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PubMed1983

Effect of histamine on leukocyte migration tests in vertebrates. II. Study of the lack of species specificity of leukocyte inhibiting factor--production inhibitor (LIF-PI).

Immune regulatory effects of histamine are now well established. We have previously demonstrated that human T lymphocytes having histamine receptors, produce a soluble factor inhibiting the production of LIF. In this present paper we have shown that production and function of this factor is not species specific. Indeed the leukocyte inhibiting factor-production inhibitor (LIF-PI) produced by human, guinea pig or dog lymphocytes inhibits the production of LIF by human, guinea pig and murine lymphocytes to a similar extent. This property allows for easier testing of LIF-PI particularly from human subjects.

Animals↗
PubMedDate not supplied

Species-specific reaction of liver ultrastructure in Zebrafish (Brachydanio rerio) and trout (Salmo gairdneri) after prolonged exposure to 4-chloroaniline.

The morphological alterations of hepatocytes of female zebrafish, Brachydanio rerio, and fingerling rainbow trout, Salmo gairdneri, following prolonged exposure to 0.04, 0.2 and 1 mg/L of 4-chloroaniline were investigated by means of light and electron microscopy. Changes in peroxisomes were visualized by cytochemical demonstration of catalase activity after incubation in the alkaline diaminobenzidine medium. The amount of storage products was illustrated by the silver impregnation technique. In a dose-dependent manner, the reaction of female zebrafish liver is characterized by a disturbance of hepatocytic compartmentation, progressive fenestration and fractionation of the rough endoplasmic reticulum (RER), a decrease in the number of peroxisomes and catalase activity, stratified inclusions in mitochondria, and an augmentation of lysosomes and myelinated bodies. Trout hepatocytes display nuclear inclusions, fractionation and vesiculation of the RER, and an increase in mitochondria, but a decrease of peroxisomes and catalase activity. Whereas glycogen stores are exhausted at 1 mg/L 4-chloroaniline, lipid deposits are amplified. An elevated rate of hepatocytic mitosis as well as the occurrence of glycogen-condensing cells probably derived from hepatocytes indicate the induction of proliferative processes in trout liver. Evaluation and comparison of results with earlier reports suggest that despite the unspecificity of some alterations the combination of pathological symptoms yields a syndrome specific of the species and the substance studied. As a consequence, histological and cytological investigations are recommended as a routine supplement in an integrated test schedule for the assessment of sublethal effects of pollutants in the aquatic environment.

Aniline Compounds↗
PubMed2000

Design and evaluation of a Lactobacillus manihotivorans species-specific rRNA-targeted hybridization probe and its application to the study of sour cassava fermentation.

Based on 16S rRNA sequence comparison, we have designed a 20-mer oligonucleotide that targets a region specific to the species Lactobacillus manihotivorans recently isolated from sour cassava fermentation. The probe recognized the rRNA obtained from all the L. manihotivorans strains tested but did not recognize 56 strains of microorganisms from culture collections or directly isolated from sour cassava, including 29 species of lactic acid bacteria. This probe was then successfully used in quantitative RNA blots and demonstrated the importance of L. manihotivorans in the fermentation of sour cassava starch, which could represent up to 20% of total lactic acid bacteria.

Base Sequence↗
PubMed1987

Species specificity of anti-acetylcholine receptor antibodies elicited by synthetic peptides.

Two peptides corresponding to amino acid residues 351-368 of the alpha-subunits of Torpedo and human acetylcholine receptor (AChR) were synthesized. These peptides contain a segment (residues 355-364) which displays the greatest variability in amino acid sequence between the two species. Antibodies elicited against the two peptides cross-reacted with the respective native AChRs and were shown to be species specific by radioimmunoassay, immunoblotting, and immunofluorescence microscopy. Thus, antibodies against the Torpedo peptide cross-reacted with Torpedo AChR but did not bind to mammalian or chicken AChR. Antibodies against the human peptide proved to be specific probes for mammalian muscle AChR. They cross-reacted with mammalian AChR (human, calf, mouse, and rat) but not with Torpedo or chicken AChR. These antibodies were also shown to react preferentially with the extrajunctional form of muscle AChR, as compared to their reactivity with junctional muscle AChR. In immunofluorescence experiments, the anti-human peptide antibody stained AChR aggregates in sectioned or ethanol-permeabilized rat and mouse myotubes grown in culture but did not stain living myotubes. This indicates that the sequence 351-368 of the alpha-subunit of mammalian AChR is on the cytoplasmic face of muscle cell membranes, as predicted theoretically.

