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Sample records for preclinical efficacy studies

  1. Pig models of neurodegenerative disorders: Utilization in cell replacement-based preclinical safety and efficacy studies.

    PubMed

    Dolezalova, Dasa; Hruska-Plochan, Marian; Bjarkam, Carsten R; Srensen, Jens Christian H; Cunningham, Miles; Weingarten, David; Ciacci, Joseph D; Juhas, Stefan; Juhasova, Jana; Motlik, Jan; Hefferan, Michael P; Hazel, Tom; Johe, Karl; Carromeu, Cassiano; Muotri, Alysson; Bui, Jack; Strnadel, Jan; Marsala, Martin

    2014-08-15

    An important component for successful translation of cell replacement-based therapies into clinical practice is the utilization of large animal models to conduct efficacy and/or safety cell dosing studies. Over the past few decades, several large animal models (dog, cat, nonhuman primate) were developed and employed in cell replacement studies; however, none of these models appears to provide a readily available platform to conduct effective and large-scale preclinical studies. In recent years, numerous pig models of neurodegenerative disorders were developed using both a transgenic approach as well as invasive surgical techniques. The pig model (nave noninjured animals) was recently used successfully to define the safety and optimal dosing of human spinal stem cells after grafting into the central nervous system (CNS) in immunosuppressed animals. The data from these studies were used in the design of a human clinical protocol used in amyotrophic lateral sclerosis (ALS) patients in a Phase I clinical trial. In addition, a highly inbred (complete major histocompatibility complex [MHC] match) strain of miniature pigs is available which permits the design of comparable MHC combinations between the donor cells and the graft recipient as used in human patients. Jointly, these studies show that the pig model can represent an effective large animal model to be used in preclinical cell replacement modeling. This review summarizes the available pig models of neurodegenerative disorders and the use of some of these models in cell replacement studies. The challenges and potential future directions in more effective use of the pig neurodegenerative models are also discussed. PMID:24610493

  2. Chronic Electrical Stimulation with a Suprachoroidal Retinal Prosthesis: A Preclinical Safety and Efficacy Study

    PubMed Central

    Nayagam, David A. X.; Williams, Richard A.; Allen, Penelope J.; Shivdasani, Mohit N.; Luu, Chi D.; Salinas-LaRosa, Cesar M.; Finch, Sue; Ayton, Lauren N.; Saunders, Alexia L.; McPhedran, Michelle; McGowan, Ceara; Villalobos, Joel; Fallon, James B.; Wise, Andrew K.; Yeoh, Jonathan; Xu, Jin; Feng, Helen; Millard, Rodney; McWade, Melanie; Thien, Patrick C.; Williams, Chris E.; Shepherd, Robert K.

    2014-01-01

    Purpose To assess the safety and efficacy of chronic electrical stimulation of the retina with a suprachoroidal visual prosthesis. Methods Seven normally-sighted feline subjects were implanted for 96–143 days with a suprachoroidal electrode array and six were chronically stimulated for 70–105 days at levels that activated the visual cortex. Charge balanced, biphasic, current pulses were delivered to platinum electrodes in a monopolar stimulation mode. Retinal integrity/function and the mechanical stability of the implant were assessed monthly using electroretinography (ERG), optical coherence tomography (OCT) and fundus photography. Electrode impedances were measured weekly and electrically-evoked visual cortex potentials (eEVCPs) were measured monthly to verify that chronic stimuli were suprathreshold. At the end of the chronic stimulation period, thresholds were confirmed with multi-unit recordings from the visual cortex. Randomized, blinded histological assessments were performed by two pathologists to compare the stimulated and non-stimulated retina and adjacent tissue. Results All subjects tolerated the surgical and stimulation procedure with no evidence of discomfort or unexpected adverse outcomes. After an initial post-operative settling period, electrode arrays were mechanically stable. Mean electrode impedances were stable between 11–15 kΩ during the implantation period. Visually-evoked ERGs & OCT were normal, and mean eEVCP thresholds did not substantially differ over time. In 81 of 84 electrode-adjacent tissue samples examined, there were no discernible histopathological differences between stimulated and unstimulated tissue. In the remaining three tissue samples there were minor focal fibroblastic and acute inflammatory responses. Conclusions Chronic suprathreshold electrical stimulation of the retina using a suprachoroidal electrode array evoked a minimal tissue response and no adverse clinical or histological findings. Moreover, thresholds and electrode impedance remained stable for stimulation durations of up to 15 weeks. This study has demonstrated the safety and efficacy of suprachoroidal stimulation with charge balanced stimulus currents. PMID:24853376

  3. Phase I study and preclinical efficacy evaluation of the mTOR inhibitor sirolimus plus gemcitabine in patients with advanced solid tumours

    PubMed Central

    Martin-Liberal, J; Gil-Martín, M; Sáinz-Jaspeado, M; Gonzalo, N; Rigo, R; Colom, H; Muñoz, C; Tirado, O M; García del Muro, X

    2014-01-01

    Background: We conducted a phase I study in patients with advanced solid tumours to identify the recommended dose, assess pharmacokinetics (PK), pharmacodynamic activity and preclinical antitumour efficacy of the combination of sirolimus and gemcitabine. Methods: Nineteen patients were treated with sirolimus 2 or 5 mg daily and gemcitabine 800 or 1000 mg m−2 on days 1 and 8. Dose escalation depended on dose-limiting toxicity (DLT) rate during the first 3-week period. Paired skin biopsies were evaluated for phosphorylated S6 (pS6) as marker of mTOR (mammalian target of rapamycin) inhibition. Pharmacokinetics and preclinical evaluation of efficacy using two different sarcoma cell lines and leiomyosarcoma xenografts were also conducted. Results: Three DLTs were observed: grade 3 transaminitis, grade 3 thrombocytopenia and grade 4 thrombocytopenia. Common treatment-related adverse events included anaemia, neutropenia, thrombocytopenia and transaminitis. Pharmacodynamic analyses demonstrated mTOR inhibition with sirolimus 5 mg and PK showed no influence of sirolimus concentrations on gemcitabine clearance. In vitro and in vivo studies suggested mTOR pathway hyperactivation by gemcitabine that was reversed by sirolimus. Tumour growth in leiomyosarcoma xenografts was dramatically inhibited by the treatment. Conclusions: Recommended dose was sirolimus 5 mg per 24 h plus gemcitabine 800 mg m−2. Antitumour activity in preclinical sarcoma models and mTOR signalling inhibition were observed. A phase II study is currently ongoing. PMID:25003665

  4. Preclinical Efficacy Testing in Middle-Aged Rats: Nicotinamide, a Novel Neuroprotectant, Demonstrates Diminished Preclinical Efficacy after Controlled Cortical Impact

    PubMed Central

    Swan, Alicia A.; Chandrashekar, Rupa; Beare, Jason

    2011-01-01

    Abstract Age is a consistent predictor of poor outcome following traumatic brain injury (TBI). Although the elderly population has one of the highest rates of TBI-related hospitalization and death, few preclinical studies have attempted to model and treat TBI in the aged population. Recent studies have indicated that nicotinamide (NAM), a soluble B-group vitamin, improved functional recovery in experimental models of TBI in young animals. The purpose of the present study was to examine the preclinical efficacy of NAM in middle-aged rats. Groups of middle-aged (14-month-old) rats were assigned to NAM (500?mg/kg or 50?mg/kg) or saline alone (1?mL/kg) treatment conditions, and received unilateral cortical contusion injuries (CCI) and injections at 1?h and 24?h following injury. The animals were tested on a variety of tasks to assess vestibulomotor (tapered beam) and cognitive performance (reference and working memory in the Morris water maze), and were evaluated for lesion size, bloodbrain barrier compromise, astrocytic activation, and edema formation. In summary, the preclinical efficacy of NAM as a treatment following CCI in middle-aged rats differs from that previously documented in younger rats; while treatment with 50?mg/kg NAM appeared to have no effect, the 500-mg/kg dose worsened performance in middle-aged animals. Histological indicators demonstrated more nuanced group differences, indicating that NAM may positively impact some of the cellular cascades following injury, but were not substantial enough to improve functional recovery. These findings emphasize the need to examine potential treatments for TBI utilizing non-standard populations, and may explain why so many treatments have failed in clinical trials. PMID:21083416

  5. Preclinical safety and efficacy studies with an affinity-enhanced epithelial junction opener and PEGylated liposomal doxorubicin

    PubMed Central

    Richter, Maximilian; Yumul, Roma; Wang, Hongjie; Saydaminova, Kamola; Ho, Martin; May, Drew; Baldessari, Audrey; Gough, Michael; Drescher, Charles; Urban, Nicole; Roffler, Steve; Zubieta, Chloé; Carter, Darrick; Fender, Pascal; Lieber, André

    2015-01-01

    A central treatment resistance mechanism in solid tumors is the maintenance of epithelial junctions between malignant cells that prevent drug penetration into the tumor. We have developed a small recombinant protein (JO-1) that triggers the transient opening of intercellular junctions and thus increases the efficacy of monoclonal antibodies and chemotherapeutic drugs without causing toxicity in mouse tumor models. Here, we provide data toward the clinical translation of an affinity-enhanced version of JO-1, which we call JO-4, in combination with PEGylated liposomal doxorubicin (PLD)/Doxil for ovarian cancer therapy. We have presented X-ray crystallography data suggesting a structural basis for the higher affinity of JO-4 to DSG2. We also confirmed JO-4 efficacy in a xenograft model with primary ovarian cancer cells showing that JO-4 can salvage Doxil therapy when given at a dose that was threefold lower than the therapeutic dose. Furthermore, we tested the safety of intravenous JO-4 alone and in combination with Doxil in Macaca fascicularis, an adequate animal model for predicting toxicity in humans. Our studies did not show critical JO-4-related toxicity or an increase of Doxil-related side effects. Our efficacy and safety data will help to support an Investigational new drug-filing for a JO-4/Doxil combination treatment. PMID:26029716

  6. Efficacy of multiple exposure with low level He-Ne laser dose on acute wound healing: a pre-clinical study

    NASA Astrophysics Data System (ADS)

    Prabhu, Vijendra; Rao, Bola Sadashiva S.; Mahato, Krishna Kishore

    2014-02-01

    Investigations on the use of Low Level Laser Therapy (LLLT) for wound healing especially with the red laser light have demonstrated its pro-healing potential on a variety of pre-clinical and surgical wounds. However, until now, in LLLT the effect of multiple exposure of low dose laser irradiation on acute wound healing on well-designed pre-clinical model is not much explored. The present study aimed to investigate the effect of multiple exposure of low dose Helium Neon laser on healing progression of full thickness excision wounds in Swiss albino mice. Further, the efficacy of the multiple exposure of low dose laser irradiation was compared with the single exposure of optimum dose. Full thickness excision wounds (circular) of 15 mm diameter were created, and subsequently illuminated with the multiple exposures (1, 2, 3, 4 and 5 exposure/ week until healing) of He-Ne (632.8 nm, 4.02 mWcm-2) laser at 0.5 Jcm-2 along with single exposure of optimum laser dose (2 J/cm-2) and un-illuminated controls. Classical biophysical parameters such as contraction kinetics, area under the curve and the mean healing time were documented as the assessment parameters to examine the efficacy of multiple exposures with low level laser dose. Experimental findings substantiated that either single or multiple exposures of 0.5 J/cm2 failed to produce any detectable alterations on wound contraction, area under the curve and mean healing time compared to single exposure of optimum dose (2 Jcm-2) and un-illuminated controls. Single exposure of optimum, laser dose was found to be ideal for acute wound healing.

  7. Allopregnanolone Preclinical Acute Pharmacokinetic and Pharmacodynamic Studies to Predict Tolerability and Efficacy for Alzheimer’s Disease

    PubMed Central

    Irwin, Ronald W.; Solinsky, Christine M.; Loya, Carlos M.; Salituro, Francesco G.; Rodgers, Kathleen E.; Bauer, Gerhard; Rogawski, Michael A.; Brinton, Roberta Diaz

    2015-01-01

    To develop allopregnanolone as a therapeutic for Alzheimer’s disease, we investigated multiple formulations and routes of administration in translationally relevant animal models of both sexes. Subcutaneous, topical (transdermal and intranasal), intramuscular, and intravenous allopregnanolone were bolus-administered. Pharmacokinetic analyses of intravenous allopregnanolone in rabbit and mouse indicated that peak plasma and brain levels (3-fold brain/plasma ratios) at 5min were sufficient to activate neuroregenerative responses at sub-sedative doses. Slow-release subcutaneous suspension of allopregnanolone displayed 5-fold brain/plasma ratio at Cmax at 30min. At therapeutic doses by either subcutaneous or intravenous routes, allopregnanolone mouse plasma levels ranged between 34-51ng/ml by 30min, comparable to published endogenous human level in the third trimester of pregnancy. Exposure to subcutaneous, topical, intramuscular, and intravenous allopregnanolone, at safe and tolerable doses, increased hippocampal markers of neurogenesis including BrdU and PCNA in young 3xTgAD and aged wildtype mice. Intravenous allopregnanolone transiently and robustly phosphorylated CREB within 5min and increased levels of neuronal differentiation transcription factor NeuroD within 4h. Neurogenic efficacy was achieved with allopregnanolone brain exposure of 300-500hr*ng/g. Formulations were tested to determine the no observable adverse effect level (NOAEL) and maximally tolerated doses (MTD) in male and female rats by sedation behavior time course. Sex differences were apparent, males exhibited ≥40% more sedation time compared to females. Allopregnanolone formulated in sulfobutyl-ether-beta-cyclodextrin at optimized complexation ratio maximized allopregnanolone delivery and neurogenic efficacy. To establish the NOAEL and MTD for Allo-induced sedation using a once-per-week intravenous regenerative treatment regimen: In female rats the NOAEL was 0.5mg/kg and MTD 2mg/kg. The predicted MTD in human female is 0.37mg/kg. In male rats the NOAEL and MTD were less than those determined for female. Outcomes of these PK/PD studies predict a safe and efficacious dose range for initial clinical trials of allopregnanolone for Alzheimer’s disease. These findings have translational relevance to multiple neurodegenerative conditions. PMID:26039057

  8. Preclinical assessments of vaginal microbicide candidate safety and efficacy.

    PubMed

    Fernndez-Romero, Jos A; Teleshova, Natalia; Zydowsky, Thomas M; Robbiani, Melissa

    2015-09-15

    Sexually transmitted infections like HIV, HPV, and HSV-2, as well as unplanned pregnancy, take a huge toll on women worldwide. Woman-initiated multipurpose prevention technologies that contain antiviral/antibacterial drugs (microbicides) and a contraceptive to simultaneously target sexually transmitted infections and unplanned pregnancy are being developed to reduce these burdens. This review will consider products that are applied topically to the vagina. Rectally administered topical microbicides in development for receptive anal intercourse are outside the scope of this review. Microbicide and microbicide/contraceptive candidates must be rigorously evaluated in preclinical models of safety and efficacy to ensure that only candidates with favorable risk benefit ratios are advanced into human clinical trials. This review describes the comprehensive set of in vitro, ex vivo, and in vivo models used to evaluate the preclinical safety and antiviral efficacy of microbicide and microbicide/contraceptive candidates. PMID:25543007

  9. Inhibition of DNA-repair genes Ercc1 and Mgmt enhances temozolomide efficacy in gliomas treatment: a pre-clinical study

    PubMed Central

    Boccard, Sandra G.; Marand, Sandie V.; Geraci, Sandra; Pycroft, Laurie; Berger, Franois R.; Pelletier, Laurent A.

    2015-01-01

    Gliomas are the most common primary brain tumors. To date, therapies do not allow curing patients, and glioblastomas (GBMs) are associated with remarkably poor prognosis. This situation is at least partly due to intrinsic or acquired resistance to treatment, especially to chemotherapy. In 2005, temozolomide (TMZ) has become the first chemotherapeutic drug validated for GBM. Nevertheless TMZ efficacy depends on Mgmt status. While the methylation of Mgmt promoter was considered so far as a prognostic marker, its targeting is becoming an effective therapeutic opportunity. Thus, arrival of both TMZ and Mgmt illustrated that considerable progress can still be realized by optimizing adjuvant chemotherapy. A part of this progress could be accomplished in the future by overcoming residual resistance. The aim of the present study was to investigate the involvement of a set of other DNA-repair genes in glioma resistance to temozolomide. We focused on DNA-repair genes located in the commonly deleted chromosomal region in oligodendroglioma (1p/19q) highly correlated with patient response to chemotherapy. We measured effects of inhibition of ten DNA-repair genes expression using siRNAs on astrocytoma cell response to cisplatin (CDDP) and TMZ. SiRNAs targeting ercc1, ercc2, mutyh, and pnkp significantly sensitized cells to chemotherapy, increasing cell death by up to 25%. In vivo we observed a decrease of subcutaneous glioma tumor growth after injection of siRNA in conjunction with absorption of TMZ. We demonstrated in this pre-clinical study that targeting of DNA-repair genes such as Ercc1 could be used as an adjuvant chemosensitization treatment, similarly to Mgmt inhibition. PMID:26336131

  10. A Preclinical Study of the Safety and Efficacy of Occlusin Trade-Mark-Sign 500 Artificial Embolization Device in Sheep

    SciTech Connect

    Owen, Richard J.; Nation, Patrick N.; Polakowski, Robert; Biliske, Jennifer A.; Tiege, Paul B.

    2012-06-15

    Introduction: This study evaluated the safety, effectiveness, and biodegradation of a new embolic agent, Occlusin Trade-Mark-Sign 503 Artificial Embolization Device (OCL 503). The agent consists of biodegradable poly-lactic-co-glycolic acid microspheres (150-212 {mu}m) coated with type I bovine collagen and was compared with Embosphere{sup Registered-Sign} Microspheres (300-500 {mu}m) in this controlled study of uterine artery embolization (UAE) in sheep. Methods: Unilateral UAE was performed in 32 adult ewes randomly assigned. Vessels were embolized to effective stasis. The cohort was divided into four groups, which were sacrificed at 1, 3, 6, and 12 months. Results: Both agents were 100% effective in achieving stasis. At 6 months, all OCL 503-treated arteries were occluded, the microspheres degraded with time, and at 12 months all four animals examined demonstrated recanalization. OCL 503 was found in the untreated uterine artery in one animal with no other evidence of non target embolization. In the Embosphere-treated group, all vessels remained occluded and microspheres were detected in the contralateral uterine artery in 6 of 15 examined vessels and in 10 vaginal, 2 ovarian, and 1 vesical artery. No procedural-related complications were seen in either group. Conclusions: OCL 503 is as effective an embolic agent as Embosphere{sup Registered-Sign} Microspheres when embolizing ovine uterine arteries and resorbs with time, allowing recanalization of the treated arteries. No device-related issues or adverse events were observed.

  11. In-Vivo Efficacy of Compliant 3D Nano-Composite in Critical-Size Bone Defect Repair: a Six Month Preclinical Study in Rabbit

    PubMed Central

    Sagar, Nitin; Pandey, Alok K.; Gurbani, Deepak; Khan, Kainat; Singh, Dhirendra; Chaudhari, Bhushan P.; Soni, Vivek P.; Chattopadhyay, Naibedya; Dhawan, Alok; Bellare, Jayesh R.

    2013-01-01

    Bone defects above critical size do not heal completely by itself and thus represent major clinical challenge to reconstructive surgery. Numerous bone substitutes have already been used to promote bone regeneration, however their use, particularly for critical-sized bone defects along with their long term in vivo safety and efficacy remains a concern. The present study was designed to obtain a complete healing of critical-size defect made in the proximal tibia of New Zealand White rabbit, using nano-hydroxyapatite/gelatin and chemically carboxymethylated chitin (n-HA/gel/CMC) scaffold construct. The bone-implant interfaces and defect site healing was evaluated for a period up to 25 weeks using radiography, micro-computed tomography, fluorescence labeling, and histology and compared with respective SHAM (empty contra lateral control). The viscoelastic porous scaffold construct allows easy surgical insertion and post-operatively facilitate oxygenation and angiogenesis. Radiography of defect treated with scaffold construct suggested expedited healing at defect edges and within the defect site, unlike confined healing at edges of the SHAM sites. The architecture indices analyzed by micro-computed tomography showed a significant increase in percentage of bone volume fraction, resulted in reconciled cortico-trabecular bone formation at n-HA/gel/CMC constructs treated site (15.2% to 52.7%) when compared with respective SHAM (10.2% to 31.8%). Histological examination and fluorescence labeling revealed that the uniformly interconnected porous surface of scaffold construct enhanced osteoblasts activity and mineralization. These preclinical data suggest that, n-HA/gel/CMC construct exhibit stimulation of bone's innate regenerative capacity, thus underscoring their use in guided bone regeneration. PMID:24204879

  12. [Preclinical study of noopept toxicity].

    PubMed

    Kovalenko, L P; Smol'nikova, N M; Alekseeva, S V; Nemova, E P; Sorokina, A V; Miramedova, M G; Kurapova, S P; Sidorina, E I; Kulakova, A V; Daugel'-Dauge, N O

    2002-01-01

    Within the framework of a preclinical investigation, the new nootrope drug noopept (N-phenyl-acetyl-L-propyl-glycine ethylate) was tested for chronic toxicity upon peroral administration in a dose of 10 or 100 mg/kg over 6 months in both male and female rabbits. The results of observations showed that noopept administered in this dose range induced no irreversible pathologic changes in the organs and systems studied and exhibited no allergenic, immunotoxic, and mutagen activity. The drug affected neither the generative function nor the antenatal or postnatal progeny development. Noopept produced a dose-dependent suppression of inflammation reaction to concanavalin A and stimulated the cellular and humoral immune response in mice. PMID:12025790

  13. Efficacy of Pimobendan in the Prevention of Congestive Heart Failure or Sudden Death in Doberman Pinschers with Preclinical Dilated Cardiomyopathy (The PROTECT Study)

    PubMed Central

    Summerfield, NJ; Boswood, A; O'Grady, MR; Gordon, SG; Dukes-McEwan, J; Oyama, MA; Smith, S; Patteson, M; French, AT; Culshaw, GJ; Braz-Ruivo, L; Estrada, A; O'Sullivan, ML; Loureiro, J; Willis, R; Watson, P

    2012-01-01

    Background The benefit of pimobendan in delaying the progression of preclinical dilated cardiomyopathy (DCM) in Dobermans is not reported. Hypothesis That chronic oral administration of pimobendan to Dobermans with preclinical DCM will delay the onset of CHF or sudden death and improve survival. Animals Seventy-six client-owned Dobermans recruited at 10 centers in the UK and North America. Methods The trial was a randomized, blinded, placebo-controlled, parallel group multicenter study. Dogs were allocated in a 1:1 ratio to receive pimobendan (Vetmedin capsules) or visually identical placebo. The composite primary endpoint was prospectively defined as either onset of CHF or sudden death. Time to death from all causes was a secondary endpoint. Results The proportion of dogs reaching the primary endpoint was not significantly different between groups (P = .1). The median time to the primary endpoint (onset of CHF or sudden death) was significantly longer in the pimobendan (718 days, IQR 441–1152 days) versus the placebo group (441 days, IQR 151–641 days) (log-rank P = 0.0088). The median survival time was significantly longer in the pimobendan (623 days, IQR 491–1531 days) versus the placebo group (466 days, IQR 236–710 days) (log-rank P = .034). Conclusion and Clinical Importance The administration of pimobendan to Dobermans with preclinical DCM prolongs the time to the onset of clinical signs and extends survival. Treatment of dogs in the preclinical phase of this common cardiovascular disorder with pimobendan can lead to improved outcome. PMID:23078651

  14. Pre-clinical studies of toxin-specific Nanobodies: Evidence of in vivo efficacy to prevent fatal disturbances provoked by scorpion envenoming

    SciTech Connect

    Hmila, Issam; Cosyns, Bernard; Tounsi, Hayfa; Roosens, Bram; Caveliers, Vicky; Abderrazek, Rahma Ben; Boubaker, Samir; Muyldermans, Serge; Department of Structural Biology, VIB, Brussels ; El Ayeb, Mohamed; Bouhaouala-Zahar, Balkiss; Faculté de Médecine de Tunis, Université de Tunis-El Manar ; Lahoutte, Tony

    2012-10-15

    Scorpions represent a significant threat to humans and animals in various countries throughout the world. Recently, we introduced Nanobodies (Nbs) to combat more efficiently scorpion envenoming and demonstrated the performance of NbAahIF12 and NbAahII10 to neutralize scorpion toxins of Androctonus australis hector venom. A bispecific Nb construct (NbF12-10) comprising these two Nbs is far more protective than the classic Fab′{sub 2} based therapy and is the most efficient antivenom therapy against scorpion sting in preclinical studies. Now we investigate the biodistribution and pharmacokinetics of {sup 99m}Tc labeled Nbs by in vivo imaging in rodents and compared these data with those of the Fab′{sub 2} product (PAS). The pharmacodynamics of the Nbs was investigated in rats by in vivo echocardiography and it is shown that NbF12-10 prevents effectively the hemodynamic disturbances induced by a lethal dose of venom. Moreover, even a late injection of NbF12-10 restores the heart rate and brings the blood pressure to baseline values. Histology confirms that NbF12-10 prevents lung and heart lesions of treated mice after envenoming. In conjunction, in this preclinical study, we provide proof of concept that NbF12-10 prevents effectively the fatal disturbances induced by Androctonus venom, and that the Nanobody based therapeutic has a potential to substitute the classic Fab′{sub 2} based product as immunotherapeutic in scorpion envenoming. Further clinical study using larger cohorts of animals should be considered to confirm the full protecting potential of our NbF12-10. -- Highlights: ► Nanobody therapy prevents the hemodynamic disturbances induced by a lethal dose. ► Late injection of Nanobody restores hemodynamic parameters to baseline values. ► Nanobody therapy prevents lung and heart lesions of treated mice after envenoming. ► Labeled Nanobody and Fab’2 pharmacokinetics curves reach plateau in favour of Nanobody.

  15. Preclinical Studies for Cartilage Repair

    PubMed Central

    Hurtig, Mark B.; Buschmann, Michael D.; Fortier, Lisa A.; Hoemann, Caroline D.; Hunziker, Ernst B.; Jurvelin, Jukka S.; Mainil-Varlet, Pierre; McIlwraith, C. Wayne; Sah, Robert L.; Whiteside, Robert A.

    2011-01-01

    Investigational devices for articular cartilage repair or replacement are considered to be significant risk devices by regulatory bodies. Therefore animal models are needed to provide proof of efficacy and safety prior to clinical testing. The financial commitment and regulatory steps needed to bring a new technology to clinical use can be major obstacles, so the implementation of highly predictive animal models is a pressing issue. Until recently, a reductionist approach using acute chondral defects in immature laboratory species, particularly the rabbit, was considered adequate; however, if successful and timely translation from animal models to regulatory approval and clinical use is the goal, a step-wise development using laboratory animals for screening and early development work followed by larger species such as the goat, sheep and horse for late development and pivotal studies is recommended. Such animals must have fully organized and mature cartilage. Both acute and chronic chondral defects can be used but the later are more like the lesions found in patients and may be more predictive. Quantitative and qualitative outcome measures such as macroscopic appearance, histology, biochemistry, functional imaging, and biomechanical testing of cartilage, provide reliable data to support investment decisions and subsequent applications to regulatory bodies for clinical trials. No one model or species can be considered ideal for pivotal studies, but the larger animal species are recommended for pivotal studies. Larger species such as the horse, goat and pig also allow arthroscopic delivery, and press-fit or sutured implant fixation in thick cartilage as well as second look arthroscopies and biopsy procedures. PMID:26069576

  16. Preclinical Studies of Amixicile, a Systemic Therapeutic Developed for Treatment of Clostridium difficile Infections That Also Shows Efficacy against Helicobacter pylori

    PubMed Central

    Bruce, Alexandra M.; Olekhnovich, Igor; Warren, Cirle A.; Burgess, Stacey L.; Hontecillas, Raquel; Viladomiu, Monica; Bassaganya-Riera, Josep; Guerrant, Richard L.; Macdonald, Timothy L.

    2014-01-01

    Amixicile shows efficacy in the treatment of Clostridium difficile infections (CDI) in a mouse model, with no recurrence of CDI. Since amixicile selectively inhibits the action of a B vitamin (thiamine pyrophosphate) cofactor of pyruvate:ferredoxin oxidoreductase (PFOR), it may both escape mutation-based drug resistance and spare beneficial probiotic gut bacteria that do not express this enzyme. Amixicile is a water-soluble derivative of nitazoxanide (NTZ), an antiparasitic therapeutic that also shows efficacy against CDI in humans. In comparative studies, amixicile showed no toxicity to hepatocytes at 200 μM (NTZ was toxic above 10 μM); was not metabolized by human, dog, or rat liver microsomes; showed equivalence or superiority to NTZ in cytochrome P450 assays; and did not activate efflux pumps (breast cancer resistance protein, P glycoprotein). A maximum dose (300 mg/kg) of amixicile given by the oral or intraperitoneal route was well tolerated by mice and rats. Plasma exposure (rats) based on the area under the plasma concentration-time curve was 79.3 h · μg/ml (30 mg/kg dose) to 328 h · μg/ml (100 mg/kg dose), the maximum concentration of the drug in serum was 20 μg/ml, the time to the maximum concentration of the drug in serum was 0.5 to 1 h, and the half-life was 5.6 h. Amixicile did not concentrate in mouse feces or adversely affect gut populations of Bacteroides species, Firmicutes, segmented filamentous bacteria, or Lactobacillus species. Systemic bioavailability was demonstrated through eradication of Helicobacter pylori in a mouse infection model. In summary, the efficacy of amixicile in treating CDI and other infections, together with low toxicity, an absence of mutation-based drug resistance, and excellent drug metabolism and pharmacokinetic metrics, suggests a potential for broad application in the treatment of infections caused by PFOR-expressing microbial pathogens in addition to CDI. PMID:24890599

  17. Recommendations for Benchmarking Preclinical Studies of Nanomedicines.

    PubMed

    Dawidczyk, Charlene M; Russell, Luisa M; Searson, Peter C

    2015-10-01

    Nanoparticle-based delivery systems provide new opportunities to overcome the limitations associated with traditional small-molecule drug therapy for cancer and to achieve both therapeutic and diagnostic functions in the same platform. Preclinical trials are generally designed to assess therapeutic potential and not to optimize the design of the delivery platform. Consequently, progress in developing design rules for cancer nanomedicines has been slow, hindering progress in the field. Despite the large number of preclinical trials, several factors restrict comparison and benchmarking of different platforms, including variability in experimental design, reporting of results, and the lack of quantitative data. To solve this problem, we review the variables involved in the design of preclinical trials and propose a protocol for benchmarking that we recommend be included in in vivo preclinical studies of drug-delivery platforms for cancer therapy. This strategy will contribute to building the scientific knowledge base that enables development of design rules and accelerates the translation of new technologies. PMID:26249177

  18. Ushering in the study and treatment of preclinical Alzheimer disease.

    PubMed

    Langbaum, Jessica B; Fleisher, Adam S; Chen, Kewei; Ayutyanont, Napatkamon; Lopera, Francisco; Quiroz, Yakeel T; Caselli, Richard J; Tariot, Pierre N; Reiman, Eric M

    2013-07-01

    Researchers have begun to characterize the subtle biological and cognitive processes that precede the clinical onset of Alzheimer disease (AD), and to set the stage for accelerated evaluation of experimental treatments to delay the onset, reduce the risk of, or completely prevent clinical decline. In this Review, we provide an overview of the experimental strategies, and brain imaging and cerebrospinal fluid biomarker measures that are used in early detection and tracking of AD, highlighting at-risk individuals who could be suitable for preclinical monitoring. We discuss how advances in the field have contributed to reconceptualization of AD as a sequence of biological changes that occur during progression from preclinical AD, to mild cognitive impairment and finally dementia, and we review recently proposed research criteria for preclinical AD. Advances in the study of preclinical AD have driven the recognition that efficacy of at least some AD therapies may depend on initiation of treatment before clinical manifestation of disease, leading to a new era of AD prevention research. PMID:23752908

  19. USHERING IN THE STUDY AND TREATMENT OF PRECLINICAL ALZHEIMER DISEASE

    PubMed Central

    Langbaum, Jessica B.S.; Fleisher, Adam S.; Chen, Kewei; Ayutyanont, Napatkamon; Lopera, Francisco; Quiroz, Yakeel T.; Caselli, Richard J.; Tariot, Pierre N.; Reiman, Eric M.

    2014-01-01

    Researchers have begun to characterize the subtle biological and cognitive processes that precede the clinical onset of Alzheimer disease (AD), and to set the stage for accelerated evaluation of experimental treatments to delay the onset, reduce the risk of or completely prevent clinical decline. Here, we provide an overview of the experimental strategies, and brain imaging and cerebrospinal fluid biomarker measures that are used in early detection and tracking of AD, highlighting at-risk individuals who could be suitable for preclinical monitoring. We discuss how these advances have contributed to reconceptualization of AD as a sequence of biological changes that occur during progression from preclinical AD, to mild cognitive impairment and finally dementia, and we review recently proposed research criteria for preclinical AD. Advances in the study of preclinical AD have driven the recognition that efficacy of at least some AD therapies may depend on initiation of treatment before clinical manifestation of disease, leading to a new era of AD prevention research. PMID:23752908

  20. Preclinical studies of a Pro-antibody-drug conjugate designed to selectively target EGFR-overexpressing tumors with improved therapeutic efficacy.

    PubMed

    Yang, Yun; Guo, Qingcheng; Chen, Xi; Zhang, Junjie; Guo, Huaizu; Qian, Weizhu; Hou, Sheng; Dai, Jianxin; Li, Bohua; Guo, Yajun; Wang, Hao

    2016-01-01

    Antibody-drug conjugates (ADCs) have exhibited potent clinical benefits in cancer therapy. However, development of ADCs against epidermal growth factor receptor (EGFR) has limitations because of wide expression of EGFR in both normal and tumor tissues. Previously, we developed an anti-EGFR protease-activated antibody (pro-antibody), termed as PanP, which remains inert against EGFR until activated by tumor-specific protease. Herein, we for the first time report a new class of pro-antibody-drug conjugate (PDC) against EGFR, denoted as PanP-DM1. It has been designed to selectively target the EGFR-overexpressing tumor cells and exert greater anti-tumor activity compared with PanP. Our data showed that PanP-DM1 also could be selectively activated by tumor-specific protease 'uPA'. Furthermore, activated PanP-DM1 was potently cytotoxic against EGFR-overexpressing tumor cell lines in vitro. Crucially, our data indicated that PanP-DM1 was significantly more effective in eradicating EGFR-overexpressing tumors in vivo. Additionally, toxicity was preliminarily evaluated in mice as measured by body weight loss. In summary, our study suggests that PanP-DM1, a novel pro-antibody-drug conjugate, has cancer-selectivity, efficacy and safety profile that supports its potential use for EGFR-overexpressing tumors. PMID:26760045

  1. Preclinical Childhood Sarcoma Models: Drug Efficacy Biomarker Identification and Validation

    PubMed Central

    Geier, Brian; Kurmashev, Dias; Kurmasheva, Raushan T.; Houghton, Peter J.

    2015-01-01

    Over the past 35?years, cure rates for pediatric cancers have increased dramatically. However, it is clear that further dose intensification using cytotoxic agents or radiation therapy is not possible without enhancing morbidity and long-term effects. Consequently, novel, less genotoxic, agents are being sought to complement existing treatments. Here, we discuss preclinical human tumor xenograft models of pediatric cancers that may be used practically to identify novel agents for soft tissue and bone sarcomas, and omics approaches to identifying biomarkers that may identify sensitive and resistant tumors to these agents. PMID:26380223

  2. Antagonistic analogs of growth hormone-releasing hormone increase the efficacy of treatment of triple negative breast cancer in nude mice with doxorubicin; A preclinical study

    PubMed Central

    Perez, Roberto; Schally, Andrew V; Popovics, Petra; Cai, Renzhi; Sha, Wei; Rincon, Ricardo; Rick, Ferenc G.

    2014-01-01

    Introduction This study evaluated the effects of an antagonistic analog of growth hormone-releasing hormone, MIA-602, on tumor growth, response to doxorubicin, expression of drug resistance genes, and efflux pump function in human triple negative breast cancers. Methods HCC1806 (doxorubicin-sensitive) and MX-1 (doxorubicin-resistant), cell lines were xenografted into nude mice and treated with MIA-602, doxorubicin, or their combination. Tumors were evaluated for changes in volume and the expression of the drug resistance genes MDR1 and NANOG. In-vitro cell culture assays were used to analyze the effect of MIA-602 on efflux pump function. Results Therapy with MIA-602 significantly reduced tumor growth and enhanced the efficacy of doxorubicin in both cell lines. Control HCC1806 tumors grew by 435%, while the volume of tumors treated with MIA-602 enlarged by 172.2% and with doxorubicin by 201.6%. Treatment with the combination of MIA-602 and doxorubicin resulted in an increase in volume of only 76.2%. Control MX-1 tumors grew by 907%, while tumors treated with MIA-602 enlarged by 434.8% and with doxorubicin by 815%. The combination of MIA-602 and doxorubicin reduced the increase in tumor volume to 256%. Treatment with MIA-602 lowered the level of growth hormone-releasing hormone and growth hormone-releasing hormone receptors and significantly reduced the expression of multidrug resistance (MDR1) gene and the drug resistance regulator NANOG. MIA-602 also suppressed efflux pump function in both cell lines. Conclusions We conclude that treatment of triple negative breast cancers with growth hormone-releasing hormone antagonists reduces tumor growth and potentiates the effects of cytotoxic therapy by nullifying drug resistance. PMID:25593995

  3. Combination therapy for hepatocellular carcinoma: Additive preclinical efficacy of the HDAC inhibitor panobinostat with sorafenib

    PubMed Central

    Lachenmayer, Anja; Toffanin, Sara; Cabellos, Laia; Alsinet, Clara; Hoshida, Yujin; Villanueva, Augusto; Minguez, Beatriz; Tsai, Hung-Wen; Ward, Stephen C.; Thung, Swan; Friedman, Scott L.; Llovet, Josep M.

    2012-01-01

    Background & Aims Hepatocellular carcinoma (HCC) is a heterogeneous cancer in which sorafenib is the only approved systemic therapy. Histone deacetylases (HDAC) are commonly dysregulated in cancer and therefore represent promising targets for therapies, however their role in HCC pathogenesis is still unknown. We analyzed the expression of 11 HDACs in human HCCs and assessed the efficacy of the pan-HDAC inhibitor panobinostat alone and in combination with sorafenib in preclinical models of liver cancer. Methods Gene expression and copy number changes were analyzed in a cohort of 334 human HCCs, while the effects of panobinostat and sorafenib were evaluated in 3 liver cancer cell lines and a murine xenograft model. Results Aberrant HDAC expression was identified and validated in 91 and 243 HCCs, respectively. Upregulation of HDAC3 and 5 mRNAs were significantly correlated with DNA copy number gains. Inhibiting HDACs with panobinostat led to strong anti-tumoral effects in vitro and vivo, enhanced by the addition of sorafenib. Cell viability and proliferation declined, while apoptosis and autophagy increased. Panobinostat increased Histone H3 and HSP90 acetylation, downregulated BIRC5 (survivin) and upregulated CDH1. Combination therapy with panobinostat and sorafenib significantly decreased vessel density, and most significantly decreased tumor volume and increased survival in HCC xenografts. Conclusions Aberrant expression of several HDACs and copy number gains of HDAC3 and HDAC5 occur in HCC. Treatment with panobinostat combined with sorafenib demonstrated the highest preclinical efficacy in HCC models, providing the rationale for clinical studies with this novel combination. PMID:22322234

  4. [Efficacy studies].

    PubMed

    Pedro-Botet, Juan; Flores-Le Roux, Juana A

    2014-07-01

    Pravafenix(®) is a fixed-dose combination of 40mg of pravastatin and 160 mg of fenofibrate. The rationale behind the use of Pravafenix(®) is based on the increased residual cardiovascular risk observed in high risk patients with hypertriglyceridemia and/or low HDL cholesterol levels despite treatment with statins in monotherapy. In this article, we review the available evidence on the clinical efficacy of Pravafenix(®), which shows complementary benefits in the overall lipid profile of high risk patients with mixed dyslipidemia not controlled with 40-mg pravastatin or 20-mg simvastatin. PMID:25043542

  5. Efficacy of oncolytic adenovirus expressing suicide genes and interleukin-12 in preclinical model of prostate cancer

    PubMed Central

    Freytag, SO; Barton, KN; Zhang, Y

    2013-01-01

    Oncolytic adenovirus-mediated suicide gene therapy has been shown to improve local tumor control in preclinical tumor models and in the clinic. Although local tumor control is important, for most human cancers, new therapies must also target metastatic disease if they are to have an impact on survival. Here, we test the hypothesis that adding cytokine gene therapy to our multimodal platform improves both local and metastatic tumor control in a preclinical model of prostate cancer. An oncolytic adenovirus (Ad5-yCD/mutTKSR39rep-mIL12) expressing two suicide genes and mouse interleukin-12 (IL-12) was generated. Relative to an adenovirus lacking IL-12 (Ad5-yCD/mutTKSR39rep), Ad5-yCD/mutTKSR39rep-mIL12 improved local and metastatic tumor control in the TRAMP-C2 prostate adenocarcinoma model, resulting in a significant increase in survival. Ad5-yCD/mutTKSR39rep-mIL12 resulted in high levels of IL-12 and interferon gamma in serum and tumor, increased natural killer (NK) and cytotoxic T-lymphocyte lytic activities, and the development of tumor-specific antitumor immunity. Immune cell depletion studies indicated that both the innate and adaptive arms of immunity were required for maximal Ad5-yCD/mutTKSR39rep-mIL12 activity. The results demonstrate that the addition of IL-12 significantly improves the efficacy of oncolytic adenovirus-mediated suicide gene therapy and provide the scientific basis for future trials targeting locally aggressive cancers. PMID:23842593

  6. Oncolysis by paramyxoviruses: preclinical and clinical studies

    PubMed Central

    Matveeva, Olga V; Guo, Zong S; Senin, Vyacheslav M; Senina, Anna V; Shabalina, Svetlana A; Chumakov, Peter M

    2015-01-01

    Preclinical studies demonstrate that a broad spectrum of human malignant cells can be killed by oncolytic paramyxoviruses, which include cells of ecto-, endo-, and mesodermal origin. In clinical trials, significant reduction in size or even complete elimination of primary tumors and established metastases are reported. Different routes of viral administration (intratumoral, intravenous, intradermal, intraperitoneal, or intrapleural), and single- versus multiple-dose administration schemes have been explored. The reported side effects are grade 1 and 2, with the most common among them being mild fever. Some advantages in using para-myxoviruses as oncolytic agents versus representatives of other viral families exist. The cytoplasmic replication results in a lack of host genome integration and recombination, which makes paramyxoviruses safer and more attractive candidates for widely used therapeutic oncolysis in comparison with retroviruses or some DNA viruses. The list of oncolytic paramyxovirus representatives includes attenuated measles virus (MV), mumps virus (MuV), low pathogenic Newcastle disease (NDV), and Sendai (SeV) viruses. Metastatic cancer cells frequently overexpress on their surface some molecules that can serve as receptors for MV, MuV, NDV, and SeV. This promotes specific viral attachment to the malignant cell, which is frequently followed by specific viral replication. The paramyxoviruses are capable of inducing efficient syncytium-mediated lyses of cancer cells and elicit strong immunomodulatory effects that dramatically enforce anticancer immune surveillance. In general, preclinical studies and phase 1–3 clinical trials yield very encouraging results and warrant continued research of oncolytic paramyxoviruses as a particularly valuable addition to the existing panel of cancer-fighting approaches. PMID:26640815

  7. A review of preclinical animal models utilised for TB vaccine evaluation in the context of recent human efficacy data?

    PubMed Central

    McShane, Helen; Williams, Ann

    2014-01-01

    Summary There is an urgent need for an improved TB vaccine. Vaccine development is hindered by the lack of immune correlates and uncertain predictive value of preclinical animal models. As data become available from human efficacy trials, there is an opportunity to evaluate the predictive value of the criteria used to select candidate vaccines. Here we review the efficacy in animal models of the MVA85A candidate vaccine in light of recent human efficacy data and propose refinements to the preclinical models with the aim of increasing their predictive value for human efficacy. PMID:24369986

  8. Assessing the preclinical efficacy of antivenoms: from the lethality neutralization assay to antivenomics.

    PubMed

    Gutirrez, Jos Mara; Solano, Gabriela; Pla, Davinia; Herrera, Mara; Segura, lvaro; Villalta, Mauren; Vargas, Maringela; Sanz, Libia; Lomonte, Bruno; Calvete, Juan J; Len, Guillermo

    2013-07-01

    The assessment of the capacity of antivenoms to neutralize the lethal activity of snake venoms is the gold standard in the preclinical analysis of antivenom efficacy, and is routinely performed by manufacturers and quality control laboratories. However, the complexity of snake venom composition and toxicological profile demands that, for many venoms, such as those of viperid snakes and some elapids, the neutralization of lethality be complemented with the analysis of the neutralization of other relevant toxic activities, such as hemorrhagic, myotoxic, necrotizing, procoagulant and defibrinogenating effects. This expanded protocol for preclinical testing of antivenoms should be used when a new antivenom is developed or when an existing antivenom is introduced in a new geographical setting for the neutralization of either homologous or heterologous venoms. In recent years, the assessment of the immunological reactivity of antivenoms has been enriched by the use of proteomic tools, with a methodology named 'antivenomics'. This allows the identification of venom components to which antivenoms have, or lack, antibodies, and thus complements the data gathered in neutralization tests, paving the way for a knowledge-based improvement of antivenom design and efficacy. International projects involving participants of manufacturing, quality control and academic research groups should be promoted in order to gain a deeper understanding on the preclinical neutralizing spectrum of antivenoms. PMID:23201503

  9. Student perception about efficacy of preclinical fixed prosthodontic training to facilitate smooth transition to clinical context

    PubMed Central

    Haralur, Satheesh B.; Al-Malki, Abdullah Edrees

    2014-01-01

    Background: Studies indicate that the initial transition period between preclinical and clinical phases are the most stressful. The students have experienced the difficulty in performing clinical procedures due to the vast difference in the clinical and preclinical setup. It is better to identify the particular skill found poorly correlated, enabling educators to address the concerns. We sought the opinion and suggestion from the beneficiary student on fixed prosthodontics steps difficult to practice in clinical setup at the initial stage, their suggestion to overcome these shortcomings was also sought. Aims: To determine the fixed prosthodontics skills difficult to perform in a transition period due to poor correlation between preclinical and clinical training from our focus group study on the student's perception, and their suggestion regarding alternative methods to improve the preclinical training. Materials and Methods: Focus groups in the study were the students involved in clinical practice of fixed partial denture procedure. A well-constructed Questionnaire, designed to evaluate the difficult clinical steps in a transitional period and suggestion to improve the existing preclinical training was distributed to all focus group students. The response to the questionnaire was based on the five-point Likert scale. Statistical Analysis Used: Medians, frequencies were used to assess their perception on preclinical training and suggestion. Results: A total of 97 students participated in the study, 88% response received during the survey. The clinical steps student felt difficult during a transition period from preclinical to clinical phase were positional variations of teeth (52.6%-63.9%), fluid control (48.5-67.1%), shade selection procedure (29.9%-50.5%), subgingival cervical finish line preparation (38.1-51.5%), and gingival retraction procedure. The students felt that the inclusion of problem-based learning, preclinical patient exposure, and better simulation will alleviate the stress during the transition period. Conclusions: This study highlighted the tooth preparation steps found difficult to practice in a transition period between preclinical and clinical phases. This study also obtained suggestions from the students for innovative upgradation of the course curricula. PMID:25077166

  10. Dissolution DNP for in vivo preclinical studies.

    PubMed

    Comment, Arnaud

    2016-03-01

    The tremendous polarization enhancement afforded by dissolution dynamic nuclear polarization (DNP) can be taken advantage of to perform preclinical in vivo molecular and metabolic imaging. Following the injection of molecules that are hyperpolarized via dissolution DNP, real-time measurements of their biodistribution and metabolic conversion can be recorded. This technology therefore provides a unique and invaluable tool for probing cellular metabolism in vivo in animal models in a noninvasive manner. It gives the opportunity to follow and evaluate disease progression and treatment response without requiring ex vivo destructive tissue assays. Although its considerable potential has now been widely recognized, hyperpolarized magnetic resonance by dissolution DNP remains a challenging method to implement for routine in vivo preclinical measurements. The aim of this article is to provide an overview of the current state-of-the-art technology for preclinical applications and the challenges that need to be addressed to promote it and allow its wider dissemination in the near future. PMID:26920829

  11. Dissolution DNP for in vivo preclinical studies

    NASA Astrophysics Data System (ADS)

    Comment, Arnaud

    2016-03-01

    The tremendous polarization enhancement afforded by dissolution dynamic nuclear polarization (DNP) can be taken advantage of to perform preclinical in vivo molecular and metabolic imaging. Following the injection of molecules that are hyperpolarized via dissolution DNP, real-time measurements of their biodistribution and metabolic conversion can be recorded. This technology therefore provides a unique and invaluable tool for probing cellular metabolism in vivo in animal models in a noninvasive manner. It gives the opportunity to follow and evaluate disease progression and treatment response without requiring ex vivo destructive tissue assays. Although its considerable potential has now been widely recognized, hyperpolarized magnetic resonance by dissolution DNP remains a challenging method to implement for routine in vivo preclinical measurements. The aim of this article is to provide an overview of the current state-of-the-art technology for preclinical applications and the challenges that need to be addressed to promote it and allow its wider dissemination in the near future.

  12. Antidepressant mechanism of ketamine: perspective from preclinical studies

    PubMed Central

    Scheuing, Lisa; Chiu, Chi-Tso; Liao, Hsiao-Mei; Chuang, De-Maw

    2015-01-01

    A debilitating mental disorder, major depressive disorder is a leading cause of global disease burden. Existing antidepressant drugs are not adequate for the majority of depressed patients, and large clinical studies have demonstrated their limited efficacy and slow response onset. Growing evidence of low-dose ketamine's rapid and potent antidepressant effects offers strong potential for future antidepressant agents. However, ketamine has considerable drawbacks such as its abuse potential, psychomimetic effects, and increased oxidative stress in the brain, thus limiting its widespread clinical use. To develop superior antidepressant drugs, it is crucial to better understand ketamine's antidepressant mechanism of action. Recent preclinical studies indicate that ketamine's antidepressant mechanism involves mammalian target of rapamycin pathway activation and subsequent synaptogenesis in the prefrontal cortex, as well as glycogen synthase kinase-3 beta (GSK-3?) inactivation. Adjunct GSK-3? inhibitors, such as lithium, can enhance ketamine's efficacy by augmenting and prolonging its antidepressant effects. Given the potential for depressive relapses, lithium in addition to ketamine is a promising solution for this clinical issue. PMID:26257598

  13. Efficacy of Mesenchymal Stromal Cell Therapy for Acute Lung Injury in Preclinical Animal Models: A Systematic Review.

    PubMed

    McIntyre, Lauralyn A; Moher, David; Fergusson, Dean A; Sullivan, Katrina J; Mei, Shirley H J; Lalu, Manoj; Marshall, John; Mcleod, Malcolm; Griffin, Gilly; Grimshaw, Jeremy; Turgeon, Alexis; Avey, Marc T; Rudnicki, Michael A; Jazi, Mazen; Fishman, Jason; Stewart, Duncan J

    2016-01-01

    The Acute Respiratory Distress Syndrome (ARDS) is a devastating clinical condition that is associated with a 30-40% risk of death, and significant long term morbidity for those who survive. Mesenchymal stromal cells (MSC) have emerged as a potential novel treatment as in pre-clinical models they have been shown to modulate inflammation (a major pathophysiological hallmark of ARDS) while enhancing bacterial clearance and reducing organ injury and death. A systematic search of MEDLINE, EMBASE, BIOSIS and Web of Science was performed to identify pre-clinical studies that examined the efficacy MSCs as compared to diseased controls for the treatment of Acute Lung Injury (ALI) (the pre-clinical correlate of human ARDS) on mortality, a clinically relevant outcome. We assessed study quality and pooled results using random effect meta-analysis. A total of 54 publications met our inclusion criteria of which 17 (21 experiments) reported mortality and were included in the meta-analysis. Treatment with MSCs, as compared to controls, significantly decreased the overall odds of death in animals with ALI (Odds Ratio 0.24, 95% Confidence Interval 0.18-0.34, I2 8%). Efficacy was maintained across different types of animal models and means of ALI induction; MSC origin, source, route of administration and preparation; and the clinical relevance of the model (timing of MSC administration, administration of fluids and or antibiotics). Reporting of standard MSC characterization for experiments that used human MSCs and risks of bias was generally poor, and although not statistically significant, a funnel plot analysis for overall mortality suggested the presence of publication bias. The results from our meta-analysis support that MSCs substantially reduce the odds of death in animal models of ALI but important reporting elements were sub optimal and limit the strength of our conclusions. PMID:26821255

  14. Efficacy of Mesenchymal Stromal Cell Therapy for Acute Lung Injury in Preclinical Animal Models: A Systematic Review

    PubMed Central

    McIntyre, Lauralyn A.; Moher, David; Fergusson, Dean A.; Sullivan, Katrina J.; Mei, Shirley H. J.; Lalu, Manoj; Marshall, John; Mcleod, Malcolm; Griffin, Gilly; Grimshaw, Jeremy; Turgeon, Alexis; Avey, Marc T.; Rudnicki, Michael A.; Jazi, Mazen; Fishman, Jason; Stewart, Duncan J.

    2016-01-01

    The Acute Respiratory Distress Syndrome (ARDS) is a devastating clinical condition that is associated with a 30–40% risk of death, and significant long term morbidity for those who survive. Mesenchymal stromal cells (MSC) have emerged as a potential novel treatment as in pre-clinical models they have been shown to modulate inflammation (a major pathophysiological hallmark of ARDS) while enhancing bacterial clearance and reducing organ injury and death. A systematic search of MEDLINE, EMBASE, BIOSIS and Web of Science was performed to identify pre-clinical studies that examined the efficacy MSCs as compared to diseased controls for the treatment of Acute Lung Injury (ALI) (the pre-clinical correlate of human ARDS) on mortality, a clinically relevant outcome. We assessed study quality and pooled results using random effect meta-analysis. A total of 54 publications met our inclusion criteria of which 17 (21 experiments) reported mortality and were included in the meta-analysis. Treatment with MSCs, as compared to controls, significantly decreased the overall odds of death in animals with ALI (Odds Ratio 0.24, 95% Confidence Interval 0.18–0.34, I2 8%). Efficacy was maintained across different types of animal models and means of ALI induction; MSC origin, source, route of administration and preparation; and the clinical relevance of the model (timing of MSC administration, administration of fluids and or antibiotics). Reporting of standard MSC characterization for experiments that used human MSCs and risks of bias was generally poor, and although not statistically significant, a funnel plot analysis for overall mortality suggested the presence of publication bias. The results from our meta-analysis support that MSCs substantially reduce the odds of death in animal models of ALI but important reporting elements were sub optimal and limit the strength of our conclusions. PMID:26821255

  15. Intravital microscopy as a tool to study drug delivery in preclinical studies

    PubMed Central

    Amornphimoltham, Panomwat; Masedunskas, Andrius; Weigert, Roberto

    2010-01-01

    The technical developments in the field of non-linear microscopy have made intravital microscopy one of the most successful techniques for studying physiological and pathological processes in live animals. Intravital microscopy has been utilized to address many biological questions in basic research and is now a fundamental tool for preclinical studies, with an enormous potential for clinical applications. The ability to dynamically image cellular and subcellular structures combined with the possibility to perform longitudinal studies have empowered investigators to use this discipline to study the mechanisms of action of therapeutic agents and assess the efficacy on their targets in vivo. The goal of this review is to provide a general overview of the recent advances in intravital microscopy and to discuss some of its applications in preclinical studies. PMID:20933026

  16. Preclinical disposition of GDC-0973 and prospective and retrospective analysis of human dose and efficacy predictions.

    PubMed

    Choo, Edna F; Belvin, Marcia; Boggs, Jason; Deng, Yuzhong; Hoeflich, Klaus P; Ly, Justin; Merchant, Mark; Orr, Christine; Plise, Emile; Robarge, Kirk; Martini, Jean F; Kassees, Robert; Aoyama, Ron G; Ramaiya, Atulkumar; Johnston, Stuart H

    2012-05-01

    [3,4-Difluoro-2-(2-fluoro-4-iodo-phenylamino)-phenyl]-((S)-3-hydroxy-3-piperidin-2-yl-azetidin-1-yl)-methanone (GDC-0973) is a potent and highly selective inhibitor of mitogen-activated protein kinase(MAPK)/extracellular signal-regulated kinase (ERK) 1/2 (MEK1/2), a MAPK kinase that activates ERK1/2. The objectives of these studies were to characterize the disposition of GDC-0973 in preclinical species and to determine the relationship of GDC-0973 plasma concentrations to efficacy in Colo205 mouse xenograft models. The clearance (CL) of GDC-0973 was moderate in mouse (33.5 ml min(-1) kg(-1)), rat (37.9 7.2 ml min(-1) kg(-1)), and monkey (29.6 8.5 ml min(-1) kg(-1)). CL in dog was low (5.5 0.3 ml min(-1) kg(-1)). The volume of distribution across species was large, 6-fold to 15-fold body water; half-lives ranged from 4 to 13 h. Protein binding in mouse, rat, dog, monkey, and human was high, with percentage unbound, 1 to 6%. GDC-0973-related radioactivity was rapidly and extensively distributed to tissues; however, low concentrations were observed in the brain. In rats and dogs, [(14)C]GDC-0973 was well absorbed (fraction absorbed, 70-80%). The majority of [(14)C]GDC-0973-related radioactivity was recovered in the bile of rat (74-81%) and dog (65%). The CL and volume of distribution of GDC-0973 in human, predicted by allometry, was 2.9 ml min(-1) kg(-1) and 9.9 l/kg, respectively. The predicted half-life was 39 h. To characterize the relationship between plasma concentration of GDC-0973 and tumor growth inhibition, pharmacokinetic-pharmacodynamic modeling was applied using an indirect response model. The KC(50) value for tumor growth inhibition in Colo205 xenografts was estimated to be 0.389 ?M, and the predicted clinical efficacious dose was ?10 mg. Taken together, these data are useful in assessing the disposition of GDC-0973, and where available, comparisons with human data were made. PMID:22315332

  17. Preclinical Studies for Induced Pluripotent Stem Cell-based Therapeutics*

    PubMed Central

    Harding, John; Mirochnitchenko, Oleg

    2014-01-01

    Induced pluripotent stem cells (iPSCs) and their differentiated derivatives can potentially be applied to cell-based therapy for human diseases. The properties of iPSCs are being studied intensively both to understand the basic biology of pluripotency and cellular differentiation and to solve problems associated with therapeutic applications. Examples of specific preclinical applications summarized briefly in this minireview include the use of iPSCs to treat diseases of the liver, nervous system, eye, and heart and metabolic conditions such as diabetes. Early stage studies illustrate the potential of iPSC-derived cells and have identified several challenges that must be addressed before moving to clinical trials. These include rigorous quality control and efficient production of required cell populations, improvement of cell survival and engraftment, and development of technologies to monitor transplanted cell behavior for extended periods of time. Problems related to immune rejection, genetic instability, and tumorigenicity must be solved. Testing the efficacy of iPSC-based therapies requires further improvement of animal models precisely recapitulating human disease conditions. PMID:24362021

  18. Preclinical Assessment of the Efficacy of Anti-Angiogenic Therapies in Hepatocellular Carcinoma.

    PubMed

    Barral, Matthias; Raballand, Annemila; Dohan, Anthony; Soyer, Philippe; Pocard, Marc; Bonnin, Philippe

    2016-02-01

    Diffuse hepatocellular carcinoma (HCC) is a complex affliction in which comorbidities can bias global outcome of cancer therapy. Better methods are thus warranted to directly assess effects of therapy on tumor angiogenesis and growth. As tumor angiogenesis is invariably associated with changes in local blood flow, we assessed the utility of ultrasound imaging in evaluation of the efficacy of anti-angiogenic therapy in a spontaneous transgenic mouse model of HCC. Blood flow velocities were measured monthly in the celiac trunk before and after administration of sorafenib or bevacizumab at doses corresponding to those currently used in clinical practice. Concordant with clinical experience, sorafenib, but not bevacizumab, reduced microvascular density and suppressed tumor growth relative to controls. Evolution of blood flow velocities correlated with microvascular density and with the evolution of tumor size. Ultrasound imaging thus provides a useful non-invasive tool for preclinical evaluation of new anti-angiogenic therapies for HCC. PMID:26626491

  19. PTEN status mediates 2ME2 anti-tumor efficacy in preclinical glioblastoma models: role of HIF1? suppression.

    PubMed

    Muh, Carrie R; Joshi, Shweta; Singh, Alok R; Kesari, Santosh; Durden, Donald L; Makale, Milan T

    2014-01-01

    Glioblastoma (GBM) is the most common brain cancer and is highly lethal in both adults and children. 2-methoxyestradiol (2ME2) is a microtubule inhibitor that potently inhibits HIF1?, GBM angiogenesis and tumor growth in preclinical models. In patients, 2ME2 exhibits low toxicity and promising but inconsistent efficacy. Given its preclinical potency and its tolerability in patients, we sought to determine whether 2ME2 therapy could be enhanced by addressing resistance via combination therapy, and with biomarkers to identify responsive glioma subgroups. We demonstrate that the PTEN-PI3K axis regulates HIF1? in glioma models. We utilized isogenic-pairs of glioma cell lines, deficient in PTEN or stably reconstituted with PTEN, to determine the role of PTEN in 2ME2 sensitivity in vitro and in vivo. Chou-Talalay synergy studies reveal significant synergy when a pan-PI3K inhibitor is combined with 2ME2. This synergistic activity was correlated with a synergistic suppression of HIF1? accumulation under hypoxic conditions in glioma models. In vivo, 2ME2 markedly inhibited tumor-induced angiogenesis and significantly reduced tumor growth only in a PTEN reconstituted GBM models in both subcutaneous and orthotopic intracranial mouse models. Collectively, these results: (1) suggest that PTEN status predicts sensitivity to 2ME2 and (2) justify exploration of 2ME2 combined with pan-PI3K inhibitors for the treatment of this intractable brain cancer. PMID:24162827

  20. Evaluating the suitability of using rat models for preclinical efficacy and side effects with inhaled corticosteroids nanosuspension formulations.

    PubMed

    Chiang, Po-Chang; Hu, Yiding; Blom, Jason D; Thompson, David C

    2010-01-01

    Inhaled corticosteroids (ICS) are often prescribed as first-line therapy for patients with asthma Despite their efficacy and improved safety profile compared with oral corticosteroids, the potential for systemic side effects continues to cause concern. In order to reduce the potential for systemic side effects, the pharmaceutical industry has begun efforts to generate new drugs with pulmonary-targeted topical efficacy. One of the major challenges of this approach is to differentiate both efficacy and side effects (pulmonary vs. systemic) in a preclinical animal model. In this study, fluticasone and ciclesonide were used as tool compounds to explore the possibility of demonstrating both efficacy and side effects in a rat model using pulmonary delivery via intratracheal (IT) instillation with nanosuspension formulations. The inhibition of neutrophil infiltration into bronchoalveolar lavage fluid (BALF) and cytokine (TNF?) production were utilized to assess pulmonary efficacy, while adrenal and thymus involution as well as plasma corticosterone suppression was measured to assess systemic side effects. Based on neutrophil infiltration and cytokine production data, the ED50s for ciclesonide and fluticasone were calculated to be 0.1 and 0.03 mg, respectively. At the ED50, the average adrenal involution was 7.6 5.3% for ciclesonide versus 16.6 5.1% for fluticasone, while the average thymus involution was 41.0 4.3% for ciclesonide versus 59.5 5.8% for fluticasone. However, the differentiation became less significant when the dose was pushed to the EDmax (0.3 mg for ciclesonide, 0.1 mg for fluticasone). Overall, the efficacy and side effect profiles of the two compounds exhibited differentiation at low to mid doses (0.03-0.1 mg ciclesonide, 0.01-0.03 mg fluticasone), while this differentiation diminished at the maximum efficacious dose (0.3 mg ciclesonide, 0.1 mg fluticasone), likely due to overdosing in this model. We conclude that the rat LPS model using IT administration of nanosuspensions of ICS is a useful tool to demonstrate pulmonary-targeted efficacy and to differentiate the side effects. However, it is only suitable at sub-maximum efficacious levels. PMID:20672144

  1. Evaluating the Suitability of Using Rat Models for Preclinical Efficacy and Side Effects with Inhaled Corticosteroids Nanosuspension Formulations

    NASA Astrophysics Data System (ADS)

    Chiang, Po-Chang; Hu, Yiding; Blom, Jason D.; Thompson, David C.

    2010-06-01

    Inhaled corticosteroids (ICS) are often prescribed as first-line therapy for patients with asthma Despite their efficacy and improved safety profile compared with oral corticosteroids, the potential for systemic side effects continues to cause concern. In order to reduce the potential for systemic side effects, the pharmaceutical industry has begun efforts to generate new drugs with pulmonary-targeted topical efficacy. One of the major challenges of this approach is to differentiate both efficacy and side effects (pulmonary vs. systemic) in a preclinical animal model. In this study, fluticasone and ciclesonide were used as tool compounds to explore the possibility of demonstrating both efficacy and side effects in a rat model using pulmonary delivery via intratracheal (IT) instillation with nanosuspension formulations. The inhibition of neutrophil infiltration into bronchoalveolar lavage fluid (BALF) and cytokine (TNFα) production were utilized to assess pulmonary efficacy, while adrenal and thymus involution as well as plasma corticosterone suppression was measured to assess systemic side effects. Based on neutrophil infiltration and cytokine production data, the ED50s for ciclesonide and fluticasone were calculated to be 0.1 and 0.03 mg, respectively. At the ED50, the average adrenal involution was 7.6 ± 5.3% for ciclesonide versus 16.6 ± 5.1% for fluticasone, while the average thymus involution was 41.0 ± 4.3% for ciclesonide versus 59.5 ± 5.8% for fluticasone. However, the differentiation became less significant when the dose was pushed to the EDmax (0.3 mg for ciclesonide, 0.1 mg for fluticasone). Overall, the efficacy and side effect profiles of the two compounds exhibited differentiation at low to mid doses (0.03-0.1 mg ciclesonide, 0.01-0.03 mg fluticasone), while this differentiation diminished at the maximum efficacious dose (0.3 mg ciclesonide, 0.1 mg fluticasone), likely due to overdosing in this model. We conclude that the rat LPS model using IT administration of nanosuspensions of ICS is a useful tool to demonstrate pulmonary-targeted efficacy and to differentiate the side effects. However, it is only suitable at sub-maximum efficacious levels.

