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1.
Front Neuroendocrinol ; 65: 100988, 2022 04.
Article in English | MEDLINE | ID: mdl-35202605

ABSTRACT

Endometriosis is a chronic pain disorder that affects young women, impairing their physical, mental and social well-being. Apart from personal suffering, it imposes a significant economic burden on the healthcare system. We analyzed studies reporting comorbid mental disorders in endometriosis based on the ICD/DSM criteria, discussing them in the context of available neuroimaging studies. We postulate that at least one-third of endometriosis patients suffer from mental disorders (mostly depression or anxiety) and require psychiatric or psychotherapeutic support. According to three neuroimaging studies involving patients with endometriosis, brain regions related not only to pain processing but also to emotion, cognition, self-regulation and reward likely constitute the so-called "endometriosis brain". It is not clear, however, whether the neurobiological changes seen in these patients are caused by chronic pain, mental comorbidities or endometriosis itself. Given the paucity of high-quality data on mental comorbidities and neurobiological correlates in endometriosis, further research is needed.


Subject(s)
Chronic Pain , Endometriosis , Anxiety , Brain/diagnostic imaging , Endometriosis/complications , Endometriosis/diagnostic imaging , Endometriosis/epidemiology , Female , Humans , Pelvic Pain/etiology , Pelvic Pain/psychology
2.
Psychoneuroendocrinology ; 125: 105122, 2021 03.
Article in English | MEDLINE | ID: mdl-33421704

ABSTRACT

Pregnancy and the postpartum period are characterized by physiological alterations in cortisol and cortisone levels. In the present study, we sought to explore the risk factors for postpartum depression (PPD) and self-remitting postpartum adjustment disorder (AD) and whether cortisol/cortisone metabolism might have any bearing on them. Hair samples from 196 participants (mean age = 31.44, SD = 4.71) were collected at two time points (1-6 days after childbirth and 12 weeks postpartum) to determine the cumulative hair cortisol (HCC) and hair cortisone (HCNC) exposure in the third trimester and during the 12 weeks postpartum. Compared to the non-depressed group (ND, n = 141), more women in the AD (n = 28) and PPD (n = 27) groups had a personal or family history of depression and more stressful life events. Compared to ND and PPD, more women in the AD group had birth-related complications with their children being more often transferred to a pediatric ward. The factors associated with PPD were found to include being unmarried and having a lower household income, less support at home, more subjectively perceived stress after childbirth and lower maternal sensitivity. The natural decrease in HCC concentration from the third trimester to 12 weeks postpartum was significant only in the ND and AD groups, but not in PPD. In summary, prolonged subjectively perceived postpartum stress associated with living situations may contribute to the development of PPD while birth- and child-related complications are likely to trigger brief episodes of AD. Only in ND and AD, the pregnancy-related physiological changes in glucocorticoid levels return to the pre-pregnancy baseline after 12 weeks. Our observations point to the difference between the ND and PPD groups in glucocorticoid metabolism-related postpartum adjustment, which may be a factor in the development of PPD.


Subject(s)
Cortisone , Depression, Postpartum , Adult , Female , Glucocorticoids , Humans , Hydrocortisone , Postpartum Period , Pregnancy , Risk Factors
3.
J Cell Biol ; 107(3): 1231-9, 1988 Sep.
Article in English | MEDLINE | ID: mdl-3138248

ABSTRACT

The synthetic peptide Gly-Arg-Gly-Asp-Ser (GRGDS) mimics the cellular binding site of many adhesive proteins in the extracellular matrix and causes rounding and detachment of spread cells. We have studied whether its binding affects the associations of two major components, alpha-actinin and vinculin, at the adhesion plaque. Living 3T3 cells were microinjected with fluorescently labeled alpha-actinin and/or vinculin and observed using video microscopy before and after the addition of 50 micrograms/ml GRGDS. As soon as 5 min after treatment, fluorescent alpha-actinin and vinculin became dissociated simultaneously from the sites of many focal contacts. The proteins either moved away as discrete structures or dispersed from adhesion plaques. As a result, the enrichment of alpha-actinin and vinculin at these focal contacts was no longer detected. The focal contacts then faded away slowly without showing detectable movement. These data suggest that the binding state of integrin has a transmembrane effect on the distribution of cytoskeletal components. The dissociation of alpha-actinin and vinculin from adhesion plaques may in turn weaken the contacts and result in rounding and detachment of cells.


