Controlled trial of intravenous immune globulin in recent-onset dilated cardiomyopathy

BACKGROUND

This prospective placebo-controlled trial was designed to determine whether intravenous immune globulin (IVIG) improves left ventricular ejection fraction (LVEF) in adults with recent onset of idiopathic dilated cardiomyopathy or myocarditis.

METHODS AND RESULTS

Sixty-two patients (37 men, 25 women; mean age +/-SD 43.0+/-12.3 years) with recent onset (</=6 months of symptoms) of dilated cardiomyopathy and LVEF </=0.40 were randomized to 2 g/kg IVIG or placebo. All underwent an endomyocardial biopsy before randomization, which revealed cellular inflammation in 16%. The primary outcome was change in LVEF at 6 and 12 months after randomiz. Overall, LVEF improved from 0.25+/-0.08 to 0.41+/-0.17 at 6 months (P<0.001) and 0.42+/-0.14 (P<0.001 versus baseline) at 12 months. The increase was virtually identical in patients receiving IVIG and those given placebo (6 months: IVIG 0.14+/-0.12, placebo 0.14+/-0.14; 12 months: IVIG 0.16+/-0.12, placebo 0.15+/-0.16). Overall, 31 (56%) of 55 patients at 1 year had an increase in LVEF >/=0.10 from study entry, and 20 (36%) of 56 normalized their ejection fraction (>/=0.50). The transplant-free survival rate was 92% at 1 year and 88% at 2 years.

CONCLUSIONS

These results suggest that for patients with recent-onset dilated cardiomyopathy, IVIG does not augment the improvement in LVEF. However, in this overall cohort, LVEF improved significantly during follow-up, and the short-term prognosis remains favorable.

Targeted disruption of the acid alpha-glucosidase gene in mice causes an illness with critical features of both infantile and adult human glycogen storage disease type II

We have used gene targeting to create a mouse model of glycogen storage disease type II, a disease in which distinct clinical phenotypes present at different ages. As in the severe human infantile disease (Pompe Syndrome), mice homozygous for disruption of the acid alpha-glucosidase gene (6(neo)/6(neo)) lack enzyme activity and begin to accumulate glycogen in cardiac and skeletal muscle lysosomes by 3 weeks of age, with a progressive increase thereafter. By 3.5 weeks of age, these mice have markedly reduced mobility and strength. They grow normally, however, reach adulthood, remain fertile, and, as in the human adult disease, older mice accumulate glycogen in the diaphragm. By 8-9 months of age animals develop obvious muscle wasting and a weak, waddling gait. This model, therefore, recapitulates critical features of both the infantile and the adult forms of the disease at a pace suitable for the evaluation of enzyme or gene replacement. In contrast, in a second model, mutant mice with deletion of exon 6 (Delta6/Delta6), like the recently published acid alpha-glucosidase knockout with disruption of exon 13 (Bijvoet, A. G., van de Kamp, E. H., Kroos, M., Ding, J. H., Yang, B. Z., Visser, P., Bakker, C. E., Verbeet, M. P., Oostra, B. A., Reuser, A. J. J., and van der Ploeg, A. T. (1998) Hum. Mol. Genet. 7, 53-62), have unimpaired strength and mobility (up to 6.5 months of age) despite indistinguishable biochemical and pathological changes. The genetic background of the mouse strains appears to contribute to the differences among the three models.

Morbidity of harvesting of bone grafts from the iliac crest for preprosthetic augmentation procedures: A prospective study

