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PubMed2001

Cerebral and oculorhinal manifestations of a limited form of Wegener's granulomatosis with c-ANCA-associated vasculitis.

The authors report on cerebral and oculorhinal manifestations in a patient with a cytoplasmic pattern of antineutrophil cytoplasmic autoantibody (c-ANCA)-associated vasculitis. Recurrent Tolosa-Hunt syndrome, cavernous sinus syndrome, Raeder's paratrigeminal neuralgia, and seizures were the major clinical manifestations. Brain MRI showed localized enhancing lesions initially in the cavernous sinus and later in the convexity pachymeninges. The lesions disappeared following 9 months of oral prednisolone (15 mg/day) and cyclophosphamide (100 mg/day) therapy. The presence of c-ANCA, demonstration of vasculitis, and depositions of immunoglobulin G (IgG) and fibrinogen in the vessel walls of pachymeninges of the patient confirmed an immune-mediated cause of the vasculitis. Cranial pathology without renal and pulmonary involvement suggests a variant of Wegener's granulomatosis, which is called the "limited" form of Wegener's granulomatosis. MRI, Raeder's paratrigeminal neuralgia, localized pachymeningitis.

Aged↗
PubMed1993

Mitomycin-induced synthesis of a Shiga-like toxin from enteropathogenic Escherichia coli H.I.8.

Escherichia coli H.I.8, an O128 infant diarrhea isolate, produces low titers of a unique Shiga-like toxin (SLT), called SLT-IIva, which is a variant of SLT-II. We investigated induction of toxin synthesis and the putative association of a bacteriophage with toxin synthesis. Induction of broth cultures of strain H.I.8 with mitomycin yielded a 3,000-fold increase in SLT-IIva, production of a colicin, and appearance of a bacteriophage. Southern hybridization demonstrated that the genes for SLT-IIva were not carried by the bacteriophage.

Bacterial Toxins↗
PubMed1995

Quantitative differences in adhesiveness of type 1 fimbriated Escherichia coli due to structural differences in fimH genes.

Type 1 fimbriae are heteropolymeric surface organelles responsible for the D-mannose-sensitive (MS) adhesion of Escherichia coli. We recently reported that variation of receptor specificity of type 1 fimbriae can result solely from minor alterations in the structure of the gene for the FimH adhesin subunit. To further study the relationship between allelic variation of the fimH gene and adhesive properties of type 1 fimbriae, the fimH genes from five additional strains were cloned and used to complement the FimH deletion in E. coli KB18. When the parental and recombinant strains were tested for adhesion to immobilized mannan, a wide quantitative range in the ability of bacteria to adhere was noted. The differences in adhesion do not appear to be due to differences in the levels of fimbriation or relative levels of incorporation of FimH, because these parameters were similar in low-adhesion and high-adhesion strains. The nucleotide sequence for each of the fimH genes was determined. Analysis of deduced FimH sequences allowed identification of two sequence homology groups, based on the presence of Asn-70 and Ser-78 or Ser-70 and Asn-78 residues. The consensus sequences for each group conferred very low adhesion activity, and this low-adhesion phenotype predominated among a group of 43 fecal isolates. Strains isolated from a different host niche, the urinary tract, expressed type 1 fimbriae that conferred an increased level of adhesion. The results presented here strongly suggest that the quantitative variations in MS adhesion are due primarily to structural differences in the FimH adhesin. The observed differences in MS adhesion among populations of E. coli isolated from different host niches call attention to the possibility that phenotypic variants of FimH may play a functional role in populations dynamics.

Adhesins, Bacterial↗
PubMed1980

G6PD (Dublin): chronic non-spherocytic haemolytic anaemia resulting from glucose-6-phosphate dehydrogenase deficiency in an Irish kindred.

A new variant of G6PD associated with chronic non-spherocytic haemolytic anaemia (CNSHA) in an Irish male is described. This variant is unique in that it has a normal electrophoretic mobility, Michaelis constant for G6P and NADP, and a normal pH optimum, together with a marked increase in utilisation of the substrate 2 deoxy glucose-6-phosphate. It is also relatively heat stable when compared with the normal (B) variant. These characteristics distinguish this variant from previously reported variants associated with CNSHA and we have called it G6PD Dublin.

Adult↗
PubMed1982

G6Pd Kanazawa: a new variant of glucose-6-phosphate dehydrogenase associated with congenital nonspherocytic hemolytic anemia.

