Auditory sensory memory as indicated by mismatch negativity in chronic alcoholism.

OBJECTIVES: A pre-conscious auditory sensory (echoic) memory of about 10 s duration can be studied with the event-related brain potential mismatch negativity (MMN). Previous work indicates that this memory is preserved in abstinent chronic alcoholics for a duration of up to 2 s. The authors' aim was to determine the integrity of auditory sensory memory as indexed by MMN in chronic alcoholism, when this memory has to be functionally active for a longer period of time. METHODS: The presence of MMN for stimuli that differ in duration was tested at memory probe intervals (MPIs) of 0.4 and 5.0 s in 17 abstinent chronic alcoholic patients and in 17 healthy age-matched control subjects. RESULTS: MMN was similar in alcoholics and controls when the MPI was 0.4 s, whereas MMN could not be observed in the patients when the MPI was increased to 5.0 s. CONCLUSIONS: These results provide evidence of an impairment of auditory sensory memory in abstinent chronic alcoholics, whereas the automatic stimulus-change detector mechanism, involved in MMN generation, is preserved.     

Successful donor lymphocyte infusion for Epstein-Barr virus-associated lymphoproliferative disorder after allogeneic bone marrow transplantation from an HLA 1-locus-mismatched sibling donor in a patient with acute lymphocytic leukemia]

We report a case of Epstein-Barr virus-associated lymphoproliferative disorder (EBV-LPD) after allogeneic bone marrow transplantation (allo-BMT) from a partially mismatched related donor for acute lymphocytic leukemia, which was treated successfully by donor lymphocyte infusion (DLI). A 54-year-old woman in first complete remission from acute lymphocytic leukemia received an unmanipulated bone marrow transplant from an HLA-A 1-locus-mismatched sibling donor after preconditioning with cyclophosphamide and total body irradiation. Prophylaxis against graft-versus-host disease (GVHD) was done with tacrolimus and short-term methotrexate. Skin GVHD (grade I) occurred on day 36, but this subsided spontaneously without treatment. On day 61, rapidly progressive cervical lymphadenopathy with fever developed. Lymph node biopsy revealed lymphoid cell proliferation, which was positive for LCA, L26 and LMP-1. A diagnosis of EBV-LPD was made. After withdrawal of the tacrolimus, DLI (1 x 10(6) CD3 cells/kg) resulted in remission. This case suggests that even in the absence of risk factors such as severe GVHD, intensive immunosuppressive therapy and ATG administration, allo-BMT from an HLA 1-locus-mismatched related donor can be complicated by EBV-LPD, and that reduction of immunosuppressive therapy and DLI can be an effective treatment for it.     

Multicentric giant lymph node hyperplasia, plasma cell type, with monoclonal gammopathy

The association of multicentric giant lymph node hyperplasia (MGLH) of plasma cell type with monoclonal gammopathy was observed in a 37-year-old man. The present case provides an additional new piece of evidence that MGLH is by no means a benign disorder but can transform into plasma cell dyscrasia or B-cell lymphoma.     

Dimerization of a selectin and its ligand stabilizes cell rolling and enhances tether strength in shear flow

Selectins mediate rolling of leukocytes by rapid formation and dissociation of selectin-ligand bonds, which are assumed to require high mechanical strength to prevent premature dissociation by the forces applied in shear flow. This assumption is based largely on the observation that increasing wall shear stress increases only modestly the dissociation of transient leukocyte tethers on very low selectin densities. P-selectin binds to the N-terminal region of P-selectin glycoprotein ligand-1 (PSGL-1), a mucin on leukocytes. Both PSGL-1 and P-selectin are extended homodimers. We perfused transfected cells expressing wild-type dimeric PSGL-1 or a chimeric monomeric form of PSGL-1 on immobilized dimeric or monomeric forms of P-selectin. Cells expressing dimeric or monomeric PSGL-1 tethered to P-selectin at equivalent rates. However, cells expressing dimeric PSGL-1 established more stable rolling adhesions, which were more shear resistant and exhibited less fluctuation in rolling velocities. On low densities of dimeric P-selectin, increasing wall shear stress more rapidly increased transient tether dissociation of cells expressing monomeric PSGL-1 than dimeric PSGL-1. Tether dissociation on low densities of monomeric P-selectin was even more shear sensitive. We conclude that dimerization of both PSGL-1 and P-selectin stabilizes tethering and rolling, probably by increasing rebinding within a bond cluster. Because transient tethers may have more than one bond, the mechanical strength of selectin-ligand bonds is likely to be lower than initially estimated. Tether strength may rely more on bond clusters to distribute applied force.     

