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PubMed1995

Degos syndrome: malignant atrophic papulosis.

Malignant atrophic papulosis is a rare disorder characterized by pathognomonic cutaneous lesions that have been associated with multiple infarctive thrombotic lesions of other viscera, most notably the gastrointestinal tract and the central nervous system. Systemic involvement may develop from weeks to years after the onset of the characteristic cutaneous lesions or, rarely, may precede the cutaneous lesions. However, the existence of patients with a prolonged, purely cutaneous variant of this disease has been increasingly appreciated, and this brings into question the appropriateness of applying the term "malignant" to all patients who have the peculiar characteristic cutaneous lesions of malignant atrophic papulosis. Despite half a century of sporadic investigation, the precise cause of this disease remains unknown, and accurate classification of this entity as a primary vasculopathy or primary coagulopathy has not been possible. Unfortunately, no effective therapy exists for those patients in whom systemic involvement develops.

Adult↗

PubMed2003

Pathologic classification of focal segmental glomerulosclerosis.

Focal segmental glomerulosclerosis (FSGS) is defined as a clinical-pathologic syndrome manifesting proteinuria and focal and segmental glomerular sclerosis with foot process effacement. The pathologic approach to the classification of FSGS is complicated by the existence of primary (idiopathic) forms and multiple subcategories with etiologic associations, including human immunodeficiency virus (HIV)-associated nephropathy, heroin nephropathy, familial forms, drug toxicities, and a large group of secondary FSGS mediated by structural-functional adaptations to glomerular hyperfiltration. A number of morphologic variants of primary and secondary focal sclerosis are now recognized, including FSGS not otherwise specified (NOS), perihilar, cellular, tip, and collapsing variants. The defining features of these morphologic variants and of the major subcategories of FSGS are discussed with emphasis on distinguishing light microscopic patterns and clinical-pathologic correlations.

Disease Progression↗

PubMed2000

Mycosis fungoides d'embleé: CD30-negative cutaneous large T-cell lymphoma.

The d'embleé variant of mycosis fungoides initially described patients with a rapid onset of tumors without progression through patch- and plaque-stage disease. We report a case of a patient with the clinical presentation of mycosis fungoides d'embleé and correlate the histologic and immunophenotypic data with those of a more updated classification scheme.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2006

Protein solubility: sequence based prediction and experimental verification.

MOTIVATION: Obtaining soluble proteins in sufficient concentrations is a recurring limiting factor in various experimental studies. Solubility is an individual trait of proteins which, under a given set of experimental conditions, is determined by their amino acid sequence. Accurate theoretical prediction of solubility from sequence is instrumental for setting priorities on targets in large-scale proteomics projects. RESULTS: We present a machine-learning approach called PROSO to assess the chance of a protein to be soluble upon heterologous expression in Escherichia coli based on its amino acid composition. The classification algorithm is organized as a two-layered structure in which the output of primary support vector machine (SVM) classifiers serves as input for a secondary Naive Bayes classifier. Experimental progress information from the TargetDB database as well as previously published datasets were used as the source of training data. In comparison with previously published methods our classification algorithm possesses improved discriminatory capacity characterized by the Matthews Correlation Coefficient (MCC) of 0.434 between predicted and known solubility states and the overall prediction accuracy of 72% (75 and 68% for positive and negative class, respectively). We also provide experimental verification of our predictions using solubility measurements for 31 mutational variants of two different proteins.

Amino Acid Sequence↗

PubMed2025

A paradoxical population structure of var DBLα types in Africa.

The var multigene family encodes Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), central to host-parasite interactions. Genome structure studies have identified three major groups of var genes by specific upstream sequences (upsA, B, or C). Var with these ups groups have different chromosomal locations, transcriptional directions, and associations with disease severity. Here we explore temporal and spatial diversity of a region of var genes encoding the DBLα domain of PfEMP1 in Africa. By applying a novel ups classification algorithm (cUps) to publicly-available DBLα sequence datasets, we categorised DBLα according to association with the three ups groups, thereby avoiding the need to sequence complete genes. Data from deep sequencing of DBLα types in a local population in northern Ghana surveyed seven times from 2012 to 2017 found variants with rare-to-moderate-to-extreme frequencies, and the common variants were temporally stable in this local endemic area. Furthermore, we observed that every isolate repertoire, whether mono- or multiclonal, comprised DBLα types occurring with these frequency ranges implying a common genome structure. When comparing African countries of Ghana, Gabon, Malawi, and Uganda, we report that some DBLα types were consistently found at high frequencies in multiple African countries while others were common only at the country level. The implication of these local and pan-Africa population patterns is discussed in terms of advantage to the parasite with regards to within-host adaptation and resilience to malaria control.

