Immunological and molecular analysis of B lymphocytes in low-grade MALT lymphoma of the stomach. Are there any useful markers for predicting outcome after Helicobacter pylori eradication?

Background: Background: Although Helicobacter pylori eradication is effective in treating low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma, the condition in some patients deteriorates even after the eradication. Therefore, it is important to predict the disease outcome before starting H. pylori eradication. We investigated the usefulness of flow cytometry, quantifying CD19- and CD20-positive B lymphocytes in MALT lymphoma tissue, for predicting the disease outcome after H. pylori eradication. Methods: Tissue specimens from 14 patients with H. pylori-positive low-grade gastric MALT lymphoma were examined by histology, Southern blotting, and flow cytometry before therapy. Serum levels of soluble interleukin (IL)-2 receptor were also measured. The relationship between the data and the prognosis after H. pylori eradication was analyzed. Results: Remission occurred in 10 of the 14 patients. The condition in the 4 remaining patients deteriorated even after H. pylori eradication. The percentages of CD19- and CD20-positive cells in MALT lymphoma tissue from the patients in remission were both significantly lower than those in the tissue from patients not in remission. Indeed, 4 of the 5 patients in whom both CD19- and CD20-positive cells accounted for more than 50% of the total number of lymphocytes had gastrectomy, whereas all patients in whom both CD19- and CD20-positive cells accounted for less than 50% of the total number of lymphocytes achieved remission. Although immunoglobulin gene rearrangement was present in all patients operated on, there were also 6 patients whose MALT lymphoma was ameliorated in spite of the presence of gene rearrangement. The serum level of soluble IL-2 receptor was in the normal range in all patients tested. Conclusions: Analysis of mature B-cell markers in MALT lymphoma tissue is more useful than the examination of immunoglobulin gene rearrangement or serum levels of soluble IL-2 receptor in predicting the outcome of low-grade gastric MALT lymphoma after H. pylori eradication. Received: January 5, 2001 / Accepted: November 2, 2001     

Functional analysis of JAK3 mutations in transient myeloproliferative disorder and acute megakaryoblastic leukaemia accompanying Down syndrome

JAK3 mutations have been reported in transient myeloproliferative disorder (TMD) as well as in acute megakaryoblastic leukaemia of Down syndrome (DS-AMKL). However, functional consequences of the JAK3 mutations in TMD patients remain undetermined. To further understand how JAK3 mutations are involved in the development and/or progression of leukaemia in Down syndrome, additional TMD patients and the DS-AMKL cell line MGS were screened for JAK3 mutations, and we examined whether each JAK3 mutation is an activating mutation. JAK3 mutations were not detected in 10 TMD samples that had not previously been studied. Together with our previous report we detected JAK3 mutations in one in 11 TMD patients. Furthermore, this study showed for the first time that a TMD patient-derived JAK3 mutation (JAK3(I87T)), as well as two novel JAK3 mutations (JAK3(Q501H) and JAK3(R657Q)) identified in an MGS cell line, were activating mutations. Treatment of MGS cells and Ba/F3 cells expressing the JAK3 mutants with JAK3 inhibitors significantly decreased their growth and viability. These results suggest that the JAK3 activating mutation is an early event during leukaemogenesis in Down syndrome, and they provide proof-of-principle evidence that JAK3 inhibitors would have therapeutic effects on TMD and DS-AMKL patients carrying activating JAK3 mutations.     

Genetic Analysis of Non-Hydrogen Sulfide-Producing Salmonella enterica Serovar Typhimurium and S. enterica Serovar Infantis Isolates in Japan

Whole-genome sequencing of non-H₂S-producing Salmonella enterica serovar Typhimurium and S. enterica serovar Infantis isolates from poultry meat revealed a nonsense mutation in the phsA thiosulfate reductase gene and carriage of a CMY-2 β-lactamase. The lack of production of H₂S might lead to the incorrect identification of S. enterica isolates carrying antimicrobial resistance genes.     

Evidence for Reactivation of Human Herpesvirus 6 in Generalized Lymphadenopathy in a Patient with Drug-Induced Hypersensitivity Syndrome

The present case provides direct evidence of human herpesvirus 6 reactivation in resected lymph node tissue in a patient with drug-induced hypersensitivity syndrome. This case clearly demonstrates that appropriate pathological evaluation of lymphadenopathy for drug-induced hypersensitivity syndrome, which mimics malignant lymphoma in clinical, radiological, and pathological findings, is required.     

PAK1 Positively Regulates Oligodendrocyte Morphology and Myelination

The actin cytoskeleton is crucial for oligodendrocyte differentiation and myelination. Here we show that p21-activated kinase 1 (PAK1), a well-known actin regulator, promotes oligodendrocyte morphologic change and myelin production in the CNS. A combination of in vitro and in vivo models demonstrated that PAK1 is expressed throughout the oligodendrocyte lineage with highest expression in differentiated oligodendrocytes. Inhibiting PAK1 early in oligodendrocyte development decreased oligodendrocyte morphologic complexity and altered F-actin spreading at the tips of oligodendrocyte progenitor cell processes. Constitutively activating AKT in oligodendrocytes in male and female mice, which leads to excessive myelin wrapping, increased PAK1 expression, suggesting an impact of PAK1 during active myelin wrapping. Furthermore, constitutively activating PAK1 in oligodendrocytes in zebrafish led to an increase in myelin internode length while inhibiting PAK1 during active myelination decreased internode length. As myelin parameters influence conduction velocity, these data suggest that PAK1 may influence communication within the CNS. These data support a model in which PAK1 is a positive regulator of CNS myelination.SIGNIFICANCE STATEMENT Myelin is a critical component of the CNS that provides metabolic support to neurons and also facilitates communication between cells in the CNS. Recent data demonstrate that actin dynamics drives myelin wrapping, but how actin is regulated during myelin wrapping is unknown. The authors investigate the role of the cytoskeletal modulator PAK1 during differentiation and myelination by oligodendrocytes, the myelinating cells of the CNS. They demonstrate that PAK1 promotes oligodendrocyte differentiation and myelination by modulating the cytoskeleton and thereby internode length, thus playing a critical role in the function of the CNS.     