Subject(s)
Actinin/metabolism , Antineoplastic Agents/pharmacology , Cell Adhesion/drug effects , Muscle Proteins/metabolism , Oligopeptides/pharmacology , Animals , Cell Line , Extracellular Matrix/drug effects , Extracellular Matrix/metabolism , Microinjections , Microscopy, Fluorescence , Vinculin
4.
J Cell Biol ; 104(6): 1521-6, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3034916

ABSTRACT

Normal rat kidney cells infected with a Rous sarcoma virus (strain LA23) were used to study the dynamics of alpha-actinin-containing aggregates in transformed cells. Experiments were performed by microinjecting living cells with iodoacetamidotetramethylrhodamine alpha-actinin and allowing the fluorescent analogue to incorporate into cellular structures. Subsequent time-lapse recording indicated that the alpha-actinin-containing aggregates can undergo rapid formation, movement, and breakdown. In addition, experiments using the photobleaching recovery technique indicated that alpha-actinin molecules associated with the aggregates have a very high rate of exchange, whereas those associated with adhesion plaques in normal cells exchange much more slowly. The dynamic properties of alpha-actinin-containing aggregates may be closely related to the changes in cellular behavior upon oncogenic transformation.


Subject(s)
Actinin/metabolism , Cell Transformation, Neoplastic , Cell Transformation, Viral , Animals , Avian Sarcoma Viruses/physiology , Cell Adhesion , Cell Line , Microscopy, Fluorescence , Rats
5.
Science ; 260(5106): 340-2, 1993 Apr 16.
Article in English | MEDLINE | ID: mdl-8469985

ABSTRACT

A phylogenetic framework inferred from comparisons of small subunit ribosomal RNA sequences describes the evolutionary origin and early branching patterns of the kingdom Animalia. Maximum likelihood analyses show the animal lineage is monophyletic and includes choanoflagellates. Within the metazoan assemblage, the divergence of sponges is followed by the Ctenophora, the Cnidaria plus the placozoan Trichoplax adhaerens, and finally by an unresolved polychotomy of bilateral animal phyla. From these data, it was inferred that animals and fungi share a unique evolutionary history and that their last common ancestor was a flagellated protist similar to extant choanoflagellates.


Subject(s)
Biological Evolution , Fungi , Phylogeny , RNA, Ribosomal/genetics , Animals , Base Sequence , Ciliophora/genetics , Eukaryota/genetics , Fungi/genetics , Likelihood Functions , Porifera/genetics , RNA, Ribosomal/chemistry
6.
Biol Psychol ; 143: 53-61, 2019 04.
Article in English | MEDLINE | ID: mdl-30797948

ABSTRACT

Prolonged stress affects the central nervous system, rendering individuals vulnerable to a wide range of mental health disorders. 76 healthy postpartum mothers were studied by means of functional magnetic resonance imaging within 6 days of childbirth. The subjects were required to perform the emotional Stroop task involving happy and anxious word-face combinations. Hair samples were collected to determine cumulative hair cortisol concentration (HCC) in the third trimester. HCC was found to be negatively correlated with the recruitment of the dorsal anterior cingulate cortex (ACC) and the midcingulate cortex (MCC). In response to the emotional interference of only anxious target faces, a negative correlation was seen between HCC and the bilateral orbitofrontal cortex, extending to the rostral ACC and the MCC. Women with lower HCC recruited brain areas relevant to emotional cognitive control, indicating that lower HCC helps preserve conflict monitoring and resolution capacities and thus benefits mental health in pregnancy.


