Use of Leu M1 and antiepithelial membrane antigen monoclonal antibodies for diagnosing Hodgkin's disease

Biopsies of 82 patients diagnosed as having Hodgkin's disease were reviewed. Seventeen were reclassified histologically as non-Hodgkin's lymphoma or reactive lymphoid hyperplasia. A substantial number of cases of Hodgkin's disease were negative when stained with Leu M1. Staining for Leu M1 was not found in the cases of non-Hodgkin's lymphoma or reactive lymphoid hyperplasia. With the exception of the lymphocyte predominant nodular subtype of Hodgkin's disease, epithelial membrane antigen staining was seen in a few cases of Hodgkin's disease and non-Hodgkin's lymphomas. This was not a useful discriminating feature.     

X-linked mixed deafness (DFN3): cloning and characterization of the critical region allows the identification of novel microdeletions

We have found that the microsatellite marker AFM207zg5 (DXS995)maps to all previously described deletions which are associatedwith X-linked mixed deafness (DFN3) with or without choroideremiaand mental retardation. Employing this marker and pHU16 (DXS26)we have identified two partially overlapping yeast artificialchromosome clones which were used to construct a complete 850kb cosmid contig. Cosmids from this contig have been testedby Southern blot analysis on DNA from 16 unrelated males withX-linked deafness. Two novel microdeletions were detected inpatients which exhibit the characteristic DFN3 phenotype. Bothdeletions are completely contained within one of the known DFN3-deletions,but one of them does not overlap with two previously describeddeletions in patients with contiguous gene syndromes consistingof DFN3, chorolderemia, and mental retardation. Assuming thatonly a single gene is involved, this suggests that the DFN3gene spans a chromosomal region of at least 400 kb.     

The role of HIV-related chemokine receptors and chemokines in human erythropoiesis in vitro

In order to better define the role of HIV-related chemokines in human erythropoiesis we studied: A) the expression of chemokine receptors, both on human CD34(+) cells which include erythroid progenitors and on more mature erythroid cells; B) the functionality of these receptors by calcium flux, chemotaxis assay and phosphorylation of mitogen-activated protein kinases (MAPK) p42/44 (ERK1/ERK2) and AKT, and finally C) the influence of chemokines on BFU-E formation. We found that HIV-related chemokine receptor CXCR4, but not CCR5, is detectable on human CD34(+) BFU-E cells. CXCR4 surface expression decreased during erythroid maturation, although CXCR4 mRNA was still present in cells isolated from differentiated erythroid colonies. SDF-1, a CXCR4 ligand, induced calcium flux and phosphorylation of MAPK (p42/44) and AKT in CD34(+)KIT(+) bone marrow mononuclear cells which contain BFU-E, as well as chemotactic activity of both human CD34(+) BFU-E progenitors and erythroid cells isolated from day 2-6 BFU-E colonies. Responsiveness to SDF-1 decreased when the cells differentiated to the point of surface expression of the erythroid-specific marker Glycophorin-A. In contrast, the CCR5 ligands (macrophage inflammatory protein-1alpha [MIP-1alpha], MIP-1beta, and RANTES) did not activate calcium flux, MAPK and AKT phosphorylation or chemotaxis of CD34(+)KIT(+) cells or cells isolated from the BFU-E colonies. Interestingly, none of the chemokines tested in this study had any effect on BFU-E colony formation. In conclusion, only CXCR4 is functional, and its specific ligand SDF-1 may therefore play an important role in the homing and/or retention of early erythroid precursors in the bone marrow environment.     

Increased poly(ADP-ribose) polymerase activity in lymphoblastoid cell lines from centenarians

 Poly(ADP-ribosyl)ation is a posttranslational modification of nuclear proteins which is catalyzed by poly(ADP-ribose) polymerase and represents an immediate response of eukaryotic cells to oxidative and other types of DNA damage. Previously a strong correlation had been detected between maximal poly(ADP-ribose) polymerase activity in permeabilized mononuclear leukocytes of various mammalian species and species-specific life span. To study a possible relation between longevity and poly(ADP-ribosyl)ation in humans we measured maximal oligonucleotide-stimulated poly(ADP-ribose) polymerase activity in permeabilized, Epstein-Barr virus transformed lymphoblastoid cell lines from a French population of 49 centenarians and 51 controls aged 20–70 years. Maximal enzyme activity was significantly higher in centenarians than in controls [median of controls: 9035 cpm/10⁶ cells (lower quartile: 6156; upper quartile: 11,410); median of centenarians: 10,380 cpm/10⁶ cells (lower quartile: 7994; upper quartile: 12,991); P=0.031 by Mann-Whitney U test]. In a subset of 16 controls and 24 centenarians, cellular poly(ADP-ribose) polymerase content was determined by quantitative western blotting, thus allowing the calculation of specific enzyme activity. The latter was significantly higher in centenarians (P=0.006), the median value for centenarians being about 1.6-fold that of controls. Specific poly(ADP-ribose) polymerase activity was a more powerful parameter for differentiating between centenarians and controls than enzyme activity relative to cell number. In addition, in a genetic association study we analyzed 437 DNA samples (239 centenarians and 198 controls) by PCR amplification of a polymorphic dinucleotide repeat located in the promoter region of the poly(ADP-ribose) polymerase gene in an attempt to detect an association between this polymorphic marker and variability of enzyme activity or human longevity. However, this genetic analysis revealed no significant enrichment of any of the alleles or genotypes identified among centenarians or controls, but its power was limited by the relatively weak hetero-zygosity of this polymorphic marker in our population (51%). Viewed together with previous results on poly(ADP-ribose) polymerase activity in various mammalian species, the present data provide further evidence for the notion that longevity is associated with a high poly(ADP-ribosyl)ation capacity. Received: 5 September 1997 / Accepted: 10 November 1997     

Primitive Neuroectodermal Tumors of the Central Nervous System

Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers.     