It has been the aim of the present prospective clinical study to assess the morbidity following the harvest of bone from the anterior and posterior ilium in elective preprosthetic augmentations. Fifty consecutive healthy patients (30 female, 20 male, mean age 52.5+/-9.3 years, range 31 years to 65 years) underwent augmentations of implant sites by iliac crest bone grafts. The bone harvest was carried out in 25 cases from the anterior and in 25 cases from the posterior ilium. The superficial sensory function of the skin was determined quantitatively preoperatively, 7 and 30 days after surgery with the 'Pain and Thermal Sensitivity' Test (PATH Test). On the same occasions subjective pain on a visual analogue scale (VAS) and gait disturbances were documented. In the PATH Test, for the innervation areas of the lateral femoral cutaneous nerve (LFCN) and the superior and middle cluneal nerves (SMCN) a significant impairment of the superficial sensory function could be found after 1 week and a significant tendency towards recovery after 1 month (warm stimulus(FCNpreop) 37.9+/-3.0 degrees C, warm stimulus(LFCNday7): 38.6+/-3.2 degrees C, warm stimulus(LFCNday30): 37.9+/-2.9 degrees C, P(LFCNwarmpreop/day7)=0.023,P(LFCNwarmpreop/day30) =0.886, warm stimulus(SMCNpreop): 36.1+/-2.4 degrees C, warm stimulus(SMCNday7): 36.6+/-2.3 degrees C, warm stimulus(SMCNday30): 36.3+/-4.0 degrees C,P(SMCNwarmpreop/day7) <0.0005,P(SMCNwarmpreop/day30) =0.086). Gait disturbances were seen in seven patients after anterior and in three patients after posterior bone harvest 7 days after surgery (P(gaitdisturbanceanterior/posterior)=0.123). After 1 month none of the patients of both groups showed gait disturbances any longer. The maximum subjective pain level was found on the second postoperative day in both groups. It was significantly higher for the anterior approach (VAS(anteriorday2) 7.0+/-1.5, VAS(posteriorday2) 5.5+/-1.8,P(VASanterior/posteriorday2) =0.004). At day 7 and at day 30, the pain levels did no longer differ significantly (VAS(anteriorday7) 3.7+/-1.4, VAS(posteriorday7) 3.2+/-1.6,P(VASanterior/posteriorday7) =0.165, VAS(anteriorday30) 1.4+/-0.7, VAS(posteriorday30) 1.4+/-0.8,P(VASanterior/posteriorday30) =0.724). Because of the lower morbidity of bone harvest from the posterior ilium in the early postoperative phase compared to the anterior approach it seems that it should be preferred in elective augmentation procedures.

Degradation characteristics of alpha and beta tri-calcium-phosphate (TCP) in minipigs

In seven Goettingen minipigs 3.5--4.7-ml cancellous bone defects were created in the area of the tibial head on both sides. The defects were filled with alpha-TCP or beta-TCP (tricalciumphosphate). ITI implants (Straumann, Freiburg, Germany) of 3.2 x 12-mm length were inserted into the underlying ceramic substitutes. Two additional pigs were used as control. Within the periods of observation (4, 16, 20, 28, 46, 68, and 86 weeks) fluorescent dyes were applied. Nondecalcified thin-sliced sections were examined by means of light and fluorescence microscopy. In addition microangiography and microradiography were performed. Bony regeneration occurred basally and on the sides of the defect according the angiogenetic reossification pattern. Resorption was due to a hydrolytic and cellular degradation process. After 46 weeks histomorphological evaluation showed an incomplete osseointegration of the simultaneously implanted dental implants. The bone contact surface ratio was lower than 25%. After 86 weeks 95--97% of both alpha- and beta-TCP were resorbed. Ceramic residuals stayed within the newly formed trabeculae thus resisting further degradation until remodeling occurred. Both alpha- and beta-TCP show a comparable degradation process. At the 86-week postoperative point only small residuals of the ceramic can be found. These residuals stay within the newly formed trabeculae, which show a functional orientation. In comparison control defects showed only sparse reossification. The beta-TCP material shows an accelerated degradation mode and has an optimal reactivity with the surrounding tissues. According to the results of this animal experiment both materials can be classified as bone-rebuilding materials.

ADAMTS-13, von Willebrand factor and related parameters in severe sepsis and septic shock

BACKGROUND

Insufficient control of von Willebrand factor (VWF) multimer size as a result of severely deficient ADAMTS-13 activity results in thrombotic thrombocytopenic purpura associated with microvascluar thrombosis and platelet consumption, features not seldom seen in severe sepsis and septic shock.

METHODS

ADAMTS-13 activity and VWF parameters of 40 patients with severe sepsis or septic shock were compared with those of 40 healthy controls of the same age and gender and correlated with clinical findings and sepsis outcome.