Subject(s)
Hydrocortisone/metabolism , Mothers/psychology , Pregnancy Complications/metabolism , Pregnancy Trimester, Third/metabolism , Stress, Psychological/metabolism , Adult , Emotions/physiology , Facial Recognition , Female , Gyrus Cinguli/diagnostic imaging , Hair/metabolism , Humans , Magnetic Resonance Imaging , Postpartum Period/psychology , Prefrontal Cortex/diagnostic imaging , Pregnancy , Pregnancy Complications/psychology , Pregnancy Trimester, Third/psychology , Stress, Psychological/psychology , Stroop Test , Young Adult
7.
Gene Ther ; 15(19): 1302-10, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18463688

ABSTRACT

Tumor cells evade immunosurveillance by elements of the innate immune system, such as natural killer (NK) cells, by downregulating or 'shedding' certain cell-surface molecules like mouse UL16-binding protein-like transcript 1 (MULT1) that can activate NK cells through NK cell receptors such as NKG2D; they also avoid Fas-mediated apoptosis by downregulating its expression. In the present study we report the design and evaluation of the antitumor activity of a novel fusion protein, MULT1E/FasTI, consisting of the extracellular domain of MULT1 and the transmembrane and intracellular domains of Fas. The fusion construct (pMULT1E/FasTI) was transfected into the mouse pulmonary carcinoma cell line TC-1; and stable cell clones expressing the fusion protein were established. In-vitro cell culture studies demonstrated that the binding of the NKG2D/Fc, a recombinant protein of mouse NK cell receptor, to MULT1E/FasTI expressed on tumor cells was able to elicit apoptosis as assayed by Annexin V-fluorescein isothiocyanate staining and caspase-3 enzyme-linked immunosorbent assay and to activate NKG2D-expressing cells, such as NK cells. In-vivo subcutaneous tumor studies demonstrated that tumor cells expressing MULT1E/FasTI grew significantly slower than cells without the protein. Pulmonary metastasis studies showed that most of the mice completely rejected tumor cells expressing MULT1E/FasTI. This approach may generate a new therapeutic agent for tumor treatment when combined with tumor cell-specific gene delivery vehicles such as oncolytic adenovirus vectors.


Subject(s)
Carcinoma/therapy , Carrier Proteins/genetics , Genetic Therapy/methods , Histocompatibility Antigens Class I/genetics , Killer Cells, Natural/immunology , Lung Neoplasms/therapy , fas Receptor/genetics , Animals , Apoptosis , Carcinoma/immunology , Cell Line, Tumor , Cloning, Molecular , Female , Gene Expression , Lung Neoplasms/immunology , Lymphocyte Activation , Male , Membrane Proteins , Mice , Mice, Inbred C57BL , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/therapeutic use , Transfection/methods
8.
Nucleic Acids Res ; 28(17): 3216-23, 2000 Sep 01.
Article in English | MEDLINE | ID: mdl-10954588

ABSTRACT

Helicobacter pylori is a gram-negative bacterium, which colonizes the gastric mucosa of humans and is implicated in a wide range of gastroduodenal diseases. The genomic sequences of two H.pylori strains, 26695 and J99, have been published recently. About two dozen potential restriction-modification (R-M) systems have been annotated in both genomes, which is far above the average number of R-M systems in other sequenced genomes. Here we describe a functional analysis of the 16 putative Type II R-M systems in the H. pylori J99 genome. To express potentially toxic endonuclease genes, a unique vector was constructed, which features repression and antisense transcription as dual control elements. To determine the methylation activities of putative DNA methyltransferases, we developed polyclonal antibodies able to detect DNA containing N6-methyladenine or N4-methylcytosine. We found that <30% of the potential Type II R-M systems in H.pylori J99 strain were fully functional, displaying both endonuclease and methyltransferase activities. Helicobacter pylori may maintain a variety of functional R-M systems, which are believed to be a primitive bacterial 'immune' system, by alternatively turning on/off a subset of numerous R-M systems.


