Stimulation of protein phosphatase activity by insulin and growth factors in 3T3 cells.

Incubation of Swiss mouse 3T3-D1 cells with physiological concentrations of insulin resulted in a rapid and transient activation of protein phosphatase activity as measured by using [32P]phosphorylase a as substrate. Activation reached a maximum level (140% of control value) within 5 min of addition and returned to control levels within 20 min. The effect of insulin was dose-dependent with half-maximal activation occurring at approximately 5 nM insulin. This activity could be completely inhibited by addition of the heat-stable protein inhibitor 2, which suggests the presence of an activated type-1 phosphatase. Similar effects on phosphatase activity were seen when epidermal growth factor and platelet-derived growth factor were tested. These results suggest that some of the intracellular effects caused by insulin and growth factors are mediated through the activation of a protein phosphatase.     

Complete excision of acoustic neurinoma. Preservation of the facial nerve and hearing

Using microtechniques, total removal of acoustic neuromas with facial nerve preservation is possible today in most cases. The next barrier of operative treatment is hearing preservation which is routinely attempted, with the help of intraoperative brainstem auditory evoked responses monitoring. The present series deals with 176 operations performed sub-occipitally in 159 patients from 1970 up to 1985. Twelve patients were operated upon 29 times. According to the W.T. Koos classification, there were 16 type II, 39 type III and 121 type IV neuromas. Ten patients died postoperatively. In seven of these, death was related to surgery, in two it was caused by respiratory failure. In the last patient unexplained sudden death occurred. 169 patients had no facial weakness preoperatively, in 158 of these the facial nerve was anatomically preserved (93.5%). Facial nerve function was judged by evaluation of function of face at least 12 months after operation. Up to 36 months after surgery, a good facial result may be expected in cases where the facial nerve was macroscopically spared at completion of removal. Functional results have been reviewed in 151 patients according to the J.W. House's International Evaluation System, with an excellent or good result in 66 (44%), fair in 65 (43%), bad or poor in 20 (13%). The anatomical preservation of the cochlear nerve could be achieved in 80 patients of the group of 169 in whom the auditory function had not been damaged by a previous operation. In fact, the auditory function preservation could be reasonably attempted in 79 patients: showing a hearing loss below 70 dB on tone audiometry, whatever may be the result of speech discrimination score. 59 patients (75%) of this later group had their auditory nerve preserved, 14 (18%) showed preserved hearing function postoperatively, 10 of these with a speech discrimination score over 50%. Two of these showed an improvement of preoperative hearing, two others showed a total recovery of hearing function after removal.     

Carbon monoxide production in ventilated premature infants weighing less than 1500 g.

Mean pulmonary excretion rate of carbon monoxide in 13 premature babies on ventilators was significantly higher (p less than 0.001) than that of 19 healthy infants born at full term. This correlated with carboxyhaemoglobin concentrations in blood, indicating that the premature infants on ventilators produced abnormally large amounts of bilirubin.     

Nationales Reanimationsregister

Within the scope of the symposium “Rescue Medicine in Germany” (held at the Reisensburg near Ulm in 2002), the need for a standardized data acquisition set for prehospital cardiac arrest patients was identified. Therefore, the working group “Emergency Medicine” of the German Society of Anesthesiology and Intensive Care Medicine (DGAI) created a nationwide data acquisition system for primary medical care in prehospital cardiac arrest patients treated with cardiopulmonary resuscitation procedures. The system is in full accordance with the “Utstein style.” Integration of this data acquisition system, for example into the “Dortmund protocol,” is providing a standardized data web base of all acquired prehospital data analyze and to compare processing and structural quality. As additional modules for this nationwide data web base system, an inhospital module “further clinical treatment” and a “long-term follow-up” module are currently in the developmental process.     

Heart rate and blood pressure variability as markers of sensory blockade with labour epidural analgesia

PURPOSE: To evaluate the correlation between the progression of somatosensory blockade and changes in autonomic outflow following the onset of labour epidural analgesia. METHODS: Twelve labouring parturients consented to participate in the study. Baseline electrocardiogram, blood pressure (BP) and respiratory rate were recorded for ten minutes. The epidural consisted of 0.125% bupivacaine with 50 microg of fentanyl (total volume 20 mL). Measurements were repeated for ten minutes after initiation of the block. The level of sensory block was measured bilaterally with loss of sensation to ice at two-minute intervals. Wavelet transform was used to obtain heart rate (HR) and BP variability every two minutes following the loading dose of epidural medication. High frequency power of HR variability was used to assess changes in parasympathetic activity. The total power of BP variability was used to assess changes in sympathetic activity. A nonparametric repeated measures ANOVA was used for the variability data, and a Spearman rank correlation test was used to evaluate the relationship between the sensory block and HR and BP variability. RESULTS: The sensory block progressed to T9 at ten minutes post-epidural and was the mirror image of the decrease in total power of BP variability. High frequency power of HR variability increased to a plateau at six minutes post-epidural. A significant correlation was found between the increase in sensory block and the observed decrease in BP variability (r = -1.000, P = 0.0028). CONCLUSION: In this study of labouring parturients, BP variability correlated with the progression of both sympathetic and somatosensory block following epidural anesthesia, while HR variability was shown to be a surrogate marker of increased parasympathetic activity.     

Aortic prosthetic ring annuloplasty: a useful adjunct to a standardized aortic valve-sparing procedure?

OBJECTIVE: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. METHODS: Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. RESULTS: Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). CONCLUSION: The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm.     

Resolution of homonymous visual field loss documented with functional magnetic resonance and diffusion tensor imaging.

A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders.