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At least 1,333 records · Page 74Linked to original sources
PubMed2006

Systematic significance of seed morphology in veronica (plantaginaceae): a phylogenetic perspective.

BACKGROUND AND AIMS: A new infrageneric rearrangement for Veronica has been proposed based on the most recent evidence from DNA sequence data, morphological evidence, and biogeographical considerations. Looking for morphological synapomorphies for each monophyletic subgenus has been problematic, due to difficulties arising from widespread homoplasy (mainly parallel evolution). In an attempt to overcome these difficulties, previously underexplored morphological characters are starting to be studied in more depth. METHODS: A molecular phylogenetic hypothesis was used based on sequences of ITS (nuclear ribosomal DNA) and plastid trnL-F regions, as a framework to test the use of seed coat ultrastructure (studied under scanning electron microscope) in the systematics of the genus. A sample of 132 taxa representing ten of the 13 subgenera in Veronica, excluding the species of the southern hemisphere Hebe complex and the exclusively North American subgenus Synthyris, was studied. KEY RESULTS AND CONCLUSIONS: The results demonstrate that, in many cases, the ultrastucture of the testa can be employed to assess relationships of taxa within the genus, and the character provides additional support for molecular trees. Further characters relevant for the classification of Veronica, i.e. base chromosome number, iridoid chemical data, life cycle, inflorescence position, have been taken into consideration in a discussion where an attempt is made to highlight the best traits to characterize each subgenus investigated.

Classification↗
PubMed1991

Altered gene expression and oncogenesis of B-cell neoplasia.

B-cell malignancies reveal a number of consistent translocations involving the C-MYC, BCL and IG genes. In common, these rearrangements usually lead to an inability of the involved B-cells to respond to normal regulatory controls for expression of the genes. This usually lead to over-production of the protein products of the genes at inappropriate times of the cell growth cycle and appears to allow a survival advantage to the B-cell. The result of these changes almost certainly plays a prominent role in the development of B-cell neoplasia. Classification of these lymphoma's at a molecular level may be of benefit to determine the prognosis and treatment in addition to providing a useful marker of disease. Determining the molecular basis of these B-cell lymphomas may help our understanding of their pathogenesis. This in turn could lead to more rational treatment aimed at altering the abnormal molecular changes and returning the neoplastic cells to normal cell development.

Chromosomes, Human, Pair 11↗
PubMed2006

Genomic progress in pediatric arthritis: recent work and future goals.

PURPOSE OF REVIEW: Pediatric arthritis is a heterogeneous group of chronic arthropathies that are influenced by complex genetic and perhaps environmental factors. Interacting genetic traits may one day be identified that provide the basis for predicting disease risk and other characteristics such as course, age of onset, and disease severity. The purpose of this review is to describe the recent progress towards identifying the multiple genes related to pediatric arthritis and understand how they relate to each other and to disease pathology. RECENT FINDINGS: Candidate gene studies are by far the most widely reported type of genetic studies to date for juvenile arthritis with only one genome-wide screen for juvenile rheumatoid/idiopathic arthritis published. Particular attention is paid to studies of candidate genes with potential immunological roles and those associated with other forms of autoimmunity. SUMMARY: Genomic studies may perhaps one day provide information to allow future classification systems of childhood arthritis to include molecular biomarkers as a complement to clinical observations, as well as understand how these genes or proteins relate to each other and to disease pathogenesis.

Adolescent↗
PubMed2004

Subclassification of ovarian surface epithelial tumors based on correlation of histologic and molecular pathologic data.

Surface epithelial tumors are a large and heterogeneous group of neoplasms that are subclassified based on cell type and malignant potential. The objective of this review is to examine the correlations between recent molecular pathology data and the traditional histopathologic classification of surface epithelial tumors. By doing so, 6 distinct subsets of ovarian epithelial neoplasia can be identified with potential treatment implications 1. high-grade serous, high-grade endometrioid, and undifferentiated carcinomas; 2. low-grade serous carcinomas and serous borderline tumors; 3. mucinous carcinomas and mucinous borderline tumors of intestinal type; 4. low-grade endometrioid carcinomas and endometrioid borderline tumors; 5. clear cell carcinomas; and 6. transitional cell carcinomas.

Carcinoma↗
PubMed2004

Abnormal blood lactate accumulation after exercise in patients with multiple mitochondrial DNA deletions and minor muscular symptoms.

STUDY OBJECTIVES: Muscle is one of the most commonly affected organs in mitochondrial disorders, and the symptoms are often exercise related. The cardiopulmonary exercise test with the determination of lactic acid formation could give supplementary information about the exercise-induced metabolic stress and compensatory mechanisms used in these disorders. The aim of this study was to evaluate the exercise capacity and lactate kinetics related to exercise in subjects with two genetically characterized mitochondrial disorders (multiple mitochondrial DNA deletions with PEO, MELAS) compared with lactate kinetics in subjects with metabolic myopathy (McArdle's disease) and in the healthy controls. DESIGN: The subjects were consecutive, co-operative patients of Department of Neurology of Helsinki University Hospital. Molecular genetic analyses were used for group classification of the mitochondrial myopathy. STUDY SUBJECTS: The study groups consisted of 11 patients with multiple deletions (PEO) and five patients with a point mutation in the mitochondrial DNA (MELAS), four patients with a muscle phosphorylase enzyme deficiency (McArdle's disease) and 13 healthy controls. The clinical disease of the patients was relatively mild. MEASUREMENTS AND RESULTS: A graded exercise test with ventilatory gas analyses and venous blood lactic acid analyses was performed. The main finding was the prolonged accumulation of blood lactate after the exercise in the PEO and MELAS groups compared with the controls. An overcompensation in ventilation was found in the MELAS and PEO group. CONCLUSIONS: The blood lactate accumulation after exercise occurs in patients with multiple mitochondrial DNA deletions or MELAS even in patients with only mild exercise intolerance. Cardiopulmonary exercise can be used in the diagnostic process of patients with mitochondrial myopathies.

Adult↗
PubMed2006

Contemporary definitions and classification of the cardiomyopathies: an American Heart Association Scientific Statement from the Council on Clinical Cardiology, Heart Failure and Transplantation Committee; Quality of Care and Outcomes Research and Functional Genomics and Translational Biology Interdisciplinary Working Groups; and Council on Epidemiology and Prevention.

Classifications of heart muscle diseases have proved to be exceedingly complex and in many respects contradictory. Indeed, the precise language used to describe these diseases is profoundly important. A new contemporary and rigorous classification of cardiomyopathies (with definitions) is proposed here. This reference document affords an important framework and measure of clarity to this heterogeneous group of diseases. Of particular note, the present classification scheme recognizes the rapid evolution of molecular genetics in cardiology, as well as the introduction of several recently described diseases, and is unique in that it incorporates ion channelopathies as a primary cardiomyopathy.

American Heart Association↗
PubMed2025

Algorithms and tools for data-driven omics integration to achieve multilayer biological insights: a narrative review.

Systems biology is a holistic approach to biological sciences that combines experimental and computational strategies, aimed at integrating information from different scales of biological processes to unravel pathophysiological mechanisms and behaviours. In this scenario, high-throughput technologies have been playing a major role in providing huge amounts of omics data, whose integration would offer unprecedented possibilities in gaining insights on diseases and identifying potential biomarkers. In the present review, we focus on strategies that have been applied in literature to integrate genomics, transcriptomics, proteomics, and metabolomics in the year range 2018-2024. Integration approaches were divided into three main categories: statistical-based approaches, multivariate methods, and machine learning/artificial intelligence techniques. Among them, statistical approaches (mainly based on correlation) were the ones with a slightly higher prevalence, followed by multivariate approaches, and machine learning techniques. Integrating multiple biological layers has shown great potential in uncovering molecular mechanisms, identifying putative biomarkers, and aid classification, most of the time resulting in better performances when compared to single omics analyses. However, significant challenges remain. The high-throughput nature of omics platforms introduces issues such as variable data quality, missing values, collinearity, and dimensionality. These challenges further increase when combining multiple omics datasets, as the complexity and heterogeneity of the data increase with integration. We report different strategies that have been found in literature to cope with these challenges, but some open issues still remain and should be addressed to disclose the full potential of omics integration.

Algorithms↗
PubMed2000

Origin of an ovarian steroid cell tumor causing isosexual pseudoprecocious puberty demonstrated by the expression of adrenal steroidogenic enzymes and adrenocorticotropin receptor.