Plasmodium falciparum↗

PubMed2002

Clinical utility of CD23 and FMC7 antigen coexistent expression in B-cell lymphoproliferative disorder subclassification.

BACKGROUND: CD23 and FMC7 are normal B-cell antigens utilized during diagnostic immunophenotyping of suspected lymphoproliferative disorders. However, the diagnostic utility of coexistent antigenic expression patterns with simultaneous two-color staining and flow cytometric analysis has not been studied extensively. METHODS: Using multiparameter flow cytometry, we evaluated the expression pattern of FMC7 and CD23 in 218 cases of B-cell lymphoma from blood and bone marrow specimens. RESULTS: The CD23(+)/FMC7(-) pattern was the most common pattern in patients with chronic lymphocytic leukemia and related variants. The widest variation of patterns was found in patients with follicular cell lymphoma, large cell lymphoma, and Waldenström's macroglobulinemia, a lymphoplasmacytoid disorder, although most cases expressed the CD23-/FMC7(+) pattern. The CD23 and FMC7 antigen, along with the CD5 coexpression pattern, provides critical adjunctive data. These data allow accurate classification of the majority of cases, thereby providing a key aspect of a reliable diagnostic algorithm. The CD23 and FMC7 antigen expression pattern, along with selected other antigens, was predictive of subtypes in >95% of lymphoproliferative cases and narrowed the differential diagnosis in the remaining cases. CONCLUSION: The flow cytometric CD23/FMC7 expression pattern achieved by multicolor immunophenotyping facilitates accurate and reproducible classification of B-cell lymphomas and has diagnostic utility.

Algorithms↗

PubMed1990

[Histologic aspects of seborrheic keratosis].

The histopathological aspects of seborrheic keratosis have been studied in order to establish a basis to their classification upon structural morphology and cytology. The 210 seborrheic keratosis studied could be classified in several patterns among which we must point out the three most important ones: hyperkeratotic, adenoid and acanthotic. This last one can offer two very different images: uniform acanthotic (this one including at the same time, a variant of "small basal cells") and reticular acanthotic. Special mention has to be made as well to the activated and pure forms which, though being the result of evolutive accidental phenomena, no doubt they have very particular and distinctive histopathological aspects. Further, other variants are discussed such a clonal and acantholytic seborrheic keratosis, as well as the significance of inverted follicular keratosis and of melanoacanthoma.

Dermatitis, Seborrheic↗

PubMedDate not supplied

Molecular epidemiology of DNA viruses: applications of restriction endonuclease cleavage site analysis.

Restriction endonucleases which cleave DNA at specific nucleotide sequences can be used to produce a set of DNA fragments of a viral genome which, when separated by gel electrophoresis, gives a characteristic "fingerprint" for that virus genome. This simple technique has been used to identify and classify DNA viruses of the herpes, adeno, and papova virus groups. Small variants within a given type (e.g., herpes simplex type I) are genetically stable and permit study and identification of individual strains of viruses. Such analyses have recently been applied to study the epidemiology of some DNA virus outbreaks. Restriction endonuclease fingerprinting provides a useful addition to methods for virus identification and classification.

Cytomegalovirus↗

PubMed2002

Renal epithelial neoplasms: the diagnostic implications of electron microscopic study in 55 cases.

Several unsettled histogenetic, nosologic and diagnostic considerations for renal epithelial tumors may have ultrastructural ramifications. Yet, a comprehensive electron microscopic study of renal epithelial neoplasms, in light of the recent classification, is not available. The ultrastructural findings from fifty-five renal epithelial neoplasms [31 clear cell renal cell carcinomas (RCC), 11 papillary RCC, 5 chromophobe RCC, 3 sarcomatoid RCC and 5 oncocytomas] were correlated with their light microscopic appearance. Clear cell RCC showed long microvilli similar to the brush border of the normal proximal tubules, with abundant cytoplasmic lipid and glycogen. Papillary RCC showed variably sized microvilli, and small amounts of cytoplasmic lipid, but no glycogen. Chromophobe RCC showed many cytoplasmic vesicles and abnormal mitochondria, with rare short and stubby microvilli. Renal oncocytoma showed many mitochondria with a few vesicles in the apical portion of the cytoplasm and rare short and stubby microvilli. The eosinophilic cell variants of clear cell RCC, papillary RCC and chromophobe RCC showed ultrastructural features similar to those of their respective prototypes, except for an increased numbers of mitochondria in the cytoplasm. One sarcomatoid clear cell RCC showed skeletal muscle differentiation. Two types of cytoplasmic inclusions, i.e. hyaline globules and granules similar to those in the Paneth cells (PC-like granules) were identified only in clear cell RCC, which displayed distinctive ultrastructural features. The current EM study demonstrates distinctive ultrastructural features of renal epithelial neoplasms. The findings lend additional support to the current classification of the pertinent tumor types, facilitate the differential diagnoses, and provide insights into the possible histogenesis of renal epithelial neoplasms.

