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J Henke

Publications and source records attributed to J Henke.

At least 37 records · Page 2Linked to original sources
PubMed2001

Application of Y-chromosomal STR haplotypes to forensic genetics.

This paper delivers population genetic data on Y-chromosomal short tandem repeat (STR) polymorphisms along with reports of unusual observations and casework. Population studies were carried out on the Y-specific STR polymorphisms DYS19, DYS385 I+II, DYS389 I+II, DYS390, DYS391, DYS392, and DYS393 in population samples from North India, Turkey, and Germany. In all three populations the vast majority of haplotypes was observed only once, especially in the Turkish group. Highly unusual cases are reported. In a German individual, we observed the variant allele DYS392*11.1, whereas a Turkish haplotype revealed a duplication at locus DYS19. Application of Y-chromosomal STR markers to forensic genetics was demonstrated in two cases: 1) a deficient paternity case, and 2) a father/son pair, where the Amelogenin primers failed to amplify the Y-homolog. In forensic genetics, Y-chromosomal STR polymorphisms are highly welcomed as an additional tool.

Female↗
PubMed2000

Malignant hyperthermia mutation Arg615Cys in the porcine ryanodine receptor alters voltage dependence of Ca2+ release.

Ca2+ inward current and fura-2 Ca2+ transients were simultaneously recorded in porcine myotubes. Myotubes from normal pigs and cells from specimens homozygous for the Arg615Cys (malignant hyperthermia) mutation of the skeletal muscle ryanodine receptor RyR1 were investigated. We addressed the question whether this mutation alters the voltage dependence of Ca2+ release from the sarcoplasmic reticulum. The time course of the total flux of Ca2+ into the myoplasm was estimated. Analysis showed that the largest input Ca2+ flux occurred immediately after depolarization. Amplitude and time course of the Ca2+ flux at large depolarizations were not significantly different in the Arg615Cys myotubes. Ca2+ release from the sarcoplasmic reticulum was activated at more negative potentials than the L-type Ca2+ conductance. In the controls, the potentials for half-maximal activation V 1/2 were -9.0mV and 16.5 mV, respectively. In myotubes expressing the Arg615Cys mutation, Ca2+ release was activated at significantly lower depolarizing potentials (V = -23.5 mV) than in control myotubes. In contrast, V of conductance activation (13.5 mV) was not significantly different from controls. The specific shift in the voltage dependence of Ca2+ release caused by this mutation can be well described by altering a voltage-independent reaction of the ryanodine receptor that is coupled to the voltage-dependent transitions of the L-type Ca2+ channel.

Amino Acid Substitution↗
PubMed2000

Characteristics and frequency of germline mutations at microsatellite loci from the human Y chromosome, as revealed by direct observation in father/son pairs.

A number of applications of analysis of human Y-chromosome microsatellite loci to human evolution and forensic science require reliable estimates of the mutation rate and knowledge of the mutational mechanism. We therefore screened a total of 4,999 meioses from father/son pairs with confirmed paternity (probability >/=99. 9%) at 15 Y-chromosomal microsatellite loci and identified 14 mutations. The locus-specific mutation-rate estimates were 0-8. 58x10-3, and the average mutation rate estimates were 3.17x10-3 (95% confidence interval [CI] 1.89-4.94x10-3) across 8 tetranucleotide microsatellites and 2.80x10-3 (95% CI 1.72-4.27x10-3) across all 15 Y-chromosomal microsatellites studied. Our data show a mutational bias toward length increase, on the basis of observation of more repeat gains than losses (10:4). The data are in almost complete agreement with the stepwise-mutation model, with 13 single-repeat changes and 1 double-repeat change. Sequence analysis revealed that all mutations occurred in uninterrupted homogenous arrays of >/=11 repeats. We conclude that mutation rates and characteristics of human Y-chromosomal microsatellites are consistent with those of autosomal microsatellites. This indicates that the general mutational mechanism of microsatellites is independent of recombination.

Adolescent↗
PubMed2000

Molecular analysis of the human orosomucoid gene ORM1*Q0köln responsible for incompatibility in a German paternity case.

