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1.
Pediatr Pathol Mol Med ; 20(2): 155-65, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12673839

RESUMO

Although the endocrine pancreas appears to play an important role in the pathophysiology of sickle cell disease, very little is known about the morphologic changes in this tissue. Our study was initiated to delineate the microscopic features of the endocrine pancreas in a large autopsy series of sickle cell hemoglobinopathies. From more than 650 cases archived at the Centralized Pathology Unit for Sickle Cell Disease (Mobile, AL), 224 autopsy cases were identified for review of clinical and gross autopsy findings and/or for microscopic studies, including histochemical stains (trichrome, reticulin, iron), and immunohistochemical stains (insulin, glucagon, somatostatin, and pancreatic polypeptide). The gross examinations were recorded as unremarkable in 65% of the autopsies. In childhood and adolescence (< or = 18 years), pancreas weights (50.76 +/- 5.16SE gm) were significantly greater (p < 0.0001) than age-matched controls (30.42 +/- 3.59SE gm). In adulthood, pancreas weights (108.34 +/- 5.29SE gm) were not significantly different from controls (110 gm). Microscopic findings included vascular congestion (48%), edema (65%), siderosis (31%), and nesidioblastosis (76%), which included islet cell dispersion (53%), hyperplasia (23%), and hypertrophy (25%). Analysis by age groups suggested that islet cell dispersion/hyperplasia persists unchanged, whereas diameters of compact islets tend to increase with age. These findings may be related to local tissue hypoxia and/or increased metabolic energy needs in sickle cell disease.


Assuntos
Anemia Falciforme/complicações , Pancreatopatias/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Anemia Falciforme/fisiopatologia , Biomarcadores , Contagem de Células , Hipóxia Celular , Criança , Pré-Escolar , Feminino , Fibrose , Glucagon/análise , Humanos , Hiperplasia , Lactente , Insulina/análise , Ferro/análise , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Pâncreas/química , Pâncreas/patologia , Pancreatopatias/metabolismo , Pancreatopatias/patologia , Polipeptídeo Pancreático/análise , Somatostatina/análise
2.
N Engl J Med ; 342(25): 1855-65, 2000 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-10861320

RESUMO

BACKGROUND: The acute chest syndrome is the leading cause of death among patients with sickle cell disease. Since its cause is largely unknown, therapy is supportive. Pilot studies with improved diagnostic techniques suggest that infection and fat embolism are underdiagnosed in patients with the syndrome. METHODS: In a 30-center study, we analyzed 671 episodes of the acute chest syndrome in 538 patients with sickle cell disease to determine the cause, outcome, and response to therapy. We evaluated a treatment protocol that included matched transfusions, bronchodilators, and bronchoscopy. Samples of blood and respiratory tract secretions were sent to central laboratories for antibody testing, culture, DNA testing, and histopathological analyses. RESULTS: Nearly half the patients were initially admitted for another reason, mainly pain. When the acute chest syndrome was diagnosed, patients had hypoxia, decreasing hemoglobin values, and progressive multilobar pneumonia. The mean length of hospitalization was 10.5 days. Thirteen percent of patients required mechanical ventilation, and 3 percent died. Patients who were 20 or more years of age had a more severe course than those who were younger. Neurologic events occurred in 11 percent of patients, among whom 46 percent had respiratory failure. Treatment with phenotypically matched transfusions improved oxygenation, with a 1 percent rate of alloimmunization. One fifth of the patients who were treated with bronchodilators had clinical improvement. Eighty-one percent of patients who required mechanical ventilation recovered. A specific cause of the acute chest syndrome was identified in 38 percent of all episodes and 70 percent of episodes with complete data. Among the specific causes were pulmonary fat embolism and 27 different infectious pathogens. Eighteen patients died, and the most common causes of death were pulmonary emboli and infectious bronchopneumonia. Infection was a contributing factor in 56 percent of the deaths. CONCLUSIONS: Among patients with sickle cell disease, the acute chest syndrome is commonly precipitated by fat embolism and infection, especially community-acquired pneumonia. Among older patients and those with neurologic symptoms, the syndrome often progresses to respiratory failure. Treatment with transfusions and bronchodilators improves oxygenation, and with aggressive treatment, most patients who have respiratory failure recover.


