Search PubMed⌕ Search

Biomedical subjects

J Schrader

Publications and source records attributed to J Schrader.

At least 19 recordsLinked to original sources
PubMed2006

[Stress-associated hypertension in the work place: results of the STARLET project].

BACKGROUND AND OBJECTIVE: To assess the influence of work stress and initial blood pressure on the prognosis of hypertension. SUBJECTS AND METHODS: In a prospective, controlled, multicentre, observational study, ambulatory 24-hour blood pressure measurements (ABPM) of employees from different work places were recorded at the work place on working days. Recurrent ABPM were performed for up to 5 years on 3448 subjects (mean age 44.6 years) who gave consent for follow-up. Subjects with hypertension were told to consult their family doctor so that they could receive antihypertensive treatment (the angiotensin receptor blocker eprosartan, an ACE-inhibitor or a beta-blocker were recommended for initial treatment). Subjects were classified as being in mental strain (stress-positive [stress+]/ stress-negative [stress-]), using standardized questionnaires. RESULTS: Only 1242 (36.0%) of the 3448 employees (69.% males) were normotensives. Only 166 (7.5%) of the 2206 hypertensives had normal ABPMs (<135/85 mmHg) and received antihypertensive treatment at the time of inclusion into the trial. During follow-up 57.8% of patients were treated with eprosartan or ACE-inhibitors, 34.6% with beta-blockers. By the time of the final visit 80.5% of hypertensives had achieved improvement of systolic and/or diastolic blood pressures (29.1% normotensive). Patients with hypertensive ABPM at baseline had more cardiovascular events than normotensives (normotensives 3.0%; grade 1 7.8%, grade 2-3 9.8%). Hypertensive ABPMs at the last follow up or an increase in blood pressure grade were associated with higher event rates than normotensives (stable normotensives 1.8% events vs. stable hypertensives 7.9%, vs. worsening or grade 2-3: 9.1%) More hypertensives were classified as stress+ than normotensives. Persons classified as stress- (or changing to stress-) had fewer events (6.2%) than those regarded as stress+ or changing to stress+ (7.1%). Persons regarded as stable stress- had lower mean blood pressures than those who were stable stress+. Change to another stress group was associated with an increase or decrease of mean blood pressure. CONCLUSIONS: Many employed people are hypertensive at work and are not treated adequately. ABPM control and antihypertensive treatment based on eprosartan, ACE-inhibitors or beta-blockers resulted in a significant increase in the number of patients with lower blood-pressure levels and a reduction in cardiovascular events. Patients under mental strain were more likely to be hypertensive. Mental strain was associated with changes in blood pressure.

Acrylates↗
PubMed2006

The genome of black cottonwood, Populus trichocarpa (Torr. & Gray).

We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

Arabidopsis↗
PubMed2006

An aqueous-organic two-phase bioprocess for efficient production of the natural aroma chemicals 2-phenylethanol and 2-phenylethylacetate with yeast.

The natural aroma chemicals 2-phenylethanol (2-PE) and 2-phenylethylacetate (2-PEAc) are of high industrial relevance and can be produced from L-phenylalanine in a yeast-based process with growth-associated product formation. Due to product inhibition, in situ product removal is mandatory to obtain economically interesting concentrations. A fed-batch approach using polypropylene glycol 1200 as in situ extractant and the precursor in a saturated concentration led to the highest 2-PE productivity reported for a bioprocess so far. With Kluyveromyces marxianus CBS 600, 26.5 g/l 2-PE and 6.1 g/l 2-PEAc in the organic phase were obtained, corresponding to space-time yields of 0.33 and 0.08 g/l h, respectively.

Acetates↗
PubMed2005

[Hypertension and stroke: new publications in 2005].

