bluuebunny/crossref_metadata_2025 huggingface dataset:
Omenn's Syndrome: Differential Diagnosis in Infants with Erythroderma and Immunodeficiency
Authors: Scheimberg Irene , Hoeger Peter H. , Harper John I. , Lake Brian , Malone Marian
Published: July 2002

The clinical differential diagnosis of erythroderma plus immunodeficiency and failure to thrive in neonates includes graft-versus-host-disease (GVHD), Omenn's syndrome (OS), and Netherton's syndrome (NS). In addition to immunological investigations, skin biopsy is an important part of the diagnostic work-up. We reviewed biopsies from 25 patients that were retrieved from the archives of the Department of Histopathology at Great Ormond Street, of which 9 were OS, 11 were GVHD, and 5 were NS. Five patients had two biopsy specimens. Both OS and GVHD show dyskeratosis and basal vacuolation. OS always shows acanthosis and almost always parakeratosis. GVHD shows a flat epidermis and rarely parakeratosis. OS and GVHD can be distinguished after immunohistochemistry for LCA and CD68 by the relative proportions of lymphocytes and macrophages in the dermal infiltrate (predominantly lymphocytes in OS, relatively more macrophages in GVHD). Skin biopsy diagnosis of OS is difficult before 6 weeks of age because the features are poorly developed. NS can be distinguished by psoriasiform acanthosis, thickening of the basement membrane, prominent dermal blood vessels, absence of dyskeratosis, and basal layer vacuolation, and a dermal infiltrate in which lymphocytes and macrophages are equally represented. Thus, the main difference between GVHD and OS is in the proportion of lymphocytes and macrophages in the infiltrate on immunohistochemical staining for LCA and CD68, while OS and NS may be distinguished on H&E morphology alone.
Primary Cardiac Lipoblastoma
Authors: Dishop Megan K. , O'Connor William N. , Abraham Simon , Cottrill Carol M.
Published: July 2002

Lipoblastoma is a benign adipose tumor in children that has been described in various anatomic locations, most commonly the extremities. We describe the case of a 17-month-old boy diagnosed with cardiac lipoblastoma, a previously unreported primary cardiac tumor in children. Our patient presented with symptoms of coughing, wheezing, and hoarseness and was found to have a large mediastinal mass, which narrowed the left mainstem bronchus and compressed the right atrium and superior vena cava, causing superior vena cava syndrome. Surgical exploration revealed an intrapericardial soft tissue mass arising from the area of the posterior interatrial septum. Grossly, the resected mass was lobulated, pale yellow, and fatty with focal areas of gray myxoid tissue. Microscopically, the tumor consisted of both immature and mature adipocytes, with focal vascular myxoid areas containing lipoblasts, diagnostic of lipoblastoma. Two months after surgery, the patient was in good health without evidence of recurrence.
Fascin and the Differential Diagnosis of Childhood Histiocytic Lesions
Authors: Jaffe Ronald , DeVaughn Donna , Langhoff Erik
Published: July 2002

This is a descriptive screening of 46 examples of childhood histiocytic lesions and some of their look-alikes using a monoclonal antibody, p55, to fascin. Fascin, an actin-bundling protein, identifies dendritic cells in the blood and in tissues. Our aim was to test the diagnostic utility of the antibody in various lesions at different sites and to see whether the staining patterns give insight into the cell types involved. Fascin intensely stained the cells of juvenile xanthogranulomas (JXG), Rosai-Dorfman lesions, and soft tissue dendrocytomas. Normal Langerhans' cells and the cells of Langerhans' cell histiocytosis were unreactive. Their lack of fascin staining may be relevant to fascin being maturation as well as lineage related. Epithelioid and palisading granulomas were unstained, though an example of Kikuchi lymphadenitis had large numbers of dendritic-type cells that stained strongly. A reticulohistiocytoma of the skin was also unstained and look-alike lesions, Spitz nevi, and mast cell lesions did not stain. Two of three large-cell lymphomas (both CD30+) also had fascin reactivity. Even though fascin is not specific to dendritic cells, staining other cell types as well (false positive), and not entirely sensitive, dendritic cells such as tissue Langerhans' cells are unstained (false negative), there seems to be a consistency of staining in childhood histiocytic lesions. This may be of diagnostic use when read in the context of the tissue differential diagnosis. Whether fascin can serve as a marker for the dendritic cell lineage, or at least for some phases of dendritic cell lifecycle, is not answered by this survey.
Monoclonal Gammopathy of the Immunoglobulin a Class in a Two-Year-Old Girl with Ataxia Telangiectasia
Authors: McDonald P.S. , Cora-Bramble D. , De Palma L.
Published: July 2002

Ataxia telangiectasia is an autosomal recessive neurologic disorder which is frequently associated with a deficiency of IgA immunoglobulin. We report an unusual case of monoclonal gammopathy of the IgA kappa type in a 2-year-old female patient newly diagnosed with ataxia telangiectasia. Quantitative analysis of the patient's immunoglobulins revealed a marked elevation in the IgA fraction with a value of 672 mg/dL (normal 14–123 mg/dL). The IgG and IgM fractions were normal. Serum protein electrophoresis showed a band of restricted mobility present in the gamma region, which was identified as a monoclonal IgA kappa immunoglobulin on immunofixation electrophoresis. This is the first case report of a patient with ataxia telangiectasia associated with an IgA monoclonal gammopathy.
Molecular Genetics in the Diagnosis and Prognosis of Solid Pediatric Tumors
Authors: Thorner Paul S. , Squire Jeremy A.
Published: July 2002

