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PubMed1981

Extraskeletal myxoid chondrosarcoma--a clinicopathologic and electron microscopic study.

This clinicopathologic study concerns 14 cases of extraskeletal myxoid chondrosarcoma from among 603 cases of soft tissue sarcomas. The ages of the patients at the time of initial biopsy ranged from 16 to 69 years. The tumors mainly arose in the lower extremities including buttocks (10 cases), and consisted histologically in cords and strands of small acidophilic cells with occasional vacuolated cells in an abundant myxoid matrix composed of chondroitin sulfate. Electron microscopy in four revealed a continuum of cell differentiation of the tumor cells from chondroblastic cell to undifferentiated mesenchymal cell. Morphological studies indicated that the extraskeletal myxoid chondrosarcoma included so-called chordoid sarcoma, as a variant.

Adolescent↗
PubMed2004

Two novel ADAMTS13 gene mutations in thrombotic thrombocytopenic purpura/hemolytic-uremic syndrome (TTP/HUS).

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) and hemolytic-uremic syndrome (HUS) are now considered to be variants of one single syndrome called thrombotic thrombocytopenic purpura/hemolytic-uremic syndrome (TTP/HUS). Key features are thrombocytopenia, hemolytic anemia, and subsequently impaired function of different organs, especially the kidneys and the central nervous system (CNS). One possible reason is the deficiency of von Willebrand factor-cleaving protease (vWF-CP) resulting in persistence of uncleaved, ultralarge von Willebrand factor multimers (ULvWFM). METHODS: We report a patient who was initially diagnosed with Evans syndrome (hemolytic anemia and autoimmune thrombocytopenia) as infant. At 10 years of age he developed HUS-like disease with gastrointestinal tract infection, hemolytic anemia, thrombocytopenia,and acute renal failure. However, enteropathogenic Escherichia coli-like or Shiga-like toxins were not detected. RESULTS: Further investigations revealed severe deficiency (<3%; normal >40%) of vWF-CP activity caused by compound heterozygosity of two novel ADAMTS13 gene mutations (1170 G>C [W390C] and 3735 G>A [W1245X]. vWF-CP autoantibodies were not detected. Periodic (every 2 weeks) treatment with fresh frozen plasma (FFP) maintained both platelet level and kidney function within normal range and prevented new episodes of TTP/HUS. CONCLUSION: Enteropathogenic E. coli- and Shiga-like toxin-negative patients who present with hemolytic or thrombocytopenic episodes and HUS like symptoms should be tested for vWF-CP deficiency and other noninfectious reasons for TTP/HUS since plasma substitution possibly provides an efficient therapeutic option for this subgroup of patients.

ADAM Proteins↗
PubMed2006

Variant Salmonella genomic island 1-L antibiotic resistance gene cluster in Salmonella enterica serovar Newport.

We report a new Salmonella genomic island 1 variant antibiotic resistance gene cluster called SGI1-L in a Salmonella enterica serovar Newport isolate containing a dfrA15 gene cassette conferring resistance to trimethoprim. The isolate carried another class 1 integron containing the aacC5 and aadA7 gene cassettes conferring resistance to gentamicin and streptomycin/spectinomycin, respectively.

Anti-Bacterial Agents↗
PubMed1996

Vaccination with genetically modified Shiga-like toxin IIe prevents edema disease in swine.

Escherichia coli strains producing Shiga-like toxin II variant (SLT-IIe, formerly called SLT-IIv) cause edema disease in weaned pigs. Vaccination of pigs with a genetically modified form of Shiga-like toxin IIe, SLT-IIe(E167Q), has been previously shown to be nontoxic and to induce antibodies to SLT-IIe (V.M. Gordon. S.C. Whipp, H.W. Moon, A.D. O'Brien, and J.E. Samuel, Infect, Immun. 60:485-502, 1992). Fifty micrograms of SLT-IIe(E167Q) toxin was used to vaccinate suckling pigs at 1 and 2 weeks of age. Both vaccinated and nonvaccinated pigs were orally inoculated with an SLT-IIe-producing strain of E. coli after weaning (3 to 4 weeks of age). Pigs fed a low-protein diet that were not vaccinated with SLT-IIe(E167Q) developed subclinical edema disease, histologically evident as vascular necrosis. Pigs fed a high-protein diet that were not vaccinated with SLT-IIe(E167Q) developed clinical edema disease manifested as vascular necrosis, reduced weight gain, ataxia, palpebral edema, lateral recumbency, and death. Pigs vaccinated with SLT-IIe(E167Q) had a reduction in the incidence of subclinical edema disease and never developed clinical edema disease. These data demonstrate that vaccination with a genetically modified form of SLT-IIe prevents edema disease and are consistent with the notion that diet influences susceptibility to edema disease.

