Nasal delivery of donepezil HCl-loaded hydrogels for the treatment of Alzheimer's disease.

This study aims to prepare, characterize and evaluate the pharmacokinetics of liposomal donepezil HCl (LDH) dispersed into thiolated chitosan hydrogel (TCH) in rabbits. Various hydrogels including TCH were prepared, and after characterization, TCH was selected for subsequent evaluations, due to the promising results. TCH was then incorporated with LDH prepared by reverse phase evaporation method. The hydrogel was characterized using scanning electron microscope, dialysis membrane technique, and ultra-performance liquid chromatography methods. The optimized resultant was then evaluated in terms of pharmacokinetics in an in vivo environment. The mean size of LDH and drug entrapment efficiency were 438.7 ± 28.3 nm and 62.5% ± 0.6, respectively. The controlled drug release pattern results showed that the half-life of the loaded drug was approximately 3.5 h. Liposomal hydrogel and free liposomes were more stable at 4 °C compared to those in 20 °C. The pharmacokinetics study in the rabbit showed that the optimized hydrogel increased the mean peak drug concentration and area under the curve by 46% and 39%, respectively, through nasal route compared to the oral tablets of DH. Moreover, intranasal delivery of DH through liposomal hydrogel increased the mean brain content of the drug by 107% compared to the oral DH tablets. The results suggested that liposomes dispersed into TCH is a promising device for the nasal delivery of DH and can be considered for the treatment of Alzheimer's disease.

Correction: Activation of Notch Signaling Is Required for Cholangiocarcinoma Progression and Is Enhanced by Inactivation of p53 In Vivo.

[This corrects the article DOI: 10.1371/journal.pone.0077433.].

Prioritizing problems in and solutions to homecare safety of people with dementia: supporting carers, streamlining care.

BACKGROUND: Dementia care is predominantly provided by carers in home settings. We aimed to identify the priorities for homecare safety of people with dementia according to dementia health and social care professionals using a novel priority-setting method. METHODS: The project steering group determined the scope, the context and the criteria for prioritization. We then invited 185 North-West London clinicians via an open-ended questionnaire to identify three main problems and solutions relating to homecare safety of people with dementia. 76 clinicians submitted their suggestions which were thematically synthesized into a composite list of 27 distinct problems and 30 solutions. A group of 49 clinicians arbitrarily selected from the initial cohort ranked the composite list of suggestions using predetermined criteria. RESULTS: Inadequate education of carers of people with dementia (both family and professional) is seen as a key problem that needs addressing in addition to challenges of self-neglect, social isolation, medication nonadherence. Seven out of top 10 problems related to patients and/or carers signalling clearly where help and support are needed. The top ranked solutions focused on involvement and education of family carers, their supervision and continuing support. Several suggestions highlighted a need for improvement of recruitment, oversight and working conditions of professional carers and for different home safety-proofing strategies. CONCLUSIONS: Clinicians identified a range of suggestions for improving homecare safety of people with dementia. Better equipping carers was seen as fundamental for ensuring homecare safety. Many of the identified suggestions are highly challenging and not easily changeable, yet there are also many that are feasible, affordable and could contribute to substantial improvements to dementia homecare safety.

Preventing delayed diagnosis of cancer: clinicians' views on main problems and solutions.

BACKGROUND: Delayed diagnosis is a major contributing factor to the UK's lower cancer survival compared to many European countries. In the UK, there is a significant national variation in early cancer diagnosis. Healthcare providers can offer an insight into local priorities for timely cancer diagnosis. In this study, we aimed to identify the main problems and solutions relating to delay cancer diagnosis according to cancer care clinicians. METHODS: We developed and implemented a new priority-setting approach called PRIORITIZE and invited North West London cancer care clinicians to identify and prioritize main causes for and solutions to delayed diagnosis of cancer care. RESULTS: Clinicians identified a number of concrete problems and solutions relating to delayed diagnosis of cancer. Raising public awareness, patient education as well as better access to specialist care and diagnostic testing were seen as the highest priorities. The identified suggestions focused mostly on the delays during referrals from primary to secondary care. CONCLUSIONS: Many identified priorities were feasible, affordable and converged around common themes such as public awareness, care continuity and length of consultation. As a timely, proactive and scalable priority-setting approach, PRIORITZE could be implemented as a routine preventative system for determining patient safety issues by frontline staff.

