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PubMed1996

Drosophila immunity: a comparative analysis of the Rel proteins dorsal and Dif in the induction of the genes encoding diptericin and cecropin.

In Drosophila, bacterial challenge induces the rapid transcription of several genes encoding potent antibacterial peptides. The upstream sequences of the diptericin and cecropin Al genes, which have been investigated in detail, contain two, respectively one sequence element homologous to the binding site of the mammalian nuclear factor kappaB. These elements have been shown to be mandatory for immune-induced transcription of both genes. Functional studies have shown that these kappaB-related elements can be the target for the Drosophila Rel proteins dorsal and Dif. Here we present a comparative analysis of the transactivating capacities of these proteins on reporter genes fused to either the diptericin or the cecropin kappaB-related motifs. We conclude from our results: (i) the kappaB motifs of the diptericin and cecropin genes are not functionally equivalent; (ii) the dorsal and Dif proteins have distinct DNA-binding characteristics; (iii) dorsal and Dif can heterodimerize in vitro; (iv) mutants containing no copies of dorsal and a single copy of Dif retain their full capacity to express the diptericin and cecropin genes in response to challenge.

Animals↗
PubMed1995

From Polyplacophora to Cephalopoda: comparative analysis of nitric oxide signalling in mollusca.

The distribution of putative nitric oxide synthase (NOS)-containing cells has been analysed using NADPH-d histochemistry in the CNS and peripheral tissues in more than 2D ecologically and systematically different molluscan genera representing 3 main classes of the phylum MOLLUSCA: Polyplacophora (Lepidopleurus, Lepidozona, Katharina), Gastropoda (Littorina, Lymnaea, Aplexa, Physa, Planorbarius, Planorbis, Helisoma, Biomphalaria, Helix, Limax, Cepaea, Bulla, Aplysia, Phyllaplysia, Philine, Pleurobranchea, Tritonia, Armina, Flabellina, Cadlina) and Cephalopoda (Octopus, Sepia, Rossia, Loligo). Several species were used for more detailed immunohistochemical, biochemical, biophysical and physiological studies to further assay of NOS activity and to analyse functional roles of nitric oxide (NO) in these animals. The main conclusions of our comparative analysis and literature survey can be summarised as following: (i) There is strong evidence for the presence of NO-dependent signalling pathways in different molluscan species. (ii) We hypothesise that a general tendency in the evolution of NADPH-d-reactive cells in Mollusca is a migration of nitrergic function from periphery to the CNS. Also, different isoforms of NOS appear to be present in any one species. (iii) One of the main functional targets of NO signalling is the feeding system. However, there are obvious differences between predators (many labelled central motoneurons) and herbivorous species (many labelled peripheral putative sensory cells) as well as between land/freshwater and marine animals. Nevertheless, in all species tested NO-activated feeding-like motor patterns in the buccal ganglia. Additional functional and cellular targets for NO in molluscs are also considered. We briefly review neuromodulatory mechanisms of NO action and we consider molluscs as useful model systems for investigations of the roles of NO.

Animals↗
PubMed1986

[Use of the indirect immunofluorescence method for the comparative analysis of histones].

With the help of indirect immunofluorescence on the model systems--a ploid line of wheat, haploid and diploid cells of Chlamydomonas reinhardii, glass beads with adsorbed histones--a study was made of the dependence of ultimate dilutions (UD) of antihistone sera on the quantity, density and immunochemical properties of histones--antigens. The UD value in the artificial model system (glass beads) increased with the rise in the quantity and density of histones on bead to some definite limits, and then the UD remains constant to be determined only by the titre of antiserum. In natural model system (wheat, Chlamydomonas reinhardii), with the rise in quantities of DNA and histones in the nucleus their densities remain constant, with no changes of UD values being observed. The results obtained are discussed in terms of establishing the dependence of UD on immunochemical properties of histones-antigens. Thus, the method of indirect immunofluorescence may be used for comparative analysis of immunochemical properties of histones in various objects.

Adsorption↗
PubMed1995

Comparative analysis of ATPase of yeast elongation factor 3 and ATPase associated with Tetrahymena ribosomes.