Adenoma, Oxyphilic↗

PubMed1992

Analysis of chronic lymphoid leukaemias according to FAB.

We have studied the immunophenotypic features in patients with chronic lymphoid leukaemia and investigated the suitability of classification according to guidelines of the French-American-British (FAB) group. Immunophenotyping was carried out on cytocentrifuge preparations of mononuclear blood leukocytes using the alkaline phosphatase-antialkaline phosphatase (APAAP) method. The 114 leukaemias, including 58 cases of B-chronic lymphocytic leukaemia (B-CLL), 3 Waldenström's macroglobulinaemia, 6 prolymphocytic leukaemia (B-PL), 13 B-CLL/PL, 4 B-CLL of mixed cell type, 8 splenic lymphoma with villous lymphocytes (SLVL), 8 hairy cell leukaemia (HCL), two HCL variant, three leukaemic phase of follicular lymphoma, two leukaemic phase of intermediate lymphoma, two plasma cell leukaemia and two chronic T-cell leukaemia, were investigated. The 111 of 112 B-chronic lymphoid leukaemias (B-CLL + B-PL + B-CLL/PL + SLVL + HCL etc.) showed monotypic light chains. The antibody HML1 was highly specific for HCL. The antibodies CD11c and CD25 were positive in all HCL cases, but were not specific for this disease. CD5 positivity and CD22s negativity were found in most patients with B-CLL, B-CLL/PL and B-CLL of mixed type. This marker type has a limited value for differentiation from the other chronic lymphoid leukaemias. We also studied three patients with chronic lymphoid leukaemia which were not described by the FAB classification. We conclude that a study of the morphology of the leukaemic cells was the most useful basis for the diagnosis of these leukaemias, whereas immunotyping was apparently valuable only in individual cases.

Antigens, CD↗

PubMed1990

Cytoplasmic male sterility in beta is associated with structural rearrangements of the mitochondrial DNA and is not due to interspecific organelle transfer.

Chloroplast (ct) and mitochondrial (mt) DNAs from four cytoplasmic male sterile (cms) and 22 normal fertile sugar beet lines and accessions of wild beets from the genus Beta have been compared with restriction analyses and Southern hybridizations. We have used restriction analyses of ctDNA as a phylogenetic marker to confirm the taxonomic relationships between the different cytoplasms. According to the ctDNA data, all four cms cytoplasms belong to the same taxonomic section, Beta. Restriction patterns of ct and mtDNA from fertile accessions produced analogous trees of similarity and showed a close correlation between the organellar DNA diversity and the accepted taxonomic classification of the species studied. However, the mt-DNA restriction profiles of the four cms types differed dramatically from each other and from those of all fertile accessions from the genus. No indication of cytoplasmic introgression was found in any of the four investigated cms types. Southern hybridization to mtDNA revealed variant genomic arrangements in the different fertile and cms cytoplasms, indicating that rearrangement of the mitochondrial genome is a common denominator to the different cms systems in Beta. It may, indeed, be a common property to spontaneously occurring cms in all or most species.

Chloroplasts↗

PubMed2004

Genotypic resistance and HIV-1 subtype in Brazilian children on dual and triple combination therapy.