Animals↗
PubMed1998

Phase variation in Helicobacter pylori lipopolysaccharide.

Helicobacter pylori NCTC 11637 lipopolysaccharide (LPS) expresses the human blood group antigen Lewis x (Le(x)) in a polymeric form. Le(x) is beta-D-galactose-(1-4)-[alpha-L-fucose-(1-3)]-beta-D-acetylglucosamine. Schematically the LPS structure is (Le(x))n-core-lipid A. In this report, we show that Le(x) expression is not a stable trait but that LPS displays a high frequency (0.2 to 0.5%) of phase variation, resulting in the presence of several LPS variants in one bacterial cell population. One type of phase variation implied the loss of alpha1,3-linked fucose, resulting in variants that expressed nonsubstituted polylactosamines (also called the i antigen), i.e., Le(x) minus fucose; LPS: (lactosamine)n-core-lipid A. The switch of Le(x) to i antigen was reversible. A second group of variants arose by loss of polymeric main chain which resulted in expression of monomeric Le(y); LPS: (Le(y))-core-lipid A. A third group of variants arose by acquisition of alpha1,2-linked fucose which hence expressed Le(x) plus Le(y); LPS: (Le(y))(Le(x))n-core-lipid A. The second and third group of variants switched back to the parental phenotype [(Le(x))-core-lipid A] in lower frequencies. Part of the variation can be ascribed to altered expression levels of glycosyltransferase levels as assessed by assaying the activities of galactosyl-, fucosyl-, and N-acetylglucosaminyltransferases. Clearly phase variation increases the heterogeneity of H. pylori, and this process may be involved in generating the very closely related yet genetically slightly different strains that have been isolated from one patient.

Amino Sugars↗
PubMed1997

Sequencing of heat shock protein 70 (DnaK) homologs from Deinococcus proteolyticus and Thermomicrobium roseum and their integration in a protein-based phylogeny of prokaryotes.

The 70-kDa heat shock protein (hsp70) sequences define one of the most conserved proteins known to date. The hsp70 genes from Deinococcus proteolyticus and Thermomicrobium roseum, which were chosen as representatives of two of the most deeply branching divisions in the 16S rRNA trees, were cloned and sequenced. hsp70 from both these species as well as Thermus aquaticus contained a large insert in the N-terminal quadrant, which has been observed before as a unique characteristic of gram-negative eubacteria and eukaryotes and is not found in any gram-positive bacteria or archaebacteria. Phylogenetic analysis of hsp70 sequences shows that all of the gram-negative eubacterial species examined to date (which includes members from the genera Deinococcus and Thermus, green nonsulfur bacteria, cyanobacteria, chlamydiae, spirochetes, and alpha-, beta-, and gamma-subdivisions of proteobacteria) form a monophyletic group (excluding eukaryotic homologs which are derived from this group via endosybitic means) strongly supported by the bootstrap scores. A closer affinity of the Deinococcus and Thermus species to the cyanobacteria than to the other available gram-negative sequences is also observed in the present work. In the hsp7O trees, D. proteolyticus and T. aquaticus were found to be the most deeply branching species within the gram-negative eubacteria. The hsp70 homologs from gram-positive bacteria branched separately from gram-negative bacteria and exhibited a closer relationship to and shared sequence signatures with the archaebacteria. A polyphyletic branching of archaebacteria within gram-positive bacteria is strongly favored by different phylogenetic methods. These observations differ from the rRNA-based phylogenies where both gram-negative and gram-positive species are indicated to be polyphyletic. While it remains unclear whether parts of the genome may have variant evolutionary histories, these results call into question the general validity of the currently favored three-domain dogma.

Amino Acid Sequence↗
PubMed2004

Rapid quantification of Yersinia enterocolitica in pork samples by a novel sample preparation method, flotation, prior to real-time PCR.