  2. Analgesia in Amphibians: Preclinical Studies and Clinical Applications

    PubMed Central

    Stevens, Craig W.

    2010-01-01

    SYNOPSIS Preclinical studies of analgesia in amphibians or recommendations for clinical use of analgesics in amphibian species are extremely limited. This article briefly reviews the issues surrounding the use of analgesics in amphibians starting with common definitions of pain and analgesia when applied to non-human animals. Nociceptive and endogenous opioid systems in amphibians are reviewed and results of preclinical research on opioid and non-opioid analgesics summarized. Recommended opioid and non-opioid analgesics are summarized and practical recommendations made for their clinical use. PMID:21074701

  3. Preclinical studies of 5-fluoro-2'-deoxycytidine and tetrahydrouridine in pediatric brain tumors.

    PubMed

    Morfouace, Marie; Nimmervoll, Birgit; Boulos, Nidal; Patel, Yogesh T; Shelat, Anang; Freeman, Burgess B; Robinson, Giles W; Wright, Karen; Gajjar, Amar; Stewart, Clinton F; Gilbertson, Richard J; Roussel, Martine F

    2016-01-01

    Chemotherapies active in preclinical studies frequently fail in the clinic due to lack of efficacy, which limits progress for rare cancers since only small numbers of patients are available for clinical trials. Thus, a preclinical drug development pipeline was developed to prioritize potentially active regimens for pediatric brain tumors spanning from in vitro drug screening, through intracranial and intra-tumoral pharmacokinetics to in vivo efficacy studies. Here, as an example of the pipeline, data are presented for the combination of 5-fluoro-2'-deoxycytidine and tetrahydrouridine in three pediatric brain tumor models. The in vitro activity of nine novel therapies was tested against tumor spheres derived from faithful mouse models of Group 3 medulloblastoma, ependymoma, and choroid plexus carcinoma. Agents with the greatest in vitro potency were then subjected to a comprehensive series of in vivo pharmacokinetic (PK) and pharmacodynamic (PD) studies culminating in preclinical efficacy trials in mice harboring brain tumors. The nucleoside analog 5-fluoro-2'-deoxycytidine (FdCyd) markedly reduced the proliferation in vitro of all three brain tumor cell types at nanomolar concentrations. Detailed intracranial PK studies confirmed that systemically administered FdCyd exceeded concentrations in brain tumors necessary to inhibit tumor cell proliferation, but no tumor displayed a significant in vivo therapeutic response. Despite promising in vitro activity and in vivo PK properties, FdCyd is unlikely to be an effective treatment of pediatric brain tumors, and therefore was deprioritized for the clinic. Our comprehensive and integrated preclinical drug development pipeline should reduce the attrition of drugs in clinical trials. PMID:26518542

  4. A cross-laboratory preclinical study on the effectiveness of interleukin-1 receptor antagonist in stroke.

    PubMed

    Maysami, Samaneh; Wong, Raymond; Pradillo, Jesus M; Denes, Adam; Dhungana, Hiramani; Malm, Tarja; Koistinaho, Jari; Orset, Cyrille; Rahman, Mahbubur; Rubio, Marina; Schwaninger, Markus; Vivien, Denis; Bath, Philip M; Rothwell, Nancy J; Allan, Stuart M

    2016-03-01

    Stroke represents a global challenge and is a leading cause of permanent disability worldwide. Despite much effort, translation of research findings to clinical benefit has not yet been successful. Failure of neuroprotection trials is considered, in part, due to the low quality of preclinical studies, low level of reproducibility across different laboratories and that stroke co-morbidities have not been fully considered in experimental models. More rigorous testing of new drug candidates in different experimental models of stroke and initiation of preclinical cross-laboratory studies have been suggested as ways to improve translation. However, to our knowledge, no drugs currently in clinical stroke trials have been investigated in preclinical cross-laboratory studies. The cytokine interleukin 1 is a key mediator of neuronal injury, and the naturally occurring interleukin 1 receptor antagonist has been reported as beneficial in experimental studies of stroke. In the present paper, we report on a preclinical cross-laboratory stroke trial designed to investigate the efficacy of interleukin 1 receptor antagonist in different research laboratories across Europe. Our results strongly support the therapeutic potential of interleukin 1 receptor antagonist in experimental stroke and provide further evidence that interleukin 1 receptor antagonist should be evaluated in more extensive clinical stroke trials. PMID:26661169

  5. A cross-laboratory preclinical study on the effectiveness of interleukin-1 receptor antagonist in stroke

    PubMed Central

    Maysami, Samaneh; Wong, Raymond; Pradillo, Jesus M; Denes, Adam; Dhungana, Hiramani; Malm, Tarja; Koistinaho, Jari; Orset, Cyrille; Rahman, Mahbubur; Rubio, Marina; Schwaninger, Markus; Vivien, Denis; Bath, Philip M; Rothwell, Nancy J

    2015-01-01

    Stroke represents a global challenge and is a leading cause of permanent disability worldwide. Despite much effort, translation of research findings to clinical benefit has not yet been successful. Failure of neuroprotection trials is considered, in part, due to the low quality of preclinical studies, low level of reproducibility across different laboratories and that stroke co-morbidities have not been fully considered in experimental models. More rigorous testing of new drug candidates in different experimental models of stroke and initiation of preclinical cross-laboratory studies have been suggested as ways to improve translation. However, to our knowledge, no drugs currently in clinical stroke trials have been investigated in preclinical cross-laboratory studies. The cytokine interleukin 1 is a key mediator of neuronal injury, and the naturally occurring interleukin 1 receptor antagonist has been reported as beneficial in experimental studies of stroke. In the present paper, we report on a preclinical cross-laboratory stroke trial designed to investigate the efficacy of interleukin 1 receptor antagonist in different research laboratories across Europe. Our results strongly support the therapeutic potential of interleukin 1 receptor antagonist in experimental stroke and provide further evidence that interleukin 1 receptor antagonist should be evaluated in more extensive clinical stroke trials. PMID:26661169

  6. Bridging Translation by Improving Preclinical Study Design in AKI.

    PubMed

    de Caestecker, Mark; Humphreys, Ben D; Liu, Kathleen D; Fissell, William H; Cerda, Jorge; Nolin, Thomas D; Askenazi, David; Mour, Girish; Harrell, Frank E; Pullen, Nick; Okusa, Mark D; Faubel, Sarah

    2015-12-01

    Despite extensive research, no therapeutic interventions have been shown to prevent AKI, accelerate recovery of AKI, or reduce progression of AKI to CKD in patients. This failure in translation has led investigators to speculate that the animal models being used do not predict therapeutic responses in humans. Although this issue continues to be debated, an important concern that has not been addressed is whether improvements in preclinical study design can be identified that might also increase the likelihood of translating basic AKI research into clinical practice using the current models. In this review, we have taken an evidence-based approach to identify common weaknesses in study design and reporting in preclinical AKI research that may contribute to the poor translatability of the findings. We focused on use of N-acetylcysteine or sodium bicarbonate for the prevention of contrast-induced AKI and use of erythropoietin for the prevention of AKI, two therapeutic approaches that have been extensively studied in clinical trials. On the basis of our findings, we identified five areas for improvement in preclinical study design and reporting. These suggested and preliminary guidelines may help improve the quality of preclinical research for AKI drug development. PMID:26538634

  7. Solution Formulation Development and Efficacy of MJC13 in a Preclinical Model of Castrate-Resistant Prostate Cancer

    PubMed Central

    Liang, Su; Bian, Xiaomei; Liang, Dong; Sivils, Jeffrey C.; Neckers, Leonard M.; Cox, Marc B.; Xie, Huan

    2015-01-01

    MJC13, a novel FKBP52 targeting agent, has potential use for the treatment of castrate-resistant prostate cancer. The purpose of this work was to develop a solution formulation of MJC13, and obtain its efficacy profile in a human prostate cancer xenograft mouse model. Preformulation studies were conducted to evaluate the physicochemical properties. Co-solvent systems were evaluated for aqueous solubility and tolerance. A human prostate cancer xenograft mouse model was established by growing 22Rv1 prostate cancer cells in C.B-17 SCID mice. The optimal formulation was used to study the efficacy of MJC13 in this preclinical model of castrate-resistant prostate cancer. We found that MJC13 was stable (at least for 1 month), very lipophilic (logP = 6.49), poorly soluble in water (0.28 μg/mL), and highly plasma protein bound (> 98%). The optimal formulation consisting of PEG 400 and Tween 80 (1:1, v/v) allowed us to achieve a MJC13 concentration of 7.5 mg/mL, and tolerated an aqueous environment. After twice weekly intratumoral injection with 10 mg/kg MJC13 in this formulation for 4 consecutive weeks, tumor volumes were significantly reduced compared to vehicle-treated controls. PMID:25380396

  8. Solution formulation development and efficacy of MJC13 in a preclinical model of castration-resistant prostate cancer.

    PubMed

    Liang, Su; Bian, Xiaomei; Liang, Dong; Sivils, Jeffrey C; Neckers, Leonard M; Cox, Marc B; Xie, Huan

    2016-02-01

    MJC13, a novel FKBP52 targeting agent, has potential use for the treatment of castration-resistant prostate cancer. The purpose of this work was to develop a solution formulation of MJC13, and obtain its efficacy profile in a human prostate cancer xenograft mouse model. Preformulation studies were conducted to evaluate the physicochemical properties. Co-solvent systems were evaluated for aqueous solubility and tolerance. A human prostate cancer xenograft mouse model was established by growing 22Rv1 prostate cancer cells in C.B-17 SCID mice. The optimal formulation was used to study the efficacy of MJC13 in this preclinical model of castrate-resistant prostate cancer. We found that MJC13 was stable (at least for 1 month), highly lipophilic (logP?=?6.49), poorly soluble in water (0.28?g/mL), and highly plasma protein bound (>98%). The optimal formulation consisting of PEG 400 and Tween 80 (1:1, v/v) allowed us to achieve a MJC13 concentration of 7.5?mg/mL, and tolerated an aqueous environment. After twice weekly intratumoral injection with 10?mg/kg MJC13 in this formulation for four consecutive weeks, tumor volumes were significantly reduced compared to vehicle-treated controls. PMID:25380396

  9. A novel CDK9 inhibitor shows potent antitumor efficacy in preclinical hematologic tumor models.

    PubMed

    Yin, Tinggui; Lallena, Maria J; Kreklau, Emiko L; Fales, Kevin R; Carballares, Santiago; Torrres, Raquel; Wishart, Graham N; Ajamie, Rose T; Cronier, Damien M; Iversen, Phillip W; Meier, Timothy I; Foreman, Robert T; Zeckner, Douglas; Sissons, Sean E; Halstead, Bart W; Lin, Aimee B; Donoho, Gregory P; Qian, Yuewei; Li, Shuyu; Wu, Song; Aggarwal, Amit; Ye, Xiang S; Starling, James J; Gaynor, Richard B; de Dios, Alfonso; Du, Jian

    2014-06-01

    DNA-dependent RNA polymerase II (RNAP II) largest subunit RPB1 C-terminal domain (CTD) kinases, including CDK9, are serine/threonine kinases known to regulate transcriptional initiation and elongation by phosphorylating Ser 2, 5, and 7 residues on CTD. Given the reported dysregulation of these kinases in some cancers, we asked whether inhibiting CDK9 may induce stress response and preferentially kill tumor cells. Herein, we describe a potent CDK9 inhibitor, LY2857785, that significantly reduces RNAP II CTD phosphorylation and dramatically decreases MCL1 protein levels to result in apoptosis in a variety of leukemia and solid tumor cell lines. This molecule inhibits the growth of a broad panel of cancer cell lines, and is particularly efficacious in leukemia cells, including orthotopic leukemia preclinical models as well as in ex vivo acute myeloid leukemia and chronic lymphocytic leukemia patient tumor samples. Thus, inhibition of CDK9 may represent an interesting approach as a cancer therapeutic target, especially in hematologic malignancies. PMID:24688048

  10. Humanized cobra venom factor: structure, activity, and therapeutic efficacy in preclinical disease models.

    PubMed

    Vogel, Carl-Wilhelm; Finnegan, Paul W; Fritzinger, David C

    2014-10-01

    The complement system is an integral component of both innate and adaptive immunity. However, complement is also a pathogenetic factor in many diseases. The development of agents for therapeutic complement inhibition is the topic of intense investigations by many investigators. We have developed a distinctly different therapeutic approach: complement depletion rather than inhibition. This approach is based on cobra venom factor (CVF), a C3 analog known to be able to safely deplete complement. This manuscript will briefly review the structure and activity of CVF, along with its similarities and differences to C3. Exploiting the knowledge of the structure/function relationship of CVF and C3, we created derivatives of human C3 which display the CVF-like activity of depleting complement, referred to as humanized CVF (hCVF). This review describes the structure and activity of hCVF, including the important property of not cleaving C5. The efficacy of hCVF for therapeutic complement depletion in nine preclinical models diseases with complement pathology is reviewed, including reperfusion injury, age-related macular degeneration (AMD), paroxysmal nocturnal hemoglobinuria (PNH), and immunogenicity of Factor VIII in hemophilia A. Complement depletion is characterized by the absence of toxicity, even after intra-arterial injection into the pulmonary artery of primates. No immunogenicity has been observed. PMID:25062833

  11. Genetically Engineered Humanized Mouse Models for Preclinical Antibody Studies

    PubMed Central

    Proetzel, Gabriele; Wiles, Michael V.; Roopenian, Derry C.

    2015-01-01

    The use of genetic engineering has vastly improved our capabilities to create animal models relevant in preclinical research. With the recent advances in gene-editing technologies, it is now possible to very rapidly create highly tunable mouse models as needs arise. Here, we provide an overview of genetic engineering methods, as well as the development of humanized neonatal Fc receptor (FcRn) models and their use for monoclonal antibody in vivo studies. PMID:24150980

  12. Extended Preclinical Safety, Efficacy and Stability Testing of a Live-attenuated Chikungunya Vaccine Candidate.

    PubMed

    Plante, Kenneth S; Rossi, Shannan L; Bergren, Nicholas A; Seymour, Robert L; Weaver, Scott C

    2015-09-01

    We recently described a new, live-attenuated vaccine candidate for chikungunya (CHIK) fever, CHIKV/IRES. This vaccine was shown to be well attenuated, immunogenic and efficacious in protecting against CHIK virus (CHIKV) challenge of mice and nonhuman primates. To further evaluate its preclinical safety, we compared CHIKV/IRES distribution and viral loads in interferon-?/? receptor-incompetent A129 mice to another CHIK vaccine candidate, 181/clone25, which proved highly immunogenic but mildly reactive in human Phase I/II clinical trials. Compared to wild-type CHIK virus, (wt-CHIKV), both vaccines generated lower viral loads in a wide variety of tissues and organs, including the brain and leg muscle, but CHIKV/IRES exhibited marked restrictions in dissemination and viral loads compared to 181/clone25, and was never found outside the blood, spleen and muscle. Unlike wt-CHIKV, which caused disrupted splenic architecture and hepatic lesions, histopathological lesions were not observed in animals infected with either vaccine strain. To examine the stability of attenuation, both vaccines were passaged 5 times intracranially in infant A129 mice, then assessed for changes in virulence by comparing parental and passaged viruses for footpad swelling, weight stability and survival after subcutaneous infection. Whereas strain 181/clone25 p5 underwent a significant increase in virulence as measured by weight loss (from <10% to >30%) and mortality (from 0 to 100%), CHIKV/IRES underwent no detectible change in any measure of virulence (no significant weight loss and no mortality). These data indicate greater nonclinical safety of the CHIKV/IRES vaccine candidate compared to 181/clone25, further supporting its eligibility for human testing. PMID:26340754

  13. Extended Preclinical Safety, Efficacy and Stability Testing of a Live-attenuated Chikungunya Vaccine Candidate

    PubMed Central

    Plante, Kenneth S; Rossi, Shannan L.; Bergren, Nicholas A.; Seymour, Robert L.; Weaver, Scott C.

    2015-01-01

    We recently described a new, live-attenuated vaccine candidate for chikungunya (CHIK) fever, CHIKV/IRES. This vaccine was shown to be well attenuated, immunogenic and efficacious in protecting against CHIK virus (CHIKV) challenge of mice and nonhuman primates. To further evaluate its preclinical safety, we compared CHIKV/IRES distribution and viral loads in interferon-α/β receptor-incompetent A129 mice to another CHIK vaccine candidate, 181/clone25, which proved highly immunogenic but mildly reactive in human Phase I/II clinical trials. Compared to wild-type CHIK virus, (wt-CHIKV), both vaccines generated lower viral loads in a wide variety of tissues and organs, including the brain and leg muscle, but CHIKV/IRES exhibited marked restrictions in dissemination and viral loads compared to 181/clone25, and was never found outside the blood, spleen and muscle. Unlike wt-CHIKV, which caused disrupted splenic architecture and hepatic lesions, histopathological lesions were not observed in animals infected with either vaccine strain. To examine the stability of attenuation, both vaccines were passaged 5 times intracranially in infant A129 mice, then assessed for changes in virulence by comparing parental and passaged viruses for footpad swelling, weight stability and survival after subcutaneous infection. Whereas strain 181/clone25 p5 underwent a significant increase in virulence as measured by weight loss (from <10% to >30%) and mortality (from 0 to 100%), CHIKV/IRES underwent no detectible change in any measure of virulence (no significant weight loss and no mortality). These data indicate greater nonclinical safety of the CHIKV/IRES vaccine candidate compared to 181/clone25, further supporting its eligibility for human testing. PMID:26340754

  14. Preclinical profile of a potent gamma-secretase inhibitor targeting notch signaling with in vivo efficacy and pharmacodynamic properties.

    PubMed

    Luistro, Leopoldo; He, Wei; Smith, Melissa; Packman, Kathryn; Vilenchik, Maria; Carvajal, Daisy; Roberts, John; Cai, James; Berkofsky-Fessler, Windy; Hilton, Holly; Linn, Michael; Flohr, Alexander; Jakob-Røtne, Roland; Jacobsen, Helmut; Glenn, Kelli; Heimbrook, David; Boylan, John F

    2009-10-01

    Notch signaling is an area of great interest in oncology. RO4929097 is a potent and selective inhibitor of gamma-secretase, producing inhibitory activity of Notch signaling in tumor cells. The RO4929097 IC50 in cell-free and cellular assays is in the low nanomolar range with >100-fold selectivity with respect to 75 other proteins of various types (receptors, ion channels, and enzymes). RO4929097 inhibits Notch processing in tumor cells as measured by the reduction of intracellular Notch expression by Western blot. This leads to reduced expression of the Notch transcriptional target gene Hes1. RO4929097 does not block tumor cell proliferation or induce apoptosis but instead produces a less transformed, flattened, slower-growing phenotype. RO4929097 is active following oral dosing. Antitumor activity was shown in 7 of 8 xenografts tested on an intermittent or daily schedule in the absence of body weight loss or Notch-related toxicities. Importantly, efficacy is maintained after dosing is terminated. Angiogenesis reverse transcription-PCR array data show reduced expression of several key angiogenic genes. In addition, comparative microarray analysis suggests tumor cell differentiation as an additional mode of action. These preclinical results support evaluation of RO4929097 in clinical studies using an intermittent dosing schedule. A multicenter phase I dose escalation study in oncology is under way. PMID:19773430

  15. ChimeriVax-West Nile Virus Live-Attenuated Vaccine: Preclinical Evaluation of Safety, Immunogenicity, and Efficacy

    PubMed Central

    Arroyo, Juan; Miller, Chuck; Catalan, John; Myers, Gwendolyn A.; Ratterree, Marion S.; Trent, Dennis W.; Monath, Thomas P.

    2004-01-01

    The availability of ChimeriVax vaccine technology for delivery of flavivirus protective antigens at the time West Nile (WN) virus was first detected in North America in 1999 contributed to the rapid development of the vaccine candidate against WN virus described here. ChimeriVax-Japanese encephalitis (JE), the first live- attenuated vaccine developed with this technology has successfully undergone phase I and II clinical trials. The ChimeriVax technology utilizes yellow fever virus (YF) 17D vaccine strain capsid and nonstructural genes to deliver the envelope gene of other flaviviruses as live-attenuated chimeric viruses. Amino acid sequence homology between the envelope protein (E) of JE and WN viruses facilitated targeting attenuating mutation sites to develop the WN vaccine. Here we discuss preclinical studies with the ChimeriVax-WN virus in mice and macaques. ChimeriVax-WN virus vaccine is less neurovirulent than the commercial YF 17D vaccine in mice and nonhuman primates. Attenuation of the virus is determined by the chimeric nature of the construct containing attenuating mutations in the YF 17D virus backbone and three point mutations introduced to alter residues 107, 316, and 440 in the WN virus E protein gene. The safety, immunogenicity, and efficacy of the ChimeriVax-WN02 vaccine in the macaque model indicate the vaccine candidate is expected to be safe and immunogenic for humans. PMID:15507637

  16. Preclinical safety and efficacy models for pulmonary drug delivery of antimicrobials with focus on in vitro models.

    PubMed

    Hittinger, Marius; Juntke, Jenny; Kletting, Stephanie; Schneider-Daum, Nicole; de Souza Carvalho, Cristiane; Lehr, Claus-Michael

    2015-05-01

    New pharmaceutical formulations must be proven as safe and effective before entering clinical trials. Also in the context of pulmonary drug delivery, preclinical models allow testing of novel antimicrobials, reducing risks and costs during their development. Such models allow reducing the complexity of the human lung, but still need to reflect relevant (patho-) physiological features. This review focuses on preclinical pulmonary models, mainly in vitro models, to assess drug safety and efficacy of antimicrobials. Furthermore, approaches to investigate common infectious diseases of the respiratory tract, are emphasized. Pneumonia, tuberculosis and infections occurring due to cystic fibrosis are in focus of this review. We conclude that especially in vitro models offer the chance of an efficient and detailed analysis of new antimicrobials, but also draw attention to the advantages and limitations of such currently available models and critically discuss the necessary steps for their future development. PMID:25453270

  17. A preclinical study on the combination therapy of everolimus and transarterial chemoembolization in hepatocellular carcinoma.

    PubMed

    Chow, Ariel Km; Yau, Thomas Cc; Ng, Lui; Chu, Andrew Cy; Law, Wai-Lun; Poon, Ronnie Tp; Pang, Roberta Wc

    2015-01-01

    Transarterial chemoembolization (TACE) is commonly used for the treatment of locally advanced hepatocellular carcinoma (HCC) by its dual effects of chemotherapy and ischemic hypoxia. However, one of the side effects of TACE is the introduction of hypoxic condition, which in turn activates hypoxia-induced survival pathways and enhances VEGF-induced neovascularization by stabilizing HIF-1? expression. Herein, the preclinical therapeutic efficacy of the combined treatment of everolimus, a novel mTOR inhibitor and TACE for the treatment of HCC was investigated. The MHCC-97L cells were used for the study of the effect of combined treatment on cell proliferation and cellular apoptosis. HUVEC cells were used for the study on tube formation under different treatments. Inhibitions on the Akt/mTOR pathways were also studied. Finally, the effect on tumor growth was further study using an in vivo orthotopic model. The results demonstrated that everolimus enhanced the therapeutic efficacy of TACE in inhibiting cell proliferation, promoting apoptosis and inhibiting tube formation of endothelial cells by blocking the Akt/mTOR signaling pathway in vitro and inhibiting tumor growth and neoangiogenesis in vivo. Based on this preclinical study, the potential of combining everolimus with TACE was guaranteed which suggested the use of the combination therapy in the clinical treatment of advanced HCC patients. PMID:26396913

  18. A preclinical study on the combination therapy of everolimus and transarterial chemoembolization in hepatocellular carcinoma

    PubMed Central

    Chow, Ariel KM; Yau, Thomas CC; Ng, Lui; Chu, Andrew CY; Law, Wai-Lun; Poon, Ronnie TP; Pang, Roberta WC

    2015-01-01

    Transarterial chemoembolization (TACE) is commonly used for the treatment of locally advanced hepatocellular carcinoma (HCC) by its dual effects of chemotherapy and ischemic hypoxia. However, one of the side effects of TACE is the introduction of hypoxic condition, which in turn activates hypoxia-induced survival pathways and enhances VEGF-induced neovascularization by stabilizing HIF-1? expression. Herein, the preclinical therapeutic efficacy of the combined treatment of everolimus, a novel mTOR inhibitor and TACE for the treatment of HCC was investigated. The MHCC-97L cells were used for the study of the effect of combined treatment on cell proliferation and cellular apoptosis. HUVEC cells were used for the study on tube formation under different treatments. Inhibitions on the Akt/mTOR pathways were also studied. Finally, the effect on tumor growth was further study using an in vivo orthotopic model. The results demonstrated that everolimus enhanced the therapeutic efficacy of TACE in inhibiting cell proliferation, promoting apoptosis and inhibiting tube formation of endothelial cells by blocking the Akt/mTOR signaling pathway in vitro and inhibiting tumor growth and neoangiogenesis in vivo. Based on this preclinical study, the potential of combining everolimus with TACE was guaranteed which suggested the use of the combination therapy in the clinical treatment of advanced HCC patients. PMID:26396913

  19. Exploring Polymeric Micelles for Improved Delivery of Anticancer Agents: Recent Developments in Preclinical Studies

    PubMed Central

    Tan, Chalet; Wang, Yingzhe; Fan, Wei

    2013-01-01

    As versatile drug delivery systems, polymeric micelles have demonstrated particular strength in solubilizing hydrophobic anticancer drugs while eliminating the use of toxic organic solvents and surfactants. However, the true promise of polymeric micelles as drug carriers for cancer therapy resides in their potential ability to preferentially elevate drug exposure in the tumor and achieve enhanced anticancer efficacy, which still remains to be fully exploited. Here, we review various micellar constructs that exhibit the enhanced permeation and retention effect in the tumor, the targeting ligands that potentiate the anticancer efficacy of micellar drugs, and the polyplex micelle systems suitable for the delivery of plasmid DNA and small interference RNA. Together, these preclinical studies in animal models help us further explore polymeric micelles as emerging drug carriers for targeted cancer therapy. PMID:24300405

  20. Pharmacological Intervention Studies Using Mouse Models of the Inflammatory Bowel Diseases: Translating Preclinical Data into New Drug Therapies

    PubMed Central

    Koboziev, Iurii; Karlsson, Fridrik; Zhang, Songlin; Grisham, Matthew B.

    2010-01-01

    Most therapeutic agents used in clinical practice today were originally developed and tested in animal models so that drug toxicity and safety, dose-responses and efficacy could be determined. Retrospective analyses of preclinical intervention studies using animal models of different diseases demonstrate that only a small percentage of the interventions reporting promising effects translate to clinical efficacy. The failure to translate therapeutic efficacy from bench to bedside may be due, in part, to shortcomings in the design of the clinical studies; however, it is becoming clear that much of the problem resides within the preclinical studies. One potential strategy for improving our ability to identify new therapeutics that may have a reasonable chance of success in well-controlled clinical trials is to identify the most relevant mouse models IBD and pharmacologic strategies that most closely mimic the clinical situation. To begin this process, we present a critical evaluation of the different mouse models and pharmacological approaches that may be used in intervention studies as well as discuss emerging issues related to study design and data interpretation of preclinical studies. PMID:21312318

  1. Experimental design and efficient parameter estimation in preclinical pharmacokinetic studies.

    PubMed

    Ette, E I; Howie, C A; Kelman, A W; Whiting, B

    1995-05-01

    Monte Carlo simulation technique used to evaluate the effect of the arrangement of concentrations on the efficiency of estimation of population pharmacokinetic parameters in the preclinical setting is described. Although the simulations were restricted to the one compartment model with intravenous bolus input, they provide the basis of discussing some structural aspects involved in designing a destructive ("quantic") preclinical population pharmacokinetic study with a fixed sample size as is usually the case in such studies. The efficiency of parameter estimation obtained with sampling strategies based on the three and four time point designs were evaluated in terms of the percent prediction error, design number, individual and joint confidence intervals coverage for parameter estimates approaches, and correlation analysis. The data sets contained random terms for both inter- and residual intra-animal variability. The results showed that the typical population parameter estimates for clearance and volume were efficiently (accurately and precisely) estimated for both designs, while interanimal variability (the only random effect parameter that could be estimated) was inefficiently (inaccurately and imprecisely) estimated with most sampling schedules of the two designs. The exact location of the third and fourth time point for the three and four time point designs, respectively, was not critical to the efficiency of overall estimation of all population parameters of the model. However, some individual population pharmacokinetic parameters were sensitive to the location of these times. PMID:7479560

  2. Immunotherapy with dendritic cells loaded with glioblastoma stem cells: from preclinical to clinical studies.

    PubMed

    Finocchiaro, Gaetano; Pellegatta, Serena

    2016-01-01

    Different approaches have been explored to raise effective antitumor responses against glioblastoma (GBM), the deadliest of primary brain tumors. In many clinical studies, cancer vaccines have been based on dendritic cells (DCs) loaded with peptides, representing one or more specific tumor antigens or whole lysates as a source of multiple antigens. Randomized clinical trials using DCs are ongoing, and results of efficacy are not yet available. Such strategies are feasible and safe; however, immune-suppressive microenvironment, absence of appropriate specific epitopes to target, and cancer immunoediting can limit their efficacy. The aim of this review is to describe how the definition of novel and more specific targets may increase considerably the possibility of successful DC immunotherapy. By proposing to target glioblastoma stem-like cells (GSCs), the immune response will be pointed to eradicating factors and pathways highly relevant to GBM biology. Preclinical observations on efficacy, and preliminary results of immunotherapy trials, encourage exploring the clinical efficacy of DC immunotherapy in GBM patients using high-purity, GSC-loaded DC vaccines. PMID:26377689

  3. Resveratrol: A review of preclinical studies for human cancer prevention

    SciTech Connect

    Athar, Mohammad; Back, Jung Ho; Tang Xiuwei; Kim, Kwang Ho; Kopelovich, Levy; Bickers, David R.; Kim, Arianna L.

    2007-11-01

    The search for novel and effective cancer chemopreventive agents has led to the identification of various naturally occurring compounds one of which is resveratrol (trans-3,4',5-trihydroxystilbene), a phytoalexin derived from the skin of grapes and other fruits. Resveratrol is known to have potent anti-inflammatory and antioxidant effects and to inhibit platelet aggregation and the growth of a variety of cancer cells. Its potential chemopreventive and chemotherapeutic activities have been demonstrated in all three stages of carcinogenesis (initiation, promotion, and progression), in both chemically and UVB-induced skin carcinogenesis in mice, as well as in various murine models of human cancers. Evidence from numerous in vitro and in vivo studies has confirmed its ability to modulate various targets and signaling pathways. This review discusses the current preclinical and mechanistic data available and assesses resveratrol's anticancer effects to support its potential as an anticancer agent in human populations.

  4. Effect of soy isoflavones on the growth of human breast tumors: findings from preclinical studies

    PubMed Central

    Kwon, Youngjoo

    2014-01-01

    Breast cancer is the most common cancer among women worldwide, and many women with breast cancer live more than 5years after their diagnosis. Breast cancer patients and survivors have a greater interest in taking soy foods and isoflavone supplements. However, the effect of isoflavones on breast cancer remains controversial. Thus, it is critical to determine if and when isoflavones are beneficial or detrimental to breast cancer patients. According to the available preclinical data, high concentrations of isoflavones inhibit the proliferation of breast cancer cells, regardless of their estrogen receptor (ER) status. In comparison, genistein, a major isoflavone, has stimulated tumor growth at low concentrations and mitigated tamoxifen efficacy in ER-positive breast cancer. Studies have indicated that the relative levels of genistein and estrogen at the target site are important to determine the genistein effect on the ER-positive tumor growth. However, studies using ovariectomized mice and subcutaneous xenograft models might not truly reflect estrogen concentrations in human breast tumors. Moreover, it may be an oversimplification that isoflavones stimulate hormone-dependent tumor growth due to their potential estrogenic effect since studies also suggest nonestrogenic anticancer effects of isoflavones and ER-independent anticancer activity of tamoxifen. Therefore, the concentrations of isoflavones and estrogen in human breast tumors should be considered better in future preclinical studies and the parameters that can estimate those levels in breast tumors are required in human clinical/epidemiological investigation. In addition, it will be important to identify the molecular mechanisms that either inhibit or promote the growth of breast cancer cells by soy isoflavones, and use those molecules to evaluate the relevance of the preclinical findings to the human disease and to predict the health effects of isoflavones in human breast tumors. PMID:25493176

  5. Novel Epigenetic Target Therapy for Prostate Cancer: A Preclinical Study

    PubMed Central

    Gherardini, Lisa; Pelosi, Gualtiero; Viglione, Federica; Grimaldi, Settimio; Pani, Luca; Cinti, Caterina

    2014-01-01

    Epigenetic events are critical contributors to the pathogenesis of cancer, and targeting epigenetic mechanisms represents a novel strategy in anticancer therapy. Classic demethylating agents, such as 5-Aza-2′-deoxycytidine (Decitabine), hold the potential for reprograming somatic cancer cells demonstrating high therapeutic efficacy in haematological malignancies. On the other hand, epigenetic treatment of solid tumours often gives rise to undesired cytotoxic side effects. Appropriate delivery systems able to enrich Decitabine at the site of action and improve its bioavailability would reduce the incidence of toxicity on healthy tissues. In this work we provide preclinical evidences of a safe, versatile and efficient targeted epigenetic therapy to treat hormone sensitive (LNCap) and hormone refractory (DU145) prostate cancers. A novel Decitabine formulation, based on the use of engineered erythrocyte (Erythro-Magneto-Hemagglutinin Virosomes, EMHVs) drug delivery system (DDS) carrying this drug, has been refined. Inside the EMHVs, the drug was shielded from the environment and phosphorylated in its active form. The novel magnetic EMHV DDS, endowed with fusogenic protein, improved the stability of the carried drug and exhibited a high efficiency in confining its delivery at the site of action in vivo by applying an external static magnetic field. Here we show that Decitabine loaded into EMHVs induces a significant tumour mass reduction in prostate cancer xenograft models at a concentration, which is seven hundred times lower than the therapeutic dose, suggesting an improved pharmacokinetics/pharmacodynamics of drug. These results are relevant for and discussed in light of developing personalised autologous therapies and innovative clinical approach for the treatment of solid tumours. PMID:24851905

  6. Preclinical Development and In Vivo Efficacy of Ceftiofur-PLGA Microparticles.

    PubMed

    Vilos, Cristian; Velasquez, Luis A; Rodas, Paula I; Zepeda, Katherine; Bong, Soung-Jae; Herrera, Natalia; Cantin, Mario; Simon, Felipe; Constandil, Luis

    2015-01-01

    Drug delivery systems based on polymeric microparticles represent an interesting field of development for the treatment of several infectious diseases for humans and animals. In this work, we developed PLGA microparticles loaded with ceftiofur (PLGA-cef), a third- generation cephalosporin that is used exclusively used in animals. PLGA-cef was prepared by the double emulsion w/o/w method, and exhibited a diameter in the range of 1.5-2.2 ?m, and a negative ? potential in the range of -35 to -55 mV. The loading yield of PLGA-cef was ~7% and encapsulation efficiency was approximately 40%. The pharmacokinetic study demonstrated a sustained release profile of ceftiofur for 20 days. PLGA-cef administrated in a single dose was more effective than ceftiofur non-encapsulated in rats challenged with S. Typhimurium. The in vivo toxicological evaluation showed that PLGA-cef did not affect the blood biochemical, hematological and hemostasis parameters. Overall, the PLGA-cef showed slow in vivo release profile, high antibacterial efficacy, and low toxicity. The results obtained supports the safe application of PLGA-cef as sustained release platform in the veterinary industry. PMID:25915043

  7. Tailored Pig Models for Preclinical Efficacy and Safety Testing of Targeted Therapies.

    PubMed

    Klymiuk, Nikolai; Seeliger, Frank; Bohlooly-Y, Mohammad; Blutke, Andreas; Rudmann, Daniel G; Wolf, Eckhard

    2016-04-01

    Despite enormous advances in translational biomedical research, there remains a growing demand for improved animal models of human disease. This is particularly true for diseases where rodent models do not reflect the human disease phenotype. Compared to rodents, pig anatomy and physiology are more similar to humans in cardiovascular, immune, respiratory, skeletal muscle, and metabolic systems. Importantly, efficient and precise techniques for genetic engineering of pigs are now available, facilitating the creation of tailored large animal models that mimic human disease mechanisms at the molecular level. In this article, the benefits of genetically engineered pigs for basic and translational research are exemplified by a novel pig model of Duchenne muscular dystrophy and by porcine models of cystic fibrosis. Particular emphasis is given to potential advantages of using these models for efficacy and safety testing of targeted therapies, such as exon skipping and gene editing, for example, using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system. In general, genetically tailored pig models have the potential to bridge the gap between proof-of-concept studies in rodents and clinical trials in patients, thus supporting translational medicine. PMID:26511847

  8. Preclinical Development and In Vivo Efficacy of Ceftiofur-PLGA Microparticles

    PubMed Central

    Vilos, Cristian; Velasquez, Luis A.; Rodas, Paula I.; Zepeda, Katherine; Bong, Soung-Jae; Herrera, Natalia; Cantin, Mario; Simon, Felipe; Constandil, Luis

    2015-01-01

    Drug delivery systems based on polymeric microparticles represent an interesting field of development for the treatment of several infectious diseases for humans and animals. In this work, we developed PLGA microparticles loaded with ceftiofur (PLGA-cef), a third- generation cephalosporin that is used exclusively used in animals. PLGA-cef was prepared by the double emulsion w/o/w method, and exhibited a diameter in the range of 1.5–2.2 μm, and a negative ζ potential in the range of -35 to -55 mV. The loading yield of PLGA-cef was ~7% and encapsulation efficiency was approximately 40%. The pharmacokinetic study demonstrated a sustained release profile of ceftiofur for 20 days. PLGA-cef administrated in a single dose was more effective than ceftiofur non-encapsulated in rats challenged with S. Typhimurium. The in vivo toxicological evaluation showed that PLGA-cef did not affect the blood biochemical, hematological and hemostasis parameters. Overall, the PLGA-cef showed slow in vivo release profile, high antibacterial efficacy, and low toxicity. The results obtained supports the safe application of PLGA-cef as sustained release platform in the veterinary industry. PMID:25915043

  9. Preclinical efficacy of thioxanthone SR271425 against transplanted solid tumors of mouse and human origin.

    PubMed

    Corbett, T H; Panchapor, C; Polin, L; Lowichik, N; Pugh, S; White, K; Kushner, J; Meyer, J; Czarnecki, J; Chinnukroh, S; Edelstein, M; LoRusso, P; Heilbrun, L; Horwitz, J P; Grieshaber, C; Perni, R; Wentland, M; Coughlin, S; Elenbaas, S; Philion, R; Rake, J

    1999-01-01

    A highly active and broadly active thioxanthone has been identified: N-[[1-[[2-(Diethylamino)ethyl]amino]-7-methoxy-9-oxo-9H-thioxanthen++ +-4-yl] methylformamide (SR271425, BCN326862, WIN71425). In preclinical testing against a variety of subcutaneously growing solid tumors, the following %T/C and Log10 tumor cell kill (LK) values were obtained: Panc-03 T/C = 0, 5/5 cures; Colon-38 (adv. stage) T/C = 0, 3/5 cures, 4.9 LK; Mam-16/C T/C = 0, 3.5 LK; Mam-17/0 T/C = 0, 2.8 LK; Colon-26 T/C = 0, 1/5 cures, 3.2 LK; Colon-51 T/C = 0, 2.7 LK; Panc-02 T/C = 0, 3.1 LK; B16 Melanoma T/C = 13%, 4.0 LK; Squamous Lung-LC12 (adv. stage) T/C = 14%, 4.9 LK; BG-1 human ovarian T/C = 16%, 1.3 LK; WSU-Brl human breast T/C = 25%, 0.8 LK. The agent was modestly active against doxorubicin (Adr)-resistant solid tumors: Mam-17/AdrT/C =23%, 0.8 LK; and Mam-16/C/Adr T/C = 25%, 1.0 LK, but retained substantial activity against a taxol-resistant tumor: Mam-16/C/taxol T/C = 3%, 2.4 LK. SR271425 was highly active against IV implanted leukemias, L1210 6.3 LK and AML1498 5.3 LK. The agent was equally active both by the IV and oral routes of administration, although requiring approximately 30% higher dose by the oral route. Based on its preclinical antitumor profile, it may be appropriate to evaluate SR271425 in clinical trials. PMID:10555119

  10. Neuraxial Analgesia In Neonates And Infants: Review of Clinical and Preclinical Strategies for the Development of Safety and Efficacy Data

    PubMed Central

    Walker, Suellen M.; Yaksh, Tony L.

    2015-01-01

    Neuraxial agents provide robust pain control, have the potential to improve outcomes, and are an important component of the perioperative care of children. Opioids or clonidine improve analgesia when added to perioperative epidural infusions; analgesia is significantly prolonged by addition of clonidine, ketamine, neostigmine or tramadol to single shot caudal injections of local anesthetic; and neonatal intrathecal anesthesia/analgesia is increasing in some centers. However, it is difficult to determine the relative risk-benefit of different techniques and drugs without detailed and sensitive data related to analgesia requirements, side-effects, and follow-up. Current data related to benefits and complications in neonates and infants are summarized, but variability in current neuraxial drug use reflects the relative lack of high quality evidence. Recent preclinical reports of adverse effects of general anesthetics on the developing brain have increased awareness of the potential benefit of neuraxial anesthesia/analgesia to avoid or reduce general anesthetic dose requirements. However, the developing spinal cord is also vulnerable to drug-related toxicity, and although there are well-established preclinical models and criteria for assessing spinal cord toxicity in adult animals, until recently there had been no systematic evaluation during early life. Therefore, the second half of this review presents preclinical data evaluating age-dependent changes in the pharmacodynamic response to different spinal analgesics, and recent studies evaluating spinal toxicity in specific developmental models. Finally, we advocate use of neuraxial agents with the widest demonstrable safety margin and suggest minimum standards for preclinical evaluation prior to adoption of new analgesics or preparations into routine clinical practice. PMID:22798528

  11. Novel technology to prepare oral formulations for preclinical safety studies.

    PubMed

    Niwa, Toshiyuki; Hashimoto, Naofumi

    2008-02-28

    A novel method to prepare oral formulations, normally suspended dosage form, for preclinical safety studies in animals has been developed using a rotation/revolution mixer. Small hard balls made of zirconia were added to the mixing process to evaluate effectiveness in making a high quality suspension. The driving with balls loaded in the cylindrical container (vessel) of the mixer was quite efficient in dispersing and milling the particles of the active pharmaceutical ingredient (API) in an aqueous medium. The API powder and a small amount of oral aqueous medium (vehicle) were successfully mixed by the spinning motion of the balls in the vessel as though the paste-like suspension was kneaded with a mortar and pestle. It was found that the milled suspension with the mean size of 10-20microm could be prepared, in addition finer milling of less than 10microm could be achieved by selecting the material of vessel. Optimum driving conditions including mixing time, size and quantity of balls, and the standard operational procedure was established using compounds varying in physicochemical properties. The particle size and quantitative analysis by HPLC showed that the resultant suspension was well-milled and highly homogeneous with the nearly intended concentration of API. The proposed method established by this experiment could be applied to the actual safety studies in the real preparation scale of oral suspension. PMID:17942253

  12. Liposomal-praziquantel: efficacy against Schistosoma mansoni in a preclinical assay.

    PubMed

    Frezza, Tarsila Ferraz; Gremio, Maria Palmira Daflon; Zanotti-Magalhes, Eliana Maria; Magalhes, Luiz Augusto; de Souza, Ana Luiza Ribeiro; Allegretti, Silmara Marques

    2013-10-01

    Currently, schistosomiasis mansoni is treated clinically with praziquantel (PZQ). Nevertheless, cases of tolerance and resistance to this drug have been reported, creating the need to develop new drugs or to improve existing drugs. Considering the small number of new drugs against Schistosoma mansoni, the design of nanotechnology-based drug delivery systems is an important strategy in combating this disease. The aim of this study was to evaluate the activity of PZQ containing liposome (lip.PZQ) on S. mansoni, BH strain. Mice were treated orally with different concentrations of PZQ and lip.PZQ 30 and 45 days following infection. The number of worms, recovered by perfusion of the hepatic portal system, and the number of eggs found in the intestine and liver were analysed. Parasite egg counts were also performed. The most active formulation for all parameters was 300mg/kg of lip.PZQ, since as it decreased the total number of worms by 68.8%, the number of eggs in the intestine by 79%, and the number of hepatic granulomas by 98.4% compared to untreated controls. In addition, this concentration decreased egg counts by 55.5%. The improved efficacy of the treatment with lip.PZQ, especially when administered 45 days following infection, compared with the positive-control group (untreated) and the groups that received free PZQ, can be explained by greater bioavailability in the host organism; the preferred target of lip.PZQ is the liver, and lip.PZQ is better absorbed by the tegument of S. mansoni, which has an affinity for phospholipids. PMID:23811113

  13. Decellularized myocardial matrix hydrogels: In basic research and preclinical studies.

    PubMed

    Wang, Raymond M; Christman, Karen L

    2016-01-15

    A variety of decellularized materials have been developed that have demonstrated potential for treating cardiovascular diseases and improving our understanding of cardiac development. Of these biomaterials, decellularized myocardial matrix hydrogels have shown great promise for creating cellular microenvironments representative of the native cardiac tissue and treating the heart after a myocardial infarction. Decellularized myocardial matrix hydrogels derived from porcine cardiac tissue form a nanofibrous hydrogel once thermally induced at physiological temperatures. Use of isolated cardiac extracellular matrix in 2D and 3D in vitro platforms has demonstrated the capability to provide tissue specific cues for cardiac cell growth and differentiation. Testing of the myocardial matrix hydrogel as a therapy after myocardial infarction in both small and large animal models has demonstrated improved left ventricular function, increased cardiac muscle, and cellular recruitment into the treated infarct. Based on these results, steps are currently being taken to translate these hydrogels into a clinically used injectable biomaterial therapy. In this review, we will focus on the basic science and preclinical studies that have accelerated the development of decellularized myocardial matrix hydrogels into an emerging novel therapy for treating the heart after a myocardial infarction. PMID:26056717

  14. Role of self-efficacy and anxiety among pre-clinically disabled older adults when using compensatory strategies to complete daily tasks

    PubMed Central

    Higgins, Torrance J.; Janelle, Christopher M.; Naugle, Kelly M.; Knaggs, Jeffrey; Hoover, Brian M.; Marsiske, Michael; Manini, Todd M.

    2012-01-01

    Classic developmental theory suggests that aging is associated with using compensatory strategies to prolong independence. While compensatory strategies are typically considered positive adaptations, they also signify an early phase in the disablement process commonly known as pre-clinical disability. To build a better understanding of psychological constructs related to these early signs of disability, we examined the contribution of self-efficacy and state anxiety on using compensatory strategies among pre-clinically disabled older adults. Compensatory strategies were observed during performance of daily activities in 257 pre-clinically disabled older adults (67.6 7.04), and self-efficacy and state anxiety were evaluated prior to performing each task. In univariate models, lower self-efficacy and higher anxiety were associated with more compensation (Spearman correlations: 0.15-0.48, p < 0.05). Multivariate logistic regression indicated that low self-efficacy [Odds Ratio (OR): 1.70; 95% Confidence Interval (CI): 1.40-2.08) and high anxiety (OR: 1.34; 95% CI: 1.10-1.63) were positively associated with using ? 6 compensatory strategies a level signifying substantial compensation. When considered jointly with self-efficacy, the association with anxiety was reversed higher anxiety demonstrated a lower likelihood of using compensation (OR: 0.70-0.73; 95% CI: 0.50-0.99). The addition of self-efficacy might remove the self-defeating cognitions characterizing anxiety allowing the remaining arousal component to appear beneficial. In conclusion, lower self-efficacy and higher anxiety are associated with using compensation to complete daily tasks among pre-clinically disabled older adults. Such psychological constructs may contribute to the use of compensatory strategies and represent future intervention targets to help reduce early signs of disability. PMID:22770713

  15. Preclinical experimental stress studies: protocols, assessment and comparison.

    PubMed

    Bali, Anjana; Jaggi, Amteshwar Singh

    2015-01-01

    Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Preclinical models are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these models are also important for the development of novel pharmacological agents for stress management. The well described preclinical stress models include immobilization, restraint, electric foot shock and social isolation stress. Stress assessment in animals is done at the behavioral level using open field, social interaction, hole board test; at the biochemical level by measuring plasma corticosterone and ACTH; at the physiological level by measuring food intake, body weight, adrenal gland weight and gastric ulceration. Furthermore the comparison between different stressors including electric foot shock, immobilization and cold stressor is described in terms of intensity, hormonal release, protein changes in brain, adaptation and sleep pattern. This present review describes these preclinical stress protocols, and stress assessment at different levels. PMID:25446911

  16. Antithrombotic drug candidate ALX-0081 shows superior preclinical efficacy and safety compared with currently marketed antiplatelet drugs.

    PubMed

    Ulrichts, Hans; Silence, Karen; Schoolmeester, Anne; de Jaegere, Peter; Rossenu, Stefaan; Roodt, Jan; Priem, Sofie; Lauwereys, Marc; Casteels, Peter; Van Bockstaele, Femke; Verschueren, Katrien; Stanssens, Patrick; Baumeister, Judith; Holz, Josefin-Beate

    2011-07-21

    Neutralizing the interaction of the platelet receptor gpIb with VWF is an attractive strategy to treat and prevent thrombotic complications. ALX-0081 is a bivalent Nanobody which specifically targets the gpIb-binding site of VWF and interacts avidly with VWF. Nanobodies are therapeutic proteins derived from naturally occurring heavy-chain-only Abs and combine a small molecular size with a high inherent stability. ALX-0081 exerts potent activity in vitro and in vivo. Perfusion experiments with blood from patients with acute coronary syndrome on standard antithrombotics demonstrated complete inhibition of platelet adhesion after addition of ALX-0081, while in the absence of ALX-0081 residual adhesion was observed. In a baboon efficacy and safety model measuring acute thrombosis and surgical bleeding, ALX-0081 showed a superior therapeutic window compared with marketed antithrombotics. Pharmacokinetic and biodistribution experiments demonstrated target-mediated clearance of ALX-0081, which leads to a self-regulating disposition behavior. In conclusion, these preclinical data demonstrate that ALX-0081 combines a high efficacy with an improved safety profile compared with currently marketed antithrombotics. ALX-0081 has entered clinical development. PMID:21576702

  17. Single agent efficacy of the VEGFR kinase inhibitor axitinib in preclinical models of glioblastoma

    PubMed Central

    Lu, Lei; Saha, Dipongkor; Martuza, Robert L.; Rabkin, Samuel D.; Wakimoto, Hiroaki

    2016-01-01

    Anti-angiogenic therapy is a promising therapeutic strategy for the highly vascular and malignant brain tumor, glioblastoma (GBM), although current clinical trials have failed to demonstrate an extension in overall survival. The small molecule tyrosine kinase inhibitor axitinib that targets vascular endothelial growth factor receptor, potently inhibits angiogenesis and has single-agent clinical activity in non-small cell lung, thyroid, and advanced renal cell cancer. Here we show that axitinib exerts direct cytotoxic activity against a number of patient-derived GBM stem cell (GSCs) and an endothelial cell line, and inhibits endothelial tube formation in vitro. Axitinib treatment of mice bearing hypervascular intracranial tumors generated from human U87 glioma cells, MGG4 GSCs and mouse 005 GSCs significantly extended survival that was associated with decreases in tumor-associated vascularity. We thus show for the first time the anti-angiogenic effect and survival prolongation provided by systemic single agent treatment with axitinib in preclinical orthotopic GBM models including clinically relevant GSC models. These results support further investigation of axitinib as an anti-angiogenic agent for GBM. PMID:25213669

  18. Rodent Preclinical Models for Developing Novel Antiarthritic Molecules: Comparative Biology and Preferred Methods for Evaluating Efficacy

    PubMed Central

    Bolon, Brad; Stolina, Marina; King, Caroline; Middleton, Scot; Gasser, Jill; Zack, Debra; Feige, Ulrich

    2011-01-01

    Rodent models of immune-mediated arthritis (RMIA) are the conventional approach to evaluating mechanisms of inflammatory joint disease and the comparative efficacy of antiarthritic agents. Rat adjuvant-induced (AIA), collagen-induced (CIA), and streptococcal cell wall-induced (SCW) arthritides are preferred models of the joint pathology that occurs in human rheumatoid arthritis (RA). Lesions of AIA are most severe and consistent; structural and immunological changes of CIA best resemble RA. Lesion extent and severity in RMIA depends on experimental methodology (inciting agent, adjuvant, etc.) and individual physiologic parameters (age, genetics, hormonal status, etc.). The effectiveness of antiarthritic molecules varies with the agent, therapeutic regimen, and choice of RMIA. All RMIA are driven by overactivity of proinflammatory pathways, but the dominant molecules differ among the models. Hence, as with the human clinical experience, the efficacy of various antiarthritic molecules differs among RMIA, especially when the agent is a specific cytokine inhibitor. PMID:21253435

  19. Preclinical examination of clofarabine in pediatric ependymoma: intratumoral concentrations insufficient to warrant further study.

    PubMed

    Patel, Yogesh T; Jacus, Megan O; Boulos, Nidal; Dapper, Jason D; Davis, Abigail D; Vuppala, Pradeep K; Freeman, Burgess B; Mohankumar, Kumarasamypet M; Throm, Stacy L; Gilbertson, Richard J; Stewart, Clinton F

    2015-05-01

    Clofarabine, a deoxyadenosine analog, was an active anticancer drug in our in vitro high-throughput screening against mouse ependymoma neurospheres. To characterize the clofarabine disposition in mice for further preclinical efficacy studies, we evaluated the plasma and central nervous system disposition in a mouse model of ependymoma. A plasma pharmacokinetic study of clofarabine (45mg/kg, IP) was performed in CD1 nude mice bearing ependymoma to obtain initial plasma pharmacokinetic parameters. These estimates were used to derive D-optimal plasma sampling time points for cerebral microdialysis studies. A simulation of clofarabine pharmacokinetics in mice and pediatric patients suggested that a dosage of 30mg/kg IP in mice would give exposures comparable to that in children at a dosage of 148mg/m(2). Cerebral microdialysis was performed to study the tumor extracellular fluid (ECF) disposition of clofarabine (30mg/kg, IP) in the ependymoma cortical allografts. Plasma and tumor ECF concentration-time data were analyzed using a nonlinear mixed effects modeling approach. The median unbound fraction of clofarabine in mouse plasma was 0.79. The unbound tumor to plasma partition coefficient (K pt,uu: ratio of tumor to plasma AUCu,0-inf) of clofarabine was 0.120.05. The model-predicted mean tumor ECF clofarabine concentrations were below the in vitro 1-h IC50 (407ng/mL) for ependymoma neurospheres. Thus, our results show the clofarabine exposure reached in the tumor ECF was below that associated with an antitumor effect in our in vitro washout study. Therefore, clofarabine was de-prioritized as an agent to treat ependymoma, and further preclinical studies were not pursued. PMID:25724157

  20. Preclinical safety studies on autologous cultured human skin fibroblast transplantation.

    PubMed

    Zeng, Wei; Zhang, Shuying; Liu, Dai; Chai, Mi; Wang, Jiaqi; Zhao, Yuming

    2014-01-01

    Recently, FDA approved the clinical use of autologous fibroblasts (LAVIV) for the improvement of nasolabial fold wrinkles in adults. The use of autologous fibroblasts for the augmentation of dermal and subcutaneous defects represents a potentially exciting natural alternative to the use of other filler materials for its long-term corrective ability and absence of allergic adverse effects proved by clinical application. However, compared to the clinical evidence, preclinical studies are far from enough. In this study, human skin-derived fibroblasts were cultured and expanded for both in vitro and in vivo observations. In vitro, the subcultured fibroblasts were divided into two groups. One set of cells underwent cell cycle and karyotype analysis at passages 5 and 10. The second group of cells was cocultured in medium with different concentrations of human skin extract D for the measurement of collagen concentration and cell count. In vivo, the subcultured fibroblasts were injected into nude mice subcutaneously. Biopsies were taken for morphology observation and specific collagen staining at 1, 2, and 3 months after injection. The results in vitro showed no significant differences in cell cycle distribution between passages 5 and 10. Cell proliferation and secretion were inhibited as the concentration of extract D increased. In vivo, the fibroblasts were remarkably denser on the experimental side with no dysplastic cells. Mitotic cells were easily observed at the end of the first month but were rare at the end of the third month. Type III collagen was detected at the end of the first month, while collagen type I was positive at the end of the second month. The content of both collagens increased as time passed. The above results indicated that the use of the autologous fibroblasts was safe, providing a basic support for clinical use of fibroblasts. PMID:23211390

  1. Sequential whole bladder photodynamic therapy treatments: A preclinical study.

    PubMed

    Nseyo, U O; Kim, H; Debord, J; Tate, K; Dehaven, J

    1997-01-01

    We postulated that sequential whole bladder photodynamic therapy (WBPDT) treatments with a low WBPDT dose would result in improved safety profile and good local tumor control. However, the drawback with such a proposal is the potential cumulative effect of sequential WBPDT treatments on bladder function. We designed this preclinical study to determine the safety of sequential WBPDT treatments. Six female dogs underwent a single WBPDT treatment comprising 1.5 mg/kg of Photofrin and 15 J/cm(2) of light. Four dogs received a second treatment; and three dogs received three treatments. Pre- and post-WBPDT evaluations included cystoscopy and saline cystometry at baseline, 1 week, and 12 weeks. Gross and histopathologic analysis of cystectomy specimens occurred at 1 and 12 weeks. A single photodynamic therapy (PDT) treatment induced average bladder capacity losses of 11% (0-33) and 0% at post-WBPDT weeks 1 and 12, respectively. A second sequential WBPDT treatment caused average bladder capacity losses of 36% (0-57%) and 17% (2-24%) at weeks 1 and 12, respectively. Three sequential WBPDT treatments induced average bladder capacity losses of 22% (0-42) and 0% at weeks 1 and 12, respectively. Full recovery in bladder capacity occurred in all cases except after the second sequential treatment, which induced a persistent bladder capacity loss of 17% at 12 weeks. Histopathologic analysis of cystectomy specimens revealed a focal discernible injury to the superficial muscle in only one of the dogs that received three treatments. We conclude that sequential WBPDT treatments using low dose PDT Photofrin (1.5 mg/kg and light ?15 J/cm(2)) is safe, and we recommend using this low WBPDT dose in clinical investigation. PMID:21227049

  2. Selective small molecule angiotensin II type 2 receptor antagonists for neuropathic pain: preclinical and clinical studies.

    PubMed

    Smith, Maree T; Anand, Praveen; Rice, Andrew S C

    2016-02-01

    Neuropathic pain affects up to 10% of the general population, but drug treatments recommended for the treatment of neuropathic pain are associated with modest efficacy and/or produce dose-limiting side effects. Hence, neuropathic pain is an unmet medical need. In the past 2 decades, research on the pathobiology of neuropathic pain has revealed many novel pain targets for use in analgesic drug discovery programs. However, these efforts have been largely unsuccessful as molecules that showed promising pain relief in rodent models of neuropathic pain generally failed to produce analgesia in early phase clinical trials in patients with neuropathic pain. One notable exception is the angiotensin II type 2 (AT2) receptor that has clinical validity on the basis of a successful double-blind, randomized, placebo-controlled, clinical trial of EMA401, a highly selective, orally active, peripherally restricted AT2 receptor antagonist in patients with postherpetic neuralgia. In this study, we review research to date on target validation, efficacy, and mode of action of small molecule AT2 receptor antagonists in rodent models of peripheral neuropathic pain and in cultured human sensory neurons, the preclinical pharmacokinetics of these compounds, and the outcome of the above clinical trial. PMID:26785154

  3. Preclinical Evidence for the Efficacy of Ischemic Postconditioning against Renal Ischemia-Reperfusion Injury, a Systematic Review and Meta-Analysis

    PubMed Central

    Jonker, Simone J.; Menting, Theo P.; Warlé, Michiel C.; Ritskes-Hoitinga, Merel; Wever, Kimberley E.

    2016-01-01

    Background Renal ischemia-reperfusion injury (IRI) is a major cause of kidney damage after e.g. renal surgery and transplantation. Ischemic postconditioning (IPoC) is a promising treatment strategy for renal IRI, but early clinical trials have not yet replicated the promising results found in animal studies. Method We present a systematic review, quality assessment and meta-analysis of the preclinical evidence for renal IPoC, and identify factors which modify its efficacy. Results We identified 39 publications studying >250 control animals undergoing renal IRI only and >290 animals undergoing renal IRI and IPoC. Healthy, male rats undergoing warm ischemia were used in the vast majority of studies. Four studies applied remote IPoC, all others used local IPoC. Meta-analysis showed that both local and remote IPoC ameliorated renal damage after IRI for the outcome measures serum creatinine, blood urea nitrogen and renal histology. Subgroup analysis indicated that IPoC efficacy increased with the duration of index ischemia. Measures to reduce bias were insufficiently reported. Conclusion High efficacy of IPoC is observed in animal models, but factors pertaining to the internal and external validity of these studies may hamper the translation of IPoC to the clinical setting. The external validity of future animal studies should be increased by including females, comorbid animals, and transplantation models, in order to better inform clinical trial design. The severity of renal damage should be taken into account in the design and analysis of future clinical trials. PMID:26963819

  4. Mouse Model for the Preclinical Study of Metastatic Disease

    Cancer.gov

    The successful development of new cancer therapeutics requires reliable preclinical data that are obtained from mouse models for cancer. Human tumor xenografts, which require transplantation of human tumor cells into an immune compromised mouse, represent the current standard mouse model for cancer. Since the immune system plays an important role in tumor growth, progression and metastasis, the current standard mouse model is not ideal for accurate prediction of therapeutic effectiveness in patients.

  5. Dabrafenib; preclinical characterization, increased efficacy when combined with trametinib, while BRAF/MEK tool combination reduced skin lesions.

    PubMed

    King, Alastair J; Arnone, Marc R; Bleam, Maureen R; Moss, Katherine G; Yang, Jingsong; Fedorowicz, Kelly E; Smitheman, Kimberly N; Erhardt, Joseph A; Hughes-Earle, Angela; Kane-Carson, Laurie S; Sinnamon, Robert H; Qi, Hongwei; Rheault, Tara R; Uehling, David E; Laquerre, Sylvie G

    2013-01-01

    Mitogen-Activated Protein Kinase (MAPK) pathway activation has been implicated in many types of human cancer. BRAF mutations that constitutively activate MAPK signalling and bypass the need for upstream stimuli occur with high prevalence in melanoma, colorectal carcinoma, ovarian cancer, papillary thyroid carcinoma, and cholangiocarcinoma. In this report we characterize the novel, potent, and selective BRAF inhibitor, dabrafenib (GSK2118436). Cellular inhibition of BRAF(V600E) kinase activity by dabrafenib resulted in decreased MEK and ERK phosphorylation and inhibition of cell proliferation through an initial G1 cell cycle arrest, followed by cell death. In a BRAF(V600E)-containing xenograft model of human melanoma, orally administered dabrafenib inhibited ERK activation, downregulated Ki67, and upregulated p27, leading to tumor growth inhibition. However, as reported for other BRAF inhibitors, dabrafenib also induced MAPK pathway activation in wild-type BRAF cells through CRAF (RAF1) signalling, potentially explaining the squamous cell carcinomas and keratoacanthomas arising in patients treated with BRAF inhibitors. In addressing this issue, we showed that concomitant administration of BRAF and MEK inhibitors abrogated paradoxical BRAF inhibitor-induced MAPK signalling in cells, reduced the occurrence of skin lesions in rats, and enhanced the inhibition of human tumor xenograft growth in mouse models. Taken together, our findings offer preclinical proof of concept for dabrafenib as a specific and highly efficacious BRAF inhibitor and provide evidence for its potential clinical benefits when used in combination with a MEK inhibitor. PMID:23844038

  6. Dabrafenib; Preclinical Characterization, Increased Efficacy when Combined with Trametinib, while BRAF/MEK Tool Combination Reduced Skin Lesions

    PubMed Central

    King, Alastair J.; Arnone, Marc R.; Bleam, Maureen R.; Moss, Katherine G.; Yang, Jingsong; Fedorowicz, Kelly E.; Smitheman, Kimberly N.; Erhardt, Joseph A.; Hughes-Earle, Angela; Kane-Carson, Laurie S.; Sinnamon, Robert H.; Qi, Hongwei; Rheault, Tara R.; Uehling, David E.; Laquerre, Sylvie G.