The field of molecular genetics continues to see an ever increasing number of applications to pediatric tumor analysis. Studies in pediatric tumors have identified novel genes and other genetic changes, a large number of which reflect one of the following mechanisms: ( 1) activation of proto-oncogenes; ( 2) loss of tumor suppressor genes; or ( 3) creation of novel fusion proteins. At least one of these mechanisms is operational in each of the following pediatric tumors: neuroblastoma, Ewing sarcoma and peripheral primitive neuroectodermal tumor (pPNET), intra-abdominal desmoplastic small-cell tumor, rhabdomyosarcoma, synovial sarcoma, and Wilms tumor. Out of this research has come not only an increased understanding of oncogenesis but also, for each of the tumors listed above, diagnostic and/or prognostic markers that can be used by the pathologist and oncologist to improve overall patient management.
Pathology of Lipomatous Lesions in Proteus Syndrome
Authors: Tihan Tarik , Okun Jonathan
Published: July 2002

Proteus syndrome is an extremely rare, complex hamartomatous disorder with markedly variable clinical expression. We present a case of Proteus syndrome with multiple disfiguring soft tissue masses that were present since early childhood. The lesions involved predominantly the right side of the body and included scoliosis, macrodactyly, and limited hyperostosis in the right foot. There was no evidence of cranial or skin lesions. The patient underwent multiple resections of soft tissue masses, including an amputation of the right foot because of severe gait disturbance. All specimens exhibited lipomatous lesions that were probably hamartomatous rather than neoplastic. She carried a diagnosis of neurofibromatosis for more than a decade, but a re-evaluation of clinical features and pathological findings prompted the diagnosis of Proteus syndrome. We believe that a more informed evaluation of the pathology material may help to identify this rare entity.
Biliary Atresia and Cytomegalovirus Infection: A DNA Study
Authors: Jevon G.P. , Dimmick J.E.
Published: July 2002

The cause of extrahepatic biliary atresia (EHBA) is undetermined in most instances, but an infectious agent is widely suspected. Cytomegalovirus (CMV) infection has been associated with intrahepatic bile duct destruction and paucity raising the question of its role in EHBA. We identified 12 children in the past 5 years with biliary atresia and examined the bile duct biopsy. These showed acute/chronic inflammation and epithelial degeneration. CMV inclusions were not identified. We used in situ hybridization and the polymerase chain reaction (PCR) for CMV-DNA on formalin-fixed, paraffin-embedded tissue. All samples showed the presence of amplifiable DNA using β-globin primers. No biopsy tissue showed CMV DNA using specific probes and primers. The absence of demonstrable CMV DNA by in situ hybridization and PCR in EHBA biopsies implies that it is unlikely that this virus has any major role in the pathogenesis of this condition.
Expression of WT1 in Pediatric Small Cell Tumors: Report of Two Cases with a Possible Mesothelial Origin
Authors: Thorner Paul , Squire Jeremy , Plavsic Natasha , Jong Roland , Greenberg Mark , Zielenska Maria
Published: July 2002

The WT1 gene is normally expressed in fetal kidney and mesothelium, and its expression has been suggested as a marker for Wilms tumor and mesothelioma. We examined WT1 expression levels by reverse-transcriptase polymerase chain reaction (RT-PCR) in 38 childhood small-cell tumors including Wilms tumor, embryonal and alveolar rhabdomyosarcoma, Ewing sarcoma, lymphoma, desmoplastic small round-cell tumor (DSRCT), synovial sarcoma, extrarenal rhabdoid tumor, and two tumors that were atypical for this group of tumors. WT1 expression was only detected in Wilms tumor, rhabdoid tumor, and in these two cases of uncertain histogenesis. Both arose in the peritoneal cavity and by immunohistochemistry were diffusely positive for vimentin, keratin, and desmin. Tonofilaments were identified by electron microscopy in one of the cases. RT-PCR failed to detect the t(11;22) translocation associated with DSRCT in either case. Our results suggest that WT1 expression is an unusual feature of childhood non-Wilms tumors and, in the right setting, it may indicate a mesothelial origin. The expression of WT1 may play a role in mesodermal cells acquiring epithelial characteristics, a concept supported by the mixed epithelial and mesenchymal phenotype of these two cases.
Huge Fetal Sacrococcygeal Teratoma with a Completely Formed Eye and Intratumoral DNA Ploidy Heterogeneity
Authors: Sergi Consolato , Ehemann Volker , Beedgen Bernhard , Linderkamp Otwin , Otto Herwart F.
Published: July 2002

Preterm infants and newborns with sacrococcygeal teratomas are at high risk for prenatal and perinatal complications. The prognosis depends on size and histology of the tumor, degree of prematurity, associated malformations, route of delivery, and prompt and complete surgical removal. Virtually any tissue can be present in a sacrococcygeal teratoma, but to date, ocular lens has been documented only as lentinoids (lens-like cells), whereas flow-cytometric data have been variably interpreted. We describe a case of a sacrococcygeal teratoma in an infant of 29 weeks gestational age that is remarkable for the weight (4500 g), the presence of a completely formed eye, and intratumoral DNA ploidy heterogeneity.
Case Report of a 22-Week Fetus with 47,XXX Karyotype and Multiple Lower Mesodermal Defects
Authors: Hoang Mai P. , Wilson Kathleen S. , Schneider Nancy R. , Timmons Charles F.
Published: July 2002

A 22-week stillborn fetus with 47,XXX karyotype had lower mesodermal defects consisting of irregular fusion of the sacral vertebrae, anal agenesis, multicystic dysplasia of a horseshoe kidney, a single umbilical artery, dysplastic ovaries, and uterine hypoplasia. This case provides additional evidence for an association between trisomy X and genitourinary defects including lower mesodermal defects sequence.
Autoimmune Enteropathy
Authors: Russo Pierre A. , Brochu Pierre , Seidman Ernest G. , Roy Claude C.
Published: July 2002

