-93, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2961794

RESUMEN

Echocardiographic color Doppler flow mapping was performed in 46 normal women to determine the normal flow phenomena across each of the four heart valves. Three groups were studied: Group I consisted of 15 highly trained long distance runners, mean age 27 years, running an average of 105 km/week, with a mean rest heart rate of 45 beats/min; Group II consisted of 14 moderately trained long distance runners, mean age 28, running an average of 60 km/week, with a mean rest heart rate of 53 beats/min; Group III consisted of 17 sedentary control subjects, mean age 28, with a mean rest heart rate of 77 beats/min. Color Doppler flow mapping showed that the ventricular inflow and outflow patterns were the same for each of the groups and identified a regurgitant flow pattern across each of the valves. A tricuspid regurgitant flow pattern was present in 14 subjects (93%) in Group I, 8 (57%) in Group II and 4 (24%) in Group III. A pulmonary regurgitant flow pattern was present in 13 subjects (87%) in Group I, 8 (57%) in Group II and 3 (18%) in Group III. A mitral regurgitant flow pattern was present in 4 subjects (20%) in Group I, 5 (35%) in Group II and 1 (17%) in Group III and an aortic regurgitant flow pattern was present in 1 subject (6%) in Group I. Patients in Group I had significantly more tricuspid and pulmonary regurgitant flow patterns than did patients in Group III (p less than 0.001). Heart rate and distance training in women appear to correlate with the frequency of tricuspid and pulmonary regurgitant flow patterns.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Circulación Coronaria , Ecocardiografía/métodos , Corazón/fisiología , Carrera , Adulto , Color , Femenino , Frecuencia Cardíaca , Humanos , Insuficiencia de la Válvula Mitral/diagnóstico , Educación y Entrenamiento Físico , Insuficiencia de la Válvula Pulmonar/diagnóstico , Reología , Insuficiencia de la Válvula Tricúspide/diagnóstico
10.
Clin Exp Med ; 5(2): 80-5, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16096858

RESUMEN

Autoantibodies against bactericidal/permeability-increasing protein (BPI-ANCA) were found in patients with cystic fibrosis (CF). It is speculated that they represent a marker of the chronic endobronchial infection and sustained inflammatory response in CF. Our aim was to evaluate whether azithromycin (AZM), through its antiinflammatory effect, could affect the level of BPI-ANCA in CF patients. Eighteen patients with CF aged 5.5-36.3 years (median 15.1) were enrolled in a randomised, double-blind, placebo-controlled trial of AZM (250 mg twice a week to 10 patients) or placebo (8 patients) for 12 weeks. BPI-ANCA levels were recorded pre- and post-treatment and compared to a group of 18 matched healthy controls. Chi-square analysis, Kruskal-Wallis and Mann-Whitney tests were used to compare between the groups. Pre- and post-treatment values were compared using the Wilcoxon Signed-Ranked test. BPI-ANCA was found in 12 CF patients (67%) and four (22%) healthy subjects (P<0.001). The mean BPI-ANCA level was 3.94+/-6.15 U/ml (mean+/-SD) in healthy subjects and 38.11+/-42.34 U/ml in CF patients (P=0.023). The mean BPI-ANCA level was higher in patients with Pseudomonas aeruginosa compared to those without (64+/-35 U/ml and 25+/-41 U/ml respectively, P=0.032). No change in BPI-ANCA levels occurred in the AZM-treated patients [35 (0-127) U/ml (median (range) and 30 (0-120) U/ml, respectively] or in the placebo group [10 (0-66) U/ml and 13 (0-83) U/ml, respectively]. BPI-ANCA levels are significantly higher in patients with CF compared to healthy controls. BPIANCA levels are higher among patients colonised with P. aeruginosa. Twelve weeks of AZM therapy did not lower the BPI-ANCA level in patients with CF.


Asunto(s)
Antibacterianos/uso terapéutico , Autoanticuerpos/sangre , Azitromicina/uso terapéutico , Proteínas Sanguíneas/inmunología , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/inmunología , Proteínas de la Membrana/inmunología , Adolescente , Adulto , Péptidos Catiónicos Antimicrobianos , Niño , Femenino , Humanos , Masculino , Placebos
11.
Forensic Sci Int ; 149(1): 75-9, 2005 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-15734113

RESUMEN

In a suicidal shot to the temple two roundish zones of powder soot blackening were found above the entrance wound. The paired zones of powder soot blackening were caused by two gas outlets located on the upper side of the muzzle end of the weapon used (converted blank cartridge pistol of make Rhöner). The conclusions that can be drawn from this particular soot pattern with regard to the type of the weapon, the muzzle-to-target distance, the direction of fire and the way of holding the weapon are discussed.


