A computational study to assess the pathogenicity of single or combinations of missense variants on respiratory complex I.

Variants found in the respiratory complex I (CI) subunit genes encoded by mitochondrial DNA can cause severe genetic diseases. However, it is difficult to establish a priori whether a single or a combination of CI variants may impact oxidative phosphorylation. Here we propose a computational approach based on coarse-grained molecular dynamics simulations aimed at investigating new CI variants. One of the primary CI variants associated with the Leber hereditary optic neuropathy (m.14484T>C/MT-ND6) was used as a test case and was investigated alone or in combination with two additional rare CI variants whose role remains uncertain. We found that the primary variant positioned in the E-channel region, which is fundamental for CI function, stiffens the enzyme dynamics. Moreover, a new mechanism for the transition between π- and α-conformation in the helix carrying the primary variant is proposed. This may have implications for the E-channel opening/closing mechanism. Finally, our findings show that one of the rare variants, located next to the primary one, further worsens the stiffening, while the other rare variant does not affect CI function. This approach may be extended to other variants candidate to exert a pathogenic impact on CI dynamics, or to investigate the interaction of multiple variants.

Fluorogenic Hyaluronan Nanogels Track Individual Early Protein Aggregates Originated under Oxidative Stress.

Proteins are broadly versatile biochemical materials, whose functionality is tightly related to their folding state. Native folding can be lost to yield misfolded conformations, often leading to formation of protein oligomers, aggregates, and biomolecular phase condensates. The fluorogenic hyaluronan HA-RB, a nonsulfonated glycosaminoglycan with a combination of polyanionic character and of hydrophobic spots due to rhodamine B dyes, binds to early aggregates of the model protein cytoplasmic glyceraldehyde-3-phosphate dehydrogenase 1 from Arabidopsis thaliana (AtGAPC1) since the very onset of the oligomeric phase, making them brightly fluorescent. This initial step of aggregation has, until now, remained elusive with other fluorescence- or scattering-based techniques. The information gathered from nanotracking (via light-sheet fluorescence microscopy) and from FCS in a confocal microscope converges to highlight the ability of HA-RB to bind protein aggregates from the very early steps of aggregation and with high affinity. Altogether, this fluorescence-based approach allows one to monitor and track individual early AtGAPC1 aggregates in the size range from 10 to 100 nm with high time (∼10-2 s) and space (∼250 nm) resolution.

Telemedicine in the treatment of gestational diabetes: An observational cohort study on pregnancy outcomes and maternal satisfaction.

AIMS: Gestational diabetes treatment requires several outpatient consultations from diagnosis until delivery in order to prevent hyperglycaemia, which is associated with maternal and fetal complications. There is limited evidence in the literature about telemedicine superiority in improving pregnancy outcomes for women with gestational diabetes. The primary aim of the study was to evaluate maternal and fetal outcomes, while the secondary aim was to estimate the degree of satisfaction with gestational diabetes treatment, comparing telemedicine versus outpatient care. METHODS: This observational cohort study involved 60 consecutive women with gestational diabetes treated at the Diabetology Unit of Ferrara: 27 were followed up through a weekly remote control method (telemedicine group) and 33 in ambulatory clinics every 2 or 3 weeks (conventional group). After giving birth, 56 women responded to the modified Oxford Maternity Diabetes Treatment Satisfaction Questionnaire to assess their satisfaction with diabetes care. RESULTS: No statistically significant differences were found in most of the maternal and neonatal parameters evaluated in both groups. The questionnaire scores were positive in all areas investigated. Telemedicine follow-up made women feel more controlled (p = 0.045) and fit better with their lifestyle (p = 0.005). It also emerged that almost all women treated with telemedicine would recommend this method to a relative or a friend. CONCLUSIONS: Telemedicine follow-up proved to be safe both in terms of metabolic control and pregnancy outcomes; furthermore, it significantly decreased the need for outpatient consultations and increased women's satisfaction. Studying the impact of telemedicine is also necessary, considering the current difficulties associated with the Sars-COV-2 pandemic.