Autoimmune enteropathy (AIE) is an entity reported primarily in infancy, resulting in intractable diarrhea and associated with small bowel villous atrophy and the presence of circulating anti-enterocyte (AEA) antibodies. It is a multisystem disorder with a response, in many cases, to immunosuppressive therapy.
Maternally Inherited Mitochondrial Cardiomyopathy Associated with a C-to-T Transition at Nucleotide 3303 of Mitochondrial DNA in the tRNALeu(UUR) Gene
Authors: Goldstein Jeffrey D. , Shanske Sara , Bruno Claudio , Perszyk Anthony A.
Published: July 2002

Disorders associated with mitochondrial DNA (mtDNA) mutations are usually dominated by involvement of the nervous system and skeletal muscle (hence the term “mitochondrial encephalomyopathies”). However, considering the high dependence of the heart on oxidative metabolism, it is not surprising that myocardial dysfunction is often a prominent feature in these disorders, either as isolated cardiomyopathy or as part of a multisystem mitochondrial syndrome. We report an infant with a maternally inherited C-to-T transition at nucleotide 3303 of mtDNA in the tRNALeu(UUR) gene; this is the second kindred with cardiomyopathy identified to have this mutation of mitochondrial DNA. A brief review of other mitochondrial DNA defects is also included.
Basement Membranes in Development
Authors: Relan Nand K. , Schuger Lucia
Published: July 2002

The aim of this review is to introduce the reader to the main ECM constituents and to some of their roles in development. The main functions of the ECM during embryogenesis are the production, promotion, and regulation of normal tissue structure. Among the ECM components, LMs have been the most extensively studied in relation to embryo-genesis. Skin and skeletal muscle disorders have been shown to be caused by LM alterations. Additional experiments, e.g., with knockout mice, will help enormously to elucidate the functional significance of many ECM constituents and their involvement in development and disease.
Recent Trends in Chorangiomas, Especially those of Multiple and Recurrent Chorangiomas
Authors: Benirschke Kurt
Published: July 2002

The nomenclature and occurrence of chorangioma of the placenta are reviewed here. Recurrence of multiple chorangiomas has been described, but it is apparently an uncommon or underreported event. There is a strong relationship between placental chorangiomas and gestation at high altitude, suggesting the occurrence of vascular growth factors induced by hypoxia. Fluid transitions may exist between chorangioma, chorangiomatosis, and chorangiosis, although the latter is common in diabetic pregnancies, whereas chorangiomas are not so correlated.
Early History of Pathology Studies by the Intergroup Rhabdomyosarcoma Study Group
Authors: Newton William A. , Webber Bruce , Hamoudi Ala B. , Gehan Edmund A. , Maurer Harold M.
Published: July 2002

This review chronicles the series of publications that were the result of the willingness of pathologists and clinicians in the United States to share their pathologic materials and clinical data on patients who were placed on treatment protocols for rhabdomyosarcoma and related tumors over an extended period of time. The availability of this database enabled pathologists and clinicians to study a tumor type that is rare in individual institutions, but occurs in large enough numbers to produce valid conclusions not otherwise possible. Furthermore, young investigators were challenged by this opportunity and were able to spend the necessary time to make new observations that, in retrospect, helped direct protocol designs that produced significant improvement in patient survival. The key factor in this process is the surrender of individual scientific prerogatives to a small number of investigators. It is also important to recognize that the pathologist component of these series of contributions is only a part of the entire effort. It takes an organization of gifted, dedicated experts in many disciplines working together. The investigators who served on the Intergroup Rhabdomyosarcoma Group over a 25-year period eminently fulfilled this.
Sudden Death Due to Ventricular Septal Defect
Authors: Cohle Stephen D. , Balraj Elizabeth , Bell Michael
Published: July 2002

Ventricular septal defects (VSD) are usually considered non-life-threatening, usually closing spontaneously or causing symptoms of congestive heart failure, which can be surgically treated in time to save the patient's life. Despite the usually benign clinical course of VSD, serious arrhythmias occur in 16–31% of patients. Sudden death accounted for one-third of all deaths in a series of medically managed patients and occurred in 4.2% of patients in a study of VSD and arrhythmias. Cardiac hypertrophy is the common denominator in all cases reported in detail of VSD-associated sudden death. We have encountered four cases of sudden unexpected death from VSD in infants ranging in age from 1 week to 3 and ½ months. In each case there was cardiomegaly and in one case there was pulmonary arteriolar medial thickening, with extension of smooth muscle into small intralobular vessels. In half of our cases the attending physician was sued for malpractice. We believe that VSD in infants and young children are potentially life-threatening malformations which warrant careful clinical follow-up.
Immunolocalization of Transforming Growth Factor a and Epidermal Growth Factor Receptor in Lungs of Patients with Cystic Fibrosis
Authors: Hardie William D. , Bejarano Pablo A. , Miller Mary Ann , Yankaskas James R. , Ritter Jon H. , Whitsett Jeffrey A. , Korfhagen Thomas R.
Published: July 2002

Transforming growth factor α (TGF-α) is expressed in respiratory epithelial cells and alveolar macrophages during development and following lung injury. In the present study the presence and sites of synthesis of TGF-α and its receptor, the epidermal growth factor receptor (EGF-R), were assessed in lung tissue from patients with severe lung disease caused by cystic fibrosis (CF). Lung sections from 24 individuals with CF, obtained at the time of lung transplantation, were compared to lung sections from five lung donors without CF. Cellular sites of TGF-α, EGF-R, and cellular sites of proliferation were assessed by immunohistochemistry All CF lung sections contained multiple cell types with detectable TGF-α. Compared to control sections, intensity of TGF-α immunostaining in macrophages, airway epithelial cells, and peribronchial submucosal cells was increased. EGF-R was detected in respiratory epithelial and peribronchial stromal cells but not in alveolar macrophages. The intensity of EGF-R staining in CF lung tissue did not differ from that of controls. An increased number of cells expressing Ki-67 nuclear antigen was detected in peribronchial submucosal cells but not bronchiolar epithelial cells in the CF lungs. The increased expression of TGF-α in CF lung tissue supports the concept that TGF-α plays a role in paracrine/autocrine regulation of lung remodeling associated with injury and repair in the lungs of individuals with cystic fibrosis.
Investigation of Nonimmune Hydrops Fetalis: Multidisciplinary Studies are Necessary for Diagnosis— Review of 94 Cases
Authors: Lallemand Aude V. , Doco-Fenzy Martine , Gaillard Dominique A.
Published: July 2002