The development of real-time PCR thermal cycles in the late 1990s has opened up the possibility of accurate quantification of microorganisms in clinical, environmental, and food samples. However, a lack of suitable sample preparation methods that allow rapid quantification of the nucleic acids, remove PCR inhibitors, and prevent false-positive results due to DNA originating from dead cells has limited the use of quantitative PCR. We have used for the first time a new variant of density gradient centrifugation, called flotation, as a user-friendly sample preparation method prior to PCR. This paper describes the use of this sample preparation method, without DNA purification, for direct detection and quantification of Yersinia enterocolitica in PCR-inhibitory meat juice from pork. Flotation combined with qPCR could overcome PCR interference in juice from pork, as was shown by amplification efficiencies of 1.006 +/- 0.021 and 1.007 +/- 0.025, which are comparable to the amplification efficiency obtained for purified DNA samples (1.005 +/- 0.059). Applying flotation to meat juice samples containing natural background flora and spiked with different levels of Y. enterocolitica showed that direct quantification of Y. enterocolitica was possible down to a level of at least 4.2 x 10(3) CFU per ml of meat juice, even in the presence of 10(6) CFU of background flora per ml. Finally, the results showed that samples containing large amounts of Y. enterocolitica DNA did not result in a positive PCR signal. This indicates that the risk of false-positive results due to detection of DNA originating from dead cells can be greatly reduced by using flotation prior to PCR.

Animals↗
PubMed1973

Mapping of simian virus 40 early functions on the viral chromosome.

The simian virus 40 (SV40) DNA segment in the nondefective adenovirus 2-SV40 hybrid, Ad2(+)ND(4), is colinear with the segment between 0.11 and 0.59 SV40 fractional length from the site at which the R(1) restriction endonuclease cleaves SV40 DNA. This specifies the region of the SV40 DNA molecule which induces the early SV40 antigens: U antigen, tumor specific transplantation antigen, and T antigen. A variant of Ad2(+)ND(4), called Ad2(+)ND(4del), was found which has a deletion of the DNA segment between 0.50 and 0.57 SV40 fractional length from the R(1) endonuclease cleavage point.

Adenoviridae↗
PubMed2005

Basal cell hyperplasia and basal cell carcinoma of the prostate: a comprehensive review and discussion of a case with c-erbB-2 expression.

Prostatic basal cell proliferations range from ordinary basal cell hyperplasia (BCH) to florid basal cell hyperplasia to basal cell carcinoma. The distinction between these forms of BCH, including the variant with prominent nucleoli (formerly called atypical BCH), and basal cell carcinoma depends on morphological and immunohistochemical criteria and, in particular, on the degree of cell proliferation. In florid BCH, the proliferation index is intermediate between ordinary BCH and basal cell carcinoma. Immunohistochemistry is also useful for identifying the cell composition of the basal cell proliferations, including the basal cell nature of the cells, their myoepithelial differentiation, and c-erbB-2 oncoprotein expression. Based on the information derived from the literature and on the appearance and follow up of the case presented here, florid BCH might represent a lesion with an intermediate position between ordinary BCH and basal cell carcinoma. However, criteria useful for the identification of those cases with a true precursor nature are not available. In general, basal cell carcinoma is seen as a low grade carcinoma. The immunohistochemical expression of the c-erbB-2 oncoprotein, similar to that seen in breast cancer, might have therapeutic importance.

Aged↗
PubMed2002

Meyerson phenomenon within a nevus flammeus. The different eczematous reactions within port-wine stains.

Only few reports about eczematous reactions overlying nevi flammei exist. All of them were observed in children. The description of an eczematous reaction within a congenital nevus flammeus on the left lower leg of a male adult gives reason to discuss this rare phenomenon. Eczema or inflammatory changes within a port-wine stain may mostly be a collision dermatosis with an atopic dermatitis, especially when they arise in children and are localized to the neck and face. When they are observed within a grossly visible vascular malformation, as for example in the Klippel-Trenaunay syndrome, they may have a pathogenesis similar to stasis dermatitis. In rare cases, an eczematous reaction within a nevus flammeus may be the result of genetic mosaicism and is interpreted as a variant of the so-called Meyerson phenomenon.

Humans↗
PubMedDate not supplied

Chordomas: nasopharyngeal presentation and atypical long survival.

Atypical clinical and pathological features of a cranio-cervical chordomas have prompted a review of these neoplasms at the University of Michigan Medical Center. Contrary to prior investigations, 92% of the spheno-occipital chordomas reported in this study clinically presented with a nasopharyngeal or intranasal mass. This high incidence indicates the requirement for an otorhinologic examination on all patients presenting with the neuro-ophthalmologic syndrome and roentgenologic findings characteristic of chordomas in this anatomical region. Special attenion is called to a histologically distinctive variant of chordoma - the "chondroid chordoma.' Apparently restricted to the cranio-cervical region, this variant has been associated with long survival.