Contrast enhanced ultrasound as a new tool to estimate the performance of midline catheters in the single patient.

BACKGROUND: Contrast enhanced ultrasound (CEUS) through MicroBubbles Time (MBT) (time from infusion of saline with addition of micro-bubbles of air to visualization of first bubbles in right atrium (RA), visualized by subxiphoid or apical echocardiography) is an alternative to Intracavitary ECG and chest X-ray in evaluation of tip location in central venous catheters. OBJECTIVE: To evaluate feasibility and variability of CEUS in peripheral catheters (Midline-MC) in a cohort of patients and in a subgroup where tip location was also performed through chest X-ray. Secondary outcomes were verifying the correlation between MBT and distance between tip of MC and RA (anthropometric and radiological measures), body mass index (BMI), vein diameter at point of insertion. METHODS: Patients with insertion of MC were enrolled in this prospective cohort. After catheter insertion, CEUS was performed recording MBT. RESULTS: One hundred thirty-two MCs were inserted, 45 performed Chest X-ray. MBT wasn't feasible in 7 (5%) because of low quality echocardiographic images. Subcostal view was available in 114 patients (91.2%), while 11 patients (8.8%) were examined through apical four-chamber view. Mean MBT in the whole population was 2.3 ± 0.8 s. Significant correlation between anthropometric and radiological measures, BMI and MBT was found. 32.8% of MC had a MBT ⩽2 s. CONCLUSIONS: CEUS could be useful to estimate tip position. Our study showed how 2 s is not a suitable cutoff to confirm central catheter's tip.

Midline peripheral catheters inserted in the superficial femoral vein at mid-thigh: Wise choice in COVID-19 acute hypoxemic respiratory failure patients with helmet continuous positive airway pressure.

BACKGROUND: During coronavirus disease 2019 (COVID-19) pandemic, Helmet Continuous Positive Airway Pressure (h-CPAP) has been widely used to treat Acute Hypoxemic Respiratory Failure (AHRF). In COVID-19 patients undergoing h-CPAP a simple short peripheral catheter could be insufficient. According to the European Recommendations for Proper Indication and Use of Peripheral venous access consensus, a stable peripheral Vascular Access Device is indicated for intravenous treatment compatible with the peripheral route scheduled for more than 1 week. OBJECTIVE: The aim of this prospective study was to evaluate the performance and the potential complications of superficial femoral midline catheters (SFMC) inserted in the Superficial Femoral Vein by direct Seldinger technique with peripheral tip (Arrow®, Teleflex; 20 cm length four FR single lumen and seven FR dual lumen) in AHRF COVID-19 patient. Complications were divided in early (accidental puncture of superficial femoral artery (APSFA); accidental saphenous nerve puncture (ASNP); bleeding) and late (Catheter Related Thrombosis (CRT); Catheter-Related Bloodstream Infections (CRBSI); Accidental Removal (AR); persistent withdrawal occlusion (PWO)). METHODS: From 1st October 2020 to 30th June 2021 we conducted a prospective observational study in COVID-19 sub-intensive wards at Luigi Sacco Hospital (Milan). RESULTS: Hundred seventy five SFMC (mean dwell time 11.1 ± 9.8 days) were implanted in COVID-19 patients, 107 (61.1%) during h-CPAP treatment (10.5 ± 8.9 days), the remaining 68 (38.9%) in patients with severe disease. We recorded two minor immediate/early complications (APSFA without sequelae) and no major complications.The long-term follow-up registered four CRBSI (2.3%-2.5/1000 catheters days (CD)), five CRT (2.9%: 2.6/1000 CD), 22 AR (12.6%; 11.4/1000 CD), 38 PWO (36.5%), 34 of which occurred due to fibroblastic sleeve (32.7%). CONCLUSIONS: SFMC proved to be safe, easy and time-saving. It could be implemented, after a careful benefits and risks evaluation, in particular settings such as h-CPAP, delirium, bleeding risk factors and palliative care patients.

Pulsed-wave Doppler for ultrasound-based tip location using bubble test: A pilot study.

BACKGROUND: MicroBubbles Time test (MBT), consisting in the rapid infusion of saline with addition of air microbubbles, visualized by B-mode echocardiography, represents a potential alternative to Intracavitary ECG (IC-ECG) and chest X-ray for central venous catheters (CVCs) tip location. Even if promising, this technique lacks of standardization: a clear time cut-off between bubble infusion and their detection in heart's right chambers hasn't been yet established. At these regard, microbubbles could be also detected as microembolic signals (MES) with an alternative ultrasound technique: the pulse wave Doppler (PW). OBJECTIVE AND METHODS: The first aim of this pilot study is to establish agreement of MBT with PW test (MBT-PW) compared with reference standard IC-ECG and normal MBT for tip location on CVCs. Corrected tip's position was established through reference standard IC-ECG, afterward MBT-PW was performed, with the sample volume placed at tricuspid valve to detect MES simultaneously with micro-bubbles injection in CVCs. The second aim was to evaluate inter-observer variability for MES detection and grading. RESULTS: Eight patients were enrolled; we obtained three records for each patients (24 with MBT and 24 with MBT-PW, the two techniques were acquired simultaneously). Inter-methods agreement through reference standard IC-ECG versus MBT-PW and MBT versus MBT-PW methodic was satisfying (Cohen's kappa value = 1). MBT-PW and MBT signals were recorded within the first heart beat after microbubble infusion in all patients. Mean time delay thorough MBT-PW and MBT was 0.76 ±0.07 and 0.78 ± 0.07 s respectively; Intraclass correlation coefficient was 0.992 (95% CI: 0.981-0.996) suggesting excellent correlation. Inter-observer variability for positive MBT-PW evaluation was optimal (Cohen's kappa value was 1), while indicated substantial agreement for MES grade evaluation (Fleiss' Kappa value was 0.704; 95% CI: 0.328-1.000). CONCLUSIONS: Our study supports agreement between MBT-PW and reference standard IC-ECG for tip location. Satisfactory agreement was observed also for MBT-PW and MBT.

Retrospective survey from vascular access team Lombardy net in COVID-19 era.

BACKGROUND: Venous Access Devices (VADs) are the most used devices in COVID-19 patients. OBJECTIVE: Identify VADs implanted, catheter related thrombosis (CRT), catheter-related bloodstream infection (CRBSI), and accidental remove of VADs in both COVID-19 positive and COVID-19 free patients. Successive analysis was conducted comparing COVID-19 positive patients with COVID-19 free with inverse probability propensity score weights using simple regression to account for these two confounders (peripheral tip as central/peripheral and hospitalization as no/yes). METHODS: This multicenter, retrospective cohort study collected data from seven hospitals in Lombardy during the pandemic period from February 21st to May 31st 2020. RESULTS: A total of 2206 VADs were evaluated, 1107 (50.2%) of which were inserted in COVID-19 patients. In COVID-19 cohort the first choice was Long Peripheral Cannula in 388 patients (35.1%) followed by Midline Catheter in 385 (34.8%). The number of "central tip" VADs inserted in COVID-free inpatients and COVID-19 positive were similar (307 vs 334). We recorded 42 (1.9%) CRT; 32 (79.2%) were observed in COVID-19 patients. A total of 19 CRBSI were diagnosed; 15 (78.95%) were observed in COVID-19. Accidental removals were the more represented complication with 123 cases, 85 (69.1%) of them were in COVID-19. COVID-19 significantly predicted occurrence of CRT (OR = 2.00(1.85-5.03); p < 0.001), CRSB (OR = 3.82(1.82-8.97); p < 0.001), and Accidental Removal (OR = 2.39(1.80-3.20); p < 0.001) in our propensity score weighted models. CONCLUSIONS: CRT, CRBSI, and accidental removal are significantly more frequent in COVID-19 patients. Accidental removals are the principal complication, for this reason, the use of subcutaneously anchored securement is recommended for a shorter period than usual.

Real-World Evaluation of Glycemic Outcomes and Extra-Glycemic Parameters in Diabetic Patients Treated with the Combined Formulation Degludec-Liraglutide (Ideglira).

INTRODUCTION: Combination therapy with both basal insulin (BI) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) is an effective treatment in patients with uncontrolled type 2 diabetes mellitus (T2DM). The recent development and release of a fixed-ratio combination of slow-release insulin degludec and the GLP-1RA liraglutide (IDegLira) represents an improvement to this therapy. We have conducted a real-world evidence study in Italian patients with T2DM to evaluate whether the encouraging clinical trial results obtained with IDegLira, which became available in Italy in January 2018, can be confirmed in Italian clinical practice. METHODS: This was a multicenter, retrospective, observational study in patients with T2DM treated with IDegLira from January to December 2018. Prior to the initiation of IDegLira therapy, patients were treated with BI with or without one or more concomitant oral antidiabetic drugs (BOT group) or according to the basal bolus protocol (BI and rapid-acting insulin treatment; BB group). RESULTS: A total of 244 patients were included in the present study, of whom 186 were in the BOT group and 58 in the BB group. Following the switch to IDegLira therapy, glycemic control improved in both groups, with significant reductions in glycated hemoglobin after 6 and 12 months of treatment in the BOT group and after 6 months of treatment in the BB group. No gain in body weight and body mass index and reductions in fasting plasma glucose and number of concomitant diabetic medications (in BOT patients) were observed. All results obtained during the study were achieved at a moderate dose of IDegLira. CONCLUSION: The findings from this study show that in a real-world setting, the switch to IDegLira treatment is a valid option for patients who are failing to achieve glycemic control targets and/or struggling with the side effects, such as weight gain and hypoglycemia, of other insulin therapies.

Conduction and Gating Properties of the TRAAK Channel from Molecular Dynamics Simulations with Different Force Fields.

In recent years, the K2P family of potassium channels has been the subject of intense research activity. Owing to the complex function and regulation of this family of ion channels, it is common practice to complement experimental findings with the atomistic description provided by computational approaches such as molecular dynamics (MD) simulations, especially, in light of the unprecedented timescales accessible at present. However, despite recent substantial improvements, the accuracy of MD simulations is still undermined by the intrinsic limitations of force fields. Here, we systematically assessed the performance of the most popular force fields employed to study ion channels at timescales that are orders of magnitude greater than the ones accessible when these energy functions were first developed. Using 32 µs of trajectories, we investigated the dynamics of a member of the K2P ion channel family, the TRAAK channel, using two established force fields in simulations of biological systems: AMBER and CHARMM. We found that while results are comparable on the nanosecond timescales, significant inconsistencies arise at microsecond timescales.

Tumour-infiltrating cytotoxic T lymphocytes in somatotroph pituitary neuroendocrine tumours.

INTRODUCTION: Somatotroph pituitary tumours are often resistant to first-generation somatostatin analogues and can invade the surrounding structures, limiting the chances of curative surgery. Recent studies suggested that the immune microenvironment and pro-angiogenic factors can influence neuroendocrine tumour prognosis. In this study, we aimed to investigate the prognostic role of immune cell-specific markers and endocan, a proteoglycan involved in neoangiogenesis and cell adhesion, in a cohort of acromegaly patients who underwent pituitary surgery as first-line treatment. SUBJECTS AND METHODS: Sixty four eligible subjects were identified. CD4+, CD8+ and CD68+ cells and endocan expression were evaluated by immunohistochemistry and results correlated with clinical and neuroradiological findings. Responsiveness to somatostatin analogues was assessed in patients with persistent disease following surgery. RESULTS: The number of CD8+ lymphocytes was significantly lower in tumours with cavernous sinus invasion (median 0.2/HPF, IQR: 2.2) compared with those without cavernous sinus invasion (median 2.4/HPF, IQR: 2.3; P = 0.04). Tumours resistant to first-generation somatostatin analogues had lower CD8+ lymphocytes (median 1/HPF, IQR: 2.4) compared with responders (median 2.4/HPF, IQR: 2.9; P = 0.005). CD4+ lymphocytes were observed sporadically. The number of CD68+ macrophages and the endothelial or tumour cell endocan expression did not differ based on tumour size, cavernous sinus invasion or treatment responsiveness. CONCLUSIONS: Our study suggests that a lower number of CD8+ lymphocytes is associated with cavernous sinus invasion and resistance to treatment with first-generation somatostatin analogues in acromegaly patients. These results highlight a potential role of the tumour immune microenvironment in determining the prognosis of somatotroph pituitary tumours.

Modeling Living Cells Response to Surface Tension and Chemical Patterns.

Mechanobiology is an important epigenetic factor. It influences cell functioning and bears on gene induction, protein synthesis, cell growth, and differentiation. In the presence of patterned chemical cues, living cells can take shapes that are far from that of a drop of fluid. These shapes are characterized by inward curvatures that are pinned at the points of location of the cues. The mechanochemical interactions that orchestrate cell behavior is simulated and controlled by modeling the cells as made by parcels of fluid. Cells become drops that are then endowed with the presence of additional forces, generated on the fly, that effectively make them active. With the proper choice of the forces, the phenomena that emerge from the dynamics match quantitatively the experiments. A combination of hydrophilic and lipophilic forces acting between the beads of fluid allows the active drop to respond to patterned cues and form squares, pentagons, hexagons, and flowers, just as living cells do.

"Active" drops as phantom models for living cells: a mesoscopic particle-based approach.

Drops and biological cells share some morphological features and visco-elastic properties. The modelling of drops by mesoscopic non-atomistic models has been carried out to a high degree of success in recent years. We extend such treatment and discuss a simple, drop-like model to describe the interactions of the outer layer of cells with the surfaces of materials. Cells are treated as active mechanical objects that are able to generate adhesion forces. They appear with their true size and are made of "parcels of fluids" or beads. The beads are described by (very) few quantities/parameters related to fundamental chemical forces such as hydrophilicity and lipophilicity that represent an average of the properties of a patch of material or an area of the cell(s) surface. The investigation of adhesion dynamics, motion of individual cells, and the collective behavior of clusters of cells on materials is possible. In the simulations, the drops become active soft matter objects and different from regular droplets they do not fuse when in contact, their trajectories are not Brownian, and they can be forced "to secrete" molecules, to name some of the properties targeted by the modeling. The behavior that emerges from the simulations allows ascribing some cell properties to their mechanics, which are related to their biological features.

Factors predicting pasireotide responsiveness in somatotroph pituitary adenomas resistant to first-generation somatostatin analogues: an immunohistochemical study.

AIM: To gather data regarding factors predicting responsiveness to pasireotide in acromegaly. PATIENTS AND METHODS: SSTR2a, SSTR3, SSTR5, AIP, Ki-67 and the adenoma subtype were evaluated in somatotroph adenomas from 39 patients treated post-operatively with somatostatin analogues (SSAs). A standardized SSTR scoring system was applied (scores 0-3). All patients received first-generation SSAs, and 11 resistant patients were subsequently treated with pasireotide LAR. RESULTS: None of the patients with negative or cytoplasmic-only SSTR2a expression (scores 0-1) were responsive to first-generation SSAs, as opposed to 20% (score 2) and 50% of patients with a score of 3 (P=0.04). None of the patients with an SSTR5 score of 0-1 were responsive to pasireotide, as opposed to 5/7 cases with a score of 2 or 3 (P=0.02). SSTR3 expression did not influence first-generation SSAs or pasireotide responsiveness. Tumours with low AIP were resistant to first-generation SSAs (100 vs 60%; P=0.02), while they had similar responsiveness to pasireotide compared to tumours with conserved AIP expression (50 vs 40%; P=0.74). Tumours with low AIP displayed reduced SSTR2 (SSTR2a scores 0-1 44.4 vs 6.7%; P=0.006) while no difference was seen in SSTR5 (SSTR5 scores 0-1 33.3 vs 23.3%; P=0.55). Sparsely granulated adenomas responded better to pasireotide compared to densely granulated ones (80 vs 16.7%; P=0.04). CONCLUSION: The expression of SSTR5 might predict responsiveness to pasireotide in acromegaly. AIP deficient and sparsely granulated adenomas may benefit from pasireotide treatment. These results need to be confirmed in larger series of pasireotide-treated patients.

Electrochemical fabrication of surface chemical gradients in thiol self-assembled monolayers with tailored work-functions.

The studies on surface chemical gradients are constantly gaining interest both for fundamental studies and for technological implications in materials science, nanofluidics, dewetting, and biological systems. Here we report on a new approach that is very simple and very efficient, to fabricate surface chemical gradients of alkanethiols, which combines electrochemical desorption/partial readsorption, with the withdrawal of the surface from the solution. The gradient is then stabilized by adding a complementary thiol terminated with a hydroxyl group with a chain length comparable to desorbed thiols. This procedure allows us to fabricate a chemical gradient of the wetting properties and the substrate work-function along a few centimeters with a gradient slope higher than 5°/cm. Samples were characterized by cyclic voltammetry during desorption, static contact angle, XPS analysis, and Kelvin probe. Computer simulations based on the Dissipative Particle Dynamics methods were carried out considering a water droplet on a mixed SAM surface. The results help to rationalize the composition of the chemical gradient at different position on the Au surface.

Real-world study of everolimus in advanced progressive neuroendocrine tumors.

Everolimus is a valid therapeutic option for neuroendocrine tumors (NETs); however, data in a real-world setting outside regulatory trials are sparse. The aim of this study was to determine everolimus tolerability and efficacy, in relation to previous treatments, in a compassionate use program. A total of 169 patients with advanced progressive NETs treated with everolimus were enrolled, including 85 with pancreatic NETs (pNETs) and 84 with nonpancreatic NETs (non-pNETs). Previous treatments included somatostatin analogs (92.9%), peptide receptor radionuclide therapy (PRRT; 50.3%), chemotherapy (49.7%), and PRRT and chemotherapy (22.8%). Overall, 85.2% of patients experienced adverse events (AEs), which were severe (grade 3-4) in 46.1%. The most frequent severe AEs were pneumonitis (8.3%), thrombocytopenia (7.7%), anemia (5.3%), and renal failure (3.5%). In patients previously treated with PRRT and chemotherapy, a 12-fold increased risk for severe toxicity was observed, with grade 3-4 AEs reported in 86.8% (vs. 34.3% in other patients). In addition, 63.3% of patients required temporarily everolimus discontinuation due to toxicity. Overall, 27.8% of patients died during a median follow-up of 12 months. Median progression-free survival (PFS) and overall survival (OS) were 12 months and 32 months, respectively. Similar disease control rates, PFS, and OS were reported in pNETs and non-pNETs. In the real-world setting, everolimus is safe and effective for the treatment of NETs of different origins. Higher severe toxicity occurred in patients previously treated with systemic chemotherapy and PRRT. This finding prompts caution when using this drug in pretreated patients and raises the issue of planning for everolimus before PRRT and chemotherapy in the therapeutic algorithm for advanced NETs.

Ki-67 grading of nonfunctioning pancreatic neuroendocrine tumors on histologic samples obtained by EUS-guided fine-needle tissue acquisition: a prospective study.

BACKGROUND: Preoperative determination of Ki-67 expression, an important prognostic factor for grading nonfunctioning pancreatic endocrine tumors (NF-PETs), remains an important clinical challenge. OBJECTIVE: To prospectively evaluate the feasibility, yield, and clinical impact of EUS-guided fine-needle tissue acquisition (EUS-FNTA) with a large-gauge needle to obtain tissue samples for histologic diagnosis and Ki-67 analysis in patients with suspected NF-PETs. DESIGN: Prospective cohort study. SETTING: Tertiary-care academic medical center. PATIENTS: Consecutive patients with a single pancreatic lesion suspicious for NF-PET on imaging. INTERVENTION: EUS-FNTA with a 19-gauge needle. MAIN OUTCOME MEASUREMENTS: Feasibility and yield of EUS-FNTA for diagnosis and Ki-67 expression determination. RESULTS: Thirty patients (mean [± SD] age 55.7 ± 14.9 years), with a mean (± SD) lesion size of 16.9 ± 6.1 mm were enrolled. EUS-FNTA was successfully performed without complications in all patients, with a mean (± SD) of 2.7 ± 0.5 passes per patient. Adequate samples for histologic examination were obtained in 28 of the 30 patients (93.3%). Ki-67 determination could be performed in 26 of these 28 patients (92.9%, 86.6% overall), 12 of whom underwent surgical resection. Preoperative and postoperative Ki-67 proliferation indexes were concordant in 10 patients (83.3%), whereas 2 patients were upstaged from G1 to G2 or downstaged from G2 to G1, respectively. LIMITATIONS: Single center study with a single operator. CONCLUSION: In patients with suspected nonfunctioning low-grade to intermediate-grade pancreatic neuroendocrine tumors (p-NETs), retrieval of tissue specimens with EUS-FNTA by using a 19-gauge needle is safe, feasible, and highly accurate for both diagnosis and Ki-67 determination. A Ki-67 proliferative index acquired through this technique might be of great help for further therapeutic decisions.

Amyloid-ß fibril disruption by C60-molecular guidance for rational drug design.

The WHO has listed Alzheimer's disease among the major neurological disorders with an estimated 35 million people affected worldwide. Amyloid-ß is mostly believed to be the causative factor in Alzheimer's disease and the severity of the disease correlates with the tendency of amyloid-ß to form aggregation patterns-plaques. Lacking effective medication, the identification of any underlying mechanistic principles regarding plaque formation appears to be crucial. Here we carry out computer simulations to study the effect of C60 on structure and stability of an idealised pentameric construct of amyloid-ß units (a model fibril). A binding site on top of the structurally ordered stack of ß-sheets is identified that triggers structural alterations at the turn region of the hook-like ß-sheet assembly. Significant structural alterations are: (i) the destruction of regular helical twist, (ii) the loss of a stabilizing salt bridge and (iii) the loss of a stabilizing hydrophobic interaction close to the turn. Consequently, the main effect of C60 is the induction of sizable destabilization in native fibril structure. These structural insights may serve as a molecular guide for further rational drug design of effective inhibitors targeting fibril formation in Alzheimer's disease.

Treatment with octreotide LAR in clinically non-functioning pituitary adenoma: results from a case-control study.

Surgical cure cannot be achieved in most patients with invasive non-functioning pituitary macroadenoma (NFPA). Short-term residual tumor treatment with somatostatin analogs has produced disappointing results. This prospective case-control study assessed the efficacy of chronic treatment with long acting octreotide (octreotide LAR) on tumor volume in patients harboring post-surgical NFPA residue. The study population comprised 39 patients with NFPAs not cured by surgery. All patients underwent somatostatin receptor scintigraphy at least 6 months after the last surgery. Patients with a positive pituitary level octreoscan at (n = 26) received octreotide LAR (20 mg every 28 days) for ≥ 12 months (mean follow-up 37 ± 18 months) (Treated group). Moreover, a fragment of tumor tissue from patients in the treated group was retrospectively collected to assess the immunohistochemical expression of somatostatin receptor subtypes (SSTRs). The patients with a negative octreoscan (n = 13) formed the control group (mean follow-up 37 ± 16 months). Hormonal, radiological and visual field parameters were periodically assessed. In the treated group, all tumors expressed at least one SSTR subtype. The SSTR5 subtype was the most abundant, followed by SSTR3. The tumor residue increased in five of 26 patients (19%) in the treated group and in seven of 13 controls (53%). Visual field and pituitary function did not change in any patient. This study indicates that SSTR5 and SSTR3 are the most frequently expressed SSTR subtypes in NFPAs and supports a potential role of SSTR subtypes in stabilization of tumor remnant from NFPAs.