[Clinicopathological analysis of mucosa associated lymphoid tissue lymphoma secondary to Sjögren' s syndrome in salivary gland].

OBJECTIVE: To analyze the clinicopathological characteristics of mucosa associated lymphoid tissue (MALT) lymphoma secondary to Sjögren' s syndrome (SS) (SS-MALT lymphoma) in salivary gland and to explore the value of the combined application of histopathological morphology, protein expression and molecular phenotype in pathological diagnosis and prognostic evaluation of SS-MALT lymphoma. METHODS: Sixteen patients with SS-MALT lymphoma were collected from 260 patients who were diagnosed with SS in Peking University School and Hospital of Stomatology from January 1997 to December 2016. Twelve patients with non-MALT lymphoma secondary to SS (non-SS-MALT lymphoma) in salivary gland were selected as controls. The clinical data of the patients were retrospectively reviewed and analyzed. All the patients were followed up until December 20, 2019. Hematoxylin-eosin staining, immunohistochemistry, polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH) techniques were used to observe the histologic characteristics and to detect the manifestations of light chain restrictive expression, immunoglobulin (Ig) gene clonal rearrangement, chromosome translocation and gene abnormality, so as to evaluate their values in pathological diagnosis and prognostic evaluation. RESULTS: The malignant transformation rate of SS to MALT lymphoma was about 6.15%, ranged from 3 to 240 months, during which 2 patients died due to high-level deterioration. Microscopically, the acini of the glandular tissue were atrophied and destroyed. The tumor cells dominated by central cell-like lymphocytes grew diffusely, destroying the epithelial islands. All SS-MALT lymphoma cases were positive in CD20 and Pax5. Half of them had the Ki-67 proliferation index of 10% or less, and half greater than 10%. 93.75% cases expressed AE1/AE3 protein, which showed the residual glandular epithelium. All the tumor cells were negative in CD3ε, and the plasma cells were detected by CD138 antigen. The light chain restrictive expression of κ and λ was 37.5% in SS-MALT lymphoma group. The positive detection rates of immunoglobulin heavy chain (IgH)-FR1, IgH-FR2, IgH-FR3, immunoglobulin kappa chain (IgK)-A, and IgK-B in SS-MALT lymphoma group were 33.3%, 53.3%, 33.3%, 20.0%, and 26.7%, respectively, and 93.3% when together used with IgH and IgK. The positive rates of the MALT1, IGH and BCL6 genes with dual color break-apart probes were 36.4%, 27.3% and 27.3%, and the detection rate of chromosome translocation and gene abnormality by applying the three probes was 72.7%. CONCLUSION: There are no specific histological characteristics and protein phenotypes in the histologic diagnosis of SS-MALT lymphoma in salivary gland. The combined application of histopathological manifestations, immunohistochemistry, PCR and FISH techniques helps the accurate pathologic diagnosis of the disease. Although SS-MALT lymphoma is considered as an indolent lymphoma with a relatively favorable prognosis, the regular return visit and long-term follow-up should be conducted to detect the clues of recurrence and advanced deterioration.

Association between the interleukin-1ß C-511T polymorphism and periodontitis: a meta-analysis in the Chinese population.

The association between the interleukin-1 beta (IL-1ß) C-511T (or rs16944) polymorphism and periodontitis remains inconclusive, even though there have been previous studies on this association. To assess the effects of IL-1ß C-511T variants on the risk of development of periodontitis, a meta-analysis was performed in a single ethnic population. Studies, published up to December 2015, were selected for the meta-analysis from PubMed and Chinese databases. The associations were assessed with pooled OR and 95%CI. This meta-analysis identified 8 studies, including 1276 periodontitis cases and 1558 controls. Overall, a significant association between the IL-1ß C-511T polymorphism and periodontitis was found in the Chinese population (TT vs CC: OR = 1.48, 95%CI = 1.19-1.85; TT + CT vs CC: OR = 1.50, 95%CI = 1.25-1.81; T vs C: OR = 1.33, 95%CI = 1.06-1.68). In the subgroup analyses based on geographical area(s), source of controls, and type of periodontitis, significant results were obtained for the association between IL-1ß C-511T variants and periodontitis. Our meta-analysis indicated that the IL-1ß C-511T polymorphism may be a genetic susceptibility factor for periodontitis in the Chinese population. This marker could be used to identify Chinese individuals at a high risk for periodontitis.

[Expression of secreted frizzled-related protein-1 in patient with oral submucous fibrosis].

Objective: To investigate the concentrations and clinical significance of secreted frizzled-related protein-1(SFRP1) insaliva and gingival crevicular fluid of patients with oral submucous fibrosis (OSF) as well as the expression of SFRP1 in patients' OSF buccal mucosa. Methods: Twenty OSF patients aged 20 to 40 years old were recruited and randomly divided into two experimental groups, of which were triamcinolone acetonide group and combined triamcinolone acetonide and salvia miltiorrhiza group, respectively. Ten healthy volunteers matchable in sex and age with the patients were recruited as control group. Concentrations of SFRP1 in saliva and gingival crevicular fluid were detected by enzyme-linked immunosorbent assay before and after a continuous treatment of 4 weeks. The visual analogue scale(VAS) pain scores and opening size were also recorded. The expression of SFRP1 in samples from OSF patients' buccal mucosa was also detected using immunohistochemical method. SPSS 16.0 was applied to analyze the results of the experiments. Results: The concentrations of SFRP1 in saliva and gingival crevicular fluid before treatment were (105.8±27.6) ng/L and (84.7±33.2) ng/L in triamcinolone acetonide group, and (86.6±23.2) ng/L and (97.0±23.2) ng/L in combining group, which were both significantly lower(P<0.01) than that in normal group([153.0±32.8] ng/L and [157.5±31.1] ng/L), respectively. The positive expression rate of SFRP1 in OSF group(10%[2/20]) was significantly lower than that of the control group(10/10)(P<0.01). After the treatment for 4 weeks, the concentrations of SFRP1 increased to (141.2±35.3) ng/L and (130.6±31.3) ng/L in triamcinolone acetonide group, and to (148.5±65.9) ng/L and (123.0±27.4) ng/L in combining group, which were both significantly higher than those of pre-treatment, respectively(P<0.01). Conclusions: The concentrations of SFRP1 in saliva and gingival crevicular fluid of OSF patients, which positively corelated to the expression of SFRP1 in OSF patients' buccal mucosa, were significantly lower than that of normal individuals and increased significantly after treatments of local injections of triamcinolone acetonide only or combined with salvia miltiorrhiza.

Purification and characterization of a lipopeptide produced by Bacillus thuringiensis CMB26.

AIMS: To isolate an antagonist for use in the biological control of phytopathogenic fungi including Colletotrichum gloeosporioides, then to purify and characterize the biocontrol agent produced by the antagonist. METHODS AND RESULTS: Bacteria that exhibited antifungal activity against the causative agent pepper anthracnose were isolated from soil, with Bacillus thuringiensis CMB26 showing the strongest activity. A lipopeptide produced by B. thuringiensis CMB26 was precipitated by adjusting the pH 2 with 3 n HCl and extracted using chloroform/methanol (2:1, v/v) and reversed-phase HPLC. The molecular weight was estimated as 1447 Da by MALDI-TOF mass spectrometry. Scanning electron and optical microscopies showed that the lipopeptide has activity against Escherichia coli O157:ac88, larvae of the cabbage white butterfly (Pieris rapae crucivora) and phytopathogenic fungi. The lipopeptide had cyclic structure and the amino acid composition was L-Glu, D-Orn, L-Tyr, D-allo-Thr, D-Ala, D-Val, L-Pro, and L-Ile in a molar ratio of 3:1:2:1:1:2:1:1. The purified lipopeptide showed the same amino acid composition as fengycin, but differed slightly in fatty acid composition, in which the double bond was at carbons 13-14 (m/z 303, 316) and there was no methyl group. CONCLUSION: A lipopeptide was purified and characterized from B. thuringiensis CMB26 and found to be similar to the lipopeptide fengycin. This lipopeptide can function as a biocontrol agent, and exhibits fungicidal, bactericidal, and insecticidal activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Compared with surfactin and iturin, the lipopeptide from B. thuringiensis CMB26 showed stronger antifungal activity against phytopathogenic fungi. This lipopeptide is a candidate for the biocontrol of pathogens in agriculture.