Asunto(s)
Balística Forense , Traumatismos Penetrantes de la Cabeza/patología , Suicidio , Heridas por Arma de Fuego/patología , Humanos , Masculino , Persona de Mediana Edad
12.
Arch Intern Med ; 143(4): 837-8, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6340632

RESUMEN

Vibrio vulnificus was isolated from blood and stool cultures from a 65-year-old man who had underlying alcoholic liver disease. The patient had eaten raw oysters the day before he became ill. To our knowledge, this is the first published report of isolation of the organism from stool in a patient with primary septicemia, and it provides support for epidemiologic studies suggesting that the infection is acquired through the gastrointestinal tract by eating raw seafood containing the organism. It was also possible, in this case, to demonstrate the presence of high antibody titers to the blood isolate by indirect immunofluorescence but not by agglutinating or vibriocidal tests.


Asunto(s)
Heces/microbiología , Sepsis/etiología , Vibriosis/sangre , Vibrio/aislamiento & purificación , Anciano , Anticuerpos Antibacterianos/análisis , Técnica del Anticuerpo Fluorescente , Enfermedades Transmitidas por los Alimentos/sangre , Enfermedades Transmitidas por los Alimentos/etiología , Enfermedades Transmitidas por los Alimentos/inmunología , Humanos , Cirrosis Hepática Alcohólica/complicaciones , Masculino , Ostreidae/microbiología , Vibrio/inmunología , Vibriosis/complicaciones , Vibriosis/inmunología
13.
Mol Immunol ; 23(1): 1-13, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3083239

RESUMEN

Membrane immunoglobulin receptors on chicken B-cells have been shown to display a heterogeneity with respect to interchain disulfide linkages. One fraction of the surface Ig (sIg) appears to display the traditional H2-L2 linkage. We also present evidence that this Ig is covalently bound via a disulfide linkage to actin. In this instance, the isolated Ig heavy chain, after reduction, has a mol. wt of 80 K. Perhaps more significantly, we show that another fraction of the sIg exists in a highly aggregated from that is stabilized by disulfide linkages. In contrast to the sIg found in the H2-L2 configuration, there is no evidence of actin within the aggregates and the sIg heavy chains isolated from these aggregates display a slightly faster mobility on SDS-PAGE under reducing conditions, running at about 77K. Furthermore, it appears that the Ig within the large aggregates may have a higher avidity with respect to antigen binding, and so this Ig structure may be the more relevant to antigen-induced receptor-mediated signaling in the B-cell.


Asunto(s)
Linfocitos B/inmunología , Disulfuros/metabolismo , Receptores de Antígenos de Linfocitos B/metabolismo , Animales , Pollos , Cromatografía de Afinidad , Electroforesis en Gel de Poliacrilamida , Cadenas Pesadas de Inmunoglobulina/análisis , Peso Molecular , Bazo/inmunología
14.
Mol Immunol ; 23(2): 97-109, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2939336

RESUMEN

Antigen-specific receptors of B- or T-cells were selectively radiolabeled among the spleen cells from either human gammaglobulin immunized normal or bursectomized agammaglobulinemic chickens. Selective in situ radioiodination was accomplished by employing lactoperoxidase (LPO) covalently linked to antigen (Ag). Ag-specific receptors on B- or T-cells were allowed to bind Ag-LPO conjugates via the Ag portion of the conjugates and then to be selectively catalyzed for iodination by the LPO portion of the bound Ag-LPO conjugates. Radioiodinated cells were either processed for autoradiography to detect Ag-binding cells directly under the microscope or solubilized with detergents for protein analysis with two-dimensional (2-D) gel electrophoresis. On a cellular level, Ag-binding B- and T-cells were selectively radiolabeled and clearly visualized via autoradiography. On a molecular level, selectively radiolabeled Ag-specific membrane immunoglobulin of B-cells was demonstrated on 2-D gel autoradiographs. Furthermore, a unique polypeptide of Ag-specific T-cells with a reduced apparent mol. wt of 27 K and an apparent pI of 5.5-5.7 was demonstrated on 2-D gel autoradiograms. The 27 K molecule appears to be a T-cell receptor component itself, or a closely associated molecule.


