Suturing methods in prolapse surgery: a biomechanical analysis.

INTRODUCTION: Pelvic organ prolapse is a common problem in urogynecological surgery. Abdominal and laparoscopic sacrocolpopexy is currently considered to be the gold standard of treatment. The main problem remains the anatomical point of fixation as well as how sutures are placed. We evaluated the biomechanical difference between an in-line ligament suture versus an orthogonal ligament suture and a single suture versus a continuous suture at the anterior longitudinal ligament in an in-vitro, sacrocolpopexy model. METHODS: Biomechanical in-vitro testing was performed on human, non-embalmed, female cadaver pelvises. An Instron test frame (tensinometer) was used for load/ displacement analysis. The average patient age was 75 years. Ligament preparation yielded 15 ligaments available for testing. Recorded parameters were the ultimate load, failure displacement, and stiffness. RESULTS: This in-vitro analysis of different suturing methods showed the difference between an orthogonal and an in-line approach to be the ultimate load. Orthogonal sutures displayed an ultimate load of 80 N while in-line suturing yielded only 57 N (p < 0.05). For the anterior longitudinal ligament, this study demonstrated that continuous suture is significantly superior to a single suture regarding failure displacement (p < 0.05). CONCLUSION: We established baseline biomechanical parameters for the sacrospinous ligament and anterior longitudinal ligament. An orthogonal suture is superior to an in-line suture in an in-vitro model. A continuous suture is superior to a single suture at the anterior longitudinal ligament. Clinical trials might be able to evaluate whether any clinical significance can be established from these findings.

Coherent Electron Optics with Ballistically Coupled Quantum Point Contacts.

The realization of integrated quantum circuits requires precise on-chip control of charge carriers. Aiming at the coherent coupling of distant nanostructures at zero magnetic field, here we study the ballistic electron transport through two quantum point contacts (QPCs) in series in a three terminal configuration. We enhance the coupling between the QPCs by electrostatic focusing using a field effect lens. To study the emission and collection properties of QPCs in detail we combine the electrostatic focusing with magnetic deflection. Comparing our measurements with quantum mechanical and classical calculations we discuss generic features of the quantum circuit and demonstrate how the coherent and ballistic dynamics depend on the details of the QPC confinement potentials.

[Exosomes as immune regulators in head and neck cancer]. / Exosomen als Immunregulatoren in Kopf-Hals-Karzinomen.

Exosomes, virus-sized nanovesicles, are utilized as messenger systems of our body to communicate with other body cells and regulate immune functions. Almost all cells produce exosomes and are able to interact with immune cells in the blood stream and peripheral body areas. Different markers on the surface of exosomes are necessary for immune cell adhesion and interaction. Furthermore, many types of exosome-immune cell interaction, such as surface receptor contact and phagocytosis, are known. As carriers of different cargos, exosomes affect different immune cell types in head and neck cancers: So far, T cells, natural killer cells, macrophages, and dendritic cells have been described in this context. For diagnostic purposes, a combined analysis of different parameters including protein amount, nucleic acid/protein expression, and the immunosuppressive impact of exosomes could empower exosomes as useful tools for evaluation of tumor promotion and progression in the future.

Efficacy and Pharmacokinetics Evaluation of a Single Oral Dose of Afoxolaner against Sarcoptes scabiei in the Porcine Scabies Model for Human Infestation.