Identification of priorities for improvement of medication safety in primary care: a PRIORITIZE study.

BACKGROUND: Medication error is a frequent, harmful and costly patient safety incident. Research to date has mostly focused on medication errors in hospitals. In this study, we aimed to identify the main causes of, and solutions to, medication error in primary care. METHODS: We used a novel priority-setting method for identifying and ranking patient safety problems and solutions called PRIORITIZE. We invited 500 North West London primary care clinicians to complete an open-ended questionnaire to identify three main problems and solutions relating to medication error in primary care. 113 clinicians submitted responses, which we thematically synthesized into a composite list of 48 distinct problems and 45 solutions. A group of 57 clinicians randomly selected from the initial cohort scored these and an overall ranking was derived. The agreement between the clinicians' scores was presented using the average expert agreement (AEA). The study was conducted between September 2013 and November 2014. RESULTS: The top three problems were incomplete reconciliation of medication during patient 'hand-overs', inadequate patient education about their medication use and poor discharge summaries. The highest ranked solutions included development of a standardized discharge summary template, reduction of unnecessary prescribing, and minimisation of polypharmacy. Overall, better communication between the healthcare provider and patient, quality assurance approaches during medication prescribing and monitoring, and patient education on how to use their medication were considered the top priorities. The highest ranked suggestions received the strongest agreement among the clinicians, i.e. the highest AEA score. CONCLUSIONS: Clinicians identified a range of suggestions for better medication management, quality assurance procedures and patient education. According to clinicians, medication errors can be largely prevented with feasible and affordable interventions. PRIORITIZE is a new, convenient, systematic, and replicable method, and merits further exploration with a view to becoming a part of a routine preventative patient safety monitoring mechanism.

Clinician-identified problems and solutions for delayed diagnosis in primary care: a PRIORITIZE study.

BACKGROUND: Delayed diagnosis in primary care is a common, harmful and costly patient safety incident. Its measurement and monitoring are underdeveloped and underutilised. We created and implemented a novel approach to identify problems leading to and solutions for delayed diagnosis in primary care. METHODS: We developed a novel priority-setting method for patient safety problems and solutions called PRIORITIZE. We invited more than 500 NW London clinicians via an open-ended questionnaire to identify three main problems and solutions relating to delayed diagnosis in primary care. 113 clinicians submitted their suggestions which were thematically grouped and synthesized into a composite list of 33 distinct problems and 27 solutions. A random group of 75 clinicians from the initial cohort scored these and an overall ranking was derived. The agreement between the clinicians' scores was presented using the Average Expert Agreement. RESULTS: The top ranked problems were poor communication between secondary and primary care and the inverse care law, i.e. a mismatch between patients' medical needs and healthcare supply. The highest ranked solutions included: a more rigorous system of communicating abnormal results of investigations to patients, direct hotlines to specialists for GPs to discuss patient problems and better training of primary care clinicians in relevant areas. A priority highlighted throughout the findings is a need to improve communication between clinicians as well as with patients. The highest ranked suggestions had the highest consensus between experts. CONCLUSIONS: The novel method we have developed is highly feasible, informative and scalable, and merits wider exploration with a view of becoming part of a routine pro-active and preventative system for patient safety assessment. Clinicians proposed a range of concrete suggestions with an emphasis on improving communication among clinicians and with patients and better GP training. In their view, delayed diagnosis can be largely prevented with interventions requiring relatively minor investment. Rankings of identified problems and solutions can serve as an aid to policy makers and commissioners of care in prioritization of scarce healthcare resources.

Correction: Capsaicin Treatment Attenuates Cholangiocarcinoma Carcinogenesis.

[This corrects the article DOI: 10.1371/journal.pone.0095605.].

Capsaicin treatment attenuates cholangiocarcinoma carcinogenesis.

UNLABELLED: Capsaicin, the most abundant pungent molecule produced by pepper plants, represents an important ingredient in spicy foods consumed throughout the world. Studies have shown that capsaicin can relieve inflammation and has anti-proliferative effects on various human malignancies. Cholangiocarcinoma (CC) is a cancer disease with rising incidence. The prognosis remains dismal with little advance in treatment. The aim of the present study is to explore the anti-tumor activity of capsaicin in cultured human CC cell lines. Capsaicin effectively impaired cell proliferation, migration, invasion, epithelial to mesenchymal transition and growth of softagar colonies. Further, we show that capsaicin treatment of CC cells regulates the Hedgehog signaling pathway. CONCLUSION: Our results provide a basis for capsaicin to improve the prognosis of CCs in vivo and present new insights into the effectiveness and mode of action of capsaicin.

Combined inhibition of Notch and JAK/STAT is superior to monotherapies and impairs pancreatic cancer progression.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with a high rate of metastasis. Recent studies have indicated that Notch and janus kinase 2 (JAK2)/signal transducers and activators of transcription 3 (STAT3) signaling pathways are both important for the initiation and progression of PDAC. The purpose of this study was to determine the outcome of targeting these two tumor signaling pathways simultaneously both in vitro and in vivo. We assessed the combinational effects of the γ-secretase inhibitor IX (GSI IX) and JAK2 inhibitor (AG-490) on growth and epithelial plasticity of human pancreatic cancer cell lines, and in a genetically engineered mouse model (Pdx1-Cre, LSL-KrasG12D, p53(lox/+)) of PDAC. Dual treatment with GSI IX and AG-490 significantly impaired cell proliferation, migration, invasion, soft agar growth and apoptosis when compared with monotherapies. Most importantly, combinational treatment significantly attenuates tumor progression in vivo and suppresses conversion from acinar-ductal-metaplasia to PDAC. Our results suggest that targeting Notch and JAK2/STAT3 signaling pathways simultaneously is superior to single inhibitions, supporting combined treatment by GSI IX and AG-490 as a potential therapeutic approach for PDAC. However, the study design limits the direct transfer into the clinic and the impact of dual treatment in patients with PDAC remains still to be determined.

Activation of Notch signaling is required for cholangiocarcinoma progression and is enhanced by inactivation of p53 in vivo.

UNLABELLED: Cholangiocacinoma (CC) is a cancer disease with rising incidence. Notch signaling has been shown to be deregulated in many cancers. However, the role of this signaling pathway in the carcinogenesis of CC is still not fully explored. In this study, we investigated the effects of Notch inhibition by γ-secretase inhibitor IX (GSI IX) in cultured human CC cell lines and we established a transgenic mouse model with liver specific expression of the intracellular domain of Notch (Notch-ICD) and inactivation of tumor suppressor p53. GSI IX treatment effectively impaired cell proliferation, migration, invasion, epithelial to mesenchymal transition and growth of softagar colonies. In vivo overexpression of Notch-ICD together with an inactivation of p53 significantly increased tumor burden and showed CC characteristics. CONCLUSION: Our study highlights the importance of Notch signaling in the tumorigenesis of CC and demonstrates that additional inactivation of p53 in vivo.

A critical role for notch signaling in the formation of cholangiocellular carcinomas.

The incidence of cholangiocellular carcinoma (CCC) is increasing worldwide. Using a transgenic mouse model, we found that expression of the intracellular domain of Notch 1 (NICD) in mouse livers results in the formation of intrahepatic CCCs. These tumors display features of bipotential hepatic progenitor cells, indicating that intrahepatic CCC can originate from this cell type. We show that human and mouse CCCs are characterized by high expression of the cyclin E protein and identified the cyclin E gene as a direct transcriptional target of the Notch signaling pathway. Intriguingly, blocking γ-secretase activity in human CCC xenotransplants results in downregulation of cyclin E expression, induction of apoptosis, and tumor remission in vivo.

Inhibition of hedgehog signaling attenuates carcinogenesis in vitro and increases necrosis of cholangiocellular carcinoma.

