A study of PVRL1 mutations for non-syndromic cleft lip and/or palate among Taiwanese patients.

Mutations of codons 185 and 323, especially the W185X mutation, of the PVRL1 gene among non-syndromic cleft lip and/or palate (CL/P) patients and normal controls in Taiwan were studied in order to determine whether there are mutations that play a part in the formation of non-syndromic CL/P. A total of 76 patients were enrolled; 66 sporadic non-syndromic CL/P patients and 10 normal controls. The mutation survey for codons 185 and 323 was conducted using a polymerase chain reaction and DNA sequencing. Neither mutations of codons 185 and 323 were noted for any of the 76 patients (152 alleles), nor were found any other mutations in either exon 3 or 5 of the PVRL1 gene. These results suggest that mutations of the PVRL1 gene at codons 185 and 323, especially the W185X mutation, do not participate in the formation of CL/P within the Taiwanese population examined.

Retinoblastoma protein (pRB) was significantly phosphorylated through a Ras-to-MAPK pathway in mutant K-ras stably transfected human adrenocortical cells.

Our previous studies have shown that the cell proliferation rate, mRNA levels of p450scc, p450c17, and 3betaHSD, and secretion of cortisol were significantly increased in human adrenocortical cells stably transfected with mutated K-ras expression plasmid "pK568MRSV" after being inducted with IPTG. In addition, the increased level was a time-dependent manner. However, the levels of p450, p450scc, p450c17, 3betaHSD, cortisol, and cell proliferation rate were inhibited by a MEK phospholation inhibitor, PD098059. The above results prove that mutated K-ras oncogene is able to regulate tumorigenesis and steroidogenesis through a Ras-RAF-MEK-MAPK signal transduction pathway. The aim of this study was to investigate regulated factors in this pathway and also examine whether the other signal transduction pathways or other moles involved in tumorigenesis or steroidogenesis. In the first year, we analyzed gene profiles of mutant K-ras-transfected adrenocortical cells by DNA microarray to determine the gene expression related to cell cycle, signal transduction, apoptosis, tumorigenesis, steroidogenesis, and other expressed sequence tag. After being affected by the K-ras mutant, gene expression was significantly increased in some upregulated genes. Human zinc-finger protein 22 increased by 28.5 times, Osteopontin increased by 5.8 times, LIM domain Kinase 2 (LIMK2) increased by 3.3 times, Homo sapiens dual-specificity tyrosine-(Y)-phosphorylation regulated Kinase 2 (DYRK2) increased by 2.2 times, and human syntaxin 3 increased by two times. On the other hand, significant decreases in gene expression were also observed in some downregulated genes. Retinoblastoma binding protein 1 (RBBP1) decreased by four times, Homo sapiens craniofacial development protein 1 (CFDP1) decreased by 2.4 times, DAP Kinase-related apoptosis-inducing protein Kinase 1 (DRAK1) decreased by 2.3 times, SKI-interacting protein (SKIP) decreased by 2.2 times, and human poly(A)-Binding protein (PABP) decreased by 2.1 times. In all significant differentially expressed genes, preliminary analysis by bioinformatics revealed that after induced K-ras mutant expression by isopropyl thiogalctoside (IPTG), the downregulation of RBBP1 gene was most correlated to cell proliferation. RBBP1 can bind with RB/E2F to form a mSIN3-HDAC complex, which induces cell cycle arrest in the G1/G0 stage by repressing transcription of E2F-regulated genes. The result of a Northern blot showed that RBBP1 were inhibited after an induction of IPTG for 36 h. Another Northern blot analysis proved that mRNA levels of cyclin D1 and c-myc increased in proportion to K-ras expression. Finally, Western blot was carried out, and the results showed that phosphorylated pRB also increased. Taken together, we infer that the mutant K-ras oncogene promoted the cells to proceed to the G1/S stage by the inhibiting the formation of RB/RBBP1-dependent repressor complex from binding with the SIN3-HDAC complex, which resulted in the acetylation of histone to active transcription of E2F-regulated genes. However, the roles of the other differentially expressed genes involved in cell proliferation, cell morphologic change, tumorigenesis, or steroidogenesis still need further investigation.