Animals↗
PubMed1990

A rapid DNA assay for the species-specific detection and quantification of Brugia in blood samples.

This report describes a new assay for detecting filarial parasites of the genus Brugia in blood samples using labeled DNA probes. The sequences of these DNA probes are based on the HhaI repeat DNA family found in the genus Brugia. These DNA probes are species-specific and can detect the DNA from a single microfilaria in hybridization assays. To adapt this test for use on blood samples collected in the field, complex steps to separate microfilariae from blood cells and to purify parasite DNA were eliminated. We found that the most effective method was to filter blood samples through 5.0 microns pore nitrocellulose membranes, lyse the microfilariae on the membranes by proteinase K digestion, denature the parasite DNA with sodium hydroxide, and hybridize with the DNA probe. With this method, individual microfilariae can be visualized and counted on autoradiograms. The assay was evaluated in a mock field study using Brugia malayi-infected jirds and was found to be an efficient and accurate method for quantifying microfilariae in blood samples.

Animals↗
PubMed1999

Development of a species-specific PCR-restriction fragment length polymorphism analysis procedure for identification of Madurella mycetomatis.

Madurella mycetomatis is the commonest cause of eumycetoma in Sudan and other countries in tropical Africa. Currently, the early diagnosis of mycetoma is difficult. In attempting to improve the identification of M. mycetomatis and, consequently, the diagnosis of mycetoma, we have developed specific oligonucleotide primers based on the sequence of the internal transcribed spacer (ITS) regions spacing the genes encoding the fungal ribosomal RNAs. The ITS regions were amplified with universal primers and sequenced, and then two sets of species-specific primers were designed which specifically amplify parts of the ITS and the 5.8S ribosomal DNA gene. The new primers were tested for specificity with DNA isolated from human mycetoma lesions and DNA extracted from cultures of M. mycetomatis reference strains and related fungi as well as human DNA. To study the genetic variability of the ITS regions of M. mycetomatis, ITS amplicons were obtained from 25 different clinical isolates and subjected to restriction fragment length polymorphism (RFLP) analysis with CfoI, HaeIII, MspI, Sau3AI, RsaI, and SpeI restriction enzymes. RFLP analysis of the ITS region did not reveal even a single difference, indicating the homogeneity of the isolates analyzed during the current study.

Humans↗
PubMed1990

Species-specific oligodeoxynucleotide probes for the identification of periodontal bacteria.

Oligodeoxynucleotide probes were developed for identification of the periodontal bacteria Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, B. intermedius types I and II, B. forsythus, Eikenella corrodens, Fusobacterium nucleatum, Haemophilus aphrophilus, Streptococcus intermedius, and Wolinella recta. Probes were designed by sequencing the 16S rRNA for each bacterium, identifying hypervariable regions, and chemically synthesizing species-specific probes. These probes were specific when tested against a panel of nucleic acids from closely related bacteria.

Bacteria↗
PubMed2006

Arginine-dependent gene regulation via the ArgR repressor is species specific in chlamydia.