This review of 94 cases of nonimmune hydrops fetalis (NIHF) over a 10-year period was undertaken to evaluate the frequency of this pathology among fetal and infant deaths and to determine the most common likely etiologies in a northeastern region of France. NIHF represented 6% of the fetal deaths examined in our laboratory. The combination of findings from morphologic examination of the placenta and fetus with the results of microbiological and cytogenetic investigations (conventional cytogenetic study, fluorescent in situ hybridization [FISH], or DNA ploidy image analysis) led to an etiologic diagnosis for NIHF in two-thirds of the cases and suggested a diagnosis in an additional 23% of cases. The most common causes of NIHF were chromosome abnormalities (33%), infections (16%), and cardiac pathology (13.8%). The detection of a cause for NIHF is important for genetic counseling and management of subsequent pregnancies. Our experience suggests that a diagnosis is possible in a large majority of NIHF when obstetricians and pathologists carefully coordinate the management of prenatal and postnatal investigations and when new techniques, such as molecular biology and DNA quantification, are used.
Chronic Intrauterine Meconium Aspiration Causes Fetal Lung Infarcts, Lung Rupture, and Meconium Embolism
Authors: Kearney Michael S.
Published: July 2002

Three neonates with chronic intrauterine meconium aspiration are reported. All had distinctive subpleural plate-infarcts of the lungs caused by meconium–induced vasoconstriction of peripheral preacinar arteries. These vessels showed plexogenic arteriopathy with medionecrosis and obliterative hyaline sclerosis. Organized thrombi and systemic-pulmonary arterial anastomoses were numerous. The infarcts contained inspissated meconium with a granulomatous reaction.

In one case, lung rupture occurred, causing meconiumthorax and meconium embolism to hilar lymphatics and lymph nodes; this suggests that particulate meconium may enter the circulation. This fetus had rubella and probable acute twin-twin transfusion following the intrauterine death of the co-twin. The cause of the hypoxia that led to intrauterine passage of meconium in the other cases is unknown. Meconium-stained amniotic fluid was noted in only one case.
Adrenal Vein Thromboses in an Infant of Diabetic Mother
Authors: Zhang Peilin , Masliah Eliezer
Published: July 2002

Maternal diabetes is common condition complicating pregnancy and may have serious consequences for the offspring. We report on an infant of a mother with multisubstance abuse and poorly controlled type I diabetes with complications that include multifocal fetal myocardial infarcts, macrosomia, hypoxic encephalopathy and islet cell hyperplasia, and bilateral adrenal vein thromboses with necrosis, a relatively rare complication of maternal diabetes.
Absence of Lamellar Bodies with Accumulation of Dense Bodies Characterizes a Novel Form of Congenital Surfactant Defect
Authors: Tryka A. Francine , Wert Susan E. , Mazursky Jon E. , Arrington Robert W. , Nogee Lawrence M.
Published: July 2002

Two female sibling full-term newborns developed respiratory distress shortly after birth, which progressed to respiratory failure. Tracheal lavage demonstrated presence of surfactant protein A (SP-A), but little surfactant protein B (SP-B), without aberrant surfactant protein C (SP-C). On a lung biopsy performed in both infants, prominent type II pneumocyte hyperplasia was evident. Through ultrastructural examination an absence of normally formed lamellar bodies was determined, with numerous irregular electron dense bodies within the type II pneumocytes. These electron dense bodies could also be identified in the alveolar spaces and alveolar macrophages. No alveolar tubular myelin was present. Abnormally high immunoreactivity for surfactant proteins SP-A, proSP-B, SP-B, and proSP-C was demonstrated by light microscopy. Presence of incompletely processed immunopositive proSP-B, but not proSP-C was observed in the alveolar lumina. No mutations in either the SP-B or SP-C gene were identified by sequence analysis of amplified cDNA. We conclude that these siblings exhibit an inherited surfactant deficiency characterized by abnormal accumulations of surfactant proteins within the pneumocytes. This abnormal accumulation may be due to a primary secretory defect, a defect in surfactant phospholipids, or an abnormal interaction between the phospholipids and surfactant proteins.
Mise en evidence de la formation d'un complexe ternaire entre trypsine, α2‐macroglobuline et inhibiteur basique de pancreas
Authors: Jacquot-Armand Y. , Krebs G.
Published: July 2002

Such differences suggest either that the contact site of trypsin for binding is not the same for each inhibitor or that the steric hindrance by macroglobulin prevents large inhibitors from reaching the active site. The pancreatic inhibitor can reach this site but its affinity is lower for the complex than for free trypsin.
Muscle glycolipids in inherited muscular dystrophy of chickens
Authors: Kundu Samar K. , Misra Lalit K. , Luthra Madan G.
Published: July 2002

Gangliosides and neutral glycolipids of muscles from normal and dystrophic chickens were studied. Total glycolipid content of the degenerating muscles was higher than the normal muscles. In addition, the myopathic muscles contained a ganglioside which was absent in the unaffected muscles from normal and dystrophic chickens. Based on the thin‐layer chromatographic mobility, treatment with neuraminidases from Vibrio cholerae and Arthrobacter ureafaciens, and reactivity of the asialo‐derivative towards anti‐ganglio‐N‐triaosylceramide antibody, the dystrophic‐specific ganglioside was tentatively identified as GM2. Data obtained from young and old dystrophic chickens suggested a direct relationship of this ganglioside to muscular dystrophy.
The complete amino acid sequence of the bifunctional α‐amylase/trypsin inhibitor from seeds of ragi (Indian finger millet, Eleusine coracana Gaertn.)
Authors: Campos F.A.P. , Richardson M.
Published: July 2002