    2013-01-01

    Mitogen-Activated Protein Kinase (MAPK) pathway activation has been implicated in many types of human cancer. BRAF mutations that constitutively activate MAPK signalling and bypass the need for upstream stimuli occur with high prevalence in melanoma, colorectal carcinoma, ovarian cancer, papillary thyroid carcinoma, and cholangiocarcinoma. In this report we characterize the novel, potent, and selective BRAF inhibitor, dabrafenib (GSK2118436). Cellular inhibition of BRAFV600E kinase activity by dabrafenib resulted in decreased MEK and ERK phosphorylation and inhibition of cell proliferation through an initial G1 cell cycle arrest, followed by cell death. In a BRAFV600E-containing xenograft model of human melanoma, orally administered dabrafenib inhibited ERK activation, downregulated Ki67, and upregulated p27, leading to tumor growth inhibition. However, as reported for other BRAF inhibitors, dabrafenib also induced MAPK pathway activation in wild-type BRAF cells through CRAF (RAF1) signalling, potentially explaining the squamous cell carcinomas and keratoacanthomas arising in patients treated with BRAF inhibitors. In addressing this issue, we showed that concomitant administration of BRAF and MEK inhibitors abrogated paradoxical BRAF inhibitor-induced MAPK signalling in cells, reduced the occurrence of skin lesions in rats, and enhanced the inhibition of human tumor xenograft growth in mouse models. Taken together, our findings offer preclinical proof of concept for dabrafenib as a specific and highly efficacious BRAF inhibitor and provide evidence for its potential clinical benefits when used in combination with a MEK inhibitor. PMID:23844038

  7. Preclinical efficacy of the synthetic retinoid ST1926 for treating adult T-cell leukemia/lymphoma.

    PubMed

    El Hajj, Hiba; Khalil, Bariaa; Ghandour, Botheina; Nasr, Rihab; Shahine, Sharif; Ghantous, Akram; Abdel-Samad, Rana; Sinjab, Ansam; Hasegawa, Hideki; Jabbour, Mark; Hall, William W; Zaatari, Ghazi; Dbaibo, Ghassan; Pisano, Claudio; Bazarbachi, Ali; Darwiche, Nadine

    2014-09-25

    Adult T-cell leukemia/lymphoma (ATL) is an aggressive neoplasm caused by human T-cell leukemia virus type 1 (HTLV-1). The HTLV-1 oncoprotein Tax plays an important role in ATL pathogenesis. ATL carries a poor prognosis due to chemotherapy resistance, stressing the need for alternative therapies. Here, we investigate the preclinical efficacy of the synthetic retinoid ST1926 in ATL and peripheral T-cell lymphomas. Clinically achievable concentrations of ST1926 induced a dramatic inhibition of cell proliferation in malignant T-cell lines and primary ATL cells with minimal effect on resting or activated normal lymphocytes. ST1926 induced apoptosis, DNA damage, and upregulation of p53 proteins in malignant T cells, whereas it caused an early downregulation of Tax proteins in HTLV-1-positive cells. In murine ATL, oral treatment with ST1926 prolonged survival and reduced leukemia cell infiltration, white blood cell counts, and spleen mass. In spleens of ST1926-treated animals, p53 and p21 proteins were upregulated, poly (ADP-ribose) polymerase was cleaved, and Tax transcripts were reduced. These results highlight the promising use of ST1926 as a targeted therapy for ATL. PMID:25035162

  8. Preclinical studies identify novel targeted pharmacological strategies for treatment of human malignant pleural mesothelioma

    PubMed Central

    Favoni, Roberto E; Daga, Antonio; Malatesta, Paolo; Florio, Tullio

    2012-01-01

    The incidence of human malignant pleural mesothelioma (hMPM) is still increasing worldwide. hMPM prognosis is poor even if the median survival time has been slightly improved after the introduction of the up-to-date chemotherapy. Nevertheless, large phase II/III trials support the combination of platinum derivatives and pemetrexed or raltitrexed, as preferred first-line schedule. Better understanding of the molecular machinery of hMPM will lead to the design and synthesis of novel compounds targeted against pathways identified as crucial for hMPM cell proliferation and spreading. Among them, several receptors tyrosine kinase show altered activity in subsets of hMPM. This observation suggests that these kinases might represent novel therapeutic targets in this chemotherapy-resistant disease. Over these foundations, several promising studies are ongoing at preclinical level and novel molecules are currently under evaluation as well. Yet, established tumour cell lines, used for decades to investigate the efficacy of anticancer agents, although still the main source of drug efficacy studies, after long-term cultures tend to biologically diverge from the original tumour, limiting the predictive potential of in vivo efficacy. Cancer stem cells (CSCs), a subpopulation of malignant cells capable of self-renewal and multilineage differentiation, are believed to play an essential role in cancer initiation, growth, metastasization and relapse, being responsible of chemo- and radiotherapy refractoriness. According to the current carcinogenesis theory, CSCs represent the tumour-initiating cell (TIC) fraction, the only clonogenic subpopulation able to originate a tumour mass. Consequently, the recently described isolation of TICs from hMPM, the proposed main pharmacological target for novel antitumoural drugs, may contribute to better dissect the biology and multidrug resistance pathways controlling hMPM growth. PMID:22289125

  9. Preclinical studies identify novel targeted pharmacological strategies for treatment of human malignant pleural mesothelioma.

    PubMed

    Favoni, Roberto E; Daga, Antonio; Malatesta, Paolo; Florio, Tullio

    2012-05-01

    The incidence of human malignant pleural mesothelioma (hMPM) is still increasing worldwide. hMPM prognosis is poor even if the median survival time has been slightly improved after the introduction of the up-to-date chemotherapy. Nevertheless, large phase II/III trials support the combination of platinum derivatives and pemetrexed or raltitrexed, as preferred first-line schedule. Better understanding of the molecular machinery of hMPM will lead to the design and synthesis of novel compounds targeted against pathways identified as crucial for hMPM cell proliferation and spreading. Among them, several receptors tyrosine kinase show altered activity in subsets of hMPM. This observation suggests that these kinases might represent novel therapeutic targets in this chemotherapy-resistant disease. Over these foundations, several promising studies are ongoing at preclinical level and novel molecules are currently under evaluation as well. Yet, established tumour cell lines, used for decades to investigate the efficacy of anticancer agents, although still the main source of drug efficacy studies, after long-term cultures tend to biologically diverge from the original tumour, limiting the predictive potential of in vivo efficacy. Cancer stem cells (CSCs), a subpopulation of malignant cells capable of self-renewal and multilineage differentiation, are believed to play an essential role in cancer initiation, growth, metastasization and relapse, being responsible of chemo- and radiotherapy refractoriness. According to the current carcinogenesis theory, CSCs represent the tumour-initiating cell (TIC) fraction, the only clonogenic subpopulation able to originate a tumour mass. Consequently, the recently described isolation of TICs from hMPM, the proposed main pharmacological target for novel antitumoural drugs, may contribute to better dissect the biology and multidrug resistance pathways controlling hMPM growth. PMID:22289125

  10. [Human recombinant erythropoietin-alpha increases the efficacy of irradiation in preclinical model].

    PubMed

    Lvey, Jzsef; Kenessey, Istvn; Rs, Erzsbet; Dobos, Judit; Vg, Agnes; Ksler, Mikls; Futosi, Krisztina; Dme, Balzs; Tmr, Jzsef; Tvri, Jzsef

    2007-01-01

    According to recent data erythropoietin receptor (EPOR) is expressed not only by bone marrow erythroid progenitors but by endothelial- and cancer cells and it was suggested that erythropoietin (EPO) may affect their functions as well. We have analyzed the effects of recombinant human erythropoietin-alpha (rHuEPOalpha) on radiation sensitivity of EPOR+ human epidermoid carcinoma (A431) xenograft model. In vivo rHuEPOalpha treatment was started after tumor cell inoculation into SCID mice. 5 Gy irradiation was performed on day 14, the effect of which was measured on day 22. Hemoglobin level, tumor-associated microvessels and HIF-1alpha expression of the xenograft were monitored during the experiment. rHuEPOalpha administration prevented the development of tumor-induced anemia of SCID mice and reduced the level of HIF-1alpha expression of the xenograft tumor without affecting tumor growth. We have found that rHuEPOalpha treatment significantly increased the efficacy of antitumor effect of irradiation which was partly mediated by complex effects on tumor-associated microvessels. In vitro rHuEPOalpha did not affect proliferation of A431 cells but enhanced the antiproliferative and proapoptotic effects of irradiation. We concluded that rHuEPOalpha administration positively modulated the antitumoral effects of irradiation at least by two pathways, decreasing systemic hypoxia resulting in decreased tumoral HIF-1alpha expression and enhancing direct effects on tumor-associated microvessels. PMID:17417676

  11. Pharmacokinetics, Trypanosoma brucei gambiense Efficacy, and Time of Drug Action of DB829, a Preclinical Candidate for Treatment of Second-Stage Human African Trypanosomiasis

    PubMed Central

    Wenzler, Tanja; Yang, Sihyung; Braissant, Olivier; Boykin, David W.; Brun, Reto

    2013-01-01

    Human African trypanosomiasis (HAT, also called sleeping sickness), a neglected tropical disease endemic to sub-Saharan Africa, is caused by the parasites Trypanosoma brucei gambiense and T. brucei rhodesiense. Current drugs against this disease have significant limitations, including toxicity, increasing resistance, and/or a complicated parenteral treatment regimen. DB829 is a novel aza-diamidine that demonstrated excellent efficacy in mice infected with T. b. rhodesiense or T. b. brucei parasites. The current study examined the pharmacokinetics, in vitro and in vivo activity against T. b. gambiense, and time of drug action of DB829 in comparison to pentamidine. DB829 showed outstanding in vivo efficacy in mice infected with parasites of T. b. gambiense strains, despite having higher in vitro 50% inhibitory concentrations (IC50s) than against T. b. rhodesiense strain STIB900. A single dose of DB829 administered intraperitoneally (5 mg/kg of body weight) cured all mice infected with different T. b. gambiense strains. No cross-resistance was observed between DB829 and pentamidine in T. b. gambiense strains isolated from melarsoprol-refractory patients. Compared to pentamidine, DB829 showed a greater systemic exposure when administered intraperitoneally, partially contributing to its improved efficacy. Isothermal microcalorimetry and in vivo time-to-kill studies revealed that DB829 is a slower-acting trypanocidal compound than pentamidine. A single dose of DB829 (20 mg/kg) administered intraperitoneally clears parasites from mouse blood within 2 to 5 days. In summary, DB829 is a promising preclinical candidate for the treatment of first- and second-stage HAT caused by both Trypanosoma brucei subspecies. PMID:23959303

  12. Review of Preclinical Studies on Treatment of Mucositis and Associated Pain

    PubMed Central

    Viet, C.T.; Corby, P.M.; Akinwande, A.; Schmidt, B.L.

    2014-01-01

    Oral mucositis is a significant problem in cancer patients treated with radiation or chemotherapy, often hindering definitive cancer treatment. For patients with oral mucositis, pain is the most distressing symptom, leading to loss of orofacial function and poor quality of life. While oral mucositis has been well-described, its pathophysiology is poorly understood. Oral health professionals treating patients with mucositis have almost no effective therapies to treat or prevent oral mucositis. The purpose of this review is to (1) describe the current preclinical models of oral mucositis and their contribution to the understanding of mucositis pathophysiology, (2) explore preclinical studies on therapies targeting mucositis and discuss the clinical trials that have resulted from these preclinical studies, and (3) describe the proposed pathophysiology of oral mucositis pain and preclinical modeling of oral mucositis pain. PMID:24943201

  13. Fluorescence detection of tumors: studies on the early diagnosis of microscopic lesions in preclinical and clinical studies

    NASA Astrophysics Data System (ADS)

    Mang, Thomas S.; McGinnis, Carolyn; Crean, David H.; Khan, S.; Liebow, Charles

    1991-06-01

    The growth of microscopic tumor lesions at or beyond treatment field lesions poses major problems in the diagnosis and curative treatment of numerous cancers. Early detection techniques which clearly define the extent of condemned or field spread of disease may improve the primary treatment of the disease. In vivo fluorescence photometry is a non-imaging technique which digitally displays relative fluorescence values in volts. The sensitivity of the instrument has allowed the detection of micrometastases in both pre-clinical and clinical studies using drug doses that are 80-90 lower than those used therapeutically. This technique is now being applied in preliminary experiments to the hamster cheek pouch models to (1) discern varying grades of dysplasia; (2) levels of uptake of the drug in normal growing and quiescent tumors. Results will be shown in two models in which this technique has shown to be efficacious preclinically in the Pollard rat adenocarcinoma model in which micrometastases in the lymph node have been detected, and preliminary studies involving the hamster cheek pouch model in which the pouch is painted with 9, 10 dimethyl-1, 2-benzanthracene (DMBA) for initiation and promotion of tumors. Clinically results will be shown in which fluorescence detection, confirmed by biopsy and histopathological examination, was capable of detecting the existence of micrometastatic involvement of less than 100 cells.

  14. MRI biomarkers for evaluation of treatment efficacy in preclinical diabetic retinopathy

    PubMed Central

    Berkowitz, Bruce A; Bissig, David; Dutczak, Oliver; Corbett, Shannon; North, Rob; Roberts, Robin

    2014-01-01

    Introduction: One sober consequence of the current epidemic of diabetes mellitus is that an increasing number of people world-wide will partially or completely lose their sight to diabetic retinopathy. Clinically, the sight-threatening complications of diabetes are diagnosed and treated based on visible retinal lesions (e.g., dot-blot hemorrhages or retinal neovascularization). However, such anatomical microvascular lesions are slow to respond with treatment. Thus, there remains an urgent need for imaging biomarkers that are abnormal before retinal lesions are visibly apparent and are responsive to treatment. Areas covered: Here, the development of new MRI methods, such as manganese-enhanced MRI, for evaluating early diabetes-evoked retinal pathophysiology, and its usefulness in guiding new treatments for diabetic retinopathy are reviewed. Expert opinion: In diabetic retinopathy, not all important diagnostic and prognostic needs are well served by optical methods. In the absence of gross anatomy changes, critical times when drug intervention is most likely to be successful at reducing vision loss are missed by most light-based methods and thus provide little help in guiding diagnosis and treatment. For example, before clinical symptoms, is there an optimal time to intervene with drug therapy? Is a drug reaching its target? How does one assess optimal drug dose, schedule, and routes? How well do current experimental models mimic the clinical condition? As discussed herein, MRI is as an analytical tool for addressing these unmet needs. Future clinical applications of MRI can be envisioned such as in clinical trials to assess drug treatment efficacy, or as an adjunct approach to refine or clarify a difficult clinical case. New MRI-generated hypotheses about the pathogenesis of diabetic retinopathy and its treatment are discussed. In the coming years, a substantial growth in the development and application of MRI is expected to address relevant question in both the basic sciences and in the clinic. PMID:23786440

  15. Preclinical Efficacy of Clumping Factor A in Prevention of Staphylococcus aureus Infection

    PubMed Central

    Li, Xue; Wang, Xiaogang; Thompson, Christopher D.; Park, Saeyoung; Park, Wan Beom

    2016-01-01

    ABSTRACT Treatment of Staphylococcus aureus infections has become increasingly difficult because of the emergence of multidrug-resistant isolates. Development of a vaccine to prevent staphylococcal infections remains a priority. To determine whether clumping factor A (ClfA) is a good target protein for inclusion in a multivalent vaccine, we evaluated its efficacy in a variety of relevant staphylococcal infection models, challenging with different S. aureus strains. ClfA adsorbed to Alhydrogel and mixed with Sigma Adjuvant System was more immunogenic and stimulated a more robust Th17 response than ClfA administered with alum alone. ClfA immunization induced the production of functional antibodies in rabbits and mice that blocked S. aureus binding to fibrinogen and were opsonic for S. aureus strains that produced little or no capsular polysaccharide. Mice immunized with ClfA showed a modest reduction in the bacterial burden recovered from subcutaneous abscesses provoked by S. aureus USA300 strain LAC. In addition, the ClfA vaccine reduced lethality in a sepsis model following challenge with strain Newman, but not ST80. Vaccination with ClfA did not protect against surgical wound infection, renal abscess formation, or bacteremia. Passive immunization with antibodies to ClfA did not protect against staphylococcal bacteremia in mice or catheter-induced endocarditis in rats. Some enhancement of bacteremia was observed by ClfA immunization or passive administration of ClfA antibodies when mice were challenged by the intraperitoneal route. Although rodent models of staphylococcal infection have their limitations, our data do not support the inclusion of ClfA in an S. aureus multivalent vaccine. PMID:26838725

  16. Cognitive and emotional behavioural changes associated with methylphenidate treatment: a review of preclinical studies.

    PubMed

    Britton, Gabrielle B

    2012-02-01

    There is evidence from animal studies that repeated exposure to methylphenidate (MPH), a widely used psychostimulant for the treatment of attention deficit hyperactivity disorder (ADHD), produces behavioural, structural and neurochemical changes that persist long after drug administration has ended. However, the translational utility of much of this work is compromised by the use of drug doses and routes of administration that produce plasma and brain MPH levels that fall outside the clinical range, i.e. experimental parameters more relevant to drug abuse than ADHD. We used PubMed to identify pre-clinical studies that employed repeated MPH administration at low doses in young rodents and examined long-term effects on cognition, emotion, and brain structure and function. A review of this work suggests that repeated MPH treatment during early development can modify a number of cognitive, behavioural and brain processes, but these are reduced when low therapeutic doses are employed. Moreover, MPH sites of action extend beyond those implicated in ADHD. Studies that combined neurobiological and behavioural approaches provide important insights into the mechanisms underlying MPH-produced effects on cognitive and behavioural processes, which may be relevant to MPH therapeutic efficacy. There is an emerging consensus that pharmacological treatment of childhood psychiatric disorders produces persistent neuroadaptations, highlighting the need for studies that assess long-term effects of early developmental pharmacotherapy. In this regard, studies that mimic clinical therapy with rodents are useful experimental approaches for defining the behavioural and neural plasticity associated with stimulant therapy in paediatric populations. PMID:21439107

  17. Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study

    PubMed Central

    Eissa, Maha M.; El-Moslemany, Riham M.; Ramadan, Alyaa A.; Amer, Eglal I.; El-Azzouni, Mervat Z.; El-Khordagui, Labiba K.

    2015-01-01

    Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting via the oral route. From a clinical point of view, data suggest MFS-LNCs as a potential single dose oral nanomedicine for enhanced therapy of schistosomiasis mansoni and possibly other diseases. PMID:26574746

  18. The effect of learning styles and study behavior on success of preclinical students in pharmacology

    PubMed Central

    Asci, Halil; Kulac, Esin; Sezik, Mekin; Cankara, F. Nihan; Cicek, Ekrem

    2016-01-01

    Objectives: To evaluate the effect of learning styles and study behaviors on preclinical medical students’ pharmacology exam scores in a non-Western setting. Materials and Methods: Grasha–Reichmann Student Learning Study Scale and a modified Study Behavior Inventory were used to assess learning styles and study behaviors of preclinical medical students (n = 87). Logistic regression models were used to evaluate the independent effect of gender, age, learning style, and study behavior on pharmacology success. Results: Collaborative (40%) and competitive (27%) dominant learning styles were frequent in the cohort. The most common study behavior subcategories were study reading (40%) and general study habits (38%). Adequate listening and note-taking skills were associated with pharmacology success, whereas students with adequate writing skills had lower exam scores. These effects were independent of gender. Conclusions: Preclinical medical students’ study behaviors are independent predictive factors for short-term pharmacology success. PMID:26997716

  19. Potent efficacy of metronomic topotecan and pazopanib combination therapy in preclinical models of primary or late stage metastatic triple-negative breast cancer.

    PubMed

    Di Desidero, Teresa; Xu, Ping; Man, Shan; Bocci, Guido; Kerbel, Robert S

    2015-12-15

    Metronomic chemotherapy has shown promising activity in numerous preclinical studies and also some phase II clinical studies involving various tumor types, and is currently undergoing phase III trial evaluation. Triple-negative breast cancer (TNBC) is an aggressive histological subtype with limited treatment options and very poor prognosis following progression after standard chemotherapeutic regimens. Herein, we evaluated the potential therapeutic impact and molecular mechanisms of topotecan administered in a continuous low-dose metronomic (LDM) manner, alone or in concurrent combination with pazopanib, an antiangiogenic tyrosine kinase inhibitor (TKI), in a triple-negative, primary and metastatic breast cancer orthotopic model; potential molecular mechanisms of efficacy were also studied, especially the impact of hypoxic conditions. The combination of metronomic topotecan and pazopanib significantly enhanced antitumor activity compared to monotherapy with either drug and prolonged survival, even in the advanced metastatic survival setting, with a marked decrease in tumor vascularity, proliferative index, and the induction of apoptosis. Significant changes in tumor angiogenesis, cancer cell proliferation, apoptosis, HIF1? levels, HIF-1 target genes and ABCG2 were found both in vitro and in tumor tissue. Notably, the pazopanib and metronomic topotecan combination treatment inhibited expression of HIF1? and ABCG2 genes in cells grown under hypoxic conditions, and this was associated with an increased intracellular concentration of the active form of topotecan. Our results suggest a potential novel therapeutic option for the treatment of metastatic triple-negative breast cancer patients. PMID:26623560

  20. Potent efficacy of metronomic topotecan and pazopanib combination therapy in preclinical models of primary or late stage metastatic triple-negative breast cancer

    PubMed Central

    Man, Shan; Bocci, Guido; Kerbel, Robert S.

    2015-01-01

    Metronomic chemotherapy has shown promising activity in numerous preclinical studies and also some phase II clinical studies involving various tumor types, and is currently undergoing phase III trial evaluation. Triple-negative breast cancer (TNBC) is an aggressive histological subtype with limited treatment options and very poor prognosis following progression after standard chemotherapeutic regimens. Herein, we evaluated the potential therapeutic impact and molecular mechanisms of topotecan administered in a continuous low-dose metronomic (LDM) manner, alone or in concurrent combination with pazopanib, an antiangiogenic tyrosine kinase inhibitor (TKI), in a triple-negative, primary and metastatic breast cancer orthotopic model; potential molecular mechanisms of efficacy were also studied, especially the impact of hypoxic conditions. The combination of metronomic topotecan and pazopanib significantly enhanced antitumor activity compared to monotherapy with either drug and prolonged survival, even in the advanced metastatic survival setting, with a marked decrease in tumor vascularity, proliferative index, and the induction of apoptosis. Significant changes in tumor angiogenesis, cancer cell proliferation, apoptosis, HIF1α levels, HIF-1 target genes and ABCG2 were found both in vitro and in tumor tissue. Notably, the pazopanib and metronomic topotecan combination treatment inhibited expression of HIF1α and ABCG2 genes in cells grown under hypoxic conditions, and this was associated with an increased intracellular concentration of the active form of topotecan. Our results suggest a potential novel therapeutic option for the treatment of metastatic triple-negative breast cancer patients. PMID:26623560

  1. Preclinical studies of noncharged oxime reactivators for organophosphate exposure.

    PubMed

    Okolotowicz, Karl J; Dwyer, Mary; Smith, Emily; Cashman, John R

    2014-01-01

    A countermeasure that protects the brain from organophosphate toxicity is an unmet need. Few small molecule reactivators that can cross the blood brain barrier and reactivate brain acetyl cholinesterases have been reported. Herein, we describe preclinical investigations of a new class of amidine-oxime reactivator of cholinesterases with improved potency and blood brain barrier permeability. (Z)-N-((E)-1-(Dimethylamino)-2-(hydroxyimino)ethylidene)butan-1-aminium chloride, 1, is zwitterionic at physiological pH but possesses increased oxime nucleophilicity because of the adjacent amidine functionality. The amidine-oximes reported herein were observed to be nontoxic (up to 200 mg/kg in vivo) and are chemically and metabolically stable. The results presented herein show that uncharged amidine-oxime reactivators such as 1 can penetrate the blood brain barrier in animals and protect from the toxicity of nerve agent model compounds. PMID:23943350

  2. Enhanced preclinical efficacy of tamoxifen developed as alginate-cysteine/disulfide bond reduced albumin nanoparticles.

    PubMed

    Martnez, A; Muiz, E; Iglesias, I; Teijn, J M; Blanco, M D

    2012-10-15

    Tamoxifen (TMX) is the most common clinical choice for the treatment of advanced or metastatic estrogen-dependent breast cancer. However, research on new challenging therapies is necessary due to its undesirable side effects and the limitation of the treatment only to the oral route. In this study, the antitumor activity of TMX-loaded nanoparticles based on different mixtures of alginate-cysteine and disulfide bond reduced bovine serum albumin was tested in vivo in MCF-7 nude mice xenograft model. These systems showed an enhancement of the TMX antitumor activity, since lower tumor evolutions and lower tumor growth rates were observed in mice treated with them. Moreover, histological and immunohistochemical studies revealed that treatments with TMX-loaded nanoparticles showed the most regressive and less proliferative tumor tissues. TMX biodistribution studies determined that TMX-loaded nanoparticles caused more accumulation of the drug into the tumor site with undetectable levels of TMX in plasma, reducing the possibility of delivering TMX to other not-targeted organs and, consequently, developing possible side effects. Thus, these TMX nanoparticulate systems are expected to provide a novel approach to the treatment of breast cancer in the future. PMID:22850290

  3. Preclinical efficacy of maternal embryonic leucine-zipper kinase (MELK) inhibition in acute myeloid leukemia

    PubMed Central

    Alachkar, Houda; Mutonga, Martin B.G.; Metzeler, Klaus H.; Fulton, Noreen; Malnassy, Gregory; Herold, Tobias; Spiekermann, Karsten; Bohlander, Stefan K.; Hiddemann, Wolfgang; Matsuo, Yo; Stock, Wendy; Nakamura, Yusuke

    2014-01-01

    Maternal embryonic leucine-zipper kinase (MELK), which was reported to be frequently up-regulated in various types of solid cancer, plays critical roles in formation and maintenance of cancer stem cells. However, little is known about the relevance of this kinase in hematologic malignancies. Here we report characterization of possible roles of MELK in acute myeloid leukemia (AML). MELK is expressed in AML cell lines and AML blasts with higher levels in less differentiated cells. MELK is frequently upregulated in AML with complex karyotypes and is associated with worse clinical outcome. MELK knockdown resulted in growth inhibition and apoptosis of leukemic cells. Hence, we investigated the potent anti-leukemia activity of OTS167, a small molecule MELK kinase inhibitor, in AML, and found that the compound induced cell differentiation and apoptosis as well as decreased migration of AML cells. MELK expression was positively correlated with the expression of FOXM1 as well as its downstream target genes. Furthermore, MELK inhibition resulted in downregulation of FOXM1 activity and the expression of its downstream targets. Taken together, and given that OTS167 is undergoing a phase I clinical trial in solid cancer, our study warrants clinical evaluation of this compound as a novel targeted therapy for AML patients. PMID:25365263

  4. Preclinical Anticancer Efficacy of BET Bromodomain Inhibitors Is Determined by the Apoptotic Response.

    PubMed

    Conery, Andrew R; Centore, Richard C; Spillane, Kerry L; Follmer, Nicole E; Bommi-Reddy, Archana; Hatton, Charlie; Bryant, Barbara M; Greninger, Patricia; Amzallag, Arnaud; Benes, Cyril H; Mertz, Jennifer A; Sims, Robert J

    2016-03-15

    Small-molecule inhibitors of the bromodomain and extraterminal (BET) family of proteins are being tested in clinical trials for a variety of cancers, but patient selection strategies remain limited. This challenge is partly attributed to the heterogeneous responses elicited by BET inhibition (BETi), including cellular differentiation, senescence, and death. In this study, we performed phenotypic and gene-expression analyses of treatment-naive and engineered tolerant cell lines representing human melanoma and leukemia to elucidate the dominant features defining response to BETi. We found that de novo and acquired tolerance to BETi is driven by the robustness of the apoptotic response, and that genetic or pharmacologic manipulation of the apoptotic signaling network can modify the phenotypic response to BETi. We further reveal that the expression signatures of the apoptotic genes BCL2, BCL2L1, and BAD significantly predict response to BETi. Taken together, our findings highlight the apoptotic program as a determinant of response to BETi, and provide a molecular basis for patient stratification and combination therapy development. Cancer Res; 76(6); 1313-9. ©2016 AACR. PMID:26759243

  5. Copper-64 Dichloride as Theranostic Agent for Glioblastoma Multiforme: A Preclinical Study

    PubMed Central

    Ferrari, Cristina; Niccoli Asabella, Artor; Villano, Carlo; Giacobbi, Beatrice; Coccetti, Daniela; Panichelli, Paola; Rubini, Giuseppe

    2015-01-01

    Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults with a median survival time less than one year. To date, there are only a limited number of effective agents available for GBM therapy and this does not seem to add much survival advantage over the conventional approach based on surgery and radiotherapy. Therefore, the development of novel therapeutic approaches to GBM is essential and those based on radionuclide therapy could be of significant clinical impact. Experimental evidence has clearly demonstrated that cancer cells have a particularly high fractional content of copper inside the nucleus compared to normal cells. This behavior can be conveniently exploited both for diagnosis and for delivering therapeutic payloads (theranostic) of the radionuclide copper-64 into the nucleus of cancerous cells by intravenous administration of its simplest chemical form as dichloride salt [64Cu]CuCl2. To evaluate the potential theranostic role of [64Cu]CuCl2 in GBM, the present work reports results from a preclinical study carried out in a xenografted GBM tumor mouse model. Biodistribution data of this new agent were collected using a small-animal PET tomograph. Subsequently, groups of tumor implanted nude mice were treated with [64Cu]CuCl2 to simulate single- and multiple-dose therapy protocols, and results were analyzed to estimate therapeutic efficacy. PMID:26649294

  6. Racer efficacy study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Racer (ammonium nonanoate) is a non-selective contact herbicide that controls several weed species. Racer has been labeled by EPA in the past year for weed control in food crops and is close to receiving approval for use by organic producers. The objective of this study was to verify results from ...

  7. Paclitaxel and radiotherapy: sequence-dependent efficacy--a preclinical model.

    PubMed

    Niero, A; Emiliani, E; Monti, G; Pironi, F; Turci, L; Valenti, A M; Marangolo, M

    1999-08-01

    The optimal sequence of a paclitaxel-radiation combination was investigated in vitro in two human colon adenocarcinoma cell lines, HT29 and LoVo. Three schedules of combined treatment were tested by clonogenic and flow cytometric assays. Paclitaxel was given 24 h prior to a single radiation shot (first schedule) or 24 h (second schedule) or 48 h (third schedule) before 3 days of concomitant radiation. Dose-response data were fit to a linear quadratic model, and mean inactivation dose and sensitizer enhanced ratio were calculated. In HT29 cells, the first and second schedule resulted in an additive effect, whereas a supraadditive interaction was observed with the third combination schedule. This effect was obtained with amounts of paclitaxel lower than IC50, which did not result in cell cycle perturbation, and with low radiation dose (2 Gy) that may be given in a clinical setting. LoVo cells were less sensitive to combined treatment than HT29 cells, switching from infraadditive (first and second schedule) to additive interaction (third schedule). Posttreatment recovery studies of third schedule showed a loss of cell survival in HT29 cells but not in LoVo cells. In contrast to LoVo cells, the third schedule in HT29 cells was able to induce perturbation of cell cycle kinetics, an effective impairment of DNA repair, and apoptotic cell death. HT29 and LoVo cells showed constitutional different characteristics: HT29 cells were more sensitive to paclitaxel exposure, less radiosensitive, and had a different cell cycle redistribution after radiation exposure than LoVo cells; moreover, HT29 cells showed a major propensity to undergo apoptosis. These results suggest that the radiosensitizing effect of paclitaxel was strictly schedule dependent, and the inhibition of DNA repair, cell cycle redistribution, and apoptosis could be the mechanisms for the induction of radiosensitization by paclitaxel. PMID:10473108

  8. Preclinical evaluation of efficacy and safety of an improved lentiviral vector for the treatment of ?-thalassemia and sickle cell disease.

    PubMed

    Negre, Olivier; Bartholomae, Cynthia; Beuzard, Yves; Cavazzana, Marina; Christiansen, Lauryn; Courne, Cline; Deichmann, Annette; Denaro, Maria; de Dreuzy, Edouard; Finer, Mitchell; Fronza, Raffaele; Gillet-Legrand, Batrix; Joubert, Christophe; Kutner, Robert; Leboulch, Philippe; Maouche, Lela; Paulard, Anas; Pierciey, Francis J; Rothe, Michael; Ryu, Byoung; Schmidt, Manfred; von Kalle, Christof; Payen, Emmanuel; Veres, Gabor

    2015-01-01

    A previously published clinical trial demonstrated the benefit of autologous CD34(+) cells transduced with a selfinactivating lentiviral vector (HPV569) containing an engineered ?-globin gene (?(A-T87Q)-globin) in a subject with ? thalassemia major. This vector has been modified to increase transduction efficacy without compromising safety. In vitro analyses indicated that the changes resulted in both increased vector titers (3 to 4 fold) and increased transduction efficacy (2 to 3 fold). An in vivo study in which 58 ?-thalassemic mice were transplanted with vector- or mock-transduced syngenic bone marrow cells indicated sustained therapeutic efficacy. Secondary transplantations involving 108 recipients were performed to evaluate long-term safety. The six month study showed no hematological or biochemical toxicity. Integration site (IS) profile revealed an oligo/polyclonal hematopoietic reconstitution in the primary transplants and reduced clonality in secondary transplants. Tumor cells were detected in the secondary transplant mice in all treatment groups (including the control group), without statistical differences in the tumor incidence. Immunohistochemistry and quantitative PCR demonstrated that tumor cells were not derived from transduced donor cells. This comprehensive efficacy and safety data provided the basis for initiating two clinical trials with this second generation vector (BB305) in Europe and in the USA in patients with ?-thalassemia major and sickle cell disease. PMID:25429463

  9. What level of accuracy is achievable for preclinical dose painting studies on a clinical irradiation platform?

    PubMed

    Trani, Daniela; Reniers, Brigitte; Persoon, Lucas; Podesta, Mark; Nalbantov, Georgi; Leijenaar, Ralph T H; Granzier, Marlies; Yaromina, Ala; Dubois, Ludwig; Verhaegen, Frank; Lambin, Philippe

    2015-05-01

    Advancements made over the past decades in both molecular imaging and radiotherapy planning and delivery have enabled studies that explore the efficacy of heterogeneous radiation treatment ("dose painting") of solid cancers based on biological information provided by different imaging modalities. In addition to clinical trials, preclinical studies may help contribute to identifying promising dose painting strategies. The goal of this current study was twofold: to develop a reproducible positioning and set-up verification protocol for a rat tumor model to be imaged and treated on a clinical platform, and to assess the dosimetric accuracy of dose planning and delivery for both uniform and positron emission tomography-computed tomography (PET-CT) based heterogeneous dose distributions. We employed a syngeneic rat rhabdomyosarcoma model, which was irradiated by volumetric modulated arc therapy (VMAT) with uniform or heterogeneous 6 MV photon dose distributions. Mean dose to the gross tumor volume (GTV) as a whole was kept at 12 Gy for all treatment arms. For the nonuniform plans, the dose was redistributed to treat the 30% of the GTV representing the biological target volume (BTV) with a dose 40% higher than the rest of the GTV (GTV - BTV) (~15 Gy was delivered to the BTV vs. ~10.7 Gy was delivered to the GTV - BTV). Cone beam computed tomography (CBCT) images acquired for each rat prior to irradiation were used to correctly reposition the tumor and calculate the delivered 3D dose. Film quality assurance was performed using a water-equivalent rat phantom. A comparison between CT or CBCT doses and film measurements resulted in passing rates >98% with a gamma criterion of 3%/2 mm using 2D dose images. Moreover, between the CT and CBCT calculated doses for both uniform and heterogeneous plans, we observed maximum differences of <2% for mean dose to the tumor and mean dose to the biological target volumes. In conclusion, we have developed a robust method for dose painting in a rat tumor model on a clinical platform, with a high accuracy achieved in the delivery of complex dose distributions. Our work demonstrates the technical feasibility of this approach and enables future investigations on the therapeutic effect of preclinical dose painting strategies using a state-of-the-art clinical platform. PMID:25897556

  10. Magnetic Fluid Hyperthermia for Bladder Cancer: A Preclinical Dosimetry Study

    PubMed Central

    Oliveira, Tiago R.; Stauffer, Paul R.; Lee, Chen-Ting; Landon, Chelsea D.; Etienne, Wiguins; Ashcraft, Kathleen A.; McNerny, Katie L.; Mashal, Alireza; Nouls, John; Maccarini, Paolo F.; Beyer, Wayne F.; Inman, Brant; Dewhirst, Mark W.

    2014-01-01

    Purpose This paper describes a preclinical investigation of the feasibility of thermotherapy treatment of bladder cancer with Magnetic Fluid Hyperthermia (MFH), performed by analyzing the thermal dosimetry of nanoparticle heating in a rat bladder model. Materials and Methods The bladders of twenty-five female rats were instilled with magnetite-based nanoparticles, and hyperthermia was induced using a novel small animal magnetic field applicator (Actium Biosystems, Boulder, CO). We aimed to increase the bladder lumen temperature to 42°C in <10 min and maintain that temperature for 60 min. Temperatures were measured within the bladder lumen and throughout the rat with seven fiberoptic probes (OpSens Technologies, Quebec, Canada). An MRI analysis was used to confirm the effectiveness of the catheterization method to deliver and maintain various nanoparticle volumes within the bladder. Thermal dosimetry measurements recorded the temperature rise of rat tissues for a variety of nanoparticle exposure conditions. Results Thermal dosimetry data demonstrated our ability to raise and control the temperature of rat bladder lumen ≥1°C/min to a steady-state of 42°C with minimal heating of surrounding normal tissues. MRI scans confirmed the homogenous nanoparticle distribution throughout the bladder. Conclusion These data demonstrate that our MFH system with magnetite-based nanoparticles provide well-localized heating of rat bladder lumen with effective control of temperature in the bladder and minimal heating of surrounding tissues. PMID:24050253

  11. Preclinical gene therapy studies for hemophilia using adenoviral vectors.

    PubMed

    Thorrez, Lieven; VandenDriessche, Thierry; Collen, Dsir; Chuah, Marinee K

    2004-04-01

    Hemophilia A and B are hereditary coagulation defects resulting from a deficiency of factor VIII (FVIII) and factor IX (FIX), respectively. Introducing a functional FVIII or FIX gene could potentially provide a cure for these bleeding disorders. Adenoviral vectors have been used as tools to introduce potentially therapeutic genes into mammalian cells and are by far the most efficient vectors for hepatic gene delivery. Long-term expression of both FVIII and FIX has been achieved in preclinical (hemophilic) mouse models using adenoviral vectors. Therapeutic levels of FVIII and FIX also have been achieved in hemophilic dogs using adenoviral vectors and in some cases expression was long-term. The performance of earlier generation adenoviral vectors, which retained residual viral genes, was compromised by potent acute and chronic inflammatory responses that contributed to significant toxicity and morbidity and short-term expression of FVIII and FIX. The development of improved adenoviral vectors devoid of viral genes (gutless or high-capacity adenoviral vectors) was therefore warranted, which led to a significant reduction in acute and chronic toxicity and more prolonged expression of FVIII and FIX. Strategies aimed at making these vectors safer and less immunogenic and their implications for hemophilia gene therapy are discussed in this review. PMID:15118929

  12. Investigating the Efficacy of Practical Skill Teaching: A Pilot-Study Comparing Three Educational Methods

    ERIC Educational Resources Information Center

    Maloney, Stephen; Storr, Michael; Paynter, Sophie; Morgan, Prue; Ilic, Dragan

    2013-01-01

    Effective education of practical skills can alter clinician behaviour, positively influence patient outcomes, and reduce the risk of patient harm. This study compares the efficacy of two innovative practical skill teaching methods, against a traditional teaching method. Year three pre-clinical physiotherapy students consented to participate in a

  13. Investigating the Efficacy of Practical Skill Teaching: A Pilot-Study Comparing Three Educational Methods

    ERIC Educational Resources Information Center

    Maloney, Stephen; Storr, Michael; Paynter, Sophie; Morgan, Prue; Ilic, Dragan

    2013-01-01

    Effective education of practical skills can alter clinician behaviour, positively influence patient outcomes, and reduce the risk of patient harm. This study compares the efficacy of two innovative practical skill teaching methods, against a traditional teaching method. Year three pre-clinical physiotherapy students consented to participate in a…

  14. Pre-clinical immunotoxicity studies of nanotechnology-formulated drugs: Challenges, considerations and strategy.

    PubMed

    Dobrovolskaia, Marina A

    2015-12-28

    Assorted challenges in physicochemical characterization, sterilization, depyrogenation, and in the assessment of pharmacology, safety, and efficacy profiles accompany pre-clinical development of nanotechnology-formulated drugs. Some of these challenges are not unique to nanotechnology and are common in the development of other pharmaceutical products. However, nanoparticle-formulated drugs are biochemically sophisticated, which causes their translation into the clinic to be particularly complex. An understanding of both the immune compatibility of nanoformulations and their effects on hematological parameters is now recognized as an important step in the (pre)clinical development of nanomedicines. An evaluation of nanoparticle immunotoxicity is usually performed as a part of a traditional toxicological assessment; however, it often requires additional in vitro and in vivo specialized immuno- and hematotoxicity tests. Herein, I review literature examples and share the experience with the NCI Nanotechnology Characterization Laboratory assay cascade used in the early (discovery-level) phase of pre-clinical development to summarize common challenges in the immunotoxicological assessment of nanomaterials, highlight considerations and discuss solutions to overcome problems that commonly slow or halt the translation of nanoparticle-formulated drugs toward clinical trials. Special attention will be paid to the grand-challenge related to detection, quantification and removal of endotoxin from nanoformulations, and practical considerations related to this challenge. PMID:26348388

  15. Pre-clinical and Clinical Safety Studies of CMX-2043: a cytoprotective lipoic acid analogue for ischaemia-reperfusion injury.

    PubMed

    Kates, Steven A; Lader, Alan S; Casale, Ralph; Beeuwkes, Reinier

    2014-11-01

    CMX-2043 is an ?-lipoic acid analogue targeted to reduction of cellular injury and organ damage due to ischaemia-reperfusion injury (IRI). It has been shown to be effective in a rat model of cardiac IRI. The studies here reported evaluate its safety and pharmacokinetic profile in preparation for human clinical studies in procedures associated with IRI. Safety and tolerability were tested in standard pre-clinical in vitro and animal models and in a Phase 1 human clinical trial. CMX-2043 did not bind to a wide range of receptors and specific targets at approximately 4?g/mL (10?M). It was not mutagenic by Ames assay, did not produce chromosome aberrations in Chinese hamster ovary (CHO) cells, and was negative for clastogenic potential. Toxicological studies in rats including both single and 14-day repeat intravenous doses and in dogs (single intravenous dose) with a 2-week recovery period were conducted. The NOAEL in rats and dogs was 30 and >10mg/kg, respectively. No serious adverse events were reported in a placebo-controlled, sequential dose escalation Phase 1 clinical trial. The low toxicity in the pre-clinical studies and the absence of adverse events in the Phase 1 trial have supported investigation of CMX-2043 in a human efficacy trial. PMID:24751172

  16. Pre-clinical and Clinical Safety Studies of CMX-2043: A Cytoprotective Lipoic Acid Analogue for IschaemiaReperfusion Injury

    PubMed Central

    Kates, Steven A; Lader, Alan S; Casale, Ralph; Beeuwkes, Reinier

    2014-01-01

    CMX-2043 is an ?-lipoic acid analogue targeted to reduction of cellular injury and organ damage due to ischaemiareperfusion injury (IRI). It has been shown to be effective in a rat model of cardiac IRI. The studies here reported evaluate its safety and pharmacokinetic profile in preparation for human clinical studies in procedures associated with IRI. Safety and tolerability were tested in standard pre-clinical in vitro and animal models and in a Phase 1 human clinical trial. CMX-2043 did not bind to a wide range of receptors and specific targets at approximately 4?g/mL (10?M). It was not mutagenic by Ames assay, did not produce chromosome aberrations in Chinese hamster ovary (CHO) cells, and was negative for clastogenic potential. Toxicological studies in rats including both single and 14-day repeat intravenous doses and in dogs (single intravenous dose) with a 2-week recovery period were conducted. The NOAEL in rats and dogs was 30 and >10mg/kg, respectively. No serious adverse events were reported in a placebo-controlled, sequential dose escalation Phase 1 clinical trial. The low toxicity in the pre-clinical studies and the absence of adverse events in the Phase 1 trial have supported investigation of CMX-2043 in a human efficacy trial. PMID:24751172

  17. Preclinical toxicity evaluation of AAV for pain: evidence from human AAV studies and from the pharmacology of analgesic drugs

    PubMed Central

    2014-01-01

    Gene therapy with adeno-associated virus (AAV) has advanced in the last few years from promising results in animal models to >100 clinical trials (reported or under way). While vector availability was a substantial hurdle a decade ago, innovative new production methods now routinely match the scale of AAV doses required for clinical testing. These advances may become relevant to translational research in the chronic pain field. AAV for pain targeting the peripheral nervous system was proven to be efficacious in rodent models several years ago, but has not yet been tested in humans. The present review addresses the steps needed for translation of AAV for pain from the bench to the bedside focusing on pre-clinical toxicology. We break the potential toxicities into three conceptual categories of risk: First, risks related to the delivery procedure used to administer the vector. Second, risks related to AAV biology, i.e., effects of the vector itself that may occur independently of the transgene. Third, risks related to the effects of the therapeutic transgene. To identify potential toxicities, we consulted the existing evidence from AAV gene therapy for other nervous system disorders (animal toxicology and human studies) and from the clinical pharmacology of conventional analgesic drugs. Thereby, we identified required preclinical studies and charted a hypothetical path towards a future phase I/II clinical trial in the oncology-palliative care setting. PMID:25183392

  18. Focused ultrasound-induced blood-brain barrier opening to enhance temozolomide delivery for glioblastoma treatment: a preclinical study.

    PubMed

    Wei, Kuo-Chen; Chu, Po-Chun; Wang, Hay-Yan Jack; Huang, Chiung-Yin; Chen, Pin-Yuan; Tsai, Hong-Chieh; Lu, Yu-Jen; Lee, Pei-Yun; Tseng, I-Chou; Feng, Li-Ying; Hsu, Peng-Wei; Yen, Tzu-Chen; Liu, Hao-Li

    2013-01-01

    The purpose of this study is to assess the preclinical therapeutic efficacy of magnetic resonance imaging (MRI)-monitored focused ultrasound (FUS)-induced blood-brain barrier (BBB) disruption to enhance Temozolomide (TMZ) delivery for improving Glioblastoma Multiforme (GBM) treatment. MRI-monitored FUS with microbubbles was used to transcranially disrupt the BBB in brains of Fisher rats implanted with 9L glioma cells. FUS-BBB opening was spectrophotometrically determined by leakage of dyes into the brain, and TMZ was quantitated in cerebrospinal fluid (CSF) and plasma by LC-MS\\MS. The effects of treatment on tumor progression (by MRI), animal survival and brain tissue histology were investigated. Results demonstrated that FUS-BBB opening increased the local accumulation of dyes in brain parenchyma by 3.8-/2.1-fold in normal/tumor tissues. Compared to TMZ alone, combined FUS treatment increased the TMZ CSF/plasma ratio from 22.7% to 38.6%, reduced the 7-day tumor progression ratio from 24.03 to 5.06, and extended the median survival from 20 to 23 days. In conclusion, this study provided preclinical evidence that FUS BBB-opening increased the local concentration of TMZ to improve the control of tumor progression and animal survival, suggesting its clinical potential for improving current brain tumor treatment. PMID:23527068

  19. Exploratory Study of Factors Related to Educational Scores of First Preclinical Year Medical Students

    ERIC Educational Resources Information Center

    Sitticharoon, Chantacha; Srisuma, Sorachai; Kanavitoon, Sawita; Summachiwakij, Sarawut

    2014-01-01

    The relationships among the scores of major subjects taught in the first preclinical year of a Thai medical school, previous academic achievements, and daily life activities are rarely explored. We therefore performed an exploratory study identifying various factors possibly related to the educational scores of these medical students.…

  20. Preclinical studied of general toxic properties of preparations containing ultralow doses of antibodies to endogenous regulators.

    PubMed

    Karpova, G V; Fomina, T I; Vetoshkina, T V; Dubskaya, T Yu; Voronova, O L; Timina, E A; Abramova, E V; Ermolaeva, L A; Perova, A V

    2009-09-01

    Preclinical study of the safety of 6 preparations containing ultralow doses of antibodies to endogenous regulators showed that they are relatively safe, are well tolerated by animals in doses more than 1000-fold surpassing the therapeutic dose for humans, and produce no general toxic effect on the organism of laboratory animals. PMID:20396736

  1. Exploratory Study of Factors Related to Educational Scores of First Preclinical Year Medical Students

    ERIC Educational Resources Information Center

    Sitticharoon, Chantacha; Srisuma, Sorachai; Kanavitoon, Sawita; Summachiwakij, Sarawut

    2014-01-01

    The relationships among the scores of major subjects taught in the first preclinical year of a Thai medical school, previous academic achievements, and daily life activities are rarely explored. We therefore performed an exploratory study identifying various factors possibly related to the educational scores of these medical students.

  2. Meta-analysis of preclinical studies of mesenchymal stromal cells for ischemic stroke

    PubMed Central

    Vu, Quynh; Xie, Kate; Eckert, Mark; Zhao, Weian

    2014-01-01

    Objectives: To evaluate the quality of preclinical evidence for mesenchymal stromal cell (MSC) treatment of ischemic stroke, determine effect size of MSC therapy, and identify clinical measures that correlate with differences in MSC effects. Methods: A literature search identified studies of MSCs in animal models of cerebral ischemia. For each, a Quality Score was derived, and effect size of MSCs was determined for the most common behavioral and histologic endpoints. Results: Of 46 studies, 44 reported that MSCs significantly improved outcome. The median Quality Score was 5.5 (of 10). The median effect size was 1.78 for modified Neurological Severity Score, 1.73 for the adhesive removal test, 1.02 for the rotarod test, and 0.93 for infarct volume reduction. Quality Score correlated significantly and positively with effect size for the modified Neurological Severity Score. Effect sizes varied significantly with clinical measures such as administration route (intracerebral > intra-arterial > IV, although effect size for IV was nonetheless very large at 1.55) and species receiving MSCs (primate > rat > mouse). Because many MSC mechanisms are restorative, analyses were repeated examining only the 36 preclinical studies administering MSCs ≥24 hours poststroke; results were overall very similar. Conclusions: In preclinical studies, MSCs have consistently improved multiple outcome measures, with very large effect sizes. Results were robust across species studied, administration route, species of MSC origin, timing, degree of immunogenicity, and dose, and in the presence of comorbidities. In contrast to meta-analyses of preclinical data for other stroke therapies, higher-quality MSC preclinical studies were associated with larger behavioral gains. These findings support the utility of further studies to translate MSCs in the treatment of ischemic stroke in humans. PMID:24610327

  3. The Relationship between Risk of Bias Criteria, Research Outcomes, and Study Sponsorship in a Cohort of Preclinical Thiazolidinedione Animal Studies: A Meta-Analysis

    PubMed Central

    Abdel-Sattar, Maher; Krauth, David; Anglemyer, Andrew; Bero, Lisa

    2015-01-01

    Introduction There is little evidence regarding the influence of conflicts of interest on preclinical research. This study examines whether industry sponsorship is associated with increased risks of bias and/or effect sizes of outcomes in published preclinical thiazolidinedione (TZD) studies. Methods We identified preclinical TZD studies published between January 1, 1965 and November 14, 2012. Coders independently extracted information on study design criteria aimed at reducing bias, results for all relevant outcomes, sponsorship source, and investigator financial ties from the 112 studies meeting the inclusion criteria. The average standardized mean difference (SMD) across studies was calculated for plasma glucose (efficacy outcome) and weight gain (harm outcome). In subgroup analyses, TZD outcomes were assessed by sponsorship source and risk of bias criteria. Results Seven studies were funded by industry alone, 17 studies funded by both industry and non-industry, 49 studies funded by non-industry alone, and 39 studies had no disclosures. None of the studies used sample size calculations, intention-to-treat analyses, blinding of investigators, or concealment of allocation. Most studies reported favorable results (88 of 112) and conclusions (95 of 112) supporting TZD use. Efficacy estimates were significantly larger in 6 studies sponsored by industry alone (−3.41; 95% CI −5.21, −1.53; I2 = 93%) versus 42 studies sponsored by non-industry sources (−0.97; 95% CI −1.37, −0.56; I2 = 81%) (p value = 0.01). Harms estimates were significantly larger in 4 studies sponsored by industry alone (5.00; 95% CI 1.22, 8.77; I2 = 93%) versus 38 studies sponsored by non-industry sources (0.30; 95% CI −0.08, 0.68; I2 = 79%) (p value = 0.02). TZD efficacy and harms did not differ by disclosure of financial COIs or risks of bias. Conclusions Industry-sponsored TZD animal studies have exaggerated efficacy and harms outcomes compared to studies funded by non-industry sources. There was poor reporting of COIs. PMID:25642330

  4. BLOCKING CANNABINOID CB1 RECEPTORS FOR THE TREATMENT OF NICOTINE DEPENDENCE: INSIGHTS FROM PRECLINICAL AND CLINICAL STUDIES

    PubMed Central

    Le Foll, Bernard; Forget, Benoit; Aubin, Henri-Jean; Goldberg, Steven R.

    2009-01-01

    Tobacco use is one of the leading preventable causes of death in developed countries. Since existing medications are only partially effective in treating tobacco smokers, there is a great need for improved medications for smoking cessation. It has been recently proposed that cannabinoid CB1 receptor antagonists represent a new class of therapeutic agents for drug dependence, and, notably, nicotine dependence. Here, we will review current evidence supporting the use of this class of drugs for smoking cessation treatment. Preclinical studies indicate that nicotine exposure produces changes in endocannabinoid content in the brain. In experimental animals, Rimonabant (SR141716) and AM251, two cannabinoid CB1 receptor antagonists, block nicotine self-administration behavior, an effect that may be related to the blockade of the dopamine-releasing effects of nicotine in the brain. Rimonabant also seems efficacious in decreasing the influence of nicotine-associated stimuli over behavior, suggesting that it may act on two distinct neuronal pathways, those implicated in drug-taking behavior and those involved in relapse phenomena. The utility of Rimonabant has been evaluated in several clinical trials. It seems that Rimonabant is an efficacious treatment for smoking cessation, although its efficacy doesn’t exceed that of nicotine replacement therapy and its use may be limited by emotional side effects (nausea, anxiety and depression, mostly). Rimonabant also appears to decrease relapse rates in smokers. These findings indicate significant, but limited, utility of Rimonabant for smoking cessation. PMID:18482433

  5. Plant-based medicines for anxiety disorders, part 2: a review of clinical studies with supporting preclinical evidence.

    PubMed

    Sarris, Jerome; McIntyre, Erica; Camfield, David A

    2013-04-01

    Research in the area of herbal psychopharmacology has revealed a variety of promising medicines that may provide benefit in the treatment of general anxiety and specific anxiety disorders. However, a comprehensive review of plant-based anxiolytics has been absent to date. Thus, our aim was to provide a comprehensive narrative review of plant-based medicines that have clinical and/or preclinical evidence of anxiolytic activity. We present the article in two parts. In part one, we reviewed herbal medicines for which only preclinical investigations for anxiolytic activity have been performed. In this current article (part two), we review herbal medicines for which there have been both preclinical and clinical investigations of anxiolytic activity. A search of MEDLINE (PubMed), CINAHL, Scopus and the Cochrane Library databases was conducted (up to 28 October 2012) for English language papers using the search terms 'anxiety' OR 'anxiety disorder' OR 'generalized anxiety disorder' OR 'social phobia' OR 'post-traumatic stress disorder' OR 'panic disorder' OR 'agoraphobia' OR 'obsessive compulsive disorder' in combination with the search terms 'Herb*' OR 'Medicinal Plants' OR 'Botanical Medicine' OR 'Chinese herb*', in addition to individual herbal medicines. This search of the literature revealed 1,525 papers, of which 53 plants were included in the review (having at least one study using the whole plant extract). Of these plants, 21 had human clinical trial evidence (reviewed here in part two), with the other 32 having solely preclinical evidence (reviewed in part one). Support for efficacy was found for chronic use (i.e. greater than one day) of the following herbs in treating a range of anxiety disorders in human clinical trials: Piper methysticum, Matricaria recutita, Ginkgo biloba, Scutellaria lateriflora, Silybum marianum, Passiflora incarnata, Withania somniferum, Galphimia glauca, Centella asiatica, Rhodiola rosea, Echinacea spp., Melissa officinalis and Echium amoenum. For several of the plants studied, conclusions need to be tempered due to methodological issues such as small sample sizes, brief intervention durations and non-replication. Current evidence does not support Hypericum perforatum or Valeriana spp. for any anxiety disorder. Acute anxiolytic activity was found for Centella asiatica, Salvia spp., Melissa officinalis, Passiflora incarnata and Citrus aurantium. Bacopa monnieri has shown anxiolytic effects in people with cognitive decline. The therapeutic application of psychotropic plant-based treatments for anxiety disorders is also discussed, specifically Psychotria viridis and Banisteriopsis caarti (ayahuasca), Psilocybe spp. and cannabidiol-enriched (low tetrahydrocannabinol (?(9)-THC)) Cannabis spp. PMID:23653088

  6. Spinal Cord Tolerance in the Age of Spinal Radiosurgery: Lessons From Preclinical Studies

    SciTech Connect

    Medin, Paul M.; Boike, Thomas P.

    2011-04-01

    Clinical implementation of spinal radiosurgery has increased rapidly in recent years, but little is known regarding human spinal cord tolerance to single-fraction irradiation. In contrast, preclinical studies in single-fraction spinal cord tolerance have been ongoing since the 1970s. The influences of field length, dose rate, inhomogeneous dose distributions, and reirradiation have all been investigated. This review summarizes literature regarding single-fraction spinal cord tolerance in preclinical models with an emphasis on practical clinical significance. The outcomes of studies that incorporate uniform irradiation are surprisingly consistent among multiple small- and large-animal models. Extensive investigation of inhomogeneous dose distributions in the rat has demonstrated a significant dose-volume effect while preliminary results from one pig study are contradictory. Preclinical spinal cord dose-volume studies indicate that dose distribution is more critical than the volume irradiated suggesting that neither dose-volume histogram analysis nor absolute volume constraints are effective in predicting complications. Reirradiation data are sparse, but results from guinea pig, rat, and pig studies are consistent with the hypothesis that the spinal cord possesses a large capacity for repair. The mechanisms behind the phenomena observed in spinal cord studies are not readily explained and the ability of dose response models to predict outcomes is variable underscoring the need for further investigation. Animal studies provide insight into the phenomena and mechanisms of radiosensitivity but the true significance of animal studies can only be discovered through clinical trials.

  7. Nefopam analgesia and its role in multimodal analgesia: A review of preclinical and clinical studies.

    PubMed

    Girard, Philippe; Chauvin, Marcel; Verleye, Marc

    2016-01-01

    Nefopam is a non-opioid, non-steroidal, centrally acting analgesic drug used to prevent postoperative pain, primarily in the context of multimodal analgesia. This paper reviews preclinical and clinical studies in which nefopam has been combined with opioids, non-steroidal anti-inflammatory compounds, and paracetamol. This report focuses on the literature during the last decade and discusses the translational efforts between animal and clinical studies in the context of multimodal or balanced analgesia. In preclinical rodent models of acute and inflammatory pain, nefopam combinations including opioids revealed a synergistic interaction or enhanced morphine analgesia in six out of seven studies. Nefopam combinations including non-steroidal anti-inflammatory drugs (NSAIDs) (aspirin, ketoprofen or nimesulide) or paracetamol likewise showed enhanced analgesic effects for the associated compound in all instances. Clinical studies have been performed in various types of surgeries involving different pain intensities. Nefopam combinations including opioids resulted in a reduction in morphine consumption in 8 out of 10 studies of severe or moderate pain. Nefopam combinations including NSAIDs (ketoprofen or tenoxicam) or paracetamol also demonstrated a synergic interaction or an enhancement of the analgesic effect of the associated compound. In conclusion, this review of nefopam combinations including various analgesic drugs (opioids, NSAIDs and paracetamol) reveals that enhanced analgesia was demonstrated in most preclinical and clinical studies, suggesting a role for nefopam in multimodal analgesia based on its distinct characteristics as an analgesic. Further clinical studies are needed to evaluate the analgesic effects of nefopam combinations including NSAIDs or paracetamol. PMID:26475417

  8. From Bench to Bedside: Lessons Learned in Translating Preclinical Studies in Cancer Drug Development

    PubMed Central

    2013-01-01

    The development of targeted agents in oncology has rapidly expanded over the past 2 decades and has led to clinically significant improvements in the treatment of numerous cancers. Unfortunately, not all success at the bench in preclinical experiments has translated to success at the bedside. As preclinical studies shift toward defining proof of mechanism, patient selection, and rational drug combinations, it is critical to understand the lessons learned from prior translational studies to gain an understanding of prior drug development successes and failures. By learning from prior drug development, future translational studies will provide more clinically relevant data, and the underlying hope is that the clinical success rate will improve and the treatment of patients with ineffective targeted therapy will be limited. PMID:24052618

  9. Preclinical studies of N3-O-toluyl-fluorouracil-loaded lipid-based nanosuspensions in H22-bearing mice

    PubMed Central

    Zhang, Juan; Li, Min; Liu, Zhihong; Wang, Lili; Liu, Yongjun; Zhang, Na

    2014-01-01

    Purpose N3-O-toluyl-fluorouracil (TFU) is a potential antitumor prodrug of 5-fluorouracil (5-FU), but its poor solubility has limited its use in clinic. This study aimed to improve the bioavailability of TFU by preparing TFU-loaded lipid-based nanosuspensions (TFU-LNS) and perform a preclinical evaluation. Methods TFU-LNS were prepared through high-pressure homogenization and were lyophilized afterwards. For in vitro test, the physicochemical properties and cytotoxicity against HegG2 cells were conducted. For in vivo evaluation, the pharmacokinetics, tissue distribution, and antitumor efficacy were investigated in H22-bearing Kunming mice. Results TFU showed different degradability in four media; in particular, nearly all of it converted to an equimolar amount of 5-FU in blank plasma of Wistar rats. The lyophilized TFU-LNS had a mean particle size of 180.03±3.11 nm and zeta potential of −8.02±1.43 mV and showed no discernible changes after storage at 4°C for 3 months. In the in vivo antitumor study, the antitumor efficacy of TFU-LNS was consistent with that of 5-FU injection. Furthermore, TFU-LNS released a lower concentration of 5-FU in heart and kidney throughout the tissue distribution studies. Conclusion TFU-LNS exhibited convincing antitumor activity and easy scale-up opportunity, which suggests that TFU-LNS might be a promising drug delivery system for cancer therapy. PMID:24920908

  10. Preclinical and Clinical Studies for Sodium Tungstate: Application in Humans

    PubMed Central

    Bertinat, Romina; Nualart, Francisco; Li, Xuhang; Yáñez, Alejandro J.; Gomis, Ramón

    2015-01-01

    Diabetes is a complex metabolic disorder triggered by the deficient secretion of insulin by the pancreatic β-cell or the resistance of peripheral tissues to the action of the hormone. Chronic hyperglycemia is the major consequence of this failure, and also the main cause of diabetic problems. Indeed, several clinical trials have agreed in that tight glycemic control is the best way to stop progression of the disease. Many anti-diabetic drugs for treatment of type 2 diabetes are commercially available, but no ideal normoglycemic agent has been developed yet. Moreover, weight gain is the most common side effect of many oral anti-diabetic agents and insulin, and increased weight has been shown to worsen glycemic control and increase the risk of diabetes progression. In this sense, the inorganic salt sodium tungstate (NaW) has been studied in different animal models of metabolic syndrome and diabetes, proving to have a potent effect on normalizing blood glucose levels and reducing body weight, without any hypoglycemic action. Although the liver has been studied as the main site of NaW action, positive effects have been also addressed in muscle, pancreas, brain, adipose tissue and intestine, explaining the effective anti-diabetic action of this salt. Here, we review NaW research to date in these different target organs. We believe that NaW deserves more attention, since all available anti-diabetic treatments remain suboptimal and new therapeutics are urgently needed. PMID:25995968

  11. Anticancer potential of curcumin: preclinical and clinical studies.

    PubMed

    Aggarwal, Bharat B; Kumar, Anushree; Bharti, Alok C

    2003-01-01

    Curcumin (diferuloylmethane) is a polyphenol derived from the plant Curcuma longa, commonly called turmeric. Extensive research over the last 50 years has indicated this polyphenol can both prevent and treat cancer. The anticancer potential of curcumin stems from its ability to suppress proliferation of a wide variety of tumor cells, down-regulate transcription factors NF-kappa B, AP-1 and Egr-1; down-regulate the expression of COX2, LOX, NOS, MMP-9, uPA, TNF, chemokines, cell surface adhesion molecules and cyclin D1; down-regulate growth factor receptors (such as EGFR and HER2); and inhibit the activity of c-Jun N-terminal kinase, protein tyrosine kinases and protein serine/threonine kinases. In several systems, curcumin has been described as a potent antioxidant and anti-inflammatory agent. Evidence has also been presented to suggest that curcumin can suppress tumor initiation, promotion and metastasis. Pharmacologically, curcumin has been found to be safe. Human clinical trials indicated no dose-limiting toxicity when administered at doses up to 10 g/day. All of these studies suggest that curcumin has enormous potential in the prevention and therapy of cancer. The current review describes in detail the data supporting these studies. PMID:12680238

  12. Technetium-99m galactosyl-neoglycoalbumin: preparation and preclinical studies

    SciTech Connect

    Vera, D.R.; Stadalnik, R.C.; Krohn, K.A.

    1985-10-01

    Technetium-99m galactosyl-neoglycoalbumin ((Tc) NGA), a labeled analog ligand to the hepatocyte-specific receptor, hepatic binding protein (HBP), was prepared and tested for labeling yield, stability, biodistribution, toxicity, and dosimetry. The ligand was synthesized by the covalent coupling of a carbohydrate bifunctional reagent, 2-imino-2-ethyloxymethyl-1-thiogalactose, to human serum albumin. Testing in mice and rabbits revealed the product to be nontoxic and apyrogenic. Biodistribution studies in rabbits demonstrated the liver as the single focus of tracer uptake. Dosimetry was based on kinetic studies in three baboons. Absorbed doses to liver, small intestine, urinary bladder wall, and uterus were 0.089, 0.28, 0.56, and 0.88 rad/mCi, respectively. Total body, lens of the eye, red marrow, ovaries, and testes were less than 0.06 rad/mCi. High liver specificity imparted by receptor binding combined with high labeling yield, stability, acceptable dosimetry, and safety provide (Tc)NGA with the attributes required for routine clinical assessment of hepatocyte function.

  13. Endpoint measures in the mdx mouse relevant for muscular dystrophy pre-clinical studies

    PubMed Central

    Kobayashi, Yvonne M.; Rader, Erik P.; Crawford, Robert W.; Campbell, Kevin P.

    2011-01-01

    Loss of mobility influences the quality of life for patients with neuromuscular diseases. Common measures of mobility and chronic muscle damage are the six-minute walk test and serum creatine kinase. Despite extensive pre-clinical studies of therapeutic approaches, characterization of these measures is incomplete. To address this, a six-minute ambulation assay, serum creatine kinase, and myoglobinuria were investigated for the mdx mouse, a dystrophinopathy mouse model commonly used in pre-clinical studies. Mdx mice ambulated shorter distances than normal controls, a disparity accentuated after mild exercise. An asymmetric pathophysiology in mdx mice was unmasked with exercise, and peak measurements of serum creatine kinase and myoglobinuria were identified. Our data highlights the necessity to consider asymmetric pathology and timing of biomarkers when testing potential therapies for muscular dystrophy. PMID:22154712

  14. Curcumin nanoformulations: a review of pharmaceutical properties and preclinical studies and clinical data related to cancer treatment.