Murine neutrophils require alpha1,3-fucosylation but not PSGL-1 for productive infection with Anaplasma phagocytophilum

Anaplasma phagocytophilum causes human granulocytic ehrlichiosis, the second most common tick-borne disease in the United States. Mice are natural reservoirs for this bacterium and man is an inadvertent host. A phagocytophilum's tropism for human neutrophils is linked to neutrophil expression of P-selectin glycoprotein ligand-1 (PSGL-1), as well as sialylated and alpha1,3-fucosylated glycans. To determine whether A phagocytophilum uses similar molecular features to infect murine neutrophils, we assessed in vitro bacterial binding to neutrophils from and infection burden in wild-type mice; mice lacking alpha 1,3-fucosyltransferases Fuc-TIV and Fuc-TVII; or mice lacking PSGL-1. Binding to Fuc-TIV-/-/Fuc-TVII-/- neutrophils and infection of Fuc-TIV-/-/Fuc-TVII-/- mice were significantly reduced relative to wild-type mice. A phagocytophilum binding to PSGL-1-/- neutrophils was modestly reduced, whereas sialidase treatment significantly decreased binding to both wild-type and PSGL-1-/- neutrophils. A phagocytophilum similarly infected PSGL-1-/- and wild-type mice in vivo. A phagocytophilum induced comparable levels of chemokines from wild-type and PSGL-1-/- neutrophils in vitro, while those induced from Fuc-TIV-/-/Fuc-TVII-/- neutrophils were appreciably reduced. Therefore, A phagocytophilum infection in mice, as in humans, requires sialylation and alpha1,3-fucosylation of neutrophils. However, murine infection does not require neutrophil PSGL-1 expression, which has important implications for understanding how A phagocytophilum binds and infects neutrophils.     

Periodontal inflamed surface area and periodontal case definition classification

Objective: To assess whether a higher periodontal inflamed surface area (PISA) may reflect more severe periodontitis, and if so, to calculate which cut-off point should be used to classify a patient as suffering from periodontitis.

Material and methods: Eighty subjects were selected based on their periodontal status and were divided into 4 groups of 20 each; periodontally healthy, mild periodontitis, moderate periodontitis and severe periodontitis. In addition, demographic data, smoking status and socioeconomic status were also recorded.

Results: The highest mean PISA value was obtained for the severe periodontitis group (2309.42?±?587.69?mm²) and the least for the periodontally healthy (34.30?±?16.48?mm²). The PISA values corresponding to the three categories of periodontitis severity were significantly higher than the periodontally healthy group. When receiver operating characteristic (ROC) analysis was performed, a PISA value ≥130.33?mm² predicted the presence of periodontitis with a sensitivity of 98% and a specificity of 100%.

Conclusions: PISA is a periodontal parameter that may be used in conjunction with the Centers for Disease Control and Prevention – American Academy of Periodontology case definition classification in periodontal medicine research.     

Omega 3 polyunsaturated fatty acids and body weight

In animal studies, n-3 PUFA have been shown to influence body composition and to reduce the accumulation of body fat, thereby affecting body weight homeostasis. In addition, it has been suggested that an additional supply of n-3 PUFA during pregnancy or lactation, or both, would have a beneficial effect on birth weight and infant growth and development. The purpose of the present study was to systematically review interventional clinical trials on the effects of dietary n-3 PUFA supplementation on body weight in adult subjects and in infants whose mothers were supplemented with these fatty acids during pregnancy and/or lactation. A systematic search, focused on n-3 PUFA and body weight, and limited to controlled clinical trials, was performed in different databases. The quality of all included studies was assessed against set criteria, and results of eligible trials were compared. There were few studies targeting this topic. In adults, all of the five studies included, except for one, show no change in body weight by dietary supplementation with n-3 PUFA. Within those trials conducted in pregnant and/or lactating women in which a main outcome was birth weight or growth in infancy, two showed a modest increase in birth weight and the rest showed no effect. None of the trials showed an effect of maternal n-3 PUFA supplementation on infant's weight at the short term. However, it should be noted that a number of limitations, including a variety of experimental designs, type and doses of n-3 PUFA, and high attrition rates, among others, make impossible to draw robust conclusions from this review.     

Hypersensitivity to mosquito bite and malignant histocytosis

The follow-up data from 21 cases in Japan of severe local and constitutional hypersensitivity to mosquito bite (mosquito allergy) were collected. Three cases are now cured and no longer show hypersensitivity and 9 cases died, in 7 of these death being attributed to malignant histiocytosis (MH) or related conditions. In another case a systemic malignant neoplasm was suspected but was not confirmed as MH. Since both mosquito allergy and MH are exceedingly rare conditions, the association of the two is unlikely to be coincidental, and the possibility of a participation of viral infection is suspected as the cause of the systemic histiocytoses including MH.