Elongation factor 3 (EF-3) is a unique and essential requirement of the fungal translational apparatus. The biochemical function of EF-3 has recently been defined. The protein removes deacylated tRNA from the ribosomal exit site (E-site) thus facilitating occupation of the ribosomal A-site by aa-tRNA. A functional homolog of yeast EF-3 has not been identified in non-fungal species. Yeast EF-3 is a ribosome-dependent ATPase that can also accept GTP and ITP as substrates. The function of EF-3 in ribosomal reactions requires ATP hydrolysis. An ATPase activity associated with higher eukaryotic ribosomes has been claimed to be a direct functional homolog of yeast EF-3. Comparative analysis of biochemical, immunological and functional properties of ATPase activity associated with the ribosomes isolated from the ciliated protozoan Tetrahymena pyriformis with that of yeast EF-3 ATPase indicates that these two activities are significantly different. Results reported in this communication strongly suggest that the ribosome associated ATP hydrolytic activity of Tetrahymena pyriformis is not a functional homolog of yeast EF-3.

Adenosine Triphosphatases↗
PubMed1993

Comparative analysis of beta-adrenergic receptor kinase and beta-arrestin mRNA expression in human cells.

Receptor phosphorylation is a key step in the process of rapid desensitization. beta-Adrenergic receptor kinase is a specific receptor kinase that is known to phosphorylate and induce desensitization of several G-coupled synaptic receptors only when they are occupied by their agonists. We recently cloned human beta ARK cDNA and reported high levels of beta ARK expression in human peripheral blood leukocytes, also providing the first evidence for its possible functional role in these cells. Complete homologous receptor desensitization by beta ARK requires an additional cytosolic factor, called beta-arrestin. In the present study, we have cloned a 212 bp fragment of the human beta-arrestin cDNA to perform a comparative analysis of beta ARK and beta-arrestin mRNA expression in various human cell types. We found that also beta-arrestin mRNA is abundant in non-innervated tissues and cells. The fact that the entire machinery for G-coupled receptor desensitization is highly expressed in these cells further supports the idea that beta ARK may regulate nonsynaptic as well as synaptic receptors.

Antigens↗
PubMed1990

Comparative analysis of collagens solubilized from human foetal, and normal and osteoarthritic adult articular cartilage, with emphasis on type VI collagen.

The different collagen types were extracted sequentially, by 4 M guanidinium chloride and pepsin, from human foetal and normal and osteoarthritic adult articular cartilage. They were characterized by electrophoresis and immunoblotting. Most of the collagenous proteins present in articular cartilage from young human foetuses were solubilized: almost 40% of the total collagen was extracted in the native form with 4 M guanidinium chloride. Type VI collagen was detected in this fraction as high-molecular-mass chains (185-220 kDa) and a low-molecular-mass chain (140 kDa). Type II, IX and XI collagens were also present, but were extracted more extensively by pepsin digestion. Comparative analysis of normal and osteoarthritic cartilage from adults reveals some major differences: an increase in the solubility of the collagen and modifications of soluble collagen types in osteoarthritic cartilage. Furthermore, type VI collagen was present at a higher concentration in guanidinium chloride extracts of osteoarthritic cartilage than those of normal tissue. This finding was corroborated by electron microscopic observations of the same samples: abundant (100 nm) periodic fibrils were observed in the disorganized pericellular capsule of cloned cells in osteoarthritic cartilage. In normal tissues the pericellular zone was more compact and contained only a few such banded fibrils. The differences in the collagen types solubilized from normal and osteoarthritic cartilage, although corresponding to a minor proportion of the total collagen, demonstrate that important modifications in chondrocyte metabolism and in the collagenous network do occur in degenerated cartilage.

Aged↗
PubMed1993

Antifungal triazole alcohols: a comparative analysis of structure-activity, structure-teratogenicity and structure-therapeutic index relationships using the Multiple Computer-Automated Structure Evaluation (Multi-CASE) methodology.

An increase in the opportunistic fungal infections necessitates a design of new more effective and safer antifungal agents. Triazole alcohols are effective antifungals, but have a risk of teratogenicity associated with them. Therefore, successful design of drugs from this class depends on understanding the structure-activity and structure-teratogenicity relationships in conjunction. To this end, we applied the Multiple Computer-Automated Structure Evaluation (Multi-CASE) methodology to a study of the relationships between the structures of 71 triazole alcohols and their in vitro antifungal activity, teratogenicity, and therapeutic index. For each end point, several relevant structural descriptors were identified. A comparative analysis of the Multi-CASE results indicates that cyano, methoxy groups, and ortho-difluorination on the aromatic ring decrease antifungal activity, but not the therapeutic index because of the concomitant negative contribution to teratogenicity. Metabolically deactivating para-substitution in the benzene ring is beneficial for the therapeutic index in agreement with the idea of metabolically induced teratogenicity. Fluorinated para-alkyl substituents are most preferable. The pattern of ortho-substitution in the benzene ring affects both antifungal and teratogenic activity. This suggests that the relative orientation of the benzene ring with respect to the rest of the molecule may play a modulating role. The Multi-CASE model could correctly predict, a priori, the teratogenicity and antifungal potency of SCH 39304 and ICI 156,066 and be used to optimize the structure and therapeutic index of the latter.

Animals↗
PubMed1994

[Comparative analysis of sutures and stapling for colorectal anastomosis in resection of the rectum in carcinoma].

In Clinic for general and vascular surgery - Military Medical Academy Belgrade since 1987 to 1993 in treatment of the rectal cancer it was done 326 low anterior resections. In 149 patients anastomosis was done with sutures and in 177 with stapler. Half of them were more then 60 years old, and in 40% of patients carcinoma was staged as Dukes C or D. In group I tumor was localised in the middle or distal third of rectum in 24.8% of patients while in group II this was in 75.7%. Anastomosis related complications where rare in stapler group, clinically evident anastomotic dehiscence was found in 11.4% patients in I group and in 99% in II group. Total mortality was 3.1%; 3.4% in the I group and 2.8% in the II group. In our comparative analysis of early complications after low anterior resection of rectum when colorectal anastomosis was done with suture or stapler technic we have found that stapler technic give opportunity for creating much more low colorectal anastomoses which are safe and with less complications and with the same oncologic control of disease.

Adult↗
PubMed1993

Serositis: comparative analysis of histological findings and pathogenetic mechanisms in nonbacterial serosal inflammation.

Peritonitis is the established term for infective inflammation of the peritoneum, while serositis generally refers to nonorganismal inflammation in any serous cavity, including the peritoneum. In continuous ambulatory peritoneal dialysis (CAPD) literature, however, culture-negative peritoneal inflammation is referred to as "sterile" or "chemical" peritonitis. These terms not only imply unwarranted etiologic assumptions, but may also deflect attention from the existence of medical conditions to which the peritoneum is subject. This is evident in CAPD literature where there is little recognition that the peritoneum, as a member of the serosa and a secretor of lamellar bodies, is prey to a wide range of disorders. Thus before, during, and after CAPD, the membrane is liable to fall victim to disease states unconnected with the process of dialysis. Significant peritoneal pathology occurs as part of a pan-serositis, which may be metabolic (uremia, cholesterolosis), autoimmune (systemic lupus erythematosus, rheumatoid disease, acute rheumatism, endocrinopathies), genetic (recurrent hereditary polyserositis), allergic (eosinophilic serositis), and granulomatous in nature. This paper presents a comparative analysis of histopathological presentation and pathogenetic mechanisms involved in all forms of peritoneal serositis. It incorporates recent advances in molecular biology of the membrane into a holistic reappraisal of peritoneal pathology, revealing hitherto unrecognized homologies in peritoneal reaction to diverse disorders.

Animals↗
PubMed1988

Comparative analysis of the transcripts mapped in the BamHI DNA fragment B of avirulent HSV-1 HFEM, virulent HSV-1 F, and their intratypic recombinant viruses.

HSV-1 HFEM, whose genome harbors a deletion of 4.1 kbp (0.762 to 0.789 map units (mu] is avirulent for mice and tree shrews by the intraperitoneal (i.p.) application route. Insertion of the BamHI DNA fragment B (0.738 to 0.809 mu) and/or the MluI DNA fragment (0.7615 to 0.796 mu) molecularly cloned from virulent HSV-1 F, restored the i.p. pathogenicity to strain HFEM and led to the isolation of virulent intratypic recombinants. In order to determine the RNA transcripts mapped in the BamHI DNA fragment B of the HSV-1 HFEM, HSV-1 F, and their intratypic recombinants R15, R19, R26, and R-Ml-C1, a comparative analysis was performed using Northern blot hybridizations. Two novel RNA transcripts of 3.5 and 1.5 kb were detected which hybridize to the left terminus (0.738 to 0.746 mu) of the BamHI DNA fragment B. The 1.5 kb RNA transcript was missing in the avirulent HSV-1 HFEM. Hybridization with the BssHII DNA fragment F (0.760 to 0.762 mu) led to detection of a 3.5 kb RNA transcript by HSV-1 HFEM which was missing in all other viruses tested. In contrast a 1.5 kb RNA transcript was detectable in all other virus strains with the exception of HSV-1 HFEM. The 3.5 kb transcript hybridized to the right-hand flank of the deleted region in the genome of HSV-1 HFEM (Asp718/SalI DNA fragment; 0.786 to 0.79 mu). The detection of the novel 1.5 kb RNA, which is missing in HSV-1 HFEM, and the appearance of the newly transcribed 3.5 kb RNA in HSV-1 HFEM only, indicates a new open reading frame in this particular region as a consequence of the fusion of the DNA sequences at both ends of the deletion in the genome of HSV-1 HFEM.