    PubMed

    Naksuriya, Ornchuma; Okonogi, Siriporn; Schiffelers, Raymond M; Hennink, Wim E

    2014-03-01

    Curcumin, a natural yellow phenolic compound, is present in many kinds of herbs, particularly in Curcuma longa Linn. (turmeric). It is a natural antioxidant and has shown many pharmacological activities such as anti-inflammatory, anti-microbial, anti-cancer, and anti-Alzheimer in both preclinical and clinical studies. Moreover, curcumin has hepatoprotective, nephroprotective, cardioprotective, neuroprotective, hypoglycemic, antirheumatic, and antidiabetic activities and it also suppresses thrombosis and protects against myocardial infarction. Particularly, curcumin has demonstrated efficacy as an anticancer agent, but a limiting factor is its extremely low aqueous solubility which hampers its use as therapeutic agent. Therefore, many technologies have been developed and applied to overcome this limitation. In this review, we summarize the recent works on the design and development of nano-sized delivery systems for curcumin, including liposomes, polymeric nanoparticles and micelles, conjugates, peptide carriers, cyclodextrins, solid dispersions, lipid nanoparticles and emulsions. Efficacy studies of curcumin nanoformulations using cancer cell lines and in vivo models as well as up-to-date human clinical trials are also discussed. PMID:24439402

  15. Potential antianxiety activity of Fumaria indica: A preclinical study

    PubMed Central

    Singh, Gireesh K.; Chauhan, Sudhir K.; Rai, Geeta; Chatterjee, Shyam S.; Kumar, Vikas

    2013-01-01

    Background: In the view of diverse CNS modulating properties of Fumaria indica, present study was planned to evaluate its putative anxiolytic activity in behavioural models of rats, followed by elucidation of mechanism of observed activity through biochemical estimations. Materials and Methods: Effects of seven daily 100, 200 and 400 mg/kg oral doses of a Fumaria indica extract (FI) was compared with those of an acute oral dose (5 mg/kg) of lorazepam in a battery of rat models consisting of open-field, elevated plus and zero maze, social interaction, and novelty induced feeding tests. Results: Dose dependant antianxiety effects of FI observed in all tests were qualitatively similar to those of the reference anxiolytic drug. Although FI treatments did not alter the concentrations of noradrenaline and serotonin in hippocampus and hypothalamus, concentrations of both these monoamines were dose dependently elevated in prefrontal cortex of FI treated animals. Flunitrazepam binding in brain frontal cortex was also elevated by the extract. Moreover, higher levels of brain expressions of the cytokines TNF-?, IL-1?, and IL-10 observed in animals with prior experience on elevated plus maze were almost completely reversed by the lowest dose of FI tested in the behavioral models. Conclusion: Taken together, these observations strongly suggest that FI is a functionally novel type of antianxiety agent, and that inhibition of cytokine expressions in the brain could be involved in its mode of action. PMID:23661988

  16. Analgesic and hypnotic activities of Laghupanchamula: A preclinical study

    PubMed Central

    Ghildiyal, Shivani; Gautam, Manish K.; Joshi, Vinod K.; Goel, Raj K.

    2014-01-01

    Background: In Ayurvedic classics, two types of Laghupanchamula -five plant roots (LP) have been mentioned containing four common plants viz. Kantakari, Brihati, Shalaparni, and Prinshniparni and the fifth plant is either Gokshura (LPG) or Eranda (LPE). LP has been documented to have Shothahara (anti-inflammatory), Shulanashka (analgesic), Jvarahara (antipyretic), and Rasayana (rejuvenator) activities. Aim: To evaluate the acute toxicity (in mice), analgesic and hypnotic activity (in rats) of 50% ethanolic extract of LPG (LPGE) and LPE (LPEE). Materials and Methods: LPEG and LPEE were prepared separately by using 50% ethanol following the standard procedures. A graded dose (250, 500 and 1000 mg/kg) response study for both LPEE and LPGE was carried out for analgesic activity against rat tail flick response which indicated 500 mg/kg as the optimal effective analgesic dose. Hence, 500 mg/kg dose of LPEE and LPGE was used for hot plate test and acetic acid induced writhing model in analgesic activity and for evaluation of hypnotic activity. Results: Both the extracts did not produce any acute toxicity in mice at single oral dose of 2.0 g/kg. Both LPGE and LPEE (250, 500, and 1000 mg/kg) showed dose-dependent elevation in pain threshold and peak analgesic effect at 60 min as evidenced by increased latency period in tail-flick method by 25.1-62.4% and 38.2-79.0% respectively. LPGE and LPEE (500 mg/kg) increased reaction time in hot-plate test at peak 60 min analgesic effect by 63.2 and 85.8% and reduction in the number of acetic acid-induced writhes by 55.9 and 65.8% respectively. Both potentiated pentobarbitone-induced hypnosis as indicated by increased duration of sleep in treated rats. Conclusion: The analgesic and hypnotic effects of LP formulations authenticate their uses in Ayurvedic system of Medicine for painful conditions. PMID:25364205

  17. Preclinical Rodent Toxicity Studies for Long Term Use of Ceftriaxone

    PubMed Central

    Ratti, Elena; Berry, James D.; Greenblatt, David J.; Loci, Lorena; Ellrodt, Amy Swartz; Shefner, Jeremy M.; Cudkowicz, Merit E.

    2015-01-01

    A 6-month rodent toxicology and pharmacokinetic (PK) study was performed to provide supportive safety data for long-term use of intravenous ceftriaxone in a clinical trial in patients with amyotrophic lateral sclerosis (ALS). Ceftriaxone was administered by subcutaneous injection at up to 2 g/kg/day to Sprague-Dawley Crl:CD (SD) rats. Ceftriaxone was found to be safe and well tolerated. Specifically, no significant differences in body weight and food consumption were observed between the treatment and control groups. With the exception of in red cell parameters decrease, there were no ceftriaxone-related changes in hematology, coagulation, clinical chemistry and urinalysis parameters. Injection site trauma and associated reversible anemia, likely due to chronic blood loss at the injection site, were all attributable to subcutaneous route of administration. Cecum dilatation and some skin changes were reversible after recovery period, while bile duct dilatation, observed only in a few animals, persisted. Changes in the non-glandular stomach do not have a human correlate. The no-observed-adverse-effect dose level (NOAEL) was 0.5 g/kg/day ceftriaxone in both sexes. Ceftriaxone showed rapid absorption with half-life values ranging between 1 and 1.5 hours. Additionally, there was no evidence of accumulation and a virtually complete elimination by 16 hours after the last dose. Overall there were no toxicologically meaningful drug-related animal findings associated with the long-term administration (6 months) of ceftriaxone. These results support safety of long-term use of ceftriaxone in human clinical trials. PMID:26705515

  18. Pre-clinical efficacy of combined therapy with novel ?-catenin antagonist BC2059 and histone deacetylase inhibitor against AML cells.

    PubMed

    Fiskus, W; Sharma, S; Saha, S; Shah, B; Devaraj, S G T; Sun, B; Horrigan, S; Leveque, C; Zu, Y; Iyer, S; Bhalla, K N

    2015-06-01

    The canonical wingless-type MMTV integration site (WNT)-?-catenin pathway is essential for self-renewal, growth and survival of acute myeloid leukemia (AML) stem/blast progenitor cells (BPCs). Deregulated WNT signaling inhibits degradation of ?-catenin, causing increased nuclear translocation and co-factor activity of ?-catenin with the transcriptional regulator T-cell factor (TCF) 4/lymphoid enhancer factor 1 in AML BPCs. Here, we determined the pre-clinical anti-AML activity of the anthraquinone oxime-analog BC2059 (BC), known to attenuate ?-catenin levels. BC treatment disrupted the binding of ?-catenin with the scaffold protein transducin ?-like 1 and proteasomal degradation and decline in the nuclear levels of ?-catenin. This was associated with reduced transcriptional activity of TCF4 and expression of its target genes, cyclin D1, c-MYC and survivin. BC treatment dose-dependently induced apoptosis of cultured and primary AML BPCs. Treatment with BC also significantly improved the median survival of immune-depleted mice engrafted with either cultured or primary AML BPCs, exhibiting nuclear expression of ?-catenin. Co-treatment with the pan-histone deacetylase inhibitor panobinostat and BC synergistically induced apoptosis of cultured and primary AML BPCs, including those expressing FLT3-ITD, as well as further significantly improved the survival of immune-depleted mice engrafted with primary AML BPCs. These findings underscore the promising pre-clinical activity and warrant further testing of BC against human AML, especially those expressing FLT3-ITD. PMID:25482131

  19. Pre-clinical efficacy of combined therapy with novel ?-catenin antagonist BC2059 and histone deacetylase inhibitor against AML cells

    PubMed Central

    Fiskus, Warren; Sharma, Sunil; Saha, Saikat; Shah, Bhavin; Devaraj, Santhana G. T.; Sun, Baohua; Horrigan, Stephen; Leveque, Christopher; Zu, Youli; Iyer, Swaminathan; Bhalla, Kapil N.

    2014-01-01

    The canonical WNT-?-catenin pathway is essential for self-renewal, growth and survival of AML stem/blast progenitor cells (BPCs). Deregulated WNT signaling inhibits degradation of ?-catenin, causing increased nuclear translocation and co-factor activity of ?-catenin with the transcriptional regulator TCF4/LEF1 in AML BPCs. Here, we determined the pre-clinical anti-AML activity of the anthraquinone oxime-analog BC2059 (BC), known to attenuate ?-catenin levels. BC treatment disrupted the binding of ?-catenin with the scaffold protein TBL1 (transducin ?-like 1) and proteasomal degradation and decline in the nuclear levels of ?-catenin. This was associated with reduced transcriptional activity of TCF4 and expression of its target genes, cyclin D1, c-MYC and survivin. BC treatment dose-dependently induced apoptosis of cultured and primary AML BPCs. Treatment with BC also significantly improved the median survival of immune-depleted mice engrafted with either cultured or primary AML BPCs exhibiting nuclear expression of ?-catenin. Co-treatment with the pan-histone deacetylase inhibitor panobinostat and BC synergistically induced apoptosis of cultured and primary AML BPCs, including those expressing FLT3-ITD, as well as further significantly improved the survival of immune-depleted mice engrafted with primary AML BPCs. These findings underscore the promising pre-clinical activity and warrant further testing of BC against human AML, especially those expressing FLT3-ITD. PMID:25482131

  20. Toxicity of Bothrops sp snake venoms from Ecuador and preclinical assessment of the neutralizing efficacy of a polyspecific antivenom from Costa Rica.

    PubMed

    Laines, Johana; Segura, lvaro; Villalta, Mauren; Herrera, Mara; Vargas, Maringela; Alvarez, Gladys; Gutirrez, Jos Mara; Len, Guillermo

    2014-09-01

    The toxicological profile of the venoms of the snakes Bothrops asper and Bothrops atrox from Ecuador was investigated, together with the venom of a population of B. asper formerly classified as 'Bothrops xanthogrammus'. The three venoms exerted lethal, hemorrhagic, myotoxic, coagulant and defibrinogenating effects, in agreement with the characteristic toxicological profile of Bothrops sp venoms. A polyspecific antivenom (bothropic-crotalic-lachesic) manufactured in Costa Rica was assessed for its preclinical efficacy against the toxic activities of these Ecuadorian venoms. Antivenom was effective in the neutralization of the five activities tested in the three venoms. These observations are in agreement with previous reports on the extensive cross-reactivity and paraspecific neutralization of antivenoms manufactured in Latin America against the venoms of Bothrops sp snakes. PMID:24950051

  1. The failure to detect drug-induced sensory loss in standard preclinical studies.

    PubMed

    Gauvin, David V; Abernathy, Matthew M; Tapp, Rachel L; Yoder, Joshua D; Dalton, Jill A; Baird, Theodore J

    2015-01-01

    Over the years a number of drugs have been approved for human use with limited signs of toxicity noted during preclinical risk assessment study designs but then show adverse events in compliant patients taking the drugs as prescribed within the first few years on the market. Loss or impairments in sensory systems, such as hearing, vision, taste, and smell have been reported to the FDA or have been described in the literature appearing in peer-reviewed scientific journals within the first five years of widespread use. This review highlights the interactive cross-modal compensation within sensory systems that can occur that reduces the likelihood of identifying these losses in less sentient animals used in standard preclinical toxicology and safety protocols. We provide some historical and experimental evidence to substantiate these sensory effects in and highlight the critical importance of detailed training of technicians on basic ethological, species-specific behaviors of all purpose-bred laboratory animals used in these study designs. We propose that the time, effort and cost of training technicians to be better able to identify and document very subtle changes in behavior will serve to increase the likelihood of early detection of biomarkers predictive of drug-induced sensory loss within current standard regulatory preclinical research protocols. PMID:26045062

  2. CEP-7055: a novel, orally active pan inhibitor of vascular endothelial growth factor receptor tyrosine kinases with potent antiangiogenic activity and antitumor efficacy in preclinical models.

    TOXLINE Toxicology Bibliographic Information

    Ruggeri B; Singh J; Gingrich D; Angeles T; Albom M; Yang S; Chang H; Robinson C; Hunter K; Dobrzanski P; Jones-Bolin S; Pritchard S; Aimone L; Klein-Szanto A; Herbert JM; Bono F; Schaeffer P; Casellas P; Bourie B; Pili R; Isaacs J; Ator M; Hudkins R; Vaught J; Mallamo J; Dionne C

    2003-09-15

    Inhibition of the vascular endothelial growth factor VEGF-VEGF receptor (VEGF-R) kinase axes in the tumor angiogenic cascade is a promising therapeutic strategy in oncology. CEP-7055 is the fully synthetic orally active N,N-dimethyl glycine ester of CEP-5214, a C3-(isopropylmethoxy) fused pyrrolocarbazole with potent pan-VEGF-R kinase inhibitory activity. CEP-5214 demonstrates IC(50) values of 18 nM, 12 nM, and 17 nM against human VEGF-R2/KDR kinase, VEGF-R1/FLT-1 kinase, and VEGF-R3/FLT-4 kinase, respectively, in biochemical kinase assays. CEP-5214 inhibited VEGF-stimulated VEGF-R2/KDR autophosphorylation in human umbilical vein endothelial cells (HUVECs) with an IC (50) of approximately 10 nM and demonstrated an equivalent inhibition of murine FLK-1 autophosphorylation in transformed SVR endothelial cells. Evaluation of the antiangiogenic activity of CEP-5214 revealed a dose-related inhibition of microvessel growth ex vivo in rat aortic ring explant cultures and in vitro on HUVEC capillary-tube formation on Matrigel at low nanomolar concentrations. The antiangiogenic activity of CEP-5214 in these bioassays was observed in the absence of apparent cytotoxicity. Single-dose p.o. or s.c. administration of CEP-7055 or CEP-5214 to CD-1 mice at 23.8 mg/kg/dose b.i.d. resulted in a reversible inhibition of VEGF-R2/FLK-1 phosphorylation in murine lung tissues. Administration p.o. of CEP-7055 at 2.57 to 23.8 mg/kg/dose b.i.d. resulted in dose-related reductions in neovascularization in vivo in porcine aortic endothelial cell (PAEC)-VEGF/basic fibroblast growth factor-Matrigel implants in nude mice (maximum, 82% inhibition), significant reductions in granuloma formation (30%) and granuloma vascularity (42%) in a murine chronic inflammation-induced angiogenesis model, and significant and sustained (6 h) inhibition of VEGF-induced plasma extravasation in rats, with an ED(50) of 20 mg/kg/dose. Chronic p.o. administration of CEP-7055 at doses of 11.9 to 23.8 mg/kg/dose b.i.d. resulted in significant inhibition (50-90% maximum inhibition relative to controls) in the growth of a variety of established murine and human s.c. tumor xenografts in nude mice, including A375 melanomas, U251MG and U87MG glioblastomas, CALU-6 lung carcinoma, ASPC-1 pancreatic carcinoma, HT-29 and HCT-116 colon carcinomas, MCF-7 breast carcinomas, and SVR angiosarcomas. Significant antitumor efficacy was observed similarly against orthotopically implanted LNCaP human prostate carcinomas in male nude mice and orthotopically implanted renal carcinoma (RENCA) tumors in BALB/c mice, in terms of a significant reduction in the metastatic score and the extent of pulmonary metastases. These antitumor responses were associated with marked increases in tumor apoptosis, and significant reductions in intratumoral microvessel density (CD34 and Factor VIII staining) of 22-38% relative to controls depending on the specific tumor xenograft. The antitumor efficacy of chronic CEP-7055 administration was independent of initial tumor volume (in the ASPC-1 pancreatic carcinoma model) and reversible on withdrawal of treatment. Chronic p.o. administration of CEP-7055 in preclinical efficacy studies for periods of up to 65 days was well tolerated with no apparent toxicity or significant morbidity. Orally administered CEP-7055 has entered Phase I clinical trials in cancer patients.

  3. Pre-clinical models for oral and periodontal reconstructive therapies.

    PubMed

    Pellegrini, G; Seol, Y J; Gruber, R; Giannobile, W V

    2009-12-01

    The development of new medical formulations (NMF) for reconstructive therapies has considerably improved the available treatment options for individuals requiring periodontal repair or oral implant rehabilitation. Progress in tissue engineering and regenerative medicine modalities strongly depends on validated pre-clinical research. Pre-clinical testing has contributed to the recent approval of NMF such as GEM 21S and INFUSE bone grafts for periodontal and oral regenerative therapies. However, the selection of a suitable pre-clinical model for evaluation of the safety and efficacy of a NMF remains a challenge. This review is designed to serve as a primer to choose the appropriate pre-clinical models for the evaluation of NMF in situations requiring periodontal or oral reconstruction. Here, we summarize commonly used pre-clinical models and provide examples of screening and functional studies of NMF that can be translated into clinical use. PMID:19887682

  4. A Preclinical Study Combining the DNA Repair Inhibitor Dbait with Radiotherapy for the Treatment of Melanoma1

    PubMed Central

    Biau, Julian; Devun, Flavien; Jdey, Wael; Kotula, Ewa; Quanz, Maria; Chautard, Emmanuel; Sayarath, Mano; Sun, Jian-Sheng; Verrelle, Pierre; Dutreix, Marie

    2014-01-01

    Melanomas are highly radioresistant tumors, mainly due to efficient DNA double-strand break (DSB) repair. Dbait (which stands for DNA strand break bait) molecules mimic DSBs and trap DNA repair proteins, thereby inhibiting repair of DNA damage induced by radiation therapy (RT). First, the cytotoxic efficacy of Dbait in combination with RT was evaluated in vitro in SK28 and 501mel human melanoma cell lines. Though the extent of RT-induced damage was not increased by Dbait, it persisted for longer revealing a repair defect. Dbait enhanced RT efficacy independently of RT doses. We further assayed the capacity of DT01 (clinical form of Dbait) to enhance efficacy of palliative RT (10 3 Gy) or radical RT (20 3 Gy), in an SK28 xenografted model. Inhibition of repair of RT-induced DSB by DT01 was revealed by the significant increase of micronuclei in tumors treated with combined treatment. Mice treated with DT01 and RT combination had significantly better tumor growth control and longer survival compared to RT alone with the palliative protocol [tumor growth delay (TGD) by 5.7-fold; median survival: 119 vs 67days] or the radical protocol (TGD by 3.2-fold; median survival: 221 vs 109days). Only animals that received the combined treatment showed complete responses. No additional toxicity was observed in any DT01-treated groups. This preclinical study provides encouraging results for a combination of a new DNA repair inhibitor, DT01, with RT, in the absence of toxicity. A first-in-human phase I study is currently under way in the palliative management of melanoma in-transit metastases (DRIIM trial). PMID:25379020

  5. Translation of Pre-Clinical Studies into Successful Clinical Trials for Alzheimer's Disease: What are the Roadblocks and How Can They Be Overcome?

    PubMed

    Banik, Avijit; Brown, Richard E; Bamburg, James; Lahiri, Debomoy K; Khurana, Dheeraj; Friedland, Robert P; Chen, Wei; Ding, Ying; Mudher, Amritpal; Padjen, Ante L; Mukaetova-Ladinska, Elizabeta; Ihara, Masafumi; Srivastava, Sudhir; Padma Srivastava, M V; Masters, Colin L; Kalaria, Raj N; Anand, Akshay

    2015-01-01

    Preclinical studies are essential for translation to disease treatments and effective use in clinical practice. An undue emphasis on single approaches to Alzheimer's disease (AD) appears to have retarded the pace of translation in the field, and there is much frustration in the public about the lack of an effective treatment. We critically reviewed past literature (1990-2014), analyzed numerous data, and discussed key issues at a consensus conference on Brain Ageing and Dementia to identify and overcome roadblocks in studies intended for translation. We highlight various factors that influence the translation of preclinical research and highlight specific preclinical strategies that have failed to demonstrate efficacy in clinical trials. The field has been hindered by the domination of the amyloid hypothesis in AD pathogenesis while the causative pathways in disease pathology are widely considered to be multifactorial. Understanding the causative events and mechanisms in the pathogenesis are equally important for translation. Greater efforts are necessary to fill in the gaps and overcome a variety of confounds in the generation, study design, testing, and evaluation of animal models and the application to future novel anti-dementia drug trials. A greater variety of potential disease mechanisms must be entertained to enhance progress. PMID:26401762

  6. Evaluation of N-desmethylclozapine as a potential antipsychotic--preclinical studies.

    PubMed

    Natesan, Sridhar; Reckless, Greg E; Barlow, Karen B L; Nobrega, Jos N; Kapur, Shitij

    2007-07-01

    There is growing interest in N-desmethylclozapine (NDMC), the major metabolite of clozapine, as a unique antipsychotic because it acts in vitro as a 5-HT(2) antagonist and as a partial agonist to dopamine D(2) and muscarinic receptors. To explore this, we compared NDMC to a typical (haloperidol), atypical (clozapine), and partial-agonist atypical (aripiprazole) antipsychotic in preclinical models. The comparison was carried out using: brain D(2) and 5-HT(2) receptor occupancy; animal models predictive of antipsychotic efficacy (amphetamine-induced hyperlocomotion (AIL) and conditioned avoidance response (CAR) models); measures predictive of side effects (catalepsy and prolactin elevation); and molecular markers predictive of antipsychotic action (striatal Fos induction). NDMC (10-60 mg/kg/s.c.) showed high 5-HT(2) (64-79%), but minimal D(2) occupancy (<15% at 60 mg/kg) 1 h after administration. In contrast to other antipsychotics, NDMC was not very effective in reducing AIL or CAR and showed minimal induction of Fos in the nucleus accumbens. However, like atypical antipsychotics, it showed no catalepsy, prolactin elevation, and minimal Fos in the dorsolateral striatum. It seems unlikely that NDMC would show efficacy as a stand-alone antipsychotic, however, its freedom from catalepsy and prolactin elevation, and its unique pharmacological profile (muscarinic agonism) may make it feasible to use this drug as an adjunctive treatment to existing antipsychotic regimens. PMID:17164815

  7. Education Predicts Incidence of Preclinical Mobility Disability in Initially High-Functioning Older Women. The Women’s Health and Aging Study II

    PubMed Central

    Gregory, Patricia C.; Xue, Qian-Li; Tian, Jing; Thorpe, Roland J.; Fried, Linda P.

    2011-01-01

    Background. To examine the impact of educational attainment on the incidence of preclinical mobility disability (PCD). Methods. The Women's Health and Aging II Study is a prospective observational cohort study of 436 initially high-functioning community-dwelling women aged 70–79 years at baseline in Baltimore, Maryland. We measured the association of highest attained education level with preclinical mobility disability (PCD) over an 11-year period. PCD is defined as self-reported modification in any of four tasks without reporting difficulty in those tasks. The tasks were walking ½ mile, climbing up steps, doing heavy housework, and getting in/out of bed or chair. Results. Participants with less than 9 years of education were more likely to acquire incident PCD (hazard ratio: 3.1, 95% confidence interval = 1.2–7.7) than their counterparts with more education after adjusting for income, marital status, number of diseases, and high self-efficacy. Conclusions. Lower education level is an independent predictor of incident preclinical mobility disability. This association has important implications for primary and secondary prevention and can be easily assessed in clinical encounters. PMID:21382883

  8. Osteogenic Potential of Dental Mesenchymal Stem Cells in Preclinical Studies: A Systematic Review Using Modified ARRIVE and CONSORT Guidelines

    PubMed Central

    Ramamoorthi, Murali; Bakkar, Mohammed; Jordan, Jack; Tran, Simon D.

    2015-01-01

    Background and Objective. Dental stem cell-based tissue engineered constructs are emerging as a promising alternative to autologous bone transfer for treating bone defects. The purpose of this review is to systematically assess the preclinical in vivo and in vitro studies which have evaluated the efficacy of dental stem cells on bone regeneration. Methods. A literature search was conducted in Ovid Medline, Embase, PubMed, and Web of Science up to October 2014. Implantation of dental stem cells in animal models for evaluating bone regeneration and/or in vitro studies demonstrating osteogenic potential of dental stem cells were included. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were used to ensure the quality of the search. Modified ARRIVE (Animal research: reporting in invivo experiments) and CONSORT (Consolidated reporting of trials) were used to critically analyze the selected studies. Results. From 1914 citations, 207 full-text articles were screened and 137 studies were included in this review. Because of the heterogeneity observed in the studies selected, meta-analysis was not possible. Conclusion. Both in vivo and in vitro studies indicate the potential use of dental stem cells in bone regeneration. However well-designed randomized animal trials are needed before moving into clinical trials. PMID:26106427

  9. Attempted and successful compensation in preclinical and early manifest neurodegeneration - a review of task FMRI studies.

    PubMed

    Scheller, Elisa; Minkova, Lora; Leitner, Mathias; Klöppel, Stefan

    2014-01-01

    Several models of neural compensation in healthy aging have been suggested to explain brain activity that aids to sustain cognitive function. Applying recently suggested criteria of "attempted" and "successful" compensation, we reviewed existing literature on compensatory mechanisms in preclinical Huntington's disease (HD) and amnestic mild cognitive impairment (aMCI). Both disorders constitute early stages of neurodegeneration ideal for examining compensatory mechanisms and developing targeted interventions. We strived to clarify whether compensation criteria derived from healthy aging populations can be applied to early neurodegeneration. To concentrate on the close coupling of cognitive performance and brain activity, we exclusively addressed task fMRI studies. First, we found evidence for parallels in compensatory mechanisms between healthy aging and neurodegenerative disease. Several studies fulfilled criteria of attempted compensation, while reports of successful compensation were largely absent, which made it difficult to conclude on. Second, comparing working memory studies in preclinical HD and aMCI, we identified similar compensatory patterns across neurodegenerative disorders in lateral and medial prefrontal cortex. Such patterns included an inverted U-shaped relationship of neurodegeneration and compensatory activity spanning from preclinical to manifest disease. Due to the lack of studies systematically targeting all criteria of compensation, we propose an exemplary study design, including the manipulation of compensating brain areas by brain stimulation. Furthermore, we delineate the benefits of targeted interventions by non-invasive brain stimulation, as well as of unspecific interventions such as physical activity or cognitive training. Unambiguously detecting compensation in early neurodegenerative disease will help tailor interventions aiming at sustained overall functioning and delayed clinical disease onset. PMID:25324786

  10. The Application of Radiation Therapy to the Pediatric Preclinical Testing Program (PPTP): Results of a Pilot Study in Rhabdomyosarcoma

    PubMed Central

    Sommerfeld, Jim; Bondra, Kathryn; Lu, Lanchun; Leasure, Justin; Nguyen, Phuong; McHugh, Kelsey; Li, Ning; Chronowski, Christopher; Sebastian, Nikhil; Singh, Mamta; Kurmasheva, Raushan; Houghton, Peter; Pelloski, Christopher E.

    2016-01-01

    Background The Pediatric Preclinical Testing Program (PPTP) has been successfully used to determine the efficacy of novel agents against solid tumors by testing them within a mouse-flank in vivo model. To date, radiation therapy has not been applied to this system. We report on the feasibility and biologic outcomes of a pilot study using alveolar and embryonal rhabdomyosarcoma xeno-graft lines. Procedures We developed a high-throughput mouse-flank irradiation device that allows the safe delivery of radiotherapy in clinically relevant doses. For our pilot study, two rhabdomyosarcoma xenograft lines from the PPTP, Rh30 (alveolar) and Rh18 (embryonal) were selected. Using established methods, xenografts were implanted, grown to appropriate volumes, and were subjected to fractionated radiotherapy. Tumor response-rates, growth kinetics, and event-free survival time were measured. Results Once optimized, the rate of acute toxicity requiring early removal from study in 93 mice was only 3%. During the optimization phase, it was observed that the alveolar Rh30 xenograft line demonstrated a significantly greater radiation resistance than embryonal Rh18 in vivo. This finding was validated within the standardized 30 Gy treatment phase, resulting in overall treatment failure rates of 10% versus 60% for the embryonal versus alveolar subtype, respectively. Conclusions Our pilot study demonstrated the feasibility of our device which enables safe, clinically relevant focal radiation delivery to immunocompromised mice. It further recapitulated the expected clinical radiobiology. PMID:22692929

  11. Preclinical development and first-in-human study of ATX-MS-1467 for immunotherapy of MS

    PubMed Central

    Streeter, Heather B.; Rigden, Rachel; Martin, Keith F.; Scolding, Neil J.

    2015-01-01

    Objective: The study was designed to test the efficacy of ATX-MS-1467 in a relevant preclinical model and to assess its safety for the treatment of patients with secondary progressive multiple sclerosis (SPMS). Methods: ATX-MS-1467 was tested for its ability to suppress experimental autoimmune encephalomyelitis (EAE) in the (Ob x DR2)F1 mouse both before and after disease onset. Safety was assessed by clinical assessment, MRI analysis, and the measurement of immune responses to self- and nonself-antigens in patients with SPMS. Results: ATX-MS-1467 displayed a dose-dependent inhibition of EAE and was more effective than glatiramer acetate in the treatment of ongoing disease in humanized mice. A phase 1 open-label dose-escalating study demonstrated that ATX-MS-1467 was safe and well-tolerated in a group of 6 patients with SPMS, up to a dose of 800 g. Conclusions: The results of this study support further development of ATX-MS-1467 in a clinical trial powered to investigate the immunologic and clinical benefits of treatment in relapsing-remitting MS. Classification of evidence: This study provides Class IV evidence that ATX-MS-1467 is safe and tolerated in a group of 6 patients with SPMS. PMID:25798453

  12. Preparation and, in vitro, preclinical and clinical studies of aceclofenac spherical agglomerates.

    PubMed

    Usha, Achutha Nayak; Mutalik, Srinivas; Reddy, Meka Sreenivasa; Ranjith, Averineni Kumar; Kushtagi, Pralhad; Udupa, Nayanabhirama

    2008-10-01

    Aceclofenac agglomerates were prepared by spherical crystallization technique using a three solvent system comprising acetone: dichloromethane (DCM): water (bridging liquid, good solvent and bad solvent, respectively). Hydroxypropyl methylcellulose-50cps (HPMC) in different concentrations was used as hydrophilic polymer. The effect of speed of rotation and amount of bridging liquid on spherical agglomeration were studied. The agglomerates were subjected to various physicochemical evaluations such as practical yield, drug content, particle size, loss on drying, porosity, IR spectroscopy, differential scanning calorimetry, X-ray diffraction studies, relative crystallinity, scanning electron microscopy, micromeritic properties, solubility and dissolution studies. The agglomerates showed improved micromeritic properties as well as dissolution behaviour in comparison to conventional drug crystals. The optimized agglomerates (F-9) showed good sphericity as well as high drug release, and hence they were compressed into tablets by direct compression. The tablets were found within the limits with respect to various physicochemical parameters. The dissolution rate of prepared tablets was better than that of marketed tablet and pure drug. The optimized agglomerates and tablet formulations were found to be stable for 6 months under accelerated conditions. The in vivo studies (preclinical pharmacokinetics, pharmacodynamics and toxicity studies, and clinical pharmacokinetics) of optimized agglomerates were carried out. The results of preclinical studies revealed that the agglomerates provided improved pharmacodynamic and pharmacokinetic profiles of drug besides being nontoxic. The results of pharmacokinetic studies of optimized tablet in human subjects indicated improved pharmacokinetic parameters of drug in comparison with that of marketed tablet. PMID:18606224

  13. Plant-based medicines for anxiety disorders, Part 1: a review of preclinical studies.

    PubMed

    Sarris, Jerome; McIntyre, Erica; Camfield, David A

    2013-03-01

    Research in the area of herbal psychopharmacology has revealed a variety of promising medicines that may provide benefit in the treatment of general anxiety and specific anxiety disorders. However, a comprehensive review of plant-based anxiolytics has been absent to date. This article (part 1) reviews herbal medicines for which only preclinical investigations for anxiolytic activity have been performed. In part 2, we review herbal medicines for which there have been clinical investigations for anxiolytic activity. An open-ended, language-restricted (English) search of MEDLINE (PubMed), CINAHL, Scopus and the Cochrane Library databases was conducted (up to 28 October 2012) using specific search criteria to identify herbal medicines that have been investigated for anxiolytic activity. This search of the literature revealed 1,525 papers, from which 53 herbal medicines were included in the full review (having at least one study using the whole plant extract). Of these plants, 21 had human clinical trial evidence (reviewed in part 2), with another 32 having solely preclinical studies (reviewed here in part 1). Preclinical evidence of anxiolytic activity (without human clinical trials) was found for Albizia julibrissin, Sonchus oleraceus, Uncaria rhynchophylla, Stachys lavandulifolia, Cecropia glazioui, Magnolia spp., Eschscholzia californica, Erythrina spp., Annona spp., Rubus brasiliensis, Apocynum venetum, Nauclea latifolia, Equisetum arvense, Tilia spp., Securidaca longepedunculata, Achillea millefolium, Leea indica, Juncus effusus, Coriandrum sativum, Eurycoma longifolia, Turnera diffusa, Euphorbia hirta, Justicia spp., Crocus sativus, Aloysia polystachya, Albies pindrow, Casimiroa edulis, Davilla rugosa, Gastrodia elata, Sphaerathus indicus, Zizyphus jujuba and Panax ginseng. Common mechanisms of action for the majority of botanicals reviewed primarily involve GABA, either via direct receptor binding or ionic channel or cell membrane modulation; GABA transaminase or glutamic acid decarboxylase inhibition; a range of monoaminergic effects; and potential cannabinoid receptor modulation. Future research should focus on conducting human clinical trials on the plants reviewed with promising anxiolytic activity. PMID:23436255

  14. Exploratory study of factors related to educational scores of first preclinical year medical students.

    PubMed

    Sitticharoon, Chantacha; Srisuma, Sorachai; Kanavitoon, Sawita; Summachiwakij, Sarayut

    2014-03-01

    The relationships among the scores of major subjects taught in the first preclinical year of a Thai medical school, previous academic achievements, and daily life activities are rarely explored. We therefore performed an exploratory study identifying various factors possibly related to the educational scores of these medical students. Questionnaires were sent out to all first preclinical year medical students, with 79.8% being returned (245/307 questionnaires). Positive correlations were revealed between the premedical year grade point average (pre-MD GPA) and anatomy, physiology, and biochemistry scores (R = 0.664, 0.521, and 0.653, respectively, P < 0.001 for all) by Pearson's method. Using multiple linear regression analysis, anatomy scores could be predicted by pre-MD GPA, student satisfaction with anatomy, the percentage of expected reading, monthly earnings, reading after class and near exam time, and duration of sleeping periods near exam time (R = 0.773, R(2) = 0.598, P < 0.001). Physiology scores could be estimated by pre-MD GPA, the percentage of expected reading, monthly earnings, and percentage of those who fell asleep during class and near exam time (R = 0.722, R(2) = 0.521, P < 0.001). Biochemistry scores could be calculated by pre-MD GPA, the percentage of expected reading, motivation to study medicine, student satisfaction with biochemistry, and exam performance expectations (R = 0.794, R(2) = 0.630, P < 0.001). In conclusion, pre-MD GPA and the percentage of expected reading are factors involved in producing good academic results in the first preclinical year. Anatomy and biochemistry, but not physiology, scores are influenced by satisfaction. PMID:24585466

  15. Comparative Plasma Exposure and Lung Distribution of Two Human Use Commercial Azithromycin Formulations Assessed in Murine Model: A Preclinical Study

    PubMed Central

    Rivulgo, Virginia; Sparo, Mnica; Ceci, Mnica; Fumuso, Elida; Confalonieri, Alejandra; Snchez Bruni, Sergio F.

    2013-01-01

    Azithromycin (AZM) therapeutic failure and relapses of patients treated with generic formulations have been observed in clinical practice. The main goal of this research was to compare in a preclinical study the serum exposure and lung tissue concentration of two commercial formulations AZM-based in murine model. The current study involved 264 healthy Balb-C. Mice were divided into two groups (n = 44): animals of Group A (reference formulation -R-) were orally treated with AZM suspension at 10?mg/kg of b.w. Experimental animals of Group B (generic formulation -G-) received identical treatment than Group A with a generic formulation AZM-based. The study was repeated twice as Phase II and III. Serum and lung tissue samples were taken 24?h post treatment. Validated microbiological assay was used to determine the serum pharmacokinetic and lung distribution of AZM. After the pharmacokinetic analysis was observed, a similar serum exposure for both formulations of AZM assayed. In contrast, statistical differences (P < 0.001) were obtained after comparing the concentrations of both formulations in lung tissue, being the values obtained for AUC and Cmax (AZM-R-) +1586 and 122%, respectively, than those obtained for AZM-G- in lung. These differences may indicate large differences on the distribution process of both formulations, which may explain the lack of efficacy/therapeutic failure observed on clinical practice. PMID:24073402

  16. Food for Thought Look Back in Anger – What Clinical Studies Tell Us About Preclinical Work

    PubMed Central

    Hartung, Thomas

    2013-01-01

    Summary Misled by animal studies and basic research? Whenever we take a closer look at the outcome of clinical trials in a field such as, most recently, stroke or septic shock, we see how limited the value of our preclinical models was. For all indications, 95% of drugs that enter clinical trials do not make it to the market, despite all promise of the (animal) models used to develop them. Drug development has started already to decrease its reliance on animal models: In Europe, for example, despite increasing R&D expenditure, animal use by pharmaceutical companies dropped by more than 25% from 2005 to 2008. In vitro studies are likewise limited: questionable cell authenticity, over-passaging, mycoplasma infections, and lack of differentiation as well as non-homeostatic and non-physiologic culture conditions endanger the relevance of these models. The standards of statistics and reporting often are poor, further impairing reliability. Alarming studies from industry show miserable reproducibility of landmark studies. This paper discusses factors contributing to the lack of reproducibility and relevance of pre-clinical research. The conclusion: Publish less but of better quality and do not rely on the face value of animal studies. PMID:23861075

  17. Assessment of an Orofacial Operant Pain Assay as a Preclinical Tool for Evaluating Analgesic Efficacy in Rodents

    PubMed Central

    Ramirez, Harvey E; Queeney, Timothy J; Dunbar, Misha L; Eichner, Michael C; Del Castillo, Dania I; Battles, August H; Neubert, John K

    2015-01-01

    A model system capable of providing clinically relevant analgesic doses with minimal trauma has been elusive in laboratory animal medicine. Our laboratory has developed an orofacial operant pain system that effectively discriminates between nonnoxious and noxious thermal stimuli in rats and mice. Male and female rats (Crl:SD) and mice (Crl:SKR-HRhr) were trained to perform a task (placing their face through an opening and having their cheeks stay in contact with thermodes) to receive a reward (a solution of sweetened condensed milk). Currently accepted doses of buprenorphine were tested by using a crossover design. Pain was induced in both species by sensitizing the depilated skin over both cheeks with capsaicin cream or by creating a surgical incision (rats only) and then allowing the animals to contact a temperature-regulated thermode while obtaining a reward. Optimal antinociceptive doses included 0.05 and 0.1 mg/kg in male mice but only 0.05 mg/kg in female mice. In rats, optimal antinociceptive doses included 0.03 and 0.05 mg/kg for male rats but only 0.03 mg/kg for female rats. The 2 pain-induction models in rats (capsaicin cream and surgical incision) did not differ. Our orofacial operant pain assay can determine clinically relevant analgesic doses for rodents in a preclinical assay. The automated, investigator-independent nature of the assay, in conjunction with its high sensitivity, makes this method an improvement over traditional noninvasive methods, providing better data for developing optimal analgesic recommendations for rats and mice. PMID:26224444

  18. Assessment of an Orofacial Operant Pain Assay as a Preclinical Tool for Evaluating Analgesic Efficacy in Rodents.

    PubMed

    Ramirez, Harvey E; Queeney, Timothy J; Dunbar, Misha L; Eichner, Michael C; Del Castillo, Dania I; Battles, August H; Neubert, John K

    2015-07-01

    A model system capable of providing clinically relevant analgesic doses with minimal trauma has been elusive in laboratory animal medicine. Our laboratory has developed an orofacial operant pain system that effectively discriminates between non-noxious and noxious thermal stimuli in rats and mice. Male and female rats (Crl:SD) and mice (Crl:SKR-HR(hr)) were trained to perform a task (placing their face through an opening and having their cheeks stay in contact with thermodes) to receive a reward (a solution of sweetened condensed milk). Currently accepted doses of buprenorphine were tested by using a crossover design. Pain was induced in both species by sensitizing the depilated skin over both cheeks with capsaicin cream or by creating a surgical incision (rats only) and then allowing the animals to contact a temperature-regulated thermode while obtaining a reward. Optimal antinociceptive doses included 0.05 and 0.1 mg/kg in male mice but only 0.05 mg/kg in female mice. In rats, optimal antinociceptive doses included 0.03 and 0.05 mg/kg for male rats but only 0.03 mg/kg for female rats. The 2 pain-induction models in rats (capsaicin cream and surgical incision) did not differ. Our orofacial operant pain assay can determine clinically relevant analgesic doses for rodents in a preclinical assay. The automated, investigator-independent nature of the assay, in conjunction with its high sensitivity, makes this method an improvement over traditional noninvasive methods, providing better data for developing optimal analgesic recommendations for rats and mice. PMID:26224444

  19. Development of novel combined anticalcification protocols including immunologic modification for prolonged durability of cardiac xenograft: preclinical study using large-animal long-term circulatory models.

    PubMed

    Lim, Hong-Gook; Jeong, Saeromi; Shin, Jun-Seop; Park, Chung-Gyu; Kim, Yong Jin

    2015-01-01

    Cardiac xenografts are conventionally cross-linked with glutaraldehyde (GA) to impart tissue stability, reduce antigenicity, and maintain tissue sterility. However, GA-fixed xenografts are prone to calcification after long-term implantation in humans, because of phospholipids, free aldehyde groups, and residual antigenicity. We evaluated preclinical safety and efficacy using large-animal long-term circulatory models for our novel combined anticalcification protocol including immunological modification, which had been proven effective in small animal experiments. Bovine/porcine xenografts were treated with decellularization, immunological modification with ?-galactosidase, GA fixation with organic solvent, and detoxification with glycine. Valve conduits made of these xenografts were transplanted into the pulmonary root of goats, and hemodynamic, radiological, immunohistopathological, and biochemical results were obtained for 12 months after implantation. Evaluation of echocardiography and cardiac catheterization demonstrated good hemodynamic status and function of the pulmonary xenograft valves. Durability of the xenografts was well preserved without calcification by specimen radiography and immunohistopathological examination. The calcium concentrations of the explanted xenografts were lower than the control xenografts. This preclinical study using large-animal long-term circulatory models demonstrated that our synergistic and simultaneous employment of multiple anticalcification therapies and novel tissue treatments, including immunological modifications, have promising safety and efficacy and should be examined further in future clinical studies. PMID:25303800

  20. Preclinical and clinical phase I studies of a new recombinant Filgrastim (BK0023) in comparison with Neupogen

    PubMed Central

    2014-01-01

    Background Filgrastim or methionyl-granulocyte colony-stimulating factor (Met-G-CSF), is a recombinant therapeutic protein widely used to treat severe neutropenia caused by myelosuppressive drugs in patients with nonmyeloid malignancies. In addition to its role in the regulation of granulopoiesis, treatment with G-CSF is considered the standard approach to mobilize CD34 positive (CD34+) mononuclear cells for reconstituting hemopoietic ability for bone marrow transplantation. An intended biosimilar filgrastim (coded BK0023) was produced in GMP conditions by E.coli fermentation according to an original recombinant process and showed physico-chemical properties and purity profile similar to Neupogen, a commercial preparation of filgrastim. The aim of the present study was to demonstrate the comparability of BK0023 to Neupogen in terms of both in vitro biological activities and in vivo toxicology, pharmacokinetics and pharmacodynamics. Methods Cell proliferation and radioligand binding assays were conducted in NFS-60 cells to compare the biological activity and functional interaction with the G-CSF receptor in vitro, while preclinical in vivo studies, including pharmacokinetics and pharmacodynamics after repeated dose were performed in normal and neutropenic rats. A phase I study was carried out in healthy male volunteers treated by multiple-dose subcutaneous administration of BK0023 and Neupogen to evaluate their pharmacodynamic effects as well as their pharmacokinetic and safety profile and to demonstrate their pharmacodynamic equivalence and pharmacokinetic bioequivalence. Results The results reported in this work demonstrate that BK0023 is comparable in terms of biological activity, efficacy and safety to Neupogen. Conclusions BK0023 has the same pharmacokinetic profile, efficacy and safety as the reference commercial filgrastim Neupogen and therefore could be further developed to become a convenient option to treat neutropenia in oncological patients. Trial registration Trial registration number (TRN): NCT01933971. Date of registration: Sept 6th 2013. PMID:24555723

  1. Preclinical pharmacology, ocular tolerability and ocular hypotensive efficacy of a novel non-peptide bradykinin mimetic small molecule.

    PubMed

    Sharif, Najam A; Li, Linya; Katoli, Parvaneh; Xu, Shouxi; Veltman, James; Li, Byron; Scott, Daniel; Wax, Martin; Gallar, Juana; Acosta, Carmen; Belmonte, Carlos

    2014-11-01

    We sought to characterize the ocular pharmacology, tolerability and intraocular pressure (IOP)-lowering efficacy of FR-190997, a non-peptidic bradykinin (BK) B2-receptor agonist. FR-190997 possessed a relatively high receptor binding affinity (Ki = 27 nM) and a high in vitro potency (EC50 = 18.3 4.4 nM) for inositol-1-phosphate generation via human cloned B2-receptors expressed in host cells with mimimal activity at B1-receptors. It also mobilized intracellular Ca2+ in isolated human trabecular meshwork (h-TM), ciliary muscle (h-CM), and in immortalized non-pigmented ciliary epithelial (h-iNPE) cells (EC50s = 167-384 nM; Emax = 32-86% of BK-induced response). HOE-140, a selective B2-receptor antagonist, potently blocked the latter effects of FR-190997 (e.g., IC50 = 7.3 0.6 nM in h-CM cells). FR-190997 also stimulated the release of prostaglandins (PGs) from h-TM and h-CM cells (EC50s = 60-84 nM; Emax = 29-44% relative to max. BK-induced effects). FR-190997 (0.3-300 ?g t.o.) did not activate cat corneal polymodal nociceptors and did not cause ocular discomfort in Dutch-Belted rabbits, but it was not well tolerated in New Zealand albino rabbits and Hartley guinea pigs. A single topical ocular (t.o.) dose of 1% FR-190997 in Dutch-Belted rabbits and mixed breed cats did not lower IOP. However, FR-190997 efficaciously lowered IOP of conscious ocular hypertensive cynomolgus monkey eyes (e.g., 34.5 7.5% decrease; 6 h post-dose of 30 ?g t.o.; n = 8). Thus, FR-190997 is an unexampled efficacious ocular hypotensive B2-receptor non-peptide BK agonist that activates multiple signaling pathways to cause IOP reduction. PMID:25307520

  2. Onco-retroviral and lentiviral vector-based gene therapy for hemophilia: preclinical studies.

    PubMed

    Van Damme, An; Chuah, Marinee K L; Collen, Dsir; VandenDriessche, Thierry

    2004-04-01

    Hemophilia A and B gene therapy requires long-term and stable expression of coagulation factor VIII (FVIII) or factor IX (FIX), respectively, and would need to compare favorably with protein replacement therapy. Onco-retroviral and lentiviral vectors are attractive vectors for gene therapy of hemophilia. These vectors have the potential for long-term expression because they integrate stably in the target cell genome. Whereas onco-retroviral vectors can only transduce dividing cells, lentiviral vectors can transduce a broad variety of cell types irrespective of cell division. Several preclinical and clinical studies have explored the use of onco-retroviral and, more recently, lentiviral vectors for gene therapy of hemophilia A or B. Both ex vivo and in vivo gene therapy approaches have been evaluated, resulting in therapeutic FVIII or FIX levels in preclinical animal models. Whereas in vivo gene therapy using onco-retroviral or lentiviral vectors often led to long-term FVIII or FIX expression from transduced hepatocytes, ex vivo approaches were generally hampered by either low or transient expression of FVIII or FIX levels in vivo and/or inefficient engraftment. Furthermore, immune responses against the transgene product remain a major issue that must be resolved before the full potential of these vectors eventually can be exploited clinically. Nevertheless, the continued progress in vector design combined with a better understanding of vector biology may ultimately yield more effective gene therapy approaches using these integrating vectors. PMID:15118930

  3. Heparin in malignant glioma: review of preclinical studies and clinical results.

    PubMed

    Schnoor, Rosalie; Maas, Sybren L N; Broekman, Marike L D

    2015-09-01

    Glioblastoma multiforme (GBM) is the most common primary brain tumor that is invariably lethal. Novel treatments are desperately needed. In various cancers, heparin and its low molecular weight derivatives (LMWHs), commonly used for the prevention and treatment of thrombosis, have shown therapeutic potential. Here we systematically review preclinical and clinical studies of heparin and LMWHs as anti-tumor agents in GBM. Even though the number of studies is limited, there is suggestive evidence that heparin may have various effects on GBM. These effects include the inhibition of tumor growth and angiogenesis in vitro and in vivo, and the blocking of uptake of extracellular vesicles. However, heparin can also block the uptake of (potential) anti-tumor agents. Clinical studies suggest a non-significant trend of prolonged survival of LMWH treated GBM patients, with some evidence of increased major bleedings. Heparin mimetics lacking anticoagulant effect are therefore a potential alternative to heparin/LMWH and are discussed as well. PMID:26123362

  4. The Metabotropic Glutamate Receptor 4-Positive Allosteric Modulator VU0364770 Produces Efficacy Alone and in Combination with l-DOPA or an Adenosine 2A Antagonist in Preclinical Rodent Models of Parkinson's Disease

    PubMed Central

    Jones, Carrie K.; Bubser, Michael; Thompson, Analisa D.; Dickerson, Jonathan W.; Turle-Lorenzo, Nathalie; Amalric, Marianne; Blobaum, Anna L.; Bridges, Thomas M.; Morrison, Ryan D.; Jadhav, Satyawan; Engers, Darren W.; Italiano, Kimberly; Bode, Jacob; Daniels, J. Scott; Lindsley, Craig W.; Hopkins, Corey R.; Conn, P. Jeffrey

    2012-01-01

    Parkinson's disease (PD) is a debilitating neurodegenerative disorder associated with severe motor impairments caused by the loss of dopaminergic innervation of the striatum. Previous studies have demonstrated that positive allosteric modulators (PAMs) of metabotropic glutamate receptor 4 (mGlu4), including N-phenyl-7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxamide, can produce antiparkinsonian-like effects in preclinical models of PD. However, these early mGlu4 PAMs exhibited unsuitable physiochemical properties for systemic dosing, requiring intracerebroventricular administration and limiting their broader utility as in vivo tools to further understand the role of mGlu4 in the modulation of basal ganglia function relevant to PD. In the present study, we describe the pharmacologic characterization of a systemically active mGlu4 PAM, N-(3-chlorophenyl)picolinamide (VU0364770), in several rodent PD models. VU0364770 showed efficacy alone or when administered in combination with l-DOPA or an adenosine 2A (A2A) receptor antagonist currently in clinical development (preladenant). When administered alone, VU0364770 exhibited efficacy in reversing haloperidol-induced catalepsy, forelimb asymmetry-induced by unilateral 6-hydroxydopamine (6-OHDA) lesions of the median forebrain bundle, and attentional deficits induced by bilateral 6-OHDA nigrostriatal lesions in rats. In addition, VU0364770 enhanced the efficacy of preladenant to reverse haloperidol-induced catalepsy when given in combination. The effects of VU0364770 to reverse forelimb asymmetry were also potentiated when the compound was coadministered with an inactive dose of l-DOPA, suggesting that mGlu4 PAMs may provide l-DOPA-sparing activity. The present findings provide exciting support for the potential role of selective mGlu4 PAMs as a novel approach for the symptomatic treatment of PD and a possible augmentation strategy with either l-DOPA or A2A antagonists. PMID:22088953

  5. The metabotropic glutamate receptor 4-positive allosteric modulator VU0364770 produces efficacy alone and in combination with L-DOPA or an adenosine 2A antagonist in preclinical rodent models of Parkinson's disease.

    PubMed

    Jones, Carrie K; Bubser, Michael; Thompson, Analisa D; Dickerson, Jonathan W; Turle-Lorenzo, Nathalie; Amalric, Marianne; Blobaum, Anna L; Bridges, Thomas M; Morrison, Ryan D; Jadhav, Satyawan; Engers, Darren W; Italiano, Kimberly; Bode, Jacob; Daniels, J Scott; Lindsley, Craig W; Hopkins, Corey R; Conn, P Jeffrey; Niswender, Colleen M

    2012-02-01

    Parkinson's disease (PD) is a debilitating neurodegenerative disorder associated with severe motor impairments caused by the loss of dopaminergic innervation of the striatum. Previous studies have demonstrated that positive allosteric modulators (PAMs) of metabotropic glutamate receptor 4 (mGlu?), including N-phenyl-7-(hydroxyimino) cyclopropa[b]chromen-1a-carboxamide, can produce antiparkinsonian-like effects in preclinical models of PD. However, these early mGlu? PAMsexhibited unsuitable physiochemical properties for systemic dosing, requiring intracerebroventricular administration and limiting their broader utility as in vivo tools to further understand the role of mGlu? in the modulation of basal ganglia function relevant to PD. In the present study, we describe the pharmacologic characterization of a systemically active mGlu? PAM, N-(3-chlorophenyl)picolinamide (VU0364770), in several rodent PD models. VU0364770 showed efficacy alone or when administered in combination with L-DOPA or an adenosine 2A (A2A) receptor antagonist currently in clinical development (preladenant). When administered alone, VU0364770 exhibited efficacy in reversing haloperidol-induced catalepsy, forelimb asymmetry-induced by unilateral 6-hydroxydopamine (6-OHDA) lesions of the median forebrain bundle, and attentional deficits induced by bilateral 6-OHDA nigrostriatal lesions in rats. In addition, VU0364770 enhanced the efficacy of preladenant to reverse haloperidol-induced catalepsy when given in combination. The effects of VU0364770 to reverse forelimb asymmetry were also potentiated when the compound was coadministered with an inactive dose of L-DOPA, suggesting that mGlu? PAMs may provide L-DOPA-sparing activity. The present findings provide exciting support for the potential role of selective mGlu? PAMs as a novel approach for the symptomatic treatment of PD and a possible augmentation strategy with either L-DOPA or A2A antagonists. PMID:22088953

  6. Enhanced antitumor efficacy of telomerase-selective oncolytic adenoviral agent OBP-401 with docetaxel: preclinical evaluation of chemovirotherapy.

    PubMed

    Fujiwara, Toshiya; Kagawa, Shunsuke; Kishimoto, Hiroyuki; Endo, Yoshikatsu; Hioki, Masayoshi; Ikeda, Yoshihiro; Sakai, Ryo; Urata, Yasuo; Tanaka, Noriaki; Fujiwara, Toshiyoshi

    2006-07-15

    Oncolytic adenoviruses are being developed as novel anticancer therapeutics and currently undergoing clinical trials. We previously demonstrated that telomerase-specific replication-competent adenovirus (Telomelysin: OBP-301), in which the human telomerase reverse transcriptase (hTERT) promoter regulates viral replication, efficiently killed human tumor cells. We further constructed OBP-401 (Telomelysin-GFP) that expresses the green fluorescent protein (GFP) reporter gene under the control of the cytomegalovirus promoter in the E3 region to monitor viral distribution. Here, we examined the feasibility of a single-agent therapy with OBP-401 as well as of combining OBP-401 with chemotherapeutic agents. Infection of OBP-401 alone or followed by the treatment of a chemotherapeutic drug, docetaxel (Taxotere), resulted in a profound in vitro cytotoxicity and GFP expression in various human cancer cell lines originating from different organs (lung, colon, esophagus, stomach, liver and prostate), although the magnitude of antitumor effect varied among the cell types. Other chemotherapeutic drugs such as vinorelbine (Navelbine) and SN38 (the potent active metabolite of irinotecan) combined with OBP-401 also inhibited the growth of human cancer cells. Quantitative real-time PCR analysis demonstrated that docetaxel did not affect viral replication. For in vivo evaluation, nu/nu mice xenografted with H1299 human lung tumor received intratumoral injection of OBP-401 and intraperitoneal administration of docetaxel. Analysis of growth of implanted tumors showed a significant, therapeutic synergism, although OBP-401 alone and docetaxel alone showed modest inhibition of tumor growth. Thus, OBP-401 in combination with docetaxel efficiently enhances the antitumor efficacy both in vitro and in vivo, and the outcome has important implications for tumor-specific oncolytic chemovirotherapies for human cancers. PMID:16477640

  7. Selective Allosteric Inhibition of MMP9 Is Efficacious in Preclinical Models of Ulcerative Colitis and Colorectal Cancer

    PubMed Central

    McCauley, Scott; Kovalenko, Maria; Spangler, Rhyannon; Liu, Chian; Lee, Michael; OSullivan, Christopher; Barry-Hamilton, Vivian; Ghermazien, Haben; Mikels-Vigdal, Amanda; Garcia, Carlos A.; Jorgensen, Brett; Velayo, Arleene C.; Wang, Ruth; Adamkewicz, Joanne I.; Smith, Victoria

    2015-01-01

    Expression of matrix metalloproteinase 9 (MMP9) is elevated in a variety of inflammatory and oncology indications, including ulcerative colitis and colorectal cancer. MMP9 is a downstream effector and an upstream mediator of pathways involved in growth and inflammation, and has long been viewed as a promising therapeutic target. However, previous efforts to target matrix metalloproteinases (MMPs), including MMP9, have utilized broad-spectrum or semi-selective inhibitors. While some of these drugs showed signs of efficacy in patients, all MMP-targeted inhibitors have been hampered by dose-limiting toxicity or insufficient clinical benefit, likely due to their lack of specificity. Here, we show that selective inhibition of MMP9 did not induce musculoskeletal syndrome (a characteristic toxicity of pan-MMP inhibitors) in a rat model, but did reduce disease severity in a dextran sodium sulfate-induced mouse model of ulcerative colitis. We also found that MMP9 inhibition decreased tumor growth and metastases incidence in a surgical orthotopic xenograft model of colorectal carcinoma, and that inhibition of either tumor- or stroma-derived MMP9 was sufficient to reduce primary tumor growth. Collectively, these data suggest that selective MMP9 inhibition is a promising therapeutic strategy for treatment of inflammatory and oncology indications in which MMP9 is upregulated and is associated with disease pathology, such as ulcerative colitis and colorectal cancer. In addition, we report the development of a potent and highly selective allosteric MMP9 inhibitor, the humanized monoclonal antibody GS-5745, which can be used to evaluate the therapeutic potential of MMP9 inhibition in patients. PMID:25961845

  8. Toxicity of L-DOPA coated iron oxide nanoparticles in intraperitoneal delivery setting - preliminary preclinical study.

    PubMed

    Com?nescu, Maria Victoria; Mocanu, Mihaela Andreea; Anghelache, Lauren?iu; Marinescu, Bogdan; Dumitrache, Florian; B?doi, Anca Daniela; Manda, Gina

    2015-01-01

    Iron oxide nanoparticles are promising candidates for theranostics in cancer, that aims to achieve in one-step precise tumor imaging by magnetic resonance, and targeted therapy through surface attached anti-cancer drugs. The aim of this study was to investigate in preclinical setting the biocompatibility of new iron oxide-based nanoparticles that were coated with L-DOPA for improved dispersion in biological media. These nanostructures (NPs) were designed for biomedical applications as contrast agents and/or drug carriers. We investigated the effect exerted in vitro by NPs and L-DOPA on the viability and proliferation of normal mouse L929 fibroblasts. NPs exhibited good biocompatibility against these cells. Moreover, L-DOPA contained in NPs sustained fibroblasts proliferation and/or limited anti-proliferative effects of naked nanoparticles. In the animal study, C57BL/6 mice were injected intraperitoneally with a single dose of NPs (approximately 125 mg/kg body weight). We followed up hematological and histological parameters for one, three and seven days after NPs administration. Results indicated that NPs possibly induced local inflammation and consequent recruitment of peripheral lymphocytes, whilst the decrease of platelet counts may reflect tissue lesions caused by NPs. The histopathological study showed mild to moderate alterations in the hepatocytes, splenic and renal cells, while the brain parenchyma only presented nonspecific congestive changes. Taken altogether, the preclinical study indicated that the new iron oxide nanoparticles coated with L-DOPA were biocompatible against fibroblasts and had a convenient toxicological profile when administered intraperitoneally in a single dose to C57BL/6 mice. Accordingly, the proposed nanostructure is a promising candidate for imaging and treating dispersed peritoneal tumors. PMID:26429160

  9. Systematic reviews and meta-analysis of preclinical studies: why perform them and how to appraise them critically

    PubMed Central

    Sena, Emily S; Currie, Gillian L; McCann, Sarah K; Macleod, Malcolm R; Howells, David W

    2014-01-01

    The use of systematic review and meta-analysis of preclinical studies has become more common, including those of studies describing the modeling of cerebrovascular diseases. Empirical evidence suggests that too many preclinical experiments lack methodological rigor, and this leads to inflated treatment effects. The aim of this review is to describe the concepts of systematic review and meta-analysis and consider how these tools may be used to provide empirical evidence to spur the field to improve the rigor of the conduct and reporting of preclinical research akin to their use in improving the conduct and reporting of randomized controlled trials in clinical research. As with other research domains, systematic reviews are subject to bias. Therefore, we have also suggested guidance for their conduct, reporting, and critical appraisal. PMID:24549183

  10. Resveratrol: A Review of Pre-clinical Studies for Human Cancer Prevention

    PubMed Central

    Athar, Mohammad; Back, Jung Ho; Tang, Xiuwei; Kim, Kwang Ho; Kopelovich, Levy; Bickers, David R.; Kim, Arianna L.

    2007-01-01

    The search for novel and effective cancer chemopreventive agents has led to the identification of various naturally occurring compounds one of which is resveratrol (trans-3, 4′, 5-trihydroxystilbene), a phytoalexin derived from the skin of grapes and other fruits. Resveratrol is known to have potent anti-inflammatory and anti-oxidant effects and to inhibit platelet aggregation and the growth of a variety of cancer cells. Its potential chemopreventive and chemotherapeutic activities have been demonstrated in all three stages of carcinogenesis (initiation, promotion, and progression), in both chemically and UVB-induced skin carcinogenesis in mice, as well as in various murine models of human cancers. Evidence from numerous in vitro and in vivo studies has confirmed its ability to modulate various targets and signaling pathways. This review discusses the current preclinical and mechanistic data available and assesses resveratrol’s anti-cancer effects to support its potential as an anticancer agent in human populations. PMID:17306316

  11. Targeting SRC in glioblastoma tumors and brain metastases: rationale and preclinical studies

    PubMed Central

    Ahluwalia, Manmeet; de Groot, John; Liu, Wei (Michael)

    2011-01-01

    Glioblastoma (GBM) is an extremely aggressive, infiltrative tumor with a poor prognosis. The regulatory approval of bevacizumab for recurrent GBM has confirmed that molecularly targeted agents have potential for GBM treatment. Preclinical data showing that SRC and SRC-family kinases (SFKs) mediate intracellular signaling pathways controlling key biologic/oncogenic processes provide a strong rationale for investigating SRC/SFK inhibitors, eg, dasatinib, in GBM and clinical studies are underway. The activity of these agents against solid tumors suggests that they may also be useful in treating brain metastases. This article reviews the potential for using SRC/SFK inhibitors to treat GBM and brain metastases. Word count =99/100 PMID:20947248

  12. Contribution of large pig for renal ischemia-reperfusion and transplantation studies: the preclinical model.

    PubMed

    Giraud, S; Favreau, F; Chatauret, N; Thuillier, R; Maiga, S; Hauet, T

    2011-01-01

    Animal experimentation is necessary to characterize human diseases and design adequate therapeutic interventions. In renal transplantation research, the limited number of in vitro models involves a crucial role for in vivo models and particularly for the porcine model. Pig and human kidneys are anatomically similar (characterized by multilobular structure in contrast to rodent and dog kidneys unilobular). The human proximity of porcine physiology and immune systems provides a basic knowledge of graft recovery and inflammatory physiopathology through in vivo studies. In addition, pig large body size allows surgical procedures similar to humans, repeated collections of peripheral blood or renal biopsies making pigs ideal for medical training and for the assessment of preclinical technologies. However, its size is also its main drawback implying expensive housing. Nevertheless, pig models are relevant alternatives to primate models, offering promising perspectives with developments of transgenic modulation and marginal donor models facilitating data extrapolation to human conditions. PMID:21403881

  13. Preclinical animal acute toxicity studies of new developed MRI contrast agent based on gadolinium

    NASA Astrophysics Data System (ADS)

    Nam, I. F.; Zhuk, V. V.

    2015-04-01

    Acute toxicity test of new developed MRI contrast agent based on disodium salt of gadopentetic acid complex were carried out on Mus musculus and Sprague Dawley rats according to guidelines of preclinical studies [1]. Groups of six animals each were selected for experiment. Death and clinical symptoms of animals were recorded during 14 days. As a result the maximum tolerated dose (MTD) for female mice is 2.8 mM/kg of body weight, male mice - 1.4 mM/kg, female rats - 2.8 mM/kg, male rats - 5.6 mM/kg of body weight. No Observed Adverse Effect Dose (NOAEL) for female mice is 1.4 mM/kg, male mice - 0.7 mM/kg, male and female rats - 0.7 mM/kg. According to experimental data new developed MRI contrast agent based on Gd-DTPA complex is low-toxic.

  14. Delivery of small molecules for bone regenerative engineering: preclinical studies and potential clinical applications

    PubMed Central

    Laurencin, Cato T.; Ashe, Keshia M.; Henry, Nicole; Kan, Ho Man; Lo, Kevin W-H.

    2014-01-01

    Stimulation of bone regeneration using growth factors is a promising approach for musculoskeletal regenerative engineering. Common limitations with protein growth factors are high manufacturing costs, protein instability, contamination issues, and unwanted immunogenic responses of the host. New strategies for bone regeneration that obviate these problems can have a significant impact on the treatment of skeletal injury and diseases. Over the past decade, a large number of small molecules with the potential of regenerating skeletal tissue have been reported in the literature. Here, we review this literature, paying specific attention to the prospects for small molecule-based bone-regenerative engineering. We also review the preclinical study of small molecules associated with bone regeneration. PMID:24508820

  15. Recent trends in preclinical drug-drug interaction studies of flavonoids?-?Review of case studies, issues and perspectives.