BACKGROUND: Antiretroviral therapy is provided by the Brazilian Ministry of Health to eligible HIV-infected individuals. Based on clinical and immunological classification, the Brazilian guidelines recommend dual or triple therapy for children. However, the development of drug-resistant strains or poor adherence to therapy could impact the efficacy of this approach. OBJECTIVES: We examined relationships between RNA levels, CD4+ T-cell counts, treatment history, and the prevalence of drug-resistant variants in a cohort of HIV-1-infected children in Rio de Janeiro, Brazil. STUDY DESIGN: Direct sequencing of reverse transcriptase and protease genes from plasma was performed. Virologic and CD4+ T-cell counts responses to therapy were assessed by changes in HIV-1 RNA levels and CD4+ T-cell counts from baseline. RESULTS: Thirty-seven patients were receiving dual therapy and 38 were on triple therapy at enrollment, segregated by antiretroviral history. Both groups had a higher increase in CD4+ T cell counts and a lower viral load in pre-treatment antiretroviral-naïve subjects. Notably, there was a direct correlation between the higher frequencies of drug-resistance mutations and cross-resistance with previous usage of antiretroviral (ARV) therapy in both groups. Non-B subtypes isolates were found in 21.3% of samples. A smaller increase in CD4+ T cell counts was found between non-B subtypes when compared to B-subtypes. CONCLUSIONS: These results suggest that less immunological recovery and a higher number of mutations related to drug resistance were associated with previous usage of ARV and consequent higher time under drug selective pressure in these HIV-infected Brazilian children. These facts suggest the preferential use of triple drug combination as first line regimen in children.

Adolescent↗

PubMed1988

Diagnosis and grading of chronic pancreatitis by morphological criteria derived by ultrasound and pancreatography.

The most commonly used modalities in the diagnosis of chronic pancreatitis are ultrasonography, computed tomography (CT) and endoscopic retrograde pancreatography (ERP). Computed tomography scanning is only of value in severe chronic pancreatitis. Both ultrasound and pancreatography are capable of showing ductal changes in mild forms of the disease, but comparison of the two methods has been difficult. A scheme of morphological criteria and descriptive terminology of pancreatitis was applied to 58 out of 85 patients with a firm clinical diagnosis of chronic pancreatitis. Twenty-seven patients were excluded from the study, four with a faulty clinical diagnosis and 23 with non-diagnostic pancreatograms. There was an exact classification into normal, equivocal, mild, moderate or marked chronic pancreatitis in 50 out of 58 patients (86%) and an almost perfect correlation (+ or - one grade) in 54 out of 58 (93%). There were four discrepancies. Ultrasound examination missed focal pancreatitis in the tail, a small cavity in the uncinate process and a variant of chronic pancreatitis. One ultrasound scan was of poor quality. Morphological grading by different techniques is feasible and use of this scheme can reduce diagnosis to a simple and specific set of rules.

Cholangiopancreatography, Endoscopic Retrograde↗

PubMed1996

Renal vasculitis.

The term 'vasculitides' encompasses a group of inflammatory disorders which may affect the kidney by damaging its blood supply. Although the kidney may be affected by many types of systemic vasculitis, renal involvement is particularly frequent in some forms of systemic necrotizing vasculitis which are considered primary, such as Wegener's granulomatosis and microscopic polyarteritis, including its 'renal-limited' variant. Renal vasculitis can occur at any age, but is seen particularly frequently in middle-aged and elderly subjects, in whom clinical presentation and prognosis are significantly worse. In addition to the specific problems related to age, this review focuses on a few aspects that are still the subjects of debate: classification, the role of ANCA, renal pathology and the treatment of renal vasculitis.

Age Factors↗

PubMedDate not supplied

The spectrum of cutaneous lymphomas in patients less than 20 years of age.

Cutaneous lymphomas are rare in young patients and are mostly represented by mycosis fungoides and its variants and CD30+ lymphoproliferative disorders (lymphomatoid papulosis [LYP] and anaplastic large T-cell lymphoma). We report our observations in a series of 69 patients less than 20 years of age who presented either with primary cutaneous lymphoma (n = 62) or with secondary manifestations of extracutaneous disease (n = 7). Clinicopathologic features permitted classification of the cases into the following diagnostic categories: mycosis fungoides (n = 24, all primary cutaneous), anaplastic large T-cell lymphoma (n = 13, all primary cutaneous), LYP (n = 11, all primary cutaneous), subcutaneous "panniculitis-like" T-cell lymphoma (n = 1, primary cutaneous), small-medium pleomorphic T-cell lymphoma (n = 2, all primary cutaneous), natural killer (NK)/T-cell lymphoma, nasal-type (n = 1, secondary cutaneous), follicle center cell lymphoma (n = 1, primary cutaneous), marginal zone B-cell lymphoma (n = 7, all primary cutaneous), B-lymphoblastic lymphomas (n = 6, 3 primary and 3 secondary cutaneous), specific cutaneous manifestations of Hodgkin disease (n = 1, secondary cutaneous), and acute myeloid leukemia (n = 2, both secondary cutaneous). Cutaneous lymphoma in children should be differentiated from benign skin disorders that may simulate them. In particular, mycosis fungoides and LYP in this age group may present with clinicopathologic features reminiscent of inflammatory disorders such as pityriasis alba, vitiligo, pityriasis rosea, and pityriasis lichenoides et varioliformis acuta. Even in secondary cutaneous lymphomas, skin manifestations may be the first sign of the systemic disease, and a diagnosis may be achieved on examination of histopathologic specimens of a cutaneous lesion. Our study illustrates the wide spectrum of cutaneous lymphomas and leukemias in patients less than 20 years of age and underlines the need for proper interpretation of these lesions by dermatologists and dermatopathologists.