Assuntos
Anemia Falciforme/complicações , Pneumopatias/etiologia , Doença Aguda , Adolescente , Adulto , Transfusão de Sangue , Broncodilatadores/uso terapêutico , Dor no Peito/etiologia , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/complicações , Embolia Gordurosa/complicações , Feminino , Humanos , Infecções/complicações , Pneumopatias/terapia , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , Embolia Pulmonar/complicações , Respiração Artificial , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia
4.
Ann Clin Lab Sci ; 28(3): 144-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9646854

RESUMO

A case is reported of a previously healthy 52-year-old African American male who presented with acute onset of abdominal pain. Progressive increase in his abdominal symptoms led to an exploratory laparotomy; however, no pathology was discovered. Postoperatively, the patient became hypoxemic which progressed to diffuse infiltrates on chest x-ray, suggestive of adult respiratory distress syndrome. He had a rapidly fatal course. Autopsy showed bone marrow infarction, fat embolism, splenomegaly, and widespread congestion with sickle erythrocytes. Hemoglobin electrophoresis done postmortem showed hemoglobin (Hb) SC disease that was undiagnosed antemortem. To the best of our knowledge, it is unusual for Hb SC to be diagnosed postmortem in adults. This case suggests that sickle cell disorders should be ruled out in patients at risk for hemoglobinopathy in the presence of signs and symptoms compatible with the disease, irrespective of age.


Assuntos
Embolia Gordurosa/etiologia , Doença da Hemoglobina SC/diagnóstico , Medula Óssea/patologia , Embolia Gordurosa/diagnóstico , Embolia Gordurosa/patologia , Evolução Fatal , Doença da Hemoglobina SC/complicações , Doença da Hemoglobina SC/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Esplenomegalia
5.
Placenta ; 19(4): 295-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9639325

RESUMO

Most frequently, placental glycogen has been studied as an index of fetal nutrition. There are no published studies of placental glycogen as an index of fetal stress. In this study of 1573 samples from 71 placentae, glycogen levels in the placental disk, fetal membranes and umbilical cord of normal uncomplicated pregnancies were compared with those in complicated pregnancies. The complicated pregnancies included preterm delivery, hypertensive disorders, inadequate prenatal care, substance abuse, maternal fever or infection, obesity, diabetes mellitus, premature rupture of membranes, intrauterine growth retardation, sickle cell trait, and acute meconium staining of amniotic fluid at delivery. The data showed that the only significant differences were in the subgroup complicated by meconium-stained amniotic fluid in which the placental disks and umbilical cords had significantly lower (P=0.0006) glycogen levels. This finding suggests a relatively specific association. It is interesting to speculate that the passage of meconium with its vasoconstrictive effect increases utilization of local glycogen stores, decreases local glycogen reserves needed for the work of further vasoconstriction, and, in the event of subsequent acute stress, impairs vascular perfusion of tissues. In this way, meconium could predispose the infant to asphyxia.


Assuntos
Líquido Amniótico/metabolismo , Glicogênio/metabolismo , Mecônio/metabolismo , Placenta/metabolismo , Cordão Umbilical/metabolismo , Estudos de Casos e Controles , Membranas Extraembrionárias/metabolismo , Feminino , Hipóxia Fetal/etiologia , Feto/metabolismo , Humanos , Recém-Nascido , Masculino , Gravidez , Complicações na Gravidez/metabolismo , Vasoconstrição/fisiologia
6.
J Stroke Cerebrovasc Dis ; 7(1): 32-43, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-17895054