    PubMed

    Srinivas, Nuggehally R

    2015-11-01

    Because of health benefits that are manifested across various disease areas, the consumption of herbal products and/or health supplements containing different kinds of flavonoids has been on the rise. While the drug-drug interaction potential between flavonoids and co-ingested drugs still remain an issue, opportunities exist for the combination of flavonoids with suitable anti-cancer drugs to enhance the bioavailability of anti-cancer drugs and thereby reduce the dose size of the anti-cancer drugs and improve its therapeutic index. In recent years, scores of flavonoids have undergone preclinical investigation with variety of drugs encompassing therapeutic areas such as oncology (etoposide, doxorubicin, paclitaxel, tamoxifen etc.), immunosuppression (cyclosporine) and hypertension (losartan, felodipine, nitrendipine etc.). The review provides examples of the recent trends in the preclinical investigation of 14 flavonoids (morin, quercetin, silibinin, kaempferol etc.) with various co-administered drugs. The relevance of combination of flavonoids with anti-cancer drugs and a framework to help design the in vitro and in vivo preclinical studies to gain better mechanistic insights are discussed. Also, concise discussions on the various physiological factors that contribute for the reduced bioavailability of flavonoids along with the significant challenges in the data interpretation are provided. Copyright 2015 John Wiley & Sons, Ltd. PMID:26343418

  16. Developing a Measurement Tool for Assessing Physiotherapy Students' Self-Efficacy: A Pilot Study

    ERIC Educational Resources Information Center

    Jones, Anne; Sheppard, Lorraine

    2012-01-01

    The aim of this research was to determine if self-efficacy can be correlated with prior academic achievement and whether self-efficacy can be an outcome measure of education. A self-efficacy instrument was developed and administered to physiotherapy students following completion of their pre-clinical theory experience. The questionnaire results

  17. Developing a Measurement Tool for Assessing Physiotherapy Students' Self-Efficacy: A Pilot Study

    ERIC Educational Resources Information Center

    Jones, Anne; Sheppard, Lorraine

    2012-01-01

    The aim of this research was to determine if self-efficacy can be correlated with prior academic achievement and whether self-efficacy can be an outcome measure of education. A self-efficacy instrument was developed and administered to physiotherapy students following completion of their pre-clinical theory experience. The questionnaire results…

  18. Simvastatin Hydroxy Acid Fails to Attain Sufficient Central Nervous System Tumor Exposure to Achieve a Cytotoxic Effect: Results of a Preclinical Cerebral Microdialysis Study.

    PubMed

    Patel, Yogesh T; Jacus, Megan O; Davis, Abigail D; Boulos, Nidal; Turner, David C; Vuppala, Pradeep K; Freeman, Burgess B; Gilbertson, Richard J; Stewart, Clinton F

    2016-04-01

    3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors were potent hits against a mouse ependymoma cell line, but their effectiveness against central nervous system tumors will depend on their ability to cross the blood-brain barrier and attain a sufficient exposure at the tumor. Among 3-hydroxy-3-methylglutaryl coenzyme A inhibitors that had activity in vitro, we prioritized simvastatin (SV) as the lead compound for preclinical pharmacokinetic studies based on its potential for central nervous system penetration as determined from in silico models. Furthermore, we performed systemic plasma disposition and cerebral microdialysis studies of SV (100 mg/kg, p.o.) in a murine model of ependymoma to characterize plasma and tumor extracellular fluid (tECF) pharmacokinetic properties. The murine dosage of SV (100 mg/kg, p.o.) was equivalent to the maximum tolerated dose in patients (7.5 mg/kg, p.o.) based on equivalent plasma exposure of simvastatin acid (SVA) between the two species. SV is rapidly metabolized in murine plasma with 15 times lower exposure compared with human plasma. SVA exposure in tECF was <33.8 ± 11.9 µg/l per hour, whereas the tumor to plasma partition coefficient of SVA was <0.084 ± 0.008. Compared with in vitro washout IC50 values, we did not achieve sufficient exposure of SVA in tECF to suggest tumor growth inhibition; therefore, SV was not carried forward in subsequent preclinical efficacy studies. PMID:26802130

  19. The influence of storage parameters on measurement of survival motor neuron (SMN) protein levels: implications for pre-clinical studies and clinical trials for spinal muscular atrophy.

    PubMed

    Hunter, Gillian; Roche, Sarah L; Somers, Eilidh; Fuller, Heidi R; Gillingwater, Thomas H

    2014-11-01

    Spinal muscular atrophy (SMA) is caused by low levels of survival motor neuron (SMN) protein. A growing number of potential therapeutic strategies for SMA are entering pre-clinical and clinical testing, including gene therapy and antisense oligonucleotide-based approaches. For many such studies SMN protein levels are used as one major readout of treatment efficacy, often necessitating comparisons between samples obtained at different times and/or using different protocols. Whether differences in tissue sampling strategies or storage parameters have an influence on measurable SMN levels remains to be determined. We assessed murine SMN protein immunoreactivity over time and under differing tissue storage conditions. SMN protein levels, measured using sensitive quantitative fluorescent western blotting, declined rapidly over a period of several days following sample collection, especially when protein was extracted immediately and stored at -20°C. Storage of samples at lower temperatures (-80°C), and as intact tissue, led to significantly better preservation of SMN immunoreactivity. However, considerable deterioration in measurable SMN levels occurred, even under optimal storage conditions. These issues need to be taken into consideration when designing and interpreting pre-clinical and clinical SMA studies where SMN protein levels are being measured. PMID:25047670

  20. Mid-stage intervention achieves similar efficacy as conventional early-stage treatment using gene therapy in a pre-clinical model of retinitis pigmentosa

    PubMed Central

    Wert, Katherine J.; Sancho-Pelluz, Javier; Tsang, Stephen H.

    2014-01-01

    Deficiencies in rod-specific cyclic guanosine monophosphate (cGMP) phosphodiesterase-6 (PDE6) are the third most common cause of autosomal recessive retinitis pigmentosa (RP). Previously, viral gene therapy approaches on pre-clinical models with mutations in PDE6 have demonstrated that the photoreceptor cell survival and visual function can be rescued when the gene therapy virus is delivered into the subretinal space before the onset of disease. However, no studies have currently been published that analyze rescue effects after disease onset, a time when human RP patients are diagnosed by a clinician and would receive the treatment. We utilized the AAV2/8(Y733F)-Rho-Pde6? gene therapy virus and injected it into a pre-clinical model of RP with a mutation within the alpha subunit of PDE6: Pde6?D670G. These mice were previously shown to have long-term photoreceptor cell rescue when this gene therapy virus was delivered before the onset of disease. Now, we have determined that subretinal transduction of this rod-specific transgene at post-natal day (P) 21, when approximately half of the photoreceptor cells have undergone degeneration, is more efficient in rescuing cone than rod photoreceptor function long term. Therefore, AAV2/8(Y733F)-Rho-Pde6? is an effective gene therapy treatment that can be utilized in the clinical setting, in human patients who have lost portions of their peripheral visual field and are in the mid-stage of disease when they first present to an eye-care professional. PMID:24101599

  1. Exercise as a Potential Treatment for Drug Abuse: Evidence from Preclinical Studies

    PubMed Central

    Smith, Mark A.; Lynch, Wendy J.

    2012-01-01

    Epidemiological studies reveal that individuals who engage in regular aerobic exercise are less likely to use and abuse illicit drugs. Until recently, very few studies had examined the causal influences that mediate this relationship, and it was not clear whether exercise was effective at reducing substance use and abuse. In the past few years, several preclinical studies have revealed that exercise reduces drug self-administration in laboratory animals. These studies have revealed that exercise produces protective effects in procedures designed to model different transitional phases that occur during the development of, and recover from, a substance use disorder (e.g., acquisition, maintenance, escalation, and relapse/reinstatement of drug use). Moreover, recent studies have revealed several behavioral and neurobiological consequences of exercise that may be responsible for its protective effects in these assays. Collectively, these studies have provided convincing evidence to support the development of exercise-based interventions to reduce compulsive patterns of drug intake in clinical and at-risk populations. PMID:22347866

  2. CCD-camera-based diffuse optical tomography to study ischemic stroke in preclinical rat models

    NASA Astrophysics Data System (ADS)

    Lin, Zi-Jing; Niu, Haijing; Liu, Yueming; Su, Jianzhong; Liu, Hanli

    2011-02-01

    Stroke, due to ischemia or hemorrhage, is the neurological deficit of cerebrovasculature and is the third leading cause of death in the United States. More than 80 percent of stroke patients are ischemic stroke due to blockage of artery in the brain by thrombosis or arterial embolism. Hence, development of an imaging technique to image or monitor the cerebral ischemia and effect of anti-stoke therapy is more than necessary. Near infrared (NIR) optical tomographic technique has a great potential to be utilized as a non-invasive image tool (due to its low cost and portability) to image the embedded abnormal tissue, such as a dysfunctional area caused by ischemia. Moreover, NIR tomographic techniques have been successively demonstrated in the studies of cerebro-vascular hemodynamics and brain injury. As compared to a fiberbased diffuse optical tomographic system, a CCD-camera-based system is more suitable for pre-clinical animal studies due to its simpler setup and lower cost. In this study, we have utilized the CCD-camera-based technique to image the embedded inclusions based on tissue-phantom experimental data. Then, we are able to obtain good reconstructed images by two recently developed algorithms: (1) depth compensation algorithm (DCA) and (2) globally convergent method (GCM). In this study, we will demonstrate the volumetric tomographic reconstructed results taken from tissuephantom; the latter has a great potential to determine and monitor the effect of anti-stroke therapies.

  3. Creative Self-Efficacy: An Intervention Study

    ERIC Educational Resources Information Center

    Mathisen, Gro Ellen; Bronnick, Kolbjorn S.

    2009-01-01

    This study examined the effects of creativity training on creative self-efficacy. We developed a creativity course based on social cognitive theory. The course was conducted in two formats: a five-day course and a condensed one-day course. Samples consisted of students and municipality employees (five-day course), and special education teachers

  4. Creative Self-Efficacy: An Intervention Study

    ERIC Educational Resources Information Center

    Mathisen, Gro Ellen; Bronnick, Kolbjorn S.

    2009-01-01

    This study examined the effects of creativity training on creative self-efficacy. We developed a creativity course based on social cognitive theory. The course was conducted in two formats: a five-day course and a condensed one-day course. Samples consisted of students and municipality employees (five-day course), and special education teachers…

  5. Evaluation of the preclinical efficacy of four antivenoms, distributed in sub-Saharan Africa, to neutralize the venom of the carpet viper, Echis ocellatus, from Mali, Cameroon, and Nigeria.

    PubMed

    Snchez, Laura V; Pla, Davinia; Herrera, Mara; Chippaux, Jean Philippe; Calvete, Juan J; Gutirrez, Jos Mara

    2015-11-01

    Snakebite envenoming causes a heavy toll in sub-Saharan Africa in terms of mortality and sequelae. In the West African savannah, the viperid Echis ocellatus is responsible for the vast majority of bites. In the last decades, several new antivenoms have been introduced for the treatment of these envenomings, although the assessment of their preclinical efficacy against the venom of E. ocellatus has been studied only for some of them. This work analyzed comparatively the ability of four antivenoms (FAV Afrique, EchiTAb G, EchiTAB-Plus-ICP(), and Inoserp Panafricain) to neutralize lethal, hemorrhagic, and in vitro coagulant activities of the venoms of E. ocellatus from Mali, Cameroon, and Nigeria. In addition, an immunoaffinity chromatography antivenomic protocol was used to assess the ability of the four antivenoms to bind to the proteins of these venoms. Results showed that all the antivenoms were effective in the neutralization of the three effects investigated, and were able to immunocapture, completely or partially, the most abundant components in the E. ocellatus venoms from the geographical origins sampled. Our observations also highlighted quantitative differences between antivenoms in their neutralizing and antivenomics profiles, especially regarding neutralization of in vitro coagulant activity, suggesting that different doses of these antivenoms are probably needed for an effective treatment of human envenomings by this species. PMID:26415904

  6. Active and passive immunization strategies based on the SDPM1 peptide demonstrate pre-clinical efficacy in the APPswePSEN1dE9 mouse model for Alzheimer's disease.

    PubMed

    Camboni, Marybeth; Wang, Chiou-Miin; Miranda, Carlos; Yoon, Jung Hae; Xu, Rui; Zygmunt, Deborah; Kaspar, Brian K; Martin, Paul T

    2014-02-01

    Recent clinical and pre-clinical studies suggest that both active and passive immunization strategies targeting A? amyloid may have clinical benefit in Alzheimer's disease. Here, we demonstrate that vaccination of APPswePSEN1dE9 mice with SDPM1, an engineered non-native A? amyloid-specific binding peptide, lowers brain A? amyloid plaque burden and brain A?1-40 and A?1-42 peptide levels, improves cognitive learning and memory in Morris water maze tests and increases the expression of synaptic brain proteins. This was the case in young mice immunized prior to development of significant brain amyloid burden, and in older mice, where brain amyloid was already present. Active immunization was optimized using ALUM as an adjuvant to stimulate production of anti-SDPM1 and anti-A? amyloid antibodies. Intracerebral injection of P4D6, an SDPM1 peptide-mimotope antibody, also lowered brain amyloid plaque burden in APPswePSEN1dE9 mice. Additionally, P4D6 inhibited A? amyloid-mediated toxicity in cultured neuronal cells. The protein sequence of the variable domain within the P4D6 heavy chain was found to mimic a multimer of the SDPM1 peptide motif. These data demonstrate the efficacy of active and passive vaccine strategies to target A? amyloid oligomers using an engineered peptide-mimotope strategy. PMID:24021662

  7. Preclinical Evaluation of Efficacy and Safety of an Improved Lentiviral Vector for the Treatment of β-Thalassemia and Sickle Cell Disease

    PubMed Central

    Negre, Olivier; Bartholomae, Cynthia; Beuzard, Yves; Cavazzana, Marina; Christiansen, Lauryn; Courne, Céline; Deichmann, Annette; Denaro, Maria; de Dreuzy, Edouard; Finer, Mitchell; Fronza, Raffaele; Béatrix, Gillet-Legrand; Joubert, Christophe; Kutner, Robert; Leboulch, Philippe; Maouche, Leïla; Paulard, Anaïs; Pierciey Jr., Francis J.; Rothe, Michael; Ryu, Byoung; Schmidt, Manfred; von Kalle, Christof; Payen, Emmanuel; Veres, Gabor

    2015-01-01

    A previously published clinical trial demonstrated the benefit of autologous CD34+ cells transduced with a self-inactivating lentiviral vector (HPV569) containing an engineered β-globin gene (βA-T87Q globin) in a subject with β-thalassemia major. This vector has been modified to increase transduction efficacy without compromising safety. In vitro analyses indicated that the changes resulted in both increased vector titers (3 to 4 fold) and increased transduction efficacy (2 to 3 fold). An in vivo study in which 58 β-thalassemic mice were transplanted with vector- or mock-transduced syngenic bone marrow cells indicated sustained therapeutic efficacy. Secondary transplantations involving 108 recipients were performed to evaluate long-term safety. The six month study showed no hematological or biochemical toxicity. Integration site (IS) profile revealed an oligo/polyclonal hematopoietic reconstitution in the primary transplants and reduced clonality in secondary transplants. Tumor cells were detected in the secondary transplant mice in all treatment groups (including the control group), without statistical differences in the tumor incidence. Immunohistochemistry and quantitative PCR demonstrated that tumor cells were not derived from transduced donor cells. This comprehensive efficacy and safety data provided the basis for initiating two clinical trials with this second generation vector (BB305) in Europe and in the USA in patients with β-thalassemia major and sickle cell disease. PMID:25429463

  8. HDL and Atherosclerosis Regression: Evidence from Pre-clinical and Clinical Studies

    PubMed Central

    Feig, Jonathan E.; Hewing, Bernd; Smith, Jonathan D.; Hazen, Stanley L.; Fisher, Edward A.

    2014-01-01

    High density lipoprotein particles (HDL) transport, among other molecules, cholesterol (HDL-C). In epidemiologic studies, plasma HDL-C levels have an inverse relationship to the risk of atherosclerotic cardiovascular disease (CVD). It has been assumed that this reflects the protective functions of HDL, which include their ability to promote cholesterol efflux. Yet, a number of recent pharmacological and genetic studies have failed to demonstrate that increased plasma levels of HDL-C resulted in decreased CVD risk, giving rise to a controversy over whether plasma levels of HDL-C reflect HDL function, or that HDL is even as protective as assumed. On balance, the evidence from pre-clinical and (limited) clinical studies show that HDL can promote the regression of atherosclerosis when the levels of functional particles are increased from endogenous or exogenous sources. The data show that regression results from a combination of reduced plaque lipid and macrophage contents, as well as from a reduction in its inflammatory state. While more research will be needed on basic mechanisms and to establish that these changes translate clinically to reduced CVD events, that HDL can regress plaques suggests that the recent trial failures do not eliminate HDL from consideration as an atheroprotective agent, but emphasizes the important distinction between HDL function and plasma levels of HDL-C. PMID:24385513

  9. Preclinical in vivo ADME studies in drug development: a critical review.

    TOXLINE Toxicology Bibliographic Information

    Pellegatti M

    2012-02-01

    INTRODUCTION: The last two decades have brought many fundamental changes to the drug development process. One such change is the importance of preclinical pharmacokinetics, which has become an essential part of early drug discovery. Furthermore, bioanalytical methods have become more sensitive and the identification and quantitation of metabolites can now be carried out on limited amount of biological material. There has also been a change in regulatory expectations, which are now particularly focused on the safety of human metabolites.AREAS COVERED: The focus of this paper is on some 'traditional' in vivo ADME studies: excretion balance, metabolic profile and WBA in the toxicological species. These studies, performed with radiolabeled material, have a long history: and are a regular presence in submission dossiers. This paper reviews their value in the perspective of the contemporary drug development process.EXPERT OPINION: These experiments may sometimes still be relevant to explain toxicological findings or for other special purposes but should not be considered required pieces of the registration dossiers. An appropriate investigation of samples coming from safety evaluation and human Phase I studies and the knowledge generated during the lead optimization phase provide, in most instances, all the DMPK information needed to take decisions in the drug development process.

  10. Preclinical and clinical studies of recombinant poxvirus vaccines for carcinoma therapy.

    PubMed

    Arlen, Philip M; Gulley, James L; Madan, Ravi A; Hodge, James W; Schlom, Jeffrey

    2007-01-01

    Tumor-associated antigens (TAAs) are by definition either weakly immunogenic or functionally nonimmunogenic. Vaccine strategies have been designed to present TAAs to the immune system that may result in far greater activation of T cells than that occurring naturally in the host. These strategies include (1) placing the gene coding for the tumor antigen into poxvirus vectors as a transgene; (2) using diversified prime-and-boost vaccine strategies employing two different types of poxvirus vectors; (3) using T-cell costimulation; and (4) using cytokines, including GM-CSF, as biologic adjuvants. Preclinical studies have been performed comparing the effects on induction of antigen-specific CD8 and CD4 T-cell responses using recombinant poxvirus vectors containing transgenes for a TAA and costimulatory molecules B7-1, ICAM-1, and LFA-3 (designated TRICOM). Antigen-specific T-cell responses were greatest in the group receiving the CEA-TRICOM vaccines and were shown to correlate with survival. We have now completed the first clinical trials with poxvirus vectors containing TRICOM, using the TAAs PSA, CEA, and MUC-1. In addition, clinical studies combining vaccines with radiation therapy, chemotherapy, and second-line hormone therapy have provided preliminary evidence of prolongation of time to disease progression and antigen cascade postvaccination. PMID:18197807

  11. Videotaped Feedback Method to Enhance Learning in Preclinical Operative Dentistry: An Experimental Study.

    PubMed

    Shah, Dipali Yogesh; Dadpe, Ashwini Manish; Kalra, Dheeraj Deepak; Garcha, Vikram P

    2015-12-01

    The aim of this study was to investigate if a videotaped feedback method enhanced teaching and learning outcomes in a preclinical operative laboratory setting for novice learners. In 2013, 60 dental students at a dental school in India were randomly assigned to two groups: control (n=30) and experimental (n=30). The control group prepared a Class II tooth preparation for amalgam after receiving a video demonstration of the exercise. The experimental group received the same video demonstration as the control group, but they also participated in a discussion and analysis of the control groups' videotaped performance and then performed the same exercise. The self-evaluation scores (SS) and examiner evaluation scores (ES) of the two groups were compared using the unpaired t-test. The experimental group also used a five-point Likert scale to rate each item on the feedback form. The means of SS (13.652.43) and ES (14.751.97) of the experimental group were statistically higher than the means of SS (11.552.09) and ES (11.601.82) of the control group. Most students in the experimental group perceived that this technique enhanced their learning experience. Within the limits of this study, the videotaped feedback using both ideal and non-ideal examples enhanced the students' performance. PMID:26632301

  12. Ularitide for the treatment of acute decompensated heart failure: from preclinical to clinical studies

    PubMed Central

    Anker, Stefan D.; Ponikowski, Piotr; Mitrovic, Veselin; Peacock, W. Frank; Filippatos, Gerasimos

    2015-01-01

    The short- and long-term morbidity and mortality in acute heart failure is still unacceptably high. There is an unmet need for new therapy options with new drugs with a new mode of action. One of the drugs currently in clinical testing in Phase III is ularitide, which is the chemically synthesized form of the human natriuretic peptide urodilatin. Urodilatin is produced in humans by differential processing of pro-atrial natriuretic peptide in distal renal tubule cells. Physiologically, urodilatin appears to be the natriuretic peptide involved in sodium homeostasis. Ularitide exerts its pharmacological actions such as vasodilation, diuresis, and natriuresis through the natriuretic peptide receptor/particulate guanylate cyclase/cyclic guanosine monophosphate pathway. In animal models of heart failure as well as Phase I and II clinical studies in heart failure patients, ularitide demonstrated beneficial effects such as symptom relief and vasodilation, while still preserving renal function. Subsequently, the pivotal acute decompensated heart failure (ADHF) Phase III study, called TRUE-AHF, was started with the objectives to evaluate the effects of ularitide infusion on the clinical status and cardiovascular mortality of patients with ADHF compared with placebo. This review summarizes preclinical and clinical data supporting the potential use of ularitide in the treatment of ADHF. PMID:25670819

  13. Ularitide for the treatment of acute decompensated heart failure: from preclinical to clinical studies.

    PubMed

    Anker, Stefan D; Ponikowski, Piotr; Mitrovic, Veselin; Peacock, W Frank; Filippatos, Gerasimos

    2015-03-21

    The short- and long-term morbidity and mortality in acute heart failure is still unacceptably high. There is an unmet need for new therapy options with new drugs with a new mode of action. One of the drugs currently in clinical testing in Phase III is ularitide, which is the chemically synthesized form of the human natriuretic peptide urodilatin. Urodilatin is produced in humans by differential processing of pro-atrial natriuretic peptide in distal renal tubule cells. Physiologically, urodilatin appears to be the natriuretic peptide involved in sodium homeostasis. Ularitide exerts its pharmacological actions such as vasodilation, diuresis, and natriuresis through the natriuretic peptide receptor/particulate guanylate cyclase/cyclic guanosine monophosphate pathway. In animal models of heart failure as well as Phase I and II clinical studies in heart failure patients, ularitide demonstrated beneficial effects such as symptom relief and vasodilation, while still preserving renal function. Subsequently, the pivotal acute decompensated heart failure (ADHF) Phase III study, called TRUE-AHF, was started with the objectives to evaluate the effects of ularitide infusion on the clinical status and cardiovascular mortality of patients with ADHF compared with placebo. This review summarizes preclinical and clinical data supporting the potential use of ularitide in the treatment of ADHF. PMID:25670819

  14. Preclinical endodontic teaching

    PubMed Central

    Narayanaraopeta, Udaya; AlShwaimi, Emad

    2015-01-01

    Objectives: To provide an overview of the general curricula in preclinical endodontic training from 6 established dental schools in Saudi Arabia. Methods: This study was conducted in January 2014 including only schools that had more than 2 groups of student graduates prior to the study. We included 2 dental schools from the Central region, one from Qassim region, one from the Makkah region (west), one from Abha region (south west), and one from the eastern region. An internet-based questionnaire was sent to the course directors of preclinical endodontics department of the 6 schools. The survey comprised 20 questions that examined various aspects of preclinical endodontics. Results: It was demonstrated that a significant number of faculty members had Doctor of Philosophy (PhD) degrees (n=21), Masters degrees (n=15), and Saudi board certifications (n=8). We determined that the faculty to student ratio varied from 2:1 to 8: 1 among the colleges. The participating dental schools were found to teach the Step Back, as well as the Step Down techniques for root canal preparation. Five of the 6 schools implemented the use of nickel titanium rotary instruments. All dental schools predominantly used radiographs as the means of the working length determination. Conclusion: The curriculum for preclinical endodontics in Saudi Arabia is comparable to that followed in most European countries. A more comprehensive survey is needed that would involve more schools to formulate generalized guidelines for preclinical endodontic training in Saudi Arabia. PMID:25630011

  15. A New Mini-External Fixator for Treating Hallux Valgus: A Preclinical, Biomechanical Study.

    PubMed

    Erdil, Mehmet; Ceylan, Hasan Huseyin; Polat, Gokhan; Kara, Deniz; Bozdag, Ergun; Sunbuloglu, Emin

    2016-01-01

    Proximal metatarsal osteotomy is the most effective technique for correcting hallux valgus deformities, especially in metatarsus primus varus. However, these surgeries are technically demanding and prone to complications, such as nonunion, implant failure, and unexpected extension of the osteotomy to the tarsometatarsal joint. In a preclinical study, we evaluated the biomechanical properties of the fixator and compared it with compression screws for treating hallux valgus with a proximal metatarsal osteotomy. Of 18 metatarsal composite bone models proximally osteotomized, 9 were fixed with a headless compression screw and 9 with the mini-external fixator. A dorsal angulation of 10 and displacement of 10mm were defined as the failure threshold values. Construct stiffness and the amount of interfragmentary angulation were calculated at various load cycles. All screw models failed before completing 1000 load cycles. In the fixator group, only 2 of 9 models (22.2%) failed before 1000 cycles, both between the 600th and 700th load cycles. The stability of fixation differed significantly between the groups (p<.001). The stability provided by the mini-external fixator was superior to that of compression screw fixation. Additional testing of the fixator is indicated. PMID:26190777

  16. Autosomal Dominant Alzheimer Disease: A Unique Resource to Study CSF Biomarker Changes in Preclinical AD

    PubMed Central

    Schindler, Suzanne Elizabeth; Fagan, Anne M.

    2015-01-01

    Our understanding of the pathogenesis of Alzheimer disease (AD) has been greatly influenced by investigation of rare families with autosomal dominant mutations that cause early onset AD. Mutations in the genes coding for amyloid precursor protein (APP), presenilin 1 (PSEN-1), and presenilin 2 (PSEN-2) cause over-production of the amyloid-? peptide (A?) leading to early deposition of A? in the brain, which in turn is hypothesized to initiate a cascade of processes, resulting in neuronal death, cognitive decline, and eventual dementia. Studies of cerebrospinal fluid (CSF) from individuals with the common form of AD, late-onset AD (LOAD), have revealed that low CSF A?42 and high CSF tau are associated with AD brain pathology. Herein, we review the literature on CSF biomarkers in autosomal dominant AD (ADAD), which has contributed to a detailed road map of AD pathogenesis, especially during the preclinical period, prior to the appearance of any cognitive symptoms. Current drug trials are also taking advantage of the unique characteristics of ADAD and utilizing CSF biomarkers to accelerate development of effective therapies for AD. PMID:26175713

  17. A Patient-Derived Xenograft Model of Parameningeal Embryonal Rhabdomyosarcoma for Preclinical Studies

    PubMed Central

    Hooper, Jody E.; Cantor, Emma L.; Ehlen, Macgregor S.; Banerjee, Avirup; Malempati, Suman; Stenzel, Peter; Woltjer, Randy L.; Gandour-Edwards, Regina; Goodwin, Neal C.; Yang, Yan; Kaur, Pali; Bult, Carol J.; Airhart, Susan D.; Keller, Charles

    2015-01-01

    Embryonal rhabdomyosarcoma (eRMS) is one of the most common soft tissue sarcomas in children and adolescents. Parameningeal eRMS is a variant that is often more difficult to treat than eRMS occurring at other sites. A 14-year-old female with persistent headaches and rapid weight loss was diagnosed with parameningeal eRMS. She progressed and died despite chemotherapy with vincristine, actinomycin-D, and cyclophosphamide plus 50.4 Gy radiation therapy to the primary tumor site. Tumor specimens were acquired by rapid autopsy and tumor tissue was transplanted into immunodeficient mice to create a patient-derived xenograft (PDX) animal model. As autopsy specimens had an ALK R1181C mutation, PDX tumor bearing animals were treated with the pan-kinase inhibitor lestaurtinib but demonstrated no decrease in tumor growth, suggesting that single agent kinase inhibitor therapy may be insufficient in similar cases. This unique parameningeal eRMS PDX model is publicly available for preclinical study. PMID:26696773

  18. Autosomal Dominant Alzheimer Disease: A Unique Resource to Study CSF Biomarker Changes in Preclinical AD.

    PubMed

    Schindler, Suzanne Elizabeth; Fagan, Anne M

    2015-01-01

    Our understanding of the pathogenesis of Alzheimer disease (AD) has been greatly influenced by investigation of rare families with autosomal dominant mutations that cause early onset AD. Mutations in the genes coding for amyloid precursor protein (APP), presenilin 1 (PSEN-1), and presenilin 2 (PSEN-2) cause over-production of the amyloid-? peptide (A?) leading to early deposition of A? in the brain, which in turn is hypothesized to initiate a cascade of processes, resulting in neuronal death, cognitive decline, and eventual dementia. Studies of cerebrospinal fluid (CSF) from individuals with the common form of AD, late-onset AD (LOAD), have revealed that low CSF A?42 and high CSF tau are associated with AD brain pathology. Herein, we review the literature on CSF biomarkers in autosomal dominant AD (ADAD), which has contributed to a detailed road map of AD pathogenesis, especially during the preclinical period, prior to the appearance of any cognitive symptoms. Current drug trials are also taking advantage of the unique characteristics of ADAD and utilizing CSF biomarkers to accelerate development of effective therapies for AD. PMID:26175713

  19. Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) in Preclinical Studies of Antivascular Treatments

    PubMed Central

    Nielsen, Thomas; Wittenborn, Thomas; Horsman, Michael R.

    2012-01-01

    Antivascular treatments can either be antiangiogenic or targeting established tumour vasculature. These treatments affect the tumour microvasculature and microenvironment but may not change clinical measures like tumour volume and growth. In research on antivascular treatments, information on the tumour vasculature is therefore essential. Preclinical research is often used for optimization of antivascular drugs alone or in combined treatments. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is an in vivo imaging method providing vascular information, which has become an important tool in both preclinical and clinical research. This review discusses common DCE-MRI imaging protocols and analysis methods and provides an overview of preclinical research on antivascular treatments utilizing DCE-MRI. PMID:24300371

  20. Preclinical Alzheimer’s disease and its outcome: a longitudinal cohort study

    PubMed Central

    Vos, Stephanie J.B.; Xiong, Chengjie; Visser, Pieter Jelle; Jasielec, Mateusz S.; Hassenstab, Jason; Grant, Elizabeth A.; Cairns, Nigel J.; Morris, John C.; Holtzman, David M.; Fagan, Anne M.

    2013-01-01

    Background New research criteria for preclinical Alzheimer’s disease (AD)have been proposed by the National Institute on Aging and Alzheimer’s Association. They include stages for cognitively normal individuals with abnormal amyloid markers (stage 1), abnormal amyloid and injury markers (stage 2) and abnormal amyloid and injury markers and subtle cognitive changes (stage 3). We investigated the occurrence and long-term outcome of these stages. Methods Cerebrospinal fluidamyloid-β1–42 and tau levels and a memory composite score were used to classify 311 cognitively normal(Clinical Dementia Rating [CDR]=0) research participants ≥65 years as normal (both markers normal), preclinical AD stage 1–3, or Suspected Non-Alzheimer Pathophysiology (SNAP, abnormal injury marker without abnormal amyloid marker). Outcome measures were progression to CDR≥0·5 symptomatic AD and mortality up to 15 years after baseline (average=4 years). Findings 129 (41·5%) of participants were normal, 47 (15%)were in stage 1, 36 (12%) in stage 2, 13 (4%)in stage 3, 72 (23%) had SNAP, and 14 (4·5%) remained unclassified. The proportion of preclinical AD (stage 1–3) in our cohort was higher in individuals older than 72 years and in APOE-ε4 carriers. The 5-year progression rate to CDR≥0·5 symptomatic AD was 2% for normal participants, 11% for stage 1, 26% for stage 2, 56% for stage 3, and 5% for SNAP. Compared with normal individuals, participants with preclinical AD had an increased risk of death (HR=6·2, p=0·0396). Interpretation Preclinical AD is common in cognitively normal elderly and strongly associated with future cognitive decline and mortality. Preclinical AD thus should be an important target for therapeutic interventions. PMID:24012374

  1. Designing More Efficient Preclinical Experiments: A Simulation Study in Chemotherapy-Induced Myelosupression

    PubMed Central

    Martin, Emma C.; Aarons, Leon; Yates, James W. T.

    2016-01-01

    A new more efficient preclinical study design (referred to as a compact design) is proposed that removes the need for satellite animals for the collection of toxicokinetic (TK) data by sampling from the main study animals, taking no more than one sample in 24 h to build up a full profile over the course of the study. The compact design’s performance was tested with a simulation study, using an example of chemotherapy-induced myelosupression in rats. Data sets were simulated from a model based on available data, following both the compact design and a traditional design using satellite animals, with 100 studies being simulated for each. The effect of the compact design on parameter and variance estimates for the TK and neutrophil models were investigated, as well as the potential effect of interoccasion variability (IOV). The compact design performed equally as well as the traditional design, and had little impact on parameter or variation estimates, indicating that it would be a suitable alternative to traditional satellite designs while reducing the number of animals required. When IOV was present but not accounted for during the TK analysis some parameter estimates were biased and interindividual variation and residual errors inflated; this was reduced by allowing for IOV in the analysis. Using the compact design removes the need for a satellite group, reducing the number of animals required, without affecting the ability to model the data. If large IOV is suspected, caution should be exercised to avoid parameter estimation bias, and inflation of variability and residual error. PMID:26678701

  2. Designing More Efficient Preclinical Experiments: A Simulation Study in Chemotherapy-Induced Myelosupression.

    PubMed

    Martin, Emma C; Aarons, Leon; Yates, James W T

    2016-03-01

    A new more efficient preclinical study design (referred to as a compact design) is proposed that removes the need for satellite animals for the collection of toxicokinetic (TK) data by sampling from the main study animals, taking no more than one sample in 24?h to build up a full profile over the course of the study. The compact design's performance was tested with a simulation study, using an example of chemotherapy-induced myelosupression in rats. Data sets were simulated from a model based on available data, following both the compact design and a traditional design using satellite animals, with 100 studies being simulated for each. The effect of the compact design on parameter and variance estimates for the TK and neutrophil models were investigated, as well as the potential effect of interoccasion variability (IOV). The compact design performed equally as well as the traditional design, and had little impact on parameter or variation estimates, indicating that it would be a suitable alternative to traditional satellite designs while reducing the number of animals required. When IOV was present but not accounted for during the TK analysis some parameter estimates were biased and interindividual variation and residual errors inflated; this was reduced by allowing for IOV in the analysis. Using the compact design removes the need for a satellite group, reducing the number of animals required, without affecting the ability to model the data. If large IOV is suspected, caution should be exercised to avoid parameter estimation bias, and inflation of variability and residual error. PMID:26678701

  3. Timing of Decompressive Surgery of Spinal Cord after Traumatic Spinal Cord Injury: An Evidence-Based Examination of Pre-Clinical and Clinical Studies

    PubMed Central

    Furlan, Julio C.; Noonan, Vanessa; Cadotte, David W.

    2011-01-01

    Abstract While the recommendations for spine surgery in specific cases of acute traumatic spinal cord injury (SCI) are well recognized, there is considerable uncertainty regarding the role of the timing of surgical decompression of the spinal cord in the management of patients with SCI. Given this, we sought to critically review the literature regarding the pre-clinical and clinical evidence on the potential impact of timing of surgical decompression of the spinal cord on outcomes after traumatic SCI. The primary literature search was performed using MEDLINE, CINAHL, EMBASE, and Cochrane databases. A secondary search strategy incorporated articles referenced in prior meta-analyses and systematic and nonsystematic review articles. Two reviewers independently assessed every study with regard to eligibility, level of evidence, and study quality. Of 198 abstracts of pre-clinical studies, 19 experimental studies using animal SCI models fulfilled our inclusion and exclusion criteria. Despite some discrepancies in the results of those pre-clinical studies, there is evidence for a biological rationale to support early decompression of the spinal cord. Of 153 abstracts of clinical studies, 22 fulfilled the inclusion and exclusion criteria. While the vast majority of the clinical studies were level-4 evidence, there were two studies of level-2b evidence. The quality assessment scores varied from 7 to 25 with a mean value of 12.41. While 2 of 22 clinical studies assessed feasibility and safety, 20 clinical studies examined efficacy of early surgical intervention to stabilize and align the spine and to decompress the spinal cord; the most common definitions of early operation used 24 and 72?h after SCI as timelines. A number of studies indicated that patients who undergo early surgical decompression can have similar outcomes to patients who received a delayed decompressive operation. However, there is evidence to suggest that early surgical intervention is safe and feasible and that it can improve clinical and neurological outcomes and reduce health care costs. Based on the current clinical evidence using a Delphi process, an expert panel recommended that early surgical intervention should be considered in all patients from 8 to 24?h following acute traumatic SCI. PMID:20001726

  4. Nanomedicines for cancer therapy: state-of-the-art and limitations to pre-clinical studies that hinder future developments

    NASA Astrophysics Data System (ADS)

    Dawidczyk, Charlene; Russell, Luisa; Searson, Peter

    2014-08-01

    The ability to efficiently deliver a drug or gene to a tumor site is dependent on a wide range of factors including circulation time, interactions with the mononuclear phagocyte system, extravasation from circulation at the tumor site, targeting strategy, release from the delivery vehicle, and uptake in cancer cells. Nanotechnology provides the possibility of creating delivery systems where the design constraints are decoupled, allowing new approaches for reducing the unwanted side effects of systemic delivery, increasing tumor accumulation, and improving efficacy. The physico-chemical properties of nanoparticle-based delivery platforms introduce additional complexity associated with pharmacokinetics and tumor accumulation. To assess the impact of nanoparticle-based delivery systems, we first review the design strategies and pharmacokinetics of FDA-approved nanomedicines. Next we review nanomedicines under development, summarizing the range of nanoparticle platforms, strategies for targeting, and pharmacokinetics. We show how the lack of uniformity in preclinical trials prevents systematic comparison and hence limits advances in the field.

  5. COMPARATIVE EFFECTIVENESS AND SAFETY OF IMAGE GUIDANCE SYSTEMS IN NEUROSURGERY: A PRECLINICAL RANDOMIZED STUDY

    PubMed Central

    Marcus, Hani J; Pratt, Philip; Hughes-Hallett, Archie; Cundy, Thomas P; Marcus, Adam P; Yang, Guang-Zhong; Darzi, Ara; Nandi, Dipankar

    2015-01-01

    Object Over the last decade image guidance systems have been widely adopted in neurosurgery. Nonetheless, the evidence supporting the use of these systems in surgery remains limited. The aim of this study was to compare simultaneously the effectiveness and safety of various image guidance systems against standard surgery. Methods In this preclinical randomized study 50 novice surgeons were allocated to: (1) no image guidance, (2) triplanar display, (3) always-on solid overlay, (4) always-on wire mesh overlay, and (5) on-demand inverse realism overlay. Each participant was asked to identify a basilar tip aneurysm in a validated model head. The primary outcomes were time to task completion (seconds), and tool path length (millimeters). The secondary outcomes were recognition of an unexpected finding (a surgical clip), and subjective depth perception using a Likert scale. Results The time to task completion and tool path length were significantly lower when utilizing any form of image guidance compared to no image guidance (p < 0·001 and p = 0·003, respectively). The tool path distance was also lower in groups utilizing augmented reality compared to triplanar display (p = 0·010). Always-on solid overlay resulted in the greatest inattentional blindness (20% recognition of unexpected finding). Wire mesh and on-demand overlays mitigated but did not negate inattentional blindness, and were comparable to triplanar display (40% recognition of unexpected finding in all groups). Wire mesh and inverse realism overlays also resulted in better subjective depth perception than always-on solid overlay (p = 0·031 and p = 0·008, respectively). Conclusions New augmented reality platforms may improve performance in less experienced surgeons. However, all image display modalities, including existing triplanar display, carry a risk of inattentional blindness. PMID:25909567

  6. Executive Function Changes before Memory in Preclinical Alzheimer’s Pathology: A Prospective, Cross-Sectional, Case Control Study

    PubMed Central

    Harrington, Michael G.; Chiang, Jiarong; Pogoda, Janice M.; Gomez, Megan; Thomas, Kris; Marion, Sarah DeBoard; Miller, Karen J.; Siddarth, Prabha; Yi, Xinyao; Zhou, Feimeng; Lee, Sherri; Arakaki, Xianghong; Cowan, Robert P.; Tran, Thao; Charleswell, Cherise; Ross, Brian D.; Fonteh, Alfred N.

    2013-01-01

    Background Early treatment of Alzheimer’s disease may reduce its devastating effects. By focusing research on asymptomatic individuals with Alzheimer’s disease pathology (the preclinical stage), earlier indicators of disease may be discovered. Decreasing cerebrospinal fluid beta-amyloid42 is the first indicator of preclinical disorder, but it is not known which pathology causes the first clinical effects. Our hypothesis is that neuropsychological changes within the normal range will help to predict preclinical disease and locate early pathology. Methods and Findings We recruited adults with probable Alzheimer’s disease or asymptomatic cognitively healthy adults, classified after medical and neuropsychological examination. By logistic regression, we derived a cutoff for the cerebrospinal fluid beta amyloid42/tau ratios that correctly classified 85% of those with Alzheimer’s disease. We separated the asymptomatic group into those with (n = 34; preclinical Alzheimer’s disease) and without (n = 36; controls) abnormal beta amyloid42/tau ratios; these subgroups had similar distributions of age, gender, education, medications, apolipoprotein-ε genotype, vascular risk factors, and magnetic resonance imaging features of small vessel disease. Multivariable analysis of neuropsychological data revealed that only Stroop Interference (response inhibition) independently predicted preclinical pathology (OR = 0.13, 95% CI = 0.04–0.42). Lack of longitudinal and post-mortem data, older age, and small population size are limitations of this study. Conclusions Our data suggest that clinical effects from early amyloid pathophysiology precede those from hippocampal intraneuronal neurofibrillary pathology. Altered cerebrospinal fluid beta amyloid42 with decreased executive performance before memory impairment matches the deposits of extracellular amyloid that appear in the basal isocortex first, and only later involve the hippocampus. We propose that Stroop Interference may be an additional important screen for early pathology and useful to monitor treatment of preclinical Alzheimer’s disease; measures of executive and memory functions in a longitudinal design will be necessary to more fully evaluate this approach. PMID:24260210

  7. Correlates of preclinical cardiovascular disease in Indigenous and Non-Indigenous Australians: a case control study

    PubMed Central

    Haluska, Brian A; Chan, Lionel; Jeffriess, Leanne; Shaw, A Andrew; Shaw, Joanne; Marwick, Thomas H

    2008-01-01

    Background The high frequency of premature death from cardiovascular disease in indigenous Australians is often attributed to the high prevalence of risk factors, especially type II diabetes mellitus (DM). We evaluated the relationship of ethnicity to atherosclerotic burden, as evidenced by carotid intima-media thickness (IMT), independent of risk factor status. Methods We studied 227 subjects (147 men; 50 13 y): 119 indigenous subjects with (IDM, n = 54), and without DM (InDM, n = 65), 108 Caucasian subjects with (CDM, n = 52), and without DM (CnDM, n = 56). IMT was measured according to standard methods and compared with clinical data and cardiovascular risk factors. Results In subjects both with and without DM, IMT was significantly greater in indigenous subjects. There were no significant differences in gender, body mass index (BMI), systolic blood pressure (SBP), or diastolic blood pressure (DBP) between any of the groups, and subjects with DM showed no difference in plasma HbA1c. Cardiovascular risk factors were significantly more prevalent in indigenous subjects. Nonetheless, ethnicity (? = -0.34; p < 0.0001), age (? = 0.48; p < 0.0001), and smoking (? = 0.13; p < 0.007) were independent predictors of IMT in multiple linear regression models. Conclusion Ethnicity appears to be an independent correlate of preclinical cardiovascular disease, even after correction for the high prevalence of cardiovascular risk factors in indigenous Australians. Standard approaches to control currently known risk factors are vital to reduce the burden of cardiovascular disease, but in themselves may be insufficient to fully address the high prevalence in this population. PMID:18627637

  8. Irinotecan delivery by microbubble-assisted ultrasound - A pilot preclinical study

    NASA Astrophysics Data System (ADS)

    Escoffre, Jean-Michel; Novell, Anthony; Serrire, Sophie; Bouakaz, Ayache

    2012-11-01

    Irinotecan is conventionally used for the treatment of colorectal cancer. However, its administration is associated with severe side effects. Targeted drug delivery using ultrasound (US) combined with microbubbles offers new opportunities to increase the therapeutic effectiveness of antitumor treatment and to reduce toxic exposure to healthy tissues. The objective of this study is to investigate the safety and efficacy of in-vivo delivery of irinotecan by microbubble-assisted US in human glioblastoma model (U-87 MG). In order to validate the potential of this new method in-vivo, subcutaneous tumors were implanted in the flank of nude mouse and treated when they reached a volume of 100 mm3. In the first study, the measured volumes with caliper and anatomic ultrasound imaging were compared for the monitoring and the quantification of tumor growth during 27 days. Ultrasound imaging measurements were positively correlated to caliper measurements. The tumor treatment consisted of an i.v. injection of irinotecan (20 mg/kg) followed one hour later by i.v. administration of MM1 microbubble and an US insonation using a single-element transducer operating at 1MHz (400 kPa, 10 kHz PRF 40% DC, 3 min). The therapeutic efficacy was evaluated for 39 days by measuring the tumor volume before and after treatment using a caliper and based on ultrasound images using an 18 MHz probe (Vevo 2100). Our results showed that anatomical ultrasound imaging was as efficient as caliper for the monitoring and the quantification of tumor growth. Moreover, irinotecan delivery by sonoporation induced a significant decrease of glioblastoma tumor volume and an increase of tumor-doubling time compared to the tumor treated by irinotecan alone. In conclusion, this novel therapeutic approach has promising features since it can be used to reduce the injected drug dose and to achieve a better therapeutic efficacy.

  9. Pharmacological treatment of idiopathic pulmonary fibrosis – preclinical and clinical studies of pirfenidone, nintedanib, and N-acetylcysteine

    PubMed Central

    Myllärniemi, Marjukka; Kaarteenaho, Riitta

    2015-01-01

    Three recent clinical trials on the pharmacologic treatment of idiopathic pulmonary fibrosis (IPF) mark a new chapter in the management of patients suffering from this very severe fibrotic lung disease. This review article summarizes the published investigations on the preclinical studies of three novel IPF drugs, namely pirfenidone, nintedanib, and N-acetylcysteine (NAC). In addition, the study protocols, differences, and the main findings in the recent clinical trials of these pharmacological treatments are reviewed. The strategy for drug development and the timeline from the discovery to the clinical use have been very different in these regimens. Pirfenidone was discovered in 1976 but only recently received approval in most countries, and even now its exact mechanism of action is unknown. On the contrary, nintedanib (BIBF1120) was identified in large drug screening tests as a very specific inhibitor of certain tyrosine kinases, but no published data on preclinical tests existed until 2014. NAC, a mucolytic drug with an antioxidant mechanism of action was claimed to possess distinct antifibrotic properties in several experimental models but proved to be ineffective in a recent randomized placebo-controlled trial. At present, no curative treatment is available for IPF. A better understanding of the molecular mechanisms of IPF as well as relevant preclinical tests including animal models and in vitro experiments on human lung cells are needed to promote the development of therapeutic drugs. PMID:26557253

  10. In question: the scientific value of preclinical safety pharmacology and toxicology studies with cell-based therapies

    PubMed Central

    Broichhausen, Christiane; Riquelme, Paloma; Ahrens, Norbert; Wege, Anja K; Koehl, Gudrun E; Schlitt, Hans J; Banas, Bernhard; Fändrich, Fred; Geissler, Edward K; Hutchinson, James A

    2014-01-01

    A new cell-based medicinal product containing human regulatory macrophages, known as Mreg_UKR, has been developed and conforms to expectations of a therapeutic drug. Here, Mreg_UKR was subjected to pharmacokinetic, safety pharmacology, and toxicological testing, which identified no adverse reactions. These results would normally be interpreted as evidence of the probable clinical safety of Mreg_UKR; however, we contend that, owing to their uncertain biological relevance, our data do not fully support this conclusion. This leads us to question whether there is adequate scientific justification for preclinical safety testing of similar novel cell-based medicinal products using animal models. In earlier work, two patients were treated with regulatory macrophages prior to kidney transplantation. In our opinion, the absence of acute or chronic adverse effects in these cases is the most convincing available evidence of the likely safety of Mreg_UKR in future recipients. On this basis, we consider that safety information from previous clinical investigations of related cell products should carry greater weight than preclinical data when evaluating the safety profile of novel cell-based medicinal products. By extension, we argue that omitting extensive preclinical safety studies before conducting small-scale exploratory clinical investigations of novel cell-based medicinal products data may be justifiable in some instances. PMID:26015968

  11. Trajectories of memory decline in preclinical Alzheimer's disease: results from the Australian Imaging, Biomarkers and Lifestyle Flagship Study of ageing.

    PubMed

    Pietrzak, Robert H; Lim, Yen Ying; Ames, David; Harrington, Karra; Restrepo, Carolina; Martins, Ralph N; Rembach, Alan; Laws, Simon M; Masters, Colin L; Villemagne, Victor L; Rowe, Christopher C; Maruff, Paul

    2015-03-01

    Memory changes in preclinical Alzheimer's disease (AD) are often characterized by heterogenous trajectories. However, data regarding the nature and determinants of predominant trajectories of memory changes in preclinical AD are lacking. We analyzed data from 333 cognitively healthy older adults who participated in a multicenter prospective cohort study with baseline and 18-, 36-, and 54-month follow-up assessments. Latent growth mixture modeling revealed 3 predominant trajectories of memory change: a below average, subtly declining memory trajectory (30.9%); a below average, rapidly declining memory trajectory (3.6%); and an above average, stable memory trajectory (65.5%). Compared with the stable memory trajectory, high Αβ (relative risk ratio [RRR] = 2.1), and lower Mini-Mental State Examination (RRR = 0.6) and full-scale IQ (RRR = 0.9) scores were independently associated with the subtly declining memory trajectory; and high Αβ (RRR = 8.3), APOE ε4 carriage (RRR = 6.1), and greater subjective memory impairment (RRR = 1.2) were independently associated with the rapidly declining memory trajectory. Compared with the subtly declining memory trajectory group, APOE ε4 carriage (RRR = 8.4), and subjective memory complaints (RRR = 1.2) were associated with a rapidly declining memory trajectory. These results suggest that the preclinical phase of AD may be characterized by 2 predominant trajectories of memory decline that have common (e.g., high Αβ) and unique (e.g., APOE ε4 genotype) determinants. PMID:25585532

  12. Combination treatment with hypoxia-activated prodrug evofosfamide (TH-302) and mTOR inhibitors results in enhanced antitumor efficacy in preclinical renal cell carcinoma models

    PubMed Central

    Sun, Jessica D; Ahluwalia, Dharmendra; Liu, Qian; Li, Wenwu; Wang, Yan; Meng, Fanying; Bhupathi, Deepthi; Matteucci, Mark D; Hart, Charles P

    2015-01-01

    Tumors often consist of hypoxic regions which are resistant to chemo- and radiotherapy. Evofosfamide (also known as TH-302), a 2-nitroimidazole triggered hypoxia-activated prodrug, preferentially releases the DNA cross-linker bromo-isophosphoramide mustard in hypoxic cells. The intracellular kinase mTOR plays a key role in multiple pathways which are important in cancer progression. Here we investigated the enhanced efficacy profile and possible mechanisms of evofosfamide in combination with mTOR inhibitor (mTORi) everolimus or temsirolimus in renal cell carcinoma (RCC) xenograft models. The antitumor activities of the mTORi everolimus or temsirolimus alone, evofosfamide alone, or the combination were investigated in the 786-O and Caki-1 RCC cells in vitro and in vivo xenograft models. Two schedules were tested in which evofosfamide was started on the same day as the mTORi or 1 week after. Combination mechanisms were investigated by measuring a panel of pharmacodynamic biomarkers by immunohistochemistry. Antitumor efficacy in both RCC xenograft models was enhanced by the combination of evofosfamide and mTORi. Evofosfamide reduced the increased hypoxia induced by mTORi. Combination treatment induced increased DNA damage, decreased cell proliferation, and decreased survivin. Addition of mTORi did not change evofosfamide-mediated cytotoxicity in 786-O or Caki-1 cells in vitro which might suggest cell non-autonomous effects, specifically increased tumor hypoxia, are important for the in vivo combination activity. Taken together, evofosfamide potentiates the antitumor efficacy of mTOR inhibitors and inhibits the increased tumor hypoxia caused by mTOR inhibition. These studies provide a translational rationale for combining evofosfamide with mTOR inhibitors in clinical studies. PMID:26328245

  13. Preclinical assessment of the absorption and disposition of the phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor GDC-0980 and prediction of its pharmacokinetics and efficacy in human.

    PubMed

    Salphati, Laurent; Pang, Jodie; Plise, Emile G; Lee, Leslie B; Olivero, Alan G; Prior, Wei Wei; Sampath, Deepak; Wong, Susan; Zhang, Xiaolin

    2012-09-01

    (S)-1-{4-[2-(2-Amino-pyrimidin-5-yl)-7-methyl-4-morpholin-4-yl-thieno[3,2-d]pyrimidin-6-ylmethyl]-piperazin-1-yl}-2-hydroxy-propan-1-one (GDC-0980) is a potent and selective inhibitor of phosphatidylinositol 3-kinase (PI3K) and mammalian target of rapamycin, two key components of the PI3K pathway, the deregulation of which is associated with the development of many cancers. The objectives of these studies were to characterize the absorption and disposition of GDC-0980 and assess its efficacy in an MCF7-neo/HER2 human breast cancer xenograft model in immunocompromised mice. Studies in parental Madin-Darby canine kidney cells indicated that GDC-0980 had high permeability (P(app) = 18 10?? cm/s), suggesting good absorption potential. However, it was found to be a P-glycoprotein and breast cancer resistance protein substrate in transfected cells and in knockout mice studies. Plasma protein binding was low, with the fraction unbound ranging from 29 to 52% across species. GDC-0980 hepatic clearance (CL) was predicted to be low in all of the species tested from hepatocyte incubations. The plasma CL of GDC-0980 was low in mouse (6.30 ml min? kg?), rat (15.4 ml min? kg?), and dog (6.37 ml min? kg?) and moderate in cynomolgus monkey (18.9 ml min? kg?). Oral bioavailability ranged from 14.4% in monkey to 125% in dog. Predicted human plasma CL and volume of distribution using allometry were 5.1 ml min? kg? and 1.8 l/kg, respectively. Parameters estimated from the pharmacokinetic/pharmacodynamic modeling of the MCF7-neo/HER2 xenograft data indicated that the GDC-0980 plasma concentration required for tumor stasis was approximately 0.5 ?M. These parameters, combined with the predicted human pharmacokinetic profile, suggested that 55 mg once daily may be a clinically efficacious dose. GDC-0980 preclinical characterization and the predictions of its human properties supported its clinical development; it is currently in Phase II clinical trials. PMID:22696419

  14. Challenges for Preclinical Investigations of Human Biofield Modalities.

    PubMed

    Gronowicz, Gloria; Bengston, William; Yount, Garret

    2015-11-01

    Preclinical models for studying the effects of the human biofield have great potential to advance our understanding of human biofield modalities, which include external qigong, Johrei, Reiki, therapeutic touch, healing touch, polarity therapy, pranic healing, and other practices. A short history of Western biofield studies using preclinical models is presented and demonstrates numerous and consistent examples of human biofields significantly affecting biological systems both in vitro and in vivo. Methodological issues arising from these studies and practical solutions in experimental design are presented. Important questions still left unanswered with preclinical models include variable reproducibility, dosing, intentionality of the practitioner, best preclinical systems, and mechanisms. Input from the biofield practitioners in the experimental design is critical to improving experimental outcomes; however, the development of standard criteria for uniformity of practice and for inclusion of multiple practitioners is needed. Research in human biofield studies involving preclinical models promises a better understanding of the mechanisms underlying the efficacy of biofield therapies and will be important in guiding clinical protocols and integrating treatments with conventional medical therapies. PMID:26665042

  15. Challenges for Preclinical Investigations of Human Biofield Modalities

    PubMed Central

    Gronowicz, Gloria; Bengston, William

    2015-01-01

    Preclinical models for studying the effects of the human biofield have great potential to advance our understanding of human biofield modalities, which include external qigong, Johrei, Reiki, therapeutic touch, healing touch, polarity therapy, pranic healing, and other practices. A short history of Western biofield studies using preclinical models is presented and demonstrates numerous and consistent examples of human biofields significantly affecting biological systems both in vitro and in vivo. Methodological issues arising from these studies and practical solutions in experimental design are presented. Important questions still left unanswered with preclinical models include variable reproducibility, dosing, intentionality of the practitioner, best preclinical systems, and mechanisms. Input from the biofield practitioners in the experimental design is critical to improving experimental outcomes; however, the development of standard criteria for uniformity of practice and for inclusion of multiple practitioners is needed. Research in human biofield studies involving preclinical models promises a better understanding of the mechanisms underlying the efficacy of biofield therapies and will be important in guiding clinical protocols and integrating treatments with conventional medical therapies. PMID:26665042

  16. Role of self-efficacy (SE) and anxiety among pre-clinically disabled older adults when using compensatory strategies to complete daily tasks.

    PubMed

    Higgins, Torrance J; Janelle, Christopher M; Naugle, Kelly M; Knaggs, Jeffrey; Hoover, Brian M; Marsiske, Michael; Manini, Todd M

    2012-01-01

    Classic developmental theory suggests that aging is associated with using compensatory strategies to prolong independence. While compensatory strategies are typically considered positive adaptations, they also signify an early phase in the disablement process - commonly known as pre-clinical disability. To build a better understanding of psychological constructs related to these early signs of disability, we examined the contribution of SE and state anxiety on using compensatory strategies among pre-clinically disabled older adults. Compensatory strategies were observed during performance of daily activities in 257 pre-clinically disabled older adults (67.6 7.04), and SE and state anxiety were evaluated prior to performing each task. In univariate models, lower SE and higher anxiety were associated with more compensation (Spearman correlations: 0.15-0.48, p<0.05). Multivariate logistic regression indicated that low SE [Odds Ratio (OR): 1.70; 95% Confidence Interval (CI): 1.40-2.08) and high anxiety (OR: 1.34; 95% CI: 1.10-1.63) were positively associated with using ?6 compensatory strategies - a level signifying substantial compensation. When considered jointly with SE, the association with anxiety was reversed - higher anxiety demonstrated a lower likelihood of using compensation (OR: 0.70-0.73; 95% CI: 0.50-0.99). The addition of SE might remove the self-defeating cognitions characterizing anxiety allowing the remaining arousal component to appear beneficial. In conclusion, lower SE and higher anxiety are associated with using compensation to complete daily tasks among pre-clinically disabled older adults. Such psychological constructs may contribute to the use of compensatory strategies and represent future intervention targets to help reduce early signs of disability. PMID:22770713

  17. Synthesis, characterization and preclinical studies of two-photon-activated targeted PDT therapeutic triads

    NASA Astrophysics Data System (ADS)

    Spangler, C. W.; Starkey, J. R.; Rebane, A.; Meng, F.; Gong, A.; Drobizhev, M.

    2006-02-01

    Photodynamic therapy (PDT) continues to evolve into a mature clinical treatment of a variety of cancer types as well as age-related macular degeneration of the eye. However, there are still aspects of PDT that need to be improved in order for greater clinical acceptance. While a number of new PDT photo-sensitizers, sometimes referred to as second- or third- generation therapeutic agents, are currently under clinical investigation, the direct treatment through the skin of subcutaneous tumors deeper than 5 mm remains problematic. Currently approved PDT porphyrin photo-sensitizers, as well as several modified porphyrins (e.g. chlorins, bacteriochlorins, etc.) that are under clinical investigation can be activated at 630-730 nm, but none above 800 nm. It would be highly desirable if new PDT paradigms could be developed that would allow photo-activation deep in the tissue transparency window in the Near-infrared (NIR) above 800 nm to reduce scattering and absorption phenomena that reduce deep tissue PDT efficacy. Rasiris and MPA Technologies have developed new porphyrins that have greatly enhanced two-photon absorption ( P A ) cross-sections and can be activated deep in the NIR (ca. 780-850 nm). These porphyrins can be incorporated into a therapeutic triad that also employs an small molecule targeting agent that directs the triad to over-expressed tumor receptor sites, and a NIR onephoton imaging agent that allows tracking the delivery of the triad to the tumor site, as well as clearance of excess triad from healthy tissue prior to the start of PDT treatment. We are currently using these new triads in efficacy studies with a breast cancer cell line that has been transfected with luciferase genes that allow implanted tumor growth and post- PDT treatment efficacy studies in SCID mouse models by following the rise and decay of the bioluminescence signal. We have also designed highly absorbing and scattering collagen breast cancer phantoms in which we have demonstrated dramatic cell kill to a depth of at least 4 cm. We have also demonstrated that at the wavelength and laser fluences used in the treatment of implanted tumors in the mouse mammary fat pads, there is little, if any, damage to the skin or internal mouse organs. In addition, we have also demonstrated that the implanted tumors can be treated to a depth of more than 1 cm by direct radiation through the dorsal side of the mouse.

  18. Systematic Approach to Remediation in Basic Science Knowledge for Preclinical Students: A case study

    NASA Astrophysics Data System (ADS)

    Amara, Francis

    Remediation of pre-clerkship students for deficits in basic science knowledge should help them overcome their learning deficiencies prior to clerkship. However, very little is known about remediation in basic science knowledge during pre-clerkship. This study utilized the program theory framework to collect and organize mixed methods data of the remediation plan for pre-clerkship students who failed their basic science cognitive examinations in a Canadian medical school. This plan was analyzed using a logic model narrative approach and compared to literature on the learning theories. The analysis showed a remediation plan that was strong on governance and verification of scores, but lacked: clarity and transparency of communication, qualified remedial tutors, individualized diagnosis of learner's deficits, and student centered learning. Participants admitted uncertainty about the efficacy of the remediation process. A remediation framework is proposed that includes student-centered participation, individualized learning plan and activities, deliberate practice, feedback, reflection, and rigorous reassessment.

  19. Preclinical and Pilot Clinical Studies of Docetaxel Chemoradiation for Stage III Non-Small-Cell Lung Cancer

    SciTech Connect

    Chen Yuhchyau; Pandya, Kishan J.; Hyrien, Ollivier; Keng, Peter C.; Smudzin, Therese; Anderson, Joy; Qazi, Raman; Smith, Brian; Watson, Thomas J.; Feins, Richard H.; Johnstone, David W.

    2011-08-01

    Purpose: Local and distant failure rates remain high despite aggressive chemoradiation (CRT) treatment for Stage III non-small-cell lung cancer. We conducted preclinical studies of docetaxel's cytotoxic and radiosensitizing effects on lung cancer cell lines and designed a pilot study to target distant micrometastasis upfront with one-cycle induction chemotherapy, followed by low-dose radiosensitizing docetaxel CRT. Methods and Materials: A preclinical study was conducted in human lung cancer cell lines NCI 520 and A549. Cells were treated with two concentrations of docetaxel for 3 h and then irradiated immediately or after a 24-h delay. A clonogenic survival assay was conducted and analyzed for cytotoxic effects vs. radiosensitizing effects of docetaxel. A pilot clinical study was designed based on preclinical study findings. Twenty-two patients were enrolled with a median follow-up of 4 years. Induction chemotherapy consisted of 75 mg/m{sup 2} of docetaxel and 75 mg/m{sup 2} of cisplatin on Day 1 and 150 mg/m{sup 2} of recombinant human granulocyte colony-stimulating factor on Days 2 through 10. Concurrent CRT was started 3 to 6 weeks later with twice-weekly docetaxel at 10 to 12 mg/m{sup 2} and daily delayed radiation in 1.8-Gy fractions to 64.5 Gy for gross disease. Results: The preclinical study showed potent cytotoxic effects of docetaxel and subadditive radiosensitizing effects. Delaying radiation resulted in more cancer cell death. The pilot clinical study resulted in a median survival of 32.6 months for the entire cohort, with 3- and 5-year survival rates of 50% and 19%, respectively, and a distant metastasis-free survival rate of 61% for both 3 and 5 years. A pattern-of-failure analysis showed 75% chest failures and 36% all-distant failures. Therapy was well tolerated with Grade 3 esophagitis observed in 23% of patients. Conclusions: One-cycle full-dose docetaxel/cisplatin induction chemotherapy with recombinant human granulocyte colony-stimulating factor followed by pulsed low-dose docetaxel CRT is promising with regard to its antitumor activity, low rates of distant failure, and low toxicity, suggesting that this regimen deserves further investigation.

  20. Determinants of the Efficacy of Cardiac Ischemic Preconditioning: A Systematic Review and Meta-Analysis of Animal Studies

    PubMed Central

    Wever, Kimberley E.; Hooijmans, Carlijn R.; Riksen, Niels P.; Sterenborg, Thomas B.; Sena, Emily S.; Ritskes-Hoitinga, Merel; Warl, Michiel C.

    2015-01-01

    Background Ischemic preconditioning (IPC) of the heart is a protective strategy in which a brief ischemic stimulus immediately before a lethal ischemic episode potently limits infarct size. Although very promising in animal models of myocardial infarction, IPC has not yet been successfully translated to benefit for patients. Objective To appraise all preclinical evidence on IPC for myocardial infarction and identify factors hampering translation. Methods and results Using systematic review and meta-analysis, we identified 503 animal studies reporting infarct size data from 785 comparisons between IPC-treated and control animals. Overall, IPC reduced myocardial infarction by 24.6% [95%CI 23.5, 25.6]. Subgroup analysis showed that IPC efficacy was reduced in comorbid animals and non-rodents. Efficacy was highest in studies using 23 IPC cycles applied <45 minutes before myocardial infarction. Local and remote IPC were equally effective. Reporting of study quality indicators was low: randomization, blinding and a sample size calculation were reported in 49%, 11% and 2% of publications, respectively. Conclusions Translation of IPC to the clinical setting may be hampered by the observed differences between the animals used in preclinical IPC studies and the patient population, regarding comorbidity, sex and age. Furthermore, the IPC protocols currently used in clinical trials could be optimized in terms of timing and the number of ischemic cycles applied. In order to inform future clinical trials successfully, future preclinical studies on IPC should aim to maximize both internal and external validity, since poor methodological quality may limit the value of the preclinical evidence. PMID:26580958

  1. Preliminary investigation of 6,7-dihydropyrazolo[1,5-a]pyrazin-4-one derivatives as a novel series of mGlu5 receptor positive allosteric modulators with efficacy in preclinical models of schizophrenia.

    PubMed

    Conde-Ceide, Susana; Alcázar, Jesús; Alonso de Diego, Sergio A; López, Silvia; Martín-Martín, María Luz; Martínez-Viturro, Carlos M; Pena, Miguel-Angel; Tong, Han Min; Lavreysen, Hilde; Mackie, Claire; Bridges, Thomas M; Daniels, J Scott; Niswender, Colleen M; Jones, Carrie K; Macdonald, Gregor J; Steckler, Thomas; Conn, P Jeffrey; Stauffer, Shaun R; Lindsley, Craig W; Bartolomé-Nebreda, José Manuel

    2016-01-15

    As part of our efforts to identify a suitable back-up compound to our recently disclosed mGlu5 positive allosteric modulator (PAM) clinical candidate VU0490551/JNJ-46778212, this letter details the investigation and challenges of a novel series of 6,7-dihydropyrazolo[1,5-a]pyrazin-4-one derivatives. From these efforts, compound 4k emerged as a potent and selective mGlu5 PAM displaying overall attractive in vitro (pharmacological and ADMET) and PK profiles combined with in vivo efficacy in preclinical models of schizophrenia. However, further advancement of the compound was precluded due to severely limiting CNS-related side-effects confirming the previously reported association between excessive mGlu5 activation and target-related toxicities. PMID:26684851

  2. Prazosin addition to fluvoxamine: A preclinical study and open clinical trial in OCD.

    PubMed

    Feenstra, Matthijs G P; Klompmakers, André; Figee, Martijn; Fluitman, Sjoerd; Vulink, Nienke; Westenberg, Herman G M; Denys, Damiaan

    2016-02-01

    The efficacy of selective serotonin reuptake inhibitors (SRIs) in psychiatric disorders may be "augmented" through the addition of atypical antipsychotic drugs. A synergistic increase in dopamine (DA) release in the prefrontal cortex has been suggested to underlie this augmentation effect, though the mechanism of action is not clear yet. We used in vivo microdialysis in rats to study DA release following the administration of combinations of fluvoxamine (10mg/kg) and quetiapine (10mg/kg) with various monoamine-related drugs. The results confirmed that the selective 5-HT1A antagonist WAY-100635 (0.05mg/kg) partially blocked the fluvoxamine-quetiapine synergistic effect (maximum DA increase dropped from 325% to 214%). A novel finding is that the α1-adrenergic blocker prazosin (1mg/kg), combined with fluvoxamine, partially mimicked the effect of augmentation (maximum DA increase 205%; area-under-the-curve 163%). As this suggested that prazosin augmentation might be tested in a clinical study, we performed an open clinical trial of prazosin 20mg addition to SRI in therapy-resistant patients with obsessive-compulsive disorder applying for neurosurgery. A small, non-significant reduction in Yale Brown Obsessive Compulsive Scale (Y-BOCS) scores was observed in 10 patients and one patient was classified as a responder with a reduction in Y-BOCS scores of more than 25%. We suggest that future clinical studies augmenting SRIs with an α1-adrenergic blocker in less treatment resistant cases should be considered. The clinical trial "Prazosin in combination with a serotonin reuptake inhibitor for patients with Obsessive Compulsive disorder: an open label study" was registered at 24/05/2011 under trial number ISRCTN61562706: http://www.controlled-trials.com/ISRCTN61562706. PMID:26712326

  3. Mechanisms of aortic aneurysm formation: translating preclinical studies into clinical therapies.

    PubMed

    Davis, Frank M; Rateri, Debra L; Daugherty, Alan

    2014-10-01

    Aneurysms are common in the abdominal and thoracic regions of the aorta. While generally asymptomatic, progression of aneurysms is associated with the devastating consequences of aortic rupture. Current therapeutic options to prevent rupture are restricted to surgical repair, as there remains a lack of validated pharmaceutical approaches. Absence of proven medical therapies may be a consequence of the paucity of knowledge on mechanisms of aneurysmal initiation, progression and rupture. Many potential therapeutic targets have been identified in several widely used animal models of these diseases. A small number of these targets are currently under clinical evaluation, while many more are in preclinical stages of evaluation. The purpose of this review is to: (1) overview current understanding of mechanisms of aneurysmal initiation and progression and (2) summarise medical therapies that have been investigated clinically, as well as highlight future therapeutic targets. PMID:25060754

  4. Therapeutic Vaccination in Chronic Hepatitis B: Preclinical Studies in the Woodchuck

    PubMed Central

    Kosinska, Anna D.; Zhang, Ejuan; Lu, Mengji; Roggendorf, Michael

    2010-01-01

    Recommended treatment of chronic hepatitis B with interferon-α and/or nucleos(t)ide analogues does not lead to a satisfactory result. Induction of HBV-specific T cells by therapeutic vaccination or immunotherapies may be an innovative strategy to overcome virus persistence. Vaccination with commercially available HBV vaccines in patients did not result in effective control of HBV infection, suggesting that new formulations of therapeutic vaccines are needed. The woodchuck (Marmota monax) is a useful preclinical model for developing the new therapeutic approaches in chronic hepadnaviral infections. Several innovative approaches combining antiviral treatments with nucleos(t)ide analogues, DNA vaccines, and protein vaccines were tested in the woodchuck model. In this paper we summarize the available data concerning therapeutic immunization and gene therapy using recombinant viral vectors approaches in woodchucks, which show encouraging results. In addition, we present potential innovations in immunomodulatory strategies to be evaluated in this animal model. PMID:21188201

  5. Preclinical Studies on the Pharmacokinetics, Safety and Toxicology of Oxfendazole: Toward First in Human Studies

    PubMed Central

    Codd, Ellen E.; Ng, Hanna H.; McFarlane, Claire; Riccio, Edward S.; Doppalapudi, Rupa; Mirsalis, Jon C.; Horton, R. John; Gonzalez, Armando E.; Garcia, H. Hugo; Gilman, Robert H.

    2015-01-01

    A two-week study in rats identified target organs of oxfendazole toxicity to be bone marrow, epididymis, liver, spleen, testis, and thymus. Female rats had greater oxfendazole exposure and exhibited toxicities at lower doses than did males. Decreased WBC levels, a class effect of benzimidazole anthelminthics, returned to normal during the recovery period. The NOAEL was determined to be >5 but < 25 mg/kg/d and the MTD 100 mg/kg/d. The highest dose, 200 mg/kg/d resulted in significant toxicity and mortality, leading to euthanization of the main study animals in this group after seven days. Oxfendazole did not exhibit genetic toxicology signals in standard Ames bacterial, mouse lymphoma or rat micronucleus assays, nor did it provoke safety concerns when evaluated for behavioral effects in rats or cardiovascular safety effects in dogs. These results support the transition of oxfendazole to First in Human safety studies preliminary to its evaluation in human helminth diseases. PMID:25701764

  6. Nanomedicines for cancer therapy: state-of-the-art and limitations to pre-clinical studies that hinder future developments

    PubMed Central

    Dawidczyk, Charlene M.; Russell, Luisa M.; Searson, Peter C.

    2014-01-01

    The ability to efficiently deliver a drug or gene to a tumor site is dependent on a wide range of factors including circulation time, interactions with the mononuclear phagocyte system, extravasation from circulation at the tumor site, targeting strategy, release from the delivery vehicle, and uptake in cancer cells. Nanotechnology provides the possibility of creating delivery systems where the design constraints are decoupled, allowing new approaches for reducing the unwanted side effects of systemic delivery, increasing tumor accumulation, and improving efficacy. The physico-chemical properties of nanoparticle-based delivery platforms introduce additional complexity associated with pharmacokinetics, tumor accumulation, and biodistribution. To assess the impact of nanoparticle-based delivery systems, we first review the design strategies and pharmacokinetics of FDA-approved nanomedicines. Next we review nanomedicines under development, summarizing the range of nanoparticle platforms, strategies for targeting, and pharmacokinetics. We show how the lack of uniformity in preclinical trials prevents systematic comparison and hence limits advances in the field. PMID:25202689

  7. Pre-clinical and clinical walking kinematics in female breeding pigs with lameness: A nested case-control cohort study.

    PubMed

    Stavrakakis, S; Guy, J H; Syranidis, I; Johnson, G R; Edwards, S A

    2015-07-01

    Gait profiles were investigated in a cohort of female pigs experiencing a lameness period prevalence of 29% over 17 months. Gait alterations before and during visually diagnosed lameness were evaluated to identify the best quantitative clinical lameness indicators and early predictors for lameness. Pre-breeding gilts (n= 84) were recruited to the study over a period of 6 months, underwent motion capture every 5 weeks and, depending on their age at entry to the study, were followed for up to three successive gestations. Animals were subject to motion capture in each parity at 8 weeks of gestation and on the day of weaning (28 days postpartum). During kinematic motion capture, the pigs walked on the same concrete walkway and an array of infra-red cameras was used to collect three dimensional coordinate data of reflective skin markers attached to the head, trunk and limb anatomical landmarks. Of 24 pigs diagnosed with lameness, 19 had preclinical gait records, whilst 18 had a motion capture while lame. Depending on availability, data from one or two preclinical motion capture 1-11 months prior to lameness and on the day of lameness were analysed. Lameness was best detected and evaluated using relative spatiotemporal gait parameters, especially vertical head displacement and asymmetric stride phase timing. Irregularity in the step-to-stride length ratio was elevated (deviation  ≥ 0.03) in young pigs which presented lameness in later life (odds ratio 7.2-10.8). PMID:25986130

  8. Preclinical studies on the pharmacokinetics, safety, and toxicology of oxfendazole: toward first in human studies.

    PubMed

    Codd, Ellen E; Ng, Hanna H; McFarlane, Claire; Riccio, Edward S; Doppalapudi, Rupa; Mirsalis, Jon C; Horton, R John; Gonzalez, Armando E; Garcia, H Hugo; Gilman, Robert H

    2015-01-01

    A 2-week study in rats identified target organs of oxfendazole toxicity to be bone marrow, epididymis, liver, spleen, testis, and thymus. Female rats had greater oxfendazole exposure and exhibited toxicities at lower doses than did males. Decreased white blood cell levels, a class effect of benzimidazole anthelmintics, returned to normal during the recovery period. The no observed adverse effect level was determined to be >5 but <25 mg/kg/d and the maximum tolerated dose 100 mg/kg/d. The highest dose, 200 mg/kg/d, resulted in significant toxicity and mortality, leading to euthanization of the main study animals in this group after 7 days. Oxfendazole did not exhibit genetic toxicology signals in standard Ames bacterial, mouse lymphoma, or rat micronucleus assays nor did it provoke safety concerns when evaluated for behavioral effects in rats or cardiovascular safety effects in dogs. These results support the transition of oxfendazole to First in Human safety studies preliminary to its evaluation in human helminth diseases. PMID:25701764

  9. Study Skills Course Impact on Academic Self-Efficacy

    ERIC Educational Resources Information Center

    Wernersbach, Brenna M.; Crowley, Susan L.; Bates, Scott C.; Rosenthal, Carol

    2014-01-01

    Although study skills courses improve student retention, the impact of study skills courses on students' academic self-efficacy has not been investigated. The present study examined pre- and posttest levels of academic self-efficacy in college students enrolled in a study skills course (n = 126) compared to students enrolled in a general education…

  10. Employing a gain-of-function factor IX variant R338L to advance the efficacy and safety of hemophilia B human gene therapy: preclinical evaluation supporting an ongoing adeno-associated virus clinical trial.

    PubMed

    Monahan, Paul E; Sun, Junjiang; Gui, Tong; Hu, Genlin; Hannah, William B; Wichlan, David G; Wu, Zhijian; Grieger, Joshua C; Li, Chengwen; Suwanmanee, Thipparat; Stafford, Darrel W; Booth, Carmen J; Samulski, Jade J; Kafri, Tal; McPhee, Scott W J; Samulski, R Jude

    2015-02-01

    Vector capsid dose-dependent inflammation of transduced liver has limited the ability of adeno-associated virus (AAV) factor IX (FIX) gene therapy vectors to reliably convert severe to mild hemophilia B in human clinical trials. These trials also identified the need to understand AAV neutralizing antibodies and empty AAV capsids regarding their impact on clinical success. To address these safety concerns, we have used a scalable manufacturing process to produce GMP-grade AAV8 expressing the FIXR338L gain-of-function variant with minimal (<10%) empty capsid and have performed comprehensive dose-response, biodistribution, and safety evaluations in clinically relevant hemophilia models. The scAAV8.FIXR338L vector produced greater than 6-fold increased FIX specific activity compared with wild-type FIX and demonstrated linear dose responses from doses that produced 2-500% FIX activity, associated with dose-dependent hemostasis in a tail transection bleeding challenge. More importantly, using a bleeding model that closely mimics the clinical morbidity of hemophilic arthropathy, mice that received the scAAV8.FIXR338L vector developed minimal histopathological findings of synovitis after hemarthrosis, when compared with mice that received identical doses of wild-type FIX vector. Hemostatically normal mice (n=20) and hemophilic mice (n=88) developed no FIX antibodies after peripheral intravenous vector delivery. No CD8(+) T cell liver infiltrates were observed, despite the marked tropism of scAAV8.FIXR338L for the liver in a comprehensive biodistribution evaluation (n=60 animals). With respect to the role of empty capsids, we demonstrated that in vivo FIXR338L expression was not influenced by the presence of empty AAV particles, either in the presence or absence of various titers of AAV8-neutralizing antibodies. Necropsy of FIX(-/-) mice 8-10 months after vector delivery revealed no microvascular or macrovascular thrombosis in mice expressing FIXR338L (plasma FIX activity, 100-500%). These preclinical studies demonstrate a safety:efficacy profile supporting an ongoing phase 1/2 human clinical trial of the scAAV8.FIXR338L vector (designated BAX335). PMID:25419787

  11. Employing a Gain-of-Function Factor IX Variant R338L to Advance the Efficacy and Safety of Hemophilia B Human Gene Therapy: Preclinical Evaluation Supporting an Ongoing Adeno-Associated Virus Clinical Trial

    PubMed Central

    Sun, Junjiang; Gui, Tong; Hu, Genlin; Hannah, William B.; Wichlan, David G.; Wu, Zhijian; Grieger, Joshua C.; Li, Chengwen; Suwanmanee, Thipparat; Stafford, Darrel W.; Booth, Carmen J.; Samulski, Jade J.; Kafri, Tal; McPhee, Scott W.J.

    2015-01-01

    Abstract Vector capsid dose-dependent inflammation of transduced liver has limited the ability of adeno-associated virus (AAV) factor IX (FIX) gene therapy vectors to reliably convert severe to mild hemophilia B in human clinical trials. These trials also identified the need to understand AAV neutralizing antibodies and empty AAV capsids regarding their impact on clinical success. To address these safety concerns, we have used a scalable manufacturing process to produce GMP-grade AAV8 expressing the FIXR338L gain-of-function variant with minimal (<10%) empty capsid and have performed comprehensive doseresponse, biodistribution, and safety evaluations in clinically relevant hemophilia models. The scAAV8.FIXR338L vector produced greater than 6-fold increased FIX specific activity compared with wild-type FIX and demonstrated linear dose responses from doses that produced 2500% FIX activity, associated with dose-dependent hemostasis in a tail transection bleeding challenge. More importantly, using a bleeding model that closely mimics the clinical morbidity of hemophilic arthropathy, mice that received the scAAV8.FIXR338L vector developed minimal histopathological findings of synovitis after hemarthrosis, when compared with mice that received identical doses of wild-type FIX vector. Hemostatically normal mice (n=20) and hemophilic mice (n=88) developed no FIX antibodies after peripheral intravenous vector delivery. No CD8+ T cell liver infiltrates were observed, despite the marked tropism of scAAV8.FIXR338L for the liver in a comprehensive biodistribution evaluation (n=60 animals). With respect to the role of empty capsids, we demonstrated that in vivo FIXR338L expression was not influenced by the presence of empty AAV particles, either in the presence or absence of various titers of AAV8-neutralizing antibodies. Necropsy of FIX/ mice 810 months after vector delivery revealed no microvascular or macrovascular thrombosis in mice expressing FIXR338L (plasma FIX activity, 100500%). These preclinical studies demonstrate a safety:efficacy profile supporting an ongoing phase 1/2 human clinical trial of the scAAV8.FIXR338L vector (designated BAX335). PMID:25419787

  12. Quantitative determination of zolmitriptan in rat blood and cerebrospinal fluid by reversed phase HPLC-ESI-MS/MS analysis: application to in vivo preclinical pharmacokinetic study.

    PubMed

    Dalpiaz, Alessandro; Marchetti, Nicola; Cavazzini, Alberto; Pasti, Luisa; Velaga, Sitaram; Gavini, Elisabetta; Beggiato, Sarah; Ferraro, Luca

    2012-07-15

    A fast HPLC-ESI-MS/MS method has been developed and validated for the quantification of the potent and selective antimigraine zolmitriptan in rat blood and cerebrospinal fluid (CSF). The assay has been then applied for in vivo preclinical studies. The analytical determination has been used to obtain pharmacokinetics of zolmitriptan in the two biological matrices after its intravenous or nasal administration. Liquid-liquid extraction of zolmitriptan was performed from 100 ?L rat blood samples in the presence of N(6)-cyclopentyladenosine (internal standard) with the employment of ethyl acetate. Calibration standards were prepared by using blood matrix and following the same liquid-liquid extraction procedure. CSF samples were analyzed without any pre-treatment steps and by using an external calibration method in pure water matrix. Chromatographic separation was performed under reversed phase and a gradient elution condition on a C18 packed column (100 2.0 mm, 2.5 ?m particles diameter). The mobile phase was a mixture between acetonitrile, water and formic acid (0.1% v/v). The applied HPLC-MS/MS method allowed low limits of detection, as calculated from calibration curves, of 6.6 and 24.4 ng/mL for water matrix and rat blood extracts, respectively. Linearity of the calibration curves was established up to 5 ?M (1.44 ?g/mL), as well as good assay accuracy. The intravenous infusion of 20 ?g zolmitriptan to male Sprague-Dawley rats produced blood concentrations ranging from 9.40.7 to 1.240.07 ?g/mL within 10 h, with a terminal half-life of 3.40.2h. The nasal administration of a water suspension of 20 ?g zolmitriptan produced blood concentrations ranging from 2.920.21 to 0.850.07 ?g/mL within 6h. One hour after zolmitriptan intravenous infusion or nasal administration, its CSF concentrations were 0.05390.0016 and 0.04530.0012 ?g/mL, respectively. This study determined the suitability of the herein proposed method to investigate the pharmacokinetics of zolmitriptan after its administration by means of novel formulations and, hence, to evaluate the efficacy of innovative nose-to-brain drug delivery in preclinical studies. PMID:22743338

  13. Reproducibility of Results in Preclinical Studies: A Perspective From the Bone Field

    PubMed Central

    Manolagas, Stavros C.; Kronenberg, Henry M.

    2015-01-01

    The biomedical research enterpriseand the public support for itis predicated on the belief that discoveries and the conclusions drawn from them can be trusted to build a body of knowledge which will be used to improve human health. As in all other areas of scientific inquiry, knowledge and understanding grow by layering new discoveries upon earlier ones. The process self-corrects and distills knowledge by discarding false ideas and unsubstantiated claims. Although self-correction is inexorable in the long-term, in recent years biomedical scientists and the public alike have become alarmed and deeply troubled by the fact that many published results cannot be reproduced. The chorus of concern reached a high pitch with a recent commentary from the NIH Director, Francis S. Collins, and Principal Deputy Director, Lawrence A. Tabak, and their announcement of specific plans to enhance reproducibility of preclinical research that relies on animal models. In this invited perspective, we highlight the magnitude of the problem across biomedical fields and address the relevance of these concerns to the field of bone and mineral metabolism. We also suggest how our specialty journals, our scientific organizations, and our community of bone and mineral researchers can help to overcome this troubling trend. PMID:24916175

  14. Therapeutic vaccination and immunomodulation in the treatment of chronic hepatitis B: preclinical studies in the woodchuck.

    PubMed

    Kosinska, Anna D; Liu, Jia; Lu, Mengji; Roggendorf, Michael

    2015-02-01

    Infection with hepatitis B virus (HBV) may lead to subclinical, acute or chronic hepatitis. In the prevaccination era, HBV infections were endemic due to frequent mother to child transmission in large regions of the world. However, there are still estimated 240 million chronic HBV carriers today and ca. 620,000 patients die per year due to HBV-related liver diseases. Recommended treatment of chronic hepatitis B with interferon-α and/or nucleos(t)ide analogues does not lead to satisfactory results. Induction of HBV-specific T cells by therapeutic vaccination or immunomodulation may be an innovative strategy to overcome virus persistence. Vaccination with commercially available HBV vaccines in patients with or without therapeutic reduction of viral load did not result in effective immune control of HBV infection, suggesting that combination of antiviral treatment with new formulations of therapeutic vaccines is needed. The woodchuck (Marmota monax) and its HBV-like woodchuck hepatitis virus are a useful preclinical animal model for developing new therapeutic approaches in chronic hepadnaviral infections. Several innovative approaches combining antiviral treatments using nucleos(t)ide analogues, with prime-boost vaccination using DNA vaccines, new hepadnaviral antigens or recombinant adenoviral vectors were tested in the woodchuck model. In this review, we summarize these encouraging results obtained with these therapeutic vaccines. In addition, we present potential innovations in immunostimulatory strategies by blocking the interaction of the inhibitory programmed death receptor 1 with its ligand in this animal model. PMID:25535101

  15. Reproducibility of results in preclinical studies: a perspective from the bone field.

    PubMed

    Manolagas, Stavros C; Kronenberg, Henry M

    2014-10-01

    The biomedical research enterprise-and the public support for it-is predicated on the belief that discoveries and the conclusions drawn from them can be trusted to build a body of knowledge which will be used to improve human health. As in all other areas of scientific inquiry, knowledge and understanding grow by layering new discoveries upon earlier ones. The process self-corrects and distills knowledge by discarding false ideas and unsubstantiated claims. Although self-correction is inexorable in the long-term, in recent years biomedical scientists and the public alike have become alarmed and deeply troubled by the fact that many published results cannot be reproduced. The chorus of concern reached a high pitch with a recent commentary from the NIH Director, Francis S. Collins, and Principal Deputy Director, Lawrence A. Tabak, and their announcement of specific plans to enhance reproducibility of preclinical research that relies on animal models. In this invited perspective, we highlight the magnitude of the problem across biomedical fields and address the relevance of these concerns to the field of bone and mineral metabolism. We also suggest how our specialty journals, our scientific organizations, and our community of bone and mineral researchers can help to overcome this troubling trend. PMID:24916175

  16. Taking Journal Clubs off Autopilot: A Case Study of Teaching Literature Evaluation Skills to Preclinical MD/PhD Students

    PubMed Central

    Currier, Rebecca L.; Schneider, Marguerite Reid; Heubi, James E.

    2014-01-01

    Researchers designed learner-directed journal clubs to develop literature evaluation skills in preclinical students. Sessions balanced student-led discussion with structured objectives and faculty support. During the pilot with preclinical MD/PhD students, self-rated mastery improved over all 17 measured objectives. Six exercises have since been incorporated into the full medical school curriculum. PMID:24634798

  17. Taking Journal Clubs off Autopilot: A Case Study of Teaching Literature Evaluation Skills to Preclinical MD/PhD Students.

    PubMed

    Currier, Rebecca L; Schneider, Marguerite Reid; Heubi, James E

    2013-12-01

    Researchers designed learner-directed journal clubs to develop literature evaluation skills in preclinical students. Sessions balanced student-led discussion with structured objectives and faculty support. During the pilot with preclinical MD/PhD students, self-rated mastery improved over all 17 measured objectives. Six exercises have since been incorporated into the full medical school curriculum. PMID:24634798

  18. The therapeutic potential of renin angiotensin aldosterone system (RAAS) in chronic pain: from preclinical studies to clinical trials.

    PubMed

    Bessaguet, Flavien; Magy, Laurent; Desmoulière, Alexis; Demiot, Claire

    2016-03-01

    The prevalence rate of chronic pain is 15% to 25% in adults while the therapeutic arsenal is still insufficient, especially in relieving neuropathic pain. Peripheral pain transmission is conducted by the small Aδ and C sensory nerve fibres. They express elements from the renin-angiotensin-aldosterone system (RAAS), a well-known blood pressure regulator. Recently, studies have demonstrated the role of angiotensin II, its derivatives and aldosterone in the modulation of pain perception, by interacting with receptors expressed by sensory nerve fibres or through the central nervous system. Here, we assess the effects of RAAS modulators in the conduction of pain with molecular, preclinical and clinical approaches, in normal or pathological conditions. Currently, some clinical studies have been carried out on the pain-relieving effect of RAAS modulators and suggest their potential in the management of chronic, inflammatory or neuropathic pain. PMID:26852820

  19. The Relationship between Lesson Study and Self-Efficacy

    ERIC Educational Resources Information Center

    Sibbald, Tim

    2009-01-01

    This article addresses a gap in the literature by developing a theory that bridges lesson study and self-efficacy. Since self-efficacy has been linked to student achievement, the theory is important as an explanatory mechanism linking lesson study to student achievement. The theory was developed using grounded theory based on primary source data

  20. A 2??2 factorial design for the combination therapy of minocycline and remote ischemic perconditioning: efficacy in a preclinical trial in murine thromboembolic stroke model

    PubMed Central

    2014-01-01

    Background After the failure of so many drugs and therapies for acute ischemic stroke, innovative approaches are needed to develop new treatments. One promising strategy is to test combinations of agents in the pre-hospital setting prior to the administration of intravenous tissue plasminogen activator (IV-tPA) and/ or the use of mechanical reperfusion devices in the hospital. Methods We performed a 2??2 factorial design preclinical trial where we tested minocycline (MINO), remote ischemic perconditioning (RIPerC) and their combination treatment in a thromboembolic clot model of stroke in mice, without IV-tPA or later treated with IV-tPA at 4hours post-stroke. Cerebral blood flow (CBF) was measured by laser speckle contrast imaging (LSCI), behavioral outcomes as neurological deficit score (NDS) and adhesive tape removal test, and infarct size measurement were performed at 48hours post-stroke. Mice within the experimental sets were randomized for the different treatments, and all outcome measures were blinded. Results RIPerC significantly improved CBF as measured by LSCI in both with and without tPA treated mice (P?pre-clinical 2 2 design can be easily translated into a pre-hospital clinical trial. PMID:25337387

  1. Preclinical profile of cabazitaxel

    PubMed Central

    Vrignaud, Patricia; Semiond, Dorothée; Benning, Veronique; Beys, Eric; Bouchard, Hervé; Gupta, Sunil

    2014-01-01

    First-generation taxanes have changed the treatment paradigm for a wide variety of cancers, but innate or acquired resistance frequently limits their use. Cabazitaxel is a novel second-generation taxane developed to overcome such resistance. In vitro, cabazitaxel showed similar antiproliferative activity to docetaxel in taxane-sensitive cell lines and markedly greater activity in cell lines resistant to taxanes. In vivo, cabazitaxel demonstrated excellent antitumor activity in a broad spectrum of docetaxel-sensitive tumor xenografts, including a castration-resistant prostate tumor xenograft, HID28, where cabazitaxel exhibited greater efficacy than docetaxel. Importantly, cabazitaxel was also active against tumors with innate or acquired resistance to docetaxel, suggesting therapeutic potential for patients progressing following taxane treatment and those with docetaxel-refractory tumors. In patients with tumors of the central nervous system (CNS), and in patients with pediatric tumors, therapeutic success with first-generation taxanes has been limited. Cabazitaxel demonstrated greater antitumor activity than docetaxel in xenograft models of CNS disease and pediatric tumors, suggesting potential clinical utility in these special patient populations. Based on therapeutic synergism observed in an in vivo tumor model, cabazitaxel is also being investigated clinically in combination with cisplatin. Nonclinical evaluation of the safety of cabazitaxel in a range of animal species showed largely reversible changes in the bone marrow, lymphoid system, gastrointestinal tract, and male reproductive system. Preclinical safety signals of cabazitaxel were consistent with the previously reported safety profiles of paclitaxel and docetaxel. Clinical observations with cabazitaxel were consistent with preclinical results, and cabazitaxel is indicated, in combination with prednisone, for the treatment of patients with hormone-refractory metastatic prostate cancer previously treated with docetaxel. In conclusion, the demonstrated activity of cabazitaxel in tumors with innate or acquired resistance to docetaxel, CNS tumors, and pediatric tumors made this agent a candidate for further clinical evaluation in a broader range of patient populations compared with first-generation taxanes. PMID:25378905

  2. A gender study investigating physics self-efficacy

    NASA Astrophysics Data System (ADS)

    Sawtelle, Vashti

    The underrepresentation of women in physics has been well documented and a source of concern for both policy makers and educators. My dissertation focuses on understanding the role self-efficacy plays in retaining students, particularly women, in introductory physics. I use an explanatory mixed methods approach to first investigate quantitatively the influence of self-efficacy in predicting success and then to qualitatively explore the development of self-efficacy. In the initial quantitative studies, I explore the utility of self-efficacy in predicting the success of introductory physics students, both women and men. Results indicate that self-efficacy is a significant predictor of success for all students. I then disaggregate the data to examine how self-efficacy develops differently for women and men in the introductory physics course. Results show women rely on different sources of self-efficacy than do men, and that a particular instructional environment, Modeling Instruction, has a positive impact on these sources of self-efficacy. In the qualitative phase of the project, this dissertation focuses on the development of self-efficacy. Using the qualitative tool of microanalysis, I introduce a methodology for understanding how self-efficacy develops moment-by-moment using the lens of self-efficacy opportunities. I then use the characterizations of self-efficacy opportunities to focus on a particular course environment and to identify and describe a mechanism by which Modeling Instruction impacts student self-efficacy. Results indicate that the emphasizing the development and deployment of models affords opportunities to impact self-efficacy. The findings of this dissertation indicate that introducing key elements into the classroom, such as cooperative group work, model development and deployment, and interaction with the instructor, create a mechanism by which instructors can impact the self-efficacy of their students. Results from this study indicate that creating a model to impact the retention rates of women in physics should include attending to self-efficacy and designing activities in the classroom that create self-efficacy opportunities.

  3. Are All Dentiform Teeth with Simulated Caries the Same? A Six-Year Retrospective Study in Preclinical Operative Dentistry.

    PubMed

    Delgado, Alex J; Walter, Ricardo; Behar-Horenstein, Linda S; Boushell, Lee W

    2015-11-01

    Dentiform teeth with simulated caries (DTSC), frequently used in preclinical courses, should show no variability in the amount of simulated caries from tooth to tooth. However, the level of caries variability among DTSC is currently unknown. The aim of this study was to assess the variation in simulated caries levels in one group of DTSC and determine whether variation among DTSC impacted the preclinical performance of dental students. In the study, 80 commercially available mandibular first molar DTSC with simulated mesio-occluso-distal caries were sectioned in coronal (n=40) and sagittal (n=40) planes where the caries depth/width was greatest. Section images were analyzed for variation in levels of simulated caries using image-processing software. Three years of practical performance data using DTSC were compared with three years of practical performance data using dentiform teeth without simulated caries, for a total of six years (students' performance on two exams, Practical 1 and Practical 2). The results showed that 70% of the coronally sectioned teeth had manufacturing defects that resulted in caries overextension at the dentino-enamel junctions (DEJs). Overextensions were found at the DEJ in 41.3% of the sagittally sectioned teeth. There was a statistically significant decrease in Practical 1 performance of the students who used DTSC as compared with students who used teeth without simulated caries (p=0.0001); there was no statistically significant difference on Practical 2 performance. Of the DTSC evaluated in this study, 56.6% contained manufacturing defects, and more than 80% were found to have excessive caries variation. Prediction of which DTSC will have caries overextension is not possible. Students preparing DTSC that contain caries overextension are therefore at increased risk of receiving undeserved negative summative assessment on practical examinations. PMID:26522639

  4. Analysis of machine perfusion benefits in kidney grafts: a preclinical study

    PubMed Central

    2011-01-01

    Background Machine perfusion (MP) has potential benefits for marginal organs such as from deceased from cardiac death donors (DCD). However, there is still no consensus on MP benefits. We aimed to determine machine perfusion benefits on kidney grafts. Methods We evaluated kidney grafts preserved in ViaspanUW or KPS solutions either by CS or MP, in a DCD pig model (60 min warm ischemia + 24 h hypothermic preservation). Endpoints were: function recovery, quality of function during follow up (3 month), inflammation, fibrosis, animal survival. Results ViaspanUW-CS animals did not recover function, while in other groups early follow up showed similar values for kidney function. Alanine peptidase and ?-NAG activities in the urine were higher in CS than in MP groups. Oxydative stress was lower in KPS-MP animals. Histology was improved by MP over CS. Survival was 0% in ViaspanUW-CS and 60% in other groups. Chronic inflammation, epithelial-to-mesenchymal transition and fibrosis were lowest in KPS-MP, followed by KPS-CS and ViaspanUW-MP. Conclusions With ViaspanUW, effects of MP are obvious as only MP kidney recovered function and allowed survival. With KPS, the benefits of MP over CS are not directly obvious in the early follow up period and only histological analysis, urinary tubular enzymes and red/ox status was discriminating. Chronic follow-up was more conclusive, with a clear superiority of MP over CS, independently of the solution used. KPS was proven superior to ViaspanUW in each preservation method in terms of function and outcome. In our pre-clinical animal model of DCD transplantation, MP offers critical benefits. PMID:21266040

  5. NIH initiative to balance sex of animals in preclinical studies: generative questions to guide policy, implementation, and metrics

    PubMed Central

    2014-01-01

    In May of 2014, the NIH Director together with the Director of the Office of Research on Womens Health announced plans to take a multi-dimensional approach to address the over reliance on male cells and animals in preclinical research. The NIH is engaging the scientific community in the development of policies to improve the sex balance in research. The present, past, and future presidents of the Organization for the Study of Sex Differences, in order to encourage thoughtful discussion among scientists, pose a series of questions to generate ideas in three areas: 1. research strategies, 2. educational strategies, and 3. strategies to monitor effectiveness of policies to improve the sex balance in research. By promoting discussion within the scientific community, a consensus will evolve that will move science forward in a productive and effective manner. PMID:25780556

  6. Two years later: journals are not yet enforcing the ARRIVE guidelines on reporting standards for pre-clinical animal studies.

    PubMed

    Baker, David; Lidster, Katie; Sottomayor, Ana; Amor, Sandra

    2014-01-01

    There is growing concern that poor experimental design and lack of transparent reporting contribute to the frequent failure of pre-clinical animal studies to translate into treatments for human disease. In 2010, the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines were introduced to help improve reporting standards. They were published in PLOS Biology and endorsed by funding agencies and publishers and their journals, including PLOS, Nature research journals, and other top-tier journals. Yet our analysis of papers published in PLOS and Nature journals indicates that there has been very little improvement in reporting standards since then. This suggests that authors, referees, and editors generally are ignoring guidelines, and the editorial endorsement is yet to be effectively implemented. PMID:24409096

  7. (99m)Tc-amitrole as a novel selective imaging probe for solid tumor: In silico and preclinical pharmacological study.

    PubMed

    Essa, B M; Sakr, T M; Khedr, Mohammed A; El-Essawy, F A; El-Mohty, A A

    2015-08-30

    Lactoperoxidase (LPO) inhibitors are very selective for solid tumor due to their high binding affinity to the LPO enzyme. A computational study was used to select top-ranked LPO inhibitor (alone and in complex with (99m)Tc) with high in silico affinity. The novel prepared (99m)Tc-amitrole complex demonstrated both in silico and in vivo high affinity toward solid tumors.(99m)Tc-amitrole was radio-synthesized with a high radiochemical yield (89.7±3.25). It showed in vitro stability for up to 6h. Its preclinical evaluation in solid tumor-bearing mice showed high retention and biological accumulation in solid tumor cells with a high Target/Non-Target (T/NT) ratio equal to 4.9 at 60min post-injection. The data described previously could recommend (99m)Tc-amitrole as potential targeting scintigraphic probe for solid tumor imaging. PMID:25956074

  8. Is Science the Only Driver in Species Selection? An Internal Study to Evaluate Compound Requirements in the Minipig Compared to the Dog in Preclinical Studies.

    PubMed

    Schaefer, Kai; Rensing, Susanne; Hillen, Heinz; Burkhardt, John E; Germann, Paul-Georg

    2016-04-01

    Dogs have been often chosen as a nonrodent species for preclinical development of small molecule drugs mainly due to availability and relative ease of handling. Recently, focus has increased on the minipig as a potential alternative to the dog, based on either scientific rationale or public opinion concerns. There are, however, other factors influencing nonrodent choices, in particular drug amount and synthesis time, which differ between species and therefore may impact the milestones of a drug development program. To assess the magnitude of compound need, a retrospective internal survey was conducted on drug amounts used in dog studies which were translated into the requirements for minipigs. Compound need approximately doubles if minipigs are used. Costs of compound are accordingly higher, and synthesis times are slightly increased. In our company, the differences were not considered significant enough to preclude the use of minipigs if the later preclinical program might benefit from improved human risk prediction. PMID:26839331

  9. Self-Efficacy and Collaborative Learning: An Intervention Study

    ERIC Educational Resources Information Center

    Robertson, Jane

    2012-01-01

    Findings from empirical research suggest that both self-efficacy beliefs and collaborative learning may have an influence upon student academic performance. However, the phenomena of self-efficacy beliefs, collaborative learning, and academic achievement have not been studied in concert with one another. Using quantitative research methods, I…

  10. Evaluation of dietetic product innovations: the relative role of preclinical and clinical studies.

    PubMed

    Makrides, Maria; Gibson, Robert A

    2010-01-01

    A variety of systems are used to establish efficacy of food ingredients. Immortal human cell lines have the advantage of rapid throughput and often have the ability to point to mechanisms of action. Transgenic and natural variants of animals (usually rats and mice) have proven to be extremely useful in elucidating effects in vivo, although extrapolation of results to humans has risks. Animal models are also useful in establishing safety and toxic levels of ingredients. Human trials have the most relevance to society. Types of evidence for efficacy rise from improved status level in subjects as a result of eating food (long-chain polyunsaturated fatty acid, levels in erythrocytes), change in surrogate markers as a result of eating food (plasma cholesterol or glutathione peroxidase activity), change in a physiological outcome (such as visual evoked potential acuity or heart rate variability) through to the highest level of evidence, a change in a clinical outcome (improved global development, reduction in infections) established in randomized controlled trials. Ultimately, there is a need for tests of pragmatic interventions that can easily be incorporated into usual dietary practices of the culture in which it is tested. PMID:20664222

  11. N-aryl piperazine metabotropic glutamate receptor 5 positive allosteric modulators possess efficacy in preclinical models of NMDA hypofunction and cognitive enhancement.

    PubMed

    Gregory, K J; Herman, E J; Ramsey, A J; Hammond, A S; Byun, N E; Stauffer, S R; Manka, J T; Jadhav, S; Bridges, T M; Weaver, C D; Niswender, C M; Steckler, T; Drinkenburg, W H; Ahnaou, A; Lavreysen, H; Macdonald, G J; Bartolom, J M; Mackie, C; Hrupka, B J; Caron, M G; Daigle, T L; Lindsley, C W; Conn, P J; Jones, C K

    2013-11-01

    Impaired transmission through glutamatergic circuits has been postulated to play a role in the underlying pathophysiology of schizophrenia. Furthermore, inhibition of the N-methyl-d-aspartate (NMDA) subtype of ionotropic glutamate receptors (NMDAR) induces a syndrome that recapitulates many of the symptoms observed in patients with schizophrenia. Selective activation of metabotropic glutamate receptor subtype 5 (mGlu5) may provide a novel therapeutic approach for treatment of symptoms associated with schizophrenia through facilitation of transmission through central glutamatergic circuits. Here, we describe the characterization of two novel N-aryl piperazine mGlu5 positive allosteric modulators (PAMs): 2-(4-(2-(benzyloxy)acetyl)piperazin-1-yl)benzonitrile (VU0364289) and 1-(4-(2,4-difluorophenyl)piperazin-1-yl)-2-((4-fluorobenzyl)oxy)ethanone (DPFE). VU0364289 and DPFE induced robust leftward shifts in the glutamate concentration-response curves for Ca(2+) mobilization and extracellular signal-regulated kinases 1 and 2 phosphorylation. Both PAMs displayed micromolar affinity for the common mGlu5 allosteric binding site and high selectivity for mGlu5. VU0364289 and DPFE possessed suitable pharmacokinetic properties for dosing in vivo and produced robust dose-related effects in reversing amphetamine-induced hyperlocomotion, a preclinical model predictive of antipsychotic-like activity. In addition, DPFE enhanced acquisition of contextual fear conditioning in rats and reversed behavioral deficits in a mouse model of NMDAR hypofunction. In contrast, DPFE had no effect on reversing apomorphine-induced disruptions of prepulse inhibition of the acoustic startle reflex. These mGlu5 PAMs also increased monoamine levels in the prefrontal cortex, enhanced performance in a hippocampal-mediated memory task, and elicited changes in electroencephalogram dynamics commensurate with procognitive effects. Collectively, these data support and extend the role for the development of novel mGlu5 PAMs for the treatment of psychosis and cognitive deficits observed in individuals with schizophrenia. PMID:23965381

  12. N-Aryl Piperazine Metabotropic Glutamate Receptor 5 Positive Allosteric Modulators Possess Efficacy in Preclinical Models of NMDA Hypofunction and Cognitive Enhancement

    PubMed Central

    Gregory, K.J.; Herman, E.J.; Ramsey, A.J.; Hammond, A.S.; Byun, N.E.; Stauffer, S.R.; Manka, J.T.; Jadhav, S.; Bridges, T.M.; Weaver, C.D.; Niswender, C.M.; Steckler, T.; Drinkenburg, W.H.; Ahnaou, A.; Lavreysen, H.; Macdonald, G.J.; Bartolom, J.M.; Mackie, C.; Hrupka, B.J.; Caron, M.G.; Daigle, T.L.; Lindsley, C.W.; Conn, P.J.

    2013-01-01

    Impaired transmission through glutamatergic circuits has been postulated to play a role in the underlying pathophysiology of schizophrenia. Furthermore, inhibition of the N-methyl-d-aspartate (NMDA) subtype of ionotropic glutamate receptors (NMDAR) induces a syndrome that recapitulates many of the symptoms observed in patients with schizophrenia. Selective activation of metabotropic glutamate receptor subtype 5 (mGlu5) may provide a novel therapeutic approach for treatment of symptoms associated with schizophrenia through facilitation of transmission through central glutamatergic circuits. Here, we describe the characterization of two novel N-aryl piperazine mGlu5 positive allosteric modulators (PAMs): 2-(4-(2-(benzyloxy)acetyl)piperazin-1-yl)benzonitrile (VU0364289) and 1-(4-(2,4-difluorophenyl)piperazin-1-yl)-2-((4-fluorobenzyl)oxy)ethanone (DPFE). VU0364289 and DPFE induced robust leftward shifts in the glutamate concentration-response curves for Ca2+ mobilization and extracellular signal-regulated kinases 1 and 2 phosphorylation. Both PAMs displayed micromolar affinity for the common mGlu5 allosteric binding site and high selectivity for mGlu5. VU0364289 and DPFE possessed suitable pharmacokinetic properties for dosing in vivo and produced robust dose-related effects in reversing amphetamine-induced hyperlocomotion, a preclinical model predictive of antipsychotic-like activity. In addition, DPFE enhanced acquisition of contextual fear conditioning in rats and reversed behavioral deficits in a mouse model of NMDAR hypofunction. In contrast, DPFE had no effect on reversing apomorphine-induced disruptions of prepulse inhibition of the acoustic startle reflex. These mGlu5 PAMs also increased monoamine levels in the prefrontal cortex, enhanced performance in a hippocampal-mediated memory task, and elicited changes in electroencephalogram dynamics commensurate with procognitive effects. Collectively, these data support and extend the role for the development of novel mGlu5 PAMs for the treatment of psychosis and cognitive deficits observed in individuals with schizophrenia. PMID:23965381

  13. Generation, characterization and preclinical studies of a human anti-L1CAM monoclonal antibody that cross-reacts with rodent L1CAM.

    PubMed

    Cho, Seulki; Park, Insoo; Kim, Haejung; Jeong, Mun Sik; Lim, Mooney; Lee, Eung Suk; Kim, Jin Hong; Kim, Semi; Hong, Hyo Jeong

    2016-01-01

    L1 cell adhesion molecule (L1CAM) is aberrantly expressed in malignant tumors and plays important roles in tumor progression. Thus, L1CAM could serve as a therapeutic target and anti-L1CAM antibodies may have potential as anticancer agents. However, L1CAM is expressed in neural cells and the druggability of anti-L1AM antibody must be validated at the earliest stages of preclinical study. Here, we generated a human monoclonal antibody that is cross-reactive with mouse L1CAM and evaluated its pharmacokinetic properties and anti-tumor efficacy in rodent models. First, we selected an antibody (Ab4) that binds human and mouse L1CAM from the human nave Fab library using phage display, then increased its affinity 45-fold through mutation of 3 residues in the complementarity-determining regions (CDRs) to generate Ab4M. Next, the affinity of Ab4M was increased 1.8-fold by yeast display of single-chain variable fragment containing randomly mutated light chain CDR3 to generate Ab417. The affinities (KD) of Ab417 for human and mouse L1CAM were 0.24nM and 79.16 pM, respectively. Ab417 specifically bound the Ig5 domain of L1CAM and did not exhibit off-target activity, but bound to the peripheral nerves embedded in normal human tissues as expected in immunohistochemical analysis. In a pharmacokinetics study, the mean half-life of Ab417 was 114.49h when a single dose (10mg/kg) was intravenously injected into SD rats. Ab417 significantly inhibited tumor growth in a human cholangiocarcinoma xenograft nude mouse model and did not induce any adverse effect in in vivo studies. Thus, Ab417 may have potential as an anticancer agent. PMID:26785809

  14. Ramucirumab: preclinical research and clinical development

    PubMed Central

    Aprile, Giuseppe; Rijavec, Erika; Fontanella, Caterina; Rihawi, Karim; Grossi, Francesco

    2014-01-01

    Ramucirumab (IMC-1121B, LY3009806), a fully humanized monoclonal antibody directed against the extracellular domain of vascular endothelial growth factor receptor 2 (VEGFR-2), is a new therapeutic option that selectively inhibits the human VEGFR-2 with a much greater affinity than its natural ligands. Based on the promising results of both preclinical and early clinical studies, ramucirumab has been tested in different tumor types either alone or in combination with chemotherapy. While it has recently been granted its first US Food and Drug Administration approval for use as a single agent in patients with advanced or metastatic gastric cancer or gastroesophageal junction carcinoma, its role for metastatic breast cancer or advanced non-small-cell lung cancer is still debated. The aims of this review are to recall and discuss the most significant preclinical and clinical studies that led to the development of ramucirumab and to present the results of the randomized clinical trials that have tested its efficacy in different malignancies, including gastric and lung cancer. PMID:25378934

  15. Preclinical study of using multiphoton microscopy to diagnose liver cancer and differentiate benign and malignant liver lesions

    NASA Astrophysics Data System (ADS)

    Yan, Jun; Zhuo, Shuangmu; Chen, Gang; Wu, Xiufeng; Zhou, Dong; Xie, Shusen; Jiang, Jiahao; Ying, Mingang; Jia, Fan; Chen, Jianxin; Zhou, Jian

    2012-02-01

    Recently, the miniaturized multiphoton microscopy (MPM) and multiphoton probe allow the clinical use of multiphoton endoscopy for diagnosing cancer via ``optical biopsy''. The purpose of this study was to establish MPM optical diagnostic features for liver cancer and evaluate the sensitivity, specificity, and accuracy of MPM optical diagnosis. Firstly, we performed a pilot study to establish the MPM diagnostic features by investigating 60 surgical specimens, and found that high-resolution MPM images clearly demonstrated apparent differences between benign and malignant liver lesions in terms of their tissue architecture and cell morphology. Cancer cells, characterized by irregular size and shape, enlarged nuclei, and increased nuclear-cytoplasmic ratio, were identified by MPM images, which were comparable to hematoxylin-eosin staining images. Secondly, we performed a blinded study to evaluate the sensitivity, specificity, and accuracy of MPM optical diagnosis by investigating another 164 specimens, and found that the sensitivity, specificity, and accuracy of MPM diagnosis was 96.32%, 96.43%, and 96.34%, respectively. In conclusion, it is feasible to use MPM to diagnose liver cancer and differentiate benign and malignant liver lesions. This preclinical study provides the groundwork for further using multiphoton endoscopy to perform real-time noninvasive ``optical biopsy'' for liver lesions in the near future.

  16. Pre-clinical studies of Notch signaling inhibitor RO4929097 in inflammatory breast cancer cells.

    PubMed

    Debeb, Bisrat G; Cohen, Evan N; Boley, Kimberly; Freiter, Erik M; Li, Li; Robertson, Fredika M; Reuben, James M; Cristofanilli, Massimo; Buchholz, Thomas A; Woodward, Wendy A

    2012-07-01

    Basal breast cancer, common among patients presenting with inflammatory breast cancer (IBC), has been shown to be resistant to radiation and enriched in cancer stem cells. The Notch pathway plays an important role in self-renewal of breast cancer stem cells and contributes to inflammatory signaling which promotes the breast cancer stem cell phenotype. Herein, we inhibited Notch signaling using a gamma secretase inhibitor, RO4929097, in an in vitro model that enriches for cancer initiating cells (3D clonogenic assay) and conventional 2D clonogenic assay to compare the effect on radiosensitization of the SUM149 and SUM190 IBC cell lines. RO4929097 downregulated the Notch target genes Hes1, Hey1, and HeyL, and showed a significant reduction in anchorage independent growth in SUM190 and SUM149. However, the putative self-renewal assay mammosphere formation efficiency was increased with the drug. To assess radiosensitization of putative cancer stem cells, cells were exposed to increasing doses of radiation with or without 1 ?M RO4929097 in their standard (2D) and self-renewal enriching (3D) culture conditions. In the conventional 2D clonogenic assay, RO4929097 significantly sensitized SUM190 cells to ionizing radiation and has a modest radiosensitization effect in SUM149 cells. In the 3D clonogenic assays, however, a radioprotective effect was seen in both SUM149 and SUM190 cells at higher doses. Both cell lines express IL-6 and IL-8 cytokines known to mediate the efficacy of Notch inhibition and to promote self-renewal of stem cells. We further showed that RO429097 inhibits normal T-cell synthesis of some inflammatory cytokines, including TNF-?, a potential mediator of IL-6 and IL-8 production in the microenvironment. These data suggest that additional targeting agents may be required to selectively target IBC stem cells through Notch inhibition, and that evaluation of microenvironmental influences may shed further light on the potential effects of this inhibitor. PMID:22547109

  17. Does Bacillus anthracis Lethal Toxin Directly Depress Myocardial Function? A Review of Clinical Cases and Preclinical Studies.

    PubMed

    Suffredini, Dante A; Sampath-Kumar, Hanish; Li, Yan; Ohanjanian, Lernik; Remy, Kenneth E; Cui, Xizhong; Eichacker, Peter Q

    2015-01-01

    The US outbreak of B.anthracis infection in 2001 and subsequent cases in the US and Europe demonstrate that anthrax is a continuing risk for the developed world. While several bacterial components contribute to the pathogenesis of B. anthracis, production of lethal toxin (LT) is strongly associated with the development of hypotension and lethality. However, the mechanisms underlying the cardiovascular instability LT produces are unclear. Some evidence suggests that LT causes shock by impairing the peripheral vasculature, effects consistent with the substantial extravasation of fluid in patients dying with B. anthracis. Other data suggests that LT directly depresses myocardial function. However a clinical correlate for this latter possibility is less evident since functional studies and post-mortem examination in patients demonstrate absent or minimal cardiac changes. The purposes of this review were to first present clinical studies of cardiac functional and histologic pathology with B. anthracis infection and to then examine in vivo, in vitro, and ex vivo preclinical studies of LT's myocardial effects. Together, these data suggest that it is unclear whether that LT directly depresses cardiac function. This question is important for the clinical management and development of new therapies for anthrax and efforts should continue to be made to answer it. PMID:26703730

  18. Does Bacillus anthracis Lethal Toxin Directly Depress Myocardial Function? A Review of Clinical Cases and Preclinical Studies

    PubMed Central

    Suffredini, Dante A.; Sampath-Kumar, Hanish; Li, Yan; Ohanjanian, Lernik; Remy, Kenneth E.; Cui, Xizhong; Eichacker, Peter Q.

    2015-01-01

    The US outbreak of B.anthracis infection in 2001 and subsequent cases in the US and Europe demonstrate that anthrax is a continuing risk for the developed world. While several bacterial components contribute to the pathogenesis of B. anthracis, production of lethal toxin (LT) is strongly associated with the development of hypotension and lethality. However, the mechanisms underlying the cardiovascular instability LT produces are unclear. Some evidence suggests that LT causes shock by impairing the peripheral vasculature, effects consistent with the substantial extravasation of fluid in patients dying with B. anthracis. Other data suggests that LT directly depresses myocardial function. However a clinical correlate for this latter possibility is less evident since functional studies and post-mortem examination in patients demonstrate absent or minimal cardiac changes. The purposes of this review were to first present clinical studies of cardiac functional and histologic pathology with B. anthracis infection and to then examine in vivo, in vitro, and ex vivo preclinical studies of LT’s myocardial effects. Together, these data suggest that it is unclear whether that LT directly depresses cardiac function. This question is important for the clinical management and development of new therapies for anthrax and efforts should continue to be made to answer it. PMID:26703730

  19. Photodynamic therapy with the phthalocyanine photosensitizer Pc 4: The case experience with preclinical mechanistic and early clinical-translational studies

    SciTech Connect

    Miller, Janine D.; Scull, Heather

    2007-11-01

    Photodynamic therapy (PDT) is emerging as a promising non-invasive treatment for cancers. PDT involves either local or systemic administration of a photosensitizing drug, which preferentially localizes within the tumor, followed by illumination of the involved organ with light, usually from a laser source. Here, we provide a selective overview of our experience with PDT at Case Western Reserve University, specifically with the silicon phthalocyanine photosensitizer Pc 4. We first review our in vitro studies evaluating the mechanism of cell killing by Pc 4-PDT. Then we briefly describe our clinical experience in a Phase I trial of Pc 4-PDT and our preliminary translational studies evaluating the mechanisms behind tumor responses. Preclinical work identified (a) cardiolipin and the anti-apoptotic proteins Bcl-2 and Bcl-xL as targets of Pc 4-PDT, (b) the intrinsic pathway of apoptosis, with the key participation of caspase-3, as a central response of many human cancer cells to Pc 4-PDT, (c) signaling pathways that could modify apoptosis, and (d) a formulation by which Pc 4 could be applied topically to human skin and penetrate at least through the basal layer of the epidermis. Clinical-translational studies enabled us to develop an immunohistochemical assay for caspase-3 activation, using biopsies from patients treated with topical Pc 4 in a Phase I PDT trial for cutaneous T-cell lymphoma. Results suggest that this assay may be used as an early biomarker of clinical response.

  20. Preclinical safety and efficacy of an antiHIV-1 lentiviral vector containing a short hairpin RNA to CCR5 and the C46 fusion inhibitor

    PubMed Central

    Wolstein, Orit; Boyd, Maureen; Millington, Michelle; Impey, Helen; Boyer, Joshua; Howe, Annett; Delebecque, Frederic; Cornetta, Kenneth; Rothe, Michael; Baum, Christopher; Nicolson, Tamara; Koldej, Rachel; Zhang, Jane; Keech, Naomi; Camba Coln, Joanna; Breton, Louis; Bartlett, Jeffrey; An, Dong Sung; Chen, Irvin SY; Burke, Bryan; Symonds, Geoff P

    2014-01-01

    Gene transfer has therapeutic potential for treating HIV-1 infection by generating cells that are resistant to the virus. We have engineered a novel self-inactivating lentiviral vector, LVsh5/C46, using two viral-entry inhibitors to block early steps of HIV-1 cycle. The LVsh5/C46 vector encodes a short hairpin RNA (shRNA) for downregulation of CCR5, in combination with the HIV-1 fusion inhibitor, C46. We demonstrate here the effective delivery of LVsh5/C46 to human T cell lines, peripheral blood mononuclear cells, primary CD4+ T lymphocytes, and CD34+ hematopoietic stem/progenitor cells (HSPC). CCR5-targeted shRNA (sh5) and C46 peptide were stably expressed in the target cells and were able to effectively protect gene-modified cells against infection with CCR5- and CXCR4-tropic strains of HIV-1. LVsh5/C46 treatment was nontoxic as assessed by cell growth and viability, was noninflammatory, and had no adverse effect on HSPC differentiation. LVsh5/C46 could be produced at a scale sufficient for clinical development and resulted in active viral particles with very low mutagenic potential and the absence of replication-competent lentivirus. Based on these in vitro results, plus additional in vivo safety and efficacy data, LVsh5/C46 is now being tested in a phase 1/2 clinical trial for the treatment of HIV-1 disease. PMID:26015947

  1. Pre-Clinical studies of Notch Signaling Inhibitor RO4929097 in Inflammatory Breast Cancer Cells

    PubMed Central

    Debeb, Bisrat G.; Cohen, Evan N.; Boley, Kimberly; Freiter, Erik M.; Li, Li; Robertson, Fredika M.; Reuben, James M.; Cristofanilli, Massimo; Buchholz, Thomas A.; Woodward, Wendy A.

    2015-01-01

    Basal breast cancer, common among patients presenting with inflammatory breast cancer, has been shown to be resistant to radiation and enriched in cancer stem cells. The Notch pathway plays an important role in self-renewal of breast cancer stem cells and contributes to inflammatory signaling that promotes the breast cancer stem cell phenotype. Herein we inhibited Notch signaling using a gamma secretase inhibitor, RO4929097, in an in vitro model that enriches for cancer initiating cells (3D clonogenic assay) and conventional 2D clonogenic assay to compare the effect on radiosensitization of the SUM149 and SUM190 inflammatory breast cancer (IBC) cell lines. RO4929097 downregulated the Notch target genes Hes1, Hey1 and HeyL and showed a significant reduction in anchorage independent growth in SUM190 and SUM149. However, the putative self-renewal assay mammosphere formation efficiency was increased with the drug. To assess radiosensitization of putative cancer stem cells, cells were exposed to increasing doses of radiation with or without 1uM RO4929097 in their standard (2D) and self-renewal enriching (3D) culture conditions. In the conventional 2D clonogenic assay, RO4929097 significantly sensitized SUM190 cells to ionizing radiation and has a modest radiosensitization effect in SUM149 cells. In the 3D clonogenic assays, however, a radioprotective effect was seen in both SUM149 and SUM190 cells at higher doses. Both cell lines express IL-6 and IL-8, cytokines known to mediate the efficacy of notch inhibition and to promote self-renewal of stem cells. We further showed that RO429097 inhibits normal T-cell synthesis of some inflammatory cytokines, including TNF-α, a potential mediator of IL-6 and IL-8 production in the microenvironment. These data suggest additional targeting agents may be required to selectively target IBC stem cells through notch inhibition, and that evaluation of microenvironmental influences may shed further light on the potential effects of this inhibitor. PMID:22547109

  2. [Preclinical study of immunocorrection action of the sum of active substances of Coluria geoides (Pall.) Ledeb. (Rosaceae)].

    PubMed

    Dutova, S V; Karpova, M R; Myadelets, M A; Myasnaya, N V; Sherstoboev, E Yu

    2015-01-01

    A preclinical study of the immunocorrection action of the sum of active substances isolated from ethereal-oil plants Coluria geoides (Pall.) Ledeb. (Rosaceae family) with respect to experimental immunodeficiency showed that preparations relieve symptoms of immunodeficiency caused by the administration of cyclophosphan: suppressed synthesis of anti-erythrocyte antibodies (agglutinine) and proliferative processes in the spleen. Under the influence of C. geoides preparations, the absolute numbers of cariocytes and antibody forming cells in spleen significantly increased (compared to the group of animals with experimental immunodeficiency) and in some cases reached the background level. The drugs studied produced a more pronounced stimulating effect on the synthesis of specific immunoglobulins and proliferation of antibody forming cells of spleen as compared to the effect of Echinacea tincture. Preparation C-2 (extract from underground organs and grass of C. geoides obtained by percolation method with 70% ethanol) is most promising for in-depth research and the development of new effective drugs with immunocorrecting properties. PMID:26036007

  3. The discovery of rivaroxaban: translating preclinical assessments into clinical practice

    PubMed Central

    Kubitza, Dagmar; Perzborn, Elisabeth; Berkowitz, Scott D.

    2013-01-01

    Direct oral anticoagulants that target a single coagulation factor (such as factor Xa or thrombin) have been developed in recent years in an attempt to address some of the limitations of traditional anticoagulants. Rivaroxaban is an oral, direct factor Xa inhibitor that inhibits free and clot-bound factor Xa and factor Xa in the prothrombinase complex. Preclinical studies demonstrated a potent anticoagulant effect of rivaroxaban in plasma as well as the ability of this agent to prevent and treat venous and arterial thrombosis in animal models. These studies led to an extensive phase I clinical development program that investigated the pharmacological properties of rivaroxaban in humans. In these studies, rivaroxaban was shown to exhibit predictable pharmacokinetics and pharmacodynamics and to have no clinically relevant interactions with many commonly prescribed co-medications. The pharmacodynamic effects of rivaroxaban (for example, inhibition of factor Xa and prolongation of prothrombin time) were closely correlated with rivaroxaban concentrations in plasma. The encouraging findings from preclinical and early clinical studies were expanded upon in large, randomized phase III studies, which demonstrated the clinical efficacy and safety of rivaroxaban in a broad spectrum of patients. This article provides an overview of the discovery and development of rivaroxaban, describing the pharmacodynamic profile established in preclinical studies and the optimal translation to clinical studies in healthy subjects and patient populations. PMID:24324436

  4. Re-evaluate the effect of hyperbaric oxygen therapy in cancer - a preclinical therapeutic small animal model study.

    PubMed

    Pande, Sneha; Sengupta, Amit; Srivastava, Anurag; Gude, Rajiv P; Ingle, Arvind

    2012-01-01

    Tumor hypoxia is a known driver of angiogenesis that also facilitates tumor growth. Moreover, poorly oxygenated central tumor area remains relatively radio or chemo resistant. HBO therapy is known to elevate the levels of dissolved oxygen and eliminates tumor hypoxia. It has been one of the modalities in cancer treatment; therefore its optimization is important. In this experimental study, no cancer enhancing effect was seen during the course of HBO therapy; however, post therapy there was an accelerated growth and progression of tumor. HBO treated mice lived shorter and the response to therapy was dose & tumor volume dependent. HBO therapy probably exert its effect on the cancer proliferating cells through multiple pathways such as increased DNA damage, apoptosis & geno-toxicity leading to slow cancer progression while post therapy tumorigenic effect could be due to impaired DNA repair mechanism, mutagenic effect & aneuploidy as well as altered blood supply & nutrients. Tumor growth reached plateau with time and this finding validated theoretical model predicting tumor reaching an asymptotic limit. While, marked asymmetry observed in tumor volume progression or cancer cell proliferation rate in each of the experimental C3H mouse suggested a need for an alternate small animal pre-clinical cancer therapeutic model. PMID:23144880

  5. Reform in Teaching Preclinical Pathophysiology

    ERIC Educational Resources Information Center

    Li, Yong-Yu; Li, Kun; Yao, Hong; Xu, Xiao-Juan; Cai, Qiao-Lin

    2015-01-01

    Pathophysiology is a scientific discipline that studies the onset and progression of pathological conditions and diseases, and pathophysiology is one of the core courses in most preclinical medical curricula. In China, most medical schools house a Department of Pathophysiology, in contrast to medical schools in many developed countries. The staff…

  6. Reform in Teaching Preclinical Pathophysiology

    ERIC Educational Resources Information Center

    Li, Yong-Yu; Li, Kun; Yao, Hong; Xu, Xiao-Juan; Cai, Qiao-Lin

    2015-01-01

    Pathophysiology is a scientific discipline that studies the onset and progression of pathological conditions and diseases, and pathophysiology is one of the core courses in most preclinical medical curricula. In China, most medical schools house a Department of Pathophysiology, in contrast to medical schools in many developed countries. The staff

  7. Minnelide reduces tumor burden in preclinical models of osteosarcoma

    PubMed Central

    Banerjee, Sulagna; Thayanithy, Venugopal; Sangwan, Veena; Mackenzie, Tiffany N.; Saluja, Ashok K.; Subramanian, Subbaya

    2015-01-01

    Osteosarcoma is the most common bone cancer in children and adolescents with a five-year survival rate of about 70%. In this study, we have evaluated the preclinical therapeutic efficacy of the novel synthetic drug, Minnelide, a prodrug of triptolide on osteosarcoma. Triptolide was effective in significantly inducing apoptosis in all osteosarcoma cell lines tested but had no significant effect on the human osteoblast cells. Notably, Minnelide treatment significantly reduced tumor burden and lung metastasis in the orthotopic and lung colonization models. Triptolide/Minnelide effectively downregulated the levels of pro-survival proteins such as heat shock proteins, cMYC, survivin and targets NF-κB pathway. PMID:23499892

  8. Metabolic phenotyping applied to pre-clinical and clinical studies of acetaminophen metabolism and hepatotoxicity.

    PubMed

    Coen, Muireann

    2015-02-01

    Acetaminophen (APAP, paracetamol, N-acetyl-p-aminophenol) is a widely used analgesic that is safe at therapeutic doses but is a major cause of acute liver failure (ALF) following overdose. APAP-induced hepatotoxicity is related to the formation of an electrophilic reactive metabolite, N-acetyl-p-benzoquinone imine (NAPQI), which is detoxified through conjugation with reduced glutathione (GSH). One method that has been applied to study APAP metabolism and hepatotoxicity is that of metabolic phenotyping, which involves the study of the small molecule complement of complex biological samples. This approach involves the use of high-resolution analytical platforms such as NMR spectroscopy and mass spectrometry to generate information-rich metabolic profiles that reflect both genetic and environmental influences and capture both endogenous and xenobiotic metabolites. Data modeling and mining and the subsequent identification of panels of candidate biomarkers are typically approached with multivariate statistical tools. We review the application of multi-platform metabolic profiling for the study of APAP metabolism in both in vivo models and humans. We also review the application of metabolic profiling for the study of endogenous metabolic pathway perturbations in response to APAP hepatotoxicity, with a particular focus on metabolites involved in the biosynthesis of GSH and those that reflect mitochondrial function such as long-chain acylcarnitines. Taken together, this body of work sheds much light on the mechanism of APAP-induced hepatotoxicity and provides candidate biomarkers that may prove of translational relevance for improved stratification of APAP-induced ALF. PMID:25533740

  9. Choosing preclinical study models of diabetic retinopathy: key problems for consideration

    PubMed Central

    Mi, Xue-Song; Yuan, Ti-Fei; Ding, Yong; Zhong, Jing-Xiang; So, Kwok-Fai

    2014-01-01

    Diabetic retinopathy (DR) is the most common complication of diabetes mellitus in the eye. Although the clinical treatment for DR has already developed to a relative high level, there are still many urgent problems that need to be investigated in clinical and basic science. Currently, many in vivo animal models and in vitro culture systems have been applied to solve these problems. Many approaches have also been used to establish different DR models. However, till now, there has not been a single study model that can clearly and exactly mimic the developmental process of the human DR. Choosing the suitable model is important, not only for achieving our research goals smoothly, but also, to better match with different experimental proposals in the study. In this review, key problems for consideration in choosing study models of DR are discussed. These problems relate to clinical relevance, different approaches for establishing models, and choice of different species of animals as well as of the specific in vitro culture systems. Attending to these considerations will deepen the understanding on current study models and optimize the experimental design for the final goal of preventing DR. PMID:25429204

  10. Self-Efficacy for Pleasing the Instructor: A Validation Study

    ERIC Educational Resources Information Center

    Montalvo, Gregory P.; Mansfield, Eric A.

