Superiority of the University of Wisconsin solution over simple crystalloid for extended heart preservation. A study of left ventricular pressure-volume relationship.

To compare the effects of the University of Wisconsin solution with those of an extracellular crystalloid solution, Krebs-Ringer bicarbonate, as cardiac preservation media, we studied 35 adult dogs in an isolated heart preparation. Four groups of seven hearts were preserved in University of Wisconsin solution for 6 or 12 hours or in Krebs-Ringer bicarbonate solution for 6 or 12 hours. An additional group of seven hearts with no ischemia was used for a control group. In the four preservation groups, hearts were arrested by electrolyte solution (Normosol with potassium chloride, 20 mEq/L, added, 4 degrees C), flushed with 200 ml of the preservation solution, and then stored in the same solution at 1 degree to 2 degrees C. The hearts were mounted on an isolated heart preparation equipped with a computer-controlled servo-pump system that used a mock arterial system to modulate the aortic input impedance presented to the left ventricle. Left ventricular pressure-volume loops were measured on-line for 2 hours of reperfusion with autologous warm oxygenated blood. Elastance was derived from the end-systolic pressure-volume relationship, and diastolic compliance was derived from the end-diastolic pressure-volume relationship. The total left ventricular performance was assessed by the preload recruitable stroke work area, the slope, and its x-intercept, all of which derived from the stroke work (pressure-volume area)-end-diastolic volume relationship. Extended global ischemia had more deleterious effects on the end-diastolic than the end-systolic pressure-volume relationship. In confirmation with other studies, elastance did not accurately reflect the level of ventricular contractile dysfunction because of the significant amount of diastolic dysfunction. The preservation of myocardial systolic and diastolic functions, as demonstrated by the preload recruitable stroke work area and diastolic compliance, was better in the University of Wisconsin solution groups than in the Krebs-Ringer bicarbonate solution groups after 6 and 12 hours of preservation. In addition, 6 hours of preservation with University of Wisconsin solution maintained normal systolic and diastolic functions as compared with those of the control group. Preservation with University of Wisconsin solution prevented any myocardial edema formation; by contrast, this was significantly increased after 12 hours in Krebs-Ringer bicarbonate solution. Groups preserved with University of Wisconsin solution had less reperfusion injury as evidenced by the release of coronary sinus creatine kinase during reperfusion; they also had improved oxygen use during reperfusion.(ABSTRACT TRUNCATED AT 400 WORDS)     

The therapeutic use of botulinum toxin in cervical and maxillofacial conditions: an evidence-based review.

INTRODUCTION: The role of botulinum toxin as a therapeutic agent for several conditions is expanding. We sought to determine if botulinum toxin is safe and effective in treating patients with cervical dystonia and maxillofacial conditions. Our purpose was to establish a safety and efficacy profile to determine whether or not this treatment may be used prophylactically in patients undergoing dental implant therapy. METHODS: We performed a systematic search of the literature to identify randomized clinical trials evaluating patients treated with botulinum toxin as an adjunct to dental implant therapy, maxillofacial conditions including temporomandibular disorders (TMD), and cervical dystonia. RESULTS: Four randomized controlled trials (RCTs) met our search criteria in the area of cervical dystonia and chronic facial pain. No RCTs were identified evaluating dental implant therapy. Patients with cervical dystonia exhibited significant improvements in baseline functional, pain, and global assessments compared to placebo. Adverse events were mild and transient with numbers needed to harm (NNH) ranging from 12 to 17. Patients with chronic facial pain improved significantly from baseline in terms of pain compared to placebo. Rates of adverse events were less than 1%. CONCLUSION: Botulinum toxin appears relatively safe and effective in treating cervical dystonia and chronic facial pain associated with masticatory hyperactivity. No literature exists evaluating its use in dental implantology. Randomized clinical trials are warranted to determine its safety and efficacy in dental implantology and other maxillofacial conditions such as bruxism.     

Internalization of sst2, sst3, and sst5 receptors: effects of somatostatin agonists and antagonists.