Surgical treatment for rectal prolapse.

BACKGROUND: The problem of full-thickness rectal prolapse is formidable, with no clear predominant treatment of choice. Several operations have been proposed to correct rectal prolapse which can be divided into transabdominal and perineal procedures. METHODS: From September 1982 to October 1999, 32 patients with rectal prolapse were treated with surgical procedures. There were 16 males and 16 females with a mean age of 58.3 years (Range 17-89). Forteen patients received rectopexy procedure, 6 patients received sigmoidectomy, 6 patients received perineal rectosigmoidectomy, 1 patient received Delorme procedure, 1 patient received Thiersch procedure and 4 patients received laparoscopic-assisted sigmoidectomy. The median follow up times were 7.5 years. RESULTS: In the rectopexy group, complication occurred in one patient (7.1%) and one patient recurred (7.1%). In the sigmoidectomy group, there were no complication but one patient recurred (10%). In the perineal rectosigmoidectomy group, there were no complication, but one patient recurred (16.7%). The total complication rate were 3.1% and total recurrence rate were 9.3%. CONCLUSIONS: Although, the best operation for rectal prolapse remains a controversial subject, we believe that laparoscopic-assisted sigmoidectomy offers a promising new option for the treatment of rectal prolapse.

Vibrio aerogenes sp. nov., a facultatively anaerobic marine bacterium that ferments glucose with gas production.

A mesophilic, facultatively anaerobic, marine bacterium, designated strain FG1T, was isolated from a seagrass bed sediment sample collected from Nanwan Bay, Kenting National Park, Taiwan. Cells grown in broth cultures were motile, Gram-negative rods; motility was normally achieved by two sheathed flagella at one pole of the cell. Strain FG1T required Na+ for growth, and exhibited optimal growth at 30-35 degrees C, pH 6-7 and about 4% NaCl. It grew anaerobically by fermenting glucose and other carbohydrates with production of various organic acids, including acetate, lactate, formate, malate, oxaloacetate, propionate, pyruvate and succinate, and the gases CO2 and H2. The strain did not require either vitamins or other organic growth factors for growth. Its DNA G+C content was 45.9 mol%. It contained C12:0 as the most abundant cellular fatty acid. Characterization data, together with the results of a 16S rDNA-based phylogenetic analysis, indicate that strain FG1T represents a new species of the genus Vibrio. Thus, the name Vibrio aerogenes sp. nov. is proposed for this new bacterium. The type strain is FG1T (= ATCC 700797T = CCRC 17041T).

Expression of the mucosal vascular addressin, MAdCAM-1, in inflammatory liver disease.

AIMS/BACKGROUND: The integrin alpha4beta7 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are involved in normal recirculation of lymphocytes between the blood and the tissues of the gastrointestinal tract. In this study we have examined the expression of MAdCAM-1 in human liver. METHODS: MAdCAM-1 expression was determined in archival human liver tissues by immunohistochemistry. RESULTS: While MAdCAM-1 was not detected in normal fetal or adult human liver, expression was observed in association with portal tract inflammation in a variety of liver diseases. Detailed analysis of liver biopsies from patients with hepatitis C showed a positive correlation between the portal/periportal component of the histological activity index (HAI) grade and the presence or absence of MAdCAM-1 expression. CONCLUSION: MAdCAM-1 expression may be important in the recruitment of lymphocytes to the liver during inflammation.

Mononucleosis syndrome and coincidental human herpesvirus-7 and Epstein-Barr virus infection.

Two girls (a 5 year old and a 21 month old) experiencing mononucleosis syndrome with coincidental human herpesvirus (HHV)-7 and Epstein-Barr virus (EBV) infections are described. One patient had primary HHV-7 infection and reactivated EBV infection. The other had primary HHV-7 and EBV infections. These cases indicated that HHV-7 is capable of inducing infectious mononucleosis-like illness. Multiple herpesvirus infection in one of the patients also suggests that interaction among herpesviruses can occur in vivo. The consequence of this interaction may have clinical implications.