A new variant of G6PD associated with chronic nonspherocytic hemolytic anemia (CNSHA) in a Japanese male is described. This variant is unique in that it has a normal electrophoretic mobility, normal Km for glucose-6-phosphate and NADP, and a normal utilization of the substrate 2-deoxyglucose-6-phosphate and deamino-NADP. It also shows a decreased thermal stability and a biphasic pH curve. These characteristics distinguish this variant from previously reported variants associated with CNSHA and we have called it G6PD Kanazawa.

Adult↗
PubMed2006

Spontaneous opticospinal encephalomyelitis in a double-transgenic mouse model of autoimmune T cell/B cell cooperation.

We describe a double-transgenic mouse strain (opticospinal EAE [OSE] mouse) that spontaneously develops an EAE-like neurological syndrome closely resembling a human variant of multiple sclerosis, Devic disease (also called neuromyelitis optica). Like in Devic disease, the inflammatory, demyelinating lesions were located in the optic nerve and spinal cord, sparing brain and cerebellum, and the murine lesions showed histological similarity with their human correlates. OSE mice have recombination-competent immune cells expressing a TCR-alphabeta specific for myelin oligodendrocyte glycoprotein (MOG) aa 35-55 peptide in the context of I-Ab along with an Ig J region replaced by the recombined heavy chain of a monoclonal antibody binding to a conformational epitope on MOG. OSE mouse B cells bound even high dilutions of recombinant MOG, but not MOG peptide, and processed and presented it to autologous T cells. In addition, in OSE mice, but not in single-transgenic parental mice, anti-MOG antibodies were switched from IgM to IgG1.

Animals↗
PubMed1985

Topographic electroencephalographic study with power ratio index mapping in patients with malignant brain tumors.

A variant of electroencephalogram (EEG) power spectral mapping called power ratio index (PRI) mapping was used to monitor 15 patients with malignant brain tumors. This index is generated by dividing the low frequency (delta, theta) power by the high frequency (alpha, beta) power. Because the nonparoxysmal effect of a brain tumor on the EEG is reflected as a relative loss of high frequency power and a gain in low frequency power, utilization of the PRI has the effect of placing the epicenter of the "power dysfunction" coincident with the epicenter of the tumor.

Adult↗
PubMed2005

Competitive regulation of modular allosteric aptazymes by a small molecule and oligonucleotide effector.

The hairpin ribozyme can catalyze the cleavage of RNA substrates by employing its conformational flexibility. To form a catalytic complex, the two domains A and B of the hairpin-ribozyme complex must interact with one another in a folding step called docking. We have constructed hairpin ribozyme variants harboring an aptamer sequence that can be allosterically induced by flavin mononucleotide (FMN). Domains A and B are separated by distinct bridge sequences that communicate the formation of the FMN-aptamer complex to domains A and B, facilitating their docking. In the presence of a short oligonucleotide that is complementary to the aptamer, catalytic activity of the ribozyme is completely abolished, due to the formation of an extended conformer that cannot perform catalysis. However, in the presence of the small molecule effector FMN, the inhibitory effect of the oligonucleotide is competitively neutralized and the ribozyme is activated 150-fold. We thus have established a new principle for the regulation of ribozyme catalysis in which two regulatory factors (an oligonucleotide and a small molecule) that switch the ribozyme's activity in opposite directions compete for the same binding site in the aptamer domain.

Allosteric Regulation↗
PubMed2002

Follicular, papillary, and "hybrid" carcinomas of the thyroid.

The existence of well-differentiated thyroid tumors sharing the clinicopathologic features of follicular and papillary carcinoma is discussed using the so-called diffuse (multinodular) form of the follicular variant of papillary carcinoma as a paradigm. Although the concept of a hybrid carcinoma of the thyroid is intellectually very appealing, we conclude that there is not (yet) enough reliable genotypic or phenotypic evidence to support utilization of such a term.

Adenocarcinoma, Follicular↗
PubMed2004

[Matrix-producing breast carcinoma with myoepithelial differentiation--description of 11 cases and review of literature aimed at histogenesis and differential diagnosis].

