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Biomedical subjects

A Mayr

Publications and source records attributed to A Mayr.

At least 37 records · Page 2Linked to original sources
PubMed2000

Low platelet count and elevated serum thrombopoietin after severe trauma.

Platelet count is regularly low in patients after multiple trauma, mainly due to blood loss and dilution. Thrombopoietin (TPO) is the main regulator of the circulating platelet mass. Under several clinical conditions an inverse correlation between TPO and the circulating platelet mass was reported. Since platelets bind and internalize TPO, a platelet-dependent regulation of TPO was suggested. Thus, acute blood loss should be accompanied by elevated TPO. We measured serum TPO, platelets, interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) in 17 multiple traumatized victims. Blood was collected within 12 h after trauma as well as in the morning of days 2, 4, 6 and 9 after admission at the intensive care unit. Platelet count was low at admission and remained low until day 4. Thereafter platelets increased until day 9. TPO nearly doubled within the first 2 d, reaching its maximum on day 6. IL-6 was initially very high and steadily decreased until day 9. VEGF increased 3-fold during the 9 d. Statistically significant correlations of TPO were found with platelets and IL-6, but not with VEGF. In multiple traumatized patients low platelet count is followed by a rapid increase in serum TPO. This fits into the concept of a feedback regulation between circulating TPO and platelet mass.

Adult↗
PubMed2000

Acute respiratory failure associated with catastrophic antiphospholipid syndrome.

We present a case of multiple organ dysfunction syndrome with acute respiratory failure due to alveolar haemorrhage associated with antiphospholipid antibodies in a 42-year-old woman with a medical history of antinuclear antibody-negative systemic lupus erythematosus and antiphospholipid syndrome. Severe respiratory failure, circulatory shock and acute renal failure necessitated artificial ventilation, inotropic and vasopressor therapy, and continuous venovenous haemofiltration. A tentative diagnosis of haemorrhagic lupus pneumonitis or pulmonary manifestation of antiphospholipid syndrome was made. Lupus anticoagulant, IgG anticardiolipin and anti-beta2-glycoprotein I antibodies were positive. High-dose glucocorticoid, anticoagulation with heparin, plasmapheresis and cyclophosphamide improved her clinical condition. Despite this, the patient died several days later of spontaneous intracranial haemorrhage. This case illustrates the uncommon manifestation of acute respiratory failure associated with antiphospholipid syndrome.

Acute Disease↗
PubMed2000

Adaptation of reptilian paramyxovirus to mammalian cells (Vero cells).

The reptilian paramyxovirus GOV was successfully adapted to Vero cells in 80 passages at 30 degrees C. The virus replicated with HA titres of 1:64 and 10(7.5) TCID50/ml in the heterologous host cells forming syncytia, giant cells and cytoplasmic inclusion bodies. After 80 passages GOV was identified by immunofluorescence, by immune electron microscopy and by PCR. Sequencing of RT-PCR products of GOV after 80 passages did not reveal changes in the nucleotide sequence of the partial L-gene of GOV.

Animals↗
PubMed2000

Individual speed dependency of forelimb lameness in trotting horses.

Using a system for motion analysis, linear correlation of speed and forelimb lameness was measured in 16 horses trotting on a treadmill at a minimum of three different trotting speeds. Forelimb lameness was determined as asymmetry of vertical head motion during left and right forelimb stance. In seven horses with a moderate forelimb lameness (head motion asymmetry >40%), lameness increased significantly with trotting speed. In a further seven horses with mild or subclinical forelimb lameness (head motion asymmetry <40%) and in two horses with a moderate forelimb lameness, no significant correlation between speed and motion asymmetry was found. The results indicate that moderate forelimb lameness measured as head motion asymmetry depends on the speed at which the measurements are taken. If head motion asymmetry is measured at two trotting speeds, it can be standardized to any speed within the trotting speed range.

Animals↗
PubMed2000

[Infrared and Raman spectra studies on isomultinuclear organometallic carbyne compounds].

The infrared and Raman spectra of five isomultinuclear organometallic carbyne compounds were studied. The results show that the introduction of N atom from TMEDA or P atom from DPPE to W atom (both N and P are strong sigma-donor and weak pi-acceptor) will decrease the bonding intensity of W identical to C. The pressure tunning IR and Raman spectra of compound III indicate the presence of pressure-induced phase-transition near 20 kbar in it. There are two effects on the nu (W identical to C) of this compound with increasing pressure: the normal increasing the nu (W identical to C) wavenumber due to the shorting W identical to C bond and increasing the W-CO pi backbonding to decrease the nu (W identical to C) wavenumber.

Carbamates↗
PubMed1999

[Intestinal ischemic reperfusion syndrome: pathophysiology, clinical significance, therapy].