In a German paternity test, an alleged father was excluded only by reverse homozygosity of ORM1 phenotypes (mother ORM1 S, child ORM1 S and alleged father ORM1 F1) out of the 28 classical and DNA markers investigated. Without the ORM1 system the biostatistical probability of paternity was calculated to exceed 99.999%. The intensity of the immunoprinted bands of the ORM1 protein for the child and alleged father after isoelectric focusing appeared to be reduced to about half. To identify a possible null allele, gene-specific amplification followed by single-strand conformation polymorphism and sequencing analyses were carried out. Deletion of one of the two copies of a 4 bp direct repeat sequence (GTCT) in exon 4 of the consensus sequence of ORM1*F1 was observed in the child and alleged father. Thus, the sharing of a rare mutant gene, ORM1*Q0köln, increased the probability of paternity.

DNA Mutational Analysis↗
PubMed2000

Acute electrophysiologic effects and antifibrillatory actions of the long linear lesions in the right atrium in a sheep model.

UNLABELLED: Linear lesions (LL) represent an option for curing of atrial fibrillation (AF) with ablation techniques. METHODS AND RESULTS: In 11 sheep (w. 72+/-16 kg), LL were created with radiofrequency ablation in the lateral, posterior and septal walls of the right atrium (RA). AF was induced before and after LL with burst pacing. Mapping of the AF was performed with a 64-electrode basket catheter deployed in the RA. Quantitative analysis was performed with a custom-made software program. LL were confirmed histologically 7 to 10 days after the procedure. LL were transmural in 78% of their length. Stimulation thresholds and right atrial activation times were increased after LL compared to preablation values. Effective refractory periods of the RA were prolonged significantly in 7 out of 12 regions after generation of LL. Conduction velocities in the RA segments between LL were reduced in lateral, posterior and septal walls. During paced rhythms double potentials were recorded in all animals. AF could be induced in all animals of this model despite the presence of LL in the RA. AF episodes were significantly more regular after LL throughout the RA due to a significant reduction of the number of the wave fronts in the RA. During AF episodes, in the presence of LL, the RA was driven by wave fronts of left atrial origin entering the right side of the septum through interatrial connections. CONCLUSIONS: 1) LL profoundly affect electrophysiologic parameters of RA. 2) In the presence of LL, AF manifest a higher degree of regularity as compared to preablation episodes. 3) Dissociation between wave fronts of left atrial origin entering the RA through the interatrial connections is an important mechanism of the antifibrillatory action of the septal LL.

Animals↗
PubMed2000

Endohyperthermia--experimental evaluation of a new therapeutic approach for treatment of biliary carcinoma.

BACKGROUND AND STUDY AIMS: To improve the prognosis of patients with unresectable, locally advanced bile duct carcinoma, new treatment strategies need to be evaluated. Hyperthermia has been successfully applied as part of multimodal therapy in esophageal and rectal carcinoma. We performed in-vitro and in-vivo experiments with a new intraluminal hyperthermia system in the biliary tract. METHODS: A radiofrequency system (13.56 MHz, Endoradiotherm XERT-200A; Olympus Optical Co., Tokyo, Japan) was used with a special intraluminal microelectrode (diameter 4.5 mm, length 40 mm) covered by a silicone balloon with cooling water and a large counter electrode for focusing the electromagnetic field around the electrode. The heating capacity of the endohyperthermia unit was examined in vitro in a muscle-equivalent phantom (agar 4 %), in isolated livers of pigs and cows, as well as in vivo in anesthetized sheep. Continuous thermometry was done with thermosensors at the applicator surface, and with multichannel thermocouple probes in the environment of the applicator. RESULTS: Endohyperthermia induced a homogeneous heating of the phantom and the isolated liver bile duct preparation to a temperature > or = 40 degrees C in an area at least 10 mm in depth. After placement of the applicator into the common bile duct of anesthetized sheep, endohyperthermia led to a consistent and repeatable heating of the surrounding tissue to 40.5 +/- 0.5 degrees C at 1 cm distance, and 39.9 +/- 0.7 degrees C at 2 cm distance. Blood pressure, heart rate, and systemic temperature did not change in vivo. Histological examination of the bile duct showed superficial mucosal necrosis (depth 100-200 microm), microvascular damage with petechiae, congestion and edema of the bile duct wall and adventitia after hyperthermia treatment in vivo. CONCLUSIONS: The intraluminal endohyperthermia system produces consistent and repeatable heating of the surrounding tissue. Since effective thermal power can reach a depth of up to 2 cm, tumors may also be heated adequately.

Animals↗
PubMed2000

[Telemetric impedance analysis of the liver: evaluation of a noninvasive device for diagnosis of acute graft rejection after experimental liver transplantation].

