A method to reduce the invasiveness of fetal catheterization in the cow

Surgical intervention in general anesthesia (GA) of the cow in late gestation is a stressful condition for both mother and fetus, potentially leading to premature delivery or fetal death. The present study hypothesized that fetal catheterization at days 246-253 (90% of gestation) is done with less physical and metabolic stress for the mother and fetus, when the surgery is performed on a standing cow and local anesthesia (LA) rather than on a recumbent cow in general anesthesia. Fetal and uterine maternal intra-vascular catheters were implanted during general anesthesia (GA, n=24) or local analgesia (LA, n=7). Blood gases and metabolite levels in the fetal calves and their mothers were measured during surgery and for 5 days post-operatively. During surgery, venous blood pH was higher (7.44 +/- 0.01 versus 7.39 +/- 0.01, P<0.05) and hemoglobin and oxygen contents lower in LA cows compared with GA cows (9.3 +/- 0.3 mg/dl versus 11.8 +/- 0.2 mg/dl, P<0.001 and 10.0 +/- 0.3 ml/dl versus 12.6 +/- 0.6 ml/dl, P<0.05). The differences between the two groups of fetuses reflected those of their dams in that LA fetuses showed lower arterial oxygen pressure (18.3 +/- 1.4 mmHg versus 24.8 +/- 1.4 mmHg, P<0.05) and hemoglobin (7.81 +/- 0.30 mg/dl versus 9.22 +/- 0.21 mg/dl P<0.01) and furthermore, they also showed higher blood glucose (2.4 +/- 0.2 mM versus 1.4 +/- 0.1 mM, P<0.01). During the 5 days post-surgery, 10 GA fetuses (42%) and 1 LA fetus (14%) died in utero. Bacterial contamination was implicated in six of the GA deaths and in the one LA death. In the dams with surviving calves, differences in hemoglobin (9.49 +/- 0.21 mg/dl versus 11.17 +/- 0.23 mg/dl P<0.001) and O2ct (10.9 +/- 0.3 ml/dl versus 12.5 +/- 0.5 ml/dl, P<0.05) were still present, and in addition, blood glucose was higher in LA versus GA cows (4.3 +/- 0.2 mM versus 3.8 +/- 0.1 mM, P<0.05). The choice of surgical method did not affect post-surgery blood chemistry in the surviving fetuses, except that the higher blood glucose in the LA fetuses at surgery tended to be maintained also post-operatively (2.0 +/- 0.2 mM versus 1.5 +/- 0.1 mM, P=0.07). The observed differences in blood chemistry parameters between the two methods of surgery and possibly in the fetal death may be explained by differences in catheterization method and the associated differences in physical and metabolic stress during and after surgery. Thus, surgery upon a standing cow in local anesthesia should be considered as an alternative to surgery in universal anesthesia for fetal catheterization in the cow in late gestation.

The dynamics of the hypothalamic-pituitary-adrenal axis during maternal deprivation

A close contact between the dam and the litter is essential for the normal development of the hypothalamic-pituitary-adrenal (HPA) axis in rats and mice. Maternal signals, as licking and feeding, have been shown to sustain the HPA axis of the pups in a hypo-responsive state. Disruption of this mother-pup interaction by 24 h of maternal deprivation activates the otherwise quiescent stress system of the neonates, resulting in an enhanced adrenal sensitivity to adrenocorticotropic hormone (ACTH) and a decreased expression of central HPA markers, such as corticotropin-releasing hormone (CRH). However, the dynamics of these central and peripheral changes over the 24h period are largely unknown. In this study, we examined the time course of some of the central and peripheral indices of HPA activity during 24 h of maternal deprivation. We measured corticosterone and ACTH in the blood as well as CRH, mineralocorticoid and glucocorticoid receptor expression in the brain. Our results demonstrate that each of the components of the HPA axis responds to maternal deprivation at different time points following removal of the mother and with a very specific time course. The main activation of the HPA axis occurred between 4 h and 8 h of maternal absence. By contrast, during the second half of the deprivation period, negativefeedback mechanisms restrained the further increase in ACTH and corticosterone release. We conclude that maternal deprivation triggers a cascade of sequential changes at the various levels of the stress system, and that measuring only one aspect of the system at one time point does not accurately reflect the dynamic alterations of the HPA axis.

Oxygen and silver clusters: transition from chemisorption to oxidation

We use the adsorption probabilities of molecular nitrogen and oxygen to study the physi- and chemisorption on small silver particles. The physisorption of nitrogen is governed by the structure of the particle surface. The sticking of oxygen additionally involves the electronic configuration of the metal cluster. At 77 K molecular oxygen sticks chemisorbed to the particles with a transfer of one electron. At temperatures above 105 K the chemisorption transforms into oxidation, invoking the dissociation of the oxygen molecule and the loss of a single oxygen atom.