RESUMO

GOAL: To determine whether children with sickle cell disease (SCD), but without clinical evidence of cerebrovascular disease, have vasculopathy shown by quantitative magnetic resonance angiography (MRA). METHODS: In a retrospective review of MRA films, we compared 47 SCD patients with 49 control patients. Time-of-flight three-dimensional T1-weighted gradient-echo images were reconstructed, by maximum-intensity projection, to show the basilar artery in coronal view, and basilar volume was calculated from measurements made on films. Basilar volume was correlated with hematocrit and with results of cognitive testing. FINDINGS: Mean basilar artery volume was 74% larger in SCD patients than in controls (P<.001). If the upper limit of normal is defined as mean adult volume +2 SD (< or =427 mm(3)), 2% (1 of 43) of controls but 37% (17 of 46) of SCD patients exceed this value (chi(2)=19.0; P<.001). Basilar volume correlated inversely with hematocrit (r=-.60; P<.0001), with full-scale IQ (r=-.62; P<.005), and with freedom from distractability (r=-.61; P<.006) in SCD patients. Analysis of basilar artery tissue from a 5-year-old SCD patient showed that basilar dilatation can be associated with pathological changes typical of hypertension. CONCLUSIONS: Approximately 37% of a heterogenous group of pediatric SCD patients had ectasia of the basilar artery. Quantitative MRA is sensitive to subtle vasculopathy that can go undetected in the qualitative analysis more commonly done. Data suggest that there is a substantial elevation of arteriolar blood volume in pediatric SCD patients, and that such patients may share disease features in common with adult hypertension.

7.
Science ; 278(5339): 876-8, 1997 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-9346488

RESUMO

To create mice expressing exclusively human sickle hemoglobin (HbS), transgenic mice expressing human alpha-, gamma-, and betaS-globin were generated and bred with knockout mice that had deletions of the murine alpha- and beta-globin genes. These sickle cell mice have the major features (irreversibly sickled red cells, anemia, multiorgan pathology) found in humans with sickle cell disease and, as such, represent a useful in vivo system to accelerate the development of improved therapies for this common genetic disease.


Assuntos
Anemia Falciforme/genética , Anemia Falciforme/patologia , Animais , Modelos Animais de Doenças , Feminino , Globinas/genética , Hemoglobina Falciforme/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos
8.
J Pediatr Hematol Oncol ; 19(5): 455-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9329469

RESUMO

PURPOSE: The purpose of this report is to describe the clinical and pathologic features of a patient with acute thrombosis of both internal carotid arteries leading to death. METHODS: This is a case report of special interest because of extensive brain vessel pathologic examination. RESULTS: The analysis of this case showed that the brain had suffered massive infarction and cerebral edema. The internal carotid arteries (ICAs) were occluded by acute thrombus. The arterial wall of the left ICA, studied at its distal segment, showed a small amount of intimal hyperplasia which did not cause encroachment on the lumen. Immunohistochemical stains indicated that this lesion was formed by proliferative vascular smooth muscle rather than incremental thrombus formation. CONCLUSION: Acute thrombus formation can occur in the large cerebral arteries of children with sickle cell disease in the presence of only minimal intimal hyperplasia. The intimal hyperplasia which forms the sickle related vasculopathy seen on angiography or detected by Transcranial Doppler may be more related to stimulation of smooth muscle cells than dysregulation of thromboregulation at the endothelial surface. Implications for preventive treatment are discussed.


Assuntos
Anemia Falciforme/complicações , Trombose das Artérias Carótidas/etiologia , Trombose das Artérias Carótidas/patologia , Artéria Carótida Interna , Doença Aguda , Morte Encefálica , Trombose das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/patologia , Evolução Fatal , Humanos , Imuno-Histoquímica , Lactente , Masculino , Tomografia Computadorizada por Raios X
9.
Arch Pathol Lab Med ; 121(5): 449-76, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9167599

RESUMO

The Placental Pathology Practice Guideline Development Task Force, a multidisciplinary group, has prepared this guideline to assist those involved with placental examination. It provides recommendations related to indications and methods for placental examination as well as sample worksheets. An algorithm for the handling of placentas summarizes the recommendations of the guideline. A summary of specific findings of placental examination together with their pathogenesis and clinical associations is also provided. Recommendations related to reporting with sample reporting formats are included. The guideline is intended as an educational tool, and its use should be guided by the individual circumstances and care setting of specific cases.