The complete amino acid sequence of the bifunctional α‐amylase/trypsin inhibitor from ragi seeds was determined by analysis of fragments and peptides derived from the protein by cleavage with cyanogen bromide and by digestion with trypsin, chymotrypsin, thermolysin, the S. aureus V8 protease and a Pro‐specific protease. The molecular consists of a single polypeptide chain of 122 amino acids which exhibits sequence homology with trypsin inhibitors from barley and maize and with an α‐amylase inhibitor from wheat.
Thyroidal and neural control of myosin transitions during development of rat fast and slow muscles
Authors: Gambke Brigitte , Lyons Gary E. , Haselgrove John , Kelly Alan M. , Rubinstein Neal A.
Published: July 2002

Experiments with developing euthyroid, hypothyroid and hyperthyroid rats show that the transition from neonatal to adult fast myosin is orchestrated by thyroid hormones acting directly upon fast muscle cells. Denervation studies reveal the switch from neonatal to adult fast myosin synthesis is independent of the motoneuron. However the synthesis of slow myosin during development is critically dependent on innervation.
A novel type of crystallin in the frog eye lens
Authors: Tomarev Stanislav I. , Zinovieva Rina D. , Dolgilevich Svetlana M. , Luchin Sergey V. , Krayev Alexander S. , Skryabin Konstantin G. , Gause Georgyi G.
Published: July 2002

The nucleotide sequence of a cloned DNA coding for the 35‐kDa polypeptide of the eye lens of the frog Rana temporaria has been determined. The sequence without connectors and poly(A) tract is 889 nucleotides in length and shows no homology with sequences coding for other classes of crystallins; α‐, β‐, γ‐ or δ‐crystallins. The sequence contains one reading frame 675 nucleotides in length, an apparently intact 3′‐non‐translated region with the polyadenylation signal sequence and a poly(A) tract; the 5′‐non‐ translated region is lost along with part of the coding region; this accounts for about 1/4 of the total mRNA length. The secondary structure prediction according to the Ptitsin‐Finkelstein method shows the presence of predominantly β‐strands with only a few α‐helical regions. We conclude that the 35‐kDa polypeptide from the frog eye lens belongs to a new class of eye lens crystallins for which we propose the name ϵ‐crystallin.
Properties of ω‐cyclohexane fatty acids in membranes
Authors: Kannenberg E. , Blume A. , Poralla K.
Published: July 2002

The properties of di‐ω‐cyclohexyldodecanoylphosphatidylcholine (DCDPC) in various model membranes were studied by differential scanning calorimetry (DSC) and the monolayer technique. DCDPC shows a broad phase transition at 13°C with a total enthalpy of 4.1 as measured by DSC. In a DCDPC monolayer no phase transition was observed. At 25 the area increases linearly with temperature. The molecular area at 40°C and 25 equals that of dipalmitoylphosphatidylcholine. DCDPC liposome experiments show that the permeability of glycerol is strongly reduced above the phase transition in comparison with linear saturated fatty acid‐containing phosphatidylcholines of comparable chain lengths. These results suggest that lipids with ω‐cyclohexane fatty acids may possess a high acyl chain density at the free fatty acid end in the core of the membrane, which stabilizes the membrane and influences the permeability. This seems to be an important mechanism for membrane adaptation under various conditions for thermoacidophilic bacteria.
The Ca signal from fura‐2 loaded mast cells depends strongly on the method of dye‐loading
Authors: Almers W. , Neher E.
Published: July 2002

The Ca concentration ([Ca2+]i) in single rat peritoneal mast cells was measured by means of the new fluorescent Ca‐indicator dye fura‐2. Dye‐loaded cells were made to degranulate with either antigen or compound 48/80. In cells loaded with extracellularly applied, membrane‐permeant fura‐2 ester, degranulation was accompanied by a permanent loss of 40–60% of the fluorescence, but comparison of fluorescence at different wavelengths indicated no or only small changes in [Ca2+]i. When cells were loaded by microinjection of the impermeant potassium salt of the dye, degranulation resulted in no permanent loss of fluorescence, but instead was preceded by transient fluorescence changes that indicate a rapid, large and transient increase in [Ca2+]i. We suggest that ester‐loaded fura‐2 accumulates to a significant degree in the secretory granules and is lost from the cell during exocytosis.
Superoxide dismutase inhibits the superoxide‐driven Fenton reaction at two different levels
Authors: Gutteridge John M.C.
Published: July 2002

Superoxide dismutase (SOD) completely inhibits the damage caused by a ferric‐EDTA chelate in the presence of a superoxide‐generating system. In this reaction Superoxide is enzymically dismuted to hydrogen peroxide. Since hydrogen peroxide and a ferric‐EDTA chelate are themselves a hydroxyl radical‐generating system, it follows that SOD must also protect against damage done by this reaction. The ability of SOD to inhibit damage to deoxyribose caused by hydrogen peroxide and a ferric‐EDTA chelate is experimentally demonstrated in this paper.
Peroxisomal alanine:glyoxylate aminotransferase deficiency in primary hyperoxaluria type I
Authors: Danpure C.J. , Jennings P.R
Published: July 2002

