Predictors of reoperation after lung volume reduction surgery.

OBJECTIVES: Lung volume reduction surgery (LVRS) has proven an effective treatment for emphysema, by decreasing hyperinflation and improving lung function, activity level and reducing dyspnoea. However, postoperative air leak is an important complication, often leading to reoperation. Our aim was to analyse reoperations after LVRS and identify potential predictors. METHODS: Consecutive single-centre unilateral VATS LVRS performed from 2017 to 2022 were included. Typically, 3-5 minor resections were made using vascular magazines without buttressing. Data were obtained from an institutional database and analysed. Multivariable logistic regression was used to identify predictors of reoperation. Number and location of injuries were registered. RESULTS: In total, 191 patients were included, 25 were reoperated (13%). In 21 patients, the indication for reoperation was substantial air leak, 3 patients bleeding and 1 patient empyema. Length of stay (LOS) was 21 (11-33) vs. 5 days (3-11), respectively. Only 3 injuries were in the stapler line, 13 within < 2cm and 15 injuries were in another site. Multivariable logistic regression analysis showed that decreasing DLCO increased risk of reoperation, OR 1.1 (1.03, 1.18, P = 0.005). Resections in only one lobe, compared to resections in multiple lobes, were also a risk factor OR 3.10 (1.17, 9.32, P = 0.03). Patients undergoing reoperation had significantly increased 30-day mortality, OR 5.52 (1.03, 26.69, P = 0.02). CONCLUSIONS: Our incidence of reoperation after LVRS was 13% leading to prolonged LOS and increased 30-day mortality. Low DLCO and resections in a single lobe were significant predictors of reoperation. The air leak was usually not localized in the stapler line.

Correction to: Detection of Candidatus Neoehrlichia mikurensis in Norway up to the northern limit of Ixodes ricinus distribution using a novel real time PCR test targeting the groEL gene.

After publication of our article [1] it came to our notice that the source of the sequence for the control plasmid, pNeo (Materials and methods: Controls) was incorrectly stated as AB094461. The correct accession number is AB074461. The authors apologize for any confusion this may have caused.

Revealing Well-Defined Soluble States during Amyloid Fibril Formation by Multilinear Analysis of NMR Diffusion Data.

Amyloid fibril formation is a hallmark of neurodegenerative disease caused by protein aggregation. Oligomeric protein states that arise during the process of fibril formation often coexist with mature fibrils and are known to cause cell death in disease model systems. Progress in this field depends critically on development of analytical methods that can provide information about the mechanisms and species involved in oligomerization and fibril formation. Here, we demonstrate how the powerful combination of diffusion NMR and multilinear data analysis can efficiently disentangle the number of involved species, their kinetic rates of formation or disappearance, spectral contributions, and diffusion coefficients, even without prior knowledge of the time evolution of the process or chemical shift assignments of the various species. Using this method we identify oligomeric species that form transiently during aggregation of human superoxide dismutase 1 (SOD1), which is known to form misfolded aggregates in patients with amyotrophic lateral sclerosis. Specifically, over a time course of 42 days, during which SOD1 fibrils form, we detect the disappearance of the native monomeric species, formation of a partially unfolded intermediate in the dimer to tetramer size range, subsequent formation of a distinct similarly sized species that dominates the final spectrum detected by solution NMR, and concomitant appearance of small peptide fragments.

Detection of Candidatus Neoehrlichia mikurensis in Norway up to the northern limit of Ixodes ricinus distribution using a novel real time PCR test targeting the groEL gene.

BACKGROUND: Candidatus Neoehrlichia mikurensis is an emerging tick-borne pathogen. It is widely distributed in Ixodes ricinus ticks in Europe, but knowledge of its distribution in Norway, where I. ricinus reaches its northern limit, is limited. In this study we have developed a real time PCR test for Ca. N. mikurensis and used it to investigate the distribution of Ca. N. mikurensis in Norway. RESULTS: Real time PCR targeting the groEL gene was developed and shown to be highly sensitive. It was used to detect Ca. N. mikurensis in 1651 I. ricinus nymphs and adults collected from twelve locations in Norway, from the eastern Oslo Fjord in the south to near the Arctic Circle in the north. The overall prevalence was 6.5% and varied locally between 0 and 16%. Prevalence in adults and nymphs was similar, suggesting that ticks acquire Ca. N. mikurensis predominantly during their first blood meal. In addition, 123 larvae were investigated; Ca. N. mikurensis was not found in larvae, suggesting that transovarial transmission is rare or absent. Sequence analysis suggests that a single variant dominates in Norway. CONCLUSIONS: Ca. N. mikurensis is widespread and common in ticks in Norway and reaches up to their northern limit near the Arctic Circle. Ticks appear to acquire Ca. N. mikurensis during their first blood meal. No evidence for transovarial transmission was found.