Adolescent↗
PubMed2006

Colonic and duodenal flat adenomas in children with classical familial adenomatous polyposis.

Flat adenomas of the colon and duodenum have been described as associating with familial adenomatous polyposis (FAP), its attenuated variant, and the so-called hereditary nonpolyposis colorectal cancer. There seem to be no report on the occurrence of flat adenomas in pediatric patients with family history of FAP. We are reporting 4 children from 2 cancer-prone families in whom colonic and duodenal moderately dysplastic flat adenomas were found. Gastrointestinal endoscopy and biopsies were performed in 3 female siblings (7, 9, and 11 years old) and 1 male (9 years old) when referred for screening owing to familial history of bowel cancer (family 1) or evidence of bilateral congenital hypertrophy of the retinal pigment epithelium (CHRPE), which is known to be associated with FAP (family 2). Endoscopic visualization of the mucosa was improved by use of 0.2% indigo carmine solution spray. Biopsies were routinely processed for H&E and immunohistochemistry staining. Present patients were asymptomatic, with the exception of 2 weeks rectal bleeding in 1 of them. The colonic videoendoscopy showed in 2/3 siblings hundreds of flat or slightly raised plaques less than 1 cm in diameter as well as some classic polyps throughout the colon. The other sibling showed 40 flat-topped lesions with minimal elevation and central umbilication in the cecum. Upper endoscopy demonstrated a few flat lesions in the nonperiampullary area of the duodenum in 2/4 patients. The colonic videoendoscopy performed on the 9-year-old boy revealed multiple small sessile polyps. Microscopic study demonstrated tubular adenomas with a few neoplastic crypts, slight disarray of the overall architecture, and moderate (low-grade) dysplasia of the epithelium. These features were more obvious at the center and superficial areas of the adenomas. The 4 children had multiple flat adenomas of the colon and duodenum (2/4) matching with those described in adult patients. Flat adenomas in the context of FAP probably represent early stages of the adenoma development. Careful endoscopic-histologic correlation may result in increasing recognition of these lesions at the pediatric age.

Adenoma↗
PubMed2006

Far eastern tick-borne rickettsiosis: identification of two new cases and tick vector.

We recently reported the first documented cases of a new rickettsial disease caused by Rickettsia heilongjiangensis in the Russian Far East (Far Eastern tick-borne rickettsiosis). Here we report the amplification of DNA of R. heilongjiangensis from both the skin biopsy of an acutely ill patient and the tick removed from him prior to the disease development. The tick has been identified as Haemaphysalis spp. The clinical picture was that of a spotted fever group rickettsiosis and a seroconversion was noted with R. heilongjiangensis antigen. Screening testing of both species of Haemaphysalis ticks inhabiting Russian Far Eastern regions showed that up to 28.13% of H. concinnae and 4.48% of H. japonica douglasii ticks harbor R. heilongjiangensis. It has been concluded that H. concinnae may serve as the main vector for the transmission of R. heilongjiangensis. H. japonica douglasii ticks harbor several varieties of rickettsiae. DNA of "Candidatus Rickettsia tarasevichiae," previously found in Ixodes persulcatus ticks, was amplified from one male tick. Two sequenced complete gltA genes belong to the novel spotted fever group rickettsial species provisionally called here "Candidatus Rickettsia principis" variants Hjd54 and Hjd61. The rate of infection has been found to be not higher than 1.5%.

Adult↗
PubMed2004

Mandibular ramus-related Stafne's bone cavity.

Mandibular bone depressions located on the lingual/buccal aspect of the mandibular ramus are the rarest variants of the so-called Stafne's bone cavities, or major salivary gland-related depressions, with only 17 cases reported in the literature including both clinical cases and archaeological specimens. We report the case of a 14-year-old male patient who sought clinical assistance complaining of a hard expansion on the lower left premolar-molar region. Apart from a unilocular radiolucent lesion between the lower left second premolar and first molar, a panoramic radiograph showed another radiolucent lesion located in the right mandibular ramus, at the level of the mandibular foramen. Computed tomography (CT) revealed an expansile lesion in the left mandibular body, later diagnosed as a simple bone cyst through surgical exploration. The three-dimensional CT volume rendering reconstructed image showed that the second lesion, located on the lingual aspect of the ascending ramus, was an actual cortical bone defect, which was diagnosed as a mandibular ramus-related Stafne's bone cavity. Considering the young age of the patient, the size of the defect, the recognizedly slow development of mandibular bone defects and, above all, the location of the bone defect under discussion, we believe it to have a congenital rather than a developmental origin (i.e. it was caused by a focal failure during intramembranous ossification of the mandible). If this is the case, mandibular bone depressions should not be seen exclusively as salivary gland-related bone defects.

