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K Hendrickx

Publications and source records attributed to K Hendrickx.

7 recordsLinked to original sources
PubMed1999

Proximal segment position after distraction with the MD-DOS device.

We investigated cephalometrically the movement of the proximal segment in the sagittal plane in patients treated with distraction (MD-DOS device) for mandibular lengthening. The proximal segment was anteriorly rotated, whilst the distal segment was posteriorly rotated after the lengthening procedure. Thus the angle of the jaw was advanced half the distance of the advancement of the distal segment. One possible reason for the anterior rotation of 3.3 degrees on average is the repositioning of the proximal segment during application of the anterior fixation unit in the cases where mobilization was complete. Another more plausible reason is the anterior pull by the masticatory muscles and elastic bands being greater than the reactive distraction vector component in concert with a flexible telescopic distraction module and a single posterior screw anchorage. The positional movements of both distal and proximal segments were similar to those observed after mandibular advancement with bilateral sagittal split osteotomies.

Adolescent↗
PubMed1997

Cloning and characterization of Manduca sexta and Plutella xylostella midgut aminopeptidase N enzymes related to Bacillus thuringiensis toxin-binding proteins.

We report the purification, cloning and characterization of an aminopeptidase N from the midgut epithelium of Manduca sexta that binds Cry1Ab5, an insecticidal crystal protein [ICP] from Bacillus thuringiensis. Sequence information derived from this M. sexta aminopeptidase N was used for the cloning of an aminopeptidase N from the midgut brush-border membrane of Plutella xylostella, an insect species of which some populations acquired resistance against Cry1Ab5. Affinity chromatography on a Cry1Ab5 matrix was used to isolate a 120-kDa glycoprotein from the larval midgut of the lepidopteran M. sexta. On ligand blots the purified 120-kDa protein discriminates between the lepidopteran-specific Cry1Ab5 and the coleopteran-specific Cry3A delta-endotoxin. Internal amino acid sequences from the 120-kDa protein were used for the design of degenerate oligonucleotides. From a nested PCR with M. sexta midgut cDNA as template, a DNA fragment was obtained which shows similarity to prokaryotic and eukaryotic aminopeptidase N genes. This PCR fragment was used to screen cDNA libraries of larval midguts from M. sexta and P. xylostella. From the M. sexta midgut cDNA library a 2973-bp nucleotide sequence was cloned. The ORF of the sequence encodes a 942-residue aminopeptidase N (M. sexta Apn2) containing two hydrophobic regions. The NH2-terminal hydrophobic region corresponds to a secretory signal sequence and the COOH-terminal hydrophobic region is typical of glycosylphosphatidylinositol (glycosyl-PtdIns)-anchored proteins. Low-stringency hybridization of the P. xylostella midgut cDNA library with M. sexta apn2 probes enabled the isolation of a 3118-bp sequence with an ORF encoding a 946-residue preproprotein. This aminopeptidase N (P. xylostella Apn1) displays 61% amino acid identity to M. sexta Apn2 and contains a COOH-terminal signal peptide for glycosyl-PtdIns anchor addition. Both M. sexta Apn2 and P. xylostella Apn1 contain four Cys residues, which are highly conserved among eukaryotic aminopeptidase N molecules. Treatment of Sf9 cells expressing the P. xylostella apn1 gene with PtdIns-specific phospholipase C demonstrated that P. xylostella Apn1 is attached to the insect cell membrane by a glycosyl-PtdIns anchor.

Amino Acid Sequence↗
PubMed1997

False positive immunostaining of Locusta neurosecretory cells with a variety of preimmune sera.

A large number of antisera directed against vertebrate neuropeptides have been reported to yield positive staining when applied to insect brains. In most cases, the preimmune serum of the same animal in which the antiserum was developed is not available for testing in control experiments. We have experienced that a large percentage of preimmune sera, as well as a culture medium for hybridomas, stain cell populations and fibers in the central nervous system of the insect Locusta migratoria. Purification of these preimmune sera on a Protein A and Protein G support indicates that the reaction is due to preexisting antibodies of the IgG class. Western analysis of brain and nervous tissue extracts indicates the presence of two immunoreactive 27-kDa bands. These bands could also be visualized in other tissue extracts such as muscle, midgut, Malpighian tubules, and fat body of Locusta. The brain of other insect species, such as Periplaneta americana, Leucophaea maderae, and Neobellieria bullata were devoid of the false immunopositive reaction. There is no easy way to eliminate this type of immunoreaction. It follows that when affinity chromatographic purification of the antibody is not feasible, it is essential to include in the control procedure, the preimmune serum of the animal that was used for the production of the antiserum. This means that it should become common practice to sell or exchange sera together with their corresponding preimmune sera.

Animals↗
PubMed1990

Effects of Bacillus thuringiensis delta-endotoxin on the permeability of brush border membrane vesicles from tobacco hornworm (Manduca sexta) midgut.

1. The effect of two recombinant Bacillus thuringiensis delta-endotoxins on brush border membrane vesicles of Manduca sexta midgut was investigated using an in vitro assay system, based on ion-amino acid cotransport. 2. A CryIA(b)-toxin provoked an increase in the permeability of the vesicles. 3. A CryIB-toxin, not toxic to M. sexta larvae in vivo, had no effect in our assay. 4. In contrast to earlier reports, the increase in permeability was found to be neither selective for K+ nor specifically inhibited by Ca2+ or Ba2+. 5. Our data support the hypothesis that B. thuringiensis delta-endotoxins create non-specific pores.

Alanine↗
PubMed1988

Early versus late tocolytic treatment for preterm premature membrane rupture.

The effect of tocolytic therapy before labor was evaluated in 33 pregnant women with preterm premature rupture of the membranes. Either intravenous magnesium sulfate or oral terbutaline was administered at the time of presentation. Intensive surveillance to detect signs of infection was carried out for all patients. In 29 of the patients in this treatment group who were seen at less than 34 weeks, a significantly longer prolongation of pregnancy was achieved when compared with 24 similar women treated after onset of labor in the hospital (169 hours versus 77 hours, p = 0.05). Duration of infant hospitalization was less for those mothers receiving tocolytic agents before labor. Maternal and infant infection were not different in the two groups; nor was the cesarean section rate. When this treatment group was compared with another control group of 96 women already in labor at presentation, the difference in time from admission to delivery was substantial, but it did not achieve statistical significance. In this group the rate of maternal infection was significantly higher, but newborn morbidity was not. Aggressive early treatment with tocolytic agents in pregnant women with preterm premature membrane rupture is more productive but not more dangerous than conservative management.

Female↗
PubMedDate not supplied

[Analysis of severely injured patients admitted via an emergency service].

Data about the number and treatment of trauma-patients are, certainly in our country, very rare. In this study we showed that such a registration with grading of the severity of the injuries following the ISS-Score is feasible and useful. Further and more extensive registration seems necessary in order to obtain a better insight in epidemiology and treatment of trauma patients in our country.

Adolescent↗