Helicobacter pylori gastric infection in gnotobiotic beagle dogs.

Establishment of infection with Helicobacter pylori and gastritis in nonhuman species is currently only successful in gnotobiotic piglets. This study was designed to determine whether H. pylori will colonize the gastrointestinal tract of gnotobiotic dogs. Gnotobiotic beagle pups were derived by standard methods. Group A (five dogs) was orally challenged with 3 x 10(8) H. pylori at 7 days of age. Group B (two dogs) received only peptone water but was contact-exposed beginning on day 23 postinfection (p.i.). Necropsy was performed on dogs on day 30 p.i. H. pylori colonized the stomach of all dogs (groups A and B). Urease map analysis correlated with the microbiologic findings and indicated that the density of colonization was less than that observed in human tissue. Organisms were also recovered from the pharynx, esophagus, duodenum, and rectum of 1, 2, 2, and 1 dog, respectively. All group A and one group B dog developed serum immunoglobulin G specific for H. pylori by day 30 p.i. Gross lesions were restricted to the stomach and consisted of small (less than 1 mm) lymphoid follicles. Microscopically, there were focal to diffuse lymphoplasmacytic infiltrates with follicle formation and mild to moderate infiltration of neutrophils and eosinophils in the gastric lamina propria. With the Warthin-Starry silver stain, organisms were seen on the surface of the gastric epithelial cells, beneath the mucus layer. We conclude that H. pylori colonizes the stomachs of gnotobiotic dogs for at least 1 month and the lesions resemble those seen in humans. H. pylori is transmissible by contact from infected to noninfected dogs.     

Motor outcome according to the integrity of the corticospinal tract determined by diffusion tensor tractography in the early stage of corona radiata infarct

Diffusion tensor tractography (DTT) is useful for exploring the state of the corticospinal tract (CST). An accurate estimation of the integrity of the CST in the early stage of a cerebral infarct would enable a determination of motor recovery. DTT was performed to classify CST integrity following a corona radiata infarct to evaluate if the procedure could characterize the motor outcome of the affected hand. Fifty-five patients with completely paralyzed hands due to a corona radiata infarct were recruited for the study, and DTT images were obtained within 7–30 days after a stroke. The DTI findings for the patients were classified into four groups. In type A, the CST was preserved around the infarct; in type B, the CST originated from a cortex other than the primary motor cortex; in type C, the CST was interrupted at the infarct; in type D, the CST failed to reach the infarct due to degeneration. Six months after a stroke, the motor function of the affected hand was evaluated with the motricity index (MI) for the hand, the Medical Research Council score (MRC) for finger extensors and the modified Brunnstrom classification (MBC). These indices were significantly influenced by the DTT type (p < 0.05). The highest MI, MRC and MBC were seen in the DTT type A patients; the lowest MI, MRC and MBC were seen in the DTT type D patients (p < 0.05). The integrity of the corticospinal tract determined by DTT obtained during the early stage of a corona radiata infarct seems to be helpful in predicting the motor outcome of the affected hand.     

Klotho is a genetic risk factor for ischemic stroke caused by cardioembolism in Korean females

An aging-suppressor gene, klotho, is a candidate factor for vascular disease because its deficiency leads to impaired endothelium-dependent vasodilation and impaired angiogenesis. We investigated the association of polymorphisms in klotho with ischemic stroke. We searched for sequence variants in promoter and exons of klotho gene. For the association study, selected variants were genotyped in control subjects and in patients with ischemic stroke and vascular dementia. The association with ischemic stroke was further investigated with its subtypes classified based on Trial of Org 10172 in Acute Stroke Treatment (TOAST). No significant association was observed for both G-395A and C1818T with ischemic stroke and vascular dementia (P > 0.05). The analysis with subtypes of ischemic stroke revealed the associations that the A allele of G-395A increased the risk of cardioembolic stroke (CE, OR = 2.60; P = 0.006), and subjects carrying the A allele were susceptible to CE in both of dominant (AA + GA versus GG; OR = 2.50; P = 0.046) and recessive (AA versus GA + GG; OR = 6.52; P = 0.007) models. Further analysis of data partitioned by gender showed that the associations of G-395A with CE only existed in women (A versus G; OR = 4.33; P = 0.002), AA + GA versus GG; OR = 5.68; P = 0.014, and AA versus GA + GG; OR = 9.07; P = 0.012), but the significance disappeared in men (P > 0.05). The sequence variant of G-395A in klotho might be a genetic risk factor for CE in females.     

Effects of Crowding on the Thermal Stability of Heterogeneous Protein Solutions

Crowding can substantially affect the transition of a protein between its native (N) and unfolded (U) states via volume exclusion effects. Also, it influences considerably the aggregation (A) of unfolded proteins. To examine the details, we developed an approach for computing the kinetic rates of the process N ↔ U → A in which the concentration of the protein is explicitly taken into account. We then compute the relative change with temperature of the protein denaturation for various fractional volume occupancies and partition of proteins in solution. The analysis indicates that, in protein solutions in which the average distance between proteins is comparable with the radius of gyration of an unfolded protein, steric effects increase the stability of the proteins which are in compact, native states. In heterogeneous protein solutions containing various types of proteins with different thermal stabilities, the unfolding of the most thermolabile proteins will increase the stability of the other proteins. The results shed light on the way proteins change the thermal stability of a cell as they unfold and aggregate. This study may be valuable in questions related to the dynamics of thermal injuries.