RESULTS

ADAMTS-13 activity was significantly lower in patients than in healthy controls [median 60% (range 27-160%) vs. 110% (range 63-200%); P < 0.001]. VWF parameters behaved reciprocally and both VWF ristocetin cofactor activity (RCo) and VWF antigen (VWF:Ag) were significantly (P < 0.001) higher in patients compared with controls. Neither ADAMTS-13 activity nor VWF parameters correlated with disease severity, organ dysfunction or outcome. However, a contribution of acute endothelial dysfunction to renal impairment in sepsis is suggested by the significantly higher VWF propeptide and soluble thrombomodulin levels in patients with increased creatinine values as well as by their strong positive correlations (creatinine and VWF propeptide r(s) = 0.484, P < 0.001; creatinine and soluble thrombomodulin r(s) = 0.596, P < 0.001).

CONCLUSIONS

VWF parameters are reciprocally correlated with ADAMTS-13 activity in severe sepsis and septic shock but have no prognostic value regarding outcome.

Only snake curaremimetic toxins with a fifth disulfide bond have high affinity for the neuronal alpha7 nicotinic receptor

Long chain and short chain curaremimetic toxins from snakes possess 66-74 residues with five disulfide bonds and 60-62 residues with four disulfide bonds, respectively. Despite their structural differences all of these toxins bind with high affinity to the peripheral nicotinic acetylcholine receptors (AChR). Binding experiments have now revealed that long chain toxins only, like the neuronal kappa-bungarotoxin, have a high affinity for a chimeric form of the neuronal alpha7 receptor, with Kd values ranging from about 1 to 12 nM. In contrast, all other toxins bind to the chimeric alpha7 receptor with a low affinity, with Kd values ranging between 3 and 22 microM. These results are supported by electrophysiological recordings on both the wild-type and chimeric alpha7 receptors. Amino acid sequence analyses have suggested that high affinities for the neuronal receptor are associated with the presence of the fifth disulfide at the tip of the toxin second loop. In agreement with this conclusion, we show that a long chain toxin whose fifth disulfide is reduced and then dithiopyridylated has a low affinity (Kd = 12 microM) for the neuronal alpha7 receptor, whereas it retains a high affinity (Kd = 0.35 nM) for the peripheral AChR. Thus, a long chain curaremimetic toxin having a reduced fifth disulfide bond behaves like a short chain toxin toward both the peripheral and neuronal AChR. Therefore, functional classification of toxins that bind to AChRs should probably be done by considering their activities on both peripheral and neuronal receptors.

Harvesting of bone from the iliac crest—comparison of the anterior and posterior sites

In 1998 we harvested a total of 127 bone grafts from the iliac crest of 65 male and 53 female patients aged 8-80 years. We measured the quantity of bone obtained, the operating time and the donor site morbidity of the anterior approach (n=81) compared with the posterior approach (n=46). The mean volume of bone harvested was 15 cm(3) (range: 9-25.5) of monocorticocancellous- or bicortico-cancellous bone chips or those from a trephine bur. The mean operating time for the anterior approach was 35 min (range: 22-48), for the posterior approach 40 min (range: 32-55). There were 15 complications, which were limited to those in whom the volume of bone exceeded 17 cm(3). The posterior approach caused less morbidity, notably in the form of significantly less pain and irregularity of gait. The patient has, however, to be repositioned during operation, which added to its total duration.

Biogenesis and function of peroxisomes and glycosomes

Peroxisomes of higher eukaryotes, glycosomes of kinetoplastids, and glyoxysomes of plants are related microbody organelles that perform differing metabolic functions tailored to their cellular environments. The close evolutionary relationship of these organelles is most clearly evidenced by the conservation of proteins involved in matrix protein import and biogenesis. The glycosome can be viewed as an offshoot of the peroxisomal lineage with additional metabolic functions, specifically glycolysis and purine salvage. Within the parasitic protozoa, only kinetoplastids have been conclusively demonstrated to possess glycosomes or indeed any peroxisome-like organelle. The importance of glycosomal pathways and their compartmentation emphasizes the potential of the glycosome and glycosomal proteins as drug targets.

