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D Krause

Publications and source records attributed to D Krause.

At least 73 records · Page 4Linked to original sources
PubMed1998

Climate-dependent genetic variation of alpha-2HS-glycoprotein.

We studied the possible effects of climatic factors on the world distribution of alleles determining alpha 2-HS-glycoprotein (AHSG) phenotypes in human populations. New data on AHSG polymorphism in certain ethnic groups of Russia are presented. All available data on the distribution of AHSG gene frequencies in the world (number of populations n = 51) were used to analyze possible correlations between AHSG*2 allele frequencies and seven climatic-geographic parameters. A strong positive correlation was found between AHSG*2 allele frequency and geographic latitude of territories inhabited by the study populations (r = 0.814). The dependence of the AHSG*2 allele distribution in the world on the intensity of ultraviolet radiation (400-315 nm) was estimated at r = -0.826. Such climatic characteristics as the total amount of insolation and the average annual temperature proved to make equal contributions to variation in AHSG*2 allele frequency (r = -0.683 and -0.658, respectively). A computer cartographic model of the AHSG*2 allele distribution in the Old World populations of the Northern Hemisphere was constructed.

Alleles↗
PubMed1998

[Subcutaneous trochanteric bursitis: an unrecognized cause of peritrochanteric pain revealed by imaging].

We present four cases of subcutanea trochanterica bursitis (one involving both sides). The bursitis was acute and inflammatory in two cases, chronic and microtraumatic in one, asymptomatic in one and septic in the last case. The acutely inflamed bursa may contain a blood effusion increasing the pain. CT and MRI provide distinctive images for the diagnosis of these particular types of periarticular diseases.

Acute Disease↗
PubMed1997

Multilineage gene expression precedes commitment in the hemopoietic system.

We have tested the hypothesis that multipotential hemopoietic stem and progenitor cells prime several different lineage-affiliated programs of gene activity prior to unilineage commitment and differentiation. Using single cell RT-PCR we show that erythroid (beta-globin) and myeloid (myeloperoxidase) gene expression programs can be initiated by the same cell prior to exclusive commitment to the erythroid or granulocytic lineages. Furthermore, the multipotential state is characterized by the coexpression of several lineage-affiliated cytokine receptors. These data support a model of hemopoietic lineage specification in which unilineage commitment is prefaced by a "promiscuous" phase of multilineage locus activation.

Animals↗
PubMed1997

Role of modulation on the effect of microwaves on ornithine decarboxylase activity in L929 cells.

The effect of 835 MHz microwaves on the activity of ornithine decarboxylase (ODC) in L929 murine cell was investigated at an SAR of approximately 2.5 W/kg. The results depended upon the type of modulation employed. AM frequencies of 16 Hz and 60 Hz produced a transient increase in ODC activity that reached a peak at 8 h of exposure and returned to control levels after 24 h of exposure. In this case, ODC was increased by a maximum of 90% relative to control levels. A 40% increase in ODC activity was also observed after 8 h of exposure with a typical signal from a TDMA digital cellular telephone operating in the middle of its transmission frequency range (approximately 840 MHz). This signal was burst modulated at 50 Hz, with approximately 30% duty cycle. By contrast, 8 h exposure with 835 MHz microwaves amplitude modulated with speech produced no significant change in ODC activity. Further investigations, with 8 h of exposure to AM microwaves, as a function of modulation frequency, revealed that the response is frequency dependent, decreasing sharply at 6 Hz an 600 Hz. Exposure with 835 MHz microwaves, frequency modulated with a 60 Hz sinusoid, yielded no significant enhancement in ODC activity for exposure times ranging between 2 and 24 h. Similarly, exposure with a typical signal from an AMPS analog cellular telephone, which uses a form of frequency modulation, produced no significant enhancement in ODC activity. Exposure with 835 MHz continuous wave microwaves produced no effects for exposure times between 2 and 24 h, except for a small but statistically significant enhancement in ODC activity after 6 h of exposure. Comparison of these results suggests that effects are much more robust when the modulation causes low-frequency periodic changes in the amplitude of the microwave carrier.