Scabies is a major and potentially growing public health problem worldwide with an unmet need for acaricidal agents with greater efficacy and improved pharmacological properties for its treatment. The objective of the present study was to assess the efficacy and describe the pharmacokinetics profile of a novel acaricide, afoxolaner (AFX), in a relevant experimental porcine model. Twelve pigs were experimentally infested and either treated with 2.5 mg/kg single dose oral AFX (n = 4) or 0.2 mg/kg, two doses 8 days apart, oral ivermectin ([IVM] n = 4) or not treated for scabies (n = 4). The response to treatment was assessed by the reduction of mite counts in skin scrapings as well as clinical and pruritus scores over time. Plasma and skin pharmacokinetics profiles for both AFX and IVM were evaluated. AFX efficacy was 100% at days 8 and 14 posttreatment and remained unchanged until the study end (day 45). IVM efficacy was 86% and 97% on days 8 and 14, respectively, with a few mites recovered at the study end. Clinical and pruritus scores decreased in both treated groups and remained constant in the control group. Plasma mean residence times (MRT) were 7.1 ± 2.4 and 1.1 ± 0.2 days for AFX and IVM, respectively. Skin MRT values were 16.2 ± 16.9 and 2.7 ± 0.5 days for AFX and IVM, respectively. Overall, a single oral dose of AFX was efficacious for the treatment of scabies in experimentally infested pigs and showed remarkably long MRTs in plasma and, notably, in the skin.

Antiplatelet and anticoagulant agents in vitreoretinal surgery: a prospective multicenter study involving 804 patients.

PURPOSE: To assess the rate of hemorrhagic complications after vitreoretinal surgery and the influence of antithrombotic agents. METHODS: Hemorrhagic complications of vitreoretinal procedures performed in seven ophthalmologic centers on patients treated or not treated with antiplatelet (AP) or anticoagulant (AC) agents were prospectively collected. Patients' characteristics, surgical techniques, and complications were recorded during surgery and for 1 month after. RESULTS: Eight hundred four procedures were performed between January 2015 and April 2015. Among them, 18.4% were treated with AP agents (n = 148) and 7.8% with AC agents (n = 63), with 18 of them treated with NOACS (new oral anticoagulants). AP or AC agents were continued in 96.5% and 80.7% of cases, respectively. Fifty-three patients (6.6%) developed one or more hemorrhagic complications in one eye during this period. In univariate analysis, AC agents were not associated with hemorrhagic complications (P = 0.329) in contrast to AP (P = 0.005). However, in multivariate analysis, AP agents were no longer associated with hemorrhagic complications and the intraoperative use of endodiathermy was the only factor associated with hemorrhagic complications (P = 0.001). CONCLUSIONS: This study showed that AP and AC agents were not a factor associated with hemorrhagic complications during vitreoretinal surgery. The continuation of these treatments should be considered without risk of severe hemorrhagic complications.

Randomized clinical trial to evaluate the efficacy of prostaglandin F2α to treat purulent vaginal discharge in lactating dairy cows.

The objectives of this study were (1) to assess the effect of purulent vaginal discharge (PVD) on reproductive performance using a 4-point vaginal discharge score (VDS) and (2) to evaluate the effect of PGF2α treatment in cows with PVD on reproductive performance. Holstein cows (n = 2,473) from 1 commercial dairy farm had their vaginal discharge scored at 32 ± 3 d in milk (DIM) using a 4-point scale. Cows were also scored for body condition score and had their ovaries examined using transrectal ultrasound. A VDS-2 or greater was used to define PVD. Cows with PVD were assigned to receive 2 doses of 500 µg of PGF2α analogue (n = 277; Cloprostenol; PGF Veyx forte, Veyx Pharma Ltd., Schwarzenborn, Germany) 14 d apart (odd ear tag number) or remained untreated (n = 272; even ear tag number). All cows not detected in estrus at 90 ± 3 DIM were enrolled into a timed artificial insemination (AI) protocol. The effect of VDS and the effect of PGF2α in cows with PVD on reproductive performance were evaluated separately. First service conception risk (FSCR), time to first AI, and time to pregnancy were used as indicators for reproductive performance. Data were analyzed with Cox's regression and mixed logistic models. The prevalence of PVD was 22.2% (548/2,473). We detected an interaction of parity and VDS for FSCR and time to pregnancy. In primiparous cows, VDS had no effect on FSCR and time to pregnancy. In multiparous cows, VDS had an effect on FSCR and time to pregnancy. Multiparous cows having a VDS-2 or a VDS-3 had decreased odds of pregnancy at first AI compared with cows having a VDS-0. Multiparous cows with VDS-1 or VDS-3 had a decreased hazard of conceiving within 200 DIM. The treatment effect of PGF2α was conditional on parity. In primiparous animals with PVD without a corpus luteum present at 32 DIM, treatment with PGF2α reduced FSCR. Irrespective of the presence of a corpus luteum, treatment with PGF2α decreased the hazard of conceiving within 200 DIM in primiparous cows. Although multiparous cows with PVD treated with PGF2α had increased odds of pregnancy at first AI, no treatment effect was observed on the hazard of conceiving within 200 DIM. Our results do not support the blanket use of PGF2α as a treatment option in postpartum dairy cows having PVD.

