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PubMed1991

Cheiro-oral syndrome: identification of the lesion sites and a proposal for its clinical classification.

Five cases suffering from unilateral paresthesia over the corner of the mouth and the hand on the same side were examination for cheiro-oral syndrome. Of these, three cases were typical and the other were variant cases associate with transient hemi-signs. Lesion sites were identified by computed tomographic (CT) scan, magnetic resonance imaging (MRI) or both. Of the five patients, lesions were due to thalamic infarction in three cases, pontine hemorrhage in one case, and tumor compression on the right frontoparietal lobe in the last case. The pathophysiology of all cases were classified according to location of the lesion on the thalamus, the pons, and the parietal lobe, which are the usual anatomical sites responsible for this syndrome. Based on the three typical cases and thirteen cases cited from the English literature, a clinical classification has been established. The classification is based on age at the time of onset, gender, lesion site, etiology, risk factors, and certain clinical features. These sixteen cases fell into three distinct groups: a) those in which the thalamic lesions were related to infarction, b) those in which tumors, or in rare cases infarction, were found in the parietal lobe, and c) those in which hemorrhage occurred in the pons. Using this classification, the cheiro-oral syndrome can be more systematically defined.

Female↗
PubMed1995

Palmoplantar keratoderma and associated syndromes.

This article focuses on the current state of knowledge concerning the characterization and classification of palmoplantar keratoderma and associated syndromes. In addition, therapeutic options are discussed. Exact diagnosis enables dermatologists to give patients accurate genetic counseling and may help to detect underlying defects or proneness to cancer. Furthermore, precise classification of this disease facilitates the use of the most efficient therapeutic modalities. Important criteria for the classification of palmoplantar keratoderma are the mode of transmission, age at onset, and distribution of the keratoderma. The disorder may be diffuse or focal; it may be restricted to the palms and soles or also involve the dorsal aspects of the hands and feet. Psoriatic-like lesions in other parts of the body may occur in certain variants. The association of other signs and symptoms may provide diagnostic clues. Ultrastructural investigation will show diagnostic features in some types of palmoplantar keratoderma, and biochemical analysis may be helpful in the classification of keratoderma. In the future, the most accurate diagnosis will be the identification of the genetic defect and its chromosomal localization.

Diagnosis, Differential↗
PubMed1998

Guillain-Barré syndrome variants in Emilia-Romagna, Italy, 1992-3: incidence, clinical features, and prognosis. Emilia-Romagna Study Group on Clinical and Epidemiological Problems in Neurology.

OBJECTIVES: To estimate the incidence rate of Guillain-Barré syndrome variants in an unselected population and to describe their clinical features and prognosis. METHODS: A two year prospective multicentre study on the incidence and prognosis of Guillain-Barré syndrome was performed in Emilia-Romagna, northern Italy (3,909,512 inhabitants). A surveillance system was instituted within the study area, which comprised all the neurological departments, private and public general hospitals, and practising neurologists. The international classification of diseases (ICD) codes 357.XX (any peripheral neuropathy) of hospital discharges were also reviewed. RESULTS: Data were separately analysed for Miller Fisher syndrome and other Guillain-Barré syndrome variants. During the study period 18 patients with Guillain-Barré syndrome variants including seven with Miller Fisher syndrome were recruited; the incidence rates were 0.14/100000/year (95% confidence interval (95% CI) 0.07-0.25) for Guillain-Barré syndrome variants (excluding Miller Fisher syndrome) and 0.09/100000/year (95% CI 0.04-0.18) for Miller Fisher syndrome. Guillain-Barré syndrome variants alone (excluding Miller Fisher syndrome) accounted for 10.5% of total cases. Death and relapses were not found. Details of clinical, electrophysiological, and CSF findings of Guillain-Barré syndrome variants are provided. CONCLUSIONS: Guillain-Barré syndrome variants other than Miller Fisher syndrome, as obtained through a population based study, account for about 10% of total cases of Guillain-Barré syndrome and, as a whole, have a good prognosis. Their clinical features are heterogeneous; bifacial weakness (associated with other signs, mainly sensory disturbances) represents the most frequent finding.