Animals↗
PubMed1997

The role of temporal sensing in bioelectromagnetic effects.

Experiments were conducted to see whether the cellular response to electromagnetic (EM) fields occurs through a detection process involving temporal sensing. L929 cells were exposed to 60 Hz magnetic fields and the enhancement of ornithine decarboxylase (ODC) activity was measured to determine cellular response to the field. In one set of experiments, the field was turned alternately off and on at intervals of 0.1 to 50 s. For these experiments, field coherence was maintained by eliminating the insertion of random time intervals upon switching. Intervals < or = 1 s produced no enhancement of ODC activity, but fields switched at intervals > or 10 s showed ODC activities that were enhanced by a factor of approximately 1.7. These data indicate that it is the interval over which field parameters (e.g., amplitude or frequency) remain constant, rather than the interval over which the field is coherent, that is critical to cellular response to an EMF. In a second set of experiments, designed to determine how long it would take for cells to detect a change in field parameters, the field was interrupted for brief intervals (25-200 ms) once each second throughout exposure. In this situation, the extent of EMF-induced ODC activity depended upon the duration of the interruption. Interruptions > or = 100 ms were detected by the cell as shown by elimination of field-induced enhancement of ODC. That two time constants (0.1 and 10 s) are involved in cellular EMF detection is consistent with the temporal sensing process associated with bacterial chemotaxis. By analogy with bacterial temporal sensing, cells would continuously sample and average an EM field over intervals of about 0.1 s (the "averaging" time), storing the averaged value in memory. The cell would compare the stored value with the current average, and respond to the EM field only when field parameters remain constant over intervals of approximately 10 s (the "memory" time).

Animals↗
PubMed1997

Bioeffects induced by exposure to microwaves are mitigated by superposition of ELF noise.

We have previously demonstrated that microwave fields, amplitude modulated (AM) by an extremely low-frequency (ELF) sine wave, can induce a nearly twofold enhancement in the activity of ornithine decarboxylase (ODC) in L929 cells at SAR levels of the order of 2.5 W/kg. Similar, although less pronounced, effects were also observed from exposure to a typical digital cellular phone test signal of the same power level, burst modulated at 50 Hz. We have also shown that ODC enhancement in L929 cells produced by exposure to ELF fields can be inhibited by superposition of ELF noise. In the present study, we explore the possibility that similar inhibition techniques can be used to suppress the microwave response. We concurrently exposed L929 cells to 60 Hz AM microwave fields or a 50 Hz burst-modulated DAMPS (Digital Advanced Mobile Phone System) digital cellular phone field at levels known to produce ODC enhancement, together with band-limited 30-100 Hz ELF noise with root mean square amplitude of up to 10 microT. All exposures were carried out for 8 h, which was previously found to yield the peak microwave response. In both cases, the ODC enhancement was found to decrease exponentially as a function of the noise root mean square amplitude. With 60 Hz AM microwaves, complete inhibition was obtained with noise levels at or above 2 microT. With the DAMPS digital cellular phone signal, complete inhibition occurred with noise levels at or above 5 microT. These results suggest a possible practical means to inhibit biological effects from exposure to both ELF and microwave fields.

Animals↗
PubMed1997

Mitochondrial D-loop 3' (CA)n repeat polymorphism: optimization of analysis and population data.

We report a dinucleotide repeat polymorphism in the 3' area of the mitochondrial control region. The fragments obtained using a new primer set could be reliably separated by polyacrylamide gel electrophoresis (PAGE) using nondenaturing gels. A total of five alleles [(CA)3 to (CA)7] were detected on silver-stained gels. The 90 bp product corresponds to allele 5. Samples from one African and three European populations were characterized. Significant differences could be demonstrated as to the incidence of single alleles and allele distributions in different populations. These differences were found between the three European and one African Bantu population. For specific forensic questions the mitochondrial CA repeat is well suited. Gene diversities in populations of Germany, Hungary, the Russian Federation and Cameroon were 0.36, 0.40, 0.34, 0.52, respectively.