Adolescent↗
PubMed1998

Anaplastic large cell lymphoma: a concept reviewed.

The development of the concept of anaplastic large cell lymphoma is reviewed. The subtypes of the tumor proposed in the literature, including the so-called Hodgkin's-like variant, are discussed both on morphological and clinical grounds. The more recent information on the genetic and molecular characteristics of the tumor (i.e. 2;5 translocation, formation of the NPM/ALK hybrid gene, and production of a specific protein) are presented: their possible implications in the future classification and clinical management of the neoplasm are discussed.

Journal Article↗
PubMed2000

[Thelarche praecox in young girls: recent approaches to the pathogenesis and clinical evaluation].

Premature breast development (premature thelarche) is a common reason of referring prepubertal girls for endocrinological evaluation. It is considered as a benign condition but its pathogenesis is still unknown. It is postulated that it may be due to premature partial activation of hypothalamo-pituitary axis or to the increased sensitivity of breast tissue to normal, prepubertal estradiol levels. Although it rarely progresses to central precocious puberty the differential diagnostics is essential, as the latter pathology should be treated as early as possible. So called "exaggerated thelarche" or "telarche variant" may constitute a diagnostic challenge.

Breast↗
PubMed2005

Differential expression analysis of MIM (MTSS1) splice variants and a functional role of MIM in prostate cancer cell biology.

We previously identified MIM-A (missing in metastasis, MTSS1) by differential display techniques as missing in invasive, metastatic bladder cancer cell lines and suggested that MIM-A is a novel putative metastasis suppressor gene. Characterization of the MIM gene revealed a WH2 (Wiskott-Aldrich syndrome protein homology 2) domain in the C-terminus that is known to bind actin monomers and regulate organization of the actin cytoskeleton. Here, we further describe two alternatively splice variants of MIM-A, called MIM(12del) and MIM-B, which share > 50% amino acid sequence homology with MIM-A in the C-terminal domain. We show that expression of all three transcripts is down-regulated in prostate cancer cell lines and tumor samples from patients. In addition, we generated stably-transfected PC-3 cells overexpressing MIM-A to evaluate the importance of MIM-A in prostate cancer biology. The initial experiments show that expression of MIM decreased the number of actin filaments and was associated with a decrease in the G:F actin ratio. Overexpression of MIM-A had no effect on PC-3 cell adhesion to extracellular matrices, as well as no effect on PC-3 motility. Further, overexpression of MIM-A reduced the rate of PC-3 cell proliferation. These results support the hypothesis that MIM-A is an actin-binding protein and implicate a role of MIM-A in the regulation of cellular proliferation. These data suggest that the reduction of MIM-A gene expression in prostate cancer and other cancers may contribute to tumor growth and development, as well as metastasis.

Actins↗
PubMed1987

Mechanism of leukemogenesis by human T-cell leukemia virus types I and II: role of the lor gene.

The human T-cell leukemia (HTLV) family of viruses now include two groups of transforming viruses (HTLV-I and HTLV-II) and one group of viruses with immunosuppressive activity but no apparent transforming ability (HTLV-III). Nucleotide sequence analysis of an HTLV-I provirus by Seiki et al [Proc Natl Acad Sci USA 1982: 6899-902] has revealed a distinct region of the genome located between env and the long terminal repeat sequences (LTR). Analysis of a variant of HTLV-I, called HTLV-Ib, which retains transforming ability, revealed a deletion in the 5' portion of this sequence that indicates that this portion of the sequence probably does not play an essential role in transformation. Hybridizations at varying stringencies show that at least a portion of this additional region of HTLV-I and -II is more highly conserved than most other regions of the genome. The DNA sequence of this HTLV-II region localizes the area of homology within the 1,000 base pairs just upstream of the LTR; the remainder of the region is not conserved. The conserved region includes a long open reading frame, is denoted lor, and has the coding capacity for a protein of at least 38 kilodaltons (kd). Studies of the transcriptional activity of the LTR sequences show that the rate of LTR-directed transcription is greatly augmented in HTLV-infected cells, a phenomenon called trans-acting transcriptional regulation. It is suggested that transformation of lymphocytes by HTLV-I or -II is mediated by action of HTLV-encoded trans-acting transcription factors on cellular genes that control the replication of lymphocytes.

Deltaretrovirus Infections↗