Characterization of two cDNA clones for pyruvate dehydrogenase E1 beta subunit and its regulation in tricarboxylic acid cycle-deficient fibroblast.

Two distinct types of cDNA clones encoding for the pyruvate dehydrogenase (PDH) E1 beta subunit were isolated from a human liver lambda gt11 cDNA library and characterized. These cDNA clones have identical nucleotide sequences for PDH E1 beta protein coding region but differ in their lengths and in the sequences of their 3'-untranslated regions. The smaller cDNA had an unusual polyadenylation signal within its protein coding region. The cDNA-deduced protein of PDH E1 beta subunit revealed a precursor protein of 359 amino acid residues (Mr 39,223) and a mature protein of 329 residues (Mr 35,894), respectively. Both cDNAs shared high amino acid sequence similarity with that isolated from human foreskin (Koike, K.K., Ohta, S., Urata, Y., Kagawa, Y., and Koike, M. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 41-45) except for three regions of frameshift mutation. These changes led to dramatic alterations in the local net charges and predicted protein conformation. One of the different sequences in the protein coding region of liver cDNA (nucleotide position 452-752) reported here was confirmed by sequencing the region after amplification of cDNA prepared from human skin fibroblasts by the polymerase chain reaction. Southern blot analysis verified simple patterns of hybridization with E1 beta cDNA, indicating that the PDH E1 beta subunit gene is not a member of a multigene family. The mechanisms of differential expression of the PDH E1 alpha and E1 beta subunits were also studied in established fibroblast cell lines obtained from patients with Leigh's syndrome and other forms of congenital lactic acidosis. In Northern blot analyses for PDH E1 alpha and E1 beta subunits, no apparent differences were observed between two Leigh's syndrome and the control fibroblasts studied: one species of PDH E1 alpha mRNA and three species of E1 beta mRNA were observed in all the cell lines examined. However, in one tricarboxylic acid cycle deficient fibroblast cell line, which has one-tenth of the normal enzyme activity, the levels of immunoreactive PDH E1 alpha and E1 beta subunits were markedly decreased as assessed by immunoblot analyses. These data indicated a regulatory mutation caused by either inefficient translation of E1 alpha and E1 beta mRNAs into protein or rapid degradation of both subunits upon translation. In contrast, the PDH E1 alpha and E1 beta subunits in two fibroblast cell lines from Leigh's syndrome patients appeared to be normal as judged by 1) enzyme activity, 2) mRNA Northern blot, 3) genomic DNA Southern blot, and 4) immunoblot analyses indicating that the lactic acidosis seen in these patients did not result from a single defect in either of these E1 alpha and E1 beta subunits of the PDH complex.

Three genes for enzymes of the pyruvate dehydrogenase complex map to human chromosomes 3, 7, and X.

The genes for three proteins of the pyruvate dehydrogenase (PDH) complex have been assigned to human chromosomes by Southern analysis of a panel of human-rodent somatic cell hybrid DNAs with cDNA probes for these genes. PDH-E1 alpha has been localized on human chromosome 3p13-q23. The assignments of lipoamide dehydrogenase(E3) and PDH-E1 alpha [corrected] to chromosomes 7 and Xp, respectively, have been confirmed. Restrictive-fragment-length polymorphisms have been identified with E3, which will permit further localization of this gene by genetic linkage analysis.