Ovarian steroid cell tumors are rare neoplasms composed of typical steroid hormone-secreting cells. Most ovarian steroid cell tumors, however, cannot be appropriately classified on a morphological basis, because the neoplastic cells closely resemble adrenal cortical cells. Nevertheless, the true adrenal origin of such tumors has been difficult to demonstrate. Here we report a 3-yr-old girl with isosexual pseudoprecocious puberty due to an ovarian steroid tumor whose adrenal cell origin was determined by the presence of messenger ribonucleic acid (mRNA) of adrenal-specific steroidogenic P450 enzymes (P450c11 and P450c21) and ACTH receptor (ACTHR). Her height was +2.3 SD, and she had Tanner stage III breast development, Tanner stage II pubic hair, and a normal clitoris. Bone age was 5 yr. Basal gonadotropin levels were undetectable (<0.6 U/L for LH and <1.0 U/L for FSH) and remained undetectable after stimulation with 100 microg GnRH, i.v. Basal serum testosterone and 17-hydroxyprogesterone levels were slightly elevated, whereas basal serum androstenedione, estradiol, and dehydroepiandrosterone sulfate levels were clearly elevated. Pelvic ultrasound disclosed an enlarged uterus and an adnexal multicystic mass in the right ovary, and pathological studies disclosed an ovarian steroid cell tumor. To establish the cellular origin of the tumor we determined the presence of mRNA for P450c11, P450c21, and ACTHR in tumor tissue and normal adrenal and ovarian tissue. Detection of ACTHR, P450c21, and P450c11 mRNAs isoforms was achieved in tumoral and adrenal control tissue, but not in the ovary control tissue. The RT-PCR products of P450c11 from adrenal control tissue were composed by both BglI-sensitive and -resistant complementary DNAs, indicating the presence of both P450c11AS and P450c11beta, whereas RT-PCR product from the tumor was resistant to BglI digestion, indicating only the presence of P450c11beta. We conclude that the histological origin of so-called adrenal rest tumor could be reliably determined by assessing the expression of specific genes in the tumor as P450c11beta and P450c21. The use ofthese molecular tools will allow a more precise classification of an important subset of the ovarian steroid cell tumors and can help to identify ectopic adrenal tissue in ovary and testis.

Adrenal Glands↗
PubMed2003

Molecular biology of glioma tumorigenesis.

Gliomas are the most common intracranial malignant tumors in humans, and high-grade gliomas in particular pose a unique challenge due to their propensity for proliferation and tissue invasion. Our understanding of glioma oncogenesis, proliferation, and invasion has been greatly advanced in the past 10 years as researchers have gained a better understanding of the molecular biology of these tumors. This article highlights glioma histopathology, as well as cytogenetic and molecular alterations associated with the pathogenesis of human gliomas. It is hoped that better understanding of the molecular pathogenesis of gliomas will improve tumor classification as well as lead to novel targets for therapy and prognostic markers.

Astrocytoma↗
PubMedDate not supplied

Genomic relations among two non-mangrove and nine mangrove species of Indian Rhizophoraceae.

Random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) markers were used to study the genomic relationship among 11 members of Indian Rhizophoraceae represented by nine true mangroves and two non-mangrove species. The AFLP and RAPD bands were scored and analyzed for genetic similarities and cluster analysis was done which separated the 11 species studied into two main groups, the true mangroves and the non-mangroves. The polymorphism observed for these markers showed a high degree of genetic diversity among the constituent taxa of the family. The phylogenetic relationship inferred from molecular marker systems supported the traditional taxonomic classification of the family Rhizophoraceae based on morphological characters at the levels of tribe, phylogeny and delimitation of genera and species, except the intra-generic classification of the genus Bruguiera and the placement of Rhizophora in the family Rhizophoraceae.

Base Sequence↗
PubMed2026

Proteomic insights into azoospermia: protein differences in testicular tissue between non-obstructive and obstructive azoospermia patients.

