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H Huismans

Publications and source records attributed to H Huismans.

At least 37 records · Page 2Linked to original sources
PubMed1994

Vaccinia virus expression of the VP7 protein of South African bluetongue virus serotype 4 and its use as an antigen in a capture ELISA.

Recombinant vaccinia viruses expressing the VP7 core protein of South African bluetongue virus serotype 4 (SA-BTV4) were identified by polymerase chain reaction amplification. Expression of VP7 was verified by radio-immunoprecipitation and a F(ab')2-based ELISA. Antibodies to VP7 were detected in sera from sheep that had been infected with 20 different virulent BTV serotypes by using the vaccinia virus (VV) expressed VP7 as antigen in a capture ELISA. F(ab')2-immobilised VV-expressed SA-BTV4 VP7 cross-reacted with sera directed against all 9 African horsesickness virus serotypes and epizootic haemorrhagic disease virus serotype 2.

Animals↗
PubMed1994

Comparison of the expression and phosphorylation of the non-structural protein NS2 of three different orbiviruses: evidence for the involvement of an ubiquitous cellular kinase.

The non-structural protein NS2 of epizootic haemorrhagic disease (EHD), bluetongue (BT) and African horsesickness (AHS) viruses has each been expressed to high levels using a baculovirus vector gene expression system. It was found that the recombinant baculovirus-expressed EHDV NS2 protein was resolved as a doublet following PAGE. Peptide mapping of these protein bands indicated that they were identical. The difference in the sizes of the NS2 protein bands could not be attributed to the phosphorylation of NS2 or other posttranslational modification such as N-glycosylation and remains obscure. The EHDV, BTV and AHSV baculovirus-expressed NS2 proteins were all phosphorylated in vitro without the addition of an exogenous kinase. An unphosphorylated form of EHDV NS2, obtained by expressing the NS2 gene as a fusion protein in Escherichia coli cells, could be phosphorylated in vitro by a protein kinase associated with the cytoplasm of insect cells. The phosphorylated version of this protein was found to be significantly less efficient in binding ssRNA, compared to the unphosphorylated version.

Animals↗
PubMed1994

Cloning, characterization and expression of the gene that encodes the major neutralization-specific antigen of African horsesickness virus serotype 3.

The gene encoding the outer capsid protein, VP2, of African horsesickness virus serotype 3 (AHSV-3) has been sequenced in its entirety from cDNA clones of the segment 2 RNA, and compared with the previously published VP2 gene sequence of AHSV-4. AHSV-3 genome segment 2 was shown to be 3221 nucleotides in length, encoding a protein of 1057 amino acids with a 50.5% identity to the amino acid sequence of AHSV-4 VP2. Two areas of high variability (approximately 35% identity) were identified. The N-proximal variable region (amino acids 128 to 309) exhibited significant hydrophilicity, suggesting a possible role in the determination of the serotype-specific immune response. VP2 of AHSV-3 has furthermore been expressed in a baculovirus expression system. The expressed protein was shown to react specifically with an anti-AHSV-3 serum in Western blots. Antibodies raised in rabbits and guinea-pigs against the recombinant VP2 neutralized the virus in a plaque reduction assay, confirming the identity of VP2 as the major neutralization-specific antigen of AHSV.

African Horse Sickness Virus↗
PubMed1992

[Familial adenomatous polyposis from the ophthalmologic viewpoint].

Familial adenomatous polyposis is dominant autosomal heritable and pre-cancerous. Characteristic changes of ocular fundus, multiple and bilateral retinal dysplasias, permit diagnosis in presymptomatic stage, significant especially not at least for sporadic cases of polyposis recti and coli, which are 40 per-cent of all. Contrary to often wellknown risk-families this group can't be realized epidemiologically, but complications are the same.

Adenomatous Polyposis Coli↗
PubMed1992

[Study of blood flow velocity in the central retinal artery using pulsed Doppler sonography].

Using the method of pulsed-wave ultrasound-Doppler-Sonography (2 MHz-probe; sample volume 10 mm; variable invading depth by using a so-called "flow-pipe"; transmission range 10 mW/m2), the author demonstrates an objective, reproducible and exact clinical test to examine blood-circulation in central retinal artery. Because of the fact, that the angle of ultrasound is nearly zero-degrees to central retinal artery, accuracy of measurement flow velocity is nearly hundred percent. Method can be applied without problems by using intracranial Doppler-Sonography (ICD). It is less expensive than Duplex-Sonographie for instance.

Blood Flow Velocity↗
PubMed1992

["Erroneous orthograde" direction of flow in the supratrochlear artery as a cause of Doppler ultrasound diagnostic error in severe (filiform; 90%) stenosis of the carotid bifurcation].

