Development of a large diameter in vitro flow loop thrombogenicity test system.

BACKGROUND: To accommodate a wider range of medical device sizes, a larger in vitro flow loop thrombogenicity test system using 9.5 -mm inner diameter (ID) tubing was developed and evaluated based on our previously established 6.4 -mm ID tubing system. METHODS: Four cardiopulmonary bypass roller pumps were used concurrently to drive four flow loops during testing. To ensure that each pump produced a consistent thrombogenic response for the same material under the same test conditions, a novel dynamic roller occlusion setting method was applied. Five materials with varying thrombogenic potentials were tested: polytetrafluoroethylene (PTFE), silicone, 3D-printed nylon, latex, and nitrile rubber (BUNA). Day-old bovine blood was heparinized to a donor-specific concentration and recirculated through the flow loops containing test materials at 20 rpm for 1 h at room temperature. Material thrombogenicity was characterized by measuring the thrombus surface coverage, thrombus weight, and platelet (PLT) count reduction. RESULTS: The larger tubing system can differentiate thrombogenic materials (latex, BUNA) from the thromboresistant PTFE material. Additionally, silicone and the 3D-printed nylon exhibited an intermediate thrombogenic response with significantly less thrombus surface coverage and PLT count reduction than latex and BUNA but more thrombus surface coverage than PTFE (p < 0.05). CONCLUSION: The 9.5 -mm ID test system can effectively differentiate materials of varying thrombogenic potentials when appropriate pump occlusion settings and donor-specific anticoagulation are used. This system is being assessed in an interlaboratory study to develop standardized best practices for performing in vitro dynamic thrombogenicity testing of medical devices and materials.

Extensive antimicrobial resistance mobilization via multicopy plasmid encapsidation mediated by temperate phages.

OBJECTIVES: To investigate the relevance of multicopy plasmids in antimicrobial resistance and assess their mobilization mediated by phage particles. METHODS: Several databases with complete sequences of plasmids and annotated genes were analysed. The 16S methyltransferase gene armA conferring high-level aminoglycoside resistance was used as a marker in eight different plasmids, from different incompatibility groups, and with differing sizes and plasmid copy numbers. All plasmids were transformed into Escherichia coli bearing one of four different lysogenic phages. Upon induction, encapsidation of armA in phage particles was evaluated using qRT-PCR and Southern blotting. RESULTS: Multicopy plasmids carry a vast set of emerging clinically important antimicrobial resistance genes. However, 60% of these plasmids do not bear mobility (MOB) genes. When carried on these multicopy plasmids, mobilization of a marker gene armA into phage capsids was up to 10000 times more frequent than when it was encoded by a large plasmid with a low copy number. CONCLUSIONS: Multicopy plasmids and phages, two major mobile genetic elements (MGE) in bacteria, represent a novel high-efficiency transmission route of antimicrobial resistance genes that deserves further investigation.

Reply: "Percutaneously guided or ultrasound-guided splenic punctures are safe procedures with a high diagnostic performance".

We appreciate the interest shown in our article "Endoscopic ultrasound-guided fine-needle aspiration for splenomegaly and focal splenic lesion: is it safe, effective and necessary?", as well as the academic discussion raised by gastroenterology-ultrasound experts in the letter to the editor. In the discussion of our article, we mention that EUS-FNA is necessary and/or the first option in splenomegaly and/or small focal splenic lesions where percutaneous biopsy are limited, when difficulty accessing the focal splenic lesions, in obese patients and in those with ascites, recent abdominal surgery or a poor acoustic window.

Role of Full-spectrum Endoscopy in Colorectal Cancer Screening: Randomized Trial.