Prophylactically-administered rectal acetaminophen does not reduce postoperative opioid requirements in infants and small children undergoing elective cleft palate repair

Rectal acetaminophen (Ac) is often administered prophylactically at anesthesia induction for postoperative pain management in small children and is thought to have an opioid-sparing effect. We assessed in this double-blinded, prospective, randomized study early opioid requirements after three doses of Ac (10, 20, and 40 mg/kg versus placebo) in 80 children (ASA physical status I, age 11.4 +/- 9.9 mo) undergoing cleft palate repair. Single Ac plasma concentrations were measured. Pain scores assessed in the postanesthesia care unit of > or = 4 of 10 resulted in the IV administration of 25 microg/kg piritramide, a popular European mu receptor agonist (lockout time, 10 min; maximum 0.125 mg/kg). There were no significant differences between groups with regard to the early postoperative pain scores and the overall cumulative IV opioid requirements. Maximal plasma concentrations achieved were only subtherapeutic (Ac 10 mg/kg: 8 microg/mL; Ac 20 mg/kg: 13 microg/mL; Ac 40 mg/kg: 21 microg/mL after 122, 122, and 121 min, respectively). We conclude that rectal Ac up to 40 mg/kg has no opioid-sparing effect, does not result in analgesic Ac plasma concentrations, and lacks proof of its efficacy in infants and small children undergoing cleft palate repair, whereas titrated IV opioid boluses produced rapid and reliable pain relief.

IMPLICATIONS

Acetaminophen is widely used prophylactically for postoperative analgesia in children and is thought to have an opioid-sparing effect. We showed that rectal acetaminophen up to 40 mg/kg administered at anesthesia induction lacked proof of efficacy, whereas IV opioid boluses resulted in reliable pain relief in children undergoing cleft palate repair.

Long-term results of distraction osteogenesis of the maxilla and midface

Since the beginning of 1998, eight patients have been treated by osteodistraction to correct hypoplasia of the maxilla and midface of various origins. Among them were five patients who were treated by high LeFort I osteotomies and insertion of subcutaneous intraoral distraction devices in the malar region. In the remaining three patients, extraoral distraction devices were applied after LeFort II and III osteotomies. Distraction osteogenesis was successful in all cases, resulting in a mean sagittal bone gain measured parallel to the skull base of 9.0 mm (range 4.5-12.0) in the group treated with intraoral distractors and a mean of 20.3 mm in the extraoral distraction group (range 15.0-25.0). All patients were kept under orthodontic supervision before, during, and after osteodistraction. Long-term cephalometric and clinical evaluation after a mean follow-up period of 24 months in the intraoral distraction group (range 22-26) and 12 months in the extraoral distraction group (range 10-14) show stable results concerning the skeletal and dental relations. Long-term follow-up is necessary.

Proinflammatory mediators chronically downregulate the formation of the endothelium-derived hyperpolarizing factor in arteries via a nitric oxide/cyclic GMP-dependent mechanism

BACKGROUND

Endothelium-dependent dilator responses mediated by NO and endothelium-derived hyperpolarizing factor (EDHF) are altered in arteriosclerosis and sepsis. The possibility that proinflammatory mediators that stimulate the expression of inducible NO synthase (NOS II) affect the generation of EDHF was examined in isolated arteries.

METHODS AND RESULTS

Under combined blockade of NOS and cyclooxygenase, EDHF-mediated relaxation elicited by several agonists was significantly attenuated in rabbit carotid and porcine coronary arteries exposed to cytokines and lipopolysaccharide. The blunted relaxation was coincident with NOS II expression and was prevented by inhibition of NOS II as well as of global protein synthesis. The NO donor CAS 1609 and 8-bromo-cGMP mimicked the proinflammatory mediator effect. In contrast, long-term blockade of endothelial NO generation increased the relaxation in carotid but not in coronary arteries. Proinflammatory mediators reduced the synthesis of EDHF assessed as hyperpolarization of vascular smooth muscle cells elicited by the effluent from bradykinin-stimulated coronary arteries. Proinflammatory mediators induced NOS II expression in cultured endothelial cells and decreased the expression of cytochrome P450 enzymes, which are the most probable candidates for the synthesis of EDHF.

CONCLUSIONS

Proinflammatory mediators inhibit the formation of EDHF in isolated arteries. This impairment is coincident with NOS II expression in the arterial wall and seems to be mediated through the induced generation of NO, which downregulates the putative EDHF-forming enzyme. Thus, a decreased formation of EDHF may contribute to the endothelial dysfunction in arteriosclerosis and sepsis.