Activities of alanine:glyoxylate aminotransferase in the livers of two patients with primary hyperoxaluria type I were substantially lower than those found in five control human livers. Detailed subcellular fractionation of one of the hyperoxaluric livers, compared with a control liver, showed that there was a complete absence of peroxisomal alanine:glyoxylate aminotransferase. This enzyme deficiency explains most of the biochemical characteristics of the disease and means that primary hyperoxaluria type I should be added to the rather select list of peroxisomal disorders.
Spectral, redox and kinetic characteristics of high‐potential cytochrome c hemes in Rhodopseudomonas viridis reaction center
Authors: Dracheva Stella M. , Drachev Lel A. , Zaberezhnaya Svetlana M. , Konstantincv Alexander A. , Semenov Alexey Yu. , Skulachev Vladimir P.
Published: July 2002

Redox, optical and kinetic characteristics of the four‐heme cytochrome c tightly bound to the reaction center complexes of Rhodopseudomonas viridis have been studied. The two high‐potential hemes, previously thought to be identical, are shown to differ in midpoint potentials, absorption spectra and kinetics of photooxidation. One heme is characterized by E
m = 380 ± 10 mV, and a split α‐band (a peak at 559 nm and a shoulder at 553 nm) whereas the other has an E
m = 310±10 mV and a symmetrical α‐band at 556 nm. Kinetics of laser flash oxidation of the c‐ heme by the photogenerated P‐960+ (τ ~ 0.3 μs) matches closely that of the bacteriochlorophyll reduction and precedes oxidation of the c‐556 heme, the latter occurring with τ ~ 2.5 μs concurrently with heme c‐ re‐reduction. The data point to heme c‐ being an immediate electron donor to P‐960+. Accordingly, this heme is tentatively identified with the iron‐porphyrin group proximal to the bacteriochlorophyll special pair in the three‐dimensional model of Rps. viridis reaction centers complexes [(1985) Nature 318, 618‐624]. Thus, the following reaction sequence is assumed: c‐556 → c‐559 → P‐960+.
Membrane translocation and insertion of NH2‐terminally anchored γ‐glutamyl transpeptidase require a signal recognition particle
Authors: Tate Suresh S. , Nash Barbara
Published: July 2002

The two subunits of the renal brush border enzyme, γ‐glutamyl transpeptidase (EC 2.3.2.2), are derived from a single‐chain propeptide. The membrane‐spanning domain consists of a hydrophobic sequence near its NH2‐terminus and the protein is oriented with its NH2‐terminus on the cytoplasmic side. The enzyme is synthesized without a cleavable signal sequence. Translocation and insertion of this enzyme have been shown to be dependent on the signal recognition particle and presumably require the same translocation machinery that other secretory and membrane proteins use for these processes.
Inhibition of protein breakdown by glutamine in perfused rat skeletal muscle
Authors: MacLennan Peter A. , Smith Kenneth , Weryk Brian , Watt Peter W. , Rennie Michael J.
Published: July 2002

We have assessed the effects of glutamine (Gln) availability on protein breakdown in perfused rat hindlimb by measuring net phenylalanine (Phe) production (an index of protein balance), the dilution of [15N]Phe labelling (an index of mixed protein breakdown) and rate of production of 3‐methylhistidine (3‐MeH) (an index of myofibrillar breakdown). 15 mM Gln significantly inhibited net protein loss and protein breakdown compared to rates obtained in its absence (net protein loss, 200±230 vs 2080±200 nmol Phe/hindlimb per h; protein breakdown, 4566±480 vs 1614±180 nmol Phe/hindlimb per h; both p<0.01). Insulin (100 μU/ml) inhibited protein breakdown but less than Gln. The effects on protein breakdown of Gln and insulin together were not additive, suggesting a common mode of action. Production of 3‐MeH (mean 20.3±2.8 nmol/hindlimb per h) was unaffected by Gln or insulin. Gln appears to inhibit protein breakdown of soluble rather than myofibrillar protein in muscle.
Sequencing and synthesis of pardaxin, a polypeptide from the Red Sea Moses sole with ionophore activity
Authors: Shai Yechiel , Fox Jay , Caratsch Carlo , Shih Yu-Liang , Edwards Charles , Lazarovici Philip
Published: July 2002

Pardaxin, an amphipathic polypeptide secreted by the Red Sea flatfish Pardachirus marmoratus whose sequence is NH2‐G‐F‐F‐A‐L‐I‐P‐K‐I‐I‐S‐S‐P‐L‐F‐K‐T‐L‐L‐S‐A‐V‐G‐S‐A‐L‐S‐S‐S‐G‐G‐Q‐E, was synthesized by the solid‐phase method. The structure was verified by sequencing. The synthetic polypeptide changed the resistance of lipid bilayers by forming pores. At 10−7−10−8 M, the synthetic pardaxin increased the frequency of the spontaneous release of quanta of acetylcholine at the neuromuscular junction by up to 100‐fold, resembling the native product. Synthetic pardaxin seems to be a suitable tool for investigating the molecular structures underlying channel selectivity.
Carbamate analogues of (−)‐physostigmine: In vitro inhibition of acetyl‐ and butyrylcholinesterase
Authors: Yu Qian-Sheng , Atack John R. , Rapoport Stanley I. , Brossi Arnold
Published: July 2002

Reaction of (−)‐eseroline (1) with alkyl, aryl and aralkylisocyanates afforded a series of carbamate analogues of (−)‐physostigmine (2) which were assayed for inhibition of acetyl‐ and butyrylcholinesterase (AChE and BChE, respectively) in vitro. Included in this study were two N‐alkyl‐substituted carbamates 9 and 14 obtained from (−)‐eseroline (1) with dialkylcarbamoyl chlorides, and allophanates 12 and 13 obtained as by‐products in the reaction of 1 and benzylcarbamoyl eseroline (8) with benzyl isocyanate. Whereas none of the analogues studied was more potent than 2 against electric eel AChE, and carbamates 6, 7 and 8 were all more than 3 times more potent against human plasma BChE than 2.
Transforming growth factor β stimulates collagen and glycosaminoglycan biosynthesis in cultured rabbit articular chondrocytes
Authors: Redini F. , Galera P. , Mauviel A. , Loyau G. , Pujol J.-P.
Published: July 2002

The effect of transforming growth factor β (TGF‐β) on the production of matrix macromolecules was studied in cultures of rabbit articular chondrocytes. A 24 h exposure to TGF‐β at concentrations of 0.1, 1 and 10 ng/ml markedly stimulated the synthesis of collagen and non‐collagen protein. Similar increases of glycosaminoglycan production was observed in the same experimental conditions. The distribution of these newly synthesized macromolecules between cell layer and medium was not altered by treatment with TGF‐β. The factor slightly enhanced the proliferation of chondrocytes in these experiments but its potent effect on matrix synthesis was independent of this growth stimulation. These results indicate that articular chondrocytes are target cells for TGF‐β and suggest that this growth factor could play a role in the repair process of cartilage during osteoarticular diseases.
Inhibition of target cell mitochondrial electron transfer by tumor necrosis factor
Authors: Lancaster Jack R. , Laster Scott M. , Gooding Linda R.
Published: July 2002

Using digitonin permeabilization to assay mitochondrial electron transfer, we have found that respiratory activity (succinoxidase and cytochrome oxidase) in three mouse fibroblast lines is completely eliminated by incubation with human recombinant tumor necrosis factor‐α (hrTNF). As with cytotoxicity, hrTNF‐induced mitochondrial dysfunction occurs in resistant cells upon inhibition of protein synthesis, whereas sensitive cells exhibit spontaneous respiratory inhibition. In C3HA cells, inhibition is detectable 1.5–2 h after hrTNF addition, preceding cell lysis by at least 5 h (as measured by dye exclusion), and is approximately coincidental with morphological changes we have previously reported for this cell line. LM cells also exhibit inhibition of electron transfer, coincidental with morphological changes. These results suggest that bioenergetic dysfunction may be involved in the cytotoxic mechanism of TNF.
Transcription of the dystrophin gene in Duchenne muscular dystrophy muscle
Authors: Muntoni Francesco , Strong Peter N.
Published: July 2002

Dystrophin is the recently discovered defective gene product in Duchenne and Becker muscular dystrophy (DMD and BMD). Dystrophin transcripts have been amplified and identified in diagnostic needle muscle biopsy samples using the polymerase chain reaction (PCR) procedure. Using 5′‐ and 3′‐primers, dystrophin transcripts can be detected in both DMD and BMD muscle biopsies, on either side of defined deletions within the dystrophin gene.
The protonated form of 1‐N6‐etheno‐[erythro‐9‐(2‐hydroxy‐3‐nonyl)] adenine is identified at the active site of adenosine deaminase
Authors: Caiolfa Valeria R. , Gill David , Parola Abraham H.
Published: July 2002

A novel fluorescent competitive inhibitor of adenosine deaminase (EC 3.5.4.4) (ADA), 1‐N
6‐etheno‐[erythro‐9‐(2‐hydroxy‐3‐nonyl)] adenine (ϵ‐EHNA), is protonated at the active site of the enzyme. In ϵ‐EHNA [K
1 = (4.06 ± 1.00) 10−6 M] part of the competive inhibition of EHNA is combined with spectroscopic properties of etheno‐adenines. Computer subtraction of the fluorescence excitation spectrum of ADA from that of its equimolar complex with ϵ‐EHNA yielded the corrected excitation spectrum of ϵ‐EHNA at the active site of the enzyme. This spectrum mimics that of ϵ‐EHNA at pH 5.5 in buffer solution and is suggested to indicate a shift in protonation equilibrium at the active site.
The γ subunit of brain G‐proteins is methyl esterified at a C‐terminal cysteine
Authors: Fung Bernard K.-K. , Yamane Harvey K. , Ota Irene M. , Clarke Steven
Published: July 2002

The γ polypeptide of brain G‐proteins is carboxyl methylated when the purified βγ subunit complex is reconstituted with S‐adenosyl‐[3H‐methyl]‐L‐methionine and a methyltransferase present in detergent‐stripped brain membranes. By Chromatographic analysis of the 3H‐amino acid generated by exhaustive proteolysis and performic acid oxidation of the 3H‐methylated βγ complex, we show that this modification occurs on the α‐carboxyl group of a C‐terminal cysteine residue. Our result suggests that brain G‐proteins may undergo multiple covalent modification steps, including proteolytic removal of the three terminal amino acids from the predicted common C‐terminal Cys‐Xaa‐Xaa‐Xaa sequence, and the methyl esterification of the resulting terminal cysteine residue. This modification is likely to be associated with lipidation at the sulfhydryl group of the same cysteine, which would explain the tight membrane binding property of the brain βγ complex.
Dual effect of arachidonic acid on protein kinase C isoenzymes isolated from rabbit thymus cells
Authors: Buday László , Faragó Anna
Published: July 2002

Type II and type III isoenzymes of protein kinase C isolated from rabbit thymus cells were activated at relatively low concentrations but were inhibited at higher concentrations of arachidonic acid. Activation by cis‐unsaturated fatty acids required Ca2+ the maximal activity was approached at about 10−6 M Ca2+ concentration. The kinetics of activation and inhibition by arachidonic acid depended strongly on the nature of the substrate (synthetic oligopeptide or H1 histone), on the concentration of the protein substrate and on the stage of purification of the isoenzyme preparation investigated. Activation seemed to be favoured at high protein concentrations.
Cloning and sequence analysis of the Erythrina corallodendron lectin cDNA
Authors: Arango Rafael , Rozenblatt Shmuel , Sharon Nathan
Published: July 2002

