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H Rinder

Publications and source records attributed to H Rinder.

46 records · Page 3Linked to original sources

Diagnostic DNA amplification from individual tick eggs, larvae and nymphs.

The species of single tick eggs, larvae and nymphs was determined by PCR amplification and characterization of the hypervariable, second transcribed spacer (ITS2) of the multicopy ribosomal RNA gene (rDNA). Engorgement of larvae and nymphs did not preclude species identification. The method is generally applicable for ixodid and argasid ticks and can be used for epidemiological studies requiring the identification of individuals from pre-adult stages.

Animals↗

Genetic evidence against a morphologically suggestive conspecificity of Dermacentor reticulatus and D. marginatus (Acari:Ixodidae).

International Journal for Parasitology 25: 1413-1419. Dermacentor reticulatus and D. marginatus exhibit overlapping phenotypes. The possibility of conspecificity was investigated on the nucleotide level by comparing DNA sequences of the second internal transcribed spacer (ITS 2) of the rDNA gene. The inter-specific polymorphism was more than 20-times greater than the intra-specific polymorphism of 3 D. reticulatus strains of different geographic origins. Furthermore, the degree of polymorphisms between D. reticulatus and D. marginatus was found to be of the same order of magnitude as that between D. andersoni and D. variabilis, for which separate species status is accepted. These genomic findings do not support a possible conspecificity of D. reticulatus and D. marginatus.

Animals↗

Lymphocyte adhesion-dependent calcium signaling in human endothelial cells.

Vascular endothelial cells (ECs) can undergo dramatic phenotypic and functional alterations in response to humoral and cellular stimuli. These changes promote endothelial participation in the inflammatory response through active recruitment of immune effector cells, increased vascular permeability, and alteration in vascular tone. In an attempt to define early events in lymphocyte-mediated EC signaling, we investigated cytosolic-free calcium (Ca2+) changes in single, Fluo-3-labeled human umbilical vein ECs (HUVECs), using an ACAS interactive laser cytometer. Of all lymphocyte subsets tested, allogeneic CD3-, CD56+ natural killer (NK) cells uniquely elicited oscillatory EC Ca2+ signals in cytokine (interleukin [IL]-1- or tumor necrosis factor [TNF])-treated ECs. The induction of these signals required avid intercellular adhesion, consisted of both Ca2+ mobilization and extracellular influx, and was associated with EC inositol phosphate (IP) generation. Simultaneous recording of NK and EC Ca2+ signals using two-color fluorescence detection revealed that, upon adhesion, NK cells flux prior to EC. Lymphocyte Ca2+ buffering with 1,2-bis-5-methyl-amino-phenoxylethane-N,N,N'-tetra-acetoxymethyl acetate (MAPTAM) demonstrated that lymphocyte fluxes are, in fact, prerequisites for the adhesion-dependent EC signals. mAb studies indicate that the beta 2 integrin-intercellular adhesion molecule (ICAM)-1 adhesion pathway is critically involved. However, ICAM-1 antisense oligonucleotide inhibition of IL-1-mediated ICAM-1 hyperinduction had no effect on EC Ca2+ signaling in lymphocyte-EC conjugates, indicating that additional cytokine-induced EC alteration is required. These experiments combine features of lymphocyte-endothelial interactions, intercellular adhesion, EC cytokine activation and transmembrane signaling. The results implicate the IP/Ca2+ second messenger pathway in EC outside-in signaling induced by cytotoxic lymphocytes, and suggest that these signals may play a role in EC alteration by lymphocyte adhesion.

Base Sequence↗

Intra- and interspecific polymorphisms of Leishmania donovani and L. tropica minicircle DNA.

A pair of degenerate polymerase chain reaction (PCR) primers (LEI-1, TCG GAT CC[C,T] [G,C]TG GGT AGG GGC GT; LEI-2, ACG GAT CC[G,C] [G,C][A,C]C TAT [A,T]TT ACA CC) defining a 0.15-kb segment of Leishmania minicircle DNA was constructed. These primers amplified not only inter- but also intraspecifically polymorphic sequences. Individual sequences revealed a higher intraspecific than interspecific divergence. It is concluded that individual sequences are of limited relevance for species determination. In contrast, when a data base of 19 different sequences was analyzed in a dendrographic plot, an accurate species differentiation was feasible.

Animals↗

Direct amplification and differentiation of pathogenic and nonpathogenic Entamoeba histolytica DNA from stool specimens.

Discrimination of pathogenic and nonpathogenic Entamoeba histolytica is of great clinical importance. A simple and rapid DNA extraction method that can be used directly with stool specimens was developed without the need for prior cultivation of the parasites. The entire protocol can be performed at room temperature in a 1.5-ml microcentrifuge tube format. There is no DNA precipitation step. The subsequent nested polymerase chain reaction consists of an initial E. histolytica-specific amplification, followed by two separate amplifications using two primer pairs specific for pathogenic and nonpathogenic E. histolytica, respectively. Amplification products can be verified by restriction endonuclease digests. There is no need for hybridizations or the use of radionucleotides. One trophozoite per milligram of stool sample could be detected and differentiated in a 0.1-g specimen.