Africa↗
PubMed1997

Percutaneous recanalization of acutely thrombosed vessels by hydrodynamic thrombectomy (Hydrolyser).

A hydrodynamic thrombectomy catheter was prospectively evaluated for the treatment of recently thrombosed vessels. A total of 52 consecutive patients (42 males and 10 females; mean age 64 +/- 15 years) presenting with acute or subacute occlusion of dialysis shunts (n = 25), peripheral bypass (n = 14) or native arteries (n = 15) were treated with the Hydrolyser (Cordis Europa NV, Roden, The Netherlands). Mean occlusion time was 4 days (range 1-17 days) and mean thrombus length 19 +/- 11 cm. The Hydrolyser was effective and fast in removing thrombus, regardless of the thrombus length. No major complications were reported. The immediate procedure success rates were 82, 100, 87 and 79 % for Brescia Cimino, dialysis shunt, native arteries and bypass grafts, respectively. Adjunctive thrombolysis (applied for persistence of residual thrombus or thrombosed distal vessels too small for hydrolytic thrombectomy) was required in 4 % of thrombotic dialysis shunts, in 20 % of native arteries and in 50 % of bypass graft occlusions. On angiographic controls, distal embolizations were reported only in native arteries (13 %) and bypasses (14 %); all were successfully treated percutaneously, except for one case treated by Fogarty balloon. Cumulative primary patency rates were respectively at 6 months 56, 62, 78 and 65 % for each indication. We conclude from this preliminary clinical study that hydrodynamic thrombectomy with a Hydrolyser is a promising technique to treat acute occlusions. This device can reduce complications as well as the time required to remove large amounts of thrombus and the use of expensive thrombolytic drugs.

Angiography↗
PubMed1997

[Arteriography of the hand. Technical aspects].

Arteriography of the hand has specific indications. Digital subtraction angiography, use of pneumatic garrot to inject Buflomedyl and to create a post ischemic hyperhemia, can give an excellent arterial and venous opacification of the hand without general anesthesia. The different stages of the arteriography are examined and argued.

Angiography, Digital Subtraction↗
PubMed1996

Comparison study of the immunogenicity and safety of 5- and 10-microgram dosages of a recombinant hepatitis B vaccine in healthy infants.

BACKGROUND: It has been suggested that lower dosages of hepatitis B vaccine may be adequate for vaccinating infants and would be less costly. OBJECTIVES: To compare the immunogenicity and safety of 5 and 10 micrograms of Engerix-B recombinant hepatitis B vaccine given to healthy infants. METHODS: A prospective randomized comparison of 5- and 10-micrograms doses of Engerix-B recombinant hepatitis B vaccine given to infants at 2, 4 and 6 months of age. Seroconversion (antihepatitis B surface antigen (anti-HBs) > or = 1 mIU/ ml) and seroprotection (anti-HBs > or = 10 mIU/ml) rates as well as geometric mean antibody titers were compared at 4, 6 and 8 months. RESULTS: A total of 190 healthy infants were screened and received the first dose of vaccine. Of these infants 153 were eligible to continue in the study. Both dosages proved to be highly immunogenic, producing high seroconversion and seroprotection rates and geometric mean anti-HBs concentrations after 3 doses. Although 10 micrograms induced significantly greater geometric mean concentrations (1641 mIU/ml compared 880 mIU/ml at 8 months of age), the seroprotection rates were identical (98.5%). CONCLUSIONS: Both dosages were well-tolerated and no serious adverse experiences were reported. However, the 5 micrograms of Engerix-B administered at 2, 4 and 6 months of age did not induce as great an anti-Hbs concentration as did 10 micrograms. Long term studies are required to determine whether using the lower dosage would sacrifice long term efficacy.

Dose-Response Relationship, Immunologic↗
PubMed1996

Comparison study of the immunogenicity and safety of 5- and 10-microgram dosages of a recombinant hepatitis B vaccine in healthy children.