Subject(s)
Adenine/analogs & derivatives , Cytosine/analogs & derivatives , DNA Modification Methylases/genetics , Deoxyribonucleases, Type II Site-Specific/genetics , Genes, Bacterial/genetics , Genome, Bacterial , Helicobacter pylori/enzymology , Helicobacter pylori/genetics , Adenine/immunology , Adenine/metabolism , Antibodies/immunology , Cloning, Molecular , Computational Biology , Cytosine/immunology , Cytosine/metabolism , DNA Methylation , DNA Modification Methylases/metabolism , Deoxyribonucleases, Type II Site-Specific/metabolism , Genetic Vectors/genetics , Open Reading Frames/genetics
9.
Gene ; 71(2): 491-9, 1988 Nov 30.
Article in English | MEDLINE | ID: mdl-3224833

ABSTRACT

Polymerase chain reaction conditions were established for the in vitro amplification of eukaryotic small subunit ribosomal (16S-like) rRNA genes. Coding regions from algae, fungi, and protozoa were amplified from nanogram quantities of genomic DNA or recombinant plasmids containing rDNA genes. Oligodeoxynucleotides that are complementary to conserved regions at the 5' and 3' termini of eukaryotic 16S-like rRNAs were used to prime DNA synthesis in repetitive cycles of denaturation, reannealing, and DNA synthesis. The fidelity of synthesis for the amplification products was evaluated by comparisons with sequences of previously reported rRNA genes or with primer extension analyses of rRNAs. Fewer than one error per 2000 positions were observed in the amplified rRNA coding region sequences. The primary structure of the 16S-like rRNA from the marine diatom, Skeletonema costatum, was inferred from the sequence of its in vitro amplified coding region.


Subject(s)
Gene Amplification , RNA, Ribosomal/genetics , Base Sequence , Cloning, Molecular , Molecular Sequence Data , Phylogeny
10.
Gene ; 156(1): 33-6, 1995 Apr 14.
Article in English | MEDLINE | ID: mdl-7737513

ABSTRACT

In this paper, we describe various parameters affecting the regulation of expression of the sCD4-183 gene, encoding the 183-amino-acid soluble human two-domain CD4 protein, from phage-T7-based pET vectors. We demonstrated that for the sCD4-183 protein, the highest protein yield was obtained using vector pET-9a, in which neither expression of the T7 RNA polymerase-encoding gene nor the target gene was tightly regulated. The highest overall protein yield was obtained from cells grown for 24 h in the absence of inducer, a strategy that may be generally useful for production of less toxic proteins. We also describe two modifications of the pET vector system that effectively minimized leaky (uninduced) expression and enhanced plasmid stability. These have potential use in the production of toxic proteins, or of non-toxic proteins produced in high-density cultures.


Subject(s)
Bacteriophage T7/genetics , CD4 Antigens/biosynthesis , Escherichia coli/genetics , Gene Expression Regulation , Genetic Vectors/genetics , CD4 Antigens/genetics , Escherichia coli/metabolism , Genetic Vectors/metabolism , Humans , Isopropyl Thiogalactoside , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics
11.
Assist Technol ; 12(2): 123-31, 2000.
Article in English | MEDLINE | ID: mdl-11508402

ABSTRACT

Electronic aids to daily living (EADLs) allow persons who have a degenerative neuromuscular condition such as Duchenne's muscular dystrophy to operate a wide variety of household and workplace appliances without assistance (independent of family members or other caregivers). There is very little published research to describe how well EADLs are perceived by users to enhance their sense of personal autonomy, functional independence, and psychological well being. Psychosocial impact is a significant determinant of how users perceive the benefit of assistive devices to their quality of life. This study compared the perceived psychosocial impact of EADLs on a group of device users with the anticipated impact of EADLs reported by a group who were eligible for, but had not yet received, these devices. The perceptions of the user group were measured at two points in time, approximately 6 to 9 months apart, to examine the stability of psychosocial impact. The Psychosocial Impact of Assistive Devices Scale was the instrument used to assess perceived impact. EADLs were found to produce similar degrees of positive impact on users and positive perceptions of anticipated impact on those without devices. The psychosocial impact on users was stable over time. The results indicate that the perceived benefits of EADLs to the autonomy, functional independence, and psychological well being of both users and nonusers are positive and strikingly similar. The study is an important first step in attempting to quantify psychosocial outcomes for EADLs in a way that might facilitate economic analysis of these devices in the future.


Subject(s)
Adaptation, Psychological , Electronics, Medical , Neurodegenerative Diseases/rehabilitation , Quality of Life , Self-Help Devices , Activities of Daily Living , Adult , Case-Control Studies , Female , Humans , Longitudinal Studies , Male , Multivariate Analysis , Neurodegenerative Diseases/psychology , Ontario
12.
Rev Sci Instrum ; 79(10): 10F511, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19044656

ABSTRACT

A consortium consisting of four EURATOM Associations has been set up to develop the project plan for the full development of the ITER bolometer diagnostic and to continue urgent R&D activities. An overview of the current status is given, including detector development, line-of-sight optimization, performance analysis as well as the design of the diagnostic components and their integration in ITER. This is complemented by the presentation of plans for future activities required to successfully implement the bolometer diagnostic, ranging from the detector development over diagnostic design and prototype testing to RH tools for calibration.

13.
J Mol Evol ; 39(1): 56-61, 1994 Jul.
Article in English | MEDLINE | ID: mdl-8064873

ABSTRACT

Southern analysis of genomic DNA identified multiple-copy actin gene families in Lagenidium giganteum and Pythium irregulare (Oomycota). Polymerase chain reaction (PCR) protocols were used to amplify members of these actin gene families. Sequence analysis of genomic coding regions demonstrated five unique actin sequences in L. giganteum (Lg-Ac1, 2, 3, 4, 5) and four unique actin sequences in P. irregulare (Pi-Ac1, 2, 3, 4); none were interrupted by introns. Maximum parsimony analysis of the coding regions demonstrated a close phylogenetic relationship between oomycetes and the chromophyte alga Costaria costata. Three types of actin coding regions were identified in the chromophyte/oomycete lineage. The type 1 actin is the single-copy coding region found in C. costata. The type 2 and type 3 actins are found in the oomycetes and are the result of a gene duplication which occurred soon after the divergence of the oomycetes from the chromophyte algae. The type 2 coding regions are the single-copy sequence of Phytophthora megasperma, the Phytophthora infestans actB gene, Lg-Ac5 and Pi-Ac2. The type 3 coding regions are the single-copy sequence of Achlya bisexualis, the P. infestans actA gene, Lg-Ac1, 2, 3, 4 and Pi-Ac1, 3, 4.


Subject(s)
Actins/genetics , Biological Evolution , Multigene Family , Phaeophyceae/genetics , Base Sequence , DNA Primers , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction/methods , Sequence Homology, Nucleic Acid
14.
Chromosoma ; 92(3): 234-41, 1985.
Article in English | MEDLINE | ID: mdl-4017747

ABSTRACT

Sedimentation studies of DNA from chromosomes extracted from human mitotic cells showed that high-molecular-weight DNA can be obtained if cell hypotonic treatments and prolonged metaphase blocks are avoided. Two types of large double-stranded DNA were observed. One of these (Mr = 2.5 X 10(8)) appeared as a size class with characteristics reminiscent of the chromosomal DNA subunit hypothesis. However, this DNA is the decay product of larger molecules, whose minimum molecular weight is 6 X 10(8).


Subject(s)
DNA, Neoplasm/isolation & purification , Antineoplastic Agents/pharmacology , Benzimidazoles/pharmacology , Cell Fractionation , Cell Line , Chromosomes, Human/ultrastructure , DNA Replication , Humans , Hydroxyurea/pharmacology , Metaphase/drug effects , Mitosis/drug effects , Molecular Weight , Nocodazole , Thymidine/metabolism , Tritium
15.
Mol Biol Evol ; 10(3): 689-703, 1993 May.
Article in English | MEDLINE | ID: mdl-7687735

ABSTRACT

Reverse transcriptase and polymerase chain reaction methods were used to amplify and clone actin cDNAs from the chlorophylls a + C-containing unicellular alga, Emiliania huxleyi (Prymnesiophyta). Actins in E. huxleyi are defined by a gene family containing at least six distinct coding regions that were derived from relatively recent gene duplications. Five of the coding regions (types 1, 2, and 4-6) varied only among synonymous codons. A nonsynonomous change in a sixth coding region (type 3 actin) produced a serine-to-phenylalanine replacement. The G + C composition of third positions in E. huxleyi actin genes is 98%, which contrasts with the mean value of 50% G + C content for first and second positions. Distance-matrix and parsimony analyses of actin genes identified the prymnesiophytes as a photosynthetic lineage that is not already related to other eukaryotic algal groups.