Assuntos
Patologia Cirúrgica/métodos , Patologia Cirúrgica/normas , Placenta/patologia , Humanos , Prontuários Médicos/normas , Sociedades Médicas , Manejo de Espécimes/normas , Estados Unidos
10.
Pediatr Pathol Lab Med ; 16(4): 597-605, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9025857

RESUMO

Glycogen in the placenta and its appendages is important for fetal well-being. The precise location of the glycogen stores, however, is unknown. This study was initiated to quantitate glycogen levels at well-defined sampling sites in more than 641 samples from 10 uncomplicated pregnancies and to correlate these glycogen levels with clinical and morphological variables. By biochemical assay, glycogen levels were greatest in the midumbilical cord section (29.08 +/- 1.18 mg/g dry wt) and lowest in the amnionic membrane (2.31 +/- 0.08 mg/g dry wt). Within the placental disk, parenchymal glycogen levels were greatest near the cord insertion (9.31 +/- 2.68 mg/g dry wt) and lowest at the periphery (5.71 +/- 1.14 mg/g dry wt). The midumbilical cord glycogen level showed strong direct correlations (P < .001) with birth weight, umbilical cord weight, and total calculated umbilical cord glycogen and somewhat lower but significant (P < .037) direct correlations with the calculated mean umbilical cord glycogen level, total calculated placental glycogen content, and placental weight. The glycogen level in the middisk parenchymal section from the fetal surface correlated directly with gestational age. Periodic acid-Schiff stains showed that magenta glycogen granules were most abundant in the cytoplasm of the vascular smooth muscle cells. These data show significant variations in glycogen levels among sampling sites. Definition of the precise sampling site is important for clinicopathologic studies of placental glycogen and for interstudy correlations.


Assuntos
Membranas Extraembrionárias/química , Glicogênio/análise , Placenta/química , Cordão Umbilical/química , Humanos
11.
Blood ; 86(6): 2419-28, 1995 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-7662990

RESUMO

We report on a second generation of transgenic mice produced by crossing a transgenic mouse line expressing high levels of human alpha and beta S chains (alpha H beta S [beta MDD]) with a line expressing human alpha and beta S-Antilles (beta SAnt). We hypothesized that mice expressing both hemoglobins (Hbs) would have a more severe phenotype because the reduced oxygen affinity and solubility of the beta S-Antilles might enhance the rate and extent of polymer formation. We obtained mice that expressed both beta S and beta S-Antilles. The doubly transgenic mice that are heterozygous for deletion of mouse beta Major (beta MD) occurred with reduced frequency and those that are homozygous for deletion of mouse beta Major (beta MDD) occurred at a much reduced frequency and suffered early mortality. Human alpha was 58% of all alpha globin for all animals, whereas beta S and beta S-Antilles were 34% and 28% of all beta globins for beta MD mice and 42% and 36% for beta MDD mice. Hematocrit, Hb, and mean corpuscular Hb were normal for all transgenic mice, but reticulocyte levels were higher for the doubly transgenic mice versus alpha H beta S [beta MDD] mice older than 30 days (10.0% +/- 1.0% v 4.3% +/- 0.4%; P < .001, mean +/- SE, n = 20 and n = 10, respectively) and control mice (3.9% +/- 0.4%). Reticulocytosis was more severe in mice less than 30 days old ( > 20% for alpha H beta S beta S-Ant[beta MDD] mice). The median mean corpuscular hemoglobin concentration of doubly transgenic mice was higher than that of alpha H beta S[beta MDD] mice with a variable number of very dense cells. Delay times for polymerization of Hb in red blood cells from alpha H beta S beta S-Ant[beta MDD] mice were shorter than those of alpha H beta S[beta MDD] mice, and there were fewer cells with delay times greater than 100 seconds. Urine-concentrating ability in control mice under ambient conditions is 2,846 +/- 294 mOsm and was reduced 30% to 1,958 +/- 240 mOsm, P < 4 x 10(-8) in all mice expressing both transgenes. We conclude that doubly transgenic mice have a more severe phenotype than either of the two parental lines. These mice may be suitable for validating therapeutic intervention in sickle cell disease.