    2009-01-01

    The purpose of this study was to develop and validate the construct of self-efficacy for pleasing the instructor (SEPI) and explore its usefulness as an alternative to global measures of perceived ability. The results of three studies are presented in this report. Study one was conducted to define the construct SEPI from a student perspective.

  11. Self-Efficacy Perceptions of Social Studies Candidate Teachers

    ERIC Educational Resources Information Center

    Simsek, Nihat

    2011-01-01

    The aim of this study was to determine the self efficacy beliefs of pre-service social studies teachers. For this purpose, the scales developed in various areas were examined, the opinions of experts were taken and a final scale was created to be used for this study. The validity and reliability of the scale were checked. The validity coefficient

  12. Preclinical studies of the potent and selective nicotinic ?4?2 receptor ligand VMY-2-95.

    PubMed

    Kong, Hyesik; Song, Jun-ke; Yenugonda, Venkata Mahidhar; Zhang, Li; Shuo, Tian; Cheema, Amrita K; Kong, Yali; Du, Guan-hua; Brown, Milton L

    2015-02-01

    The discovery and development of small molecules that antagonize neuronal nicotinic acetylcholine receptors may provide new ligands for evaluation in models of depression or addiction. We discovered a small molecule, VMY-2-95, a nAChR ligand with picomolar affinity and high selectivity for ?4?2 receptors. In this study, we investigated its preclinical profile in regards to solubility, lipophilicity, metabolic stability, intestinal permeability, bioavailability, and drug delivery to the rat brain. Metabolic stability of VMY-2-952HCl was monitored on human liver microsomes, and specific activity of VMY-2-952HCl on substrate metabolism by CYP1A2, 2C9, 2C19, 2D6, and 3A4 was tested in a high-throughput manner. The intestinal transport of VMY-2-952HCl was studied through Caco-2 cell monolayer permeability. VMY-2-952HCl was soluble in water and chemically stable, and the apparent partition coefficient was 0.682. VMY-2-952HCl showed significant inhibition of CYP2C9 and 2C19, but weak or no effect on 1A2, 2D6, and 3A4. The Caco-2 cell model studies revealed that VMY-2-952HCl was highly permeable with efflux ratio of 1.11. VMY-2-952HCl achieved a maximum serum concentration of 0.56 mg/mL at 0.9 h and was orally available with a half-life of ?9 h. Furthermore, VMY-2-952HCl was detected in the rat brain after 3 mg/kg oral administration and achieved a maximal brain tissue concentration of 2.3 ?g/g within 60 min. Overall, the results demonstrate that VMY-2-952HCl has good drug like properties and can penetrate the blood-brain barrier with oral administration. PMID:25533629

  13. Pre-Clinical Atherosclerosis due to HIV Infection: Carotid Intima-Medial Thickness Measurements from the FRAM Study

    PubMed Central

    Grunfeld, C.; Delaney, J.A.C.; Wanke, C.; Currier, J.S.; Scherzer, R.; Biggs, M. L.; Tien, P.; Shlipak, M.; Sidney, S.; Polak, J.F.; O'Leary, D.; Bacchetti, P.; Kronmal, R.

    2010-01-01

    Background Cardiovascular disease (CVD) is an increasing cause of morbidity and mortality in HIV-infected patients. However, it is controversial whether HIV infection contributes to accelerated atherosclerosis independent of traditional CVD risk factors. Methods Cross-sectional study of HIV-infected and control subjects without pre-existing CVD from the study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM) and the Multi-Ethnic Study of Atherosclerosis (MESA). Pre-clinical atherosclerosis was assessed by carotid intima-medial thickness (IMT) measurements in the internal/bulb and common regions in HIV-infected and control subjects after adjusting for traditional CVD risk factors. Results For internal carotid, mean IMT was 1.170.50mm for HIV-infected participants and 1.060.58mm for controls (p<0.0001). After multivariable adjustment for demographic characteristics, the mean difference of HIV-infected vs. controls was +0.188mm (95%CI 0.113-0.263, p<0.0001). Further adjustment for traditional CVD risk factors modestly attenuated the HIV association (+0.148mm, 95%CI 0.072-0.224, p=0.0001). For the common carotid, HIV infection was independently associated with greater IMT (+0.033mm, 95%CI 0.010, 0.056, p=0.005). The association of HIV infection with IMT was similar to that of smoking which was also associated with greater IMT (internal +0.173mm, common +0.020mm). Conclusions Even after adjustment for traditional CVD risk factors, HIV infection was accompanied by more extensive atherosclerosis measured by IMT. The stronger association of HIV infection with IMT in the internal/bulb region compared to the common carotid may explain previous discrepancies in the literature. The association of HIV infection with IMT was similar to that of traditional CVD risk factors, such as smoking. PMID:19455012

  14. Quality of Reporting and Adherence to ARRIVE Guidelines in Animal Studies for Chagas Disease Preclinical Drug Research: A Systematic Review.

    PubMed

    Gulin, Julián Ernesto Nicolás; Rocco, Daniela Marisa; García-Bournissen, Facundo

    2015-11-01

    Publication of accurate and detailed descriptions of methods in research articles involving animals is essential for health scientists to accurately interpret published data, evaluate results and replicate findings. Inadequate reporting of key aspects of experimental design may reduce the impact of studies and could act as a barrier to translation of research findings. Reporting of animal use must be as comprehensive as possible in order to take advantage of every study and every animal used. Animal models are essential to understanding and assessing new chemotherapy candidates for Chagas disease pathology, a widespread parasitic disease with few treatment options currently available. A systematic review was carried out to compare ARRIVE guidelines recommendations with information provided in publications of preclinical studies for new anti-Trypanosoma cruzi compounds. A total of 83 publications were reviewed. Before ARRIVE guidelines, 69% of publications failed to report any macroenvironment information, compared to 57% after ARRIVE publication. Similar proportions were observed when evaluating reporting of microenvironmental information (56% vs. 61%). Also, before ARRIVE guidelines publication, only 13% of papers described animal gender, only 18% specified microbiological status and 13% reported randomized treatment assignment, among other essential information missing or incomplete. Unfortunately, publication of ARRIVE guidelines did not seem to enhance reporting quality, compared to papers appeared before ARRIVE publication. Our results suggest that there is a strong need for the scientific community to improve animal use description, animal models employed, transparent reporting and experiment design to facilitate its transfer and application to the affected human population. Full compliance with ARRIVE guidelines, or similar animal research reporting guidelines, would be an excellent start in this direction. PMID:26587586

  15. Quality of Reporting and Adherence to ARRIVE Guidelines in Animal Studies for Chagas Disease Preclinical Drug Research: A Systematic Review

    PubMed Central

    Gulin, Julián Ernesto Nicolás; Rocco, Daniela Marisa; García-Bournissen, Facundo

    2015-01-01

    Publication of accurate and detailed descriptions of methods in research articles involving animals is essential for health scientists to accurately interpret published data, evaluate results and replicate findings. Inadequate reporting of key aspects of experimental design may reduce the impact of studies and could act as a barrier to translation of research findings. Reporting of animal use must be as comprehensive as possible in order to take advantage of every study and every animal used. Animal models are essential to understanding and assessing new chemotherapy candidates for Chagas disease pathology, a widespread parasitic disease with few treatment options currently available. A systematic review was carried out to compare ARRIVE guidelines recommendations with information provided in publications of preclinical studies for new anti-Trypanosoma cruzi compounds. A total of 83 publications were reviewed. Before ARRIVE guidelines, 69% of publications failed to report any macroenvironment information, compared to 57% after ARRIVE publication. Similar proportions were observed when evaluating reporting of microenvironmental information (56% vs. 61%). Also, before ARRIVE guidelines publication, only 13% of papers described animal gender, only 18% specified microbiological status and 13% reported randomized treatment assignment, among other essential information missing or incomplete. Unfortunately, publication of ARRIVE guidelines did not seem to enhance reporting quality, compared to papers appeared before ARRIVE publication. Our results suggest that there is a strong need for the scientific community to improve animal use description, animal models employed, transparent reporting and experiment design to facilitate its transfer and application to the affected human population. Full compliance with ARRIVE guidelines, or similar animal research reporting guidelines, would be an excellent start in this direction. PMID:26587586

  16. Issues in pharmaceutical development of thymosin alpha1 from preclinical studies through marketing.

    PubMed

    Tuthill, Cynthia

    2007-09-01

    SciClone Pharmaceuticals licensed the commercial and patent rights to thymosin alpha1, for geographical regions of the world excluding the United States and Europe, in the early 1990s. With this license, SciClone embarked on global drug development, and the issues encountered for thymosin alpha1 are reflective of the roller coaster of modern approval of pharmaceuticals. Most of the required toxicology studies had been completed prior to licensure, but some newer studies had to be conducted to obtain approvals in certain countries. The recent development of the "International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use" (ICH) guidelines allows for a clearer definition of the required battery of toxicology studies, although some countries still have not adopted these guidelines, and the local regulations have had to be understood and followed. Other hurdles include the complications that manufacturing requirements can differ between countries, and certain countries require local clinical experience trials in addition to SciClone's cumulative clinical data. A further obstacle was the pleiotropic nature of the mechanism of action of thymosin alpha1, with the resulting difficulty in the unraveling of its pharmacologic effects. With close attention to these regulatory details, SciClone has obtained approvals in more than 30 countries and has successfully begun commercial sales. PMID:17947591

  17. Contemporary murine models in preclinical astrocytoma drug development

    PubMed Central

    McNeill, Robert S.; Vitucci, Mark; Wu, Jing; Miller, C. Ryan

    2015-01-01

    Despite 6 decades of research, only 3 drugs have been approved for astrocytomas, the most common malignant primary brain tumors. However, clinical drug development is accelerating with the transition from empirical, cytotoxic therapy to precision, targeted medicine. Preclinical animal model studies are critical for prioritizing drug candidates for clinical development and, ultimately, for their regulatory approval. For decades, only murine models with established tumor cell lines were available for such studies. However, these poorly represent the genomic and biological properties of human astrocytomas, and their preclinical use fails to accurately predict efficacy in clinical trials. Newer models developed over the last 2 decades, including patient-derived xenografts, genetically engineered mice, and genetically engineered cells purified from human brains, more faithfully phenocopy the genomics and biology of human astrocytomas. Harnessing the unique benefits of these models will be required to identify drug targets, define combination therapies that circumvent inherent and acquired resistance mechanisms, and develop molecular biomarkers predictive of drug response and resistance. With increasing recognition of the molecular heterogeneity of astrocytomas, employing multiple, contemporary models in preclinical drug studies promises to increase the efficiency of drug development for specific, molecularly defined subsets of tumors. PMID:25246428

  18. Neural Stem Cell-Mediated Enzyme-Prodrug Therapy for Glioma: Preclinical Studies

    PubMed Central

    Aboody, Karen S.; Najbauer, Joseph; Metz, Marianne Z.; DApuzzo, Massimo; Gutova, Margarita; Annala, Alexander J.; Synold, Timothy W.; Couture, Larry A.; Blanchard, Suzette; Moats, Rex A.; Garcia, Elizabeth; Aramburo, Soraya; Valenzuela, Valerie V.; Frank, Richard T.; Barish, Michael E.; Brown, Christine E.; Kim, Seung U.; Badie, Behnam; Portnow, Jana

    2013-01-01

    High-grade gliomas are extremely difficult to treat because they are invasive and therefore are not curable by surgical resection; the toxicity of currently chemo- and radiation therapies limits the doses that can be used. Neural stem cells (NSCs) have inherent tumor-tropic properties that enable their use as delivery vehicles that can target enzyme/prodrug therapy selectively to tumors. We have used a cytosine deaminase (CD)-expressing clonal human NSC line, HB1.F3.CD, to home to gliomas in mice and locally convert the tumor-localized prodrug 5-fluorocytosine to the active chemotherapeutic 5-fluorouracil. In vitro studies confirmed that the NSCs have normal karyotype, tumor tropism, and CD expression, indicating that these cells are genetically and functionally stable. In vivo biodistribution studies demonstrated that these NSCs retained tumor tropism, even in mice pre-treated with radiation or dexamethasone to mimic clinically relevant adjuvant therapies. We evaluated safety and toxicity after intracerebral administration of the NSCs in non-tumor bearing, and in orthotopic glioma-bearing, immunocompetent and immunodeficient mice. We detected no difference in toxicity associated with conversion of 5-fluorocytosine to 5-fluorouracil, no NSCs outside the brain, and no histological evidence of pathology or tumorigenesis attributable to the NSCs. The average tumor volume in mice that received HB1.F3.CD NSCs and 5-fluorocytosine was approximately one-third that of the average volume in control mice. On the basis of these results, we conclude that combination therapy with HB1.F3.CD NSCs and 5-fluorocytosine is safe, non-toxic and effective in mice. These data have led to approval of a first-inhuman study of an allogeneic NSC-mediated enzyme/prodrug targeted cancer therapy in patients with recurrent high-grade glioma. PMID:23658244

  19. Evaluation of novel acute urinary rat kidney toxicity biomarker for subacute toxicity studies in preclinical trials.

    PubMed

    Fuchs, Tobias Christian; Frick, Katharina; Emde, Barbara; Czasch, Stephanie; von Landenberg, Friedrich; Hewitt, Philip

    2012-10-01

    Novel urinary protein biomarkers for the detection of acute renal damage, recently accepted by the U.S. Food and Drug Administration, European Medicines Agency, and Pharmaceuticals and Medical Devices Agency (Japan), now have to be validated in practice. Limited data regarding the performance of these acute markers after subacute or subchronic treatment are publicly available. To increase the area of applicability of these markers, it is important to evaluate the ability to detect them after 28 days of treatment or even longer. Wistar rats were treated with three doses of cisplatin, vancomycin, or puromycin to induce renal damage. Twelve candidate proteins were measured by Luminex xMAP-based WideScreen assays, MesoScale Discovery-based MULTI-SPOT technology, or RENA-strip dipstick assay after 28 days. Treatment with all three model compounds resulted in a dose-dependent increase in urinary biomarkers, specific for the observed areas within the nephron, determined histopathologically. The most promising biomarkers in this study were NGAL, Kim-1, osteopontin, clusterin, RPA-1, and GSTYb1, detected by multiplexing technologies. The RENA-strip dipstick assay delivered good diagnostic results for vancomycin-treated but not for cisplatin- or puromycin-treated rats. Taken together, the data show that these new biomarkers are robust and measurable for longer term studies to predict different types of kidney toxicities. PMID:22581810

  20. Advancing novel molecular imaging agents from preclinical studies to first-in-humans phase I clinical trials in academia--a roadmap for overcoming perceived barriers.

    PubMed

    Reilly, Raymond M; Lam, Karen; Chan, Conrad; Levine, Mark

    2015-04-15

    There is a critical need to advance promising novel molecular imaging (MI) agents for cancer from preclinical studies to first-in-humans Phase I clinical trials in order to realize their full potential for cancer detection and for predicting or monitoring response to targeted ("personalized") cancer therapies. Steps to clinical translation include radiopharmaceutical formulation, preclinical pharmacology and toxicology studies, clinical trial design and human ethics approval, and regulatory agency submission. In this Topical Review, we provide a "roadmap" to advancing one class of novel MI agents to Phase I trials in academia and illustrate the processes that we have successfully applied for (111)In-labeled pertuzumab, a MI probe for monitoring response of HER2-positive breast cancer to treatment with trastuzumab (Herceptin). We hope that our experience will encourage other academic radiopharmaceutical scientists to embrace this challenge. PMID:25781873

  1. Preclinical studies on histone deacetylase inhibitors as therapeutic reagents for endometrial and ovarian cancers

    PubMed Central

    Singh, Brahma N; Zhou, Hongyuan; Li, Jinping; Tipton, Tracy; Wang, Bin; Shao, Guo; Gilbert, E Nickolas; Li, Qiang; Jiang, Shi-Wen

    2012-01-01

    Histone deacetylases (HDACs) remove acetyl groups from lysine residues of histones and the deacetylation allows for tighter electrostatic interactions between DNA and histones, leading to a more compact chromatin conformation with limited access for transactivators and the suppression of transcription. HDAC mRNA and protein overexpression was observed in endometrial and ovarian cancers. Numerous in vitro studies have shown that HDAC inhibitors, through their actions on histone and nonhistone proteins, are able to reactivate the tumor suppressor genes, inhibit cell cycle progression and induce cell apoptosis in endometrial and ovarian cancer cell cultures. Results from mou se xenograft models also demonstrated the potency of HDAC inhibitors as anticancer reagents when used as single agent or in combination with classical chemotherapy drugs. PMID:22112317

  2. Treating the Developing versus Developed Brain: Translating Preclinical Mouse and Human Studies.

    PubMed

    Casey, B J; Glatt, Charles E; Lee, Francis S

    2015-06-17

    Behaviors and underlying brain circuits show characteristic changes across the lifespan that produce sensitive windows of vulnerability and resilience to psychopathology. Understanding the developmental course of these changes may inform which treatments are best at what ages. Focusing on behavioral domains and neurobiological substrates conserved from mouse to human supports reciprocal hypothesis generation and testing that leverages the strengths of each system in understanding their development. Introducing human genetic variants into mice can further define effects of individual variation on normative development, how they contribute to risk and resilience for mental illness, and inform personalized treatment opportunities. This article emphasizes the period of adolescence, when there is a peak in the emergence of mental illness, anxiety disorders in particular. We present cross-species studies relating fear learning to anxiety across development and discuss how clinical treatments can be optimized for individuals and targeted to the biological states of the developing brain. PMID:26087163

  3. A Preclinical Study of Laryngeal Motor-Evoked Potentials as a Marker Vagus Nerve Activation.

    PubMed

    Grimonprez, Annelies; Raedt, Robrecht; De Taeye, Leen; Larsen, Lars Emil; Delbeke, Jean; Boon, Paul; Vonck, Kristl

    2015-12-01

    Vagus nerve stimulation (VNS) is a treatment for refractory epilepsy and depression. Previous studies using invasive recording electrodes showed that VNS induces laryngeal motor-evoked potentials (LMEPs) through the co-activation of the recurrent laryngeal nerve and subsequent contractions of the laryngeal muscles. The present study investigates the feasibility of recording LMEPs in chronically VNS-implanted rats, using a minimally-invasive technique, to assess effective current delivery to the nerve and to determine optimal VNS output currents for vagal fiber activation. Three weeks after VNS electrode implantation, signals were recorded using an electromyography (EMG) electrode in the proximity of the laryngeal muscles and a reference electrode on the skull. The VNS output current was gradually ramped up from 0.1 to 1.0 mA in 0.1 mA steps. In 13/27 rats, typical LMEPs were recorded at low VNS output currents (median 0.3 mA, IQR 0.2-0.3 mA). In 11/27 rats, significantly higher output currents were required to evoke electrophysiological responses (median 0.7 mA, IQR 0.5-0.7 mA, [Formula: see text]). The latencies of these responses deviated significantly from LMEPs ([Formula: see text]). In 3/27 rats, no electrophysiological responses to simulation were recorded. Minimally invasive LMEP recordings are feasible to assess effective current delivery to the vagus nerve. Furthermore, our results suggest that low output currents are sufficient to activate vagal fibers. PMID:26510476

  4. Ultra-high-resolution imaging of small animals: implications for preclinical and research studies.

    PubMed

    Weber, D A; Ivanovic, M

    1999-01-01

    Recent developments in the use of pinhole SPECT and dedicated PET for UHR small animal imaging have identified the technology that can be used to provide images with spatial resolution of the order of 1 to 3 mm. In SPECT imaging, rotating camera pinhole SPECT has provided the means to use existing equipment to achieve UHR images. It has the disadvantages of low sensitivity and requires special image software to reconstruct tomographic slices. However, with minimal additional cost to an imaging laboratory, pinhole SPECT can provide a quantitatively accurate imaging technique for small-animal studies. New detector technology offers considerable promise; however, more studies are required before any one system can be singled out as offering major advantages over the pinhole SPECT method for general purpose small-animal SPECT imaging. The search for the means to achieve better sensitivity with UHR continues. In PET imaging, with few exceptions, the general trend has been to design systems dedicated to small-animal imaging to achieve UHR images with satisfactory sensitivity for quantitative UHR imaging. Several of the ring configuration, small-animal PET imaging systems provide good sensitivity and high spatial resolution. The cost of many of these systems, however, is relatively high, and investigators continue to explore different detector materials and imaging geometries to develop an instrument with acceptable levels of sensitivity with UHR imaging capability. We believe that both small-animal SPECT and PET imaging techniques now offer practical UHR imaging methods for quantitative small-animal imaging. As these tools are implemented in the investigation of new radiopharmaceuticals, we expect the utility of in vivo small animal assays will support further research in optimizing this technology. PMID:10385189

  5. Preclinical studies identify non-apoptotic low-level caspase-3 as therapeutic target in pemphigus vulgaris.

    PubMed

    Luyet, Camille; Schulze, Katja; Sayar, Beyza S; Howald, Denise; Müller, Eliane J; Galichet, Arnaud

    2015-01-01

    The majority of pemphigus vulgaris (PV) patients suffer from a live-threatening loss of intercellular adhesion between keratinocytes (acantholysis). The disease is caused by auto-antibodies that bind to desmosomal cadherins desmoglein (Dsg) 3 or Dsg3 and Dsg1 in mucous membranes and skin. A currently unresolved controversy in PV is whether apoptosis is involved in the pathogenic process. The objective of this study was to perform preclinical studies to investigate apoptotic pathway activation in PV pathogenesis with the goal to assess its potential for clinical therapy. For this purpose, we investigated mouse and human skin keratinocyte cultures treated with PV antibodies (the experimental Dsg3 monospecific antibody AK23 or PV patients IgG), PV mouse models (passive transfer of AK23 or PVIgG into adult and neonatal mice) as well as PV patients' biopsies (n=6). A combination of TUNEL assay, analyses of membrane integrity, early apoptotic markers such as cleaved poly-ADP-ribose polymerase (PARP) and the collapse of actin cytoskeleton failed to provide evidence for apoptosis in PV pathogenesis. However, the in vitro and in vivo PV models, allowing to monitor progression of lesion formation, revealed an early, transient and low-level caspase-3 activation. Pharmacological inhibition confirmed the functional implication of caspase-3 in major events in PV such as shedding of Dsg3, keratin retraction, proliferation including c-Myc induction, p38MAPK activation and acantholysis. Together, these data identify low-level caspase-3 activation downstream of disrupted Dsg3 trans- or cis-adhesion as a major event in PV pathogenesis that is non-synonymous with apoptosis and represents, unlike apoptotic components, a promising target for clinical therapy. At a broader level, these results posit that an impairment of adhesive functions in concert with low-level, non-lethal caspase-3 activation can evoke profound cellular changes which may be of relevance for other diseases including cancer. PMID:25748204

  6. Virtual reality, augmented reality, and robotics applied to digestive operative procedures: from in vivo animal preclinical studies to clinical use

    NASA Astrophysics Data System (ADS)

    Soler, Luc; Marescaux, Jacques

    2006-04-01

    Technological innovations of the 20 th century provided medicine and surgery with new tools, among which virtual reality and robotics belong to the most revolutionary ones. Our work aims at setting up new techniques for detection, 3D delineation and 4D time follow-up of small abdominal lesions from standard mecial images (CT scsan, MRI). It also aims at developing innovative systems making tumor resection or treatment easier with the use of augmented reality and robotized systems, increasing gesture precision. It also permits a realtime great distance connection between practitioners so they can share a same 3D reconstructed patient and interact on a same patient, virtually before the intervention and for real during the surgical procedure thanks to a telesurgical robot. In preclinical studies, our first results obtained from a micro-CT scanner show that these technologies provide an efficient and precise 3D modeling of anatomical and pathological structures of rats and mice. In clinical studies, our first results show the possibility to improve the therapeutic choice thanks to a better detection and and representation of the patient before performing the surgical gesture. They also show the efficiency of augmented reality that provides virtual transparency of the patient in real time during the operative procedure. In the near future, through the exploitation of these systems, surgeons will program and check on the virtual patient clone an optimal procedure without errors, which will be replayed on the real patient by the robot under surgeon control. This medical dream is today about to become reality.

  7. Preclinical Studies of YK-4-272, an Inhibitor of Class II Histone Deacetylases by Disruption of Nucleocytoplasmic Shuttling

    PubMed Central

    Kong, Hye-Sik; Tian, Shuo; Kong, Yali; Du, Guanhua; Zhang, Li; Jung, Mira; Dritschilo, Anatoly

    2013-01-01

    Purpose The HDAC shuttling inhibitor, YK-4-272 functions by restricting nuclear shuttling of Class II HDACs. Pre-clinical investigations of YK-4-272 bioavailability, pharmacokinetics, in vivo toxicity and tumor growth inhibition were performed to determine its potential as an HDAC shuttling disruptor for use in clinical applications. Methods The solubility, lipophilicity, in vitro metabolic stability, in vitro intestinal permeability, and in vivo pharmacokinetics of YK-4-272 were determined by HPLC methods. The anti-tumor activity of YK-4-272 was determined by monitoring athymic Balb/c nude mice bearing PC-3 xenografts. Results Oral bioavailability of YK-4-272 is supported by its solubility (0.537 mg/mL) and apparent partition coefficient of 2.0. The compound was chemically and metabolically stable and not a substrate for CYP450. In Caco-2 cell transport studies, YK-4-272 was highly permeable. The time-concentration profile of YK- 4-272 in plasma resulted in a Cmax of 2.47 µg/mL at 0.25 h with a AUC of 3.304 µg×h/mL. Treatment of PC-3 tumor xenografts with YK-4-272 showed significant growth delay. Conclusions YK-4-272 is stable and bio-available following oral administration. Growth inhibition of cancer cells and tumors was observed. These studies support advancing YK-4-272 for further evaluation as a novel HDAC shuttling inhibitor for use in cancer treatment. PMID:22836184

  8. Contributions of GABA to alcohol responsivity during adolescence: Insights from preclinical and clinical studies

    PubMed Central

    Silveri, Marisa M.

    2015-01-01

    There is a considerable body of literature demonstrating that adolescence is a unique age period, which includes rapid and dramatic maturation of behavioral, cognitive, hormonal and neurobiological systems. Most notably, adolescence is also a period of unique responsiveness to alcohol effects, with both hyposensitivity and hypersensitivity observed to the various effects of alcohol. Multiple neurotransmitter systems are undergoing fine-tuning during this critical period of brain development, including those that contribute to the rewarding effects of drugs of abuse. The role of developmental maturation of the γ-amino-butyric acid (GABA) system, however, has received less attention in contributing to age-specific alcohol sensitivities. This review integrates GABA findings from human magnetic resonance spectroscopy studies as they may translate to understanding adolescent-specific responsiveness to alcohol effects. Better understanding of the vulnerability of the GABA system both during adolescent development, and in psychiatric conditions that include alcohol dependence, could point to a putative mechanism, boosting brain GABA, that may have increased effectiveness for treating alcohol abuse disorders. PMID:24631274

  9. Preclinical studies of vascular acting photosensitizer bacteriopheophorbide for the treatment of prostate cancer

    NASA Astrophysics Data System (ADS)

    Hetzel, Fred W.; Chen, Qun; Luck, David; Beckers, Jill; Huang, Zheng

    2004-06-01

    Photodynamic therapy (PDT) mediated with vascular acting photosensitizer pd-bacteriopheophorbide (Tookad), is investigated as an alternative modality for the total ablation of prostate cancer. In vivo normal canine prostate is used as the animal model. Interstitial PDT was performed by irradiating the surgically exposed prostates with a diode laser (763 nm, 150 mW/cm) to activate the IV infused photosensitizer drug. The prostate and its adjacent tissues were harvested and subjected to histopathological examination. At one-week post PDT, the animals recovered well with little or no urethral complications. Prostatic urethra and prostate adjacent tissues (bladder and underlying colon) were well preserved. PDT induced prostate lesions were characterized by marked hemorrhagic necrosis. Prostate lesions could be detected by MRI scan as early as 48 h post PDT. Maximum lesion size of 1.5 cm3 and 2.9 cm3 could be achieved at 50 J/cm and 100 J/cm, respectively, with interstitial treatment using a single 1-cm diffuser fiber, suggesting the Tookad-PDT is very effective in ablating prostatic tissue. Pharmacokinetic studies show that the photosensitizer is cleared rapidly from the circulation. In conclusion, the novel photosensitizer Tookad mediated PDT may provide an effective alternative to treat localized prostate cancer.

  10. Development of telmisartan in the therapy of spinal cord injury: pre-clinical study in rats

    PubMed Central

    Lin, Chien-Min; Tsai, Jo-Ting; Chang, Chen Kuei; Cheng, Juei-Tang; Lin, Jia-Wei

    2015-01-01

    Background Decrease of peroxisome proliferator-activated receptors-δ (PPARδ) expression has been observed after spinal cord injury (SCI). Increase of PPARδ may improve the damage in SCI. Telmisartan, the antihypertensive agent, has been mentioned to increase the expression of PPARδ. Thus, we are going to screen the effectiveness of telmisartan in SCI for the development of it in clinical application. Methods In the present study, we used compressive SCI in rats. Telmisartan was then used to evaluate the influence in rats after SCI. Change in PPARδ expression was identified by Western blots. Also, behavioral tests were performed to check the recovery of damage. Results Recovery of damage from SCI was observed in telmisartan-treated rats. Additionally, this action of telmisartan was inhibited by GSK0660 at the dose sufficient to block PPARδ. However, metformin at the dose enough to activate adenosine monophosphate-activated protein kinase failed to produce similar action as telmisartan. Thus, mediation of adenosine monophosphate-activated protein kinase in this action of telmisartan can be rule out. Moreover, telmisartan reversed the expressions of PPARδ in rats with SCI. Conclusion The obtained data suggest that telmisartan can improve the damage of SCI in rats through an increase in PPARδ expression. Thus, telmisartan is useful to be developed as an agent in the therapy of SCI. PMID:26316709

  11. The Usefulness of Systematic Reviews of Animal Experiments for the Design of Preclinical and Clinical Studies

    PubMed Central

    de Vries, Rob B. M.; Wever, Kimberley E.; Avey, Marc T.; Stephens, Martin L.; Sena, Emily S.; Leenaars, Marlies

    2014-01-01

    The question of how animal studies should be designed, conducted, and analyzed remains underexposed in societal debates on animal experimentation. This is not only a scientific but also a moral question. After all, if animal experiments are not appropriately designed, conducted, and analyzed, the results produced are unlikely to be reliable and the animals have in effect been wasted. In this article, we focus on one particular method to address this moral question, namely systematic reviews of previously performed animal experiments. We discuss how the design, conduct, and analysis of future (animal and human) experiments may be optimized through such systematic reviews. In particular, we illustrate how these reviews can help improve the methodological quality of animal experiments, make the choice of an animal model and the translation of animal data to the clinic more evidence-based, and implement the 3Rs. Moreover, we discuss which measures are being taken and which need to be taken in the future to ensure that systematic reviews will actually contribute to optimizing experimental design and thereby to meeting a necessary condition for making the use of animals in these experiments justified. PMID:25541545

  12. Silver nanoparticle/chitosan oligosaccharide/poly(vinyl alcohol) nanofibers as wound dressings: a preclinical study.

    PubMed

    Li, Chenwen; Fu, Ruoqiu; Yu, Caiping; Li, Zhuoheng; Guan, Haiyan; Hu, Daqiang; Zhao, Dehua; Lu, Laichun

    2013-01-01

    In this study, a mixture of poly(vinyl alcohol) (PVA) and chitosan oligosaccharides (COS) was electrospun with silver nanoparticles (AgNPs) to produce fibrous mats for use in wound healing. The AgNPs were reduced by COS prior to electrospinning or Ag(+) was reduced via ultraviolet irradiation in nanofibers. The morphologies of the PVA/COS/AgNO3 and PVA/COS-AgNP nanofibers were analyzed by scanning electron microscopy. Formation of the AgNPs was investigated by field emission transmission electron microscopy, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. We also evaluated the biocompatibility of the nanofibers, particularly their cytotoxicity to human skin fibroblasts and potential to cause primary skin irritation. The in vitro antibacterial activity and in vivo wound healing capacity of the nanofibers were also investigated. The nanofibers had a smooth surface with an average diameter of 130-192 nm. The diameters of the AgNPs were in the range of 15-22 nm. The nanofibers significantly inhibited growth of Escherichia coli and Staphylococcus aureus bacteria. PVA/COS-AgNP nanofibers accelerated the rate of wound healing over that of the control (gauze). The results of our in vitro and in vivo animal experiments suggest that PVA/COS-AgNP nanofibers should be of greater interest than PVA/COS/AgNO3 nanofibers for clinical use as a bioactive wound dressing. PMID:24204142

  13. Khat (Catha edulis F.) and cannabinoids: Parallel and contrasting behavioral effects in preclinical and clinical studies.

    PubMed

    Geresu, Berhanu

    2015-11-01

    After a brief outline of Catha edulis F. (khat) and the cannabinoid systems, the interactions between the pharmacological effects of khat and cannabinoids will be reviewed. Khat chewing is a widespread habit that has a deep-rooted sociocultural tradition in Africa and the Middle East. Experimental studies conducted to investigate khat's central and peripheral effects have revealed an amphetamine-like mechanism of action mediated through the dopaminergic system. The endocannabinoid system comprises the receptors, the endogenous agonists and the related biochemical machinery responsible for synthesizing these substances and terminating their actions. Endocannabinoids are synthesized "on demand" from membrane phospholipids and then rapidly cleared by cellular uptake and enzymatic degradation. Khat and cannabinoids produce a body of parallel and contrasting behavioral effects. Concurrent consumption of khat and cannabinoids may increase the risk of getting or precipitating psychosis, has rewarding and motivational effect, increases the threshold of pain perception and impairs learning and memory. On the other hand, the action of cannabis to enhance food intake is likely to reduce khat's appetite suppressant effects. PMID:26469212

  14. Reduction in muscular motility by selective focused cold therapy: a preclinical study.

    PubMed

    Hsu, Michael; Stevenson, Fang-Feng

    2014-01-01

    Application of freezing temperatures to the temporal branch of the facial nerve can temporarily inhibit motor nerve conduction, resulting in inhibition of voluntary contraction of the frontalis and glabella muscle groups. This feasibility study demonstrates the reduction in motility of muscle groups through application of low temperatures to nerves in a rat model. Twenty-seven adult female Sprague-Dawley rats received cryotreatment to the tibial nerve of the hind limb, and the contralateral limb was left untreated as a negative control. The use of a cold temperature application (-59 ± 8 °C for 60 s) onto the rat tibial nerve resulted in temporary reduction of physiological function of the hind limb. Histological observations of the nerve revealed demyelination and axonal degeneration by 2 weeks post-treatment followed by complete axonal regeneration and remyelination at 16 weeks. Application of low temperatures to peripheral motor nerves resulted in temporary denervation and loss of function of the treated hind limb. Low temperature treatment on motor nerves did not result in any permanent or long-term changes to function and structure of the nerves. PMID:23917804

  15. Use of electrogastrography in preclinical studies of cholinergic and anticholinergic agents in experimental pigs.

    PubMed

    Květina, J; Tachecí, I; Pavlík, M; Kopáčová, M; Rejchrt, S; Douda, T; Kuneš, M; Bureš, J

    2016-01-01

    Electrogastrography (EGG) is a non-invasive method for the assessment of gastric myoelectrical activity. Porcine EGG is comparable with human one. The purpose of this study was to evaluate the effect of atropine and neostigmine on the EGG in experimental pigs. Adult female pigs were administrated atropine (1.5 mg i.m., n=6) and neostigmine (0.5 mg i.m., n=6) after the baseline EGG, followed by a 90-min trial recording (MMS, Enschede, the Netherlands). Running spectral analysis was used for the evaluation. The results were expressed as dominant frequency of slow waves and EGG power (areas of amplitudes). Neostigmine increased continuously the dominant frequency and decreased significantly the EGG power. Atropine did not change the dominant frequency significantly. However, atropine increased significantly the EGG power (areas of amplitudes) from basal values to the maximum at the 10-20-min interval. After that period, the areas of amplitudes decreased significantly to the lowest values at the 60-90-min interval. In conclusion, cholinergic and anticholinergic agents affect differently EGG in experimental pigs. PMID:26674291

  16. Preclinical Studies on Neurobehavioral and Neuromuscular Effects of Cocaine Hydrolase Gene Therapy in Mice

    PubMed Central

    Murthy, Vishakantha; Gao, Yang; Geng, Liyi; LeBrasseur, Nathan; White, Thomas; Brimijoin, Stephen

    2014-01-01

    Cocaine hydrolase gene transfer of mutated human butyrylcholinesterase (BChE) is evolving as a promising therapy for cocaine addiction. BChE levels after gene transfer can be 1,500-fold above those in untreated mice, making this enzyme the second most abundant plasma protein. Because mutated BChE is approximately 70 % as efficient in hydro-lyzing acetylcholine as wild-type enzyme, it is important to examine the impact on cholinergic function. Here, we focused on memory and cognition (Stone T-maze), basic neuromuscular function (treadmill endurance and grip strength), and coordination (Rotarod). BALB/c mice were given adeno-associated virus vector or helper-dependent adenoviral vector encoding mouse or human BChE optimized for cocaine. Age-matched controls received saline or luciferase vector. Despite high doses (up to 1013 particles per mouse) and high transgene expression (1,000-fold above baseline), no deleterious effects of vector treatment were seen in neurobehavioral functions. The vector-treated mice performed as saline-treated and lucif-erase controls in maze studies and strength tests, and their Rotarod and treadmill performance decreased less with age. Thus, neither the viral vectors nor the large excess of BChE caused observable toxic effects on the motor and cognitive systems investigated. This outcome justifies further steps toward an eventual clinical trial of vector-based gene transfer for cocaine abuse. PMID:24085526

  17. A 3-week pre-clinical study of 2?-fucosyllactose in farm piglets.

    PubMed

    Hanlon, Paul R; Thorsrud, Bjorn A

    2014-12-01

    One of the most abundant oligosaccharides found in human milk is 2?-fucosyllactose, a trisaccharide composed of fucose and lactose, and multiple studies have demonstrated a health benefit to this compound. Recent advances have allowed for the large-scale production of oligosaccharides via fermentation, including 2?-fucosyllactose. A neonatal piglet model was used to evaluate the tolerability of 2?-fucosyllactose, produced through this process, in order to demonstrate the suitability of this compound for human infants under 12 weeks of age. Crossbred farm piglets, at lactation day 2, were assigned to one of four treatment groups receiving a liquid diet containing 0, 200, 500 or 2000?mg/L of 2?-fucosyllactose. The calculated consumption of 2?-fucosyllactose corresponded to dose levels of 29.37, 72.22 and 291.74?mg/kg/day, respectively, in males and 29.30, 74.31, and 298.99?mg/kg/day, respectively in females. Piglets were administered diet for 3 weeks; and there were no test article-related effects on growth and development (clinical observations, body weight and food consumption), clinical pathology parameters (hematology, clinical chemistry, coagulation and urinalysis), or any histopathologic changes. Therefore, dietary exposure to 2?-fucosyllactose at concentrations up to 2000?mg/L was well tolerated by neonatal farm piglets and did not result in adverse health effects or impact piglet growth. PMID:25445760

  18. High-throughput monitoring of integration site clonality in preclinical and clinical gene therapy studies

    PubMed Central

    Giordano, Frank A; Appelt, Jens-Uwe; Link, Barbara; Gerdes, Sebastian; Lehrer, Christina; Scholz, Simone; Paruzynski, Anna; Roeder, Ingo; Wenz, Frederik; Glimm, Hanno; von Kalle, Christof; Grez, Manuel; Schmidt, Manfred; Laufs, Stephanie

    2015-01-01

    Gene transfer to hematopoietic stem cells with integrating vectors not only allows sustained correction of monogenic diseases but also tracking of individual clones in vivo. Quantitative real-time PCR (qPCR) has been shown to be an accurate method to quantify individual stem cell clones, yet due to frequently limited amounts of target material (especially in clinical studies), it is not useful for large-scale analyses. To explore whether vector integration site (IS) recovery techniques may be suitable to describe clonal contributions if combined with next-generation sequencing techniques, we designed artificial ISs of different sizes which were mixed to simulate defined clonal situations in clinical settings. We subjected all mixes to either linear amplification–mediated PCR (LAM-PCR) or nonrestrictive LAM-PCR (nrLAM-PCR), both combined with 454 sequencing. We showed that nrLAM-PCR/454-detected clonality allows estimating qPCR-detected clonality in vitro. We then followed the kinetics of two clones detected in a patient enrolled in a clinical gene therapy trial using both, nrLAM-PCR/454 and qPCR and also saw nrLAM-PCR/454 to correlate to qPCR-measured clonal contributions. The method presented here displays a feasible high-throughput strategy to monitor clonality in clinical gene therapy trials is at hand. PMID:26052530

  19. Silver nanoparticle/chitosan oligosaccharide/poly(vinyl alcohol) nanofibers as wound dressings: a preclinical study

    PubMed Central

    Li, Chenwen; Fu, Ruoqiu; Yu, Caiping; Li, Zhuoheng; Guan, Haiyan; Hu, Daqiang; Zhao, Dehua; Lu, Laichun

    2013-01-01

    In this study, a mixture of poly(vinyl alcohol) (PVA) and chitosan oligosaccharides (COS) was electrospun with silver nanoparticles (AgNPs) to produce fibrous mats for use in wound healing. The AgNPs were reduced by COS prior to electrospinning or Ag+ was reduced via ultraviolet irradiation in nanofibers. The morphologies of the PVA/COS/AgNO3 and PVA/COS-AgNP nanofibers were analyzed by scanning electron microscopy. Formation of the AgNPs was investigated by field emission transmission electron microscopy, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. We also evaluated the biocompatibility of the nanofibers, particularly their cytotoxicity to human skin fibroblasts and potential to cause primary skin irritation. The in vitro antibacterial activity and in vivo wound healing capacity of the nanofibers were also investigated. The nanofibers had a smooth surface with an average diameter of 130–192 nm. The diameters of the AgNPs were in the range of 15–22 nm. The nanofibers significantly inhibited growth of Escherichia coli and Staphylococcus aureus bacteria. PVA/COS-AgNP nanofibers accelerated the rate of wound healing over that of the control (gauze). The results of our in vitro and in vivo animal experiments suggest that PVA/COS-AgNP nanofibers should be of greater interest than PVA/COS/AgNO3 nanofibers for clinical use as a bioactive wound dressing. PMID:24204142

  20. Photoacoustic spectroscopy in the monitoring of breast tumor development: a pre-clinical study

    NASA Astrophysics Data System (ADS)

    Priya, Mallika; Rao, Bola Sadashiva Satish; Ray, Satadru; Mahato, Krishna Kishore

    2014-03-01

    Breast cancer is the most frequently diagnosed cancer type and its detection at an early stage can reduce the mortality rate substantially. With the aim to detect breast cancer early, by studying tumor progression in nude mice, a pulsed laser induced photoacoustic spectroscopy set up has been designed and developed. MCF-7 cells xenografts were developed using six to eight weeks old female nude mice and tumor tissues were extracted on different days (10th, 15th and 20th Day) post injection and the corresponding photoacoustic spectra were recorded at 281nm excitation. A total of 144 time domain spectra were recorded from 36 animals belonging to the three time points (10th, 15th and 20th day post injection) and converted into frequency domains by Fast Fourier Transform (FFT) tools of the MATLAB algorithms and analyzed. The frequency patterns of the tumor masses on 10th, 15th and 20th day of tumor development showed a gradual increase in intensity at certain frequencies, 5.93 x103 Hz, 15.9 x103 Hz, 29.69 x103 Hz and 32.5 x103 Hz in the FFT patterns indicating that these frequencies were more sensitive towards tumor development. Further analysis of the data yielded a clear variation in the spectral parameters with progression of the disease suggesting that the technique may be suitable for early detection of the disease. Thus, we expect that the developed setup may be useful in assessing the different phases of tumor development which may have clinical implications.

  1. Molecular actions and therapeutic potential of lithium in preclinical and clinical studies of CNS disorders

    PubMed Central

    Chiu, Chi-Tso; Chuang, De-Maw

    2011-01-01

    Lithium has been used clinically to treat bipolar disorder for over half a century, and remains a fundamental pharmacological therapy for patients with this illness. Although lithium’s therapeutic mechanisms are not fully understood, substantial in vitro and in vivo evidence suggests that it has neuroprotective/neurotrophic properties against various insults, and considerable clinical potential for the treatment of several neurodegenerative conditions. Evidence from pharmacological and gene manipulation studies support the notion that glycogen synthase kinase-3 inhibition and induction of brain-derived neurotrophic factor-mediated signaling are lithium’s main mechanisms of action, leading to enhanced cell survival pathways and alteration of a wide variety of downstream effectors. By inhibiting N-methyl-D-aspartate receptor-mediated calcium influx, lithium also contributes to calcium homeostasis and suppresses calcium-dependent activation of pro-apoptotic signaling pathways. In addition, lithium decreases inositol 1,4,5-trisphosphate by inhibiting phosphoinositol phosphatases, a process recently identified as a novel mechanism for inducing autophagy. Through these mechanisms, therapeutic doses of lithium have been demonstrated to defend neuronal cells against diverse forms of death insults and to improve behavioral as well as cognitive deficits in various animal models of neurodegenerative diseases, including stroke, amyotrophic lateral sclerosis, fragile X syndrome, as well as Huntington’s, Alzheimer’s, and Parkinson’s diseases, among others. Several clinical trials are also underway to assess the therapeutic effects of lithium for treating these disorders. This article reviews the most recent findings regarding the potential targets involved in lithium’s neuroprotective effects, and the implication of these findings for the treatment of a variety of diseases. PMID:20705090

  2. Microrobotized blasting improves the bone-to-textured implant response. A preclinical in vivo biomechanical study.

    PubMed

    Coelho, Paulo G; Gil, Luiz F; Neiva, Rodrigo; Jimbo, Ryo; Tovar, Nick; Lilin, Thomas; Bonfante, Estevam A

    2016-03-01

    This study evaluated the effect of microrobotized blasting of titanium endosteal implants relative to their manually blasted counterparts. Two different implant systems were utilized presenting two different implant surfaces. Control surfaces (Manual) were fabricated by manually grit blasting the implant surfaces while experimental surfaces (Microblasted) were fabricated through a microrobotized system that provided a one pass grit blasting routine. Both surfaces were created with the same ~50µm average particle size alumina powder at ~310KPa. Surfaces were then etched with 37% HCl for 20min, washed, and packaged through standard industry procedures. The surfaces were characterized through scanning electron microscopy (SEM) and optical interferometry, and were then placed in a beagle dog radius model remaining in vivo for 3 and 6 weeks. The implant removal torque was recorded and statistical analysis evaluated implant system and surface type torque levels as a function of time in vivo. Histologic sections were qualitatively evaluated for tissue response. Electron microscopy depicted textured surfaces for both manual and microblasted surfaces. Optical interferometry showed significantly higher Sa, Sq, values for the microblasted surface and no significant difference for Sds and Sdr values between surfaces. In vivo results depicted that statistically significant gains in biomechanical fixation were obtained for both implant systems tested at 6 weeks in vivo, while only one system presented significant biomechanical gain at 3 weeks. Histologic sections showed qualitative higher amounts of new bone forming around microblasted implants relative to the manually blasted group. Microrobotized blasting resulted in higher biomechanical fixation of endosteal dental implants and should be considered as an alternative for impant surface manufacturing. PMID:26703231

  3. Preclinical immunogenicity study of trivalent meningococcal AWX-OMV vaccines for the African meningitis belt.

    PubMed

    Tunheim, G; Naess, L M; Acevedo, R; Fjeldheim, Å K; Bolstad, K; García, L; Cardoso, D; Aase, A; Zayas, C; González, H; Rosenqvist, E; Norheim, G

    2014-11-20

    In the recent decade, epidemic meningitis in the African meningitis belt has mostly been caused by Neisseria meningitidis of serogroups A, W and X (MenA, MenW and MenX, respectively). There is at present no licensed vaccine available to prevent MenX meningococcal disease. To explore a trivalent MenAWX vaccine concept, we have studied the immunogenicity in mice of MenX outer membrane vesicles (X-OMV) or MenX polysaccharide (X-PS) when combined with a bivalent A-OMV and W-OMV (AW-OMV) vaccine previously shown to be highly immunogenic in mice. The vaccine antigens were produced from three representative wild type strains of MenA (ST-7), MenW (ST-11) and MenX (ST-751) isolated from patients in the African meningitis belt. Groups of mice were immunized with two doses of X-OMV or X-PS combined with the AW-OMV vaccine or as individual components. All vaccine preparations were adsorbed to Al(OH)3. Sera from immunized mice were tested by ELISA and immunoblotting. Functional antibody responses were measured as serum bactericidal activity (SBA) and opsonophagocytic activity (OPA). Immunization of mice with X-OMV, alone or in combination with AW-OMV induced high levels of anti-X OMV IgG. Moreover, X-OMV alone or in combination with the AW-OMV vaccine induced high SBA and OPA titers against the MenX target strain. X-PS alone was not immunogenic in mice; however, addition of the AW-OMV vaccine to X-PS increased the immunogenicity of X-PS. Both AWX vaccine formulations induced high levels of IgG against A- and W-OMV and high SBA titers against the MenA and MenW vaccine strains. These results suggest that a trivalent AWX vaccine, either as a combination of OMV or OMV with X-PS, could potentially prevent the majority of meningococcal disease in the meningitis belt. PMID:25305564

  4. Fiber optic fluorescence detection of low-level porphyrin concentrations in preclinical and clinical studies

    NASA Astrophysics Data System (ADS)

    Mang, Thomas S.; McGinnis, Carolyn; Khan, S.

    1990-07-01

    A significant clinical problem in the local treatment of cutaneous metastases of breast cancer (by any modality--surgery, radiation therapy or photodynainic therapy) is the fact that the disease almost always extends beyond the boundary of visible lesions in the form of microscopic deposits. These deposits may be distant from the site of visible disease but are often in close proximity to it and are manifested sooner or later by the development of recurrent lesions at the border of the treated area, thus the "marginal miss" in radiation therapy, the "rim recurrence" in photodynamic therapy, and the "incisional recurrence" following surgical excision. More intelligent use of these treatment modalities demands the ability to detect microscopic deposits of tumor cells using non-invasive methodology. In vivo fluorescence measurements have been made possible by the development of an extremely sensitive fiber optic in vivo fluorescence photometer. The instrument has been used to verify that fluorescence correlated with injected porphyrin levels in various tissues. The delivery of light to excite and detect background fluorescence as well as photosensitizer fluorescence in tissues has been accomplished using two HeNe lasers emitting at 632.8 nm and 612 nm delivered through a single quartz fiber optic. Chopping at different frequencies, contributions of fluorescence may be separated. Fluorescence is picked up via a 400 micron quartz fiber optic positioned appropriately near the target tissue. Validation of these levels was made by extraction of the drug from the tissues with resultant quantitation. Recently, an extensive study was undertaken to determine if fluorescence could be used for the detection of occult, clinically non-palpable metastases in the lymph node of rats. This unique model allowed for the detection of micrometastases in lymph nodes using very low injected doses of the photosensitizer Photofrin II. Data obtained revealed the ability to detect on the order of 50-100 cells using 0.25 mg/kg of sensitizer, a level 20 times lower than normally used for treatment of animal tumors. These results indicate that Photofrin II could be used for fluorescence detection of small metastatic tumors, while substantially reducing the major side effect of PDT; namely, prolonged photosensitivity. Results to be presented demonstrate the ability of this technique to detect microscopic deposits of malignant tumor cells in patients with metastatic breast cancer. These deposits were found in clinically negative areas of the chest wall.

  5. Bone metastasis imaging with SPECT/CT/MRI: a preclinical toolbox for therapy studies.

    PubMed

    Sanches, Pedro Gomes; Peters, Steffie; Rossin, Raffaella; Kaijzel, Eric L; Que, Ivo; Lwik, Clemens W G M; Grll, Holger

    2015-06-01

    Bone is one of the most common metastatic target sites in breast cancer, with more than 200 thousand new cases of invasive cancer diagnosed in the US alone in 2011. We set out to establish a multimodality imaging platform for bone metastases in small animals as a tool to non-invasively quantify metastasis growth, imaging the ensuing bone lesions and possibly the response to treatment. To this end, a mouse model of osteolytic metastatic bone tumors was characterized with SPECT/CT and MRI over time. A cell line capable of forming bone metastases, MDA-MB-231, was genetically modified to stably express the reporter gene herpes simplex virus-1 thymidine kinase (hsv-1 tk). The intracellular accumulation of the radiolabeled tracer [(123)I]FIAU promoted by HSV-1 TK specifically pinpoints the location of tumor cells which can be imaged in vivo by SPECT. First, a study using tumors implanted subcutaneously was performed. The SPECT/MRI overlays and the ex vivo ?-counting showed a linear correlation in terms of %ID/cm(3) (R(2)=0.93) and %ID/g (R(2)=0.77), respectively. Then, bone metastasis growth was imaged weekly by SPECT/CT and T2-weighted MRI over a maximum of 40 days post-intracardiac injection of tumor cells. The first activity spots detectable with SPECT, around day 20 post-cell injection, were smaller than 2mm(3) and not yet visible by MRI and increased in volume and in %ID over the weeks. Osteolytic bone lesions were visible by CT (in vivo) and ?CT (ex vivo). The SPECT/MRI overlays also showed a linear correlation in terms of %ID/cm(3) (R(2)=0.86). In conclusion, a new multimodality imaging platform has been established that non-invasively combines images of active tumor areas (SPECT), tumor volume (MRI) and the corresponding bone lesions (CT and ?CT). To our knowledge this is the first report where the combination of soft tissue information from MRI, bone lesions by CT, and reporter gene imaging by SPECT is used to non-invasively follow metastatic bone lesions. PMID:25680341

  6. [Application of pre-clinical PET imaging for drug development].

    PubMed

    Tsukada, Hideo

    2011-11-01

    Positron emission tomography (PET) is a sophisticated method for the quantitative and noninvasive imaging of biological functions by monitoring the delivery of tracers labeled with positron emitters (1C, 'aN, '"O, and 8F). The distribution and kinetic patterns of a labeled compound in relation to the specific biomolecule in the target tissue are assumed to reflect specific biological functions in the living body. A wide variety of labeled compounds as molecular probes have been developed to measure biochemical and physiological parameters, such as blood flow, glucose and oxygen metabolism, protein synthesis, and neurotransmitter receptor functions. Recently, PET has gradually been introduced into the research field of drug development both in pre-clinical and clinical stages. In the present chapter, the applications of animal PET with small animals (rats and mice) and non-human primates in drug development in the pre-clinical stage will be discussed based on our own experiences. In the course of drug development, the pre-clinical studies with experimental animals are indispensable, and these studies are expected to provide useful information to facilitate the development of drug candidates with more efficacy and fewer adverse effects in the clinical stage with PMID:22256612

  7. Sources of Self-Efficacy in Mathematics: A Validation Study

    ERIC Educational Resources Information Center

    Usher, Ellen L.; Pajares, Frank

    2009-01-01

    The purpose of this study was to develop and validate items with which to assess A. Bandura's (1997) theorized sources of self-efficacy among middle school mathematics students. Results from Phase 1 (N=1111) were used to develop and refine items for subsequent use. In Phase 2 of the study (N=824), a 39-item, four-factor exploratory model fit best.

  8. A Cre-conditional MYCN-driven neuroblastoma mouse model as an improved tool for preclinical studies

    PubMed Central

    Althoff, K; Beckers, A; Bell, E; Nortmeyer, M; Thor, T; Sprssel, A; Lindner, S; De Preter, K; Florin, A; Heukamp, L C; Klein-Hitpass, L; Astrahantseff, K; Kumps, C; Speleman, F; Eggert, A; Westermann, F; Schramm, A; Schulte, J H

    2015-01-01

    Neuroblastoma, a childhood cancer that originates from neural crest-derived cells, is the most common deadly solid tumor of infancy. Amplification of the MYCN oncogene, which occurs in approximately 2025% of human neuroblastomas, is the most prominent genetic marker of high-stage disease. The availability of valid preclinical in vivo models is a prerequisite to develop novel targeted therapies. We here report on the generation of transgenic mice with Cre-conditional induction of MYCN in dopamine ?-hydroxylase-expressing cells, termed LSL-MYCN;Dbh-iCre. These mice develop neuroblastic tumors with an incidence of >75%, regardless of strain background. Molecular profiling of tumors revealed upregulation of the MYCN-dependent miR-1792 cluster as well as expression of neuroblastoma marker genes, including tyrosine hydroxylase and the neural cell adhesion molecule 1. Gene set enrichment analyses demonstrated significant correlation with MYC-associated expression patterns. Array comparative genome hybridization showed that chromosomal aberrations in LSL-MYCN;Dbh-iCre tumors were syntenic to those observed in human neuroblastomas. Treatment of a cell line established from a tumor derived from a LSL-MYCN;Dbh-iCre mouse with JQ1 or MLN8237 reduced cell viability and demonstrated oncogene addiction to MYCN. Here we report establishment of the first Cre-conditional human MYCN-driven mouse model for neuroblastoma that closely recapitulates the human disease with respect to tumor localization, histology, marker expression and genomic make up. This mouse model is a valuable tool for further functional studies and to assess the effect of targeted therapies. PMID:25174395

  9. The prevalence and correlations of medical student burnout in the pre-clinical years: a cross-sectional study.

    PubMed

    Mazurkiewicz, Rebecca; Korenstein, Deborah; Fallar, Robert; Ripp, Jonathan

    2012-01-01

    Burnout is a psychological syndrome of emotional exhaustion, depersonalization, and impaired personal accomplishment induced by repeated workplace stressors. Current research suggests that physician burnout may have its origins in medical school. The consequences of medical student burnout include both personal and professional distress, loss of empathy, and poor health. We hypothesized that burnout occurs prior to the initiation of the clinical years of medical education. This was a cross-sectional survey administered to third-year medical students at the Mount Sinai School of Medicine (MSSM) in New York, New York (a traditional-style medical school with a marked division between pre-clinical and clinical training occurring at the beginning of the third year). Survey included an instrument used to measure job burnout, a sleep deprivation screen, and questions related to demographic information, current rotation, psychiatric history, time spent working/studying, participation in extracurricular activities, social support network, autonomy and isolation. Of the 86 medical students who participated, 71% met criteria for burnout. Burnt out students were significantly more likely to suffer from sleep deprivation (p=0.0359). They were also more likely to disagree with the following statements: "I have control over my daily schedule" (p=0.0286) and "I am confident that I will have the knowledge and skills necessary to become an intern when I graduate" (p=0.0263). Our findings show that burnout is present at the beginning of the third year of medical school, prior to the initiation of the clinical years of medical training. Medical student burnout is quite common, and early efforts should be made to empower medical students to both build the knowledge and skills necessary to become capable physicians, as well as withstand the emotional, mental, and physical challenges inherent to medical school. PMID:21781020

  10. Monte Carlo simulation on pre-clinical irradiation: A heterogeneous phantom study on monoenergetic kilovoltage photon beams

    NASA Astrophysics Data System (ADS)

    Chow, James C. L.

    2012-10-01

    This study investigated radiation dose variations in pre-clinical irradiation due to the photon beam energy and presence of tissue heterogeneity. Based on the same mouse computed tomography image dataset, three phantoms namely, heterogeneous, homogeneous and bone homogeneous were used. These phantoms were generated by overriding the relative electron density of no voxel (heterogeneous), all voxel (homogeneous) and the bone voxel (bone homogeneous) to one. 360 photon arcs with beam energies of 50 - 1250 keV were used in mouse irradiations. Doses in the above phantoms were calculated using the EGSnrc-based DOSXYZnrc code through the DOSCTP. Monte Carlo simulations were carried out in parallel using multiple nodes in a high-performance computing cluster. It was found that the dose conformity increased with the increase of the photon beam energy from the keV to MeV range. For the heterogeneous mouse phantom, increasing the photon beam energy from 50 keV to 1250 keV increased seven times the dose deposited at the isocenter. For the bone dose enhancement, the mean dose was 2.7 times higher when the bone heterogeneity was not neglected using the 50 keV photon beams in the mouse irradiation. Bone dose enhancement affecting the mean dose was found in the photon beams with energy range of 50 - 200 keV and the dose enhancement decreased with an increase of the beam energy. Moreover, the MeV photon beam had a higher dose at the isocenter, and a better dose conformity compared to the keV beam.

  11. A Cre-conditional MYCN-driven neuroblastoma mouse model as an improved tool for preclinical studies.

    PubMed

    Althoff, K; Beckers, A; Bell, E; Nortmeyer, M; Thor, T; Sprüssel, A; Lindner, S; De Preter, K; Florin, A; Heukamp, L C; Klein-Hitpass, L; Astrahantseff, K; Kumps, C; Speleman, F; Eggert, A; Westermann, F; Schramm, A; Schulte, J H

    2015-06-01

    Neuroblastoma, a childhood cancer that originates from neural crest-derived cells, is the most common deadly solid tumor of infancy. Amplification of the MYCN oncogene, which occurs in approximately 20-25% of human neuroblastomas, is the most prominent genetic marker of high-stage disease. The availability of valid preclinical in vivo models is a prerequisite to develop novel targeted therapies. We here report on the generation of transgenic mice with Cre-conditional induction of MYCN in dopamine β-hydroxylase-expressing cells, termed LSL-MYCN;Dbh-iCre. These mice develop neuroblastic tumors with an incidence of >75%, regardless of strain background. Molecular profiling of tumors revealed upregulation of the MYCN-dependent miR-17-92 cluster as well as expression of neuroblastoma marker genes, including tyrosine hydroxylase and the neural cell adhesion molecule 1. Gene set enrichment analyses demonstrated significant correlation with MYC-associated expression patterns. Array comparative genome hybridization showed that chromosomal aberrations in LSL-MYCN;Dbh-iCre tumors were syntenic to those observed in human neuroblastomas. Treatment of a cell line established from a tumor derived from a LSL-MYCN;Dbh-iCre mouse with JQ1 or MLN8237 reduced cell viability and demonstrated oncogene addiction to MYCN. Here we report establishment of the first Cre-conditional human MYCN-driven mouse model for neuroblastoma that closely recapitulates the human disease with respect to tumor localization, histology, marker expression and genomic make up. This mouse model is a valuable tool for further functional studies and to assess the effect of targeted therapies. PMID:25174395

  12. Efficacy and mechanism of action of the tyrosine kinase inhibitors gefitinib, lapatinib and neratinib in the treatment of HER2-positive breast cancer: preclinical and clinical evidence

    PubMed Central

    Segovia-Mendoza, Mariana; Gonzlez-Gonzlez, Mara E; Barrera, David; Daz, Lorenza; Garca-Becerra, Roco

    2015-01-01

    An increasing number of tumors, including breast cancer, overexpress proteins of the epidermal growth factor receptor (EGFR) family. The interaction between family members activates signaling pathways that promote tumor progression and resistance to treatment. Human epidermal growth factor receptor type II (HER2) positive breast cancer represents a clinical challenge for current therapy. It has motivated the development of novel and more effective therapeutic EGFR family target drugs, such as tyrosine kinase inhibitors (TKIs). This review focuses on the effects of three TKIs mostly studied in HER2- positive breast cancer, lapatinib, gefitinib and neratinib. Herein, we discuss the mechanism of action, therapeutic advantages and clinical applications of these TKIs. To date, TKIs seem to be promising therapeutic agents for the treatment of HER2-overexpressing breast tumors, either as monotherapy or combined with other pharmacological agents. PMID:26609467

  13. Efficacy and mechanism of action of the tyrosine kinase inhibitors gefitinib, lapatinib and neratinib in the treatment of HER2-positive breast cancer: preclinical and clinical evidence.

    PubMed

    Segovia-Mendoza, Mariana; Gonzlez-Gonzlez, Mara E; Barrera, David; Daz, Lorenza; Garca-Becerra, Roco

    2015-01-01

    An increasing number of tumors, including breast cancer, overexpress proteins of the epidermal growth factor receptor (EGFR) family. The interaction between family members activates signaling pathways that promote tumor progression and resistance to treatment. Human epidermal growth factor receptor type II (HER2) positive breast cancer represents a clinical challenge for current therapy. It has motivated the development of novel and more effective therapeutic EGFR family target drugs, such as tyrosine kinase inhibitors (TKIs). This review focuses on the effects of three TKIs mostly studied in HER2- positive breast cancer, lapatinib, gefitinib and neratinib. Herein, we discuss the mechanism of action, therapeutic advantages and clinical applications of these TKIs. To date, TKIs seem to be promising therapeutic agents for the treatment of HER2-overexpressing breast tumors, either as monotherapy or combined with other pharmacological agents. PMID:26609467

  14. Racer efficacy study - Bixby, Fall 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed competition is a primary concern for conventional and organic vegetable producers. Racer (ammonium nonanoate) is labeled for non-food use and efforts are currently underway to label it as a bio-herbicide for organically grown food crops. The objective of this study was to investigate differen...

  15. Studies on the Efficacy of Child Psychoanalysis.

    ERIC Educational Resources Information Center

    Fonagy, Peter; Moran, George S.