Examination of the hemagglutinating activity of extracts from seeds of Erythrina corallodendron at various maturation stages revealed that the level of lectin increases markedly past mid‐maturation. Seeds at this stage of maturation served as a source of mRNA for the construction of an expression cDNA library in the vector λ Zap, which generates fusion proteins with an N‐terminal portion of β‐galactosidase. The library was screened with rabbit polyclonal anti‐ECorL antiserum. Four immunopositive clones were isolated. Western blot analysis of cell extracts from one of the clones (pIEcL‐B) showed a 36 kDa protein that reacted with the antiserum, as well as with a mouse monoclonal antibody raised against the lectin. DNA sequence analysis by the chain termination method revealed that clone pIEcl‐C has an insert of 1017 bp with the entire coding sequence of ECorL, beginning with an initiation codon ATG at position 26 and ending with stop codon TAA at position 868. This fragment encodes a polypeptide of 281 amino acids consisting of a signal leader sequence of 25 amino acids and a mature protein of 256 amino acids. The deduced amino acid sequence from this fragment is identical to the sequence of the first 244 amino acids of ECorL, as determined at the protein level, except at 7 positions.
Inhibition of development of Na+‐dependent hexose transport in renal epithelial LLC‐PK1 cells by differentiation‐stimulating factor for myeloid leukemic cells/leukemia inhibitory factor
Authors: Tomida Mikio , Yamamoto-Yamaguchi Yuri , Hozumi Motoo , Holmes William , Lowe David G. , Goeddel David V.
Published: July 2002

Differentiation‐stimulating factor (D‐factor)/leukemia inhibitory factor is a cytokine inducing differentiation of mouse myeloid leukemie M1‐T22 cells. The effect of recombinant human D‐factor on growth and differentiation of pig kidney LLC‐PK1 cells was examined. LLC‐PK1 cells did not concentrate α‐methylglucoside during their early growth in culture but developed the capacity to concentrate this hexose as they reached confluence and their growth rate decreased. Purified D‐factor caused dose‐dependent inhibition of the development of this concentrative capacity. It did not affect the growth rate of the cells, but inhibited the formation of multicellular domes in confluent cultures. LLC‐PK, cells were found to have high‐affinity binding sites (831 per cell) for D‐factor with a dissociation constant of 197 pM.
Biosynthesis of paf‐acether XVII. Regulation by the CoA‐independent transacylase in human neutrophils
Authors: Ninio Ewa , Breton Michelyne , Bidault Jocelyne , Colard Odile
Published: July 2002

Treatment of intact human polymorphonuclear neutrophils (PMN) with low concentrations of phorbol myristate acetate (PMA, 1–10 ng/ml) induced paf‐acether (pat) and lyso paf formation, arachidonate release, and simultaneous inhibition of CoA‐independent lyso paf : transacylase as assayed in a cell‐free system. Inhibition of [3H]lyso paf reacylation was also observed when it was exogenously added to the PMA‐treated intact PMN. When higher concentrations of PMA (40–100 ng/ml) were used, paf biosynthesis was severely impaired and the level of the CoA‐independent transacylase activity returned to basal level. Since lyso paf appears to be the substrate for PMA‐activated paf formation (remodeling pathway), we showed that [14C]acetate was incorporated into the paf molecule. By contrast, labeling with [3H]choline was not appropriate in this model. The presented results are against the involvement of a de novo route in paf synthesis initiated by PMA and open a new possibility of an important role for the CoA‐independent transacylase in controling the level of lyso paf availability for paf formation.
Membrane‐bound apolipoprotein B is exposed at the cytosolic surface of liver microsomes
Authors: Wilkinson Jane , Higgins Joan A. , Groot P.H.E. , Gherardi E. , Bowyer D.E.
Published: July 2002

We have used a competitive enzyme‐linked immunoassay with a panel of monoclonal antibodies to probe the topography of the membrane‐bound form of apolipoprotein B (apo B) in rabbit microsomes. All epitopes investigated were found to be expressed at the cytosolic side of the microsomal membrane under conditions in which the vesicles remained sealed. These results indicate that the membrane‐associated form of apolipoprotein B is either at the cytosolic side of the endoplasmic reticulum membrane or integrated into the membrane. From this site apo B may be translocated to the lumen for assembly into VLDL or may be degraded.
Involvement of calpain in diamide‐induced cataract in cultured lenses
Authors: Azuma Mitsuyoshi , Shearer Thomas R.
Published: July 2002

Lenses cultured in diamide first developed outer cortical opacities followed by nuclear cataract. Lens hydration and total calcium were markedly increased by diamide. Proteolysis or crystallins were observed in nuclear cataract lenses. Calpain in the soluble fraction of lenses cultured with diamide was decreased, while calpain in the insoluble fraction was increased. Co‐culture with E64d, an inhibitor of cysteine protease such as calpain, especially prevented nuclear opacities and proteolysis of crystallins, indicating that calpain was involved in cataract formation by diamide.
Biologically relevant metal ion‐dependent hydroxyl radical generation An update
Authors: Halliwell Barry , Gutteridge John M.C.
Published: July 2002

Transition metal ions, especially iron, appear to be important mediators of oxidative damage in vivo. Iron(II) reacts with H2O2 to give more‐reactive radicals. On the basis of ESR spin‐trapping data with DMPO, supported by aromatic hydroxylation studies and patterns of DNA base modification, it is concluded that hydroxyl radical (OH•) is likely to be the major damaging species formed in Fenton Systems under biologically‐relevant conditions (which include iron concentrations no higher than the micromolar range). Although reactive oxo‐iron species (such as ferryl and perferryl) may also be important, chemical evidence for their formation and identity in biologically relevant Fenton systems is currently lacking. Studies at alkaline pH values show that iron(IV) and iron(V) species are highly oxidizing under those reaction conditions, with a pattern of reactivity different from that of OH•.