The uptake of radiolabeled somatostatin analogs by tumor cells through receptor-mediated internalization is a critical process for the in vivo targeting of tumoral somatostatin receptors. In the present study, the somatostatin receptor internalization induced by a variety of somatostatin analogs was measured with new immunocytochemical methods that allow characterization of trafficking of the somatostatin receptor subtype 2 (sst2), somatostatin receptor subtype 3 (sst3), and somatostatin receptor subtype 5 (sst5) in vitro at the protein level. METHODS: Human embryonic kidney 293 (HEK293) cells expressing the sst2, sst3, or the sst5 were used in a morphologic immunocytochemical internalization assay using specific sst2, sst3 and sst5 antibodies to qualitatively and quantitatively determine the capability of somatostatin agonists or antagonists to induce somatostatin receptor internalization. In addition, the internalization properties of a selection of these agonists have been compared and quantified in sst2-expressing CHO-K1 cells using an ELISA. RESULTS: Agonists with a high sst2-binding affinity were able to induce sst2 internalization in the HEK293 and CHO-K1 cell lines. New sst2 agonists, such as Y-DOTA-TATE, Y-DOTA-NOC, Lu-DOTA-BOC-ATE (where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; TATE is [Tyr3, Thr8]-octreotide; NOC is [1-NaI3]-octreotide; and BOC-ATE is [BzThi3, Thr8]-octreotide), iodinated sugar-containing octreotide analogs, or BIM-23244 were considerably more potent in internalizing sst2 than was DTPA-octreotide (where DTPA is diethylenetriaminepentaacetic acid). Similarly, compounds with high sst3 affinity such as KE108 were able to induce sst3 internalization. In sst2- or sst3-expressing cell lines, agonist-induced receptor internalization was efficiently abolished by sst2- or sst3-selective antagonists, respectively. Antagonists alone had no effect on sst2 or sst3 internalization. We also showed that somatostatin-28 and somatostatin-14 can induce sst5 internalization. Unexpectedly, however, potent sst5 agonists such as KE108, BIM-23244, and L-817,818 were not able to induce sst5 internalization under the same conditions. CONCLUSION: Using sensitive and reproducible immunocytochemical methods, the ability of various somatostatin analogs to induce sst2, sst3, and sst5 internalization has been qualitatively and quantitatively determined. Whereas all agonists triggered sst2 and sst3 internalization, sst5 internalization was induced by natural somatostatin peptides but not by synthetic high-affinity sst5 agonists. Such assays will be of considerable help for the future characterization of ligands foreseen for nuclear medicine applications.     

An efficient, robust and fast method for the offline detection of epileptic seizures in long-term scalp EEG recordings.

OBJECTIVE: A robust and fast algorithm for the offline detection of epileptic seizures in scalp EEG is described. It is aimed for seizure detection with high sensitivity and low number of false detections in long-term EEG data without a priori information. METHODS: To capture the characteristic electrographic changes of seizures, we developed an efficient method based on power spectral analysis techniques. The integrated power is calculated in two frequency bands for three multi-channel seizure detection montages (referenced against the average of Fz-Cz-Pz, common average, bipolar) using the same parameters for all montages and all patients taking into account an appropriate artifact rejection. RESULTS: A total of 3248 h of scalp recordings containing 148 seizures from 19 patients were examined. The averaged sensitivity was 90.9% and selectivity (false-positive errors/h, FPH) was 0.29/h of the Fz-Cz-Pz montage; the other montages yielded lower sensitivities but even better selectivity values. CONCLUSIONS: Taking into account that the method has been performed in a standardized way with fixed parameters for all patients and montages the obtained values for sensitivity are quite high while the selectivity is acceptably low. The parameters can additionally be tuned to patient specific seizures. It is assumed that this may further improve the seizure detection performance. SIGNIFICANCE: The proposed method may enhance the clinical use for the detection of seizures in scalp EEG long-term monitoring during presurgical evaluation.     

Sensitivity-encoded (SENSE) proton echo-planar spectroscopic imaging (PEPSI) in the human brain.

Magnetic resonance spectroscopic imaging (MRSI) provides spatially resolved metabolite information that is invaluable for both neuroscience studies and clinical applications. However, lengthy data acquisition times, which are a result of time-consuming phase encoding, represent a major challenge for MRSI. Fast MRSI pulse sequences that use echo-planar readout gradients, such as proton echo-planar spectroscopic imaging (PEPSI), are capable of fast spectral-spatial encoding and thus enable acceleration of image acquisition times. Combining PEPSI with recent advances in parallel MRI utilizing RF coil arrays can further accelerate MRSI data acquisition. Here we investigate the feasibility of ultrafast spectroscopic imaging at high field (3T and 4T) by combining PEPSI with sensitivity-encoded (SENSE) MRI using eight-channel head coil arrays. We show that the acquisition of single-average SENSE-PEPSI data at a short TE (15 ms) can be accelerated to 32 s or less, depending on the field strength, to obtain metabolic images of choline (Cho), creatine (Cre), N-acetyl-aspartate (NAA), and J-coupled metabolites (e.g., glutamate (Glu) and inositol (Ino)) with acceptable spectral quality and localization. The experimentally measured reductions in signal-to-noise ratio (SNR) and Cramer-Rao lower bounds (CRLBs) of metabolite resonances were well explained by both the g-factor and reduced measurement times. Thus, this technology is a promising means of reducing the scan times of 3D acquisitions and time-resolved 2D measurements.     