Automatic reduction of NMR spectroscopic data for statistical and pattern recognition classification of samples

A general method of automatically reducing NMR spectra to provide numerical descriptors of samples has been developed and investigated. These descriptors can be used as input to pattern recognition or multivariate algorithms for sample classification. The methods have been tested using 600 MHz one-dimensional 1H NMR spectra of biofluids which are complex mixtures. The approach is, in principle, applicable to multidimensional and heteronuclear NMR spectra and to other types of liquid samples such as oils and foodstuffs as well as to situations such as 1H or 31P NMR in vivo and solid state NMR in drug formulation analysis. The method relies upon apportioning the information in the spectra to individual contiguous segments and allowing specified regions of the spectra to be omitted. Three approaches, based on the number of peaks, the summed peak heights and the summed peak areas respectively in each segment, have been tested. The effect of segment width and overlap and the effects of manipulation of the NMR spectra have been evaluated in terms of the classification of the samples using principal components analysis. A simple method of generating NMR based spectral descriptors for object classification is thus proposed.

STING Requires the Adaptor TRIF to Trigger Innate Immune Responses to Microbial Infection

The intracellular microbial nucleic acid sensors, TLR3 and STING, recognize pathogen molecules and signal to activate the interferon pathway. The TIR-domain containing protein TRIF is the sole adaptor of TLR3. Here, we report an essential role for TRIF in STING signaling: various activators of STING could not induce genes in the absence of TRIF. TRIF and STING interacted directly, through their carboxy-terminal domains, to promote STING dimerization, intermembrane translocation, and signaling. Herpes simplex virus (HSV), which triggers the STING signaling pathway and is controlled by it, replicated more efficiently in the absence of TRIF, and HSV-infected TRIF(-/-) mice displayed pronounced pathology. Our results indicate that defective STING signaling may be responsible for the observed genetic association between TRIF mutations and herpes simplex encephalitis in patients.

Physiological non-equivalence of the two isoforms of angiotensin-converting enzyme

The structurally related somatic and germinal isoforms of angiotensin-converting enzyme (ACE) contain the same catalytic active center and are encoded by the same gene, whose disruption causes renal atrophy, hypotension, and male sterility. The reason for the evolutionary conservation of both isozymes is an enigma, because, in vitro, they have very similar enzymatic properties. Despite the common enzymatic properties, discrete expression of both isoforms is maintained in alternate cell types. We have previously shown that sperm-specific expression of transgenic germinal ACE in Ace -/- male mice restores fertility without curing their other abnormalities (Ramaraj, P., Kessler, S. P., Colmenares, C. & Sen, G. C. (1998) J. Clin. Invest. 102, 371-378). In this report we tested the biological equivalence of somatic ACE and germinal ACE utilizing an in vivo isozymic substitution approach. Here we report that restoration of male fertility was not achieved by the transgenic expression of enzymatically active, somatic ACE in the sperm of Ace -/- mice. Therefore, the requisite physiological functions of the two tissue-specific isozymes of ACE are not interchangeable.

Inhibition of RNase L and RNA-dependent protein kinase (PKR) by sunitinib impairs antiviral innate immunity

RNase L and RNA-dependent protein kinase (PKR) are effectors of the interferon antiviral response that share homology in their pseudokinase and protein kinase domains, respectively. Sunitinib is an orally available, ATP-competitive inhibitor of VEGF and PDGF receptors used clinically to suppress angiogenesis and tumor growth. Sunitinib also impacts IRE1, an endoplasmic reticulum protein involved in the unfolded protein response that is closely related to RNase L. Here, we report that sunitinib is a potent inhibitor of both RNase L and PKR with IC(50) values of 1.4 and 0.3 μM, respectively. In addition, flavonol activators of IRE1 inhibited RNase L. Sunitinib treatment of wild type (WT) mouse embryonic fibroblasts resulted in about a 12-fold increase in encephalomyocarditis virus titers. However, sunitinib had no effect on encephalomyocarditis virus growth in cells lacking both PKR and RNase L. Furthermore, oral delivery of sunitinib in WT mice resulted in 10-fold higher viral titers in heart tissues while suppressing by about 2-fold the IFN-β levels. In contrast, sunitinib had no effect on viral titers in mice deficient in both RNase L and PKR. Also, sunitinib reduced mean survival times from 12 to 6 days in virus-infected WT mice while having no effect on survival of mice lacking both RNase L and PKR. Results indicate that sunitinib treatments prevent antiviral innate immune responses mediated by RNase L and PKR.