Allograft rejection and its differentiation from other causes of organ dysfunction remains a diagnostic problem in liver transplant patients. Currently, acute rejection can be prevented only by a combination of diagnostic and therapeutic modalities. The diagnostic potential of a novel implantable telemetric rejection monitoring device has been assessed on the basis of the noninvasive impedance analysis in normal and liver transplanted pigs. The electric impedance data were correlated with biochemical and histological parameters. Acute rejection was correctly predicted in n = 4, and correctly excluded in n = 32, biopsy-related impedance recordings (p = 0.004). A correlation between impedance measurements and severity of histological findings r = 0.84; p = 0.0001) was confirmed. Only the biochemical parameters SGLDH and serum bilirubin revealed a comparable correlation. Impedance gradient analysis revealed evidence of a physiological relationship between liver function and the electrical properties of the organ. Telemetric impedance analysis would appear a promising means of assessing acute rejection noninvasively.

Animals↗
PubMed2000

Predictors of cigarette smoking and smoking cessation among adults with asthma.

OBJECTIVES: This study sought to determine the predictors of smoking and time until smoking cessation in a cohort of adults with asthma. METHODS: Adults with asthma (n = 374) in northern California completed structured telephone interviews at baseline and 18-month follow-up. RESULTS: Of the 374 subjects, 156 reported ever having smoked, and 39 indicated that they currently smoked. Earlier birth cohort, lower educational attainment. White race, and presence in childhood residence of an adult who smoked were associated with a greater risk of ever smoking. Lower educational attainment, early smoking initiation, higher daily cigarette consumption, and late-childhood-onset asthma were associated with a longer interval until smoking cessation. CONCLUSIONS: Persons with asthma at high risk of cigarette smoking and delayed quitting can be identified on the basis of clinical and demographic characteristics.

Adult↗
PubMed1999

Usefulness of conventional blood groups, DNA-minisatellites, and short tandem repeat polymorphisms in paternity testing: a comparison.

A total of 215 paternity cases were analysed after testing 24 marker systems. Despite technical advantages of polymerase chain reaction related polymorphisms (automatisation, employment of robots, lesser requirements concerning of quality and quantity of DNA) it could be shown that the exclusive employment of a parentage testing kit is compromised by an increased risk of erroneous conclusions. It is estimated that in about 3-4% of the cases ambiguous situations have to be expected which are caused by the occurrence of single or double exclusions. In these cases it is impossible to decide whether the exclusions indicate either true nonpaternity or a de novo mutation. The situation might become even more complicated if an involvement of a close relative of the alleged father cannot be ruled out. We cautiously advance the hypothesis that in parentage testing DNA minisatellite polymorphisms from an optimal set of tools.

Blood Grouping and Crossmatching↗
PubMed1999

Work dynamics of adults with asthma.

BACKGROUND: Asthma has been found to be among the most common conditions in the working age population and is among the most common causes of work limitation, but we could find no longitudinal studies of employment among persons with this condition. METHODS: A panel of 601 persons with a diagnosis of asthma from random samples of northern California pulmonologists and allergy-immunologists were interviewed as many as three times at 18-month intervals by a trained survey worker to report on the severity of disease, demographic characteristics, and the extent of their employment. Their employment was then compared to that of a matched sample from the U.S. Bureau of the Census Current Population Survey. RESULTS: Ninety-two percent of the persons with asthma had worked at some point prior to study enrollment. Among persons with onset during adulthood, only 29% of those who were not employed at disease onset were working at study enrollment, compared to 68% among those who were employed. Among the 420 persons interviewed three times, 75, 81, and 75%, respectively, were employed as of the three interviews. Among these 420, 66% were continuously employed and 15% were continuously not employed. The principal determinants of continuity of employment were demographic and employment characteristics, not medical ones. The employment rate and hours of work per week and per year of the persons with asthma were similar to the matched sample. CONCLUSIONS: Asthma has not substantially impeded the employment of the persons with asthma we studied, with the exception that those who were not employed at disease onset continued to have low employment rates.

Adolescent↗
PubMed1999

Investigations on the intestinal availability of native thiamin in selected foods and feedstuffs.