Adolescent↗
PubMed1989

Chronic neutrophilic leukemia with dysplastic features. A new variant of the myelodysplastic syndromes.

We are reporting four patients who presented with a persistent increase of mature neutrophils and band forms, no monocytosis in repeated examinations and with dysplastic features in blood and bone marrow. Two of them developed acute myeloid leukemia (AML; FAB classification M1) and the other two were characterised by a progressively aggravating myelodysplasia. All the patients showed a poor response to treatment and died within a period of time ranging from 14 to 80 months after diagnosis. We are proposing the term chronic neutrophilic leukemia with dysplastic features (CNL-D) for this entity, and we believe that it represents a variant of the myelodysplastic syndromes.

Aged↗
PubMed2002

Differential expression profiling of head and neck squamous carcinoma: significance in their phenotypic and biological classification.

The genetic events associated with the development and progression of head and neck squamous carcinoma (HNSC) are largely unknown. We analysed 12 matched pairs of histologically normal squamous mucosa and tumor specimens from six conventional and six phenotypic variants HNSC to define the differentially expressed genes in these tumors. Parallel expression analysis of 8055 unique genes was performed, and the level of the hybridization signal for each gene was measured after normalization. Hierarchical cluster analysis of the expressed genes showed distinct inter- and intra-tumoral patterns in and between conventional squamous carcinoma and squamous carcinoma variants. We also identified 26 (0.32%) differentially expressed genes that were consistently different between matched pairs of normal and tumor specimens; a selected set of the overexpressed genes was validated using real-time quantitative RT-PCR. The majority of the genes were associated with differentiation and proliferation. Our study defines a set of genes that could form the basis for the construction of limited HNSC targeted expression array and in-depth studies and further highlights gene profile differences that may be useful in pathobiologic classification of HNSC.

Adult↗
PubMed2000

Liposarcoma: new entities and evolving concepts.

Liposarcoma is the most common soft tissue sarcoma and accounts for approximately 20% of all mesenchymal malignancies. In the last decade, the results of several studies have led to the delineation of new variants as well as to the introduction of new concepts, mainly as a result of the fruitful interactions between genetics and pathology. Spindle cell liposarcoma represents an uncommon variant of well-differentiated liposarcoma. It tends to occur in adults and often involves the subcutaneous soft tissue. However, from the observation of a larger number of cases, the anatomic distribution of spindle cell liposarcoma seems to be comparable to that of the other well-differentiated liposarcoma subtypes. Spindle cell liposarcoma tends to recur locally and may dedifferentiate. Morphologically it is composed of a fairly bland neural-like spindle cell proliferation set in a fibrous and/or myxoid background and is associated with an atypical lipomatous component. Great debate has been generated by the introduction of the term atypical lipoma to emphasize the fact that well-differentiated liposarcoma shows risk of local recurrence but no potential for metastasis. In our opinion well-differentiated liposarcoma and atypical lipoma should be considered synonyms that describe lesions identical both morphologically and kayotypically. Dedifferentiated liposarcoma is a distinct type of liposarcoma in which transition from low-grade to high-grade nonlipogenic morphology within a well-differentiated liposarcoma is observed. The transition usually occurs in an abrupt fashion; however, in rare cases it can be more gradual. Recently, it also has been proposed that dedifferentiated liposarcoma should be further classified into low and high grade. Dedifferentiated liposarcoma rarely exhibits heterologous (most often myoid) differentiation. A peculiar "neural-like whorling pattern" of dedifferentiation also has been described recently. Surprisingly, the clinical outcome of dedifferentiated liposarcoma is less aggressive that in other high-grade pleomorphic sarcomas but genetic as well as molecular data exist that may partiallyjustify such a discrepancy. Myxoid and round cell liposarcoma, even if still classified by the World Health Organization as two distinct subtypes, share both clinical and morphologic features. Lesions combining both patterns are very frequent and wide agreement exists in considering round cell liposarcoma as the high-grade counterpart of myxoid liposarcoma. Furthermore, myxoid and round cell liposarcoma share the same characteristic chromosome change. Albeit rare, it has been recently shown that liposarcoma indeed can occur as a primary skin lesion. It often presents clinically as a dome-shaped or polypoid lesion that, histologically, most frequently shows high-grade morphologic features but carries a comparatively good prognosis. Considering currently available data, the most logical classification of liposarcoma is into three main groups: (1) well-differentiated liposarcoma (including adipocytic, sclerosing, inflammatory, spindle-cell, and dedifferentiated variants), characterized by ring or long markers chromosomes derived from the long arm of chromosome 12; (2) myxoid and round cell (poorly differentiated myxoid) liposarcoma, characterized in most cases by a reciprocal translocation t(12;16)(q13;p11); and (3) pleomorphic liposarcoma, characterized by complex karyotypes.

