PubMed Health⌕ Search

Biomedical subjects

A Lauber

Publications and source records attributed to A Lauber.

At least 19 recordsLinked to original sources

Graft patency and clinical outcome of femorodistal arterial reconstruction in diabetic and non-diabetic patients: results of a multicentre comparative analysis.

OBJECTIVE: in diabetic patients with critical limb ischaemia (CLI) an inferior success rate following infrainguinal bypass surgery is quite often suggested. The aim of this retrospective analysis was, therefore, to evaluate the graft patency and, particularly, the clinical outcome at 1 year in diabetic compared with non-diabetic patients. MATERIAL AND METHODS: two hundred and eleven patients (diabetics 94; non-diabetics 117) with femorodistal reconstruction for CLI were studied. Groups were comparable with regard to the Fontaine classification, the distribution of vascular risk factors, graft material, distal anastomosis site, and the angiographic runoff grading. RESULTS: diabetes did not adversely affect graft function. For diabetics and non-diabetics primary cumulative patency rate at 1 year was found to be 66 and 56%, respectively (p=0.10) and a virtually identical limb salvage rate of 85 and 83% was achieved (p=0.76). With regard to healing of ischaemic foot ulcers a trend against diabetics was noted with a healing rate of 81% compared to 96% in non-diabetics at 1 year (p=0.067); gangrenous foot lesions could be equally remedied in 94% and in 87% among patients with and without diabetes (p=0.44). The survival rate of diabetics, however, was significantly lower with 78% at 1 year compared with 95% in non-diabetic patients (p=0.0004). CONCLUSIONS: our preliminary results support the view that infrainguinal bypass grafting can be safely done even in diabetics. Despite increased mortality in this group, liberal indication for reconstructive vascular surgery seems to be justified by favourable patency rates and clinical outcome in selected patients.

Aged↗

[Simultaneous surgical and technical catheter revascularization of the lower extremity].

Intraoperative balloon angioplasty was performed on 17 patients and 19 arteries undergoing a concomitant vascular reconstructive procedure during the past 24 months. All angioplasties were performed with the aid of digital substraction angiography (DSA) in the operating room. The primary purpose of intraoperative angioplasty was mainly to increase outflow (18) or inflow (1) in conjunction with a planned vascular procedure. Dilatation obviated the need of more extensive vascular reconstruction in these elderly patients.

Aged↗

Differential regulation of proenkephalin gene expression by estrogen in the ventromedial hypothalamus of male and female rats: implications for the molecular basis of a sexually differentiated behavior.

The ventrolateral aspect of the ventromedial hypothalamic nucleus (VL-VM) contains many estrogen-concentrating neurons which mediate estrogen facilitation of reproductive behavior. Previous studies have shown that estrogen treatment increases proenkephalin (PE) gene expression in neurons of the VL-VM in ovariectomized female rats, and that enkephalin peptides may stimulate lordosis behavior. To determine whether there is a sex difference in steroid hormone regulation of PE gene expression we have examined the effects of estrogen and testosterone on PE mRNA levels in male rats. Slot blot hybridization analysis of RNA isolated from the ventromedial hypothalamus indicated that estrogen treatment increased PE mRNA levels in the VL-VM of ovariectomized female rats (2.2-fold), but had no measurable effect on PE mRNA levels in gonadectomized males. Testosterone treatment of gonadectomized males also had no effect on PE gene expression. To determine whether the sex difference in estrogen-inducibility of PE gene expression is due to the developmental effects of gonadal steroids, we have investigated the effect of estrogen on PE mRNA levels in the VL-VM of neonatally androgenized female rats. Unlike the genetic male, the androgenized females responded to estrogen treatment with a female-typical increase in PE mRNA levels (1.7-fold). Further, although the androgenized rats clearly exhibited signs of defeminization, they did exhibit estrogen-facilitated lordosis behavior when tested with manual stimulation. The PE mRNA induction in estrogen-treated androgenized rats correlated well with the lordosis scores obtained by manual stimulation testing. These results indicate that estrogen regulation of PE gene expression in the VL-VM is sexually differentiated and support the hypothesis that the enkephalinergic neurons of the VL-VM are involved in the regulation of female reproductive behavior.

Animals↗

[Percutaneous transluminal coronary angioplasty: determination of left ventricular function in physical stress using intravenous digital subtraction angiocardiography].

24 patients with coronary artery disease underwent intravenous digital subtraction angiocardiography at rest and during exercise before and after percutaneous transluminal coronary angioplasty (PTCA). Before PTCA mean pulmonary artery pressure increased pathologically in 20 patients (on average from 22 +/- 4 to 40 +/- 9 mm Hg, p less than 0.001). The increase in cardiac index from 4.2 +/- 1.3 to 6.2 +/- 2.01 I X min-1 X m-2 (p less than 0.01) was achieved by an increase in heart rate from 77 +/- 13 to 119 +/- 16 min-1 (p less than 0.001) as stroke volume remained unchanged during exercise (52 +/- 14 ml X m-2, resting value: 53 +/- 13 ml X m-2). Though end-systolic volume increased from 32 +/- 11 to 41 +/- 13 ml X m-2 (p less than 0.001) and ejection fraction fell from 63 +/- 8% to 56 +/- 10% (p less than 0.005), stroke volume remained unchanged due to an enhanced diastolic filling (EDVI: 86 +/- 19 ml X m-2 at rest, 92 +/- 18 ml X m-2 during exercise, p less than 0.001). After angiographically successful PTCA in 21 of 24 patients average mean pulmonary artery pressure during exercise remained pathologically elevated (36 +/- 9 mm Hg, no significant difference from value before PTCA). It normalized in only 6 of 17 patients. On the other hand there was a marked improvement of left ventricular systolic performance. Ejection fraction during exercise (65 +/- 11%) was higher than before PTCA (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Litter deficits of socially stressed and low status hamster dams.

The effects of maternal social stress, induced by pairing pregnant females, and social status, measured by agonistic behavior within pairs, on pup development was investigated in hamsters. Using litters from untreated first pregnancies as a control, 40 dams were housed either alone or paired with another dam during their second pregnancy. Within a pair, the dam with more aggressive and fewer defensive responses than the other was considered dominant. Compared to their first unpaired litters, second litters of paired dams were smaller in number. Comparisons among second litters showed that paired dams, especially submissive dams, had fewer pups than unpaired dams. It was concluded that both maternal social stress and low status increase intrauterine mortality.

Animals↗

[Left ventricular function at rest and during exercise in patients with arterial hypertension. Studies using digital subtraction angiocardiography].

Using digital subtraction angiography, left ventricular function and pulmonary artery pressure at rest and during submaximal exercise (98 +/- 33 watts) were examined in 25 patients with systemic hypertension. All patients had normal coronary arteries and a normal left ventricular function at rest. Heart rate increased in all patients (from 82 +/- 14 to 134 +/- 20 min-1, p less than 0.001). Systolic blood pressure also increased significantly in all patients (from 153 +/- 12 to 190 +/- 14 mmHg, p less than 0.001). End-diastolic and end-systolic volumes did not change on average (89 +/- 22 and 87 +/- 19 ml/m2, 28 +/- 8 and 28 +/- 10 ml/m2, respectively), neither did stroke volume nor ejection fraction (61 +/- 18 and 59 +/- 16 ml/m2, 68 +/- 7 and 67 +/- 9%, respectively). The increase in end-systolic volumes and concomitantly the decrease in ejection fraction during exercise in 8 patients points to an impairment of left ventricular function. This effect is frequently found in ventricles with less distinct hypertrophy. Cardiac index increased in each patient (from 5.1 +/- 2.1 to 8.2 +/- 2.9 I/min/m2, p less than 0.001). This is caused by the increase in heart rate while stroke volume remains unchanged. Mean pulmonary artery pressure increased in all patients from 19 +/- 6 to 35 +/- 10 mmHg on average (p less than 0.001). A pathologic increase could be observed in 18 patients. There was no correlation to angiographic parameters of left ventricular function. The exercise test was stopped in 12 patients mainly because of dyspnea. In 11 of these patients a pathologic increase of mean pulmonary artery pressure was found. As in these patients the angiographic parameters of left ventricular function were normal, the increase in pulmonary pressure is related to an impairment of diastolic function caused by hypertrophy.

Adult↗

[Digital subtraction angiocardiography: accuracy of measuring left ventricular wall thickness and wall volume during intravenous contrast media injection].