Adolescent↗

PubMed2002

The frequency of different plural renal arteries rare variants.

The aim of this work was to evaluate the frequency of different plural renal arteries rare variants in healthy patients and in many different pathological diseases. Abdominal aortography with following selective angiography was performed on 35 randomly selected patients of Medical Department, with the use of radiopaque and with followed radiological parameters: P--75 kV, I--9 mA, T--10 sec. According to the available literature the following classification was introduced: double renal arteries--two vessels originating from the aorta, similar in diameter, blood supply areas, and their branches entering kidney through hilum (observed in 20% of cases), triple renal arteries--three vessels originating from the aorta with different diameter and blood supply areas, and their branches entering kidney through hilum (observed in 3%), upper pole accessory artery--originates from aorta, diameter of which being comparable to segmental arteries, entering kidney through hilum (6%), lower pole accessory artery (40%), upper pole perforating artery--originates from aorta or one of its major branches, diameter of which being comparable to segmental or subsegmental arteries, supplying one segment only, entering kidney outside of hilum (26%), and lower pole perforating artery (3%).

Angiography↗

PubMed2004

Cutaneous T-cell lymphomas (including rare subtypes). Current concepts. II.

BACKGROUND: Cutaneous T-cell lymphomas (CTCL) represent about the 80% of skin lymphomas and comprise a heterogeneous group of diseases with respect to clinical presentation, outcome, histologic and immunophenotypic features. In the recent years, data have been accumulated indicating that clinical and biological differences exists between primary nodal and primary extranodal lymphomas. INFORMATION SOURCES: On such bases, the cutaneous lymphoma classification by the EORTC (European Organization for Cancer Research and Treatment) but also the recent general lymphoma classification, by the WHO (World Health Organization), have dedicated special attentions to the cutaneous lymphomas including the T and NK-cell subtypes. This paper reviews the most significative subtypes of T-cell lymphoma that affect the skin primarily or secondarily. STATE OF THE ART: Apart from mycosis fungoides with its variants forms and the Sezary's syndrome, we have focused on the CD30+ primary cutaneous lymphoproliferative disorders (PCLD) (25% of all CTCL), a fascinating spectrum of disease, extending from lymphomatoid papulosis (LyP) trough to CD30+ large cell lymphoma. These disorders have in common large atypical CD30+ cells and a frequent spontaneous regression of the skin lesions associated with a relatively favourable outcome (excellent in LyP). The identification of this group of skin disorders is crucial for the patients since most of CD30+ PCLD are indolent diseases that do not warrant aggressive treatment. Others types of CTCL include the heterogeneous category of peripheral T-cell lymphoma not otherwise specified (NOS), subcutaneous panniculitis-like T-cell lymphoma and the still controversial group of the cytotoxic lymphomas. PERSPECTIVES: Notably, the latter two subtypes have special relevance to the clinicians because (i) subcutaneous panniculitis-like T-cell lymphoma may be associated with the hemophagocytic syndrome; (ii) skin lesions in cytotoxic lymphomas may represent the first manifestation of an otherwise systemic disease.

Diagnosis, Differential↗

PubMedDate not supplied

[Differentiated thyroid cancer--staging and prognostic systems].

Differentiated thyroid cancer (DTC), including papillary and follicular carcinoma with histological variants, has an excellent prognosis; nevertheless a subset of these tumours is clinically aggressive and, in some patients, fatal. Treatment of DTC remains controversial, regarding the extent of primary surgical resection, the need for lymph node dissection and the role of postoperative radioactive iodine ablation. In addition to the widely accepted TNM classification, recognition of significant risk factors and developing of staging systems, such as AMES, AGES, MACIS, MSKCC and NTCTCS, has helped to identify the patients with a potential aggressive course of the disease and high risk of recurrence. This has allowed the development of a rational and selective approach to therapy, thus, avoiding excessive treatment and subsequent morbidity without compromising the oncological outcome.

Carcinoma, Papillary↗