Adult↗
PubMed2004

Using morphometry of the larval rostellar hooks to distinguish Iranian strains of Echinococcus granulosus.

Human cystic echinococcosis is widely distributed throughout Iran, where sheep, cattle, goats, camels and other animals act as intermediate hosts. It appears that morphometry of the rostellar hooks on the protoscoleces of the causative parasite, Echinococcus granulosus, can be used to separate the strains or variants of the parasite to be found in humans and livestock in Iran. Multivariate statistical procedures, including principal-component analysis and discriminant-function analysis (DFA), were used to explore the morphometric data obtained from the larval hooks of Iranian samples of E. granulosus. Although five physical variables were initially considered, the results of the PCA indicated that just two factors (based on the length of hooks and number of hooks) accounted for 91.6% of the variance observed in the hook measurements. The results of the DFA allowed the correct classification of all the samples. The presence in Iran of the sheep and camel strains of the parasite was confirmed. The sheep strain was the most common variant encountered, being recovered from sheep, cattle, goats, humans and occasionally camels. Most of the metacestode samples from camels and a few of those from cattle (five of 30), sheep (one of 27) and humans (two of 23) were found to be of the camel strain. These results indicate that larval-hook morphology is a valid method for identifying E. granulosus strains in Iran, and one that is potentially useful for epidemiological studies.

Animals↗
PubMed2004

Expression and localization of fibroblast growth factor (FGF) family members during the final growth of bovine ovarian follicles.

The aim of this study was to investigate the possible participation of fibroblast growth factor (FGF) family members: FGF1, FGF2, and FGF7, and their receptor variants: FGFR, FGFR2IIIb, and FGFR2IIIc in theca interna (TI) and granulosa cell (GC) compartments of bovine follicles during final growth. A classification of follicles into five groups (<0.5; >0.5-5; >5-20; >20-180; >180 ng/ml, respectively) was performed according to the follicular fluid (FF) oestradiol-17beta (E) content. The mRNA expression and protein localization was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. FGF1 mRNA expression was relatively high in TI and lower in GC, and without any regulatory change for both tissue compartments during final follicular growth. The FGF1 protein could be predominantly localized in the cytoplasm of GC, in smooth muscle cells of blood vessels, in the rete ovarii, and at a lesser degree in theca cells. FGF2 mRNA in TI increased significantly in large follicles and was low and without any regulatory change in GC. FGF7 mRNA expression was relatively high in TI and very low in GC. For FGF7 in mature follicles a marked staining of the TI and the basal layers of the GC could be demonstrated. The mRNA signal for the FGFR in TI increased significantly with beginning of E production (E > 0.5-5 ng/ml FF) and was without any regulatory change in GC. The mRNA expression of FGFR2IIIb was relatively high in GC and increased significantly during final growth of follicles in contrast to the TI with very low expression. The FGFR2IIIc mRNA expression in TI and GC was relatively high but without any clear change. Our results suggest that FGF growth factor family members are involved in process of folliculogenesis and especially during final growth of the preovulatory (dominant) follicle by stimulation of angiogenesis and GC survival and proliferation.

Animals↗
PubMed2004

Collecting duct carcinoma: an entity to be redefined?