Subject(s)
Actins/genetics , Eukaryota/genetics , Phylogeny , Amino Acid Sequence , Base Composition , Base Sequence , Blotting, Southern , DNA , Molecular Sequence Data , Oligodeoxyribonucleotides , Phytoplankton/genetics , Polymerase Chain Reaction/methods , RNA-Directed DNA Polymerase , Restriction Mapping , Sequence Homology, Nucleic Acid
16.
J Mol Evol ; 33(6): 525-36, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1779434

ABSTRACT

Actin genic regions were isolated and characterized from the heterokont-flagellated protists, Achlya bisexualis (Oomycota) and Costaria costata (Chromophyta). Restriction enzyme and cloning experiments suggested that the genes are present in a single copy and sequence determinations revealed the existence of two introns in the C. costata actin genic region. Phylogenetic analyses of actin genic regions using distance matrix and maximum parsimony methods confirmed the close evolutionary relationship of A. bisexualis and C. costata suggested by ribosomal DNA (rDNA) sequence comparisons and reproductive cell ultrastructure. The higher fungi, green plants, and animals were seen as monophyletic groups; however, a precise order of branching for these assemblages could not be determined. Phylogentic frameworks inferred from comparisons of rRNAs were used to assess rates of evolution in actin genic regions of diverse eukaryotes. Actin genic regions had nonuniform rates of nucleotide substitution in different lineages. Comparison of rates of actin and rDNA sequence divergence indicated that actin genic regions evolve 2.0 and 5.3 times faster in higher fungi and flowering plants, respectively, than their rDNA sequences. Conversely, animal actins evolve at approximately one-fifth the rate of their rDNA sequences.


Subject(s)
Actins/genetics , Oomycetes/genetics , Phaeophyceae/genetics , Phylogeny , Amino Acid Sequence , Animals , Base Sequence , Biological Evolution , Blotting, Southern , DNA, Protozoan , Molecular Sequence Data
17.
Antimicrob Agents Chemother ; 35(1): 182-4, 1991 Jan.
Article in English | MEDLINE | ID: mdl-2014975

ABSTRACT

At clinically achievable levels (e.g., 25 micrograms/ml), sulbactam exerted no effect on aminoglycoside concentrations when incubated together in pooled serum at 37 degrees C for up to 24 h. Sulbactam alone and in combination with ampicillin or cefoperazone inactivated tobramycin, gentamicin, netilmicin, and amikacin in vitro when the sulbactam concentration was 200 to 225 micrograms/ml. At 75 micrograms/ml, sulbactam inactivated only tobramycin. Inactivation of tobramycin by high concentrations of sulbactam occurred even at -20 degrees C, but not at -70 degrees C, and was influenced by the serum matrix.


Subject(s)
Anti-Bacterial Agents/antagonists & inhibitors , Anti-Bacterial Agents/pharmacology , Sulbactam/pharmacology , Amikacin/antagonists & inhibitors , Ampicillin/pharmacology , Cefoperazone/pharmacology , Drug Interactions , Drug Therapy, Combination/pharmacology , Gentamicins/antagonists & inhibitors , Immunoenzyme Techniques , Netilmicin/antagonists & inhibitors , Piperacillin/pharmacology , Tobramycin/antagonists & inhibitors
18.
J Biol Chem ; 275(22): 17086-93, 2000 Jun 02.
Article in English | MEDLINE | ID: mdl-10748211