UNLABELLED: The Hedgehog signaling pathway plays a pivotal role during embryonic development, stem cell maintenance, and wound healing. Hedgehog signaling also is deregulated in many cancers. However, the role of this signaling pathway in the carcinogenesis of cholangiocarcinoma (CCC) is still unknown. In this study, we investigated the effects of Hedgehog inhibition by cyclopamine and 5E1 in cultured human CCC cell lines and in vivo using a xenograft mouse model. We also investigated the involvement of Hedgehog in epithelial to mesenchymal transition (EMT), migration, and CCC tumor growth. Sonic hedgehog (Shh) ligand was highly expressed in 89% of human CCC tissues and in CCC cell lines. Cyclopamine and 5E1 treatments effectively inhibited cell proliferation, migration, and invasion by down-regulating the Hedgehog target genes glioblastoma 1 and glioblastoma 2. In vitro and in vivo, we detected an increase in epithelial marker, E-cadherin, after Hedgehog inhibition. In addition, we saw an increase in necrotic areas and a decrease in mitotic figures in cyclopamine and 5E1-treated CCC xenograft tumors. CONCLUSION: This study supports the presence of autocrine Hedgehog signaling in human CCC, where CCC cells produce and respond to Shh ligand. Blocking the Hedgehog pathway inhibited EMT and decreased the viability of CCC cells. In addition, cyclopamine and 5E1 inhibited the growth of CCC xenograft tumors.

Epithelial mesenchymal transition and pancreatic tumor initiating CD44+/EpCAM+ cells are inhibited by γ-secretase inhibitor IX.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with a high rate of metastasis. Recent studies have indicated that the Notch signalling pathway is important in PDAC initiation and maintenance, although the specific cell biological roles of the pathway remain to be established. Here we sought to examine this question in established pancreatic cancer cell lines using the γ-secretase inhibitor IX (GSI IX) to inactivate Notch. Based on the known roles of Notch in development and stem cell biology, we focused on effects on epithelial mesenchymal transition (EMT) and on pancreatic tumor initiating CD44+/EpCAM+ cells. We analyzed the effect of the GSI IX on growth and epithelial plasticity of human pancreatic cancer cell lines, and on the tumorigenicity of pancreatic tumor initiating CD44+/EpCAM+ cells. Notably, apoptosis was induced after GSI IX treatment and EMT markers were selectively targeted. Furthermore, under GSI IX treatment, decline in the growth of pancreatic tumor initiating CD44+/EpCAM+ cells was observed in vitro and in a xenograft mouse model. This study demonstrates a central role of Notch signalling pathway in pancreatic cancer pathogenesis and identifies an effective approach to inhibit selectively EMT and suppress tumorigenesis by eliminating pancreatic tumor initiating CD44+/EpCAM+ cells.

Decrease of CD44-positive cells correlates with tumor response to chemotherapy in patients with gastrointestinal cancer.

BACKGROUND/AIM: CD44 is a multistructural and multifunctional cell surface molecule which is involved in cell proliferation, differentiation, migration and angiogenesis. Here we investigated the potential role of CD44 in patients with metastasized pancreatic ductal adenocarcinoma, colorectal and stomach cancer, which were treated with different combinations of palliative chemotherapy. PATIENTS AND METHODS: CD44 expression was measured by flow cytometry in patients' (n=15) blood samples and the findings were correlated with CA19-9 expression and with computed tomography results. RESULTS: We found a significant correlation (p<0.05) between the CD44 decrease and the tumor response according to the tumor marker elevation/ response evaluation criteria in solid tumors. CONCLUSION: We were able to monitor changes of CD44 expression after chemotherapy and detected a correlation between the CD44 decrease and the patients' response to treatment. Our findings show that CD44 detection helps to monitor chemotherapy response in patients with gastrointestinal cancer.

Cell death by the quinoxaline dioxide DCQ in human colon cancer cells is enhanced under hypoxia and is independent of p53 and p21.

INTRODUCTION: We have shown that the radio sensitizer DCQ enhances sensitivity of HCT116 human colon cancer cells to hypoxia. However, it is not known whether the p53 or p21 genes influence cellular response to DCQ. In this study, we used HCT116 that are either wildtype for p53 and p21, null for p53 or null for p21 to understand the role of these genes in DCQ toxicity. METHODS: HCT116 cells were exposed to DCQ and incubated under normoxia or hypoxia and the viability, colony forming ability, DNA damage and apoptotic responses of these cells was determined, in addition to the modulation of HIF-1α and of p53, p21, caspase-2, and of the ataxia telangiectasia mutated (ATM) target PIDD-C. RESULTS: DCQ decreased colony forming ability and viability of all HCT116 cells to a greater extent under hypoxia than normoxia and the p21-/-cell line was most sensitive. Cells had different HIF-1α responses to hypoxia and/or drug treatment. In p53+/+, DCQ significantly inhibited the hypoxia-induced increases in HIF-1α protein, in contrast to the absence of a significant HIF-1α increase or modulation by DCQ in p21-/- cells. In p53-/- cells, 10 µM DCQ significantly reduced HIF-1α expression, especially under hypoxia, despite the constitutive expression of this protein in control cells. Higher DCQ doses induced PreG1-phase increase and apoptosis, however, lower doses caused mitotic catastrophe. In p53+/+ cells, apoptosis correlated with the increased expression of the pro-apoptotic caspase-2 and inhibition of the pro-survival protein PIDD-C. Exposure of p53+/+ cells to DCQ induced single strand breaks and triggered the activation of the nuclear kinase ATM by phosphorylation at Ser-1981 in all cell cycle phases. On the other hand, no drug toxicity to normal FHs74 Int human intestinal cell line was observed. CONCLUSIONS: Collectively, our findings indicate that DCQ reduces the colony survival of HCT116 and induces apoptosis even in cells that are null for p53 or p21, which makes it a molecule of clinical significance, since many resistant colon tumors harbor mutations in p53.

Ophthalmic controlled release in situ gelling systems for ciprofloxacin based on polymeric carriers.

The objective of the present study was to design controlled release ophthalmic delivery systems for ciprofloxacin based on polymeric carriers that undergo sol-to-gel transition upon change in pH or in the presence of cations in an attempt to prolong the effect of ciprofloxacin and improve its ocular bioavailability. Carbopol and alginates polymers were used to confer gelation properties to the formulations. Hydroxypropyl methylcellulose and methylcellulose were combined with carbopol to increase the viscosity of the gels and to reduce the concentration of the incorporated carbopol. The release exponents (n) for the designed systems were close to 1, indicating that the drug release occurred by zero-order kinetics. Controlled release in situ gels consisting of carbopol and cellulose derivatives showed an increase in viscosity, gelling capacity, and adhesiveness as the concentration of each polymeric component was increased. On the other hand, these parameters possessed lowest values when alginate was used as an in situ gelling agent. The antimicrobial efficiency of the selected formulation against gram-positive and gram-negative organisms including Echerichia coli, staphylococcus strains and Pseudomonas aeruginosa confirmed that the designed formulation has prolonged the antimicrobial effect of ciprofloxacin and retained its properties against bacteria.

Thermally reversible in situ gelling carbamazepine liquid suppository.

Carbamazepine (CBZ), indicated for the control of epilepsy, undergoes extensive hepatic first-pass elimination after oral administration. A rectal dosage form of CBZ is not commercially available, although it is of particular interest when oral administration is impossible. Conventional suppositories can cause patient discomfort and may reach the end of the colon; consequently, the drug can undergo the first-pass effect. Mucoadhesive liquid suppositories of CBZ were prepared by adding carbopol to formulation of thermally gelling suppositories that contain 20% poloxamer 407 and either 15% poloxamer 188 or 1% methylcellulose. Gellan gum was also tried instead of 20% poloxamer. All formulations contained 10% CBZ. The characteristics of the suppositories differed depending on the formulation. The formula containing 20% poloxamer 407, 1% methylcellulose, and 0.5% carbopol showed reasonable gelation temperature, gel strength and bioadhesive force. The analysis of release mechanism showed that CBZ released from the suppositories by Fickian diffusion. In vivo evaluation of the same formulation showed higher peak plasma concentration of CBZ compared with the orally administered suspension containing the equivalent amount of drug. However, there was no statistical significant difference (p > 0.05) in extent of bioavailability between the liquid suppository and oral suspension as indicated by the values of AUC(0 - infinity), 17.9 and 18.8 micro g x h/ml, respectively. These results suggested that mucoadhesive in situ gelling liquid suppository could be an effective and convenient delivery system of carbamazepine.