Novel approaches in development of cell penetrating peptides

Therapeutic cargos which are impermeable to the cell can be delivered by cell penetrating peptides (CPPs). CPP-cargo complexes accumulate by endocytosis inside the cells but they fail to reach the cytosolic space properly as they are often trapped in the endocytic organelles. Here the CPP mediated endosomal escape and some strategies used to increase endosomal escape of CPP-cargo conjugates are discussed with evidence. Potential benefits can be obtained by peptides such as reduction in side effects, biocompatibility, easier synthesis and can be obtained at lower administered doses. The particular peptide known as cell penetrating peptides are able to translocate themselves across membrane with the carrier drugs with different mechanisms.  This is of prime importance in drug delivery systems as they have capability to cross physiological membranes. This review describes various mechanisms for effective drug delivery and associated challenge

Echocardiography allows for analysis of pulmonary arterial flow in mice with congenital diaphragmatic hernia

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a structural birth defect associated with pulmonary hypoplasia and pulmonary arterial hypertension (PAH). We hypothesize that echocardiography provides a method to assess real-time right ventricle (RV) function, remodeling, and pulmonary artery (PA) flow. MATERIALS AND METHODS: Slit3 wild-type (WT) (n = 6) and knockout (KO) (n = 5) mice were analyzed at 2-3 months of age. Mice were anesthetized using isoflurane. Echocardiography was performed to analyze left and right ventricular wall thickness, internal diameter (ID), and function. Color Doppler was used to analyze flow in the PA and across the tricuspid valve. RESULTS: There was significant RV dilation in the KO mice versus WT, with an average RVID of 1.99 mm versus 1.26 mm, respectively (P = 0.007). Flow in the PA of KO mice was altered compared to WT, with elevated PA velocity time indices, 30.68 mm versus 22.13 mm (P = 0.012), elevated PA peak velocities, 952.61 mm/s versus 628.73 mm/s (P = 0.003), and decreased pulmonary acceleration times, 8.94 ms versus 16.18 ms (P = 0.002), respectively. Pulmonary vascular resistance, calculated by measuring tricuspid regurgitation peak velocity and right ventricular outflow tract velocity time index, was increased in KO versus WT mice, 17.61 mm2/s versus 8.91 mm2/s (P = 0.003), respectively. CONCLUSIONS: Slit3 KO mice with CDH show evidence of PAH and resultant RV dilation. Using direct cardiac puncture, elevated RV systolic pressures have been demonstrated in KO mice as evidence of PAH. Echocardiography allows direct analysis of the PA and real-time RV function without sacrifice of the mouse. This mode of evaluation allows longitudinal study in mice with PAH and CDH

Pros and Cons of Marijuana in Treatment of Parkinson's Disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder of adult onset in the United States. It is a debilitating condition and presents with both motor and non-motor symptoms. Current treatment options are scarce and include replacement of dopamine deficiency with levodopa which targets only motor symptoms of the disorder, does not halt its progression, and is associated with side effects of its own, including dyskinesia. With medical marijuana gaining popularity and being legalized in the United States, we examined the pros and cons of marijuana in the treatment of Parkinson's disease

Effect of Perflubron-induced lung growth on pulmonary vascular remodeling in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) involves lung hypoplasia and pulmonary hypertension (PH). Post-natal Perflubron ventilation induces lung growth. This phenomenon is called Perflubon-induced lung growth (PILG). However, it does not appear to ameliorate PH in CDH. We aim to determine the effect of PILG on pulmonary vascular remodeling in neonates with CDH and PH requiring extracorporeal membrane oxygenation (ECMO)

A method for evaluating the murine pulmonary vasculature using micro-computed tomography

AbstractBackgroundSignificant mortality and morbidity are associated with alterations in the pulmonary vasculature. While techniques have been described for quantitative morphometry of whole-lung arterial trees in larger animals, no methods have been described in mice. We report a method for the quantitative assessment of murine pulmonary arterial vasculature using high-resolution computed tomography scanning.MethodsMice were harvested at 2 weeks, 4 weeks, and 3 months of age. The pulmonary artery vascular tree was pressure perfused to maximal dilation with a radio-opaque casting material with viscosity and pressure set to prevent capillary transit and venous filling. The lungs were fixed and scanned on a specimen computed tomography scanner at 8-μm resolution, and the vessels were segmented. Vessels were grouped into categories based on lumen diameter and branch generation.ResultsRobust high-resolution segmentation was achieved, permitting detailed quantitation of pulmonary vascular morphometrics. As expected, postnatal lung development was associated with progressive increase in small-vessel number and arterial branching complexity.ConclusionsThese methods for quantitative analysis of the pulmonary vasculature in postnatal and adult mice provide a useful tool for the evaluation of mouse models of disease that affect the pulmonary vasculature

Timing of early excision and grafting following burn in sub-Saharan Africa

This study sought to establish appropriate timing of burn wound excision and grafting in a resource-poor setting in sub-Saharan Africa

Epigenetic reprogramming of breast cancer cells with oocyte extracts

<p>Abstract</p> <p>Background</p> <p>Breast cancer is a disease characterised by both genetic and epigenetic alterations. Epigenetic silencing of tumour suppressor genes is an early event in breast carcinogenesis and reversion of gene silencing by epigenetic reprogramming can provide clues to the mechanisms responsible for tumour initiation and progression. In this study we apply the reprogramming capacity of oocytes to cancer cells in order to study breast oncogenesis.</p> <p>Results</p> <p>We show that breast cancer cells can be directly reprogrammed by amphibian oocyte extracts. The reprogramming effect, after six hours of treatment, in the absence of DNA replication, includes DNA demethylation and removal of repressive histone marks at the promoters of tumour suppressor genes; also, expression of the silenced genes is re-activated in response to treatment. This activity is specific to oocytes as it is not elicited by extracts from ovulated eggs, and is present at very limited levels in extracts from mouse embryonic stem cells. Epigenetic reprogramming in oocyte extracts results in reduction of cancer cell growth under anchorage independent conditions and a reduction in tumour growth in mouse xenografts.</p> <p>Conclusions</p> <p>This study presents a new method to investigate tumour reversion by epigenetic reprogramming. After testing extracts from different sources, we found that axolotl oocyte extracts possess superior reprogramming ability, which reverses epigenetic silencing of tumour suppressor genes and tumorigenicity of breast cancer cells in a mouse xenograft model. Therefore this system can be extremely valuable for dissecting the mechanisms involved in tumour suppressor gene silencing and identifying molecular activities capable of arresting tumour growth. These applications can ultimately shed light on the contribution of epigenetic alterations in breast cancer and advance the development of epigenetic therapies.</p

CXCR2 and CXCL4 regulate survival and self-renewal of hematopoietic stem/progenitor cells

The regulation of hematopoietic stem cell (HSC) survival and self-renewal within the bone marrow (BM) niche is not well understood. We therefore investigated global transcriptomic profiling of normal human hematopoietic stem/progenitor cells, revealing that several chemokine ligands (CXCL1-4, CXCL6, CXCL10, CXCL11, CXCL13) were up-regulated in human quiescent CD34+Hoescht-Pyronin Y- and primitive CD34+38-, as compared to proliferating CD34+Hoechst+Pyronin Y+ and CD34+38+ stem/progenitor cells. This suggested that chemokines may play an important role in the homeostasis of HSCs. In human CD34+ hematopoietic cells, knock-down of CXCL4 or pharmacological inhibition of the chemokine receptor CXCR2, significantly decreased cell viability and colony forming cell (CFC) potential. Studies on Cxcr2-/- mice demonstrated enhanced BM and spleen cellularity, with significantly increased numbers of HSC, hematopoietic progenitor cell (HPC)-1, HPC-2 and Lin-Sca-1+c-Kit+ sub-populations. Cxcr2-/- stem/progenitor cells showed reduced self-renewal capacity as measured in serial transplantation assays. Parallel studies on Cxcl4 demonstrated reduced numbers of CFC in primary and secondary assays following knock-down in murine c-Kit+ cells and Cxcl4-/- mice showed a decrease in HSC and reduced self-renewal capacity after secondary transplantation. These data demonstrate that the CXCR2 network and CXCL4 play a role in the maintenance of normal hematopoietic stem/progenitor cell fates, including survival and self-renewal

Hsa-mir183/EGR1-mediated regulation of E2F1 is required for CML stem/progenitor cell survival

Chronic myeloid leukemia (CML) stem/progenitor cells (SPC) express a transcriptional program characteristic of proliferation, yet can achieve and maintain quiescence. Understanding the mechanisms by which leukemic SPC maintain quiescence will help to clarify how they persist during long-term targeted treatment. We have identified a novel BCR-ABL1 protein kinase dependent pathway mediated by the up-regulation of hsa-mir183, the down-regulation of its direct target EGR1 and, as a consequence, up-regulation of E2F1. We show here that inhibition of hsa-mir183 reduced proliferation and impaired colony formation of CML SPC. Downstream of this, inhibition of E2F1 also reduced proliferation of CML SPC, leading to p53-mediated apoptosis. In addition, we demonstrate that E2F1 plays a pivotal role in regulating CML SPC proliferation status. Thus, for the first time, we highlight the mechanism of hsa-mir183/EGR1-mediated E2F1 regulation and demonstrate this axis as a novel, critical factor for CML SPC survival, offering new insights into leukemic stem cell eradication

Direct access cancer testing in primary care: a systematic review of use and clinical outcomes.

BACKGROUND: Direct access (DA) testing allows GPs to refer patients for investigation without consulting a specialist. The aim is to reduce waiting time for investigations and unnecessary appointments, enabling treatment to begin without delay. AIM: To establish the proportion of patients diagnosed with cancer and other diseases through DA testing, time to diagnosis, and suitability of DA investigations. DESIGN AND SETTING: Systematic review assessing the effectiveness of GP DA testing in adults. METHOD: MEDLINE, Embase, and the Cochrane Library were searched. Where possible, study data were pooled and analysed quantitatively. Where this was not possible, the data are presented narratively. RESULTS: The authors identified 60 papers that met pre-specified inclusion criteria. Most studies were carried out in the UK and were judged to be of poor quality. The authors found no significant difference in the pooled cancer conversion rate between GP DA referrals and patients who first consulted a specialist for any test, except gastroscopy. There were also no significant differences in the proportions of patients receiving any non-cancer diagnosis. Referrals for testing were deemed appropriate in 66.4% of those coming from GPs, and in 80.9% of those from consultants; this difference was not significant. The time from referral to testing was significantly shorter for patients referred for DA tests. Patient and GP satisfaction with DA testing was consistently high. CONCLUSION: GP DA testing performs as well as, and on some measures better than, consultant triaged testing on measures of disease detection, appropriateness of referrals, interval from referral to testing, and patient and GP satisfaction