Non-obstructive azoospermia (NOA) and obstructive azoospermia (OA) are the main classifications of severe male infertility, but the molecular mechanism of NOA remains poorly understood. This study aimed to identify potential biomarkers and pathological mechanisms by comparing the proteomic differences in testicular tissues of NOA and OA patients. Through proteomic analysis based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) of testicular samples from 5 NOA patients and 5 OA patients, we identified 5264 proteins, among which 717 differentially expressed proteins (DEPs) were found between the two groups (242 upregulated and 475 downregulated in NOA). Bioinformatics analysis indicated that these DEPs were significantly associated with reproductive development, gametogenesis, and cell structural stability. On the basis of this, six candidate proteins, including dysferlin (DYSF), myoferlin (MYOF), mitsugumin 53 (MG53), cluster of differentiation 63 (CD63), caveolin-3 (CAV3), and calpain-3 (CAPN3), were selected from the DEPs and verified in an expanded sample set (37 NOA cases and 28 OA cases) through quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, confirming their dysregulation in NOA. These findings provide new proteomic insights into NOA, highlighting the disruption of membrane repair and structural pathways, and offer potential biomarkers for understanding its pathogenesis.

Humans↗
PubMed2000

[Comparative evaluation of bacteria identification from the Acinetobacter genus using a commercially available API 20NE system, PCR and RFLP techniques].

A study was carried out for identification of 50 Acinetobacter strains isolated from various clinical materials. Using classic methods the following species were identifies: Acinetobacter sp. (68%), Acinetobacter baumanii (24%) and Acinetobacter lwofii (8%). In all strains the recA gene was found of 435-500 pz size which confirms their belonging to that genus. Amplification products were digested with restriction enzymes Mbol and HinfI (RFLP) and their detection was carried out on agarose gel by electrophoresis methods, owing to that the arrangement of gene fragment characteristic of each strain was obtained. After careful analysis restriction patterns were obtained corresponding to the following genome species: Acinetobacter baumanii (60%), Acinetobacter sp. 3 (28%) and Acinetobacter lwoffii (12%). The methods of molecular biology made possible a more precise classification of the studied strains according to species. Certain strains determined as Acinetobacter sp. by the API 20NE system were found to be Acinetobacter baumanii, Acinetobacter sp. 3 or Acinetobacter lwofii when determined by the PCR/RFLP method.

Acinetobacter↗
PubMed2002

Role of genomics in identifying new targets for cancer therapy.

The detailed map of the human genome can potentially transform future cancer therapy by merging genomics with pharmacology, thereby identifying which patients will benefit from specific therapeutic agents. Single-nucleotide polymorphisms (SNPs) provide a valuable tool for this pharmacogenetic approach to cancer therapy. The discovery of SNPs as disease markers may facilitate identification of populations at increased risk for certain cancers. In addition, SNP genetic screening may facilitate administration of appropriate treatment modalities or reveal specific genetic profiles that have importance in drug efficacy and toxicity. In addition to SNP analysis, DNA and tissue microarray analyses have the potential to transform the future of cancer therapy. For example, DNA microarrays may improve tumor classification systems as well as provide a molecular level dissection of global gene expression changes that occur in carcinogenesis. Tissue microarrays would allow one to verify candidate genes, identified from DNA microarrays, against archival tumor specimens with known clinical outcome. In addition, both microarray technologies may be combined to rapidly validate gene targets. We will review and discuss these state-of-the-art technologies including data suggesting that the combined use of these high throughput technologies will facilitate our understanding of the genetic complexities inherent in cancer and will revolutionize cancer therapy.

Drug Design↗
PubMed2006

[Ionic channels and currents in the cardiomyocytes.].

Review concerns modern views on ionic mechanism of action potential formation in cardiomyocytes. Main characteristics of cardiomyocyte ion current are described. Importance of ion current in formation of action potential phases in various regions of the heart is considered. Molecular structure and up-to-date classification of ion channels are presented. Number of genetic abnormalities which lead to appearance of arrhythmias are described.

Action Potentials↗
PubMed1983

Characterization of glycosphingolipids from cells of various types of human leukemia: occurrence of two glycosphingolipids, one reacting with anti-asialo GM1 antibody and one with anti-Forssman antibody.