Assuntos
Anemia Falciforme/genética , Modelos Animais de Doenças , Globinas/genética , Hemoglobina Falciforme/genética , Camundongos Transgênicos/genética , Anemia Falciforme/sangue , Anemia Falciforme/patologia , Animais , Encéfalo/patologia , Centrifugação com Gradiente de Concentração , Cruzamentos Genéticos , Contagem de Eritrócitos , Eritrócitos Anormais , Hemoglobina Falciforme/biossíntese , Hemoglobinas/análise , Hemoglobinas Anormais/genética , Heterozigoto , Humanos , Rim/patologia , Fígado/patologia , Pulmão/patologia , Camundongos , Camundongos Transgênicos/sangue , Tamanho do Órgão , Concentração Osmolar , Fenótipo , Mutação Puntual , Proteínas Recombinantes/genética , Reticulócitos , Índice de Gravidade de Doença , Baço/patologia , Urina/química
12.
J Pediatr Surg ; 28(6): 770-2, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8331500

RESUMO

Intradural extension of a sacrococcygeal teratoma (SCT) is extremely rare and only well-documented in presacral tumors that have been associated with a familial history, anorectal stenosis, and sacral dysraphism. This case documents the extension of a type I SCT into the dural sac with attachment to the filum terminale. A full-term female was transferred to our tertiary newborn intensive care unit with a sacral mass measuring 12 x 13 cm. It protruded from the buttocks and displaced the anus anteriorly. Rectal examination showed no presacral component. Radiographs demonstrated calcification in the soft tissue mass and a normal-appearing sacrum with the last sacral segment not visualized. At operation during dissection of the cephalad component, the SCT extended into the spinal canal. Neurosurgical consultation resulted in a sacral laminectomy which revealed the tumor to be attached to the tip of the filum terminale. The tumor was removed in toto with all sacral roots preserved. The infant required a second operation to revise a wound dehiscence and suspected cerebrospinal fluid leak. The final pathology report was benign SCT. Follow-up at 2 years showed no recurrence, normal sphincter tone, and a normal computed tomography scan. This represents the first well-documented intradural extension of a Type I SCT with attachment to the spinal cord. This extremely rare occurrence requires awareness with the availability of neurosurgical support to expedite operative management.


Assuntos
Canal Medular , Neoplasias da Medula Espinal/congênito , Teratoma/congênito , Feminino , Humanos , Recém-Nascido , Região Sacrococcígea , Neoplasias da Medula Espinal/diagnóstico , Neoplasias da Medula Espinal/patologia , Neoplasias da Medula Espinal/cirurgia , Teratoma/diagnóstico , Teratoma/patologia , Teratoma/cirurgia
14.
Gastroenterology ; 104(3): 906-9, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8095037

RESUMO

Collagenous colitis, a disorder characterized by increased subepithelial collagen deposition associated with an inflammatory infiltrate in the lamina propria, has been reported infrequently in children. An 8-year-old girl with collagenous colitis is described who presented with chronic watery diarrhea and abdominal pain. Biopsy specimens of the colonic mucosa showed the pathological features of collagenous colitis. The patient's symptoms resolved following corticosteroid therapy. Collagenous colitis should be considered in the differential diagnosis of children with chronic diarrhea.


Assuntos
Colite/metabolismo , Colágeno/metabolismo , Criança , Doença Crônica , Colite/tratamento farmacológico , Colite/patologia , Feminino , Humanos , Mucosa Intestinal/metabolismo , Recidiva , Sulfassalazina/uso terapêutico
15.
Pediatr Pathol ; 13(1): 75-81, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8474954

RESUMO

Archival autopsy studies of sickle cell disease have often been hampered by inadequate documentation of the genotype. Although the polymerase chain reaction (PCR) has been applied to the prenatal diagnosis of sickle cell disease, its use has not been reported in archival studies of sickle cell disease. In this study, DNAs from formalin-fixed, paraffin-embedded archival tissues were amplified by PCR and analyzed by dot-blot hybridization using allele-specific oligonucleotides. These S and C genotypes for 9 of 10 archival specimens studied blindly were correctly identified by PCR. The tenth specimen consistently failed to amplify by PCR, yielding no result. These data demonstrate the utility of PCR for retrospective identification of the genotype of sickle cell disease. This application of PCR will significantly expand the number of autopsy cases suitable for retrospective studies of the morbidity and mortality of sickle cell disease.


Assuntos
Anemia Falciforme/genética , Reação em Cadeia da Polimerase/métodos , Anemia Falciforme/sangue , Anemia Falciforme/diagnóstico , Autopsia , Criança , DNA/genética , Estudos de Avaliação como Assunto , Genótipo , Hemoglobinas/genética , Humanos , Estudos Retrospectivos , Preservação de Tecido
16.
J Perinatol ; 12(1): 41-7, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1560290

RESUMO

The hemodynamics of critical aortic stenosis in the fetus make it a ductus-dependent cardiac defect because the ductus arteriosus supplies blood not only to the descending aorta but also to the aortic arch and coronary vessels. In utero closure of the ductus arteriosus has been reported in association with tetralogy of Fallot, truncus arteriosus, maternal use of prostaglandin inhibitors, and as idiopathic events. This is the first report of a ductus-dependent congenital heart defect (critical aortic stenosis) where treatment with indomethacin, a prostaglandin synthetase inhibitor, precipitated premature closure of the ductus and hydrops fetalis. Review of reported cases of premature closure of the ductus show that acute, in utero closure of the ductus in a fetus with limited cardiopulmonary reserves has a worse prognosis than with previously reported cardiac anomalies. This study strongly supports published concerns of increased perinatal morbidity and mortality when fetuses are exposed to prostaglandin inhibitors in utero, and shows that ductus-dependent fetal cardiac defects are contraindications to the maternal use of prostaglandin inhibitors during pregnancy.


Assuntos
Estenose da Valva Aórtica , Permeabilidade do Canal Arterial/fisiopatologia , Canal Arterial/fisiologia , Hidropisia Fetal/induzido quimicamente , Indometacina , Tocólise , Adulto , Contraindicações , Canal Arterial/efeitos dos fármacos , Feminino , Humanos , Indometacina/uso terapêutico , Recém-Nascido , Masculino , Gravidez
17.
Gastroenterology ; 101(5): 1420-7, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1936813

RESUMO

A 21-day-old infant presented with anemia, conjugated hyperbilirubinemia, hypoproteinemia, and a severe coagulopathy. The hospital course was marked by progressive hepatic failure, encephalopathy, and renal insufficiency. The infant died on day 15 of hospitalization. Postmortem examination showed diffuse hepatic fibrosis and marked siderosis of the liver, pancreas, kidney, adrenal glands, and the duodenal epithelium, with sparing of the reticuloendothelial system. These findings were characteristic of idiopathic neonatal iron-storage disease. Previously reported cases are summarized and discussed. An increased awareness and understanding of this rapidly fatal disorder will be important for genetic counseling and possibly in defining an aberrant mechanism in the handling of iron.


Assuntos
Hemocromatose , Transtornos da Coagulação Sanguínea/etiologia , Edema/etiologia , Feminino , Hemocromatose/sangue , Hemocromatose/complicações , Hemocromatose/patologia , Humanos , Recém-Nascido , Ferro/metabolismo , Icterícia/etiologia , Fígado/patologia , Masculino
18.
J Pediatr Surg ; 26(8): 930-5, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1919986