Inhibition of inducible nitric oxide synthase restores endothelium-dependent relaxations in proinflammatory mediator-induced blood vessels

Endothelium-dependent relaxations mediated by nitric oxide (NO) are attenuated in arteries exposed to proinflammatory mediators. Because proinflammatory mediators stimulate the expression of the inducible NO synthase (iNOS) in vascular cells, the role of iNOS-derived NO in the impaired endothelium-dependent relaxation was examined in arterial ring preparations. Exposure of rabbit carotid arteries to interleukin-1 beta (IL-1 beta; 100 U/mL for 7 hours) and porcine coronary arteries to a combination of tumor necrosis factor-alpha (1000 U/mL), interferon-gamma (500 U/mL), and lipopolysaccharide (10 micrograms/mL) for 15 hours (conditions that are associated with iNOS expression) markedly attenuated relaxations to receptor-dependent agonists, whereas those to the calcium ionophore A23187 and sodium nitroprusside were virtually unchanged. The impaired relaxation was not associated with a reduced level of the constitutive endothelial NOS (cNOS) but was accompanied by a reduced formation of biologically active NO as assessed in a bioassay system. The attenuated relaxation of carotid arteries to acetylcholine was not affected by superoxide dismutase and was neither found in arteries exposed to IL-1 beta for only 15 minutes nor in IL-1 beta-treated arteries for 7 hours followed by a 17-hour incubation period without the cytokine. Furthermore, no impaired relaxation was found in rings exposed to IL-1 beta in combination with either cycloheximide or N-alpha-tosyl-L-lysine chloromethyl ketone or pyrrolidine dithiocarbamate, treatments that prevent iNOS expression. In addition, selective inhibition of iNOS with S-methylisothiourea (10 mumol/L) completely restored acetylcholine-induced relaxations. These findings indicate that the continuous generation of NO induced by proinflammatory mediators plays a major role in the inhibition of endothelium-dependent relaxation, most likely by impairing a step in the signal transduction cascade that links activation of endothelial receptors to the calcium-calmodulin-dependent activation of NOS.

Distraction osteogenesis of the maxilla and midface using a subcutaneous device: report of four cases

The use of distraction osteogenesis in the hypoplastic maxilla and midface is still controversial. Since the beginning of 1998, 25 patients have been treated with osteodistraction techniques for various reasons. Among them were four patients who were treated by high LeFort I osteotomies and insertion of a newly developed subcutaneous distraction device in the malar region. Distraction osteogenesis was successful in all four cases resulting in a mean sagittal bone gain of 12.0 mm (range 7-14) at the level of distractor fixation. All patients were kept under orthodontic supervision during osteodistraction. The final occlusal relation was satisfactory. Cephalometric measurements after distraction showed an anterior rotational movement of the midface region. As the question of relapse and further growth is still not clear, Delaire masks are used to stabilize the surgical result after removal of the distractor. The importance of long-term follow-up is stressed.

Endoscopic and ultrasonographic evaluation of the maxillary sinus after combined sinus floor augmentation and implant insertion

OBJECTIVE

The aim of our study was a radiographic, endoscopic, and ultrasound follow-up of the maxillary sinus comparing 2 techniques of sinus floor augmentation.

STUDY DESIGN

Sonograms, radiographs (Waters' view) of the sinuses, and endoscopy served before and during surgery to evaluate the maxillary sinus. One week after the operation, ultrasound and radiograph follow-up (Waters' view) were carried out. Six months after the operation, we performed an ultrasound follow-up along with uncovering the implants. If any pathologic condition was found, we took another x-ray film of the sinuses, performed another endoscopic examination, or both.

RESULTS

In 23 of 63 patients, healing was uneventful. Waters' view revealed opacification of the maxillary sinus 1 week after surgery in 40 cases when the "window technique" was used. Sinusitis occurred 3 times, as a result of migration of bone chips in 2 patients. We lost 11 of 132 inserted implants during the healing and loading periods.

CONCLUSION

Endoscope-controlled sinus floor augmentation may lower the complication rate in a remaining height of the jaws between 4 and 8 mm. In our group of patients, we proved by endoscopic examination that migration of cancellous bone sequestra was the reason for sinusitis. In case of infected bone grafts with antral symptoms, sinoscopy allowed debridement and removal of a sequestrum.