No peri- and postnatal effects on calves born after transfer of in vitro produced embryos vitrified by the open pulled straw (OPS) method

The general objective of this study was to perform follow-up studies including selected peri- and postnatal characteristics on calves born after transfer of in vitro produced (IVP) embryos vitrified by the 'Open Pulled Straw' (OPS) method. An overall pregnancy rate of 16% after transfer of the OPS-vitrified IVP embryos was achieved and resulted in birth of 9 calves, with 11 AI calves serving as controls. There were no immediate or long-term effects on these calves with respect to birth weight, gestation length, perinatal mortality, growth rate, disease susceptibility and reproductive performance.

Conversion of aliphatic 2-acetoxynitriles by nitrile-hydrolysing bacteria

The enzymatic hydrolysis of the nitrile group of different 2-acetoxynitriles was investigated in order to obtain catalysts that chemoselectively hydrolyse nitriles in the presence of ester groups. The biotransformation of four 2-acetoxynitriles [2-acetoxybutenenitrile (ABN), 2-acetoxyheptanenitrile (AHN), 2-acetoxy-2-(2-furyl)acetonitrile (AFN), and 2-acetoxy-2,3,3-trimethylbutanenitrile (ATMB)] by different bacterial strains that synthesise nitrilases or nitrile hydratases was studied. ABN, AHN and AFN were converted by various microorganisms belonging to different bacterial genera (e.g. Pseudomonas or Rhodococcus) expressing either nitrilase or nitrile hydratase activities. In contrast, no metabolism of the sterically hindered substrate ATMB was observed. All wild-type strains investigated formed considerable amounts of cyanide and aldehydes from the 2-acetoxynitriles. This indicated the presence of esterases converting the 2-acetoxynitriles to 2-hydroxynitriles, which then spontaneously decomposed to the corresponding aldehydes and cyanide. In order to suppress unwanted side-reactions, biotransformations were performed with recombinant Escherichia coli strains that heterologously expressed nitrilase activities originating from Pseudomonas, Rhodococcus, or Synechocystis strains. The attempted conversion of the 2-acetoxynitriles to almost stoichiometric amounts of the corresponding 2-acetoxycarboxylic acids was finally achieved by using either a recombinant E. coli strain that highly overexpressed the nitrilase gene from the pseudomonad or the purified enzyme derived from this strain.

Fehlinterpretation von Urinanalysen durch in vivo wachsende Harnsteine

The occurrence of biochemically unaltered urinalyses in patients with severe recurrent stone formation is not a rare observation in practice. The possible reasons for that phenomenon are manifold. We show that stone growth-related urinary depletion of lithogenic constituents caused by acute growth of urinary calculi in vivo can be an important reason for the observed phenomenon. The described process which can strongly influence the urinary composition occurs in any stone-bearing patient. Thus, it is strongly recommended that stone-related alterations be taken into account when interpreting the urinalyses of these patients. Based on simplified model assumptions, the extent of the expected chemical depletion effect can be calculated for any stone patient's urine sample. In two easy-to-use nomograms, we have combined the key parameters which govern the process, allowing the user a fast and easy estimation.

LMO2-associated clonal T cell proliferation in two patients after gene therapy for SCID-X1

We have previously shown correction of X-linked severe combined immunodeficiency [SCID-X1, also known as gamma chain (gamma(c)) deficiency] in 9 out of 10 patients by retrovirus-mediated gamma(c) gene transfer into autologous CD34 bone marrow cells. However, almost 3 years after gene therapy, uncontrolled exponential clonal proliferation of mature T cells (with gammadelta+ or alphabeta+ T cell receptors) has occurred in the two youngest patients. Both patients' clones showed retrovirus vector integration in proximity to the LMO2 proto-oncogene promoter, leading to aberrant transcription and expression of LMO2. Thus, retrovirus vector insertion can trigger deregulated premalignant cell proliferation with unexpected frequency, most likely driven by retrovirus enhancer activity on the LMO2 gene promoter.

Activities of Proteolytic Lysosomal Enzymes in Blood and Liver of Growing Cattle

Abstract. The activities of proteolytic lysosomal enzymes were investigated in serum, leucocytes, liver and muscle of German-Holstein heifers. Altogether there were 119 investigations: 19 9 months, 80 12 months and 20 16 months old female young cattle. Lysosomal enzymes in leucocytes were proven inappropriate for investigation because of very high variation coefficients. The enzymes investigated in serum, liver and muscle only had variation coefficients ranging from 20 to 40% in most cases. The closest connection between activities of individual enzymes was observed in the liver where activities, except for that of lysosomale esterase (EL), were highly correlated with each other. High correlations were calculated between 9 and 16 months old heifers.

[Prevention, screening and therapy of thyroid diseases and their cost-effectiveness]

Cost-effectiveness analyses focused on benign thyroid diseases are under-represented in the literature. The calculation of costs per additionally gained life year is difficult: The benefit of prevention is shifted into the distant future. The influence of an untreated subclinical thyroid disease on life expectancy can only be demonstrated by a long-term follow-up and by epidemiological databases. Iodine supplementation and programs for the prevention of tobacco smoking (primary prevention) are very cost-effective. Smoking increases the risk both of multinodular goiter and of Graves' disease. Screening programs (secondary prevention) are discussed for the laboratory parameters thyrotropin (TSH), calcium and calcitonin. TSH testing seems to be very cost-effective for epidemiological considerations in a certain lifespan (newborn, pregnancy, postpartal, older persons, hospitalisation due to acute diseases) and in persons with previously elevated TPO-antibodies or TSH-values >2 mU/l, but dedicated cost-effectiveness analyses are lacking. On the other hand, the cost-effectiveness of a routine TSH testing beyond the age of 35 years has been shown by a high-quality decision analysis. Therapeutic strategies (tertiary prevention) aim at the avoidance of complications (atrial fibrillation, myocardial infarction, death for cardiac reasons) and of iatrogenic complications. Examples of a tertiary prevention are: firstly the definitive therapy of Graves' disease in patients who have an increased risk of relapse after antithyroid drugs (ATD), secondly the radioiodine therapy for subclinical hyperthyroidism and the radioiodine therapy of large goiters in older patients or in patients suffering from a relevant comorbidity. Cost-effectiveness analyses for different therapeutic strategies of Graves' disease were published using a lifelong time-horizon. The ablative radioiodine dose-regime is cost-effective as a first line therapy if the risk of relapse after ATD exceeds 60%.

The process of metastasisation for breast cancer

To investigate the process of metastasis, primary clinical data and disease events such as metastases, local recurrence and survival (median follow-up 9.4 years) from the Munich Cancer Registry from 1978 to 1996 were analysed. Since metastases, even from small tumours, may be initiated before the diagnosis of the primary tumour, the growth of the primary tumour and metastasisation may be two autonomous processes. In our data, survival following metastases was almost unrelated to primary tumour size. However, the number of M1 cases and the time to metastasisation depended on the tumour diameter at diagnosis. The time from initiation of metastases to its diagnosis was estimated as 5.8 years. The growth of metastases was almost homogeneous. However, the growth time following metastasisation-depending on the metastases-free time, receptor status and histological grade-only varied by approximately a factor of 2. Local recurrence, above all, was an indicator of metastases. Furthermore, local recurrence may also have the potential to metastasise. Excess mortality due to local recurrence was estimated up to 9.3 years after diagnosis. Our hypothesised metastases model illustrates the importance of early detection, the concept of breast-conserving therapy and additional metastases from local recurrence. It highlights the benefits of optimal local therapy of the primary tumour and the limitations of systemic therapy. It also questions the use of axilla dissection and lymph node irradiation. Its generalisation to solid tumours may help to clarify many of the current controversial debates.

Regulation of the developing hypothalamic-pituitary-adrenal axis in corticotropin releasing hormone receptor 1-deficient mice

During postnatal development, mice undergo a so-called stress hyporesponsive period, which is characterized by low basal corticosterone levels and the inability of mild stressors to induce a corticosterone response. The stress hyporesponsiveness is in part regulated by maternal factors. Twenty-four hours of deprivation results in an activation of basal and stress-induced corticosterone and a down-regulation of corticotropin releasing hormone (CRH), mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) expression in the brain. It has been hypothesized that the CRH receptor 1 (CRHr1) may play an important regulatory role during development by mediating the effects of maternal deprivation. Using CRHr1-deficient mice we examined the role of this receptor on the maternal deprivation effects and in regulating the expression of hypothalamic-pituitary-adrenal axis-related genes. We could demonstrate that the CRHr1 is essential for the activation of the corticosterone response following maternal deprivation, most likely due to the lack of the receptor in the pituitary. Furthermore, we could show that the CRHr1 is regulating the expression of CRH and MRs. In contrast, effects of maternal deprivation during postnatal development on GRs are not mediated by this receptor.

[Thin-walled apical ventricular aneurysm associated with hypertrophic obstructive cardiomyopathy]

HISTORY AND ADMISSION FINDINGS

A 73-year-old patient presented for routine follow-up examination for pre-diagnosed hypertrophic obstructive cardiomyopathy (HOCM). The patient's history included arterial hypertension and dyspnea on exertion.

INTERVENTIONS

Echocardiography revealed a large apical aneurysm, which had vastly increased in size over the past six months. Further evaluation by cardiac magnetic resonance (NMR) imaging confirmed the aneurysm and demonstrated a wall thickness of no more than 2 mm.

TREATMENT AND COURSE

Due to the rapid increase in size in addition to the extremely thin wall diameter the risk of spontaneous rupture was considered high and the patient was referred to surgical therapy. Echocardiographic and NMR-findings were confirmed intraoperatively. The aneurysm was resected and the postoperative progress was uneventful.

CONCLUSION

Aneurysms of the apical left ventricle can result from an underlying HOCM. In case of rapid increase of the aneurysm, aneurysmectomy should be performed.