ABSTRACT

We have isolated a novel restriction endonuclease, Hpy188I, from Helicobacter pylori strain J188. Hpy188I recognizes the unique sequence, TCNGA, and cleaves the DNA between nucleotides N and G in its recognition sequence to generate a one-base 3' overhang. Cloning and sequence analysis of the Hpy188I modification gene in strain J188 reveal that hpy188IM has a 1299-base pair (bp) open reading frame (ORF) encoding a 432-amino acid product. The predicted protein sequence of M.Hpy188I contains conserved motifs typical of aminomethyltransferases, and Western blotting indicates that it is an N-6 adenine methyltransferase. Downstream of hpy188IM is a 513-bp ORF encoding a 170-amino acid product, that has a 41-bp overlap with hpy188IM. The predicted protein sequence from this ORF matches the amino acid sequence obtained from purified Hpy188I, indicating that it encodes the endonuclease. The Hpy188I R-M genes are not present in either strain of H. pylori that has been completely sequenced but are found in two of 11 H. pylori strains tested. The significantly lower G + C content of the Hpy188I R-M genes implies that they have been introduced relatively recently during the evolution of the H. pylori genome.


Subject(s)
Deoxyribonucleases, Type II Site-Specific/isolation & purification , Gene Transfer, Horizontal , Genome, Bacterial , Helicobacter pylori/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , DNA Primers , Deoxyribonucleases, Type II Site-Specific/genetics , Deoxyribonucleases, Type II Site-Specific/metabolism , Molecular Sequence Data , Open Reading Frames , Substrate Specificity
19.
J Eukaryot Microbiol ; 42(4): 411-5, 1995.
Article in English | MEDLINE | ID: mdl-7620466

ABSTRACT

Small subunit (16S-like) ribosomal RNA sequences were obtained from representatives of all four families constituting the order Trichomonadida. Comparative sequence analysis revealed that the Trichomonadida are a monophyletic lineage and a deep branch of the eukaryotic tree. Relative to the early divergent eukaryotic assemblages the branching pattern within the Trichomonadida is very shallow. This pattern suggests the Trichomonadida radiated recently, perhaps in conjunction with their animal hosts. From a morphological perspective the Devescovinidae and Calonymphidae are considered more derived than the Monocercomonadidae and Trichomonadidae. Molecular trees inferred by distance, parsimony and likelihood techniques consistently show the Devescovinidae and Calonymphidae are the earliest diverging lineages within the Trichomonadida, however bootstrap values do not strongly support a particular branching order. In an analysis of all known 16S-like ribosomal RNA sequences, the Trichomonadida share most recent common ancestry with unidentified protists from the hindgut of the termite Reticulitermes flavipes. The position of two putative free-living trichomonads in the tree is indicative of derivation from symbionts rather than direct descent from some free-living ancestral trichomonad.


Subject(s)
Phylogeny , RNA, Ribosomal, 16S/genetics , Trichomonadida/classification , Trichomonadida/genetics , Animals , Base Sequence , DNA Primers , Molecular Sequence Data , Trichomonas/classification , Trichomonas/genetics , Trichomonas vaginalis/classification , Trichomonas vaginalis/genetics , Tritrichomonas foetus/genetics
20.
Mol Phylogenet Evol ; 1(3): 231-41, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1342940

ABSTRACT

Nucleotide sequences of the small subunit ribosomal RNA (18S) gene were used to investigate evolutionary relationships within the Fungi. The inferred tree topologies are in general agreement with traditional classifications in the following ways: (1) the Chytridiomycota and Zygomycota appear to be basal groups within the Fungi. (2) The Ascomycota and Basidiomycota are a derived monophyletic group. (3) Relationships within the Ascomycota are concordant with traditional orders and divide the hemi- and euascomycetes into distinct lineages. (4) The Basidiomycota is divided between the holobasidiomycetes and phragmobasidiomycetes. Conflicts with traditional classification were limited to weakly supported branches of the tree. Strongly supported relationships were robust to minor changes in alignment, method of analysis, and various weighting schemes. Weighting, either of transversions or by site, did not convincingly improve the status of poorly supported portions of the tree. The rate of variation at particular sites does not appear to be independent of lineage, suggesting that covariation of sites may be an important phenomenon in these genes.


Subject(s)
Fungi/classification , Fungi/genetics , Phylogeny , RNA, Fungal/genetics , RNA, Ribosomal, 18S/genetics , Animals , Ascomycota/classification , Ascomycota/genetics , Base Sequence , Basidiomycota/classification , Basidiomycota/genetics , Eukaryotic Cells , Molecular Sequence Data , Sequence Homology, Nucleic Acid , Species Specificity
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