OBJECTIVE: Presentation of variable morphology of the so-called matrix-producing carcinoma, the rare variant of metaplastic breast carcinoma. Establish the extent of myoepithelial phenotype by immunohistochemistry and assess behaviour of the lesion. DESIGN: Review of clinicopathologic data of 11 cases. SETTING: Private Biopsy Lab s.r.o., Pilsen and Sikl's Department of Pathology, Charles University and Faculty Hospital, Pilsen. METHODS: Included are eleven cases from Breast Registry, Biopsy Lab s.r.o., Pilsen and Pathology Department, Faculty Hospital in Hradec Králové and Martin and from Biopsy Lab in Horovice. Analyzed were morphology, stage, grade and follow up. Myoepithelial phenotype was demonstrated immunohistochemically by LSAB+ system (DAKO) and seven conventional myoepithelial markers (GFAP, aktin S, calponin, cytokeratin 14, p63, CD10 and P-cadherin) were used. Oncogene p53 and Her2/neu were also detected. RESULTS: Matrix-producing carcinoma is an extremely rare type of metaplastic carcinoma of the breast, where high-grade epithelial component continually merges with heterologous mesenchymal chondroid component without overt spindle cell sarcomatoid pattern in between. There were all women at the age of 32 to 86-years (average 54 years, median 52 years) and the maximum tumor diameter ranged from 18 to 60 mm (average 32 mm). The axillary LN was positive in six cases in the time of diagnosis. The follow up available in 9 women ranged from three months to ten years (average 24 months); dissemination of the disease was observed in three cases; 2 of these patients died of disease after three and ten years, respectively. The heterologous mesenchymal chondroid component was produced in two different ways; one displayed typical structure of low-grade hyaline cartilage, in the second one the epithelial tumorous cells were embedded in the homogenous eosinophilic extracellular matrix giving appearance of chondroid aura. Metaplastic component constituted 5-75% of the tumor volume. Immunohistochemical evidence of myoepithelial differentiation in all neoplasms was demonstrated, with at least two conventional myoepithelial markers (actin S, calponin, GFAP, CK14, CD10, p63 and P-cadherin) being positive in every case. Expression of p53 was identified in six cases, all tumors were Her2/neu negative. Histologically the metastases were formed either by carcinoma cells only, or more frequently, they replicated the structure of primary lesion. CONCLUSION: As a rare entity, matrix-producing carcinoma of breast displaying myoepithelial phenotype, deserves separate position in tumor classification. It differs from conventional myoepithelial carcinoma and from heterologous metaplastic carcinoma, where the matrix emanate from undifferentiated sarcomatous tissue, but precise histogenesis in not clear yet. This is a very aggressive lesion and our findings show that previous reports of indolent behaviour were preliminary. Spectrum of differential diagnosis, namely benign mixed tumor, phylloid tumor, primary breast sarcoma and colloid carcinoma warrant clear knowledge about this unique entity.

Adult↗
PubMed2006

[Serrated, hyperplastic and hyperplasia-like colorectal polyps].

The colorectal hyperplastic polyp has generally been considered a finding of no clinical significance. Recent research has, however, called attention to the existence of some variants of hyperplastic polyp which are potentially malignant. The term "advanced serrated polyp" has been coined for such cases, which comprise mixed hyperplastic/adenomatous tissue, serrated adenoma, and sessile serrated polyp, in contrast to the traditional hyperplastic polyp. Since epithelial dysplasia is an integrated component of mixed hyperplastic/adenomatous polyp and of the serrated adenoma, such a diagnosis would dictate control colonoscopy comparable to the guidelines for subjects with conventional adenomas. The cytology of the sessile serrated polyp is, however, closer to that of the traditional hyperplastic polyp, whereas the architecture mimics that of the serrated adenoma. For this reason, a consensus regarding the optimal management of such patients has not been obtained, but if the polyp is sizeable and located in the right colon, control should be considered. The small, usually left-sided traditional polyp as a rule needs no follow-up, but the context in which such a lesion is found and its morphology may influence the clinical decision. Future large-scale investigations of serrated colorectal polyps, including interobserver studies, will be required to identify histological details of clinical utility which can be adopted in daily routine practice.

Adenoma↗
PubMed1977

[So-called pseudolymphomatosis of the stomach].

An observation of a polymorphnocellular variant of pseudolymphomatosis of the stomach diagnosed retrospectively is described. Initially, the case was treated as lymphogranulomatosis of the stomach, and in connection with the latter the patient was given long-term immunodepressive therapy. At autopsy (6 years later) atrophy of the lymphoreticular tissue and mucinous carcinoma of the stomach were revealed. The authors hold that the second tumour developed against the background of the immuno-depressive therapy, whereas at the beginning the condition was pseudolymphomatosis.

Adenocarcinoma, Mucinous↗
PubMed1977

Characteristics of a new abnormal variant of G-6-PD in human red cells.