Current studies confirm the previous European recommendations according to which the individual evaluation of the patient's risk is superior to a breakdown into general therapeutic groups. Studies on primary prevention show that patients with atrial fibrillation in particular obtain greater benefit from losartan than from atenolol, and that even a small reduction in blood pressure reduced the stroke risk. The greatest benefit was seen in those patients in whom the target pressure was achieved within a period of six months. The combination of a calcium antagonist and an ACE inhibitor prevented significantly more strokes than the combination of a beta blocker and a diuretic. In studies investigators secondary prevention a sartan was found to prevent more cardiovascular events than nitrendipine.

Antihypertensive Agents↗
PubMed2005

[Old or new antihypertensives--which are better?].

Some of the reported findings of numerous studies on the treatment of hypertension are still giving rise to heated discussions. The result is conflicting recommendations and uncertainty among care-providing physicians. Today, the substances from the group of more recent hypertensive agents (calcium antagonists, ACE-inhibitors and angiotensin 1 receptor blockers) together with the classical agents (diuretics and beta blockers) are recognized as equally justifiable as the five agents of first choice in the treatment of uncomplicated hypertension. If, however, accompanying diseases are present, the choice of primary medication depends on the respective risk (diabetes, etc.) of the individual patient. In many cases, combination treatment should be considered from the very beginning.

Adrenergic beta-Antagonists↗
PubMed2005

Novel electrochemical sensor system for monitoring metabolic activity during the growth and cultivation of prokaryotic and eukaryotic cells.

A novel amperometric sensor system is presented which directly reflects the metabolic activity of prokaryotic and eukaryotic cells during cultivation. The principle of an externally mounted sensor is current measurement using a three-electrode system. Only living cells are detected since the current signal is based on a redox mediator. Added to a culture sample in its oxidized form, the mediator is reduced by cellular metabolism and subsequently re-oxidized at the anode. The spontaneous immobilisation of the cells in the reaction vessel of the sensor by swelling dextrane polymers (Sephadex) prior to measurement is the key to a fast, consistent signal. Even metabolically less active mammalian cells produce a reliable signal within a few minutes; this may open up future applications of the electrochemical sensor in closed loop process control not only for bacterial and fungal bioprocesses, but also in cell culture technology.

Biosensing Techniques↗
PubMed2005

Overexpression of sorcin enhances cardiac contractility in vivo and in vitro.

Sorcin (SOR), an EF-hand Ca(2+)-binding protein, interacts with the sarcolemmal proteins Annexin VII and L-type Ca(2+)-channel and with the sarcoplasmic reticulum (SR) Ca(2+)-release channel (ryanodine-receptor, RYR), and has been implicated to influence the intracellular Ca(2+)-homeostasis. The present study aimed at investigating the effects of increased SOR expression on force development and relaxation in virus transfected rat hearts and isolated cardiomyocytes. We generated an adenovirus encoding the SOR coding DNA with a separate cassette for green fluorescent protein (GFP) both driven by the CMV-promoter to induce SOR-overexpression (Ad.SOR.GFP). As control served an adenovirus carrying an empty cassette with a separate cassette for GFP also driven by CMV-promoters (Ad.GFP). Cardiomyocytes of healthy male rats were isolated, transfected and cultured for 48 h with Ad.SOR.GFP as well as Ad.GFP as control. In addition, Ad.SOR.GFP was injected into coronary arteries via a catheter-based technique and rat hearts were transfected in vivo for 12 days. Echocardiography was performed to assess cardiac function at 7 and 12 days before the animals were sacrificed. A 1.7-fold increase of the SOR protein amount in cultured myocytes treated with Ad.SOR.GFP compared to Ad.GFP-transfected cells indicated a successful overexpression of SOR. Cell-contracting experiments using infected cardiomyocytes (transfection: 48 h; frequency: 0.5 Hz) exhibited a significantly higher peak force of contraction (FOC) in the SOR-overexpression group (n = 64) vs. control (n = 21) (6.8% +/- 0.2% vs. 4.3% +/- 0.1%). Beta-adrenergic stimulation with forskolin resulted in similar increases in FOC. Echocardiography of in vivo transfected rat hearts exhibited enhanced fractional shortening (65.9 +/- 5.5% vs. 79.3 +/- 2.5%) and decreased end-systolic diameters indicating enhanced cardiac contractility. Gross morphology was similar in both groups after 14 days of transfection. These results strengthen the notion that overexpression of SOR improves cardiac contractility independent of beta-adrenergic stimulation and may prove beneficial in the treatment of decreased cardiac output such as heart failure.