Author reports on mistake in Ultrasound-Doppler-Sonography by an neurologist. A 82-year-old women with leftside Amaurosis fugax was referred by her family doctor, internist. Neurological examination, above all Doppler-Sonography, results in "normal findings". Examination by author however detected filiforme stenosis of left internal carotid artery in spite of "orthograde" direction of blood-flow in final branches of ophthalmic artery. This perhaps was the cause of neurological misdiagnosis.

Aged↗
PubMed1991

A comparison of the nucleotide sequences of cognate NS2 genes of three different orbiviruses.

The genes encoding nonstructural protein NS2 of African horsesickness virus (AHSV) and epizootic hemorrhagic disease virus (EHDV) were cloned, sequenced, and compared to the NS2 gene of bluetongue virus (BTV). Nucleotide similarity ranged from 53 to 60%. The length of the proteins varied from 376 amino acids (EHDV) to 365 amino acids (AHSV). The N-terminal half of NS2 is more conserved (+/- 58% similarity) among the three orbiviruses, while the C-terminal half contains a 120 amino acid region of low similarity (18%). The variable region has a high content of alpha-helix conformation and a hydrophilic character. A short region of 9 amino acids contains 5 amino acids that are either similar or identical in single-stranded RNA binding proteins of BTV, EHDV, AHSV, reovirus and rotavirus.

African Horse Sickness Virus↗
PubMed1991

A comparison of different genomic probes in the detection of virus-specified RNA in Orbivirus-infected cells.

Different 32P-labelled genomic probes of bluetongue virus (BTV), epizootic haemorrhagic disease virus (EHDV) and equine encephalosis virus (EEV) were compared with respect to the detection of virus-specified RNA in infected cells. The probe derived from the genome segment that encodes nonstructural protein NS1 was found to be the most sensitive, detecting virus-specified RNA in glutaraldehyde-fixed cells as early as 2-3 h p.i. This comparison was based on the observation that the NS1 gene probe required a smaller number of infected cells to produce a positive hybridization signal than the other nucleic acid probes. The only exception was the EHDV NS2 gene probe which appeared to be as sensitive as the NS1 gene probe. The advantage of using the NS1 gene probe was particularly evident in the analysis of cells infected at very low multiplicities of infection. At a multiplicity of infection of 1 x 10(-5) plaque forming units/cell, virus-specified RNA could be detected 48 h after infection. The greater sensitivity of the NS1 gene-specific probe is ascribed to the fact that its target, the NS1 mRNA, is transcribed more frequently than the other target viral mRNAs. The major application of the cell-hybridization method is the rapid detection of small quantities of infectious virus particles.

Animals↗
PubMed1991

A characterization of the nonstructural protein from which the virus-specified tubules in epizootic haemorrhagic disease virus-infected cells are composed.

The complete nucleotide sequence of segment 6 of epizootic haemorrhagic disease virus serotype 2 (Alberta) which encodes nonstructural protein NS1 was determined from a cDNA clone containing a full-length copy of the gene. The gene was found to be 1806 bp in length, constituted by one open reading frame of 1656 bp which is flanked by 5' and 3' noncoding regions of 32 and 118 bp, respectively. The conserved 5' and 3' terminal hexanucleotide sequences were identical to those of BTV-10. The 5' noncoding nucleotide sequences of cognate genome segments 4, 6 and 8 were found to be highly conserved in EHDV-2 and BTV-10. The 3' noncoding regions are less conserved but share common characteristics. The predicted EHDV-2 NS1 gene product, a 552 amino acid polypeptide, is predominantly hydrophobic and has a net charge of +5 at neutral pH. Comparison to its BTV-10 counterpart revealed a high degree of homology. Regions of high amino acid similarity were shown to correlate with hydrophobic domains on the proteins whilst regions of lower amino acid similarity corresponded with the hydrophilic domains. Thirteen conserved cysteine residues of which the majority occurred in hydrophobic regions with more than 80% amino acid similarity were identified.

Amino Acid Sequence↗
PubMed1991

Synthesis of the virus-specified tubules of epizootic haemorrhagic disease virus using a baculovirus expression system.

The formation of virus-specific tubules is one of the most characteristic features in the orbivirus infection cycle, yet little is known about their role in virus replication. The tubuli are composed of a major nonstructural protein, NS1. We have investigated the expression of the NS1-encoding gene of epizootic haemorrhagic disease virus serotype 2 (Alberta-strain) by producing a recombinant Autographa californica nuclear polyhedrosis virus (AcNPV). Prior to cloning in the baculovirus transfer vector, pAcYM1 and cotransfection with AcNPV DNA, the NS1 gene was tailored by means of a polymerase chain reaction method to remove G/C tails. The baculovirus recombinant, AcNPV-EHDV2 NS1, expressed large amounts of a 55 K protein which could be purified by sucrose gradient sedimentation as a tubular complex. It appeared that the tubules could break up into 50 nm diameter circular units, which in turn were composed of approximately 16 subunits. The circular units appeared to be hollow and stacked on top of one another (100 units/micron tubule length), giving the tubules a segmented, ladderlike appearance. A large excess of EHDV2-specific tubuli could also be demonstrated in AcNPV-EHDV2 NS1-infected Spodoptera frugiperda cells by electron microscopic examination of thin sections. With pulse-labelling experiments it was shown that, regardless of the level of NS1 expression, the majority of NS1 synthesized in a 30 min period could only be recovered in a particulate form.