Collecting duct carcinomas (CDCs) are highly aggressive tumors with poor survival at 1 year and are often metastatic at the time of diagnosis. It has been shown that patients may have better survival when treated with a chemotherapy regimen used for urothelial carcinoma. Such tumors must therefore be recognized, but their pathological diagnosis remains difficult. The two main differential diagnoses are renal pelvis urothelial carcinoma with infiltration of the kidney and/or high-grade and high-stage papillary renal cell carcinoma. The aim of our study was to compare the immunophenotype of 14 CDCs with 6 renal pelvis urothelial carcinomas (RPUC) infiltrating the medulla. The following markers were evaluated: ulex europeus aglutinin (UEA), peanuts aglutinin, vimentin and aquaporin 3 (AQP-3), a membrane component of normal collecting duct and urothelial cells. We were able to define a reproductive urothelial phenotype AQP-3+, vimentin- and UEA+. Among the 14 CDCs, 10 cases demonstrated this immunophenotype. It coincided with an urothelial-like trabecular and tubular pattern. In contrast, the 4 remaining papillary CDCs had the inverse pattern, AQP-3-, vimentin+ and UEA-. These results suggest that: (1) the trabecular and tubular variant of CDC with the urothelial AQP-3+, vimentin- phenotype can be included in the spectrum of urothelial diseases; (2) the papillary variant probably does not belong to the same entity; (3) AQP-3 is a marker of interest for improving the histological classification of CDC and unclassified aggressive renal tumors.

Aged↗
PubMed2005

Comparison of relevance learning vector quantization with other metric adaptive classification methods.

The paper deals with the concept of relevance learning in learning vector quantization and classification. Recent machine learning approaches with the ability of metric adaptation but based on different concepts are considered in comparison to variants of relevance learning vector quantization. We compare these methods with respect to their theoretical motivation and we demonstrate the differences of their behavior for several real world data sets.

Artificial Intelligence↗
PubMed1999

7TM receptors: the splicing on the cake.

Within a given family of seven transmembrane domain (7TM) receptors, functional diversity is most often afforded by the existence of multiple receptor subtypes, each encoded by a distinct gene. However, it is now clear that the existence of introns in genes encoding some members of a receptor family provides scope for additional diversity by virtue of splicing events that result in the formation of different receptor mRNAs and consequently distinct receptor isoforms. A large number of 7TM receptor splice variants have now been shown to exist. In this article, the current data on alternatively spliced variants for hormone and neurotransmitter 7TMs are reviewed, their potential physiological importance considered and some of the issues pertaining to the classification and nomenclature of receptor isoforms produced in this way are addressed.

Genetic Variation↗
PubMed1994

Morphology and cytochemistry of acute lymphoblastic leukaemia.

ALL is characterized by small to medium sized leukaemic blasts with a rather low grade of cell-to-cell variability. The nucleocytoplasmic ratio is high with just a small cytoplasmic rim in many cases. The cytoplasm tends to be moderately basophilic. Usually, though not in each instance, it is agranular and free of vacuoles. The chromatin is more condensed than in AML and the nucleoli tend to be indistinct. The FAB classification of haematological malignancies separates ALL into three categories: ALL L1, L2, and L3. However, just the identification of the L3 variant is of major importance. The L3 cells are medium sized to large and are characterized by intensely basophilic and moderately abundant cytoplasm with prominent cytoplasmic vacuolation in the bone marrow but not necessarily in the peripheral blood. According to our experience there is a high but not universal correlation of the L3 phenotype as defined by morphology with the immunologically defined B-ALL with surface expression of immunoglobulins. Until recently, acute leukaemias proving negative for all cytochemical tests especially for the PAS reaction and for the focal type of acid phosphatase, were termed 'acute undifferentiated leukaemia' (AUL). However, this morphological/cytochemical diagnosis may be confused with the immunological diagnosis of unclassifiable leukaemia. Since almost any of these cases can be recognized as ALL or AML by immunology, the term AUL should be reserved for cases which can be classified neither by morphology/cytochemistry nor by immunology. The morphological and cytochemical distinction of ALL from poorly differentiated AML remains a problem, especially if the FAB criteria for distinguishing ALL from AML by cytochemistry (3% of the blasts positive for peroxidase) are applied rigidly. A small but significant percentage of poorly differentiated leukaemias have less than 3% of the blasts positive for peroxidase and the myeloid nature of the leukaemia can be identified by cytochemistry. The absence of blasts being positive for peroxidase is no reliable indicator for the lymphatic nature of a leukaemia, even if the PAS reaction is typical for ALL. The morphological diagnosis of ALL needs confirmation by immunology in each instance.