Morphometric analysis of spike-wave complexes (SWCs) causing myoclonic seizures in children with idiopathic myoclonic epilepsies – A positive SWC component correlates with myoclonic intensity

AimTo elucidate the morphological characteristics of spike-wave complexes (SWCs) causing myoclonic seizures (MS) in childhood-onset idiopathic myoclonic epilepsies.Subjects and MethodsThe subjects were 8 patients, including 4 with epilepsy with myoclonic-atonic seizures (EMAS), 3 with myoclonic epilepsy in infancy (MEI) and 1 with idiopathic unclassifiable myoclonic epilepsy. Morphometric parameters of the SWCs were compared between those with MS [SWC-MS (+)] and those without MS [SWC-MS (-)], and a correlation coefficient analysis was performed between the SWC parameters and the duration of myoclonic electromyogram (EMG) potentials.ResultsA total of 155 SWC-MS (+) (range: 7 ～ 34) and 80 SWC-MS (-) (10 each as a control) were analyzed. Comparison of the parameters of the SWCs between SWC-MS (+) and SWC-MS (-) demonstrated that the depth and the width of the positive-sharp-components (PSC) in the SWC-MS (+) were significantly deeper in amplitude and longer in duration than those in the SWC-MS (-), respectively, in all 8 patients (P < 0.05), whereas the number of the polyphasic-multiple-spike-components (PMSC) and the height of negative-spike-components (NSC) were not significantly different in most of the patients, respectively. The depth and the width of PSC were also significantly correlated with the duration of myoclonic EMG potentials in all patients except one [depth of PSC (n = 7): r = 0.623 ～ 0.888; width of PSC (n = 8): r = 0.676 ～ 0.948, P < 0.05].ConclusionsThis study revealed that the depth and width of PSC of the SWC are positively correlated with the MS intensity in childhood-onset idiopathic myoclonic epilepsies and are an important neurophysiological marker to generate MS.     

Gastric adenocarcinoma of the fundic gland type shares common genetic and phenotypic features with pyloric gland adenoma

Gastric adenocarcinoma of the fundic gland type (GAFG) and pyloric gland adenoma (PGA) have recently been recognized as rare types of neoplasia. We performed comparative immunohistochemical and genetic analyses of 3 GAFGs and 12 PGAs. All of the 3 GAFGs were diffusely positive for pepsinogen‐I, MIST1 and MUC6, indicating the predominantly chief cell/mucous neck cell differentiation of these tumors. A small number of H.K‐ATPase‐positive parietal cells were also scattered. PGAs invariably exhibited diffuse MUC6 and TFF2 expression, consistent with the pyloric gland differentiation of these tumors. Ten of the 12 PGAs also unexpectedly exhibited focal expression of pepsinogen‐I and MIST1, suggesting that PGAs often show focal chief cell differentiation and phenotypically resemble mucous neck cells rather than pyloric glands. The mutation analyses revealed activating GNAS mutations, which have been reported to be frequently detected in PGAs, in two of the GAFGs. While GAFGs and PGAs are morphologically distinct lesions, our observations showed their partially overlapping immunohistochemical profiles and shared presence of GNAS mutations, in addition to their common occurrence in the fundic gland mucosa. Based on these observations, we suggest that both GAFGs and PGAs are closely related lesions characterized by a mucous neck cell/chief cell lineage phenotype.     

Does time of CCI measurement affect the evaluation of platelet transfusion effectiveness?

The measurement of corrected count increment at 1-h post-transfusion (CCI-1 h) of platelet concentrate (PC) transfusion is recommended, but in the revised Japanese Guideline (2017) it was changed to “after 10-min to 1-h”, following the revision of the guidelines from Western countries. Here, we aimed to investigate on the feasibility to apply the CCI measured at 10-min or 30-min post-transfusion as the surrogate of CCI-1 h. Peripheral blood was collected at 10-min, 30-min and 1-h post-transfusion of PC and the effectiveness of the transfusion was analyzed based on the CCI. In the period from December 2017 to February 2020, 8 patients, who received multiple PC transfusion (total 208) at our institution, were analyzed. We performed the univariate analyses to examine the relationship between CCI value and the categorical variables, p-value <0.1 was obtained for gender (p = 2.91 × 10^?19), fever after transfusion (p = 0.0163). The qualitative variables, namely measurement time (p = 0.0553), also showed p-value <0.1. Using these factors as covariates in the mixed effect model, we found that the measurement time (p = 0.0007) had a significant effect on the CCI value when looking at fixed effects. Although there is a tendency for decreased CCI values with time progression, the slope of the change in the mixed model was -0.00307, indicating that the CCI difference among the 3 measurements was small. Here we provide evidence that CCI measured at 10-min and 30-min post-transfusion give results comparable to those measured at 1-h post-transfusion, under the Japanese practice of platelet transfusion, which relies on 100 % single-donor apheresis PC, and ABO-identical whenever possible.     

The combination of ITS2 and psbA-trnH region is powerful DNA barcode markers for authentication of medicinal Terminalia plants from Thailand

Journal of Natural Medicines - The dried fruits of Terminalia plant (Combretaceae) called “Samo” have been used as herbal medicine in Thai traditional medicine. Four “Samo”...