Animals↗
PubMed1991

[Homonymous hemianopsia as an unusual leading symptom in chronic subdural hematoma].

Author reports on a 82-years old man with two chronic subdural hematomas after head-trauma 4 weeks ago: one above right cerebral hemisphere with light displacement of median line, light compression of side-ventricle, too. A second one fronto-temporal above left hemisphere, smaller than the other one. Defect of visual field was the only neuro-ophthalmologic sign.

Aged↗
PubMed1991

[Conspicuous change of refraction in endocrine orbitopathy].

Author reports on 2 women, 42 respectively 58 years old, with Graves' Ophthalmopathy. In both cases acute considerable change of refraction was noticed: progression of preexistent myopia. Author suggests edema and infiltration of lymphocytes and plasmacyts of ciliary-body, pathologic-anatomical substratum of the most changes of orbita in this disease, responsible for etiology.

Adult↗
PubMed1991

[Artificial compression of the superficial temporal artery by faulty eyeglasses (frame) position. A hemodynamically significant phenomenon].

Temporal superficial artery is clinically important, angiological primarily as collateral vessel in stenosis or obstruction of internal carotid vessel. Author describes artificial compression of both temporal superficial arteries by deficient spectacale-bows. There was relevant hemodynamic irritation of perfusion in dopplersonographic examination cranial of compressed vessel, which normalized after restitution. Supposing in case internal carotid artery was obstructed there would be a dangerous situation.

Aged↗
PubMed1991

A comparison of the genes which encode non-structural protein NS3 of different orbiviruses.

The segment 10 (S10) genes of African horsesickness virus (AHSV), Palyam virus and epizootic haemorrhagic disease virus were translated in vitro in a rabbit reticulocyte lysate system. Each of the S10 genes encoded two proteins NS3 and NS3A, which were shown to be related by peptide mapping. Cloned copies of the S10 genes of two AHSV serotypes (AHSV-3 and AHSV-9) and Palyam virus were sequenced and compared to each other and to the nucleotide sequence of bluetongue virus (BTV) gene S10. Two in-phase ATG translation initiation codons reported for the S10 genes of BTV-10 and BTV-1 were conserved in the S10 genes of AHSV-3, AHSV-9 and Palyam virus, and would be able to initiate synthesis of NS3 and NS3A respectively. Comparison of the amino acid sequences of NS3 of AHSV-3 and AHSV-9 identified two areas of approximately 45 amino acids which displayed high (98%) similarity. One of these areas corresponded to the only region which displayed more than 50% amino acid similarity between NS3 of BTV, AHSV and Palyam virus. This region could represent an important structural or catalytic site of the protein. The overall amino acid similarity outside this conserved region was between 13% and 29%.

Amino Acid Sequence↗
PubMed1990

A comparison of different cloned genome segments of epizootic haemorrhagic disease virus as serogroup-specific probes.

The eight largest double-stranded (ds) RNA genome segments of epizootic haemorrhagic disease virus (EHDV) serotype 2 (Alberta strain) have been cloned. Of these, segments 4, 5, 6, 7, and 8 are represented by clones that correspond in size to those predicted for full-length clones. The different clones were used as nucleic acid probes to study the nucleic acid homology of cognate genes of four different EHDV serotypes. The results indicated that the 4 isolates may be subdivided in two geographic groups which include Ibaraki virus as the sole member of one group and EHDV1 (New Jersey), EHDV2 (Alberta) and EHDV6 (XBM 67--isolated in South Africa) as a second. Genome segments 1, 3, 4, 6, and 8 were found to be highly conserved with more than 90% homology amongst cognate genes of three of the members of the EHDV serogroup. Of these, segments 1 and 3 showed the largest degree of homology with cognate genes of members of the BTV serogroup. Segment 6 and 8 probes of EHDV2 (Alberta) on the other hand did not hybridize with BTV dsRNA under conditions of moderate to low stringency and are recommended for use as EHDV group-specific probes.

Autoradiography↗
PubMed1990

[Dominant inheritance of pupillary pigment cysts. A follow-up study].

In 1969 Meyer described in this journal a family suffering from multiple congenital pigmented pupillary cysts with dominant mode of inheritance. The therapy--total iridectomy and photocoagulation of the cysts--resulted in only a temporary improvement in visual acuity. The cysts were between 1.5 and 5.0 mm in diameter. The present author recently examined a member of this family with severe contusion of the left eyeball. The trauma had evidently opened the residual embryonal ring sinus of the fetal iris system (von Szily). While the traumatic mydriasis persisted, the cysts did not refill.

Adolescent↗