Chromosome Deletion↗
PubMedDate not supplied

[Comparative analysis of sutured and stapled colorectal anastomoses].

In the period of 1987-1993 at the Clinic of General and Vascular Surgery, Military Medical Academy, 364 colorectal anastomoses were performed; the group I was composed of 167 patients with sutured anastomoses, and 197 patients with stapled anastomoses were in the group II. More than half of patients were over 60, and ratio between males and females was 2:1. The reason for resection in almost 90% of the patients was adenocarcinoma of the rectum of which in 40% of the patients the process advanced up to stages C and D by Dukes. Pathologic process in the group I was localized in the lower two thirds of the rectum in 24.6% of the patients, while the percentage in the group II was tripled--76.1%. Surgical wound complications were most frequent in both groups (14.3%:9.6%), and complications associated with anastomosis were less frequent in the stapler group. Clinically clear anastomosis dehiscence appeared in 11.4% of the group I and in 10.7% of the group II. Total mortality was 3.3% (Group I 3.6%, group II 3.0%). By comparative analysis of early complications after resection of the rectum with sutured or stapled colorectal anastomosis, it is concluded that the introduction of staplers in colorectal surgery facilitated the easier accomplishment of larger number of low-lying colorectal or coloanal anastomoses, which are safer and followed by fewer complications, and with equal oncological disease control.

Adult↗
PubMed1992

Comparative analysis of the beta transducin family with identification of several new members including PWP1, a nonessential gene of Saccharomyces cerevisiae that is divergently transcribed from NMT1.

While investigating the expression of the Saccharomyces cerevisiae myristoyl-CoA:protein N-myristoyltransferase gene (NMT: E.C. 2.3.1.97) by Northern blot analysis, we observed another RNA transcript whose expression resembled that of NMT1 during meiosis and was derived from a gene located less than 1 kb immediately upstream of NMT1. This new gene, designated PWP1 (for periodic tryptophan protein), is divergently transcribed from NMT1 and encodes a 576-residue protein. Null mutants of PWP1 are viable, but their growth is severely retarded and steady-state levels of several cellular proteins (including at least two proteins that label with exogenous [3H]myristic acid) are drastically reduced. New methods for database searching and assessing the statistical significance of sequence similarities identify PWP1 as a member of the beta-transducin protein superfamily. Two other previously unrecognized beta-transducin-like proteins (S. cerevisiae MAK11 and D. discoideum AAC3) were also identified, and an unexpectedly high degree of sequence homology was found between a Chlamydomonas beta-like polypeptide and the C12.3 gene of chickens. A systematic and quantitative comparative analysis resulted in classifying all beta-transducin-like sequences into 11 nonorthologous families. Based on specific sequence attributes, however, not all beta-transducin-like sequences are expected to be functionally similar, and quantitative criteria for inferring functional analogies are discussed. Possible roles of repetitive tryptophan residues in proteins are also considered.

Acyltransferases↗
PubMed1988

Structural characterization of the rat carboxypeptidase A1 and B genes. Comparative analysis of the rat carboxypeptidase gene family.

Nucleotide sequencing of a rat carboxypeptidase B (CPB) cDNA and direct sequencing of the CPB mRNA via primer extension on pancreatic polyadenylated RNA has yielded the complete amino acid sequence of rat CPB. The rat enzyme is synthesized as a precursor species containing a large amino-terminal fragment (108 amino acids) that contributes a putative signal sequence and an activation peptide. The mature form of rat CPB is homologous to bovine CPB (77% identity); the amino acids in bovine CPB which have been previously implicated in catalysis or ligand binding are invariant in the rat orthologue. The rat CPB cDNA was used as a probe for the isolation of the rat CPB gene. Detailed characterization of three overlapping rat genomic clones demonstrated that the coding region for the rat CPB precursor is sequestered in 11 exons which are dispersed throughout 34 kilobase pairs of genomic DNA. The nucleotide sequence of a large part of the gene has been determined including that of the exons, the exon/intron boundaries, and the 5' flanking region. We also report the partial nucleotide sequence of the rat CPA1 gene. Comparative analysis of the structural organization of the rat CPB, rat CPA1, and rat CPA2 genes (Gardell, S. J., Craik, C. S., Clauser, E., Goldsmith, E. J., Stewart, C.-B., Graf, M., and Rutter, W. J. (1988) J. Biol. Chem. 263, 17828-17836) reveals that, with one exception, the number, position, and sequence composition of the exons in these three carboxypeptidase genes are conserved in spite of considerable divergence with respect to the lengths of their corresponding intervening sequences. Conserved sequences in the 5' flanking regions of the rat CPA1, CPA2, CPB, and other pancreas-specific genes have been identified.