A comparison of left ventricular wall thickness and wall volume determined by intravenous digital subtraction angiocardiography and by conventional left ventricular angiocardiography was performed by linear regression analysis: wall thickness: WDDSA = 0.90 X WDLV , Syx = +/- 0.16 cm, r = 0.74; wall volume: WVOLDSA = 0.87 X WVOLLV , Syx = +/- 48 ml, r = 0.85. Compared to the deviation and scatter of corresponding data measured from two consecutive beats in conventional left ventricular angiocardiographies , the error of determination of wall thickness and wall volume, determined by intravenous digital subtraction angiocardiography, is more pronounced. The regression analysis of wall volumes under rest and bicycle exercise evaluated by digital subtraction angiocardiography revealed a similar inaccuracy ( Syx = +/- 46 ml). This is due to faults in recognition of the inner and outer contours of left ventricular wall. Our results show that measurements of left ventricular wall thickness and wall volumes by means of intravenous digital subtraction angiocardiography can only be performed with greater deviations compared to conventional left ventricular angiocardiograms.

Angiocardiography↗

[Digital subtraction angiocardiography: accuracy of left ventricular volume determination using intravenous injection of contrast medium].

The usefulness and accuracy of intravenous digital subtraction angiography of the left ventricle was proved by comparison with conventional left ventricular angiocardiography. During heart catheterization two cineangiograms were performed in 20 patients at rest: one with direct injection of contrast medium into the left ventricle and the other with intravenous injection. The intravenous angiocardiograms were processed by a hardwired digital image-processing system designed by our own group. Image enhancement was obtained by subtracting a mask image from the contrasted image of the left ventricle. The utility of four different mask modes was examined by correlating end-diastolic and end-systolic volumes determined from conventional and intravenous digital subtraction angiocardiograms of the left ventricle respectively. Reliable quantitative results could only be achieved by obtaining mask and contrasted images from the same phase of the cardiac cycle. Using these special mask modes, the standard deviations of the residuals amounted to +/- 33 and +/- 36 ml respectively. The results show that intravenous digital subtraction angiocardiography allows a quantitative determination of left ventricular volumes at rest.

Angiocardiography↗

[Reliability of digital subtraction angiocardiography for the evaluation of left ventricular function and physical stress].

The reliability of determinations of left ventricular dimensions from digital subtraction angiocardiographies during exercise using intravenous injection of contrast material was proved in 20 patients. All angiocardiograms could be analyzed qualitatively and quantitatively only by means of the time-interval-difference (TID-) mode. Compared with other mask modes the superiority of the TID-mode results from the close temporal relationship between mask and contrasted frame. Thus, changes in position and brightness of the background structures are small, and left ventricular contours can be determined accurately despite intense respiratory movements. The intra-observer variability of determinations of end-diastolic and end-systolic volumes was +/- 12 ml (i.e. 7.5% of the mean value), corresponding inter-observer variability was +/- 24 ml (i.e. 17% of the mean value), respectively. Intra-observer deviation in determining ejection fraction was 2.8% (i.e. 4.5% of the mean value). The intra-observer variability in determining left ventricular axes was basal +/- 0.40 cm (i.e. 7% of the mean value), equatorial +/- 0.73 cm (i.e. 13% of the mean value) and apical +/- 0.34 cm (i.e. 8% of the mean value). Deviations of corresponding circumferential fiber shortening rates were basal +/- 0.22 s-1 (i.e. 14% of the mean value), equatorial +/- 0.32 s-1 (i.e. 22% of the mean value), and apical +/- 0.18 s-1 (i.e. 13% of the mean value). The results show that left ventricular dimensions can be determined accurately from intravenous angiocardiograms during exercise using digital subtraction angiocardiography.

Adult↗

[Measurement and analysis of environmental noise].

In the assessment of community noise, it is important to determine the noise conditions responsible for the disturbance. This can be done with knowledge of the operating conditions and with help of the time history of the noise over an extended period. This information must be gathered in consideration of the appropriate standards and regulations. The spectral distribution of the noise as well as its time history are measured. For noise with impulsive character or containing pure tone components, a factor is added. Psychological factors must be considered. As noise criterion, the corresponding immission limits are applied. The problems of establishing such limits and the most important noise abatements measures are discussed.

Environment↗