Current state of vitiligo therapy – evidence-based analysis of the literature

Vitiligo is a skin disease with a worldwide prevalence ranging from 0.5% to 4%. Conservative therapies include photochemotherapy, phototherapy with UVB radiation (broadband UVB 290–320 nm, narrow band UVB 311 nm), systemic steroids and pseudocatalase. Modern therapeutic options include treatment with topical immunomodulators (tacrolimus, pimecrolimus), analogues of vitamin D3, excimer laser and surgery/transplantation. Our analysis compares these therapies for vitiligo and the evidence levels supporting their effectiveness. Conclusions: The face and neck respond best to all therapeutic approaches, while the acral areas are least responsive. For generalized vitiligo, phototherapy with UVB radiation is most effective with the fewest side effects; PUVA is the second best choice.Topical corticosteroids are the preferred drugs for localized vitiligo. They may be replaced by topical immunomodulators which display comparable effectiveness and fewer side effects.The effectiveness of vitamin D analogues is controversial with limited data. Surgical therapy can be very successful, but requires an experienced surgeon and is very demanding of time and facilities, thus limiting its widespread use. L-phenylalanine therapy appears effective on the face but enjoys neither widespread use nor extensive data support. No single therapy for vitiligo can be regarded as the most effective as the success of each treatment modality depends on the type and location of vitiligo.     

Current practice patterns in pancreatic surgery: Results of a multi-institutional analysis of seven large surgical departments in germany with 1454 pancreatic head resections, 1999 to 2004 (german advanced surgical treatment study group)

Despite decreasing mortality rates, morbidity is still high after pancreatic head resection. Comparative data in the United States and Europe show a relationship between hospital volume and mortality. Treatment strategies vary frequently, partially because of the lack of evidence-based data. We performed a multi-institutional analysis in Germany evaluating current numbers, indications, techniques, and complication rates of pancreatic head resection. Questionnaires were completed by seven high-volume surgical departments regarding quantitative and qualitative aspects of pancreatic head resections in the period from 1999 to 2004 (five prospective and two retrospective institutional databases). A total of 1454 pancreatic head resections (944 for malignancy) were reported. Mean annual hospital volume ranged from 14 to 52 (10 to 43 in malignancy). Mortality was between 1.1% and 4.8%, morbidity was between 24% and 46%, and pancreatic leakage was between 9% and 20%. In malignant disease, all centers perform standard lymphadenectomy and regard arterial infiltration as a contraindication for resection. However, the rate of portal vein resection varied from 0% to 28%. No consensus is seen on the type of surgery for malignancy and chronic pancreatitis. After resection for pancreatic cancer less than one fourth of the patients receive adjuvant therapy. The results of our analysis in Germany confirm that pancreatic head resection can be performed with low mortality in specialized units. Variations in indications, operative technique, and perioperative care may demonstrate the lack of evidence-based data and/or personal and institutional experience. The low number of patients receiving adjuvant therapy after resection of pancreatic cancer suggests that more efforts must be made to establish novel adjuvant therapies under randomized study conditions. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).     

The costs of atopy and asthma in children: Assessment of direct costs and their determinants in a birth cohort

The aim of this study was to estimate costs accrued by the health care of children with asthma in comparison to children with atopic eczema and seasonal rhinitis and to investigate cost determinants. From the multicenter cohort study (MAS-90), we selected children with an asthma, atopic eczema and/or seasonal rhinitis diagnosis during the first 8 years of life, and overall 8-year health care utilization was estimated retrospectively by reviewing medical records. Asthma treatment (n = 76) incurs an average cost of US$ 627 per year, 44% due to hospital stays. Atopic eczema treatment (n = 91) cost on average US$ 219 and seasonal rhinitis (n = 69) US$ 57 per year. In asthma and atopic eczema, costs increase significantly with disease severity. Allergy diagnostics use accounts for only 1% of total costs. Costs for asthma and atopic eczema treatment are highest in those years when topical steroids are used for the first time, but decrease with every further year of steroid use. A remarkable 25% of asthmatic children with severe symptoms were not treated according to national guidelines, so that most steroid treatment was initiated during the first hospital stay. In the case of asthma, total direct costs increased until the 3rd year of the disease, and then decreased with further years of diagnosis, while steroid use continued to increase. These results indicate a 'learning effect' in the treatment of asthma and atopic eczema for each patient as well as considerable cost-saving potential by preventing severe asthma. Moreover, the importance of considering cost-driving factors and using cohort or longitudinal designs in cost-of-illness approaches is emphasized.     