Asunto(s)
Receptores de Antígenos de Linfocitos T/análisis , Linfocitos T Reguladores/inmunología , Animales , Linfocitos B/inmunología , Pollos , Electroforesis en Gel de Poliacrilamida , Radioisótopos de Yodo , Focalización Isoeléctrica , Lactoperoxidasa , Péptidos/análisis , Receptores de Antígenos de Linfocitos B/análisis
15.
Forensic Sci Int ; 257: 341-346, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26490008

RESUMEN

Pistols, revolvers and blank guns are not only used to discharge cartridges, but also for hits to the victim. In such cases, the blows preferably affect the head and/or the interposed hands protecting the body. The impact is mostly exerted either by the grip of a pistol or the butt of a revolver. In vigorous thrusts inflicted with the muzzle end of the weapon, the edge of the barrel may produce circular punch lesions with central skin flaps roughly corresponding to the bore. As in other kinds of pistol-whipping, the scalp wounds may be associated with fractures of the skull and even with brain contusions. Using the example of a homicide committed by pistol-whipping, the morphological features of blunt injuries from a handgun's muzzle are presented. The characteristic wound pattern found on the victim's head could be reproduced experimentally by forceful blows to the forehead of a slaughtered pig. In the case presented, the dominant hand of the perpetrator showed friction blisters due to prolonged striking with an unhandy tool in the form of a pistol.


Asunto(s)
Traumatismos Faciales/patología , Armas de Fuego , Frente/lesiones , Laceraciones/patología , Cuero Cabelludo/lesiones , Animales , Lesiones Encefálicas/etiología , Lesiones Encefálicas/patología , Traumatismos Faciales/etiología , Patologia Forense , Humanos , Laceraciones/etiología , Masculino , Modelos Animales , Porcinos , Adulto Joven
16.
Forensic Sci Int ; 257: e1-e5, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26296471

RESUMEN

Acute subdural hematomas are mostly due to blunt traumatization of the head. In rare instances, subdural bleeding occurs without evidence of a previous trauma following spontaneous hemorrhage, e.g. from a ruptured aneurysm or an intracerebral hematoma perforating the brain surface and the arachnoid. The paper presents the morphological, microbiological and toxicological findings in a 38-year-old drug addict who was found by his partner in a dazed state. When brought to a hospital, he underwent trepanation to empty a right-sided subdural hematoma, but he died already 4h after admission. Autopsy revealed previously undiagnosed infective endocarditis of the aortic valve as well as multiple infarctions of brain, spleen and kidneys obviously caused by septic emboli. The subdural hematoma originated from a subcortical brain hemorrhage which had perforated into the subdural space. Microbiological investigation of the polypous vegetations adhering to the aortic valve revealed colonization by Streptococcus mitis and Klebsiella oxytoca. According to the toxicological analysis, no psychotropic substances had contributed to the lethal outcome. The case reported underlines that all deaths of drug addicts should be subjected to complete forensic autopsy, as apart from intoxications also natural and traumatic causes of death have to be taken into consideration.


Asunto(s)
Consumidores de Drogas , Endocarditis Bacteriana/patología , Hematoma Subdural Agudo/patología , Embolia Intracraneal/microbiología , Embolia Intracraneal/patología , Adulto , Válvula Aórtica/microbiología , Válvula Aórtica/patología , Infarto Encefálico/etiología , Infarto Encefálico/patología , Endocarditis Bacteriana/complicaciones , Resultado Fatal , Hematoma Subdural Agudo/etiología , Humanos , Infarto/etiología , Infarto/patología , Embolia Intracraneal/complicaciones , Hemorragias Intracraneales/complicaciones , Hemorragias Intracraneales/patología , Riñón/irrigación sanguínea , Riñón/patología , Infecciones por Klebsiella/complicaciones , Klebsiella oxytoca/aislamiento & purificación , Masculino , Infarto del Bazo/etiología , Infarto del Bazo/patología , Infecciones Estreptocócicas/complicaciones , Streptococcus mitis/aislamiento & purificación
17.
Forensic Sci Int ; 249: 42-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25659117

RESUMEN

A traffic accident victim run over by a vehicle may show a patterned skin hematoma reflecting the grooves of the tire's profile. Apart from this well-known type of imprint mark, the affected skin can also be blistered provided that the wheel exerts high pressure on the body for a prolonged period of time. The macro- and micromorphological findings as well as the protein composition of the blister fluid were investigated on the basis of a relevant autopsy case. Analogous to blisters associated with hanging marks, the transudation of serous fluid with consecutive detachment of the epidermis is interpreted as a pressure-related effect which cannot be regarded as a sign of vitality.


Asunto(s)
Accidentes de Tránsito , Vesícula/diagnóstico , Vesícula/etiología , Hematoma/diagnóstico , Hematoma/etiología , Heridas no Penetrantes/complicaciones , Autopsia , Ciclismo , Niño , Resultado Fatal , Femenino , Humanos , Piel
18.
Endocrinology ; 126(1): 199-208, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2293984

RESUMEN

To characterize the structures of the various forms of hCG and its immunologically related fragments measured in blood, urine, and tissue culture media, we developed a highly sensitive HPLC tryptic fingerprinting system that can characterize as little as 15 micrograms of material. Standard preparations of the subunits of hCG purified from pregnancy urine were found to exhibit heterogeneity on reverse phase HPLC chromatography, complicating efforts to characterize such forms of hCG. The same type of chromatographic heterogeneity was observed when the hormone was reduced and S-carboxymethylated (RCM) and its RCM subunits separated on HPLC. One major and one minor peak were observed in the alpha- and beta-subunits from both native and RCM hormone, with a ratio of between 5:1 and 10:1. Development and application of a high resolution, semimicrobore HPLC fingerprint technique used together with an examination of selected peptides by amino acid sequencing and mass spectrometry defined the differences between these forms as oxidation. Using each of the isolated RCM subunit's major and minor HPLC peaks, the oxidation was shown to be reversible and probably due to interconversion of methionine with its sulfoxide form.