Multidrug and Mupirocin Resistance in Environmental Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates from Homes of People Diagnosed with Community-Onset MRSA Infection.

Patients with community-onset (CO) methicillin-resistant Staphylococcus aureus (MRSA) infections contribute to MRSA contamination of the home environment and may be reexposed to MRSA strains from this reservoir. This study evaluates One Health risk factors, which focus on the relationship between humans, animals, and the environment, for the increased prevalence of multiple antimicrobial-resistant MRSA isolates in the home environment. During a trial of patients with CO-MRSA infection, MRSA was isolated from the household environment at the baseline and 3 months later, following randomization of patients and household members to mupirocin-based decolonization therapy or an education control group. Up to two environmental MRSA isolates collected at each visit were tested. MRSA isolates were identified in 68% (65/95) of homes at the baseline (n = 104 isolates) and 51% (33/65) of homes 3 months later (n = 56 isolates). The rates of multidrug resistance (MDR) were 61% among isolates collected at the baseline and 55% among isolates collected at the visit 3 months later. At the baseline, 100% (14/14) of MRSA isolates from rural homes were MDR. While antimicrobial use by humans or pets was associated with an increased risk for the isolation of MDR MRSA from the environment, clindamycin use was not associated with an increased risk for the isolation of MDR MRSA. Incident low-level mupirocin-resistant MRSA strains were isolated at 3 months from 2 (5%) of 39 homes that were randomized to mupirocin treatment but none of the control homes. Among patients recently treated for a CO-MRSA infection, MRSA and MDR MRSA were common contaminants in the home environment. This study contributes to evidence that occupant use of antimicrobial drugs, except for clindamycin, is associated with MDR MRSA in the home environmental reservoir. (This study has been registered at ClinicalTrials.gov under registration no. NCT00966446.)IMPORTANCE MRSA is a common bacterial agent implicated in skin and soft tissue infections (SSTIs) in both community and health care settings. Patients with CO-MRSA infections contribute to environmental MRSA contamination in these settings and may be reexposed to MRSA strains from these reservoirs. People interact with natural and built environments; therefore, understanding the relationships between humans and animals as well as the characteristics of environmental reservoirs is important to advance strategies to combat antimicrobial resistance. Household interactions may influence the frequency and duration of exposure, which in turn may impact the duration of MRSA colonization or the probability for recurrent colonization and infection. Therefore, MRSA contamination of the home environment may contribute to human and animal recolonization and decolonization treatment failure. The aim of this study was to evaluate One Health risk factors that may be amenable to intervention and may influence the recovery of MDR and mupirocin resistance in CO-MRSA isolates.

Does First Nations ancestry modify the association between gestational diabetes and subsequent diabetes: a historical prospective cohort study among women in Manitoba, Canada.