Cardinal points and image–object magnification with an accommodative lens implant (1 CU)

A simple mathematical method for the determination of the cardinal points of pseudophakic eyes after implantation of an accommodative intraocular lens [posterior chamber intraocular lenses (PCIOL)] is presented. The purpose of this study was to explore the changes during pseudophakic accommodation (PAC) in (1). the positions of the cardinal points, (2). the distance of the object conjugate with the retina, and (3). the image-object magnification. These theoretical accommodation data are compared with clinical measurements. METHODS AND PATIENTS: Using biometrical measurements of the axial length, equivalent power of the cornea and the anterior chamber depth (ACD) in the non-accommodated state we used linear geometric optics for determination of the cardinal points and object distance as well as lateral magnification (the ratio of image to object size). With the measurement of ACD decrease (following pharmacological stimulation of the ciliary muscle with 2% pilocarpine eye drops) we determined the changes of the cardinal points and magnification to assess PAC amplitude from the shortening of the object distance. Calculated values of PAC amplitude were compared with the respective measured values derived from amplitude measures by accommodometer, defocusing and streak retinoscopy. We analysed the results of a prospective study on 35 eyes of 28 patients after cataract surgery (target refraction: -0.2 D) and accommodative PCIOL implantation (1 CU, Human Optics AG, Erlangen, Germany) 3 months after surgery. RESULTS: After pilocarpine eye drops, ACD (mean +/- S.D., range; median) decreased by 0.88 +/- 0.48 mm (0.51-1.91; 0.66). Distance of the in-focus object decreased from the non-accommodated state (-5.62 +/- 1.83 m, -25 to -1.1; -4.83 m) to the accommodated state (ACD decrease) (-0.81 +/- 0.21, -2.11 to -0.65; -0.79 m). For a theoretical ACD decrease of 1.0 mm (the intrinsic limitation of the PCIOL design) it was -0.59 +/- 0.28, -1.31 to -0.51; -0.63 m and resulted in an objective accommodative response of 1.49 +/- 0.16, 1.21-1.81; 1.46 D, depending on the actual geometry of the individual eye. On average, magnification as induced by PAC in contrast to that induced by adequate spectacle addition differed by only about 1%. Accommodation measured with defocusing and the accommodometer correlated significantly with the theoretical value based on IOLMaster measurement of ACD decrease (r = 0.752, p = 0.005 and r = 0.676, p = 0.02). Likewise, accommodation measured with streak retinoscopy correlated weakly with the theoretical value based on IOLMaster ACD decrease (r = 0.465, p = 0.05). CONCLUSIONS: Using geometrical optics, PAC can be derived from the biometric data of the eye and the measured ACD decrease. This approach may be an additional indicator for the accommodative response in pseudophakic patients and may allow a subdivision of the measured accommodation into true PAC and pseudoaccommodation, for example, because of increased depth of focus induced by pupillary constriction.     

Effect of a 0.5% Dilution of Propofol on Pain on Injection during Induction of Anesthesia in Children

Background: Pain on injection of propofol in children has been reported to be as high as 30-80%. The reason for the pain is assumed to be the aqueous phase of the propofol emulsion. Therefore, for the first time, this study tested the hypothesis that dilution of propofol to a 0.5% emulsion might reduce the incidence of pain during propofol injection.

Methods: The study design was prospective, monocenter, double-blind, and randomized. Sixty-four children aged 2-6 yr were scheduled to receive 0.5% or 1.0% propofol in a medium-chain-triglyceride/long-chain-triglyceride emulsion. Incidence and intensity of pain were assessed by spontaneous expressions of pain and withdrawal of the arm. In a subgroup of 21 children, serum triglyceride levels were measured before and 3 and 20 min after induction. Adverse events were recorded.

Results: Amounts of propofol required until loss of eyelash reflex were 4.40 +/- 1.01 mg/kg for 0.5% propofol and 4.31 +/- 0.86 mg/kg for 1.0% propofol. Percentages of children who showed at least one pain reaction were 23.3% in the 0.5% propofol group and 70.0% in the 1.0% propofol group (P < 0.001). Serum triglycerides were higher in the 0.5% propofol group 3 and 20 min after injection (251.7 vs. 148.8 mg/dl; P = 0.001 and 135.5 vs. 75.5 mg/dl; P = 0.03). Adverse events or complications did not occur.