Adult↗
PubMed2006

Absence of association between the multidrug resistance (MDR1) gene and inflammatory bowel disease.

OBJECTIVE: The multidrug resistance (MDR1) gene encodes for P-glycoprotein, a drug efflux pump. Mice deficient for the MDR1a gene spontaneously develop colitis. In humans, a polymorphism in exon 26 (C3435T) is associated with reduced expression levels and function of MDR1. Currently there are controversial data on the association between MDR1 and inflammatory bowel disease (IBD). The purpose of this study was to examine the involvement of this gene in IBD in a large population of Dutch patients with IBD and family-based controls. MATERIAL AND METHODS: A total of 781 IBD cases and 315 controls were investigated. CD phenotypes were determined according to the Vienna Classification. Individuals were genotyped for six single nucleotide polymorphisms (SNPs) close to and in the MDR1 locus. This included the C3435T variant and six microsatellite markers close to and in the MDR1 locus. Single locus association analysis, haplotype association analysis and haplotype sharing statistic (HSS) were used to search for differences between patients and controls. RESULTS: No association was observed for any of the SNPs with IBD as a group, or for ulcerative colitis, Crohn's disease and Crohn's disease phenotypes, either by single locus or haplotype association analysis or by HSS. CONCLUSIONS: No association was observed between the MDR1 gene and IBD. This suggests that it is unlikely that MDR1 plays a role in IBD susceptibility.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Molecular diagnostics of epidermolysis bullosa: novel pathomechanisms and surprising genetics.

Tremendous progress has been recently made in understanding the molecular basis of epidermolysis bullosa (EB), and as of today specific mutations have been delineated in 10 distinct genes in different subtypes of this genodermatosis. Molecular diagnostics of EB has implications for improved classification with prognostic significance, refined genetic counseling, and establishment of DNA-based prenatal testing. During elucidation of mutations in different variants of EB, novel pathomechanisms, including uniparental isodisomy in junctional EB and de novo dominant mutations in dystrophic EB, have been encountered. These observations have relevance to counseling the families of the risk of recurrence of EB in subsequent pregnancies in the same and future generations.

Collagen↗
PubMed1997

Antigenic and molecular analyses of different Chlamydia pneumoniae strains.

Chlamydia pneumoniae is an important human respiratory pathogen. Classification of C. pneumoniae isolates into distinguishable serovars or genotypes has not yet been reported. To determine whether antigenic or molecular variants among C. pneumoniae isolates exist, six strains were studied via immunoblot analysis and DNA sequence determination of the entire major outer membrane protein (MOMP) gene omp1. The strains included four prototype strains and two clinical isolates from our laboratory. Immunoblot analysis of sera from patients infected with C. pneumoniae revealed antigenic differences between the C. pneumoniae strains. Strong reactivity of one serum sample with a 65-kDa protein in two C. pneumoniae strains which was not observed with the other strains was the most prominent finding. All sera reacted with the 40-kDa MOMP. Comparison of the omp1 DNA sequences revealed that the omp1 genes of all strains were identical and were 100% identical to the sequence of the omp1 gene of C. pneumoniae AR-39. The results of this study demonstrate that unlike C. trachomatis, the omp1 gene is conserved in C. pneumoniae. Furthermore, it was shown that C. pneumoniae strains are antigenically different. This finding indicates that more than one serovar of C. pneumoniae exist.

Antigenic Variation↗
PubMed2004

Bioinformatics analysis of SARS coronavirus genome polymorphism.

BACKGROUND: We have compared 38 isolates of the SARS-CoV complete genome. The main goal was twofold: first, to analyze and compare nucleotide sequences and to identify positions of single nucleotide polymorphism (SNP), insertions and deletions, and second, to group them according to sequence similarity, eventually pointing to phylogeny of SARS-CoV isolates. The comparison is based on genome polymorphism such as insertions or deletions and the number and positions of SNPs. RESULTS: The nucleotide structure of all 38 isolates is presented. Based on insertions and deletions and dissimilarity due to SNPs, the dataset of all the isolates has been qualitatively classified into three groups each having their own subgroups. These are the A-group with "regular" isolates (no insertions / deletions except for 5' and 3' ends), the B-group of isolates with "long insertions", and the C-group of isolates with "many individual" insertions and deletions. The isolate with the smallest average number of SNPs, compared to other isolates, has been identified (TWH). The density distribution of SNPs, insertions and deletions for each group or subgroup, as well as cumulatively for all the isolates is also presented, along with the gene map for TWH. Since individual SNPs may have occurred at random, positions corresponding to multiple SNPs (occurring in two or more isolates) are identified and presented. This result revises some previous results of a similar type. Amino acid changes caused by multiple SNPs are also identified (for the annotated sequences, as well as presupposed amino acid changes for non-annotated ones). Exact SNP positions for the isolates in each group or subgroup are presented. Finally, a phylogenetic tree for the SARS-CoV isolates has been produced using the CLUSTALW program, showing high compatibility with former qualitative classification. CONCLUSIONS: The comparative study of SARS-CoV isolates provides essential information for genome polymorphism, indication of strain differences and variants evolution. It may help with the development of effective treatment.

Amino Acid Sequence↗
PubMed2007

Surgically relevant normal and variant renal parenchymal and vascular anatomy in preoperative 16-MDCT evaluation of potential laparoscopic renal donors.

OBJECTIVE: Using 16-MDCT, we describe and quantify the frequency and types of renal anatomic variants and findings relevant for preoperative evaluation and surgical planning for potential laparoscopic renal donors. MATERIALS AND METHODS: On 16-MDCT, 126 consecutive potential donors underwent scanning before contrast administration and after i.v. power injection of nonionic contrast material during the arterial, nephrographic, and excretory phases. On a 3D workstation, CT images were evaluated retrospectively in consensus by three abdominal imagers. The number and branching pattern of bilateral renal arteries and veins, including anomalies of the inferior vena cava and lumbar-gonadal axis, were categorized along with the frequency of incidental findings of the renal parenchyma and collecting system. RESULTS: Major arterial variants including supernumerary and early branching arteries were present in 16% and 21%, respectively, of left kidneys and 22% and 15%, respectively, of right kidneys. Major and minor venous variants were detected in 11% and 58% of left kidneys and 24% and 3% of right kidneys. Late confluence of the venous trunk was identified in 17% of left kidneys and 10% of right kidneys. Incidental parenchymal and urothelial abnormalities, most commonly cysts and calyceal calcifications, were identified in 30% of the kidneys. Other relevant incidental findings included focal infarcts, cortical scars, atrophic scarred kidney, and bilateral papillary necrosis. Urothelial variants included bilateral simple ureteroceles and rightsided complete duplicated collecting system. CONCLUSION: 16-MDCT angiography and urography allow confident detection and classification of a variety of anatomic and incidental anomalies relevant to the preoperative selection of potential laparoscopic renal donors and to surgical planning.

Adolescent↗
PubMed1989

Leprosy in children: correlation of clinical, histopathological, bacteriological and immunological parameters.

The study of leprosy in children has indicated an incidence of 10% amongst leprosy patients attending the clinic. The duration of the disease was usually less than 2 years. The expression of leprosy in this group was either a macule and/or a plaque. Classification was, therefore, different and conforms to indeterminate (I), borderline tuberculoid (BT) and borderline (BB) leprosy. Only occasionally were other clinical variants seen. The bacteriology was largely unproductive by slit-skin smears. The lepromin (Mitsuda) responses were positive in BT and unpredictable in BB patients. Epicutaneous responses to sensitization with dinitrochlorobenzene (DNCB) paralleled responses to lepromin. Microscopic pathology was of very little help. The correlation of these parameters was only 50-60% indicating that the diagnosis of leprosy should primarily be based on clinical features.

Adolescent↗