Adenoviridae↗
PubMed2005

Diagnosis of impaired glucose tolerance in hypertensive patients in daily clinical practice.

Many patients with hypertension suffer from impaired glucose tolerance or type 2 diabetes mellitus. Although these diagnoses are generally simple and reliable, it is more difficult to diagnose impaired glucose tolerance. As the gold standard (oral glucose tolerance test (OGTT)) is complicated to perform, a simpler alternative would be useful. The aims of the Pre-Diabetes Score study are to correlate demographic and/or laboratory parameters that are clinically simple to determine with the results of the OGTT and to determine the diagnostic significance of the combinations of parameters with regard to impaired glucose tolerance. A total of 260 patients were included in the evaluation; 39% had impaired glucose tolerance and 12% had diabetes mellitus. A combination of HbA1c of > or =6%, a venous fasting glucose of > or =110 mg/dl, an age of > or =55 years, a systolic blood pressure of > or =140 mmHg and an enlarged waist size is highly predictive of impaired glucose tolerance.

Analysis of Variance↗
PubMed2004

[The significance of arterial hypertension for the development of dementia].

Studies have shown that poorly controlled hypertension in the middle-aged patient can result in an increase in cognitive functional disorders, or dementia later in life. Silent and symptomatic ischemia accelerates this development. Early antihypertensive treatment is capable of preventing the development of dementia. It is also possible that it can improve existing cognitive disorders in hypertensive patients. Further studies are needed to throw more light on this aspect.

Age Factors↗
PubMed2004

[Recurrent hemispheric symptoms without proof of ischemia].

ANAMNESIS AND CLINICAL FINDINGS: Over the last 6 years, a 48-year-old patient recurrently experienced passing neurological left hemispheric symptoms of varying strength. Because of the patient's distinctive cardiovascular risk profile, these symptoms were diagnosed as transitory ischaemic episodes. On inquiry, the patient now reported frequent headaches in close temporal connection to the events. EXAMINATIONS: Repeated imaging of the neocranium using various techniques (CCT, cMRT, MRT-angiography) revealed no conspicuous features. Duplex sonography of the brain feeding arteries, echocardiography, EEG and 24h-ECG also gave findings within the normal range for the patient's age group. Clinical chemistry showed increased values for cholesterol and triglycerides. Incidentally, a moderate upper airway resistance syndrome was identified during polysomnography. DIAGNOSIS: Suspected migraine with aura in terms of a sporadic hemiplegic migraine. TREATMENT AND COURSE: On administration of ASS and rizatriptane, the neurological hemispheric symptoms disappeared completely over the course of a few hours. Under prophylactic treatment with metoprolol and acetazolamide over two months, no further events have been observed up to now. CONCLUSION: Recurrent, temporary neurological deficits, together with the presence of several cardiovascular risk factors, can easily be misinterpreted to be the result of an underlying cerebral ischemia. Even in cases with typical cardiovascular risk profile, a migraine with aura must be considered as one of the possible causes for hemispheric neurological symptoms.

Acetazolamide↗
PubMed2004

Applied biocatalysis for the synthesis of natural flavour compounds--current industrial processes and future prospects.

The industrial application of biocatalysis for the production of natural flavour compounds is illustrated by a discussion of the production of vanillin, gamma-decalactone, carboxylic acids, C6 aldehydes and alcohols ('green notes'), esters, and 2-phenylethanol. Modern techniques of molecular biology and process engineering, such as heterologous expression of genes, site-directed mutagenesis, whole-cell biocatalysis in biphasic systems, and cofactor regeneration for in vitro oxygenation, may result in more biocatalytic processes for the production of flavour compounds in the future.

Biotechnology↗