RESUMO

Ischemia-reperfusion injury has been implicated as playing a major role in the development of necrotizing enterocolitis, a major cause of morbidity and mortality in the newborn. A tungsten-supplemented molybdenum-free diet can reduce xanthine oxidase (XO) enzyme activity in the intestine, which in turn reduces the generation of oxygen radicals after an ischemia-reperfusion insult. This study evaluated the ability of this diet to be effective by indirect means, ie, transplacental and breast-feeding routes. XO activity of the intestine was measured in three groups of CD-1 white rats: I, weanlings fed the tungsten diet or standard chow for 1 week; II, 1-day-old rat pups whose mothers were maintained on the tungsten or standard chow for 7 to 10 days prior to term; and III, rat pups at 1 and 3 weeks after birth whose lactating mothers were maintained on the tungsten or standard chow. Some animals from group III also underwent either a 30- or 60-minute episode of occlusion of the superior mesenteric artery (SMA) to evaluate the protective effects of the diet. XO activity was significantly reduced in all groups receiving the tungsten diet (P less than .0001). Blinded histopathologic studies of the entire small bowel showed significantly less villar necrosis (P less than .05) and fibrosis (P less than .0001) in the tungsten-treated group than in the controls. In the 60-minute occlusion study all tungsten-group animals survived, whereas 7 of 12 in the control group died of intestinal infarction within 24 hours (P less than .001).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Intestino Delgado/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Tungstênio/administração & dosagem , Xantina Oxidase/metabolismo , Animais , Aleitamento Materno , Enterocolite Pseudomembranosa/etiologia , Enterocolite Pseudomembranosa/patologia , Feminino , Radicais Livres , Intestino Delgado/enzimologia , Placenta , Gravidez , Ratos , Traumatismo por Reperfusão/complicações , Tungstênio/farmacologia
19.
Blood ; 75(1): 274-83, 1990 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-2294992

RESUMO

A longitudinal, prospective, controlled evaluation of magnetic resonance images (MRI) of long bones in sickle cell patients was undertaken simultaneously with assessment of clinical status and hematologic parameters, including dense erythrocytes. MRI of bone marrow in sickle cell patients during steady states appeared patchy and were markedly different from those in matched controls (P approximately 0). Patients with severe patchiness were older than those with mild or moderate patchiness (P less than .03). Sixty-nine MRI were performed during 28 painful episodes occurring in 14 subjects with sickle cell disease (SCD). Increased signals on intermediate and T2-weighted images were detected in 35.7% of painful episodes. These abnormalities were distinct and not observed to occur spontaneously during the steady-state examinations (P approximately 0). Bone marrow infarcts were confirmed by biopsy in two instances and autopsy in one instance. Dense red cells decreased by 40.81% of baseline during pain crises (P = .00005), more remarkably in those who had pain in the lower extremities (P = .0145). Patients with change in MRI during pain crises had a greater percentage change in the dense cells than those without the change in MRI (69.7% v 31.3%, P = .0120).


Assuntos
Anemia Falciforme/diagnóstico , Medula Óssea/patologia , Anemia Falciforme/patologia , Autopsia , Biópsia , Doença da Hemoglobina SC/diagnóstico , Doença da Hemoglobina SC/patologia , Humanos , Imageamento por Ressonância Magnética , Necrose/diagnóstico , Estudos Prospectivos , Talassemia/diagnóstico , Talassemia/patologia
20.
Placenta ; 10(4): 417-25, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2780518

RESUMO

Although many studies in animal models and in cell cultures have shown that vanadate has insulin-like effects, it has not been studied in human diabetes mellitus. In this study the levels of vanadium in human placentae from 23 pregnancies complicated by gestational diabetes mellitus were compared with 18 uncomplicated non-diabetic pregnancies closely matched for maternal age, gravidity, and gestational age. Using the unpaired Student's t-test, the mid-disc placental levels in gestational diabetes (7.62 +/- 1.29 micrograms/g dry weight) were significantly lower (p less than 0.05) than controls (8.73 +/- 1.85 micrograms/g dry weight). These findings appear to be independent of placental size and birthweight. When these data were analyzed according to treatment, the vanadium levels in insulin-treated cases (8.07 +/- 1.32 micrograms/g dry weight) were not significantly different from the matched controls (8.84 +/- 1.69 micrograms/dry weight); the levels in noninsulin treated cases (7.08 +/- 1.25 micrograms/g dry weight), however, were significantly (p less than 0.005) lower than controls (8.99 +/- 1.96 micrograms/g dry weight). It is interesting to speculate that there may be increased binding of vanadium to maternal tissues in human diabetes mellitus when insulin is deficient.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Placenta/metabolismo , Gravidez em Diabéticas/metabolismo , Vanádio/metabolismo , Adolescente , Adulto , Feminino , Macrossomia Fetal/metabolismo , Humanos , Gravidez
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