Glycosphingolipids of neutrophils, lymphocytes and leukocytes from patients with various types of human leukemia [acute lymphoblastic (ALL), acute unclassified type (AUL), acute myeloblastic (AML), acute monocytic (AMoL), chronic myeloblastic (CML)] and the hypereosinophilic syndrome (HES) were analyzed chemically and immunochemically. No distinct difference was found in the molar ratio of lipid-bound sialic acid to lipid-bound phosphorus in these cells, but a low ratio of cholesterol to lipid-bound phosphorus was found in ALL (3 of 4 cases), AML, CML and AMoL (one of 2 cases). The predominant glycosphingolipid was ceramide dihexoside (CDH) in all cells analyzed, but the amount and the molar ratio of lipid-bound phosphorus to CDH were clearly different in different cell types, indicating that the molar ratio is a useful criterion in the classification of types of leukemia. In addition, molecular diversity of minor glycosphingolipid components was observed in various leukemic cells. Two of the neutral glycosphingolipids in AMoL were tentatively identified as asialo GM1 and Forssman glycolipids by comparing their mobilities on thin-layer chromatography with those of standard glycolipids and by observing the formation of precipitin lines on a double diffusion agar plate with anti-asialo GM1 and anti-Forssman antibodies.

G(M1) Ganglioside↗
PubMed1993

Trypanosoma cruzi ribosomal RNA genes: a review.

Our research work group has been interested in the study of the ribosomal RNA and 5S gene systems from Trypanosoma cruzi. Our contributions span from the general description of a multifragmented molecular system, to the sequence analysis of some ribosomal RNA coding regions. From the latter, we have constructed phylogenetic trees of the Trypanosomatidae family, and our data indicate that the molecular inferences do not sustain the traditional classification of these species. Our published findings are here reviewed along with recent unpublished observations of ribosomal RNA and 5S gene structures.

Animals↗
PubMed1993

Macrophage inflammatory protein: its characteristics, biological properties and role in the regulation of haemopoiesis.

Studies on haemopoietic stem cells had led to the realisation that negative feedback inhibitors play an important role in regulating their proliferation. One such molecule was identified as MIP-1 alpha. One of a family of cytokines, originally recognised as inflammatory molecules, MIP-1 alpha is now potentially valuable as a means of manipulating and protecting haemopoietic (and possibly other) stem cells during chemotherapy. This short review briefly considers the structural classification of MIP-1 alpha and its molecular relatives and indicates some of the probable human/murine equivalent molecules outlining the evidence for the equivalence of MIP-1 alpha (murine) and LD78 (human). Sources of MIP-1 alpha/LD78 are identified as monocyte/macrophage and lymphocytic cells and their role in inflammatory responses is seen to be significant. All proliferation in haemopoietic tissue is now recognised as a major target for MIP-1 alpha action. In vitro it synergises with certain growth factors to promote progenitor cell colony formation, but effects are dependent on the maturational age of the cells promoted. With more primitive cells it is seen as inhibitory. This property is particularly valuable in vivo where MIP-1 alpha can protect stem cells against the effects of cytotoxic agents. Since it appears that leukaemic stem cell proliferation is not inhibited, MIP-1 alpha/LD78 present great potential for stem cell protection in the theatre of cytotoxic therapies.

Animals↗
PubMed1993

Experimental murine chronic hepatitis: results following intrahepatic inoculation of human uveitis mycoplasma-like organisms.

Mycoplasma-like organisms (MLO) are non-cultivated intracellular cell-wall deficient pathogenic bacteria with a distinctive ultrastructural appearance. Diagnosis of MLO disease depends on finding the organisms in parasitized cells using a transmission electron microscope. MLO are a well studied cause of transmissible chronic plant disease responsive to antibiotics. MLO have recently been found to cause human chronic uveitis, orbital, and retinal disease with autoimmune features. Ophthalmic leucocytes in these patients display MLO parasitization. Inoculation of human uveitis MLO into mouse eyelids produced chronic uveitis. MLO also disseminated to produce randomly distributed lethal systemic disease including chronic hepatitis. MLO parasitized leucocytes were present in all disease sites. Direct intrahepatic inoculation of human hepatic pathogens is a simple and efficient technique to produce murine hepatitis. This report describes the delayed onset widespread inflammatory liver disease produced by direct intrahepatic inoculation of human chronic uveitis MLO in 12 of 20 mice versus 0 in 40 controls (P < 0.05). The liver disease was accompanied by elevated serum SGOT levels, splenomegaly, and accelerated mortality. All 12 inflamed livers displayed MLO parasitized leucocytes versus 0 of 10 control livers. The resemblance of human chronic active hepatitis, massive hepatic necrosis, and post-necrotic cirrhosis to the MLO induced murine liver disease, the role of molecular biologic techniques in the detection and classification of those bacteria, and in therapy of MLO disease are discussed.

Animals↗