The aim of the present study was to investigate the precaecal digestibility as a quantitative measure for the intestinal availability of naturally occurring thiamin from selected foods and feedstuffs. Therefore, three experiments were conducted to examine the following foods and feedstuffs: Eggs, bananas, white cabbage, corn, milk, fish, barley, soybeans, rice, wheat bran, brewer's yeast, rye and soybean meal. The foods and food processing procedures were made with regard to their relevance in human and animal nutrition. For all experiments male pigs with an initial live weight between 33 and 40 kg were fitted with an end-to-end ileo-rectal anastomosis with preserved ileo-caeco-colicvalve. Three weeks after surgery, the digestibility trials were carried out from week 4 to week 9 and week 12 to week 17 after surgery. The animals were fed the individual experimental diets for a period of 12 days while digesta were collected twice a day quantitatively during the final 5 days of this period. Precaecal digestibility for thiamin from all tested foods and feedstuffs was within a range from 73% to 94% with the highest values from boiled soybeans, boiled rice and barley, and the lowest value from steamed fish. In comparison with the animal products the plant products show on average a nearly equal precaecal digestibility for thiamin (87.3% versus 83.5%). Moreover, all tested foods and feedstuffs exhibit a relatively good intestinal availability of thiamin.

Animal Feed↗
PubMed1999

The Marks Asthma Quality of Life Questionnaire: further validation and examination of responsiveness to change.

We performed analyses to examine the structure, validity, and responsiveness to change of the Marks Asthma Quality of Life Questionnaire (AQLQ), originally validated in Australia in a self-administered format, among 539 U.S. subjects with asthma. Subjects were interviewed twice by telephone over an 18-month period. Based on factor analyses, the subscale structure of the AQLQ was modified slightly to eliminate item overlap among subscale scores. Cross-sectionally, total AQLQ scores were significantly correlated in expected directions with baseline asthma severity scores (r = 0.58), SF-36 physical (r = -0.66) and mental (r = -0.40) health status scores, and pulmonary function (FEV1% predicted, r = -0.14). Longitudinally, changes in AQLQ total and subscale scores were significantly (P<0.01) associated with changes in asthma severity and both physical and mental status. The AQLQ, administered by telephone, appears to be useful for assessing changes in the impact of adult asthma.

Adult↗
PubMed1999

[Visceral resorption of intra-abdominal insufflated carbon dioxide in swine].

OBJECTIVES: Total intraperitoneal carbon dioxide (CO2) resorption from CO2-pneumoperitoneum increases in relation to intraabdominal pressure (IAP) up to an upper limit of 10 to 15 mmHg. The purpose of this prospective study was to evaluate the visceral fraction of CO2 resorption in comparison to total intraperitoneal CO2 resorption in pigs to address possible reasons for this upper limit. METHODS: 16 pigs were chronically instrumented. Via midline laparotomy, a transit-time ultrasound flow probe was placed around the portal vein for continuous recording of the portal venous blood flow and a catheter was inserted into the portal vein via lienal vein. After complete recovery (7-10 days), animals were anesthetized with propofol and fentanyl and a pulmonary artery, a hepatic venous, an arterial, and an intraabdominal insufflation catheter were inserted. Mechanical ventilation (O2/air; FiO2 = 0.4) was adjusted to maintain endtidal CO2 at 34 to 36 mmHg using an Engstrøm Elvira ventilator. After an equilibration period of 3h, CO2, (n = 8) or air (n = 8) was insufflated. IAP was increased in steps of 4 mmHg and maintained constant at each respective IAP-level for 20 min. Blood gas analyses were assessed from portal venous, hepatic venous, central venous, and arterial probes at each IAP-level. Total intraperitoneal CO2 resorption was calculated from parameters derived from indirect calorimetry, the portal venous fraction from blood gas values and the portal venous blood flow following Fick's principle. Data were analyzed using Friedman's test. RESULTS: Total CO2 resorption increased continuously with rising IAP. Highest values were measured at IAP = 16 mmHg with 84 (74-93) ml/min. A further increase of IAP resulted in a significant decrease of total CO2 resorption. The visceral fraction of intraperitoneal CO2 resorption increased up to 28 (17-36) ml/min at IAP = 12 mmHg. Portal venous blood flow was also elevated or unchanged up to this IAP. At IAP = 20 mmHg or IAP = 24 mmHg portal venous blood flow decreased (79% of baseline) and in consequence portal venous calculated fraction of intraperitoneal carbon dioxide resorption decreased to 14 (8-20) ml/min. 20 min after desufflation, intraabdominal CO2 resorption was completed. With air insufflation, all parameters of CO2 balance were unchanged. DISCUSSION: The IAP dependent increase in CO2 resorption is limited due to an IAP related occlusion of the peritoneal capillaries and the limited expansion of peritoneal diffusion area. In this model, it was possible to show that visceral fraction is about one third of the total intraperitoneal carbon dioxide resorption and that this fraction depends on portal venous blood flow. Thus, a decrease in total CO2 resorption may indicate a reduction in portal venous blood flow.