OBJECTIVE: To compare the immunogenicity and safety of 5 micrograms with 10 micrograms of Engerix-B recombinant hepatitis B vaccine when given to healthy children, 2 to 6 years of age. METHODS: Randomized multicenter study of serongative children 2 to 6 years of age who received Engerix-B hepatitis B vaccine either 5 micrograms/0.25 ml or 10 micrograms/0.5 ml (the current Food and Drug Administration-approved dosage of Engerix-B in children) at 0, 1 and 6 months. Serum was obtained at 1, 3, 6 and 8 months after the first vaccine dose was given for antibody measurement. RESULTS: A total of 223 subjects were screened and received the first dose of vaccine. Of these subjects 193 continued in the study. Both dosages proved to be highly immunogenic, producing high seroconversion and seroprotection rates and geometric mean antibody to hepatitis B surface antigen concentrations after 3 doses. The geometric mean concentrations of seroconverters at Months 6 and 8 were significantly greater for the 10-micrograms group compared with the 5-micrograms group. Both dosages were well-tolerated and no serious adverse events were reported. CONCLUSIONS: There was a significant reduction in geometric mean concentrations on lowering the dosage of Engerix-B from 10 to 5 micrograms in children 2 to 6 years of age. Although a high seroprotection rate was elicited by the 5-micrograms dose, the lower antibody concentrations achieved may make this lower dosage less desirable in the long term. Further studies are required to examine the need for booster doses of vaccine with both dosing schedules.

Child↗
PubMed1996

[Surgical outcome in subtrochanteric fractures. A study over 15 years].

During the past 15 years new methods for the surgical approach to subtrochanteric fractures have been developed, e.g. the dynamic hip screw (DHS) and the gamma-nail (GN). Reviewing the results of this change in methods, we report on 102 patients after subtrochanteric fractures of the femur. We divided them into three groups according to the time of operation (1980-1984, period I; 1986-1989, period II; 1991-1993, period III). During period I, 74% of the fractures were stabilized using angle plates. During period III, more than 30% were operated on using the DHS and nearly 50% using the GN. The total hospital stay (department of surgery as well as geriatric hospital) decreased from 107.5 +/- 46.5 days to 78.9 +/- 24.3 days (P < 0.001). During period I, 86.2% of patients could be discharged home, during period III, 100%. Serious complications decreased during these 15 years. In conclusion, as observed in pertrochanteric fractures, the introduction of new operative techniques for the treatment of subtrochanteric fractures in the elderly was followed by a shortened hospital stay, a decreased complication rate and an increased rate of discharge home.

Activities of Daily Living↗
PubMed1996

[Leg embolisms: treatment via percutaneous thrombo-aspiration].

PURPOSE: Benefits of the local thrombolytic therapy in the treatment of acute peripheral arterial ischemia have been proved (13), but the place of thrombo-aspiration in this percutaneous treatment is not well defined. This study evaluates the results of thromboaspiration with or without local thrombolysis for the treatment of arterial embolism associated with a lower limb arteriopathy. METHODS: From May 1991 to May 1992, ten arterial embolisms (below the common femoral artery) associated with a lower limb arteriopathy have been treated by thromboaspiration with or without local thrombolysis. RESULTS: Nine immediate successes have been obtained. One failure has been operated on with success. On the third day, an occlusion of the popliteal artery occured and a femoroperoneal bypass was performed. But the occlusion of the bypass obligated to an amputation above the knee. This patient died one month later (hospital mortality 10%). During the follow-up (2 months), other procedures were patent. CONCLUSIONS: Thromboaspiration with or without thrombolysis is efficient for the treatment of arterial embolism associated with a lower limb arteriopathy.

Aged↗
PubMed1996

Psychosocial problems faced during absorption of Russian-speaking new immigrants into Israel: a systematic approach.

The problems faced by immigrants during the absorption process are multidimensional and require a systematic approach. According to the authors' theoretical perspective and clinical experience, two main principles determine the "facets" of absorption: search activity and self-esteem. The paper begins with a definition of search activity and its relationship to self-esteem and then discusses intrapsychic and environmental blocks to search activity and their effect on self-esteem. The paper concludes with a therapeutic approach toward restoration of search activity and self-esteem.

Acculturation↗