Kinetic and electrophoretic properties were studied in 230--300 fold purified preparations of glucose-6-phosphate dehydrogenase (G-6-PD) from red cells of donors and patients with hemolytic anemia induced by G-6-PD deficiency. In abnormal variant of G-6-PD isolated from red cells of a patient with hemolytic anemia which had not before been described in the literature was found. The abnormal variant differs from the normal enzyme by a decreased Michaelis constant for G-6-P and NADP, by increased utilization of substrate-analogues (2-deoxy-G-6-P and deamino NADP in particular), by low heat stability, the character of pH dependence, and by the appearance of one band of G-6-PD activity during electrophoresis in polyacrylamide gel. The isolated abnormal variant of G-6-PD has been called "Kremenchug" according to the origin of the patient.

Electrophoresis, Polyacrylamide Gel↗
PubMed1988

[Piso-triquetral arthrosis and the so-called pisiform secundarium].

After scapho-trapezial osteoarthritis, piso-triquetral is the next most common. Some of the various changes of the piso-triquetral osteoarthritis are also to be seen in the dorso-volar view. The so-called secondary pisiform is not a congenital variant but develops with increasing frequency in older age as one of the features of the osteoarthritic reactions.

Adult↗
PubMed1998

[Diagnosis of Duchenne and Becker muscular dystrophy in Slovak patients using multiplex polymerase chain reaction].

The authors of the paper describe the diagnostic method of deletion in the dystrophin gene by means of an improved variant of the polymerase chain reaction--so called multiplex PCR. The authors analyzed a group of 66 patients with developed clinical symptoms of the disease. The deletion screening included 22 exones of the dystrophine gene and it was performed in 5 multiplex PCR reactions. 20 patients yielded a verified deletion which was pre-assessed by Southern's hybridization. The relative simplicity of multiplex PCR which does not require the use of radioisotopes, its low time and financial needs, make this method to represents an appropriate alternative of Southern's hybridization in the assessment of deletion of the dystrophine gene. (Fig. 1, Ref. 19.)

Dystrophin↗
PubMed1986

Presence of a plasma transthyretin (prealbumin) variant in familial amyloidotic polyneuropathy in a kindred of Greek origin.

Human plasma transthyretin (TTR, a protein formerly called prealbumin) is known to be associated with familial amyloidotic polyneuropathy (FAP) of autosomal inheritance. A variant TTR with a methionine-for-valine substitution at position 30 has been described as the major protein component of amyloid in Portuguese and Japanese patients with FAP and in patients of Swedish ancestry with FAP. In these patients, TTR(Met30) also circulates in relatively low concentration in the plasma. TTR variants having substitutions in other positions have also been reported in a patient of Jewish origin with FAP. We now report studies on TTR from an FAP kindred of Greek ancestry. By peptide mapping analysis, plasma TTR from the propositus was compared with TTR from a Portuguese patient with FAP. TTR(Met30) was found to circulate in the blood plasma of the Greek propositus. By use of a recently developed immunoblotting technique, this variant TTR was also detected in some of the relatives of the propositus. Future studies of this mutant gene among ethnically different FAP populations might contribute to an understanding of selection and persistence of the mutation.

Amino Acid Sequence↗
PubMed1978

Defective and enhanced postreplication repair in classical and variant xeroderma pigmentosum cells treated with N-acetoxy-2-acetylaminofluorene.

Xeroderma pigmentosum (XP) cells proficient in the excision repair of pyrimidine dimers (XP variants) were also found to be proficient in the excision repair of N-2-acetoxyacetylaminofluorene (AAAF)-induced lesions in their DNA, as assayed by the photolysis of 5-bromodeoxyuridine incorporated during repair. However, the time in which the small segments of newly synthesized DNA, made immediately after treatment of cells with AAAF, were joined together to form DNA of parental size by a process called postreplication repair was long in the XP variant and classical cells. Although increasing doses of AAAF increased the time for making daughter DNA of parental size for variant and classical XP cells, AAAF did not appear to affect this process in normal human cells. Treatment of variant and classical XP cells with a relatively small dose (2.5 micron) of AAAF or 2.5 J/sq m of UV radiation several hr before a 2- to 3-fold-larger dose decreased the time for the pulse-labeled DNA to appear as parental size.

Acetoxyacetylaminofluorene↗
PubMedDate not supplied

Actinic prurigo, tropical (South-East Asian) variant.

Actinic prurigo is a chronic familial photodermatitis found predominantly among the Amerindians. It has been reported from North and South America, Britain and Japan. We report a case of actinic prurigo seen in Singapore. A 20-year-old Malay female presented with a persistent pruriginous eruption in the sun-exposed parts and on her abdomen. She also had lower lip cheilitis and thinning of the outer eyebrows, features often seen in actinic prurigo. The minimal erythema dose to ultraviolet A (UVA) and UVB were persistently lowered. We propose that this condition be called actinic prurigo, tropical (South-East Asian) variant.

Adult↗