Bispectral index and A-line AAI index as guidance for desflurane-remifentanil anaesthesia compared with a standard practice group: a multicentre study

BACKGROUND

This study was designed to investigate the impact of bispectral index (BIS) or A-line AAI index (based on middle-latency auditory evoked potential) monitoring on recovery times and drug consumption when compared with standard anaesthetic practice during desflurane-remifentanil anaesthesia.

METHODS

After having obtained approval from the institutional review board and written informed consent, 200 adult patients undergoing minor surgical procedures were randomized to receive a desflurane-remifentanil anaesthetic controlled either solely by clinical parameters or by BIS or AAI to the following target values: during maintenance of anaesthesia to a value of '50' (BIS) or '30' (AAI), 15 min before the end of surgery to '60' (BIS) or '45' (AAI). Recovery times and drug consumption were recorded by a blinded investigator.

RESULTS

Compared with standard practice, patients with BIS or AAI monitoring needed similar desflurane concentrations (standard practice 2.9 [0.5] vol%, BIS 3.3 [0.9] vol%, AAI 2.6 [0.5] vol%), and had similar recovery times (open eyes 5.6 [2.5] min, 5.9 [3.4] min, 5.0 [3.1] min; extubation 6.3 [2.4] min, 6.6 [3.5] min, 5.6 [3.0] min; stating name 7.3 [2.4] min, 7.6 [3.5] min, 7.3 [6.6] min).

CONCLUSIONS

Compared with standard anaesthetic practice BIS and AAI guided titration to the used target ranges did not result in a reduction of desflurane consumption or recovery times during minor surgery with use of remifentanil.

Pharmacokinetics of remifentanil and its major metabolite, remifentanil acid, in ICU patients with renal impairment †

BACKGROUND

The pharmacokinetics of remifentanil, an opioid analgesic metabolized by non-specific esterases, and its principal metabolite, remifentanil acid (RA), which is excreted via the kidneys, were assessed as part of an open-label safety study in intensive care unit (ICU) patients with varying degrees of renal impairment.

METHODS

Forty adult ICU patients with normal/mildly impaired renal function (creatinine clearance [CL(cr)] 62.9 (sd) 14.5 ml min(-1); n=10) or moderate/severe renal impairment (CL(cr) 14.7 (15.7) ml min(-1); n=30) were included. Remifentanil was infused for up to 72 h, at a starting rate of 6-9 microg kg(-1) h(-1) titrated to achieve a target sedation level, with additional propofol (0.5 mg kg(-1) h(-1)) if required. Intensive arterial sampling was performed for up to 72 h after infusion. Pharmacokinetic parameters obtained by simultaneous modelling of remifentanil and RA data were statistically compared between the two groups.

RESULTS

Remifentanil pharmacokinetics were not significantly affected by renal status. RA clearance in the moderate/severe group was reduced to about 25% that of the normal/mild group (41 (29) vs 176 (49) ml kg(-1) h(-1), P<0.0001). Metabolic ratio, a predictor of the ratio of RA to remifentanil concentrations at steady state, was approximately eight-fold higher in the moderate/severe group relative to the normal/mild group (116 (110) vs 15 (4), P<0.0001). Maximum RA levels approached 700 ng ml(-1) in the moderate/severe group.

CONCLUSIONS

Although RA accumulates in patients with moderate/severe renal impairment, pharmacokinetic modelling predicts that RA concentrations during a 9 microg kg(-1) h(-1) remifentanil infusion for up to 15 days would not exceed those reported in the present study, for which no associated prolongation of mu-opioid effects was observed.