GOALS: The aim of this study was to compare a new, full-spectrum endoscope (Fuse; EndoChoice, Alpharetta, GA) to standard forward-viewing colonoscopy in the detection of colorectal neoplasms. BACKGROUND: Colonoscopy, the gold standard for the detection of colorectal cancer, fails to detect 22% to 28% of polyps, increasing the risk of interval cancer. Endoscopic improvement of the adenoma detection rate decrease interval carcinomas. Full-spectrum endoscopy (FUSE) (330-degree field of view), in a tandem study, has been shown to reduce the adenoma miss rate. STUDY: Prospective, randomized study of 249 patients in patients referred from the colorectal screening program with a positive fecal occult blood test (FOBT). Patients were randomized to standard forward-viewing colonoscopy (170 degrees) or to full-spectrum colonoscopy with the Fuse system (330 degrees). Study variables were the adenoma detection rate, the polyp detection rate, the mean number of adenomas per procedure, the lesions detected according to the location, morphology and size, cecal intubation rate, total procedure time, insertion time to the cecum, therapeutic success, and adverse events. RESULTS: The Fuse system did not produce a significantly higher adenoma detection rate than standard forward-viewing colonoscopy (FUSE 73.1% vs. standard colonoscopy 68.1%; P=0.47) but did have a significantly longer insertion time (FUSE 6.2 min vs. standard colonoscopy 4.2 min; P< 0.001). Further analysis failed to reveal any significant difference in polyp/adenoma detection rates by lesion size or colonic section. CONCLUSIONS: FUSE did not detect significantly more colorectal neoplasia than forward viewing colonoscopy in a medium-risk CRC screening population with positive FOBT.

Pituitary pathology in traumatic brain injury: a review.

PURPOSE: Traumatic brain injury most commonly affects young adults under the age of 35 and frequently results in reduced quality of life, disability, and death. In long-term survivors, hypopituitarism is a common complication. RESULTS: Pituitary dysfunction occurs in approximately 20-40% of patients diagnosed with moderate and severe traumatic brain injury giving rise to growth hormone deficiency, hypogonadism, hypothyroidism, hypocortisolism, and central diabetes insipidus. Varying degrees of hypopituitarism have been identified in patients during both the acute and chronic phase. Anterior pituitary hormone deficiency has been shown to cause morbidity and increase mortality in TBI patients, already encumbered by other complications. Hypopituitarism after childhood traumatic brain injury may cause treatable morbidity in those survivors. Prospective studies indicate that the incidence rate of hypopituitarism may be ten-fold higher than assumed; factors altering reports include case definition, geographic location, variable hospital coding, and lost notes. While the precise pathophysiology of post traumatic hypopituitarism has not yet been elucidated, it has been hypothesized that, apart from the primary mechanical event, secondary insults such as hypotension, hypoxia, increased intracranial pressure, as well as changes in cerebral flow and metabolism may contribute to hypothalamic-pituitary damage. A number of mechanisms have been proposed to clarify the causes of primary mechanical events giving rise to ischemic adenohypophysial infarction and the ensuing development of hypopituitarism. CONCLUSION: Future research should focus more on experimental and clinical studies to elucidate the exact mechanisms behind post-traumatic pituitary damage. The use of preventive medical measures to limit possible damage in the pituitary gland and hypothalamic pituitary axis in order to maintain or re-establish near normal physiologic functions are crucial to minimize the effects of TBI.

Endoscopic ultrasound-guided gallbladder drainage reduces adverse events compared with percutaneous cholecystostomy in patients who are unfit for cholecystectomy.

Background and study aim There are no data comparing endoscopic ultrasound (EUS)-guided gallbladder drainage (EGBD) with percutaneous cholecystostomy as a treatment for patients with acute cholecystitis. Patients and methods This was a 1 : 1 matched cohort study of all patients who were unfit for cholecystectomy and underwent EGBD or percutaneous cholecystostomy instead for the treatment of acute cholecystitis. The outcomes were matched for age, sex, and American Society of Anesthesiologists grade. Outcome measures included the technical and clinical success rates, adverse events, hospital stay, the number of unplanned admissions, and mortality. Results Between November 2011 and August 2014, a total of 118 patients were included in the study (59 EGBD, 59 percutaneous cholecystostomy). Technical and clinical success rates were similar. In the EGBD group, significantly fewer patients suffered from overall adverse events (19 [32.2 %] vs. 44 [74.6 %]; P < 0.001) and serious adverse events (14 [23.7 %] vs. 44 [74.6 %]; P < 0.001) compared to the percutaneous cholecystostomy group. Patients in the EGBD group required fewer unplanned admissions (4 [6.8 %] vs. 42 [71.2 %]; P < 0.001), which were due to problems related to the cholecystostomy tube in 95.2 %. The 30-day adverse event rates were similar between the groups (17 [28.8 %] vs. 10 [16.9 %]; P = 0.13). For instance, recurrent acute cholecystitis occurred in 0 patients in the EGBD group and in 4 (6.8 %) patients in the percutaneous cholecystostomy group (P = 0.12). The 30-day mortality rates were non-significantly higher in the EGBD group (5 [8.5 %] vs. 1 [1.7 %]; P = 0.21). Conclusions EGBD and percutaneous cholecystostomy were both effective means of achieving gallbladder drainage. EGBD may be a promising alternative to percutaneous cholecystostomy for treatment of acute cholecystitis in patients who are unfit for surgery, provided that experienced endosonographers are available.