Gut ischemia-reperfusion injury is a serious condition in intensive care patients. Activation of immune cells within the huge endothelial surface area of gut microcirculation may initiate a systemic inflammatory response with secondary injury to distant organs. Translocation of bacteria and toxins through a leaky gut mucosa may amplify or perpetuate systemic inflammation, leading to multiple organ dysfunction syndrome and death in critically ill patients. Gut ischemia promotes regional production of inflammatory mediators, expression of cell adhesion molecules on endothelial and immune cell surfaces and increases the procoagulatory properties of vascular endothelial cells. During reperfusion, gut injury may be amplified by increased production of oxygen radicals and exhaustion of endogenous antioxidant defence mechanisms. Although several therapeutic strategies to interrupt the pathophysiology of ischemia-reperfusion have been shown to be beneficial in animal experiments, none of these interventions has gained clinical relevance. After initial hemodynamic and respiratory stabilisation of critically ill patients, strategies to prevent secondary gut injury by increasing splanchnic oxygen delivery or augment mucosal cell regeneration may be the only therapeutic options for intensive medical specialists at the present time. Early enteral nutrition and treatment with specific vasoactive drugs may reduce morbidity and costs of treatment in certain critically ill patients. However definitive evidence of a reduction in mortality with these therapies has still not be provided.

Animals↗
PubMed1999

Poor response to activated protein C as a prominent risk predictor of advanced atherosclerosis and arterial disease.

BACKGROUND: The potential role of activated protein C (APC) resistance in arterial thrombosis and disease is a matter of ongoing controversy. METHODS AND RESULTS: In the present population-based survey, a random sample of 826 men and women underwent high-resolution duplex ultrasound scanning of the carotid and femoral arteries. Response to APC was expressed in APC ratios. Subjects were tested for the factor V Leiden mutation. The risk of carotid stenosis increased gradually with decreasing response to APC (adjusted OR [95% CI] for a 1-U decrease of response to APC, 1.6 [1. 2 to 2.2]), as did the risk of femoral artery stenosis (1.7 [1.3 to 2.3]) and prevalent cardiovascular disease (1.4 [1.1 to 2.0]). The association between low APC ratio and atherosclerotic vascular disease applied equally to subjects with the factor V Leiden mutation and those without. Our study identified various nongenetic determinants of poor response to APC in the general population, including behavioral, hormonal, and environmental factors. CONCLUSIONS: The present study revealed an independent and gradual association between low response to APC and both advanced atherosclerosis (stenosis) and arterial disease. Resistance to APC due to factor V Leiden mutation was only one facet of this relationship.

Adult↗
PubMed1999

Successful treatment of severe myocardial failure after postpartum haemorrhage with the use of an intra-aortic balloon pump.

We report a 29-year-old primigravid who developed cardiac failure following postpartum haemorrhage unresponsive to volume resuscitation and therapy with catecholamines and phosphodiesterase-inhibitors. Transoesophageal echocardiography (TEE) demonstrated left atrial and ventricular dilatation and global left ventricular hypokinesis. No elevation of serum MB-isoenzyme fraction was detected and other organ functions remained stable. Although emergency cardiac transplantation was considered in the presented patient, the institution of intra-aortic counterpulsation was decided on as a first treatment option. Intra-aortic balloon counter-pulsation rapidly improved cardiac function and led to weaning from pharmacological cardiac support within a few days. Mechanical circulatory assist devices can be life-saving in postpartum-haemorrhage-associated cardiac failure.

Adult↗
PubMed1999

Angiotropic large B-cell lymphoma misdiagnosed as urosepsis with multiple organ dysfunction syndrome.

A 53-year-old woman with a history of cervical carcinoma 14 years ago, treated with hysterectomy and radiation therapy, was admitted to the intensive care unit with severe SIRS (systemic inflammatory response syndrome) progressing to shock, multiple organ failure and death within 5 d. Bilateral hydronephrosis diagnosed by sonography and an enlarged left kidney with suspected abscesses verified in a CT-scan suggested the diagnosis of urosepsis. However, multiple microbiological examinations remained sterile. Despite surgical treatment and aggressive intensive care, she died in unresponsive shock. Pathohistologically, an angiotropic large B-cell lymphoma, a rare diffuse intravascular neoplasm of lymphoid origin, was diagnosed. The patient's history of abdominal radiation therapy 14 years earlier as well as multiple negative microbiological specimens in a patient with suspected urosepsis should have initiated the search for a non-infectious cause of the disease.

Abscess↗
PubMed1999

Replication of reptilian paramyxovirus in avian host systems.

The reptilian paramyxovirus GOV replicated in chicken embryo fibroblasts, in embryonated chicken eggs and in explanted chorio-allantoic membrane with titres of up to 10(8.2) TCID50/ml at 28 degrees C. The virus did not multiply above 30 degrees C. GOV re-isolated from the avian host systems was identified by immunofluorescence and by immunogold-electron microscopy.

Allantois↗
PubMed1999

[Historical review of smallpox, the eradication of smallpox and the attenuated smallpox MVA vaccine].