Abdomen↗
PubMed1999

[Salivary cortisol as a stress parameter in piglets].

The relationship between salivary and plasma levels of total and free cortisol was monitored in 97 male piglets, aged two to four weeks, subjected to castration. Samples were taken 10 minutes before (basal value) as well as one, two, three, four and 24 hours post castration and at the same time intervals from a control group of 17 animals which did not undergo surgery. Simultaneously to blood (indwelling catheter) withdrawing saliva was collected by two cotton swabs. Cortisol levels were measured by radioimmunoassay (RIA). A highly significant increase in total, free and salivary cortisol was found within the first four hours after castration compared to the control group. The percentage increase one hour after castration above basal values was highest in free plasma cortisol (21.08 +/- 2.03 nmol/l vs. 61.26 +/- 4.16 nmol/l; 290.6%), and lowest in total plasma cortisol (177.33 +/- 9.69 nmol/l vs. 374.09 +/- 18.21 nmol/l; 211.0%), whereas salivary cortisol showed an 255.7% increase (10.46 +/- 1.03 nmol/l vs. 26.75 +/- 1.93 nmol/l). Total cortisol included 11.9-16.4% free cortisol. Salivary cortisol concentration was between 5.9% and 7.5% of the total plasma cortisol concentration. The highest correlation between total plasma cortisol and salivary cortisol occurred one hour after castration (r = 0.57; p < 0.01). The correlation between free and salivary cortisol was lowest for basal values (r = 0.27; p < 0.05), whereas correlations for the remaining time points were highly significant (0.41 < or = r < or = 0.61; p < 0.01). For the control group significant correlations were found between salivary and total plasma cortisol (0.58 < or = r < or = 0.89; p < 0.05) and between free and salivary cortisol (0.63 < or = r < or = 0.92; p < 0.05). The present work indicates that the measurement of salivary levels of cortisol reflects the concentration of this hormone in plasma samples of piglets.

Animals↗
PubMed1998

Effects of intraabdominally insufflated carbon dioxide and elevated intraabdominal pressure on splanchnic circulation: an experimental study in pigs.

BACKGROUND: Intraabdominally insufflated carbon dioxide (CO2) during laparoscopy may have a specific effect on splanchnic circulation that may be unrelated to the effects of increased intraabdominal pressure alone. Therefore, the influences of insufflation with CO2 versus air on splanchnic circulation were compared. METHODS: Pigs were chronically instrumented for continuous recording of mesenteric artery, portal venous, inferior vena cava, and pulmonary arterial blood flow and portal venous pressure. After induction of anesthesia, CO2 or air was insufflated in 14 and 10 pigs, respectively. With the pigs in the supine position, intraabdominal pressure was increased in steps of 4 mmHg up to 24 mmHg by graded gas insufflation. RESULTS: During air insufflation, mesenteric artery vascular resistance was unchanged, whereas mesenteric arterial blood flow decreased with increasing intraabdominal pressure. Shortly after CO2 insufflation to an intraabdominal pressure of 4 mmHg, mean arterial pressure, mesenteric arterial blood flow, and mesenteric arterial vascular resistance were increased by 21%, 12% and 9%, respectively. Subsequently, with the onset of CO2 resorption in the third minute, mean arterial pressure declined to baseline values and mesenteric arterial vascular resistance declined to 85% of baseline values, whereas mesenteric arterial blood flow continued to increase to a maximum of 24% higher than baseline values. At steady-state conditions during CO2 insufflation, mesenteric arterial blood flow was increased up to an intraabdominal pressure 16 mmHg but decreased at higher intraabdominal pressures. CONCLUSIONS: In contrast to air insufflation, intraabdominal insufflation of CO2 resulted in a moderate splanchnic hyperemia at an intraabdominal pressure < or = 12 mmHg. At higher intraabdominal pressure values, pressure-induced changes became more important than the type of gas used.

Abdomen↗