Bacteremia and fungemia in hematological and oncological children with neutropenic fever: two-year study in a medical center.

A retrospective study of bacteremia in children with neutropenic fever admitted to a medical center in Taiwan from Jan. 1994 to Dec. 1995 was performed. There were in total 273 episodes of neutropenic fever during this period, but only 79 pathogens were isolated from blood specimens in 70 episodes. Klebsiella pneumoniae (27.8%), E. coli (10.1%), Staphylococcus aureus (10.1%) and Pseudomonas aeruginosa (7.6%) were the most common pathogens. All the isolates of S. aureus were methicillin sensitive. About half of K. pneumoniae (10/22) was multiple-drug resistant. There were seven infection-related mortality cases, three due to multiple-drug resistant K. pneumoniae, one due to S. aureus, one alpha-hemolytic streptococcus and two fungemia (Cryptococcus neoformans and Fusarium sp.). Vancomycin is not necessary in initial empiric therapy of neutropenic fever, while cefazolin or oxacillin may be included in cases with central venous access device. Antibiotics to cover intestinal flora, especially K. pneumoniae, are paramount in our hospital.

Seroepidemiological study of measles after the 1992 nationwide MMR revaccination program in Taiwan.

The incidence of measles declined rapidly in Taiwan after the introduction of the measles vaccine into the routine immunization schedule in 1978. However, an epidemic still occurred every 3-5 years until recently. A nationwide measles-mumps-rubella (MMR) revaccination program for school and preschool children has been in place since 1992 to control the indigenous transmission of measles. In order to understand the current immune status after this recent nationwide revaccination program, we determined the presence of measles IgG antibodies by enzyme-linked immunosorbent assay (ELISA) in 1,281 blood samples from healthy persons aged from 2 months to above 30 years collected between 1993 and 1995, and also in another batch of 90 sera samples from children aged 2 years collected before 1992. The results showed that 1) the measles antibody seropositive rate (36.4%) was lowest in children aged 5-7 months and rose to an unexpectedly high level of 85.8% at the age of 12-14 months, 2) the seropositive rate rose further to between 85.9% and 95.1% after 2 years of age and remained high in adults and pregnant women, and 3) the seropositive rate of the 2-year-old children collected before 1992 was 61.4%, which was significantly lower than the rate of the same age group collected after the nationwide MMR revaccination program. We conclude that the national revaccination program has promoted effectively measles immunity in Taiwan. This immunity explains the rarity of reported measles cases since the last epidemic in 1989. This revaccination program should continue and be extended to all preschool children and young adults so that indigenous measles can be eliminated by the year 2000.

Mucosal addressin cell adhesion molecule-1: a structural and functional analysis demarcates the integrin binding motif.

The leukocyte integrin receptor, alpha 4 beta 7, and the mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are postulated to be important in regulating lymphocyte trafficking to normal intestine. Here we provide the first description of MAdCAM-1 expression in inflamed intestine. Using mouse models of experimentally induced colitis, we show a concordant increase in MAdCAM-1 expression associated with increased cellular infiltrates in areas of intestinal inflammation. To understand more of the molecular nature of the interactions between MAdCAM-1 and its leukocyte ligand, the alpha 4 beta 7 integrin receptor, we have analyzed the structural and functional properties of chimeric recombinant MAdCAM-1 proteins in vitro. Using site-directed mutagenesis and molecular modeling, we demarcate the alpha 4 beta 7 binding motif as three linear residues within the C-D loop in the first domain of MAdCAM-1. Mutation of residue L40, D41, or T42 in the first domain completely abrogates alpha 4 beta 7+ cell binding and cellular activation. Mutagenesis of other residues in the first domain do not impact these functions. We have modeled peptides based on the predicted structure of the alpha 4 beta 7 integrin binding motif on MAdCAM-1 and are able to show specific and selective blocking of cell binding. These observations suggest that the amino acid residues LDT on MAdCAM-1 play a role in the interaction with alpha 4 beta 7 in cell adherence and cell activation.