After the WHO had declared smallpox to be eradicated in 1980, smallpox vaccination ceased to be carried out in humans all over the world. The cutaneous inoculations carried out with live vaccines based on the vaccinia virus from 1798 onwards protected both the global population and, indirectly, the animals living with humans against orthopox infections in general. A large percentage of humans and animals no longer enjoy this protection. Idiopathic orthopox in animals (reservoir possibly rats and mice) are thus experiencing a renaissance, posing a threat to humans and animals. The paper provides an historical retrospective of smallpox epidemics in humankind, their course of development and methods employed to combat this disease, commencing long before the birth of Christ with primitive attempts in China and India and from the end of the 18th century with increasingly enhanced methods, most recently with worldwide smallpox vaccination programmes using live vaccinia vaccines. Smallpox vaccination was always accompanied by a variety of complications, especially postvaccinal encephalitis. The MVA strain was developed to reduce or prevent such adverse effects. MVA has meanwhile proved its worth both as a parenteral vaccine against orthopox infections in humans and animals and as a vector for insertion of foreign genes. The history of smallpox, the fight against this disease and the development of MVA are documented with the help of figures and tables.

Animals↗
PubMed1998

Speed dependency of motion pattern consistency.

Treadmills are widely used in equine motion analysis. For the evaluation of the trot of a horse, a trotting speed with low variation between motion cycles is necessary to make the measurements reproducible. The aim of this study is to show how an individual 'optimum' trotting speed for lameness quantification can be determined. In this study, the stability of a horse's gait pattern was evaluated by calculating the standard deviation (S.D.) of motion-cycle speed (MCS). In trot, eighteen horses were analysed at several speeds. The measurements were taken with the ExpertVision System (Motion Analysis Corporation) every 3 km h(-1) (= 0.83 m s(-1)), from the lowest to the highest individual trotting speed. At the different speeds the S.D. of MCS and the asymmetry of the vertical head motion were compared. At the speed where standard deviation was minimum, motion asymmetry was maximum. In twelve horses this optimum speed was situated in the middle of the individual trotting speed range, and in six horses the optimum speed was the maximum speed. The method presented in this study allows the determination of an optimum trotting speed and so contributes to precision and consistency of equine lameness analysis.

Animals↗
PubMed1998

[Interactions between the immune system and the psyche].

Compared to well documented studies on immunosuppression "psychologically induced immunoenhancement" is a rather neglected topic in medical literature and research, even in the new established field of psychoneuroimmunology. Starting with the premise that research questions emanating from this field and from behavioural medicine may provide critical information for understanding the phenomena of immunomodulation, evidence and illustrations of psychologically induced immunoenhancement are provided in the context of psychosocial neuroimmunomodulation. Distress-reducing interventions such as progressive relaxation training, imagery, experimentally induced short-term positive mood states and mirthful laughter enhances various aspects of immune functions, i.e., primarily the phylogenetically old paraspecific parameters. Additionally, a larger variety of emotional/psychosocial factors with potentially but yet unproved immunoenhancing effects seems to exist. In particular, enhancement of phagocytosis, NK cell and T cell response to phytohemagglutinin, decrease in the number of suppressor/cytotoxic T cells and increase in the number of circulating T helper/inducer cells in peripheral blood, and enhancement of spontaneous lymphocyte blastogenesis as well as cytokines have all been shown to be associated with the above mentioned intervention techniques.

Animals↗
PubMed1997

Loss of retinoic acid receptor beta expression in breast cancer and morphologically normal adjacent tissue but not in the normal breast tissue distant from the cancer.

Retinoids and their receptors [retinoic acid receptors (RARs) and retinoid X receptors] play an important role in maintaining the balance between proliferation and apoptosis. Recently, Deng et al. [Science (Washington DC), 274: 2057-2059, 1996] reported a loss of heterozygosity on chromosome 3p24 in breast cancer specimens and the morphologically normal appearing adjacent tissue. The 3p24 locus includes, among other genes, the region coding for RAR-beta. This study was designed to determine whether there are abnormalities in the expression of retinoid receptors in surgical specimens of patients with breast cancer. In 14 patients, transcripts of nuclear retinoid receptors were detected by in situ hybridization in formalin-fixed, paraffin-embedded specimens by means of digoxigenin-labeled riboprobes specific for RAR-alpha, -beta and -gamma. We found RAR-alpha expressed in all specimens, whereas RAR-gamma was expressed in 100% of normal breast tissue but in only 11 of 14 tumorous lesions. RAR-beta was found in all cases of normal breast tissue localized distant from the tumor, but in 13 of 14 cases it was completely absent in the tumor and the morphologically normal appearing tissue adjacent to the tumor. One possibility to explain the suppression of RAR-beta is a mutation in the promoter region. Sequencing the DNA extracted from paraffin-embedded tumor tissue of the corresponding breast cancer specimens, we were not able to detect any mutation in the retinoic acid-responsive element. Our results clearly indicate a crucial role of RAR-beta in the carcinogenesis of breast cancer.

Breast↗