Animals↗

Ependymins from the cerebrospinal fluid of salmonid fish: gene structure and molecular characterization.

So far, ependymins (Epds) have been sequenced only from cypriniform fish, and in the past all attempts have failed to characterize, on a molecular level, homologous Epd proteins in higher vertebrates. Therefore, rainbow trout (Oncorhynchus mykiss) Epds, which represent the predominant proteins of the cerebrospinal fluid, have been N-terminally sequenced and the encoding cDNA subsequently cloned using the polymerase chain reaction. Surprisingly, only 40-42% of the amino acids are identical with the corresponding sequences from goldfish (Carassius auratus), and no convincing immunological cross-reactivity is observed with an antiserum raised against purified Epds from C. auratus. O. mykiss possesses two highly homologous genes encoding Epds (Om-I, Om-II), a feature typical of a quasi-tetraploid species. Western analysis, using two specific antibodies against Epds from O. mykiss, revealed a variety of different glycosylation variants. In contrast to C. auratus, Epds from O. mykiss probably do not form disulfide-linked dimers. The structure of one Epd gene and its flanking regions have been determined for the Atlantic salmon (Salmo salar). Six exons were deduced by comparison with the corresponding cDNA sequence from O. mykiss (almost 98% homology with Om-II).

Amino Acid Sequence↗

Molecular analysis of the ependymin gene and functional test of its promoter region by transient expression in Brachydanio rerio.

Ependymins are secretory products of meningeal cells and represent the predominant glycoproteins in the cerebrospinal fluid from various orders of teleost fish. In the zebrafish, their expression starts between 48 and 72 h post-fertilization. Generally, they share characteristics with proteins involved in cell-contact phenomena. Here, we characterize the ependymin gene from Brachydanio rerio and its flanking regions. The sequence was obtained from clones generated using the polymerase chain reaction (PCR), including a variation of an "anchored" PCR. Also, clones from a conventional phage library were analyzed. We found that the transcribed portion is arranged in six exons. Transient expression of an ependymin-promoter-lacZ gene fusion in zebrafish embryos revealed that the 2.0-kb upstream regulatory region used is sufficient to direct the ependymin-specific correct temporal and spatial expression pattern of the lacZ reporter gene.

Amino Acid Sequence↗

Pharmacology and biological efficacy of a recombinant, humanized, single-chain antibody C5 complement inhibitor in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass.

BACKGROUND: Cardiopulmonary bypass (CPB) induces a systemic inflammatory response that causes substantial clinical morbidity. Activation of complement during CPB contributes significantly to this inflammatory process. We examined the capability of a novel therapeutic complement inhibitor to prevent pathological complement activation and tissue injury in patients undergoing CPB. METHODS AND RESULTS: A humanized, recombinant, single-chain antibody specific for human C5, h5G1.1-scFv, was intravenously administered in 1 of 4 doses ranging from 0.2 to 2.0 mg/kg before CPB. h5G1.1-scFv was found to be safe and well tolerated. Pharmacokinetic analysis revealed a sustained half-life from 7.0 to 14.5 hours. Pharmacodynamic analysis demonstrated significant dose-dependent inhibition of complement hemolytic activity for up to 14 hours at 2 mg/kg. The generation of proinflammatory complement byproducts (sC5b-9) was effectively inhibited in a dose-dependent fashion. Leukocyte activation, as measured by surface expression of CD11b, was reduced (P<0.05) in patients who received 1 and 2 mg/kg. There was a 40% reduction in myocardial injury (creatine kinase-MB release, P=0.05) in patients who received 2 mg/kg. Sequential Mini-Mental State Examinations (MMSE) demonstrated an 80% reduction in new cognitive deficits (P<0.05) in patients treated with 2 mg/kg. Finally, there was a 1-U reduction in postoperative blood loss (P<0. 05) in patients who received 1 or 2 mg/kg. CONCLUSIONS: A single-chain antibody specific for human C5 is a safe and effective inhibitor of pathological complement activation in patients undergoing CPB. In addition to significantly reducing sC5b-9 formation and leukocyte CD11b expression, C5 inhibition significantly attenuates postoperative myocardial injury, cognitive deficits, and blood loss. These data suggest that C5 inhibition may represent a novel therapeutic strategy for preventing complement-mediated inflammation and tissue injury.

Antibodies, Monoclonal↗

Rapid, simple, and culture-independent detection of rpsL codon 43 mutations that are highly predictive of streptomycin resistance in Mycobacterium tuberculosis.

The substitution of codon 43 in the gene rpsL is the single most common mutation found in streptomycin-resistant Mycobacterium tuberculosis. The characterization of this mutation has been hampered by the need for prior cultivation of the mycobacteria, the need for DNA sequencing, or both. In this report we describe a simple and culture-independent technique to detect this mutation directly from sputum samples, requiring little more than a polymerase chain reaction (PCR) machine and a simple agarose minigel. There is no need for labeled probes or DNA sequencing. In a preliminary test of feasibility, interpretable results were obtained from all of 16 smear-positive and 1 of 4 smear-negative, culture-positive samples. Two of two samples containing M. tuberculosis with rpsL codon 43 mutations were correctly identified.

Antibiotics, Antitubercular↗