Intra-arterial infusion of nitric oxide (NO) - first animal trial

OBJECTIVE: Nitric oxide (NO) is an important signaling molecule that acts in many tissues to regulate a diverse range of physiological processes. NO has been implicated in a number of cardiovascular diseases. Reduced basal NO synthesis or function may lead to: vasoconstriction, elevated blood pressure and thrombus formation. By contrast, overproduction of NO results in vasodilatation, hypotension, vascular leakage, and disruption of cell metabolism. The purpose of this study was to determine the effects of NO gas directly infused into the arteries. METHODS: The study was performed on 28 rabbits and 10 pigs. We developed a device that enables quantitatively controlled infusion of NO gas, directly into the arteries. RESULTS: We found that administration of NO gas via arteries caused widening of the blood vessels as well as increasing blood flow in the extremity. It emerges that. These effects persist up to 2-3 h after the NO infusion ceased. Although the NO breaks down when diffused in blood, its influence commences rapidly and continues for a relatively long time. CONCLUSIONS: Our findings indicate that, administration of NO into blood vessels causes a long lasting vasodilatation and enhanced blood flow. Despite the fact that NO is broken down rapidly.     

Runtime application of Hybrid-Asbru clinical guidelines

Clinical guidelines are a major tool in improving the quality of medical care. However, to support the automation of guideline-based care, several requirements must be filled, such as specification of the guidelines in a machine-interpretable format and a connection to an Electronic Patient Record (EPR). For several different reasons, it is beneficial to convert free-text guidelines gradually, through several intermediate representations, to a machine-interpretable format. It is also realistic to consider the case when an EPR is unavailable. We propose an innovative approach to the runtime application of intermediate-represented Hybrid-Asbru guidelines, with or without an available EPR. The new approach capitalizes on our extensive work on developing the Digital electronic Guideline Library (DeGeL) framework. The new approach was implemented as the Spock system. For evaluation, three guidelines were specified in an intermediate format and were applied to a set of simulated patient records designed to cover prototypical cases. In all cases, the Spock system produced the expected output, and did not produce an unexpected one. Thus, we have demonstrated the capability of the Spock system to apply guidelines encoded in the Hybrid-Asbru intermediate representation, when an EPR is not available.     

Eliminating Cancer Stem Cells by Targeting Embryonic Signaling Pathways

Dramatic advances have been made in the understanding of cancer over the past decade. Prime among those are better appreciation of the biology of cancer and the development of targeted therapies. Despite these improvements, however, most tumors remain refractory to anti-cancer medications and frequently recur. Cancer Stem Cells (CSCs), which in some cases express markers of pluripotency (e.g., Oct-4), share many of the molecular features of normal stem cells. These cells have been hypothesised to play a role in tumor resistance and relapse. They exhibit dependence on many primitive regulatory pathways and may be best viewed in the context of embryonic signaling pathways. In this article, we review important embryonic signaling cascades and their differential expression in CSCs. We also discuss these pathways as actionable targets for novel therapies in hopes that eliminating cancer stem cells will lead to an improvement in overall survival for patients.     

Sex differences in the epidemiology, seasonal variation, and trends in the management of patients with acute appendicitis

Background

Acute appendicitis is the most common indication for acute surgical abdominal intervention. In this study, we analyzed the gender correlation with demographic, epidemiologic, diurnal, and seasonal trends in relation to the incidence and management of patients with acute appendicitis in our medical center.

Methods

Data of patients, 18?years of age or older who underwent emergency appendectomies at the Rabin Medical Center during the last 13?years, were collected. The data collected included demographic parameters, hospitalization, procedures, and use of preoperative imaging.

Results

Data were available for 3,736 patients. Males had more appendicitis attacks than females (p?<?0.0001), whereas females had more normal appendixes than males (p?<?0.0001). The overall rate of normal appendixes was 19.6?%, with a decline in the past 10?years from a yearly average of 23.5?% between 1998 and 2002 to 15?% between 2003 and 2007 (p?<?0.0001) with a reverse correlation with the preoperative use of abdominal CT. A distinct seasonal pattern was observed; more appendectomies for acute appendicitis occurred during the summer months (p?<?0.0001). Ten percent of patients had a complicated course with a mortality rate of 0.33?%; most of them were elderly, male/female ratio 0.4.

Conclusions

We found distinct gender, epidemiological, seasonal, and diurnal trends influencing the incidence of acute appendicitis. The incidence rate of false-positive surgery has been gradually declining, probably due to the increased use of preoperative abdominal CT and ultrasound. Acute appendicitis was more common in males and during the summer months.     

Follow-up of low-risk patients with differentiated thyroid carcinoma: a European perspective

OBJECTIVE: Because differentiated (follicular and papillary) thyroid cancer (DTC) may recur years after initial treatment, the follow-up of patients with DTC is long term. However, this population has changed, with more individuals being discovered at an earlier stage of the disease, so that previous follow-up protocols based mostly on data from high-risk patients no longer apply. We sought to develop an improved protocol for the follow-up of low-risk patients with DTC based on the findings of recent studies. METHODS: We analysed recent literature on the follow-up of DTC. RESULTS: Recent large studies have produced three important findings: (i) in patients with low-risk DTC with no evidence of disease up to the 6- to 12-month follow-up, diagnostic whole-body scan adds no information when serum thyroglobulin (Tg) is undetectable and interference from anti-Tg antibodies is absent; (ii) use of recombinant human thyroid-stimulating hormone to aid Tg measurement is effective and provides greater safety, quality-of-life and work productivity than does levothyroxine withdrawal with its attendant hypothyroidism; and (iii) ultrasonography performed by an experienced operator is the most sensitive means of detecting neck recurrences of DTC. CONCLUSIONS: We present a revised follow-up protocol for low-risk patients taking into account the above findings. This protocol should help clinicians enter a new era of monitoring characterized by greater safety, simplicity, convenience and cost savings.     

Harnessing RNAi-based nanomedicines for therapeutic gene silencing in B-cell malignancies

Despite progress in systemic small interfering RNA (siRNA) delivery to the liver and to solid tumors, systemic siRNA delivery to leukocytes remains challenging. The ability to silence gene expression in leukocytes has great potential for identifying drug targets and for RNAi-based therapy for leukocyte diseases. However, both normal and malignant leukocytes are among the most difficult targets for siRNA delivery as they are resistant to conventional transfection reagents and are dispersed in the body. We used mantle cell lymphoma (MCL) as a prototypic blood cancer for validating a novel siRNA delivery strategy. MCL is an aggressive B-cell lymphoma that overexpresses cyclin D1 with relatively poor prognosis. Down-regulation of cyclin D1 using RNA interference (RNAi) is a potential therapeutic approach to this malignancy. Here, we designed lipid-based nanoparticles (LNPs) coated with anti-CD38 monoclonal antibodies that are specifically taken up by human MCL cells in the bone marrow of xenografted mice. When loaded with siRNAs against cyclin D1, CD38-targeted LNPs induced gene silencing in MCL cells and prolonged survival of tumor-bearing mice with no observed adverse effects. These results highlight the therapeutic potential of cyclin D1 therapy in MCL and present a novel RNAi delivery system that opens new therapeutic opportunities for treating MCL and other B-cell malignancies.RNA interference (RNAi) can be activated by introducing synthetic short double-stranded RNA fragments, termed small interfering RNAs (siRNAs), into cells to silence genes bearing complementary sequences. RNAi holds great promise as a powerful tool for evaluating the role of specific genes in cellular and disease processes and for therapeutic applications (1, 2). siRNAs that manipulate gene expression in leukocytes could be used to understand hematologic cell biology and to develop novel therapeutic approaches to dampen inflammation and the harmful immune responses that occur during autoimmunity; to suppress lymphotropic viral infections, such as HIV; or to treat blood cancers (3). However, the lack of systemic delivery startegies to target leukocytes foils these applications.Here we devised a new strategy to target B-cell malignancies using mantle cell lymphoma (MCL) as a prototypic blood cancer to validate this siRNA delivery approach. MCL is an aggressive B-cell malignancy characterized by a t(11:14) chromosomal translocation that juxtaposes the proto-oncogene encoding cyclin D1 (cycD1) to the Ig heavy chain gene promotor (4). This leads to constitutive overexpression of cycD1, a protein that is not expressed in healthy B-lymphocytes. Current MCL therapy relies mainly on conventional chemotherapy; anti-CD20 cytotoxic monoclonal antibodies; autologous stem cell transplantation; and, more recently, small molecule inhibitors of critical molecular pathways, such as the BTK inhibitor ibrutinib (5). Unfortunately, relapse and progressive resistance to treatment lead to short median survival. MCL has one of the worst prognoses among lymphomas (6–8). Thus, there is a need for new therapeutic approaches.We previously showed that cycD1 down-regulation in MCL cell lines using RNAi inhibits proliferation and causes cell cycle arrest and apoptosis (9). However, the clinical application of this approach is hindered by the lack of appropriate systems that could deliver RNAi payloads to MCL cells in an efficient and safe manner (10, 11). RNAi therapeutics for B-cell malignancies is especially challenging because these cells are dispersed and are intrinsically resistant to transfection with nucleic acids (3, 12, 13). Therefore, to test the potential therapeutic effect of cycD1 inhibition in vivo and to demonstrate the feasibility of RNAi therapeutics in MCL, we needed to develop a suitable RNAi-delivery platform for potent gene silencing.Lipid-based nanoparticles (LNPs), composed of ionizable lipids that incorporate siRNAs, can induce potent gene silencing in the liver (14, 15). These are currently being evaluated in a phase III clinical study to knock down the TTR gene expressed in the liver to treat familial amyloidosis (16). We recently demonstrated that LNPs could be surface-modified with a natural ligand or a monoclonal antibody to improve in vivo delivery of siRNA payloads (17, 18). Here we investigate the use of antibody-targeted LNPs to deliver siRNAs to MCL cells. The blood supply in the hematological tissues where MCL cells mostly reside, including spleen and bone marrow, is made up of sinusoids that allow small nanoparticles tissue access. Selective targeting of lymphoma cells by antibody-targeted delivery should be clinically beneficial because it could reduce the total amount of drug required for therapeutic benefit and reduce toxicity to bystander cells (2, 12).CD38 is expressed on the surface of immature hematopoietic cells, including immature B cells. Its expression is tightly regulated during B-cell ontogeny; it is expressed on bone marrow precursors, but not mature B cells. CD38 is expressed on most MCLs (19). In the present study, we show that CD38 is a suitable target for antibody-mediated delivery of therapeutic siRNAs to MCL. LNPs–siRNA coated with an anti-CD38 monoclonal antibody (αCD38 mAb) showed specific MCL binding in vitro (in MCL cell lines and MCL primary lymphomas) and in vivo (in mice xenografted with a human MCL cell line). CD38-targeted LNPs (αCD38-LNPs) entrapping siRNA against cycD1 (siCycD1) were specifically taken up by MCL xenografts. αCD38-LNPs-siCycD1 induced gene silencing, suppressed tumor cell growth in vitro, and prolonged the survival of MCL-bearing mice. Our data demonstrate the effectiveness of inhibiting cycD1 in MCL in vivo and highlight αCD38–LNPs–siRNA as part of a strategy that could ultimately become a novel therapeutic modality for treating MCL and other CD38-expressing hematological malignancies.     

Antiinflammatory effects of the phosphodiesterase-4 inhibitor cilomilast (Ariflo) in chronic obstructive pulmonary disease

Cilomilast (Ariflo), a new oral phosphodiesterase-4 selective inhibitor, improves lung function in chronic obstructive pulmonary disease (COPD). We have evaluated its antiinflammatory effects in 59 patients with COPD randomized to receive cilomilast, 15 mg two times a day, or placebo for 12 weeks. Induced sputum differential cell counts were obtained at baseline and at five further visits. Interleukin-8 and neutrophil elastase were measured in sputum supernatant. Bronchial biopsies obtained at baseline and at Week 10 were immunostained and counted for neutrophils, CD8+ and CD4+ T-lymphocyte subsets, and CD68+ macrophages. Cells expressing the genes for interleukin-8 and tumor necrosis factor-alpha were identified by in situ hybridization and quantified. Compared with placebo, analysis of variance (ANOVA) of the change from baseline showed that cilomilast did not alter any sputum endpoint or FEV1. However, bronchial biopsies demonstrated that cilomilast treatment was associated with reductions in CD8+ (p = 0.001; ANOVA) and CD68+ cells (p < 0.05; ANOVA). In addition, by Poisson analysis, comparison of cell counts analyzed as a ratio of active to placebo demonstrated reductions of CD8+ (48% p < 0.01) and CD68+ (47% p = 0.001) cells. This is the first demonstration of reduction by any agent of airway tissue inflammatory cells characteristic of COPD. Phosphodiesterase-4 inhibitors represent a promising new class of substances for use in antiinflammatory treatment of this disease.     

Neuropsychological deficits in choreoacanthocytosis

Little is known about the cognitive deficits associated with choreoacanthocytosis. This case report focuses on the neuropsychological deficits of a woman diagnosed with choreoacanthocytosis. The similarity between her cognitive deficits and those of patients with Huntington's disease is consistent with the neuropathology of the two disorders. The findings of this study suggest that careful neuropsychological assessment of patients with choreoacanthocytosis is warranted, since cognitive impairment may well be a clinical feature of the disorder.