Some, but not all, Chlamydia spp. are predicted to encode a homolog of ArgR, a master regulatory molecule that modulates arginine biosynthesis and catabolism in bacteria in response to intracellular arginine levels. While genes for arginine biosynthesis are apparently missing in Chlamydia, a putative arginine transport system encoded by glnP, glnQ, and artJ is present. We found that recombinant Chlamydia pneumoniae ArgR functions as an arginine-dependent aporepressor that bound specifically to operator sequences upstream of the glnPQ operon. ArgR was able to repress transcription in a promoter-specific manner that was dependent on the concentration of the corepressor l-arginine. We were able to locate ArgR operators upstream of glnPQ in C. pneumoniae and Chlamydophila caviae but not Chlamydia trachomatis, which corresponded to the predicted presence or absence of ArgR in these chlamydial species. Our findings indicate that only some members of the family Chlamydiaceae have an arginine-responsive mechanism of gene regulation that is predicted to control arginine uptake from the host cell. This is the first study to directly demonstrate a species-specific mechanism of transcriptional regulation in Chlamydia.

Arginine↗
PubMed1993

Isolation of rat cDNA clones coding for the autoantigen SS-B/La: detection of species-specific variations.

Clones of cDNA coding for the autoantigen La (or SS-B) were isolated from a library made from rat liver. A comparison of the rat La cDNA (encoding from nt 38 to 1281 for rat La protein) with the sequences known for human and bovine La protein resulted in the identification of species-specific inserts. The inserts seem to be the result of multiplication of flanking sequences during evolution. In addition to these variations, we observed that rat La cDNAs exhibit non-canonical polyadenylation sites. Finally, a databank search resulted in the identification of a DNA sequence originally termed as TAG or TSG20X (GenBank accession No. X61893) which represents the C terminus of mouse La/SS-B protein.

Amino Acid Sequence↗
PubMed1988

Species specificity in the responsiveness of chick embryo neural tube explants to target-conditioned medium.

Explants from the metencephalic region of 40-h chick embryo neural tubes containing the trigeminal (V) motor nucleus were cultured in appropriate target muscle-conditioned media (MCM) derived from chick, quail and rat embryos. Enhanced neuritic outgrowth was found only in the presence of chick MCM, indicating that this early, initial responsiveness to target-released materials within this system is species-specific.

Animals↗
PubMed1996

Molecular characterization of two species-specific tandemly repeated DNAs from entomopathogenic nematodes Steinernema and Heterorhabditis (Nematoda:Rhabditida).

Two AluI tandemly repeated DNAs were cloned from two entomopathogenic nematodes: the first one from Steinernema glaseri and the second one from Heterorhabditis bacteriophora. The monomeric units of these two satellite DNAs have a repeat length of 174 and 168 bp, respectively. These AluI repeated element families appear to constitute 5.5% of the S. glaseri genome and 5% of the H. bacteriophora genome. Their A + T contents were estimated at 55% and 57%. Moreover, the monomers of these two families are quite homogeneous in sequence, showing, on average, 3.9% and 2.7% divergence from their respective consensus sequence. These results suggest that some mechanism is acting to maintain the homogeneity of these repeated DNAs despite their abundance. We have also shown that these two DNA families are species-specific and therefore could be used for the identification of Steinernema and Heterorhabditis entomopathogenic nematode species.

Animals↗
PubMed1987

Factitious hyperinsulinemic hypoglycemia: confirmation of the diagnosis by a species-specific insulin radioimmunoassay.

Surreptitious self-administration of insulin is an important cause of hypoglycemia. A 28-year-old female hospital ward clerk presented with hypoglycemia associated with an elevated plasma insulin level and a low plasma C-peptide concentration. Factitious illness was denied by the patient until it was definitively proven by using a species-specific insulin radioimmunoassay that the type of insulin circulating at the time of hypoglycemia was of animal rather than of human origin. The differential diagnosis of hypoglycemia associated with hyperinsulinemia and the current laboratory methods which may be employed to distinguish between factitious hypoglycemia and endogenous hyperinsulinism are discussed.

Adult↗
PubMed2003

Polychlorinated dibenzofurans/dibenzo-p-dioxins (PCDF/PCDDs) and other dioxin-like substances in marine organisms from the Grenland fjords, S. Norway, 1975-2001: present contamination levels, trends and species specific accumulation of PCDF/PCDD congeners.

Discharge of WHO toxicity equivalents (TEQs) of PCDF/PCDDs to Frierfjorden, Norway has been reduced from an estimated sum of 50-100 kg in the period 1951-1975 to about 6-7 kg in 1976-1990, and further to about 20 g for 1991-2000. In accordance with this, the yearly monitoring since 1987 has shown considerably decreasing contamination in organisms, first highly significant in all indicator species from 1990 to 1991, then levelling off. Present concentrations thus are still high. Compared with estimated "high background" (reference) concentrations of 10 ng TEQ(PCDF/PCDD)/kg w.w. in liver of cod and in hepatopancreas ("brown meat") of crabs, Frierfjord samples in 2001 were about 60 and 70 times higher, respectively. With considerable uncertainty due to large fluctuations, the rate of yearly decrease for TEQ(PCDF/PCDD) in cod liver 1991-2001 has been calculated to 10-12%. A hypothetic target value of 50 ng TEQ/kg w.w. will not be reached until 2015-2020, possibly even later. Including contributions from dioxin-like PCBs and PCNs, the weekly maximum tolerable amount of cod liver and crab hepatopancreas from Frierfjorden in 2001 were about 2-3 g. Multivariate analysis of PCDF/PCDD congener profiles in four fish species, mussels and crabs resulted in five distinct groups, separating four of the species and grouping the remaining two together, hence demonstrating examples of species specific accumulation characteristics.

Animals↗
PubMed2000

Species-specific difference in distribution of voltage-gated L-type Ca(2+) channels of cardiac myocytes.

Ca(2+) influx via sarcolemmal voltage-dependent Ca(2+) channels (L-type Ca(2+) channels) is the fundamental step in excitation-contraction (E-C) coupling in cardiac myocytes. Physiological and pharmacological studies reveal species-specific differences in E-C coupling resulting from a difference in the contribution of Ca(2+) influx and intracellular Ca(2+) release to activation of contraction. We investigated the distribution of L-type Ca(2+) channels in isolated cardiac myocytes from rabbit and rat ventricle by correlative immunoconfocal and immunogold electron microscopy. Immunofluorescence labeling revealed discrete spots in the surface plasma membrane and transverse (T) tubules in rabbit myocytes. In rat myocytes, labeling appeared more intense in T tubules than in the surface sarcolemma. Immunogold electron microscopy extended these findings, showing that the number of gold particles in the surface plasma membrane was significantly higher in rabbit than rat myocytes. In rabbit myocyte plasma membrane, the gold particles were distributed as clusters in both regions that were associated with junctional sarcoplasmic reticulum and those that were not. The findings are consistent with the idea that influx of Ca(2+) via surface sarcolemmal Ca(2+) channels contributes to intracellular Ca(2+) to a greater degree in rabbit than in rat myocytes.

Animals↗
PubMed1994

[Species-specific monoclonal antibodies against Chlamydia pneumoniae].

The purified elementary bodies (EBs) of C. pneumoniae ATCC VR1310 were used for primary immunization of male BALB/c mice (8 weeks of age), with the boost following on day 14. Spleen cells were fused with murine myeloma NS-1 cells on day 24 and hybrid cells were cloned by limiting dilution. Two clones, P17C2 & P33C, secreting species-specific monoclonal antibodies (MAbs) and immunoglobulin IgG2a class were obtained after elimination of those clones that produced antibodies against C. trachomatis L1, L2, A, B, C, E serovars, C. psittaci EAE strain and uninfected BGMK cell antigens. It was showed that the two clones of MAbs reacted with the MOMP 39.5 x 10(3) Da major outer membrane protein of all chlamydia species in Western blot and their ascites titers were more than 1:25 600 in Micro-IF test.

Animals↗
PubMed1997

Species-specific alternative splicing generates a catalytically inactive form of human hormone-sensitive lipase.

Hormone-sensitive lipase (HSL) catalyses the rate-limiting step of adipose tissue lipolysis. The enzyme is also expressed in steroidogenic tissues, mammary gland, muscle tissues and macrophages. A novel HSL mRNA termed hHSL-S, 228 bp shorter than the full-length HSL mRNA, was detected in human adipocytes. hHSL-S mRNA results from the in-frame skipping of exon 6, which encodes the serine residue of the catalytic triad. The corresponding 80 kDa protein was identified in human adipocytes after immunoprecipitation. The truncated protein expressed in COS cells showed neither lipase nor esterase activity but was phosphorylated by cAMP-dependent protein kinase. hHSL-S mRNA was found in all human tissues expressing HSL, except brown adipose tissue from newborns. It represented approx. 20% of total HSL transcripts in human subcutaneous adipocytes. No alternative splicing was detected in other mammals. Human and mouse three-exon HSL minigenes transfected into primate and rodent cell lines reproduced the splicing pattern of the endogenous HSL genes. Analysis of hybrid human/mouse minigenes transfected into human cell lines showed that cis-acting elements responsible for the skipping of human exon 6 were restricted to a 247 bp region including exon 6 and the first 19 nt of intron 6. Moreover, divergence in exonic splicing elements between mouse and human was shown to be critical for the species-specific alternative splicing.

Alternative Splicing↗
PubMed1990

Switches in species-specific codon preferences: the influence of mutation biases.

A model of synonymous codon usage is developed in which the most frequent codons are selectively advantageous because of their coadaptation with tRNA abundances. Random drift opposes the progress of this coevolution by pushing codon frequencies in the direction of the frequency that would result from mutation in the absence of selection. It is predicted that, within a certain range, an increased mutation bias away from an advantageous codon has little influence on its usage in highly expressed genes. However, a subsequent small increase in mutation bias over a critical range leads to a large reduction in the frequency of the codon. The switch in preference from one synonym to another is a sharp transition, with no stable intermediate state in which neither codon is advantageous. Codon usage patterns were compared among three related bacterial species of differing genomic G & C contents, Escherichia coli, Serratia marcescens, and Proteus vulgaris. It was found that although changes in mutation biases do not always result in switches in codon preferences, some switches have occurred in the direction of species-specific mutation biases. Fluctuating mutation biases may therefore be the main cause of differences between species in their codon preferences.

Amino Acids↗
PubMed2004

Retrovirus resistance factors Ref1 and Lv1 are species-specific variants of TRIM5alpha.

Mammalian cells express several factors that act in a cell-autonomous manner to inhibit retrovirus replication. Among these are the Friend virus susceptibility factor 1/lentivirus susceptibility factor 1/restriction factor 1 (Ref1) class of restriction factors, which block infection by targeting the capsids of diverse retroviruses. Here we show that lentivirus susceptibility factor 1 and Ref1 are species-specific variants of tripartite interaction motif 5alpha (TRIM5alpha), a cytoplasmic body component recently shown to block HIV-1 infection in rhesus macaque cells, and can indeed block infection by widely divergent retroviruses. Depletion of TRIM5alpha from human cells relieved restriction of N-tropic murine leukemia virus (N-MLV), and expression of human TRIM5alpha in otherwise nonrestricting cells conferred specific resistance to N-MLV infection, indicating that TRIM5alpha is Ref1 or an essential component of Ref1. TRIM5alpha variants from humans, rhesus monkeys, and African green monkeys displayed different but overlapping restriction specificities that were quite accurately predicted by the restriction properties of the cells from which they were derived. All TRIM5alpha variants could inhibit infection by at least two different retroviruses, and African green monkey TRIM5alpha was able to inhibit infection by no less than four divergent retroviruses of human, non-human primate, equine, and murine origin. However, each TRIM5alpha variant was unable to restrict retroviruses isolated from the same species. These data indicate that TRIM5alpha can confer broad innate immunity to retrovirus infection in primate cells and is likely to be an important natural barrier to cross-species retrovirus transmission.

Amino Acid Sequence↗