Asunto(s)
Gonadotropina Coriónica , Cromatografía Líquida de Alta Presión/métodos , Mapeo Peptídico/métodos , Gonadotropina Coriónica/metabolismo , Cromatografía en Gel , Humanos , Espectrometría de Masas , Oxidación-Reducción , Tripsina
19.
Endocrinology ; 138(3): 1232-9, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9048631

RESUMEN

We have expressed the extracellular binding domain of the human LH/CG receptor as a fusion with the cpIII filamentous phage coat protein. These fusion phage are able to specifically bind ELISA plates coated with hCG. Preincubation of the phage with hCG before exposure to the coated plates inhibited binding of phage, whereas human FSH had no effect. Furthermore, addition of anti-hLH/CG receptor antisera inhibited binding of phage to the plates. We have also tested the effect of monoclonal antibodies to hCG on phage binding. Monoclonal antibodies that can bind hCG when it is bound to native receptor do not inhibit phage binding. These include B105 and A109 Alternatively, B107 and B109 have an inhibitory effect on phage binding. They cannot bind hCG when it is bound to receptor and are likely directed against epitopes at or near the receptor binding interface. Therefore, these fusion phage exhibit the same binding specificity as the wild-type receptor and likely display the extracellular domain of the hLH/CG receptor on their surface in the native conformation. Phage display is a potentially useful tool for studying the hLH/CG receptor structure and in screening for synthetic compounds that compete with hormone for receptor binding.


Asunto(s)
Bacteriófagos/metabolismo , Gonadotropina Coriónica/metabolismo , Receptores de HL/genética , Receptores de HL/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Unión Competitiva , Ensayo de Inmunoadsorción Enzimática , Humanos , Sueros Inmunes/inmunología , Datos de Secuencia Molecular , Receptores de HL/inmunología , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , Recombinación Genética
20.
Endocrinology ; 133(3): 1390-7, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7689955

RESUMEN

hCG is found in pregnancy urine and in urine from some cancer patients in a variety of forms whose concentrations have clinical importance. Recently, concerns about accurate measurement of these forms have been raised because of the finding that hCG with peptide bond cleavages within the beta-subunit is not recognized by commonly used antibodies. Such nicked forms of hCG are biologically inactive or of very low activity. They are present in normal pregnancy urine and to varying extents in the urine of patients with trophoblastic disease. International reference preparations of hCG contain nicked forms of hCG. Previously, it was not possible to separate nicked hormone from the intact form of hCG. This was a serious impediment to producing improved reference standards from natural pregnancy hormone. We now report that a simple hydrophobic purification scheme separates intact hCG from nicked hCG as well as from hCG beta core fragment. This scheme is a modification of the method of Hiyama et al. The order of elution from low to high hydrophobicity is hCG beta core fragment, nicked hCG, and lastly, intact hCG. Nicking of the putative amphipathic helix loop, hCG beta 38-57, apparently renders the hormone significantly less hydrophobic despite the equal molar content of sialic acid. The hCG CR 127 nicked preparation was only 10% as potent as the reference preparation in a heterodimer-directed assay. The nicked-depleted hCG CR 127 was 30% more potent in this assay. Improved hCG reference standards should display similar increases in immunopotency (20-30%) with most antiheterodimeric antibodies and similar increases in bio-potency assays. It should now be possible to make reference preparations of these forms of hCG directly from the raw urine of normal pregnant patients and those with trophoblastic disease.


Asunto(s)
Gonadotropina Coriónica/aislamiento & purificación , Gonadotropina Coriónica/orina , Fragmentos de Péptidos/orina , Secuencia de Aminoácidos , Western Blotting , Fraccionamiento Químico , Gonadotropina Coriónica/química , Gonadotropina Coriónica Humana de Subunidad beta , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Inmunoensayo/normas , Sustancias Macromoleculares , Datos de Secuencia Molecular , Ácido N-Acetilneuramínico , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Embarazo , Control de Calidad , Estándares de Referencia , Ácidos Siálicos/análisis , Neoplasias Trofoblásticas/orina , Neoplasias Uterinas/orina
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda