Title: Leadless Pacemakers in Post Operative Patients: Is It Time For the New to Become the Normal?Invited Editorial: Manuscript ID JCE-23-0567.R2Tyler P. Rasmussen, MD, PhD and E. Michael Powers, MD, MBAUniversity of Iowa Carver College of MedicineDivision of Cariology, Clinical Cardiac Electrophysiology200 Hawkins Dr.Iowa City, IA 52242Edwardemail@example.comMerchant et al. describe a single center retrospective analysis of leadless pacemaker (LP) implant following cardiac surgery or transcatheter valvular procedures that highlights the performance of LPs when implanted in patients with atrioventricular block (AVB) and either high risk features for conventional transvenous pacing or permanent atrial fibrillation (1). LPs performed well with a limited number of patients (7%) requiring conversion to transvenous pacing and only a single procedural complication. However, there was a statistically significant decline in left ventricular ejection fraction (LVEF) in the overall cohort. When subgroup analysis was performed, LVEF decline was only seen in those implanted with VVI devices but not in patients with VDD devices. Here, we discuss implications of this study.Transcatheter aortic valve implantation (TAVI) is now more common than surgical AVR but carries a greater risk of high degree atrioventricular block (AVB) (~10%) (2,3). Cardiac surgery has been linked to a 1-3% risk of permanent pacemaker implantation with higher rates in patients undergoing valve replacement (4). Therefore, the number of patients at risk for AVB related to cardiac surgery and catheter-based valve interventions is increasing over time and warrants a critical evaluation of optimal pacing strategy.Longitudinal registry data show that Micra (Medtronic, Minneapolis, MN) LPs have fewer required reinterventions and chronic complications compared to conventional transvenous pacing systems (5). Furthermore, mortality is comparable despite being implanted in patients with higher rates of end stage renal disease (ESRD) and medical complexity (5). LPs greatly outperform transvenous systems with respect to device related infections, as the rate of infection in LPs is trivial both short and long term (5,6). The risk of pacing induced cardiomyopathy (LVEF drop ≥ 10%) in pacemaker dependent patients is suggested to be equivalent or lower in those implanted with an LP (3%) versus those with a transvenous system (~13%) (7). A major drawback to the use of LPs is their inability to provide atrial pacing, which typically limits their use to patients without sinus node dysfunction.The current paper demonstrates that the use of LPs is a viable strategy in post-operative patients. Their cohort included 50 patients having undergone cardiac surgery and 28 with a transcatheter valvular procedure (1). Of the 28 transcatheter procedures, 25 were TAVI. Factors prompting an LP implant versus transvenous were permanent AF, ESRD, tricuspid valve pathology, history of endovascular infection, and dermatological disease. Mean time from surgery to device implant was 7.3 ± 8.0 days, which suggests an adequate waiting period for AV conduction recovery in most circumstances. The only complication in the cohort (1.3%) was an access site hematoma requiring evacuation. Device parameters were stable at follow-up with a small but clinically insignificant decline in impedance and trivial rise in threshold, which is consistent with previously published data regarding Micra (6). The two major findings were that the pacing burden declined significantly in the follow-up period and that there was a significant reduction in the left ventricular ejection fraction (LVEF) in this cohort. Pacing percentages fell from mean 75% at implant to mean 48% at follow-up. The reduction in pacing burden suggests that many patients have late recovery in AV conduction post procedure. There was a drop in LVEF from baseline (55.0% ± 10.6%) versus follow-up (51.5% ± 11.2%, p =< 0.001), but this study is not designed to determine if the LVEF drop is because of the Micra or another unidentifiable factor. Importantly, the drop in LVEF was significant in the Micra VR group: baseline (54.1% ± 11.9%) versus follow-up (48.8% ± 11.9%, p = 0.003) but not in the Micra AV group: baseline (56.1 ± 9.0%) versus (54.6% ± 9.7%, p = 0.06). The only patient characteristic that was associated with a significant drop in LVEF (> 10%) versus those with stable EF was having a prior history of heart failure with a reduced ejection fraction. Taken together, this study showed that both Micra AV and VR can provide safe RV pacing in post-operative patients with a small, but significant risk for LVEF reduction that is likely linked to right ventricular pacing.
Emeritus Professor Margaret Baird forged a luminary career for her pioneering research investigating the role of dendritic cells (DCs) in cancer and infectious diseases, as an inspirational lecturer at the University of Otago and a role model to many. In this article celebrating the 100-year anniversary of ICB, we discuss Margaret’s career and life journey through the eyes of her family and co-authors, as we explore her many publications in ICB and beyond.
Caseous mitral annulus calcification mimicking a cardiac tumor Henda Nèji a,b,c, Emna Bennour b,d, , Ines Baccouche a,c, Salma Kechaou a,c, Ikram Kammoun b,d, Meriem Affes a,b,cSaoussen Hantous-Zannad a,b,ca: Imaging Department, Abderrahmen Mami Hospital, Ariana – Tunisiab: Faculty of Medicine of Tunis, University Tunis El Manar, Tunisiac: Cardio-thoracic imaging Research Laboratoryd: Cardiology Department
Catchment modelling has undergone tremendous developments during the past decades. In the 1970s, the focus was on simulation of catchment runoff with process descriptions and data inputs being lumped to the catchment scale. Later developments included spatially distributed models allowing data inputs and hydrological processes to be simulated at model grid scale, i.e. much finer than catchment scale. These models were able to explicitly simulate various processes such as soil moisture, evapotranspiration, groundwater and surface runoff. With the advancements in remote sensing technology and availability of high-resolution data, increased attention has in recent years been given to enhancing the capability of catchment models to reproduce spatial patterns and in this way improve our understanding of hydrological processes and the physical realism of catchment models. This development process has involved a wide spectrum of different aspects in the modelling process, reaching from an improved understanding of uncertainties in data, model parameters and model structures to new protocols for good modelling practices in water management. Recognizing the important role of biodiversity and social aspects, hydrologists are now extending the scope of their models to capture the interactions between water, biota and human social systems.
A Pediatric Case of Neuromyelitis Optica and Pulmonary Inflammatory Myofibroblastic TumorAlyson Win, BS (firstname.lastname@example.org)a : Conceptualization; writing- original draft; writing- review and editing.Jesper Jiang, BS (email@example.com)a:Conceptualization; writing- original draft. John Fitzwater, MD (john.fitzwater@BSWHealth.org)b : writing- review and editing; supervision. Edwin Hernandez Caro, MD (Edwin.Caro@BSWHealth.org)c : writing- review and editing. Amy Cruickshank, DO (Amy.Cruickshank@BSWHealth.org)d : writing- review and editing. Duriel Hardy, MD (Duriel.Hardy@austin.utexas.edu)e : writing- review and editing. Ydamis Estrella Perez, MD (Ydamis.Perez@BSWHealth.org)f : writing- review and editing. Michele Prater, PNP (JMichele.Prater@BSWHealth.org)c: writing- review and editing. Malvika Sagar, MD (Malvika.Sagar@BSWHealth.org)c : Conceptualization; writing- review and editing; supervision.a: Texas A&M Health Science Center School of Medicine, Temple, TXb: Department of Pediatric Surgery, Baylor Scott and White McClane Children’s Medical Center, Temple, TXc: Department of Pediatric Pulmonology, Baylor Scott and White McClane Children’s Medical Center, Temple, TXd: Department of Pediatric Hematology/Oncology, Baylor Scott and White McClane Children’s Medical Center, Temple, TXe: Department of Pediatric Neurology, Dell Children’s Medical Center, Austin, TXf: Department of Pathology, Baylor Scott and White Medical Center, Temple, TX
A historic challenge for shotgun proteomics has been the requirement for high quality, simple and nonredundant curated protein sequences in small .fasta text files. Due to the intrinsic informatic challenges and time required to assemble these files, proteomics has struggled to expand beyond the confines of a few model organisms. When considering post-translational modifications that may or may not be present on a specific peptide sequence, these factors inevitably compound. A study on how mangos continue to ripen on the shelf may not be the first thing you'd think of as proof of a scientific discipline shedding historic limitations. However, Bautiste-Valle et al., may be just that. These authors present a quantitative comparison of both peptide and glycopeptide alterations through the complexity of the fruit ripening process and in this we see the present state of a field that no longer needs to wait on genomics to obtain deep mechanistic insights.
Colitis cystica profunda (CCP) is a rare benign disease characterized by mucus-filled cysts in the submucosa, sometimes similar to malignant tumors. Endoscopic, radiological and even histological examinations are not highly specific, which can easily lead to missed diagnosis and misdiagnosis, resulting in unnecessary radical surgical resection. In this report, we present
Prior studies found hand preference trajectories predict preschool language outcomes. However, this approach has been limited to examining bimanual manipulation in toddlers. It is not known whether hand preference during infancy for acquiring objects (i.e., reach-to-grasp) similarly predicts childhood language ability. The current study explored this motor-language developmental cascade in 90 children. Hand preference for acquiring objects was assessed monthly from 6 to 14 months and language skill was assessed at 5 years. Latent class growth analysis identified three infant hand preference classes: left, early right, and late right. Infant hand preference classes predicted 5-year language skills. Children in the left and early right classes, who were categorized as having a consistent hand preference, had higher expressive and receptive language scores relative to children in the inconsistent late right class. Consistent classes did not differ from each other on language outcomes. Infant hand preference patterns explained more variance for expressive and receptive language relative to previously reported toddler hand preference patterns, above and beyond socioeconomic status (SES). Results suggest that hand preference, measured at different time points across development using a trajectory approach, is reliably linked to later language.
RATIONALE: The thiosuccinimide linker is widely used in the synthesis of bioconjugates. However, it is susceptible to hydrolysis and is transformed into its hydrolyzed and/or the isobaric thiazine forms, the latter of which is a fairly common product in a conjugate that contains a cysteinyl peptide. MALDI-MS and MS/MS are useful for differentiating these isobaric species. METHODS: Four cross-linked peptides with thiosuccinimide linkers were synthesized. Analogs with the linker that were transformed into thiazine and/or the hydrolyzed thiosuccinimide linkers were then generated by incubating the samples at neutral or basic pH. All of the cross-linked peptides were purified by rp-HPLC and differentiated by MALDI-MS, -MS/MS and UVPD. RESULTS: A cysteinyl peptide-containing conjugate, the thiosuccinimide form, was largely transformed into the hydrolyzed or thiazine forms after incubation at neutral or basic pH. MALDI-MS allowed the three forms to be differentiated: the thiosuccinimide and its hydrolysis product gave two constituent peptides after reductive cleavage between the Cys and succinimide moieties; no fragment ions were produced from the thiazine form. In addition, MALDI-MS/MS of the thiosuccinimide form yielded two pairs of complementary fragment ions via 1,4-elimination: Cys-SH and maleimide, and dehydro-alanine and thiosuccinimide, which are different from those produced via reductive cleavage in MALDI-MS. The thiazine form gave fragment ions resulting from the cleavage of the newly formed amide bond in the linker that arose from thiazine formation. CONCLUSIONS: The thiosuccinimide (but not thiazine) form of the cross-linked peptide yielded individual constituent peptides in MALDI-MS; MALDI-MS/MS showing specific 1,4-elimination for the thiosuccinimide form and cleavage at the newly formed peptide bond via transcyclisation for the thiazine form.
IntroductionA volvulus occurs when a segment of intestine, usually part of the colon, twists around its mesentery. Following this rotation, initially venous return is disturbed and causes ischemia caused by venous stasis. With the prolongation of obstruction in the mesenteric vessels, along with the distention of the twisted segment of the intestine due to the progressive production of gas by the bacteria inside it, the arterial input is also disturbed, and the mucosal ischemia gradually progresses towards the muscular and serous layers, leading to perforation of the entire thickness of the intestineSigmoid volvulus accounts for 2% to 5% of colonic obstructions in Western countries and 20% to 50% of colonic obstructions in Eastern countries (1). This occurs mostly in patients with lack of mobility and a history of chronic constipation, where the sigmoid colon becomes chronically distended and redundant.Undescended testis (UDT) is defined as one or both testicles absent in scrotal sac when descending processes become disturbed and testis remains inside the peritoneal cavity (2). There are some very known complications of a undescendent intra-abdominal testicle such as cancer, ischemia and infertility(3); But the rotation of the colon around the spermatic cord of one UDT, it is a very rare phenomenon that there is no similar report.In this article, we introduce a 67-year-old man who underwent laparotomy with the diagnosis of sigmoid volvulus, and the intraoperative findings were surprising.
Transition metal-catalyzed asymmetric transfer hydrogenation has been proved to be a powerful approach for the synthesis of chiral alcohols. Herein, A highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(III) catalyst has been successfully developed, and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) with high yields and enantioselectivities. With this method, the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized, providing the key intermediate of baloxavir marboxil with >99% yield and >99% ee at a substrate/catalyst molar ratio of 1000.
Furans bearing alkynyl substituents are highly useful in organic synthesis. However, the methodologies to access these important furan derivatives are rather limited. We herein report an efficient synthesis of alkynylated furan derivatives based on Pd-catalyzed oxidative cross-coupling reaction between allenyl ketones and terminal alkynes. This novel synthesis of alkynylated furans with wide substrate scope is operationally simple and tolerates various functional groups. Mechanistically, the formation of the palladium carbene through cycloisomerization and the subsequent alkynyl migratory insertion are proposed as the key steps in the transformation. The reaction reported in this manuscript further demonstrates the generality of the carbene-based cross coupling.
INTRODUCTIONTakotsubo syndrome is an acute heart disease that mimics the typical features of acute coronary syndrome (ACS) . Although takotsubo syndrome has an uncertain prevalence in the general population, in women with suspected ACS, the prevalence is estimated to be around 5-6% . The annual incidence is very low and is approximately 0.02% .Unlike ACS, TS is reversible and the heart often heals within four to eight changes weeks. The syndrome is characterised by transient systolic and diastolic left ventricular dysfunction with wall motion abnormalities . This condition, which was first described by Dote et al. in Japan in 1990 , usually affects postmenopausal women who have experienced some physical or psychological stress. However, it can also occur in the absence of these triggers .The prevalence of saccular aneurysms in the general population is estimated at 3.2%. Approximately 20 to 30% of cases present in the form of multiple aneurysms . Intracranial aneurysms are generally diagnosed after episodes of subarachnoid haemorrhage (SAH), which causes a high rate of morbidity and mortality . Rupture of an aneurysm is believed to be responsible for 0.4 to 0.6% of all aneurysm deaths, and approximately 10% of patients die before arriving at the hospital. Takotsubo syndrome is generally reported to have an incidence of 0.8-17% in patients with SAH caused by ruptured aneurysm . However, this case report is relevant for the clinical and pathophysiological observation of the possible association between aneurysms of the internal carotid arteries (ICA) and TS, with the latter being able to serve as an alert for possible aneurysms and thus allow for intervention prior to disruption.
Here, we report a cobalt-catalyzed sequential dehydrogenative Heck silylation/hydroamination of styrenes with hydrosilane and diazo compound to access 1-amino-2-silyl compounds with excellent regioselectivity. This difunctionalization reaction could undergo smoothly using 1 mol% catalyst loading with good functional group tolerance. Not only di- and tri-substituted hydrosilanes, but also alkoxysilane are suitable, which does explore the scope of the family of 1-amino-2-silyl compounds. The ligand relay phenomenon between neutral tridentate NNN ligand and anionic NNN ligand is observed for the first time via absorption spectra analysis in this one-pot, two-step transformations. The primary mechanism has been proposed based on the control experiments.