BACKGROUND: Over the past 30 years, the prevalence of diabetes has steadily increased among Canadians, and is particularly evident among First Nations (FN) women. The interplay between FN ancestry, gestational diabetes and the development of subsequent diabetes among mothers remains unclear. METHODS: After excluding known pre-existing diabetes, we explored whether FN ancestry may modify the association between gestational diabetes and post-partum diabetes among women in Manitoba (1981-2011) via a historical prospective cohort database study. We analysed administrative data in the Population Health Research Data Repository using Kaplan-Meier survival analysis and Cox proportional hazards regression. RESULTS: Gestational diabetes was diagnosed in 11 906 of 404 736 deliveries (2.9%), 6.7% of FN and 2.2% of non-FN pregnant women (P < 0.0001). Post-partum diabetes during ≤ 30 years follow-up was more than three times higher among FN women than among non-FN women (P < 0.0001). Diabetes developed in 76.0% of FN and 56.2% of non-FN women with gestational diabetes within the follow-up period. The hazard ratio of gestational diabetes for post-partum diabetes was 10.6 among non-FN women and 5.4 among FN women. Other factors associated with a higher risk of diabetes included lower family income among FN and non-FN women and rural/remote residences among FN women. Among non-FN women, urban residence was associated with a higher risk of diabetes. CONCLUSION: Gestational diabetes increases post-partum diabetes in FN and non-FN women. FN women had substantially more gestational diabetes or post-partum diabetes than non-FN women, partially due to socio-economic and environmental barriers. Reductions in gestational diabetes and socio-economic inequalities are required to prevent diabetes in women, particularly in FN population.

[Management of anesthesia in endovascular interventions]. / Anästhesiologisches Management bei endovaskulären Gefäßeingriffen.

Cardiovascular diseases are one of the leading causes of morbidity and mortality in Germany. In these patients, the high-risk profile necessitates an interdisciplinary and multimodal approach to treatment. Endovascular interventions and vascular surgery have become established as an important element of this strategy in the past; however, the different anatomical localizations of pathological vascular alterations make it necessary to use a wide spectrum of procedural options and methods; therefore, the requirements for management of anesthesia are variable and necessitate a differentiated approach. Endovascular procedures can be carried out with the patient under general or regional anesthesia (RA); however, in the currently available literature there is no evidence for an advantage of RA over general anesthesia regarding morbidity and mortality, although a reduction in pulmonary complications could be found for some endovascular interventions. Epidural and spinal RA procedures should be carefully considered with respect to the risk-benefit ratio and consideration of the recent guidelines on anesthesia against the background of the current study situation and the regular use of therapy with anticoagulants. The following article elucidates the specific characteristics of anesthesia management as exemplified by some selected endovascular interventions.

[Total Pancreatectomy and Islet Autotransplantation in a Child with Recurrent Pancreatitis]. / Totale Pankreatektomie und Inselautotransplantation bei einem Kind mit chronisch rezidivierender Pankreatitis.

INTRODUCTION: Hereditary pancreatitis in children is rare. The indications for surgery in these children are complications and severe pain that cannot be managed by conservative treatment. Surgical treatment options are duodenum preserving resections as well as drainage procedures. Recurrences are common following theses surgical procedures, because usually the whole pancreas is affected. The majority of the children with symptomatic hereditary pancreatitis are free of pain after total pancreatectomy. When total pancreatectomy is combined with islet autotransplantation, pancreoprivic diabetes can be attenuated or even prevented. The principle of spleen-preserving total pancreatectomy combined with subsequent islet autotransplantation is shown in a case of a 10-year-old child with chronic recurrent pancreatitis in this video. INDICATION: Symptomatic chronic hereditary pancreatitis in children. PROCEDURE: Spleen-preserving total pancreatectomy, reconstruction with hepatico-jejunostomy and duodeno-jejunostomy, islet autotransplantation via portal vein. CONCLUSION: If the surgeon has appropriate experience, spleen-preserving total pancreatectomy is a safe procedure. In combination with islet autotransplantation, it may attenuate or prevent diabetes mellitus associated with total pancreatectomy. In highly selected pediatric patients, this surgical procedure has a major benefit compared to a purely symptomatic therapy.

Islet transplantation at the Dresden diabetes center: five years' experience.

For the majority of patients with type 1 diabetes intensive insulin therapy is effective and safe for maintaining glycemia and minimizing diabetes-associated complications. However, a rare number of patients show highly labile metabolic control and experience repeated and unpredictable hypoglycemic episodes. Such condition is often caused by defective counterregulatory mechanisms and autonomous neuropathy. Patients are at high risk for severe acute and chronic complications, and quality of life is considerably impaired. For this small subset of patients, restoration of endogenous insulin secretion can substantially improve metabolic control and quality of life. In our experience, this is irrespective of insulin independency. Here, we report on our 5 years' experience with implementing islet transplantation as a potential treatment option for type 1 diabetes. All patients were treated by long-term insulin pump therapy prior to enrolment. The main indication was severely unstable diabetes and repeated hypoglycemia. From 2008 to 2013, 10 patients have been transplanted with single islet infusion; mean follow-up time was 35 months. All patients show persistent graft function, stable glycemic control with a reduction in HbA1c in the absence of hypoglycemia. All patients are kept on minimal exogenous insulin. In conclusion, islet transplantation can be an excellent therapy for selected patients. Key prerequisite for success is a strict indication. The primary goal for islet transplantation should be stabile glycemia and prevention of hypoglycemia rather than insulin independence. In fact, maintaining minimal exogenous insulin may protect the islet graft from metabolic stress and even prolong islet graft function.

Experimentally elevated levels of testosterone at independence reduce fitness in a territorial bird.

Environmental conditions and individual strategies in early life may have a profound effect on fitness. A critical moment in the life of an organism occurs when an individual reaches independence and stops receiving benefits from its relatives. Understanding the consequences of individual strategies at the time of independence requires quantification of their fitness effects. We explored this period in the Red Grouse (Lagopus lagopus scoticus). In this system, testosterone and parasite (Trichostrongylus tenuis) levels are known to influence survival and reproduction, the two key components of individual fitness. We experimentally and simultaneously manipulated testosterone and parasites at three levels (high, intermediate, and control levels for both factors) in 195 young males in five populations using a factorial experimental design. We explored the effects of our treatments on fitness by monitoring reproduction and survival throughout the life of all males and estimating lambda(ind), a rate-sensitive index of fitness. Parasite challenges increased the number of worms with a time lag, as previously found. However, we did not find significant effects of parasite manipulations on fitness, possibly because parasite abundance did not increase to harmful levels. Our hormone manipulation was successful at increasing testosterone at three different levels. Such increases in hormone levels decreased overall fitness. This was caused by reduced offspring production in the first breeding attempt rather than by any effect of the treatment on bird survival. Our results highlight that investing in high testosterone levels at independence, a strategy that might enhance short-term recruitment probability in territorial species such as Red Grouse, has a fitness cost, and can influence the resolution of the trade-off between reproduction and survival later in life.

Characterization of qubit dephasing by Landau-Zener-Stückelberg-Majorana interferometry.

Controlling coherent interaction at avoided crossings and the dynamics there is at the heart of quantum information processing. A particularly intriguing dynamics is observed in the Landau-Zener regime, where periodic passages through the avoided crossing result in an interference pattern carrying information about qubit properties. In this Letter, we demonstrate a straightforward method, based on steady-state experiments, to obtain all relevant information about a qubit, including complex environmental influences. We use a two-electron charge qubit defined in a lateral double quantum dot as test system and demonstrate a long coherence time of T2 ≃ 200 ns, which is limited by electron-phonon interaction.

Intra-sexual competition alters the relationship between testosterone and ornament expression in a wild territorial bird.

In a reliable signalling system, individual quality is expected to mediate the costs associated with ornamental displays, with relatively lower costs being paid by individuals of higher quality. These relative costs should depend not only on individual quality, but also on levels of intra-sexual competition. We explored the current and delayed effects that testosterone implants have on bird ornamentation in populations with contrasted population densities, as a proxy for intra-sexual competition. In a replicated experiment, we manipulated testosterone in 196 yearling male red grouse Lagopus lagopus scoticus in autumn in populations of high and low levels of intra-sexual competition. Males were assigned to one of three exogenous testosterone (T) treatments: empty implants (T0), small T implants (T1) or larger T implants (T2). We monitored subsequent changes in testosterone levels, ornament size and carotenoid-based colouration, carotenoid levels and body condition from autumn to spring. Testosterone implants increased testosterone levels, comb redness and comb size, and decreased body condition but these effects depended on levels of intra-sexual competition. Specifically, T2-implanted birds increased testosterone levels and comb size more, and reduced body condition more, in populations where intra-sexual competition was low. In the following spring, testosterone levels of T2-treated birds kept increasing in populations where intra-sexual competition was high but not in populations where intra-sexual competition was low. Our results highlight that levels of intra-sexual competition alter the relationship between testosterone levels and ornament expression, influencing their condition-dependence; they also indicate that the outcome of standard hormone manipulation conducted in free-living animals vary depending on the population context.

Toxicity of antihypertensives in unintentional poisoning of young children.

BACKGROUND: Knowledge is limited about the toxicity of unintentional exposure to antihypertensives in young children (0-6 years of age). OBJECTIVE: Our aim was to research symptoms and poisoning severity in unintentional poisonings in this group of age and determine adequate poisoning management. METHODS: We performed a 10-year retrospective, explorative analysis of the Mainz Poison Center/Germany database with regard to circumstances of poison exposure, dosage, symptoms, and treatment. To be able to relate drug exposure with reported symptoms, analyses were restricted to single drug exposures. Written follow-up information was obtained in about 50% of all cases. RESULTS: A total of 1489 cases were analyzed, of which 957 were single drug exposures with 421 exposures to beta-blocking agents, 364 to inhibitors of the renin-angiotensin system, 122 to calcium channel blockers, and 50 to antiadrenergic drugs. No severe (Poisoning Severity Score [PSS]=3) or fatal poisonings (PSS=4) were reported and, with the exception of atenolol, propranolol, irbesartan, isradipin, clonidine, and moxonidine, no poisonings with a PSS>1. We did not find a significant relationship between dosage, release formulation and symptoms, or PSS. All patients fully recovered without specific treatment. CONCLUSIONS: In young children with unintentional, single drug exposure to the most popular antihypertensive medication (i.e., metoprolol, bisoprolol, ramipril, enalapril, lisinopril, captopril, candesartan, valsartan, amlodipine, and verapamil), only mild symptoms occurred, and hospital evaluation is not a must. However, children with recent exposure to clonidine or moxonidine should be evaluated at a hospital due to an increased likelihood of poisonings of at least moderate severity.

[Epidemiological research with data from cancer registries: a program financed by the German Cancer Aid (Deutsche Krebshilfe, DKH)]. / Epidemiologische Forschung mit den Daten der Krebsregister : Ein von der Deutschen Krebshilfe (DKH) gefördertes Programm.

In 2007, the German Cancer Aid started a program to promote epidemiological research with data from cancer registries. Within this program, ten projects with various epidemiological research questions were funded. The program was a major boost for the use of data from population-based cancer registries and was an important milestone for cancer epidemiology in Germany.

Laparoscopic resection rectopexy (RRP) combined with mesh sacrocolpopexy (SCP) for obstructed defecation syndrome with pelvic organ prolapse in an interdisciplinary approach.

Background: Obstructive defecation syndrome (ODS) is frequently associated with pelvic organ prolapse (POP) and compromises the quality of life in affected patients. In cases conservative treatment fails surgical therapy is required. Objectives: The video case study combines a laparoscopic resection rectopexy (RRP) with a mesh sacrocolpopexy (SCP) in an interdisciplinary surgical approach. Materials and Methods: In this video an 86-year-old woman with ODS and POP, suffering from a dolichocolon with rectal intussusception, an apical prolapse after total hysterectomy 1990, and occasional stress urinary incontinence underwent interdisciplinary laparoscopic surgery. A tubular anterior rectal and sigmoid resection with suture rectopexy as in a resection rectopexy (RRP) was combined with a sacrocolpopexy (SCP) using a synthetic mesh. Main outcome measures: Surgical outcome including postoperative morbidity, functional bowel evacuation, and POP reconstitution as in POP-Q score after surgery were documented. Results: No intra- or postoperative complications occurred. At 6 months follow-up clinical outcomes for ODS, bowel dysfunction, and faecal control were improved. Anatomical outcome for POP and stress urinary incontinence symptoms were corrected. Conclusions: We report a promising interdisciplinary surgical approach as a single treatment option for the complex medical condition of women suffering from ODS and POP combining laparoscopic RRP with SCP. This surgical approach proved to be feasible, safe, and effective.

[Surgical technique for pancreas transplantation]. / Die chirurgische Technik der Pankreastransplantation.

OBJECTIVE: The transplantation of a cadaveric donor pancreas represents a therapeutic option for the type 1 diabetic. A precondition is the proof of negative serum C-peptide after glucagon stimulation (< 0.02 ng/ml) as it is found in the typical patient with type 1 or a pancreoprive diabetes. The pancreas can be transplanted alone (PTA) or after a kidney (PAK), either following a preceding living related or cadaveric kidney transplantation. The majority of pancreata worldwide are transplanted simultaneously with a kidney (SPK) in stage 4 and 5 (eGFR < 29 ml/min) of chronic kidney disease. The beneficial effect of physiological glucose regulation on mortality, kidney failure and diabetic complications (cardiovascular, neuropathy, retinopathy) is well established. Patient survival rate at 1 year after transplantation is above 90 %, pancreas graft survival overall after 1 year is about 80 %. INDICATIONS: Type 1 diabetic patients with recurrent hypoglycemic episodes or major complications due to dysregulated glucose metabolism qualify for pancreas transplantation alone in case of a stable kidney function. Patients with chronic kidney disease stage 4 and 5 are candidates for SPK. PROCEDURE: Pancreatic transplantation into the right iliac fossa. CONCLUSION: Although technically demanding, pancreas transplantation is safely performable with a low periprocedural morbidity and mortality. Potential perioperative complications include inflammation, rejection or graft thrombosis. After a successful transplantation, long-term physiological glucose regulation can be achieved which results in a prolonged life expectancy and quality of life in type 1 diabetic patients.

Simultaneous determination of electrical conductivity and thickness of nonmagnetic metallic foils using two-sided multifrequency eddy current techniques.

In this paper, we describe a simple method for performing multifrequency eddy current characterization of free-standing uniform-thickness metallic foils using a forked inductive coil arrangement. The method involves measuring the mutual inductance between two coils when a foil is present between the coils, and when it is not present; the ratio of these mutual inductances is compared with an analytical solution, and foil conductivity, thickness, and sheet resistance are simultaneously estimated using numerical inversion and least-squares fitting. This method was used to characterize 34 non-ferrous metallic samples with thicknesses between 50 and 640 µm and with conductivities between 0.8 × 107 and 5.8 × 107 S/m. The estimated thicknesses from eddy current characterization agreed well with those measured using confocal optical techniques; the two approaches agreed to within 1 µm for samples that were thinner than 200 µm, and to within 0.5% for samples that had a thickness of 200 µm or greater. The estimated conductivities from eddy current characterization were in close agreement with expected values, given knowledge of the materials used. A particular strength of this approach is that the instrumentation needed is broadly available in research and development laboratories and the associated fixturing is easy to manufacture and assemble. A calibration procedure is described that can be used to reduce errors from geometric uncertainties. This calibration requires a sample that has only a known conductivity or thickness; both do not need to be known. The method described herein is likely extensible to conductivities and thickness well outside the ranges measured as part of this work.