Pathology of GH-producing pituitary adenomas and GH cell hyperplasia of the pituitary.

INTRODUCTION: Histologic, immunohistochemical and electron microscopic studies have provided conclusive evidence that a marked diversity exists between tumors which secrete growth hormone (GH) in excess. GH cell hyperplasia can also be associated with acromegaly in patients with extrapituitary GH-releasing hormone secreting tumors or in familial pituitary tumor syndromes. MATERIALS AND METHODS: A literature search was performed for information regarding pathology, GH-producing tumors and acromegaly. RESULTS: This review summarizes the current knowledge on the morphology of GH-producing and silent GH adenomas, as well as GH hyperplasia of the pituitary. CONCLUSION: The importance of morphologic classification and identification of different subgroups of patients with GH-producing adenomas and their impact on clinical management is discussed.

Evaluation of the short- and long-term effectiveness and safety of fully covered self-expandable metal stents for drainage of pancreatic fluid collections: results of a Spanish nationwide registry.

BACKGROUND AND AIMS: Initial reports suggest that fully covered self-expandable metal stents (FCSEMSs) may be better suited for drainage of dense pancreatic fluid collections (PFCs), such as walled-off pancreatic necrosis. The primary aim was to analyze the effectiveness and safety of FCSEMSs for drainage of different types of PFCs in a large cohort. The secondary aim was to investigate which type of FCSEMS is superior. METHODS: This was a retrospective, noncomparative review of a nationwide database involving all hospitals in Spain performing EUS-guided PFC drainage. From April 2008 to August 2013, all patients undergoing PFC drainage with an FCSEMS were included in a database. The main outcome measurements were technical success, short-term (2 weeks) and long-term (6 months) effectiveness, adverse events, and need for surgery. RESULTS: The study included 211 patients (pseudocyst/walled-off pancreatic necrosis, 53%/47%). The FCSEMSs used were straight biliary (66%) or lumen-apposing (34%). Technical success was achieved in 97% of patients (95% confidence interval [CI], 93%-99%). Short-term- and long-term clinical success was obtained in 94% (95% CI, 89%-97%) and 85% (95% CI, 79%-89%) of patients, respectively. Adverse events occurred in 21% of patients (95% CI, 16%-27%): infection (11%), bleeding (7%), and stent migration and/or perforation (3%). By multivariate analysis, patient age (>58 years) and previous failed drainage were the most important factors associated with negative outcome. CONCLUSIONS: An FCSEMS is effective and safe for PFC drainage. Older patients with a history of unsuccessful drainage are more likely to fail EUS-guided drainage. The type of FCSEMS does not seem to influence patient outcome.

Endoscopic ultrasound-assisted bile duct access and drainage: multicenter, long-term analysis of approach, outcomes, and complications of a technique in evolution.

BACKGROUND AND STUDY AIMS: When endoscopic retrograde cholangio-pancreatography fails, the bile duct is drained percutaneously or surgically. Evolution of endoscopic ultrasound (EUS) has provided the ability to visualize and also drain the biliary tree. The aim of this study was to review different techniques of EUS-guided bile duct access and drainage, and compare extrahepatic (EH) and intrahepatic (IH) approaches and benign with malignant indications. PATIENTS AND METHODS: EUS-guided attempts at bile duct drainage from 6 international centers were reviewed. This is a multicenter, nonrandomized retrospective study. RESULTS: Two hundred forty patients underwent EUS-guided bile duct access and drainage (EUS-BD) with a mean age of 67.3 years. The IH approach was used in 60% of the cases. In 99% of the subjects, a 19-G needle was used. Success was achieved in 87% cases, with a similar success rate in EH and IH approaches (84.3% vs. 90.4%; P=0.15). Metal stents were placed in 60% and plastic stents in 27% of the cases. A higher success rate was noted in malignant diseases compared with benign diseases (90.2% vs. 77.3%; P=0.02). Complications for all techniques included pneumoperitoneum 5%, bleeding 11%, bile leak/peritonitis 10%, and cholangitis 5%. No significant difference was noted between the IH and the EH approaches (32.6% vs. 35.6%; P=0.64), with similar rates in benign and malignant diseases (26.7% vs. 37.1%; P=0.19). CONCLUSIONS: The EUS-BD technique is currently limited by a lack of dedicated devices and large data reporting outcomes and complications. Larger prospective and multicenter studies are needed to better define the indications, outcomes, and complications. With greater experience and dedicated devices, EUS-BD can be an effective alternative.

Proprioception and Control of a Soft Pneumatic Actuator Made of a Self-Healable Hydrogel.

The current evolutionary trends in soft robotics try to exploit the capacities of smart materials to achieve compact robotics designs with embodied intelligence. In this way, the number of elements that compose the soft robot can be reduced, as the smart material can cover different aspects (e.g., structure and sensorization) all in one. This work follows this tendency and presents a custom-designed hydrogel that exhibits two smart features, self-healing and ionic conductivity, used to build a pneumatic actuator. The self-healing capability provides the actuator's structure with the ability to self-repair from damages (e.g., punctures or cuts), an important quality to prolong the life cycle of the actuator. The ionic conductivity enables the actuator's proprioception: the structure itself serves as a curvature sensor. The behavior of this proprioceptive curvature sensor is analyzed in this work, studying its linearity, stability, and performance after a self-healing process. This sensor is also proposed as feedback in a closed-loop scheme to automatically control the actuator's curvature. A proportional-integral-derivative controller is designed based on an empirical model of the actuator's dynamics, and then validated in experimental tests, proving the proprioceptive sensor as proper feedback. These control tests are performed over undamaged and self-healed actuators, thus demonstrating all the capabilities of our soft material.

Incorporation of decellularized-ECM in graphene-based scaffolds enhances axonal outgrowth and branching in neuro-muscular co-cultures.

Peripheral nerve and large-scale muscle injuries result in significant disability, necessitating the development of biomaterials that can restore functional deficits by promoting tissue regrowth in an electroactive environment. Among these materials, graphene is favored for its high conductivity, but its low bioactivity requires enhancement through biomimetic components. In this study, we extrusion printed graphene-poly(lactide-co-glycolide) (graphene) lattice scaffolds, aiming to increase bioactivity by incorporating decellularized extracellular matrix (dECM) derived from mouse pup skeletal muscle. We first evaluated these scaffolds using human-induced pluripotent stem cell (hiPSC)-derived motor neurons co-cultured with supportive glia, observing significant improvements in axon outgrowth. Next, we tested the scaffolds with C2C12 mouse and human primary myoblasts, finding no significant differences in myotube formation between dECM-graphene and graphene scaffolds. Finally, using a more complex hiPSC-derived 3D motor neuron spheroid model co-cultured with human myoblasts, we demonstrated that dECM-graphene scaffolds significantly improved axonal expansion towards peripheral myoblasts and increased axonal network density compared to graphene-only scaffolds. Features of early neuromuscular junction formation were identified near neuromuscular interfaces in both scaffold types. These findings suggest that dECM-graphene scaffolds are promising candidates for enhancing neuromuscular regeneration, offering robust support for the growth and development of diverse neuromuscular tissues.

Critical systolic blood pressure threshold for endovascular aortic occlusion-A multinational analysis to determine when to place a REBOA.

BACKGROUND: Systolic blood pressure (SBP) is a potential indicator that could guide when to use a resuscitative endovascular balloon occlusion of the aorta (REBOA) in trauma patients with life-threatening injuries. This study aims to determine the optimal SBP threshold for REBOA placement by analyzing the association between SBP pre-REBOA and 24-hour mortality in severely injured hemodynamically unstable trauma patients. METHODS: We performed a pooled analysis of the aortic balloon occlusion (ABO) trauma and AORTA registries. These databases record the details related to the use of REBOA and include data from 14 countries worldwide. We included patients who had suffered penetrating and/or blunt trauma. Patients who arrived at the hospital with a SBP pre-REBOA of 0 mm Hg and remained at 0 mm Hg after balloon inflation were excluded. We evaluated the impact that SBP pre-REBOA had on the probability of death in the first 24 hours. RESULTS: A total of 1,107 patients underwent endovascular aortic occlusion, of these, 848 met inclusion criteria. The median age was 44 years (interquartile range [IQR], 27-59 years) and 643 (76%) were male. The median injury severity score was 34 (IQR, 25-45). The median SBP pre-REBOA was 65 mm Hg (IQR, 49-88 mm Hg). Mortality at 24 hours was reported in 279 (32%) patients. Math modeling shows that predicted probabilities of the primary outcome increased steadily in SBP pre-REBOA below 100 mm Hg. Multivariable mixed-effects analysis shows that when SBP pre-REBOA was lower than 60 mm Hg, the risk of death was more than 50% (relative risk, 1.5; 95% confidence interval, 1.17-1.92; p = 0.001). DISCUSSION: In patients who do not respond to initial resuscitation, the use of REBOA in SBPs between 60 mm Hg and 80 mm Hg may be a useful tool in resuscitation efforts before further decompensation or complete cardiovascular collapse. The findings from our study are clinically important as a first step in identifying candidates for REBOA. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level IV.

Ordered ferrimagnetic form of ferrihydrite reveals links among structure, composition, and magnetism.

The natural nanomineral ferrihydrite is an important component of many environmental and soil systems and has been implicated as the inorganic core of ferritin in biological systems. Knowledge of its basic structure, composition, and extent of structural disorder is essential for understanding its reactivity, stability, and magnetic behavior, as well as changes in these properties during aging. Here we investigate compositional, structural, and magnetic changes that occur upon aging of "2-line" ferrihydrite in the presence of adsorbed citrate at elevated temperature. Whereas aging under these conditions ultimately results in the formation of hematite, analysis of the atomic pair distribution function and complementary physicochemical and magnetic data indicate formation of an intermediate ferrihydrite phase of larger particle size with few defects, more structural relaxation and electron spin ordering, and pronounced ferrimagnetism relative to its disordered ferrihydrite precursor. Our results represent an important conceptual advance in understanding the nature of structural disorder in ferrihydrite and its relation to the magnetic structure and also serve to validate a controversial, recently proposed structural model for this phase. In addition, the pathway we identify for forming ferrimagnetic ferrihydrite potentially explains the magnetic enhancement that typically precedes formation of hematite in aerobic soil and weathering environments. Such magnetic enhancement has been attributed to the formation of poorly understood, nano-sized ferrimagnets from a ferrihydrite precursor. Whereas elevated temperatures drive the transformation on timescales feasible for laboratory studies, our results also suggest that ferrimagnetic ferrihydrite could form naturally at ambient temperature given sufficient time.

Genotypic Comparison of Pasteurella multocida from Healthy Animals at Entry to the Feedlots with That and from Bovine Respiratory Disease-Affected Animals during the Fattening Period.

The aim of this study was to investigate the possible genotypic differences between commensal Pasteurella multocida isolates from apparently healthy animals (AHA) at the time of entry to feedlots and those from BRD-affected animals (BRD-AA). A total of 20 batches of beef calves in seven feedlots were followed-up during the fattening period. P. multocida was isolated from 28.1% of AHA and 22.9% of BRD-AA. All isolates belonged to the A: L3 genotype. Most isolates from clinical cases (81.0%) grouped into a PFGE cluster were significantly associated with BRD cases (OR, 24.9; 95% CI, 6.4-96.2). The whole genomes of 14 isolates representative of the pulsotypes most frequently detected in BRD-AA and AHA were sequenced and compared with 53 bovine genomes belonging to the identified ST13, ST79, and ST80 genotypes for a global comparison. No differences were found in the virulence-associated gene content between sequence types (STs) globally or between BRD-AA and AHA isolates in this study. Significantly, ST79 isolates harbored ARGs, conferring resistance to different antimicrobials, including macrolides and tetracyclines, which are commonly used for the treatment of BRD. Two Spanish ST79 isolates carried an ICE highly similar to ICE Tn7407, which was recently detected in Germany, suggesting that ST79 P. multocida isolates in Europe and North America may be associated with different ICEs.

Isolation and genome sequence annotation of SallyK, a newly discovered cluster EG bacteriophage infecting Microbacterium.

Discovered from soil in a flower planter in Pocatello, Idaho and using Microbacterium foliorum, SallyK is a lytic bacteriophage with a siphovirus morphology. It has a 62,883 bp-long genome with 103 putative genes. Based on gene content similarity to actinobacteriophages, SallyK is assigned to cluster EG.

Isolation and genome sequence annotation of KillerTomato, a newly discovered cluster EE bacteriophage infecting Microbacterium.

Discovered in Pocatello, Idaho, soil near a tomato garden, siphovirus KillerTomato infects Microbacterium foliorum NRRL B-24224. KillerTomato is a lytic cluster EE phage with a 17,442-bp genome and 68.6% GC content. Of 25 genes, 20 were assigned putative functions, including a putative tail assembly chaperone protein with a programmed frameshift and an endolysin.

Global scenario of the RmtE pan-aminoglycoside-resistance mechanism: emergence of the rmtE4 gene in South America associated with a hospital-related IncL plasmid.

Antimicrobial resistance (AMR) mechanisms, especially those conferring resistance to critically important antibiotics, are a great concern for public health. 16S rRNA methyltransferases (16S-RMTases) abolish the effectiveness of most clinically used aminoglycosides, but some of them are considered sporadic, such as RmtE. The main goals of this work were the genomic analysis of bacteria producing 16S-RMTases from a 'One Health' perspective in Venezuela, and the study of the epidemiological and evolutionary scenario of RmtE variants and their related mobile genetic elements (MGEs) worldwide. A total of 21 samples were collected in 2014 from different animal and environmental sources in the Cumaná region (Venezuela). Highly aminoglycoside-resistant Enterobacteriaceae isolates were selected, identified and screened for 16S-RMTase genes. Illumina and Nanopore whole-genome sequencing data were combined to obtain hybrid assemblies and analyse their sequence type, resistome, plasmidome and pan-genome. Genomic collections of rmtE variants and their associated MGEs were generated to perform epidemiological and phylogenetic analyses. A single 16S-RMTase, the novel RmtE4, was identified in five Klebsiella isolates from wastewater samples of Cumaná. This variant possessed three amino acid modifications with respect to RmtE1-3 (Asn152Asp, Val216Ile and Lys267Ile), representing the most genetic distant among all known and novel variants described in this work, and the second most prevalent. rmtE variants were globally spread, and their geographical distribution was determined by the associated MGEs and the carrying bacterial species. Thus, rmtE4 was found to be confined to Klebsiella isolates from South America, where it was closely related to ISVsa3 and an uncommon IncL plasmid related with hospital environments. This work uncovered the global scenario of RmtE and the existence of RmtE4, which could potentially emerge from South America. Surveillance and control measures should be developed based on these findings in order to prevent the dissemination of this AMR mechanism and preserve public health worldwide.

Initial experience with EUS-guided cholangiopancreatography for biliary and pancreatic duct drainage: a Spanish national survey.

BACKGROUND: EUS-guided cholangiopancreatography (ESCP) allows transmural access to biliopancreatic ducts when ERCP fails. Data regarding technical details, safety, and outcomes of ESCP are still unknown. OBJECTIVE: To evaluate outcomes of ESCP in community and referral centers at the initial development phase of this procedure, to identify the ESCP stages with higher risk of failure, and to evaluate the influence on outcomes of factors related to the endoscopist. DESIGN: Multicenter retrospective study. SETTING: Public health system hospitals with experience in ESCP in Spain. PATIENTS: A total of 125 patients underwent ESCP in 19 hospitals, with an experience of <20 procedures. INTERVENTION: ESCP. MAIN OUTCOME MEASUREMENTS: Technical success and complication rates in the initial phase of implantation of ESCP are described. The influence of technical characteristics and endoscopist features on outcomes was analyzed. RESULTS: A total of 125 patients from 19 hospitals were included. Biliary ESCP was performed in 106 patients and pancreatic ESCP was performed in 19. Technical success was achieved in 84 patients (67.2%) followed by clinical success in 79 (63.2%). Complications occurred in 29 patients (23.2%). Unsuccessful manipulation of the guidewire was responsible for 68.2% of technical failures, and 58.6% of complications were related to problems with the transmural fistula. LIMITATIONS: Retrospective study. CONCLUSION: Outcomes of ESCP during its implantation stage reached a technical success rate of 67.2%, with a complication rate of 23.2%. Intraductal manipulation of the guidewire seems to be the most difficult stage of the procedure.

Control of crystallite orientation and size in Fe and FeCo nanoneedles.

Uniform magnetic nanoneedles have been prepared by hydrogen reduction of elongated nanoarchitectures. These precursors are as-prepared or cobalt-coated aggregates of highly oriented haematite nanocrystals (∼5 nm). The final materials are flattened nanoneedles formed by chains of assembled Fe or FeCo single-domain nanocrystals. The microstructural properties of such nanoneedles were tailored using renewed and improved synthetic strategies. In this fashion, the needle elongation and composition, the crystallite size (from 15 up to 30 nm), the nanocrystal orientation (with the 〈110〉 or 〈001〉 directions roughly along the long axis of the nanoneedle) and their type of arrangement (single chains, frustrated double chains and double chains) were controlled by modifying the reduction time, the axial ratio of the precursor haematite and the presence of additional coatings of aluminum or yttrium compounds. The values of the coercivity H(C) found for these nanoneedles are compared with the values predicted by the chain of spheres model assuming a symmetric fanning mechanism for magnetization reversal.

ERCP during pregnancy.

BACKGROUND AND AIMS: ERCP during pregnancy is always challenging for the entire team performing the endoscopic intervention. In this study techniques and different interventional aspects used at several centres about the clinical experience on ERCP in pregnant women are analyzed. PATIENTS AND METHODS: the practice on ERCP in pregnant women in six centres during a period of ten years is reported. RESULTS: eleven patients were included in the study. Mean age was 30.6 years. Indication for ERCP was always symptomatic common bile duct stone (CBDS) disease. Before the procedure abdominal ultrasound was performed at all times and magnetic resonance cholangiopancreatography in four occasions. Conscious sedation by means of midazolam and fentanyl or meperidine was applied. Sphincterotomes and guidewires were used for bilary cannulation. Sometimes, rapid exchange platforms with short-length guidewires controlled by the same endoscopist were employed. Biliary cannulation was confirmed in 9 occasions by bile aspiration. In five procedures, a mean of 30 seconds of fluoroscopy was used, both to verify cannulation and to corroborate complete CBDS clearance. These patients had the pelvic zone protected with a lead shield and radiation dose was measured. Ten biliary sphincterotomies were performed followed by CBDS extraction. Two plastic stents were inserted. Relief of biliary obstruction was attained in all circumstances. Only one patient had hyperamylasemia after ERCP. All pregnant women had healthy foetuses with normal deliveries. CONCLUSIONS: with experience, ERCP appears to be a safe technique during pregnancy. With simple measures fluoroscopic time can be diminished or even abolished. It seems that ERCP during pregnancy is underused in our working areas, although it has shown to be a useful technique for relieving biliary obstruction.