Amino Acid Sequence↗
PubMed1993

Noninvasive cardiac output measurement by arterial pulse analysis compared with inert gas rebreathing.

Noninvasive cardiac output (CO) measured by arterial pulse analysis was compared with that measured by inert gas rebreathing in six healthy male volunteers. Pulse contour analysis was applied to the pressure wave output of a Finapres, which noninvasively measures continuous arterial pressure in a finger. Data were collected before, during, and after a 10-day 6 degrees head-down tilt experiment. Intravenous saline loading and lower body negative pressure stimuli varied CO over 2.8-9.6 l/min, as measured by the rebreathing technique. Because pulse contour provides only relative changes in CO, to obtain absolute values it must be calibrated against another measurement. Pulse contour data were calibrated every measurement day against the mean of two to four control rebreathing CO measurements before the lower body negative pressure or intravenous saline loading stimuli. Using one averaged calibration factor per subject for a total of 27 days, we compared the results of both methods. The linear regression between pulse contour (Pc CO) and rebreathing CO (Rebr CO) was Pc CO = 0.15 + 0.98(Rebr CO) (r = 0.96). The standard deviation of the difference of the two methods was 0.5 l/min (n = 205), excluding data used for calibration. By monitoring pulse contour CO before and during rebreathing, the rebreathing maneuver itself was shown to produce a substantial increase in CO that was mainly related to an increase in heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Cloning and sequencing of the nitrate transport system from the thermophilic, filamentous cyanobacterium Phormidium laminosum: comparative analysis with the homologous system from Synechococcus sp. PCC 7942.

A genomic region from the filamentous, thermophilic non-N2-fixing cyanobacterium Phormidium laminosum was cloned and sequenced. It includes the nitrite reductase gene (nirA) and three other genes (nrtA, B and C) located downstream of nirA, which are related to the nitrate transport system on the basis of a comparison with the homologous system from Synechococcus sp. PCC 7942. No additional nitrate assimilation-related genes were identified in about 5 kb sequenced downstream of nrtC. All four genes are arranged as an operon with a promoter-like region upstream of the nirA gene. Transcripts of these nitrate assimilation genes accumulated after long periods of nitrogen starvation. This operon also contains inverted repeat sequences in the intercistronic regions which might be involved in mRNA processing or stability.

Adenosine Triphosphate↗
PubMed1993

Comparative analysis of the methylation status of the 5' flanking region of Ha-ras in B6C3F1, C3H/He and C57BL/6 mouse liver.

We examined the methylation status of the 5' flanking region of Ha-ras in the liver of the liver tumor-prone B6C3F1 male (C57BL/6 female x C3H/He male) and C3H/He male, plus the relatively resistant C57BL/6 male mouse strains. Southern analysis revealed the presence of CCGG sites methylated at the internal cytosine, as well as unmethylated CCGG sites in all three strains. Digestion with StyI and XhoI revealed an unmethylated XhoI site in the C57BL/6 male. This pattern is not obvious in the B6C3F1 or C3H/He, indicating sequence variation and/or less methylation of Ha-ras in those strains of mice that exhibit a high propensity towards development of liver tumors.

5-Methylcytosine↗
PubMed1987

[A new basic drug prospidin in the treatment of rheumatoid arthritis. III. Comparative analysis of prospidin and cyclophosphamide].

A comparative study of the cytostatic drugs prospidin and cyclophosphamide used in equal doses for rheumatoid arthritis (RA) is reported. Clinical and immunologic effects were determined, and the nature and incidence of side effects and complications were compared. Prospidin showed a more pronounced antirheumatic effect, making for a smaller daily requirement of nonsteroid anti-inflammatory agents or hormones in hormone-dependent cases. Unlike cyclophosphamide, prospidin was not associated with severe side effects and complications precluding further use of the drug. Both drugs demonstrated a regulatory effect on RA-associated immunologic disorders.

Arthritis, Rheumatoid↗