A Gene Expression Signature for Relapse of Primary Wilms Tumors

Anaplastic histology and metastasis are each associated with higher relapse and mortality rates in Wilms tumor patients. However, not all anaplastic tumors relapse and some nonanaplastic tumors relapse unexpectedly. To identify more accurate early prognostic indicators, we analyzed expression of 4,900 cancer-related genes in 26 primary Wilms tumors. This analysis revealed that expression of a set of four genes predicts future relapse of primary Wilms tumors with high accuracy, independent of anaplasia. Random permutation testing of this prognostic gene expression signature yielded P = 0.003. Real-time reverse transcription-PCR analysis of the four genes in an independent primary tumor set resulted in correct prediction of future relapse with an accuracy of 92%. One of the four genes in the prognostic signature, CCAAT/enhancer binding protein beta (C/EBPB), is expressed at higher levels in both primary relapsing tumors and metastatic tumors than in primary nonrelapsing tumors. Short interfering RNA-mediated down-regulation of C/EBPB expression in WiT49, a cell line derived from a metastatic Wilms tumor, resulted in spontaneous apoptosis. These findings suggest that C/EBPB is a critical survival factor for Wilms tumor cells and that its expression contributes to the prognosis of Wilms tumor patients.

Biodegradable miniplates (LactoSorb): long-term results in infant minipigs and clinical results

Metallic plates are known for their passive intraosseous transmission in the growing skull. To avoid plate removal, resorbable material with strength comparable to that of metallic plates and predictable resorption would be desirable. This should be accomplished without causing inflammatory complications and foreign body reactions often seen with highly crystalline poly-L-lactic acid or pure polyglycolic acid implants. In an animal experiment in four young Göttingen minipigs, the resorbable poly-L-lactic acid/polyglycolic acid copolymer LactoSorb was tested previously. In addition to testing the mechanical properties, the process of degradation and sub- versus epi- or supraperiosteal application of the miniplate device LactoSorb was evaluated using a frontal cranioosteoplasty model. Furthermore, LactoSorb was used in 10 patients with craniosynostosis or craniofacial trauma. During degradation, the absorbable poly-L-lactic acid/polyglycolic acid miniplates acted like metal plates because they also displayed passive intraosseous transmission in the growing animal model. Degradation took 12 to 18 months and was not delayed by bony incorporation. Their mechanical properties proved to be sufficient in craniofacial surgery. Epiperiosteal plating prolonged the passive intraosseous transmission effect during the first 3 months after surgery. There were no major inflammatory reactions seen in the experimental and/or in the clinical study.

Effects of distraction forces and frequency of distraction on bony regeneration

The rate and frequency of distraction have a decisive influence on the regenerative process. We tested a newly developed hydraulic osteodistractor in 12 pigs, which were assigned to have continuous and intermittent osteodistraction of the mandible after osteotomy. The forces necessary to distract the mandible were recorded during intermittent distraction. These data were then used for continuous distraction of the bone. Continuous osteodistraction resulted in intramembranous regeneration of bone, whereas intermittent osteodistraction caused chondroid ossification in the regeneration of the bone. Continuous osteodistraction caused speedier regeneration, and distraction forces were lower than with intermittent distraction.

Distribution of delta opioid receptor-expressing neurons in the mouse hippocampus

Delta opioid receptors participate to the control of chronic pain and emotional responses. Recent data also identified their implication in spatial memory and drug-context associations pointing to a critical role of hippocampal delta receptors. We examined the distribution of delta receptor-expressing cells in the hippocampus using fluorescent knock-in mice that express a functional delta receptor fused at its carboxyterminus with the green fluorescent protein in place of the native receptor. Colocalization with markers for different neuronal populations was performed by immunohistochemical detection. Fine mapping in the dorsal hippocampus confirmed that delta opioid receptors are mainly present in GABAergic neurons. Indeed, they are mostly expressed in parvalbumin-immunopositive neurons both in the Ammon's horn and dentate gyrus. These receptors, therefore, most likely participate in the dynamic regulation of hippocampal activity.

Survival after curative surgical treatment for primary oral squamous cell carcinoma

The purpose of this retrospective study was to review recurrence rate and survival of patients with primary oral squamous cell carcinoma (OSCC) that have received surgical treatment and adjuvant radio-therapy with curative intent in our clinic over a 6-year period. A total of 106 patients were included. The 5-year overall survival (OS) was 41%, 5-year disease-specific survival (DSS) was 77%, 5-year disease-free survival (DFS) was 72%. DSS was significantly different between early and advanced stage, 87% and 67% respectively (p = 0.04). Recurrence significantly affected survival: OS with or without recurrence at 20 months was 24% and 87% respectively (p < 0.001). Although a guideline based approach for the treatment of OSCC might provide an advantage, more data are needed for these guidelines to be based on.