Cost and clinical outcome of islet transplantation in Norway 2010-2015.

Islet transplantation is a minimally invasive ß-cell replacement strategy. Islet transplantation is a reimbursed treatment in Norway. Here, we summarize the cost and clinical outcome of 31 islet transplantations performed at Oslo University Hospital (OUS) from January 2010 to June 2015. Patients were retrospectively divided into three groups. Thirteen patients received either one or two islet transplantation alone (ITA), while five patients received islet transplantation after previous solid organ transplantation. For the group receiving 2 ITA, Kaplan-Meier estimates show an insulin independence of 20% more than 4 years after their last transplantation. An estimated 70% maintain at least partial graft function, defined as fasting C-peptide >0.1 nmol L-1 , and 47% maintain a HbA1c below 6.5% or 2 percent points lower than before ITA. For all groups combined, we estimate that 44% of the patients have a 50% reduction in insulin requirement 4 years after the initial islet transplantation. The average cost for an islet transplantation procedure was 347 297±60 588 NOK, or 35 424±6182 EUR, of which isolation expenses represent 34%. We hereby add to the common pool of growing experience with islet transplantation and also describe the cost of the treatment at our center.

In-Air and Underwater Hearing in the Great Cormorant (Phalacrocorax carbo sinensis).

Hearing thresholds of a great cormorant (Phalacrocorax carbo) were measured in air and under water using psychophysics. The lowest thresholds were at 2 kHz (45 dB re 20 µPa root-mean-square [rms] in air and 79 dB re 1 µPa rms in water). Auditory brainstem response measurements on one anesthetized bird in air indicated an audiogram with a shape that resembled the one achieved by psychophysics. This study suggests that cormorants have rather poor in-air hearing abilities compared with other similar-size birds. The hearing capabilities in water are better than what would have been expected for a purely in-air adapted ear.

Adenine phosphoribosyltransferase from Sulfolobus solfataricus is an enzyme with unusual kinetic properties and a crystal structure that suggests it evolved from a 6-oxopurine phosphoribosyltransferase.

The adenine phosphoribosyltransferase (APRTase) encoded by the open reading frame SSO2342 of Sulfolobus solfataricus P2 was subjected to crystallographic, kinetic, and ligand binding analyses. The enzyme forms dimers in solution and in the crystals, and binds one molecule of the reactants 5-phosphoribosyl-α-1-pyrophosphate (PRPP) and adenine or the product adenosine monophosphate (AMP) or the inhibitor adenosine diphosphate (ADP) in each active site. The individual subunit adopts an overall structure that resembles a 6-oxopurine phosphoribosyltransferase (PRTase) more than known APRTases implying that APRT functionality in Crenarchaeotae has its evolutionary origin in this family of PRTases. Only the N-terminal two-thirds of the polypeptide chain folds as a traditional type I PRTase with a five-stranded ß-sheet surrounded by helices. The C-terminal third adopts an unusual three-helix bundle structure that together with the nucleobase-binding loop undergoes a conformational change upon binding of adenine and phosphate resulting in a slight contraction of the active site. The inhibitor ADP binds like the product AMP with both the α- and ß-phosphates occupying the 5'-phosphoribosyl binding site. The enzyme shows activity over a wide pH range, and the kinetic and ligand binding properties depend on both pH and the presence/absence of phosphate in the buffers. A slow hydrolysis of PRPP to ribose 5-phosphate and pyrophosphate, catalyzed by the enzyme, may be facilitated by elements in the C-terminal three-helix bundle part of the protein.

Intracellular sirolimus concentration is reduced by tacrolimus in human pancreatic islets in vitro.

MAIN PROBLEM: Islet transplantation has become a promising treatment for type 1 diabetes. However, immunosuppressive drugs used today cause islet deterioration and modification strategies are necessary. But little is known about pharmacokinetics interactions and intracellular concentrations of immunosuppressive drugs in human islets. METHODS: We determined the pharmacokinetics of tacrolimus and sirolimus in islets by measuring intracellular concentration after exposure alone or in combination at two different doses up to 48 h. A quantification technique established in our laboratory using a Micromass Quattro micro API MS/MS-instrument with electrospray ionization was used. Islets function was measured by oxygen consumption rates. Presence of drug transporters OATP1B1 and ABCB1 and metabolizing enzyme CYP3A4 in islets were quantified using real-time quantitative PCR. RESULTS: Islets incubated with tacrolimus and sirolimus had a significant decrease in intracellular concentration of sirolimus compared to sirolimus alone. Reduced intracellular sirolimus concentration was followed by increased p70S6k phosphorylation suggesting preservation of the mTOR-signaling pathway. Drug transporters OATP1B1 and ABCB1 and enzyme CYP3A4 were expressed in human islets, but were not involved in the reduced sirolimus concentration by tacrolimus. CONCLUSION: These findings provide new knowledge of the drug interaction between tacrolimus and sirolimus, suggesting that tacrolimus has an inhibitory effect on the intracellular concentration of sirolimus in human islets.

Graft function 1 year after pregnancy in an islet-transplanted patient.

Pancreatic islet transplantation is a treatment option for patients with type 1 diabetes (T1D), but pregnancy has generally not been advised for women after receiving an islet allograft. We hereby describe what is to our knowledge the first successful pregnancy and persistent graft function in a woman 4 years after her initial islet transplantation. A 37-year-old woman with brittle type 1 diabetes was transplanted with two separate islet graft infusions, eventually becoming insulin independent. Ten months after her second transplantation, her immunosuppression was switched from tacrolimus and sirolimus to tacrolimus, azathioprine, and prednisolone, due to her wish to become pregnant. She became pregnant one year later, and after 38 weeks of uncomplicated pregnancy, she gave birth to a healthy child by C-section. The current report suggests that pregnancy and childbirth can be accomplished after islet transplantation without loss of islet graft function.

The pKa value and accessibility of cysteine residues are key determinants for protein substrate discrimination by glutaredoxin.

The enzyme glutaredoxin catalyzes glutathione exchange, but little is known about its interaction with protein substrates. Very different proteins are substrates in vitro, and the enzyme seems to have low requirements for specific protein interactions. Here we present a systematic investigation of the interaction between human glutaredoxin 1 and glutathionylated variants of a single model protein. Thus, single cysteine variants of acyl-coenzyme A binding protein were produced creating a set of substrates in the same protein background. The rate constants for deglutathionylation differ by more than 2 orders of magnitude between the best (k1 = 1.75 × 10(5) M(-1) s(-1)) and the worst substrate (k1 = 4 × 10(2) M(-1) s(-1)). The pKa values of the substrate cysteine residues were determined by NMR spectroscopy and found to vary from 8.2 to 9.9. Rates of glutaredoxin 1-catalyzed deglutathionylation were assessed with respect to substrate cysteine pKa values, cysteine residue accessibility, local stability, and backbone dynamics. Good substrates are characterized by a combination of high accessibility of the glutathionylated site and low pKa of the cysteine residue.

Specificities and pH profiles of adenine and hypoxanthine-guanine-xanthine phosphoribosyltransferases (nucleotide synthases) of the thermoacidophile archaeon Sulfolobus solfataricus.

Two open reading frames in the genome of Sulfolobus solfataricus (SSO2342 [corrected] and SSO2424) were cloned and expressed in E. coli. The protein products were purified and their enzymatic activity characterized. Although SSO2342 [corrected] was annotated as a gene (gpT-1) encoding a 6-oxopurine phosphoribosyltransferase (PRTase), the protein product turned out to be a PRTase highly specific for adenine and we suggest that the reading frame should be renamed apT. The other reading frame SSO2424 (gpT-2) proved to be a true 6-oxopurine PRTase active with hypoxanthine, xanthine and guanine as substrates, and we suggest that the gene should be renamed gpT. Both enzymes exhibited unusual profiles of activity versus pH. The adenine PRTase showed the highest activity at pH 7.5-8.5, but had a distinct peak of activity also at pH 4.5. The 6-oxo PRTase showed maximal activity with hypoxanthine and guanine around pH 4.5, while maximal activity with xanthine was observed at pH 7.5. We discuss likely reasons why SSO2342 [corrected] in S. solfataricus and similar open reading frames in other Crenarchaeota could not be identified as genes encoding APRTase.

Protein dielectric constants determined from NMR chemical shift perturbations.

Understanding the connection between protein structure and function requires a quantitative understanding of electrostatic effects. Structure-based electrostatic calculations are essential for this purpose, but their use has been limited by a long-standing discussion on which value to use for the dielectric constants (ε(eff) and ε(p)) required in Coulombic and Poisson-Boltzmann models. The currently used values for ε(eff) and ε(p) are essentially empirical parameters calibrated against thermodynamic properties that are indirect measurements of protein electric fields. We determine optimal values for ε(eff) and ε(p) by measuring protein electric fields in solution using direct detection of NMR chemical shift perturbations (CSPs). We measured CSPs in 14 proteins to get a broad and general characterization of electric fields. Coulomb's law reproduces the measured CSPs optimally with a protein dielectric constant (ε(eff)) from 3 to 13, with an optimal value across all proteins of 6.5. However, when the water-protein interface is treated with finite difference Poisson-Boltzmann calculations, the optimal protein dielectric constant (ε(p)) ranged from 2 to 5 with an optimum of 3. It is striking how similar this value is to the dielectric constant of 2-4 measured for protein powders and how different it is from the ε(p) of 6-20 used in models based on the Poisson-Boltzmann equation when calculating thermodynamic parameters. Because the value of ε(p) = 3 is obtained by analysis of NMR chemical shift perturbations instead of thermodynamic parameters such as pK(a) values, it is likely to describe only the electric field and thus represent a more general, intrinsic, and transferable ε(p) common to most folded proteins.

Identification of Distinct Soluble States During Fibril Formation Using Multilinear Analysis of NMR Diffusion Data.

Protein misfolding and self-assembling into amyloid structures are associated with a number of diseases. Characterization of protein amyloid formation reactions is a challenging task as transient populations of multiple species are involved. Here we outline a method for identification and characterization of the individual soluble states during protein amyloid formation. The method combines NMR translational diffusion measurements with multilinear data analysis.

Severe Emphysema Treated with Bilateral Lung Sealant: A Case Series with Long-Term Follow-Up.

Bronchoscopic lung volume reduction (BLVR) for emphysematous hyperinflation has evolved during the last two decades as an alternative to lung volume reduction surgery (LVRS) with lower morbidity and mortality. Emphysematous lung sealant (ELS) is a form of BLVR specifically aimed at patients with collateral ventilation (CV), shown to have favorable outcomes in lung function up to two years. This case series presents four emphysema patients treated bilaterally with ELS, with a follow-up period up to six years. Two of the patients had previously undergone LVRS and BLVR with valves. Following ELS installment, all patients showed positive changes in spirometric values, with varying durability between one and five years. Three patients reported an overall improvement in subjective symptoms after treatment as measured by the COPD Assessment Test (CAT), one of which had lasting improvement even after five years (CAT from 20 to 13). Two of the four treated patients suffered recurrent respiratory exacerbations and pneumonias requiring hospitalization. They both went on to receive lung transplantation within one and three years. This report concludes that ELS has a meaningful effect on reducing hyperinflation in emphysema with improving pulmonary function tests, and relieving symptoms of dyspnea for up to five years. Unfortunately, some patients develop complications leading to recurrent exacerbations. We were not able to show a survival benefit with ELS treatment. This article highlights the need for further research in order to predict who will benefit from this treatment and how to handle CV-positive patients.

The Danish respiratory society guideline for long-term high flow nasal cannula treatment, with or without supplementary oxygen.

Introduction: Long-term High Flow Nasal Cannula (LT-HFNC), defined as High Flow Nasal Cannula treatment provided to patients with chronic pulmonary conditions during stable phases, has emerged as a home treatment in different categories of patients with chronic lung diseases in recent years. Methods: This paper summarizes the physiological effects of LT-HFNC and evaluates the clinical knowledge to date about treatment in patients with chronic obstructive lung disease, interstitial lung disease and bronchiectasis. The guideline is translated and summarized in this paper and presented unabridged as an appendix to the paper. Results: The paper describes the working process behind the Danish Respiratory Society's National guideline for treatment of stable disease, which has been written to support clinicians in both evidence-based decision making and practical issues concerning the treatment.

Evaluation of single-fraction high dose FLASH radiotherapy in a cohort of canine oral cancer patients.

Background: FLASH radiotherapy (RT) is a novel method for delivering ionizing radiation, which has been shown in preclinical studies to have a normal tissue sparing effect and to maintain anticancer efficacy as compared to conventional RT. Treatment of head and neck tumors with conventional RT is commonly associated with severe toxicity, hence the normal tissue sparing effect of FLASH RT potentially makes it especially advantageous for treating oral tumors. In this work, the objective was to study the adverse effects of dogs with spontaneous oral tumors treated with FLASH RT. Methods: Privately-owned dogs with macroscopic malignant tumors of the oral cavity were treated with a single fraction of ≥30Gy electron FLASH RT and subsequently followed for 12 months. A modified conventional linear accelerator was used to deliver the FLASH RT. Results: Eleven dogs were enrolled in this prospective study. High grade adverse effects were common, especially if bone was included in the treatment field. Four out of six dogs, who had bone in their treatment field and lived at least 5 months after RT, developed osteoradionecrosis at 3-12 months post treatment. The treatment was overall effective with 8/11 complete clinical responses and 3/11 partial responses. Conclusion: This study shows that single-fraction high dose FLASH RT was generally effective in this mixed group of malignant oral tumors, but the risk of osteoradionecrosis is a serious clinical concern. It is possible that the risk of osteonecrosis can be mitigated through fractionation and improved dose conformity, which needs to be addressed before moving forward with clinical trials in human cancer patients.

Brassiere Cup Size Agreement between Patients and Plastic Surgeons: Do Surgeons and Patients Speak the Same Size Language?

Patients undergoing plastic surgery of the breasts often communicate their size expectations as a brassiere cup size. However, multiple factors may cause a miscommunication between the surgeon and patient when brassiere cup size is used as a measure of results. The aim of this study was to determine the degree of agreement between disclosed and estimated brassiere cup size and also interrater agreement. Methods: Three-dimensional (3D) scans of 32 subjects were evaluated by 10 plastic surgeons estimating cup size using the American brassiere system. The surgeons were blinded to all parameters, including the 3D surface software-derived volume measures of the Vectra scan. The 3D scans of the anterior torsos were viewed. The plastic surgeons' estimations were compared with the cup sizes stated by the subjects (disclosed cup size), using simple and weighted Kappa statistics. Results: Agreement between the estimated and disclosed brassiere sizes was only slight (0.1479 ± 0.0605) using a simple Kappa analysis. Even when a Fleiss-Cohen-weighted comparison was used, only moderate agreement (0.6231 ± 0.0589) was found. The interrater agreement intraclass correlation coefficient was 0.705. Rater accuracy varied. The percentage of time spent in cosmetic practice and gender were not significantly correlated with accuracy. Conclusions: Agreement between cup size disclosed by subjects and estimates by plastic surgeons was low. A miscommunication between the surgeon and patient may occur when using brassiere sizes to communicate wishes and estimates in procedures that involve changes in breast volume.

Surface guided electron FLASH radiotherapy for canine cancer patients.

BACKGROUND: During recent years FLASH radiotherapy (FLASH-RT) has shown promising results in radiation oncology, with the potential to spare normal tissue while maintaining the antitumor effects. The high speed of the FLASH-RT delivery increases the need for fast and precise motion monitoring to avoid underdosing the target. Surface guided radiotherapy (SGRT) uses surface imaging (SI) to render a 3D surface of the patient. SI provides real-time motion monitoring and has a large scanning field of view, covering off-isocentric positions. However, SI has so far only been used for human patients with conventional setup and treatment. PURPOSE: The aim of this study was to investigate the performance of SI as a motion management tool during electron FLASH-RT of canine cancer patients. METHODS: To evaluate the SI system's ability to render surfaces of fur, three fur-like blankets in white, grey, and black were used to imitate the surface of canine patients and the camera settings were optimized for each blanket. Phantom measurements using the fur blankets were carried out, simulating respiratory motion and sudden shift. Respiratory motion was simulated using the QUASAR Respiratory Motion Phantom with the fur blankets placed on the phantom platform, which moved 10 mm vertically with a simulated respiratory period of 4 s. Sudden motion was simulated with an in-house developed phantom, consisting of a platform which was moved vertically in a stepwise motion at a chosen frequency. For sudden measurements, 1, 2, 3, 4, 5, 6, 7, and 10 Hz were measured. All measurements were both carried out at the conventional source-to-surface distance (SSD) of 100 cm, and in the locally used FLASH-RT setup at SSD = 70 cm. The capability of the SI system to reproduce the simulated motion and the sampling time were evaluated. As an initial step towards clinical implementation, the feasibility of SI for surface guided FLASH-RT was evaluated for 11 canine cancer patients. RESULTS: The SI camera was capable of rendering surfaces for all blankets. The deviation between simulated and measured mean peak-to-peak breathing amplitude was within 0.6 mm for all blankets. The sampling time was generally higher for the black fur than for the white and grey fur, for the measurement of both respiratory and sudden motion. The SI system could measure sudden motion within 62.5 ms and detect motion with a frequency of 10 Hz. The feasibility study of the canine patients showed that the SI system could be an important tool to ensure patient safety. By using this system we could ensure and document that 10 out of 11 canine patients had a total vector offset from the reference setup position <2 mm immediately before and after irradiation. CONCLUSIONS: We have shown that SI can be used for surface guided FLASH-RT of canine patients. The SI system is currently not fast enough to interrupt a FLASH-RT beam while irradiating but with the short sampling time sudden motion can be detected. The beam can therefore be held just prior to irradiation, preventing treatment errors such as underdosing the target.

A fluorescent probe which allows highly specific thiol labeling at low pH.

Determination of the thiol-disulfide status in biological systems is challenging as redox pools are easily perturbed during sample preparation. This is particularly pertinent under neutral to mildly alkaline conditions typically required for alkylation of thiols. Here we describe the synthesis and properties of a thiol-specific reagent, fluorescent cyclic activated disulfide (FCAD), which includes the fluorescein moiety as fluorophore and utilizes a variation of thiol-disulfide exchange chemistry. The leaving-group character of FCAD makes it reactive at pH 3, allowing modification at low pH, limiting thiol-disulfide exchange. Different applications are demonstrated including picomolar thiol detection, determination of redox potentials, and in-gel detection of labeled proteins.

Primiparous women differ from multiparous women after early discharge regarding breastfeeding, anxiety, and insecurity: A prospective cohort study.

INTRODUCTION: Breastfeeding and factors influencing breastfeeding are essential when considering the association between parity and neonatal and maternal morbidity risks when mothers are discharged within 24 hours after birth. However, there is a lack of studies examining the effect of parity and breastfeeding in a setting where all healthy mothers are recommended discharge four hours after birth. Therefore, this study examined the association between parity and the time for discharge, breastfeeding, and factors influencing breastfeeding. METHODS: The study was designed as a prospective cohort study. Data were obtained from questionnaires at one and at six weeks after birth, and combined with registered data. All 147 included mothers were healthy, with an uncomplicated birth and a healthy newborn, discharged within 24 hours after birth. RESULTS: This study documented that primiparous women had a higher relative risk (RR=2.62; 95% CI: 1.35-5.10) of having doubts about infant feeding after discharge than multiparous women. Furthermore, 54% of primiparous women contacted the maternity ward after discharge compared to 27% of multiparous women. Twice as many primiparous than multiparous women felt anxious or depressed at one and at six weeks after birth. Finally, the study documented that 13% of primiparous women and 5% of multiparous women discharged within six hours after birth perceived the time before discharge to be too short. CONCLUSIONS: Primiparous women differ from multiparous women regarding breastfeeding, insecurity, and anxiety. Special attention towards primiparous women and a follow-up strategy that allows the mothers to contact the maternity ward after early discharge is recommended.