    1990-01-01

    Summarizes three studies on psychoanalytic psychotherapeutic treatment of diabetic children and adolescents with grossly abnormal blood glucose profiles necessitating repeated admissions to hospital. Used time series analysis, comparative analysis, and single-case experimental design to illustrate effectiveness of psychotherapeutic intervention

  16. 21 CFR 201.200 - Disclosure of drug efficacy study evaluations in labeling and advertising.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Disclosure of drug efficacy study evaluations in... Efficacy Study 201.200 Disclosure of drug efficacy study evaluations in labeling and advertising. (a)(1) The National Academy of SciencesNational Research Council, Drug Efficacy Study Group, has...

  17. The effects of granulocyte colony-stimulating factor in preclinical models of infection and acute inflammation.

    PubMed

    Marshall, John C

    2005-12-01

    The cytokine granulocyte colony-stimulating factor (G-CSF) is a potent endogenous trigger for the release of neutrophils from bone marrow stores and for their activation for enhanced antimicrobial activity. G-CSF has been widely evaluated in preclinical models of acute illness, with generally promising though divergent results. A recombinant G-CSF molecule has recently undergone clinical trials to assess its efficacy as an adjuvant therapy in community-acquired and nosocomial pneumonia, however, these studies failed to provide convincing evidence of benefit. We undertook a systematic review of the published literature reporting the effects of modulation of G-CSF in preclinical in vivo models to determine whether evidence of differential efficacy might explain the disappointing results of human studies and point to disease states that might be more likely to benefit from G-CSF therapy. G-CSF has been evaluated in 86 such studies involving a variety of different models. The strongest evidence of benefit was seen in studies involving intraperitoneal challenge with live organisms; benefit was evident whether the agent was given before or after challenge. G-CSF demonstrates anti-inflammatory activity in models of systemic challenge with viable organisms or endotoxin, but only when the agent is given before challenge; evidence of benefit after challenge was minimal. Preclinical models of intrapulmonary challenge only show efficacy when the cytokine is administered before the infectious challenge, and suggested harm in gram-negative pneumonia resulting from challenge with Escherichia coli or Klebsiella. There is little evidence for therapeutic efficacy in noninfectious models of acute illness. We conclude that the most promising populations for evaluation of G-CSF are neutropenic patients with invasive infection and patients with intra-abdominal infection, particularly those with the syndrome of tertiary, or recurrent, peritonitis. Significant variability in the design and reporting of studies of preclinical models of acute illness precludes more sophisticated data synthesis. PMID:16374383

  18. The Efficacy of Math Coaching: An Evaluative Case Study

    ERIC Educational Resources Information Center

    Dobbins, C. Neelie

    2010-01-01

    There is a lack of implementation of instructional strategies to assist middle school teachers in improving mathematics education for their students. Coaching is one solution to this problem, but its impact on student achievement is unclear. This case study evaluated the relationship between coaching and teacher efficacy and the impact of these

  19. Self-Efficacy and IPS: An Empirical Study

    ERIC Educational Resources Information Center

    McLeod, Linda P.

    2015-01-01

    The fact that some learners learn language more successfully than others who are at the same level of aptitude and capabilities is inevitable. To understand why, the researcher has focused her attention on individual differences among learners. The ones that have been taken into account in this study are namely called self-efficacy and identity…

  20. Year 3 ASK/FOSS Efficacy Study. CRESST Report 782

    ERIC Educational Resources Information Center

    Osmundson, Ellen; Dai, Yunyun; Herman, Joan

    2011-01-01

    This efficacy study was designed to examine the traditional FOSS curriculum (Delta Publishing, Full Option Science System/FOSS, magnetism and electricity, structures of life, and water modules, 2005), and the new ASK/FOSS curriculum (magnetism and electricity, structures of life, and water modules, 2005), a revised version of the original FOSS…

  1. The Efficacy of Self-Paced Study in Multitrial Learning

    ERIC Educational Resources Information Center

    de Jonge, Mario; Tabbers, Huib K.; Pecher, Diane; Jang, Yoonhee; Zeelenberg, Ren

    2015-01-01

    In 2 experiments we investigated the efficacy of self-paced study in multitrial learning. In Experiment 1, native speakers of English studied lists of Dutch-English word pairs under 1 of 4 imposed fixed presentation rate conditions (24 1 s, 12 2 s, 6 4 s, or 3 8 s) and a self-paced study condition. Total study time per list was equated for

  2. Preclinical Studies of the Potent and Selective Nicotinic α4β2 Receptor Ligand VMY-2-95

    PubMed Central

    2015-01-01

    The discovery and development of small molecules that antagonize neuronal nicotinic acetylcholine receptors may provide new ligands for evaluation in models of depression or addiction. We discovered a small molecule, VMY-2-95, a nAChR ligand with picomolar affinity and high selectivity for α4β2 receptors. In this study, we investigated its preclinical profile in regards to solubility, lipophilicity, metabolic stability, intestinal permeability, bioavailability, and drug delivery to the rat brain. Metabolic stability of VMY-2-95·2HCl was monitored on human liver microsomes, and specific activity of VMY-2-95·2HCl on substrate metabolism by CYP1A2, 2C9, 2C19, 2D6, and 3A4 was tested in a high-throughput manner. The intestinal transport of VMY-2-95·2HCl was studied through Caco-2 cell monolayer permeability. VMY-2-95·2HCl was soluble in water and chemically stable, and the apparent partition coefficient was 0.682. VMY-2-95·2HCl showed significant inhibition of CYP2C9 and 2C19, but weak or no effect on 1A2, 2D6, and 3A4. The Caco-2 cell model studies revealed that VMY-2-95·2HCl was highly permeable with efflux ratio of 1.11. VMY-2-95·2HCl achieved a maximum serum concentration of 0.56 mg/mL at 0.9 h and was orally available with a half-life of ∼9 h. Furthermore, VMY-2-95·2HCl was detected in the rat brain after 3 mg/kg oral administration and achieved a maximal brain tissue concentration of 2.3 μg/g within 60 min. Overall, the results demonstrate that VMY-2-95·2HCl has good drug like properties and can penetrate the blood–brain barrier with oral administration. PMID:25533629

  3. Sources of Self-Efficacy in Mathematics: A Validation Study

    ERIC Educational Resources Information Center

    Usher, Ellen L.; Pajares, Frank

    2009-01-01

    The purpose of this study was to develop and validate items with which to assess A. Bandura's (1997) theorized sources of self-efficacy among middle school mathematics students. Results from Phase 1 (N=1111) were used to develop and refine items for subsequent use. In Phase 2 of the study (N=824), a 39-item, four-factor exploratory model fit best.…

  4. Efficacy of the specific endothelin a receptor antagonist zibotentan (ZD4054) in colorectal cancer: a preclinical study.

    PubMed

    Haque, Samer-ul; Dashwood, Michael R; Heetun, Mohammed; Shiwen, Xu; Farooqui, Noreen; Ramesh, Bala; Welch, Hazel; Savage, Felicity J; Ogunbiyi, Olagunju; Abraham, David J; Loizidou, Marilena

    2013-08-01

    Endothelin 1 (ET-1) is overexpressed in cancer, contributing to disease progression. We previously showed that ET-1 stimulated proliferative, migratory, and contractile tumorigenic effects via the ET(A) receptor. Here, for the first time, we evaluate zibotentan, a specific ET(A) receptor antagonist, in the setting of colorectal cancer, in cellular models. Pharmacologic characteristics were further determined in patient tissues. Colorectal cancer lines (n = 4) and fibroblast strains (n = 6), isolated from uninvolved areas of colorectal cancer specimens, were exposed to ET-1 and/or ET(A)/(B) receptor antagonists. Proliferation (methylene blue), migration (scratch wounds), and contraction (gel lattices) were assessed. Receptor distribution and binding characteristics (K(d), B(max)) were determined using autoradiography on tissue sections and homogenates and cytospun cells, supported by immunohistochemistry. Proliferation was inhibited by ET(A) (zibotentan > BQ123; P < 0.05), migration by ET(B) > ET(A), and contraction by combined ET(A) and ET(B) antagonism. Intense ET-1 stromal binding correlated with fibroblasts and endothelial cells. Colorectal cancer lines and fibroblasts revealed high density and affinity ET-1 binding (B(max) = 2.435 fmol/1 × 10(6) cells, K(d) = 367.7 pmol/L; B(max) = 3.03 fmol/1 × 10(6) cells, K(d) = 213.6 pmol/L). In cancer tissues, ET(A) receptor antagonists (zibotentan; BQ123) reduced ET-1 binding more effectively (IC(50): 0.1-10 μmol/L) than ET(B) receptor antagonist BQ788 (∼IC(50), 1 mmol/L). ET-1 stimulated cancer-contributory processes. Its localization to tumor stroma, with greatest binding/affinity to fibroblasts, implicates these cells in tumor progression. ET(A) receptor upregulation in cancer tissues and its role in tumorigenic processes show the receptor's importance in therapeutic targeting. Zibotentan, the most specific ET(A) receptor antagonist available, showed the greatest inhibition of ET-1 binding. With its known safety profile, we provide evidence for zibotentan's potential role as adjuvant therapy in colorectal cancer. PMID:23723122

  5. Preclinical models of pancreatic ductal adenocarcinoma.

    PubMed

    Hwang, Chang-Il; Boj, Sylvia F; Clevers, Hans; Tuveson, David A

    2016-01-01

    Pancreatic ductal adenocarcinoma (PDA) is one of the most difficult human malignancies to treat. The 5-year survival rate of PDA patients is 7% and PDA is predicted to become the second leading cancer-related cause of death in the USA. Despite intensive efforts, the translation of findings in preclinical studies has been ineffective, due partially to the lack of preclinical models that faithfully recapitulate features of human PDA. Here, we review current preclinical models for human PDA (eg human PDA cell lines, cell line-based xenografts and patient-derived tumour xenografts). In addition, we discuss potential applications of the recently developed pancreatic ductal organoids, three-dimensional culture systems and organoid-based xenografts as new preclinical models for PDA. Copyright 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:26419819

  6. Sources of variation in the design of preclinical studies assessing the effects of amphetamine-type stimulants in pregnancy and lactation.

    PubMed

    McDonnell-Dowling, Kate; Kelly, John P

    2015-02-15

    The prevalence of drug use during pregnancy has increased in recent years and the amount of drug-exposed babies has therefore increased. In order to assess the risk associated with this there has been an increase in the amount of preclinical studies investigating the effects of prenatal and postnatal drug exposure on the offspring. There are many challenges associated with investigating the developmental and behavioural effects of drugs of abuse in animal models and ensuring that such models are appropriate and clinically relevant. The purpose of this review is to illustrate the variation in the design of preclinical studies investigating the effects of the amphetamine-type stimulants taken during pregnancy and/or lactation in animal models. Methamphetamine, methylendioxymethamphetamine and amphetamine were included in this review. The protocols used for exploring the effects of these drugs when taking during pregnancy and/or lactation were investigated and summarised into maternal experimental variables and offspring experimental variables. Maternal experimental variables include animals used, mating procedures and drug treatment and offspring experimental variables include litter standardisation, cross fostering, weaning and behaviours and parameters assessed. The findings in this paper suggest that there is a large diversity and little consistency among these studies and so the interpretation of these results may not be as clinically relevant as previously thought. For this reason, the importance of steering the preclinical studies in a direction that is most clinically relevant will be an important future recommendation. This will also allow us to be more confident in the results obtained and confident that the human situation is being replicated as closely as possible. PMID:25449844

  7. Discovery of 5-aryl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones as positive allosteric modulators of metabotropic glutamate subtype-2 (mGlu2) receptors with efficacy in a preclinical model of psychosis.

    PubMed

    Layton, Mark E; Reif, Alexander J; Hartingh, Timothy J; Rodzinak, Kevin; Dudkin, Vadim; Wang, Cheng; Arrington, Ken; Kelly, Michael J; Garbaccio, Robert M; O'Brien, Julie A; Magliaro, Brian C; Uslaner, Jason M; Huszar, Sarah L; Fillgrove, Kerry L; Tang, Cuyue; Kuo, Yuhsin; Jacobson, Marlene A

    2016-02-15

    Optimization of a benzimidazolone template for potency and physical properties revealed 5-aryl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones as a key template on which to develop a new series of mGlu2 positive allosteric modulators (PAMs). Systematic investigation of aryl-SAR led to the identification of compound 27 as a potent and highly selective mGlu2 PAM with sufficient pharmacokinetics to advance to preclinical models of psychosis. Gratifyingly, compound 27 showed full efficacy in the PCP- and MK-801-induced hyperlocomotion assay in rats at CSF concentrations consistent with mGlu2 PAM potency. PMID:26810316

  8. A preclinical evaluation of an autologous living hyaline-like cartilaginous graft for articular cartilage repair: a pilot study

    PubMed Central

    Peck, Yvonne; He, Pengfei; Chilla, Geetha Soujanya V. N.; Poh, Chueh Loo; Wang, Dong-An

    2015-01-01

    In this pilot study, an autologous synthetic scaffold-free construct with hyaline quality, termed living hyaline cartilaginous graft (LhCG), was applied for treating cartilage lesions. Implantation of autologous LhCG was done at load-bearing regions of the knees in skeletally mature mini-pigs for 6 months. Over the course of this study, significant radiographical improvement in LhCG treated sites was observed via magnetic resonance imaging. Furthermore, macroscopic repair was effected by LhCG at endpoint. Microscopic inspection revealed that LhCG engraftment restored cartilage thickness, promoted integration with surrounding native cartilage, produced abundant cartilage-specific matrix molecules, and re-established an intact superficial tangential zone. Importantly, the repair efficacy of LhCG was quantitatively shown to be comparable to native, unaffected cartilage in terms of biochemical composition and biomechanical properties. There were no complications related to the donor site of cartilage biopsy. Collectively, these results imply that LhCG engraftment may be a viable approach for articular cartilage repair. PMID:26549401

  9. Performance characterization of a new CZT-based preclinical SPECT system: a comparative study of different collimators

    NASA Astrophysics Data System (ADS)

    Yu, A. R.; Park, S.-J.; Choi, Y. Y.; Kim, K. M.; Kim, H.-J.

    2015-09-01

    Triumph X-SPECT is a newly released CZT-based preclinical small-animal SPECT system with interchangeable collimators. The purpose of this work was to evaluate and systematically compare the imaging performances of three different collimators in the CZT-based preclinical small-animal system: a single-pinhole collimator (SPH), a multi-pinhole collimator (MPH) and a parallel-hole collimator. We measured the spatial resolutions and sensitivities of the three collimators with 99mTc sources, considering three distinct energy window widths (5, 10, and 20%), and used the NEMA NU4-2008 Image Quality phantom to test the imaging performance of the three collimators in terms of uniformity and spill-over ratio (SOR) for each energy window. With a 10% energy window width at a radius of rotation (ROR) of 30 mm, the system resolution of the SPH, MPH and parallel-hole collimators was 0.715, 0.855 and 3.270 mm FWHM, respectively. For the same energy window, the sensitivity of the system with SPH, MPH and parallel-hole collimators was 32.860, 152.514 and 49.205 counts/sec/MBq at a 100 mm source-to-detector distance and 6.790, 33.376 and 49.038 counts/sec/MBq at a 130 mm source-to-detector distance, respectively. The image noise and SORair for the three collimators were 20.137, 12.278 and 11.232 (%STDunif) and 0.106, 0.140 and 0.161, respectively. Overall, the results show that the SPH had better spatial resolution than the other collimators. The MPH had the highest sensitivity at 100 mm source-to-collimator distance, and the parallel-hole collimator had the highest sensitivity at 130 mm-source-to-detector distance. Therefore, the proper collimator for Triumph X-SPECT system must be determined by the task. These results provide valuable reference data and insight into the imaging performance of various collimators in CZT-based preclinical small-animal SPECT.

  10. Does interprofessional simulation increase self-efficacy: a comparative study

    PubMed Central

    Watters, Colm; Reedy, Gabriel; Ross, Alastair; Morgan, Nicola J; Handslip, Rhodri; Jaye, Peter

    2015-01-01

    Objectives In this work, we have compared uniprofessional and interprofessional versions of a simulation education intervention, in an attempt to understand more about whether it improves trainees’ self-efficacy. Background Interprofessionalism has been climbing the healthcare agenda for over 50 years. Simulation education attempts to create an environment for healthcare professionals to learn, without potential safety risks for patients. Integrating simulation and interprofessional education can provide benefits to individual learners. Setting The intervention took place in a high-fidelity simulation facility located on the campus of a large urban hospital. The centre provides educational activities for an Academic Health Sciences Centre. Approximately 2500 staff are trained at the centre each year. Participants One hundred and fifteen nurses and midwives along with 156 doctors, all within the early years of their postgraduate experience participated. All were included on the basis of their ongoing postgraduate education. Methods Each course was a one-day simulation course incorporating five clinical and one communication scenarios. After each a facilitated debriefing took place. A mixed methods approach utilised precourse and postcourse questionnaires measuring self-efficacy in managing emergency situations, communication, teamwork and leadership. Results Thematic analysis of qualitative data showed improvements in communication/teamwork and leadership, for doctors and nurses undergoing simulation training. These findings were confirmed by statistical analysis showing that confidence ratings improved in nurses and doctors overall (p<0.001). Improved outcomes from baseline were observed for interprofessional versus uniprofessional trained nurses (n=115; p<0.001). Postcourse ratings for doctors showed that interprofessional training was significantly associated with better final outcomes for a communication/teamwork dimension (n=156; p<0.05). Conclusions This study provides evidence that simulation training enhances participants’ self-efficacy in clinical situations. It also leads to increases in their perceived abilities relating to communication/teamwork and leadership/management of clinical scenarios. Interprofessional training showed increased positive effects on self-efficacy for nurses and doctors. PMID:25586366

  11. Genetic strategies to study TDP-43 in rodents and to develop preclinical therapeutics for amyotrophic lateral sclerosis.

    PubMed

    Wang, David B; Gitcho, Michael A; Kraemer, Brian C; Klein, Ronald L

    2011-10-01

    The neuropathological hallmark of the majority of amyotrophic lateral sclerosis (ALS) and a class of frontotemporal lobar degeneration is ubiquitinated cytoplasmic aggregates composed of transactive response DNA binding protein 43 kDa (TDP-43). Genetic manipulation of TDP-43 in animal models has been used to study the protein's role in pathogenesis. Transgenic rodents for TDP-43 have recapitulated key aspects of ALS such as paralysis, loss of spinal motor neurons and muscle atrophy. Viral vectors are an alternate approach to express pathological proteins in animals. Use of the recombinant adeno-associated virus vector serotype 9 has permitted widespread transgene expression throughout the central nervous system after intravenous administration. Expressing TDP-43 in rats with this method produced a phenotype that was consistent with and similar to TDP-43 transgenic lines. Increased levels of TDP-43 in the nucleus are toxic to neurons and sufficient to produce ALS-like symptoms. Animal models based on TDP-43 will address the relationships between TDP-43 expression levels, pathology, neuronal loss, muscle atrophy, motor function and causative mechanisms of disease. New targets that modify TDP-43 function, or targets from previous ALS models and other models of spinal cord diseases, could be tested for efficacy in the recent rodent models of ALS based on TDP-43. The vector approach could be an important therapeutic channel because the entire spinal cord can be affected from a one-time peripheral administration. PMID:21777407

  12. Genetic strategies to study TDP-43 in rodents and to develop preclinical therapeutics for amyotrophic lateral sclerosis

    PubMed Central

    Wang, David B.; Gitcho, Michael A.; Kraemer, Brian C.; Klein, Ronald L.

    2011-01-01

    The neuropathological hallmark of the majority of amyotrophic lateral sclerosis (ALS) and a class of frontotemporal lobar degeneration is ubiquitinated cytoplasmic aggregates composed of transactive response DNA binding protein 43 kDa (TDP-43). Genetic manipulation of TDP-43 in animal models has been used to study the protein's role in pathogenesis. Transgenic rodents for TDP-43 have recapitulated key aspects of ALS such as paralysis, loss of spinal motor neurons and muscle atrophy. Viral vectors are an alternate approach to express pathological proteins in animals. Use of the recombinant adeno-associated virus vector serotype 9 has permitted widespread transgene expression throughout the central nervous system after intravenous administration. Expressing TDP-43 in rats with this method produced a phenotype that was consistent with and similar to TDP-43 transgenic lines. Increased levels of TDP-43 in the nucleus are toxic to neurons and sufficient to produce ALS-like symptoms. Animal models based on TDP-43 will address the relationships between TDP-43 expression levels, pathology, neuronal loss, muscle atrophy, motor function and causative mechanisms of disease. New targets that modify TDP-43 function, or targets from previous ALS models and other models of spinal cord diseases, could be tested for efficacy in the recent rodent models of ALS based on TDP-43. The vector approach could be an important therapeutic channel because the entire spinal cord can be affected from a one-time peripheral administration. PMID:21777407

  13. Pharmacotherapy of cocaine abuse: preclinical development.

    PubMed

    Witkin, J M

    1994-01-01

    Preclinical models of behavioral and toxic effects of cocaine are reviewed and their potential for predicting compounds with efficacy and safety in the medical management of cocaine abuse and toxicity is assessed. Many of the existing models appear to be good predictors of the effects of compounds against specific behavioral or toxicological actions of cocaine. However, the utility of the models for prediction of the efficacy of new therapeutic entities must await clinical validation as no accepted or standard pharmacotherapy currently exists. Preclinical data generated by these models with drugs currently under clinical investigation for cocaine abuse treatment as well as with other compounds are reviewed. These compounds include buprenorphine, bromocriptine, desmethylimipramine, carbamazepine, dopaminergic agonists, antagonists and partial agonists, dopamine reuptake inhibitors, sigma ligands, serotonin antagonists, and excitatory amino acid antagonists. Preclinical information on several drug classes appears sufficiently promising to warrant further evaluation. These include dopamine agonists and partial agonists, D1 receptor antagonists, selective sigma ligands, and modulators of the N-methyl-D-aspartate subtype glutamate receptor. PMID:8170620

  14. Premarket Safety and Efficacy Studies for ADHD Medications in Children

    PubMed Central

    Bourgeois, Florence T.; Kim, Jeong Min; Mandl, Kenneth D.

    2014-01-01

    Background Attention-deficit hyperactivity disorder (ADHD) is a chronic condition and pharmacotherapy is the mainstay of treatment, with a variety of ADHD medications available to patients. However, it is unclear to what extent the long-term safety and efficacy of ADHD drugs have been evaluated prior to their market authorization. We aimed to quantify the number of participants studied and their length of exposure in ADHD drug trials prior to marketing. Methods We identified all ADHD medications approved by the Food and Drug Administration (FDA) and extracted data on clinical trials performed by the sponsor and used by the FDA to evaluate the drug’s clinical efficacy and safety. For each ADHD medication, we measured the total number of participants studied and the length of participant exposure and identified any FDA requests for post-marketing trials. Results A total of 32 clinical trials were conducted for the approval of 20 ADHD drugs. The median number of participants studied per drug was 75 (IQR 0, 419). Eleven drugs (55%) were approved after <100 participants were studied and 14 (70%) after <300 participants. The median trial length prior to approval was 4 weeks (IQR 2, 9), with 5 (38%) drugs approved after participants were studied <4 weeks and 10 (77%) after <6 months. Six drugs were approved with requests for specific additional post-marketing trials, of which 2 were performed. Conclusions Clinical trials conducted for the approval of many ADHD drugs have not been designed to assess rare adverse events or long-term safety and efficacy. While post-marketing studies can fill in some of the gaps, better assurance is needed that the proper trials are conducted either before or after a new medication is approved. PMID:25007171

  15. Towards developing standard operating procedures for pre-clinical testing in the mdx mouse model of Duchenne muscular dystrophy

    PubMed Central

    Grounds, Miranda D.; Radley, Hannah G.; Lynch, Gordon S.; Nagaraju, Kanneboyina; De Luca, Annamaria

    2008-01-01

    This review discusses various issues to consider when developing standard operating procedures for pre-clinical studies in the mdx mouse model of Duchenne muscular dystrophy (DMD). The review describes and evaluates a wide range of techniques used to measure parameters of muscle pathology in mdx mice and identifies some basic techniques that might comprise standardised approaches for evaluation. While the central aim is to provide a basis for the development of standardised procedures to evaluate efficacy of a drug or a therapeutic strategy, a further aim is to gain insight into pathophysiological mechanisms in order to identify other therapeutic targets. The desired outcome is to enable easier and more rigorous comparison of pre-clinical data from different laboratories around the world, in order to accelerate identification of the best pre-clinical therapies in the mdx mouse that will fast-track translation into effective clinical treatments for DMD. PMID:18499465

  16. Treatment of cognitive dysfunction in major depressive disorder--a review of the preclinical evidence for efficacy of selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors and the multimodal-acting antidepressant vortioxetine.

    PubMed

    Pehrson, Alan L; Leiser, Steven C; Gulinello, Maria; Dale, Elena; Li, Yan; Waller, Jessica A; Sanchez, Connie

    2015-04-15

    Although major depressive disorder is primarily considered a mood disorder, depressed patients commonly present with clinically significant cognitive dysfunction that may add to their functional disability. This review paper summarizes the available preclinical data on the effects of antidepressants, including monoamine reuptake inhibitors and the multimodal antidepressant vortioxetine, in behavioral tests of cognition such as cognitive flexibility, attention, and memory, or in potentially cognition-relevant mechanistic assays such as electroencephalography, in vivo microdialysis, in vivo or in vitro electrophysiology, and molecular assays related to neurogenesis or synaptic sprouting. The available data are discussed in context with clinically relevant doses and their relationship to target occupancy levels, in order to evaluate the translational relevance of preclinical doses used during testing. We conclude that there is preclinical evidence suggesting that traditional treatment with monoamine reuptake inhibitors can induce improved cognitive function, for example in cognitive flexibility and memory, and that the multimodal-acting antidepressant vortioxetine may have some advantages by comparison to these treatments. However, the translational value of the reviewed preclinical data can be questioned at times, due to the use of doses outside the therapeutically-relevant range, the lack of data on target engagement or exposure, the tendency to investigate acute rather than long term antidepressant administration, and the trend towards using normal rodents rather than models with translational relevance for depression. Finally, several suggestions are made for advancing this field, including expanded use of target occupancy assessments in preclinical and clinical experiments, and the use of translationally valuable techniques such as electroencephalography. PMID:25107284

  17. ISO 12189 standard for the preclinical evaluation of posterior spinal stabilization devices - II: A parametric comparative study.

    PubMed

    La Barbera, Luigi; Costa, Francesco; Villa, Tomaso

    2016-02-01

    The International Standardization Organization (ISO) 12189 standard was recently introduced to preclinically evaluate and compare the mechanical properties of posterior stabilization devices. This scenario presents some new significant steps ahead over the vertebrectomy model recommended by American Society for Testing and Materials (ASTM) F1717 standard: the modular anterior support allows for describing a closer scenario to the effective clinical use as well as to test very flexible and dynamic posterior stabilization devices. Despite these significant advantages, ISO 12189 received little attention in the literature. Anatomical parameters depending on the spinal level were compared to the published data or original measurements on biplanar stereoradiography on 13 patients. Other mechanical variables, describing the test set-up design, were considered and all parameters were investigated using a numerical parametric finite element model. Stress values were calculated by also considering their worst-case combination. The standard set-up represents quite well the anatomy of an instrumented average thoracolumbar segment. The parametric comparative analysis demonstrates a significant (even beyond +350%) maximum increase in the stress on the device, compared to the standard currently in use. The anterior support stiffness plays the most detrimental effect (maximum stress increases up to 396%). The initial precompression step has an important role in determining the final stress values achieved at peak load (up to +76%). Moreover, when combining these two contributions, an even higher stress increase may be achieved (up to 473%). Despite the other anatomical parameters playing a secondary role, their worst-case combination demonstrates that a device could potentially undergo higher stresses than those reached according to standard suggestions (maximum increase of 22.4% at L1). Any user/designer should be aware of these effects when using ISO 12189 standard for the preclinical evaluation of posterior spinal stabilization devices. PMID:26673809

  18. Late, never or non-existent: the inaccessibility of preclinical evidence for new drugs

    PubMed Central

    Federico, C A; Carlisle, B; Kimmelman, J; Fergusson, D A

    2014-01-01

    Background and Purpose Animal studies establish much of the evidence used to support clinical development of new drugs. Recent studies suggest that many preclinical investigations are withheld from publication, leading to exaggerated estimates of clinical utility. We sought to estimate the volume and properties of all published animal efficacy studies for a cohort of novel drugs. Experimental Approach We searched biomedical databases to identify 47 novel drugs whose first trials were reported between 2000 and 2003, inclusive. Next, we searched for all published animal studies testing the same drug, regardless of publication date. We then extracted items from titles and abstracts of eligible studies. Key Results We identified 2462 efficacy studies, representing an average of 52 studies per drug. No published efficacy studies were available for three drugs in our sample. The volume of efficacy studies was related to how far the drug had progressed in clinical development (Spearman's correlation coefficient = 0.66, P < 0.0001). Most (87%) accessible animal efficacy studies were reported after publication of the first trial, and for 17% of the drugs in our sample, no efficacy studies were published before the first trial report. Disease indications used in trials often did not match those modelled in efficacy studies; for 35% of indications tested in trials, we were unable to identify any published efficacy studies in models of the same indication. Conclusions and Implications The volume of published efficacy studies is large, although numerous gaps reflect non-publication, publication delay or non-performance of efficacy studies supporting trials. PMID:24825131

  19. Repositioning Antitubercular 6-Nitro-2,3-dihydroimidazo[2,1-b][1,3]oxazoles for Neglected Tropical Diseases: Structure-Activity Studies on a Preclinical Candidate for Visceral Leishmaniasis.

    PubMed

    Thompson, Andrew M; O'Connor, Patrick D; Blaser, Adrian; Yardley, Vanessa; Maes, Louis; Gupta, Suman; Launay, Delphine; Martin, Denis; Franzblau, Scott G; Wan, Baojie; Wang, Yuehong; Ma, Zhenkun; Denny, William A

    2016-03-24

    6-Nitro-2,3-dihydroimidazo[2,1-b][1,3]oxazole derivatives were initially studied for tuberculosis within a backup program for the clinical trial agent pretomanid (PA-824). Phenotypic screening of representative examples against kinetoplastid diseases unexpectedly led to the identification of DNDI-VL-2098 as a potential first-in-class drug candidate for visceral leishmaniasis (VL). Additional work was then conducted to delineate its essential structural features, aiming to improve solubility and safety without compromising activity against VL. While the 4-nitroimidazole portion was specifically required, several modifications to the aryloxy side chain were well-tolerated e.g., exchange of the linking oxygen for nitrogen (or piperazine), biaryl extension, and replacement of phenyl rings by pyridine. Several less lipophilic analogues displayed improved aqueous solubility, particularly at low pH, although stability toward liver microsomes was highly variable. Upon evaluation in a mouse model of acute Leishmania donovani infection, one phenylpyridine derivative (37) stood out, providing efficacy surpassing that of the original preclinical lead. PMID:26901446

  20. Essentials for starting a pediatric clinical study (4): Clinical pediatric safety planning based on preclinical toxicity studies and pediatric pharmacovigilance guidance.

    PubMed

    Sheth, Neha

    2009-01-01

    Juvenile toxicology studies in animals provide useful information to guide monitoring of potential adverse effects in children especially on growth and development. In order to continue to gain knowledge and build upon these preclinical studies, recent experience has suggested that additional approaches for monitoring of safety concerns in the pediatric population may be required. Recently, pediatric guidance has become available from the health authorities which provide pharmacovigilance concepts as they specifically relate to drugs being developed for pediatric indications. Clinical trials are typically not robust enough to detect rare or delayed safety effects as the pediatric trials are relatively short-term. Furthermore, such long term or rare effects may not be detected via standard voluntary postmarketing surveillance. Safety monitoring of children with Juvenile Inflammatory Arthritis (JIA) taking nonsteroid anti-inflammatory drug (NSAID)s will be used as an example to describe a post-marketing risk management and pharmacovigilance program that serves to better evaluate safety data from various sources. The intent of this program is to identify adverse events (AE), including events with longer latency, which may be associated with NSAID use in a pediatric population. In this presentation, the 4 major components of the program are to be addressed. Such a program may serve as a model to proactively generate and monitor safety data in order to identify AEs that may be associated with new therapeutics for a pediatric population. PMID:19571487

  1. Adjuvant bisphosphonate treatment for breast cancer: Where are we heading and can the pre-clinical literature help us get there?

    PubMed Central

    Russell, Kent; Clemons, Mark; Costa, Luis; Addison, Christina L.

    2012-01-01

    Bisphosphonates have demonstrated anti-tumour activity in preclinical studies of bone metastatic disease, thus it was natural to transition these agents into the adjuvant cancer therapy setting. Surprisingly, the results of adjuvant breast cancer trials have shown either modest to no benefit or even harm. We sought to explore whether the preclinical results supporting bisphosphonate use provided clues to help explain the current clinical data. Interestingly, the majority of preclinical data suggested that bisphosphonate treatment was more efficacious when administered after the establishment of osseous metastases. This is similar to the findings of one clinical study whereby patients with biopsy evidence of osseous micrometastases derive greater survival benefit from bisphosphonate treatment. Another clinical study found bisphosphonates were associated with increased incidence of visceral metastases, similar to what has been previously published in preclinical models using preventative dosing strategies. While the current clinical data suggest bisphosphonates may be more efficacious in post-menopausal or oestrogen depleted patients, or those with hormone receptor positive tumours, to date no appropriately designed preclinical studies have evaluated these effects. Furthermore, putative mechanisms that regulate response to bisphosphonates in other tumour types remain to be evaluated in breast cancer. Despite the initial optimism regarding adjuvant bisphosphonate therapy, the conflicting clinical results from large trials suggest that we should return to the bench to further investigate factors that may influence response to bisphosphonate treatment or identify appropriate characteristics that would indicate the sub-groups of patients most likely to benefit from bisphosphonate treatment.

  2. Human B-cell cancer cell lines as a preclinical model for studies of drug effect in diffuse large B-cell lymphoma and multiple myeloma.

    PubMed

    Laursen, Maria Bach; Falgreen, Steffen; Bdker, Julie Stve; Schmitz, Alexander; Kjeldsen, Malene Krag; Srensen, Suzette; Madsen, Jakob; El-Galaly, Tarec Christoffer; Bgsted, Martin; Dybkr, Karen; Johnsen, Hans Erik

    2014-11-01

    Drug resistance in cancer refers to recurrent or primary refractory disease following drug therapy. At the cellular level, it is a consequence of molecular functions that ultimately enable the cell to resist cell death-one of the classical hallmarks of cancer. Thus, drug resistance is a fundamental aspect of the cancer cell phenotype, in parallel with sustained proliferation, immortality, angiogenesis, invasion, and metastasis. Here we present a preclinical model of human B-cell cancer cell lines used to identify genes involved in specific drug resistance. This process includes a standardized technical setup for specific drug screening, analysis of global gene expression, and the statistical considerations required to develop resistance gene signatures. The state of the art is illustrated by the first-step classical drug screen (including the CD20 antibody rituximab, the DNA intercalating topoisomerase II inhibitor doxorubicin, the mitotic inhibitor vincristine, and the alkylating agents cyclophosphamide and melphalan) along with the generation of gene lists predicting the chemotherapeutic outcome as validated retrospectively in clinical trial datasets. This B-cell lineage-specific preclinical model will allow us to initiate a range of laboratory studies, with focus on specific gene functions involved in molecular resistance mechanisms. PMID:25072621

  3. A meta-analysis of threats to valid clinical inference in preclinical research of sunitinib.

    PubMed

    Henderson, Valerie C; Demko, Nadine; Hakala, Amanda; MacKinnon, Nathalie; Federico, Carole A; Fergusson, Dean; Kimmelman, Jonathan

    2015-01-01

    Poor study methodology leads to biased measurement of treatment effects in preclinical research. We used available sunitinib preclinical studies to evaluate relationships between study design and experimental tumor volume effect sizes. We identified published animal efficacy experiments where sunitinib monotherapy was tested for effects on tumor volume. Effect sizes were extracted alongside experimental design elements addressing threats to valid clinical inference. Reported use of practices to address internal validity threats was limited, with no experiments using blinded outcome assessment. Most malignancies were tested in one model only, raising concerns about external validity. We calculate a 45% overestimate of effect size across all malignancies due to potential publication bias. Pooled effect sizes for specific malignancies did not show apparent relationships with effect sizes in clinical trials, and we were unable to detect dose-response relationships. Design and reporting standards represent an opportunity for improving clinical inference. PMID:26460544

  4. Anti-Plaque Efficacy of Herbal and 0.2% Chlorhexidine Gluconate Mouthwash: A Comparative Study

    PubMed Central

    Prasad, K A Ravi Varma; John, Sajil; Deepika, V; Dwijendra, K S; Reddy, Babu Ram; Chincholi, Siddharth

    2015-01-01

    Background: Mouthwashes are an adjunct to, not a substitute for, regular brushing and flossing. Chlorohexidine is cationic bis-biguanide broad spectrum antiseptic with both anti-plaque and antibacterial properties. It has side-effects like brownish discoloration of teeth and dorsum of the tongue, taste perturbation, oral mucosal ulceration, etc. To compare the antiplaque efficacy of herbal and chlorohexidine gluconate mouthwash. Materials and Methods: A double-blinded parallel, randomized controlled clinical trial was conducted in the Department of Periodontics, MNR Dental College. Totally 100 preclinical dental students were randomized into three groups (0.2% chlorohexidine, Saline and herbal mouthwash). All the groups were made to refrain from their regular mechanical oral hygiene measures and were asked to rinse with given respective mouthwashes for 4 days. The gingival and plaque scores are evaluated on 1st day, and 5th day, and differences were compared statistically. Results: There was no significant difference in the gingival index (GI) and plaque index (PI) scores of the pre-rinsing scores of three groups and mean age of subjects in the three age groups, suggesting selected population for the three groups was homogenous. Mean GI and PI scores at the post rinsing stage were least for the Group A, followed by B and C. The difference of post rinsing PI and GI scores between Group A and Group B were statistically non-significant, which means anti-gingivitis and plaque inhibiting properties are similar for both. Conclusion: Within the limitations of this study chlorhexidine gluconate and herbal mouthwash (Hiora) showed similar anti plaque activity with latter showing no side effects. PMID:26464549

  5. An Exploratory Study of Teacher Self-Efficacy Beliefs and Professional Learning Community

    ERIC Educational Resources Information Center

    Romeo, Susan M.

    2010-01-01

    The exploratory study sought to examine the relationships between teachers' self-efficacy beliefs and professional learning community. Specifically, this study presents a quantitative analysis of the relationship between teachers' perceptions of self-efficacy and PLC implementation. The Teachers' Sense of Efficacy Scale (TSES) (long form)

  6. Effect of Stem Cell Therapy on Bone Mineral Density: A Meta-Analysis of Preclinical Studies in Animal Models of Osteoporosis

    PubMed Central

    Li, Feng; Zhou, Changlin; Xu, Liang; Tao, Shuqing; Zhao, Jingyi; Gu, Qun

    2016-01-01

    Background Preclinical studies of the therapeutic role of stem cell based therapy in animal models of osteoporosis have largely yielded inconsistent results. We performed a meta-analysis to provide an overview of the currently available evidence. Methods Pubmed, Embase and Cochrane Library databases were systematically searched for relevant controlled studies. A random-effect model was used for pooled analysis of the effect of stem cell based therapy on bone mineral density (BMD). Stratified analyses were performed to explore the effect of study characteristics on the outcomes. Results Pooled results from 12 preclinical studies (110 animals in stem cell treatment groups, and 106 animals in control groups) indicated that stem cell based treatment was associated with significantly improved BMD (standardized mean difference [SMD] = 1.29, 95% Confidence Interval [CI]: 0.84–1.74, P < 0.001) with moderate heterogeneity (Cochrane’s Q test: P = 0.02, I2 = 45%) among the constituent studies. Implantation of bone marrow cells, bone marrow mesenchymal stem cells, adipose-derived stem cells, and human umbilical cord blood-derived CD34+ cells, were all associated with improved BMD as compared to that in the controls (P < 0.05 for all); the only exception being the use of embryonic stem cell transplantation (P > 0.05). Egger’s test detected potential publication bias (P = 0.055); however, ‘trim and fill’ analysis yielded similar results after statistically incorporating the hypothetical studies in the analysis (SMD = 1.24, 95% CI: 0.32–2.16, P < 0.001). Conclusions Stem cell transplantation may improve BMD in animal models of osteoporosis. Our meta-analysis indicates a potential therapeutic role of stem cell based therapy for osteoporosis, and serves to augment the rationale for clinical studies. PMID:26882451

  7. [Studies of biologic activation associated with molecular receptor increase and tumor response in ChL6/L6 protocol patients; Studies in phantoms; Quantitative SPECT; Preclinical studies; and Clinical studies]. DOE annual report, 1994--95

    SciTech Connect

    DeNardo, S.J.

    1995-12-31

    The authors describe results which have not yet been published from their associated studies listed in the title. For the first, they discuss Lym-1 single chain genetically engineered molecules, analysis of molecular genetic coded messages to enhance tumor response, and human dosimetry and therapeutic human use radiopharmaceuticals. Studies in phantoms includes a discussion of planar image quantitation, counts coincidence correction, organ studies, tumor studies, and {sup 90}Y quantitation with Bremsstrahlung imaging. The study on SPECT discusses attenuation correction and scatter correction. Preclinical studies investigated uptake of {sup 90}Y-BrE-3 in mice using autoradiography. Clinical studies discuss image quantitation verses counts from biopsy samples, S factors for radiation dose calculation, {sup 67}Cu imaging studies for lymphoma cancer, and {sup 111}In MoAb imaging studies for breast cancer to predict {sup 90}Y MoAb therapy.

  8. S 17092: a prolyl endopeptidase inhibitor as a potential therapeutic drug for memory impairment. Preclinical and clinical studies.

    PubMed

    Morain, Philippe; Lestage, Pierre; De Nanteuil, Guillaume; Jochemsen, Roeline; Robin, Jean-Loc; Guez, David; Boyer, Pierre-Alain

    2002-01-01

    Any treatment that could positively modulate central neuropeptides levels would provide a promising therapeutic approach to the treatment of cognitive deficits associated with aging and/or neurodegenerative diseases. Therefore, based on the activity in rodents, S 17092 (2S,3aS,7aS)-1][(R,R)-2-phenylcyclopropyl]carbonyl]-2-[(thiazolidin-3-yl)carbonyl]octahydro-1H-indole) has been selected as a potent inhibitor of cerebral prolyl-endopeptidase (PEP). By retarding the degradation of neuroactive peptides, S 17092 was successfully used in a variety of memory tasks. These tasks explored short-term, long-term, reference and working memory in aged mice, as well as in rodents and monkeys with chemically induced amnesia or spontaneous memory deficits. S 17092 has also been safely administered to humans, and showed a clear peripheral expression of its mechanism of action through its inhibitory effect upon PEP activity in plasma. S 17092 exhibited central effects, as evidenced by EEG recording in healthy volunteers, and could improve a delayed verbal memory task. Collectively, the preclinical and clinical effects of S 17092 have suggested a promising role for this compound as an agent for the treatment of cognitive disorders associated with cerebral aging. PMID:12070525

  9. Monitoring of anti-cancer treatment with 18F-FDG and 18F-FLT PET: a comprehensive review of pre-clinical studies

    PubMed Central

    Jensen, Mette Munk; Kjaer, Andreas

    2015-01-01

    Functional imaging of solid tumors with positron emission tomography (PET) imaging is an evolving field with continuous development of new PET tracers and discovery of new applications for already implemented PET tracers. During treatment of cancer patients, a general challenge is to measure treatment effect early in a treatment course and by that to stratify patients into responders and non-responders. With 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG) and 3’-deoxy-3’-[18F]fluorothymidine(18F-FLT) two of the cancer hallmarks, altered energy metabolism and increased cell proliferation, can be visualized and quantified non-invasively by PET. With 18F-FDG and 18F-FLT PET changes in energy metabolism and cell proliferation can thereby be determined after initiation of cancer treatment in both clinical and pre-clinical studies in order to predict, at an early time-point, treatment response. It is hypothesized that decreases in glycolysis and cell proliferation may occur in tumors that are sensitive to the applied cancer therapeutics and that tumors that are resistant to treatment will show unchanged glucose metabolism and cell proliferation. Whether 18F-FDG and/or 18F-FLT PET can be used for prediction of treatment response has been analyzed in many studies both following treatment with conventional chemotherapeutic agents but also following treatment with different targeted therapies, e.g. monoclonal antibodies and small molecules inhibitors. The results from these studies have been most variable; in some studies early changes in 18F-FDG and 18F-FLT uptake predicted later tumor regression whereas in other studies no change in tracer uptake was observed despite the treatment being effective. The present review gives an overview of pre-clinical studies that have used 18F-FDG and/or 18F-FLT PET for response monitoring of cancer therapeutics. PMID:26550536

  10. Preclinical Rheumatoid Arthritis (Autoantibodies): An Updated Review

    PubMed Central

    Deane, Kevin D.

    2014-01-01

    Multiple studies demonstrate that there is a period of development of rheumatoid arthritis (RA) during which there are elevations of disease-related biomarkers, including autoantibodies, in the absence of and prior to the development of RA; this period can be termed preclinical RA. These preclinical autoantibodies including rheumatoid factor and antibodies to citrullinated protein antigens, and more recent studies have also identified a wider variety of autoantibodies and a wide range of inflammatory biomarkers. These findings in conjunction with established and emerging data about genetic and environmental risk factors for RA support a model of disease development where certain factors lead to an initial triggering of RA-related autoimmunity that expands over time to the point where symptomatic arthritis classifiable as RA develops. Herein will be reviewed updates in the field, as well as a discussion of current limitations of our understanding of preclinical RA, and potential future directions for study. PMID:24643396

  11. The isolation, Characterization and Preclinical Studies of Metal Complex of Thespesia populnea for the Potential Peroxisome Proliferator-activated Receptors-γ Agonist Activity

    PubMed Central

    Phanse, Mohini Ashok; Patil, Manohar Janardhan; Abbulu, Konde

    2015-01-01

    Background: Diabetes mellitus is an international public health problem since ancient days. The condition is predominantly more severe in developing countries like India where, life is more sedentary due to the even changing lifestyles in this fast-paced global scenario. Thespesia populnea is widely used in the ayurvedic system of medicine for treatment of diabetes mellitus in India for years. The aim of this work is to explore the anti-diabetic activity of the isolated compound. Materials and Methods: The sesquiterpene isolated from hexane fraction of bark of T. populnea modified synthetically then identified by using analytical techniques such as electron paramagnetic resonance spectra for confirmation and the anti-diabetic activity was evaluated by anti-hyperglycemic, hypoglycemic potential. Result: In the present work, we have studied the anti-hyperglycemic and hypoglycemic activity of the vanadium complex in glucose loaded and normal animals were shown significantly decreased in plasma blood glucose level. The results derived from preclinical studies confirm the potential of new sesquiterpene. Conclusion: The findings could provide evidence regarding the anti-diabetic potential of T. populnea by lowering blood glucose level. SUMMARY Thespesia populnea is widely used in the ayurvedic system of medicine for treatment of diabetes in India. Present study aimed to explore the anti diabetic potential of isolated compound. Isolation of sesquiterpene from hexane fraction of bark of Thespesia populnea and modified synthetically then authenticated by using analytical techniques such as electron paramagnetic resonance spectra for confirmation. The modified complex was further assessed for its anti diabetic property in glucose loaded rats. Vanadium complex demonstrated significant reduction in plasma blood glucose level in glucose loaded animals. The results derived from preclinical studies confirm the potential of new sesquiterpene. The present findings conclude that anti diabetic potential of Thespesia populnea could be due to lowering blood glucose level by acting on PPAR-γ receptor. PMID:26929578

  12. HIV vaccine development: strategies for preclinical and clinical investigation.

    PubMed

    Shapiro, Stuart Z

    2013-11-01

    This article discusses HIV vaccine discovery and candidate vaccine testing in the context of current realities of funding and clinical trial practice. Lacking perfect animal models for testing candidate HIV vaccines, clinical investigators have proposed a strategy of iterative exploratory clinical trials in the model of cancer chemotherapy development. Problems with the appropriateness of this model to HIV vaccine development are discussed. Also, the future feasibility of this strategy in the context of increasing clinical trial costs and emerging new, efficacious prevention modalities is questioned. Strategies for making better use of animal models are presented as an alternative to iterative exploratory clinical efficacy testing. Some ways in which better data from preclinical studies can refine clinical product development are described. Finally, development of an HIV vaccine under the FDA's "Animal Rule" pathway to licensure when human efficacy studies are not feasible is discussed as a fall-back approach. Not making a preventive vaccine against HIV infection is simply not an option because eradication of AIDS will require a preventive vaccine. PMID:23379343

  13. A preclinical assay for chemosensitivity in multiple myeloma

    PubMed Central

    Khin, Zayar P.; Ribeiro, Maria L. C.; Jacobson, Timothy; Hazlehurst, Lori; Perez, Lia; Baz, Rachid; Shain, Kenneth; Silva, Ariosto S.

    2013-01-01

    Accurate preclinical predictions of the clinical efficacy of experimental cancer drugs are highly desired but often haphazard. Such predictions might be improved by incorporating elements of the tumor microenvironment in preclinical models by providing a more physiological setting. In generating improved xenograft models, it is generally accepted that the use of primary tumors from patients are preferable to clonal tumor cell lines. Here we describe an interdisciplinary platform to study drug response in multiple myeloma (MM), an incurable cancer of the bone marrow. This platform uses microfluidic technology to minimize the number of cells per experiment, while incorporating 3D extracellular matrix and mesenchymal cells derived from the tumor microenvironment. We used sequential imaging and a novel digital imaging analysis algorithm to quantify changes in cell viability. Computational models were used convert experimental data into dose-exposure-response "surfaces" which offered predictive utility. Using this platform, we predicted chemosensitivity to bortezomib and melphalan, two clinical MM treatments, in 3 MM cell lines and 7 patient-derived primary MM cell populations. We also demonstrated how this system could be used to investigate environment-mediated drug resistance and drug combinations that target it. This interdisciplinary preclinical assay is capable of generating quantitative data that can be used in computational models of clinical response, demonstrating its utility as a tool to contribute to personalized oncology. Major Findings By designing an experimental platform with the specific intent of generating experimental parameters for a computational clinical model of personalized therapy in multiple myeloma, while taking in consideration the limitations of working with patient primary cells, and the need to incorporate elements of the tumor microenvironment, we have generated patient-individualized estimations of initial response and time to relapse to chemotherapeutic agents. PMID:24310398

  14. Self Efficacy and Cultural Awareness: A Study of Returned Peace Corps Teachers.

    ERIC Educational Resources Information Center

    Cross, Mary Catherine

    This study investigated how returned Peace Corps teachers viewed the Peace Corps experience and its impact on their self-efficacy and cultural awareness. Participants were 154 returned Peace Corps teachers who completed a questionnaire that contained demographic questions, a self-efficacy scale, and a teacher-efficacy scale. A subset of 15

  15. Preservice Elementary Teachers' Perceived Efficacy in Teaching Environmental Education: A Preliminary Study.

    ERIC Educational Resources Information Center

    Sia, Archibald P.

    This study was designed to develop an instrument that would measure preservice teachers' belief efficacy in teaching environmental education (EE). This belief efficacy includes a person's perception of ability to perform the behavior (self-efficacy) and a person's expectation that a specific behavior will result in desirable outcomes (outcome

  16. Teacher Self-Efficacy and Teacher Burnout: A Study of Relations

    ERIC Educational Resources Information Center

    Skaalvik, Einar M.; Skaalvik, Sidsel

    2010-01-01

    The purpose of this study was partly to test the factor structure of a recently developed Norwegian scale for measuring teacher self-efficacy and partly to explore relations between teachers' perception of the school context, teacher self-efficacy, collective teacher efficacy, teacher burnout, teacher job satisfaction, and teachers' beliefs that

  17. Miniature Swine for Preclinical Modeling of Complexities of Human Disease for Translational Scientific Discovery and Accelerated Development of Therapies and Medical Devices.

    PubMed

    Schomberg, Dominic T; Tellez, Armando; Meudt, Jennifer J; Brady, Dane A; Dillon, Krista N; Arowolo, Folagbayi K; Wicks, Joan; Rousselle, Serge D; Shanmuganayagam, Dhanansayan

    2016-04-01

    Noncommunicable diseases, including cardiovascular disease, diabetes, chronic respiratory disease, and cancer, are the leading cause of death in the world. The cost, both monetary and time, of developing therapies to prevent, treat, or manage these diseases has become unsustainable. A contributing factor is inefficient and ineffective preclinical research, in which the animal models utilized do not replicate the complex physiology that influences disease. An ideal preclinical animal model is one that responds similarly to intrinsic and extrinsic influences, providing high translatability and concordance of preclinical findings to humans. The overwhelming genetic, anatomical, physiological, and pathophysiological similarities to humans make miniature swine an ideal model for preclinical studies of human disease. Additionally, recent development of precision gene-editing tools for creation of novel genetic swine models allows the modeling of highly complex pathophysiology and comorbidities. As such, the utilization of swine models in early research allows for the evaluation of novel drug and technology efficacy while encouraging redesign and refinement before committing to clinical testing. This review highlights the appropriateness of the miniature swine for modeling complex physiologic systems, presenting it as a highly translational preclinical platform to validate efficacy and safety of therapies and devices. PMID:26839324

  18. The role of metabotropic glutamate receptor 5 in the pathogenesis of mood disorders and addiction: combining preclinical evidence with human Positron Emission Tomography (PET) studies

    PubMed Central

    Terbeck, Sylvia; Akkus, Funda; Chesterman, Laurence P.; Hasler, Gregor

    2015-01-01

    In the present review, we deliver an overview of the involvement of metabotropic glutamate receptor 5 (mGluR5) activity and density in pathological anxiety, mood disorders and addiction. Specifically, we will describe mGluR5 studies in humans that employed Positron Emission Tomography (PET) and combined the findings with preclinical animal research. This combined view of different methodological approachesfrom basic neurobiological approaches to human studiesmight give a more comprehensive and clinically relevant view of mGluR5 function in mental health than the view on preclinical data alone. We will also review the current research data on mGluR5 along the Research Domain Criteria (RDoC). Firstly, we found evidence of abnormal glutamate activity related to the positive and negative valence systems, which would suggest that antagonistic mGluR5 intervention has prominent anti-addictive, anti-depressive and anxiolytic effects. Secondly, there is evidence that mGluR5 plays an important role in systems for social functioning and the response to social stress. Finally, mGluR5's important role in sleep homeostasis suggests that this glutamate receptor may play an important role in RDoC's arousal and modulatory systems domain. Glutamate was previously mostly investigated in non-human studies, however initial human clinical PET research now also supports the hypothesis that, by mediating brain excitability, neuroplasticity and social cognition, abnormal metabotropic glutamate activity might predispose individuals to a broad range of psychiatric problems. PMID:25852460

  19. Learning style preferences and academic success of preclinical allied health students.

    PubMed

    Good, Jonathan P; Ramos, Diane; D'Amore, Domenic C

    2013-01-01

    Student learning style modality preferences, in preclinical classes, were assessed using the visual-aural-read/write-kinesthetic (VARK) inventory. Preferences were assessed for 137 preclinical students, including those in nursing, physician's assistant, physical therapy, athletic training, and natural science programs using the online VARK inventory. All classes contained a majority of multimodal and a significantly high proportion of kinesthetic learners. No correlations were noted between modality preference strength and assessment performance in general biology classes; significant correlations were discovered for kinesthetic preference among the same cohort in subsequent human anatomy (negative correlation) and general physiology (positive correlation) classes. Assessment performance of nursing students in an anatomy and physiology class resulted in correlations with aural (negative correlation) and visual (positive correlation) preference strengths. Study findings are used to evaluate the efficacy of non-omnimodal delivery of content-focused science classes, before the students have developed the background knowledge or skills required to contextualize the learning. PMID:24326923

  20. Learning and confirming with preclinical studies: modeling and simulation in the discovery of GDC-0917, an inhibitor of apoptosis proteins antagonist.

    PubMed

    Wong, Harvey; Gould, Stephen E; Budha, Nageshwar; Darbonne, Walter C; Kadel, Edward E; La, Hank; Alicke, Bruno; Halladay, Jason S; Erickson, Rebecca; Portera, Chia; Tolcher, Anthony W; Infante, Jeffery R; Mamounas, Michael; Flygare, John A; Hop, Cornelis E C A; Fairbrother, Wayne J

    2013-12-01

    The application of modeling and simulation techniques is increasingly common in the preclinical stages of the drug development process. GDC-0917 [(S)-1-((S)-2-cyclohexyl-2-((S)-2-(methylamino)propanamido)acetyl)-N-(2-(oxazol-2-yl)-4-phenylthiazol-5-yl)pyrrolidine-2-carboxamide] is a potent second-generation antagonist of inhibitor of apoptosis (IAP) proteins that is being developed for the treatment of various cancers. GDC-0917 has low to moderate clearance in the mouse (12.0 ml/min/kg), rat (27.0 ml/min/kg), and dog (15.3 ml/min/kg), and high clearance in the monkey (67.6 ml/min/kg). Accordingly, oral bioavailability was lowest in monkeys compared with other species. Based on our experience with a prototype molecule with similar structure, in vitro-in vivo extrapolation was used to predict a moderate clearance (11.5 ml/min/kg) in humans. The predicted human volume of distribution was estimated using simple allometry at 6.69 l/kg. Translational pharmacokinetic-pharmacodynamic (PK-PD) analysis using results from MDA-MB-231-X1.1 breast cancer xenograft studies and predicted human pharmacokinetics suggests that ED50 and ED90 targets can be achieved in humans using acceptable doses (72 mg and 660 mg, respectively) and under an acceptable time frame. The relationship between GDC-0917 concentrations and pharmacodynamic response (cIAP1 degradation) was characterized using an in vitro peripheral blood mononuclear cell immunoassay. Simulations of human GDC-0917 plasma concentration-time profile and cIAP1 degradation at the 5-mg starting dose in the phase 1 clinical trial agreed well with observations. This work shows the importance of leveraging information from prototype molecules and illustrates how modeling and simulation can be used to add value to preclinical studies in the early stages of the drug development process. PMID:24041744

  1. Preclinical Pharmacology and Opioid Combinations

    PubMed Central

    Pasternak, Gavril W.

    2012-01-01

    Although effective alone, opioids are often used in combination with other drugs for relief of moderate to severe pain. Guidelines for acute perioperative pain recommend the use of multimodal therapy for pain management although combinations of opioids are not specifically recommended. Mu opioid drugs include morphine, heroin, fentanyl, methadone, and morphine 6?-glucuronide (M6G). Their mechanism of action is complex, resulting in subtle pharmacological differences among them and with unpredictable differences in their potency, effectiveness, and tolerability among patients. Highly selective mu opioids do not bind to a single receptor. Rather, they interact with a large number of mu receptor subtypes with different activation profiles for the various drugs. Thus, mu-receptor-based drugs are not all the same and it may be possible utilize these differences for enhanced pain control in a clinical setting. These differences among the drugs raise the question of whether combinations might result in better pain relief with fewer side effects. This concept already has been demonstrated between two mu opioids in preclinical studies and clinical trials other combinations are ongoing. This article reviews the current state of knowledge about mu opioid receptor pharmacology, summarizes preclinical evidence for synergy from opioid combinations, and highlights the complex nature of the mu opioid receptor pharmacology. PMID:22420604

  2. The Economics of Reproducibility in Preclinical Research.

    PubMed

    Freedman, Leonard P; Cockburn, Iain M; Simcoe, Timothy S

    2015-06-01

    Low reproducibility rates within life science research undermine cumulative knowledge production and contribute to both delays and costs of therapeutic drug development. An analysis of past studies indicates that the cumulative (total) prevalence of irreproducible preclinical research exceeds 50%, resulting in approximately US$28,000,000,000 (US$28B)/year spent on preclinical research that is not reproducible-in the United States alone. We outline a framework for solutions and a plan for long-term improvements in reproducibility rates that will help to accelerate the discovery of life-saving therapies and cures. PMID:26057340

  3. The Economics of Reproducibility in Preclinical Research

    PubMed Central

    Freedman, Leonard P.; Cockburn, Iain M.; Simcoe, Timothy S.

    2015-01-01

    Low reproducibility rates within life science research undermine cumulative knowledge production and contribute to both delays and costs of therapeutic drug development. An analysis of past studies indicates that the cumulative (total) prevalence of irreproducible preclinical research exceeds 50%, resulting in approximately US$28,000,000,000 (US$28B)/year spent on preclinical research that is not reproduciblein the United States alone. We outline a framework for solutions and a plan for long-term improvements in reproducibility rates that will help to accelerate the discovery of life-saving therapies and cures. PMID:26057340

  4. Comparative Effectiveness of 3-Dimensional vs 2-Dimensional and High-Definition vs Standard-Definition Neuroendoscopy: A Preclinical Randomized Crossover Study

    PubMed Central

    Hughes-Hallett, Archie; Cundy, Thomas P.; Di Marco, Aimee; Pratt, Philip; Nandi, Dipankar; Darzi, Ara; Yang, Guang-Zhong

    2013-01-01

    BACKGROUND: Although the potential benefits of 3-dimensional (3-D) vs 2-dimensional (2-D) and high-definition (HD) vs standard-definition (SD) endoscopic visualization have long been recognized in other surgical fields, such endoscopes are generally considered too large and bulky for use within the brain. The recent development of 3-D and HD neuroendoscopes may therefore herald improved depth perception, better appreciation of anatomic details, and improved overall surgical performance. OBJECTIVE: To compare simultaneously the effectiveness of 3-D vs 2-D and HD vs SD neuroendoscopy. METHODS: Ten novice neuroendoscopic surgeons were recruited from a university hospital. A preclinical randomized crossover study design was adopted to compare 3-D vs 2-D and HD vs SD neuroendoscopy. The primary outcomes were time to task completion and accuracy. The secondary outcomes were perceived task workload using the NASA (National Aeronautics and Space Administration) Task Load Index and subjective impressions of the endoscopes using a 5-point Likert scale. RESULTS: Time to task completion was significantly shorter when using the 3-D vs the 2-D neuroendoscopy (P = .001), and accuracy of probe placement was significantly greater when using the HD vs the SD neuroendoscopy (P = .009). We found that 3-D endoscopy significantly improved perceived depth perception (P < .001), HD endoscopy significantly improved perceived image quality (P < .001), and both improved participants’ overall impression (P < .001). CONCLUSION: Three-dimensional neuroendoscopy and HD neuroendoscopy have differing but complementary effects on surgical performance, suggesting that neither alone can completely compensate for the lack of the other. There is therefore strong preclinical evidence to justify 3-D HD neuroendoscopy. ABBREVIATIONS: HD, high definition SD, standard definition PMID:24220007

  5. Preclinical Operative Dentistry Courses in Northern Europe and Scandinavia.

    ERIC Educational Resources Information Center

    Wilson, N. H. F.; And Others

    1993-01-01

    This study compares teaching methods, time spent, and materials used in the existing preclinical teaching efforts of dental schools in 11 Northern European states (Belgium, Denmark, Eire, Finland, France, Germany, Netherlands, Norway, Sweden, Switzerland, and United Kingdom). Results reveal considerable variation in the teaching of preclinical

  6. Novel HDAC inhibitors exhibit pre-clinical efficacy in lymphoma models and point to the importance of CDKN1A expression levels in mediating their anti-tumor response.

    PubMed

    Mensah, Afua Adjeiwaa; Kwee, Ivo; Gaudio, Eugenio; Rinaldi, Andrea; Ponzoni, Maurilio; Cascione, Luciano; Fossati, Gianluca; Stathis, Anastasios; Zucca, Emanuele; Caprini, Gianluca; Bertoni, Francesco

    2015-03-10

    We investigated the pre-clinical activities of two novel histone deacetylase inhibitors (HDACi), ITF-A and ITF-B, in a large panel of pre-clinical lymphoma models. The two compounds showed a dose-dependent anti-proliferative activity in the majority of cell lines. Gene expression profiling (GEP) of diffuse large B-cell lymphoma (DLBCL) cells treated with the compounds showed a modulation of genes involved in chromatin structure, cell cycle progression, apoptosis, B-cell signaling, and genes encoding metallothioneins. Cell lines showed differences between the concentrations of ITF-A and ITF-B needed to cause anti-proliferative or cytotoxic activity, and cell cycle and apoptosis genes appeared implicated in determining the type of response. In particular, CDKN1A expression was higher in DLBCL cells that, to undergo apoptosis, required a much higher amount of drug than that necessary to induce only an anti-proliferative effect.In conclusion, the two novel HDACi ITF-A and ITF-B demonstrated anti-proliferative activity across different mature B-cell lymphoma cell lines. Basal CDKN1A levels appeared to be important in determining the gap between HDACi concentrations causing cell cycle arrest and those that lead to cell death. PMID:25671298

  7. Novel HDAC inhibitors exhibit pre-clinical efficacy in lymphoma models and point to the importance of CDKN1A expression levels in mediating their anti-tumor response

    PubMed Central

    Mensah, Afua Adjeiwaa; Kwee, Ivo; Gaudio, Eugenio; Rinaldi, Andrea; Ponzoni, Maurilio; Cascione, Luciano; Fossati, Gianluca; Stathis, Anastasios; Zucca, Emanuele; Caprini, Gianluca; Bertoni, Francesco

    2015-01-01

    We investigated the pre-clinical activities of two novel histone deacetylase inhibitors (HDACi), ITF-A and ITF-B, in a large panel of pre-clinical lymphoma models. The two compounds showed a dose-dependent anti-proliferative activity in the majority of cell lines. Gene expression profiling (GEP) of diffuse large B-cell lymphoma (DLBCL) cells treated with the compounds showed a modulation of genes involved in chromatin structure, cell cycle progression, apoptosis, B-cell signaling, and genes encoding metallothioneins. Cell lines showed differences between the concentrations of ITF-A and ITF-B needed to cause anti-proliferative or cytotoxic activity, and cell cycle and apoptosis genes appeared implicated in determining the type of response. In particular, CDKN1A expression was higher in DLBCL cells that, to undergo apoptosis, required a much higher amount of drug than that necessary to induce only an anti-proliferative effect. In conclusion, the two novel HDACi ITF-A and ITF-B demonstrated anti-proliferative activity across different mature B-cell lymphoma cell lines. Basal CDKN1A levels appeared to be important in determining the gap between HDACi concentrations causing cell cycle arrest and those that lead to cell death. PMID:25671298

  8. Evaluation of dendrimer safety and efficacy through cell line studies.

    PubMed

    Kesharwani, Prashant; Gajbhiye, Virendra; Tekade, Rakesh K; Jain, Narendra K

    2011-09-01

    Dendrimers, by virtue of their therapeutic value, have recently generated enormous interest among biomedical scientists. Advancement of dendrimeric nano-architecture with well defined size, shape and controlled exterior functionality embraces promise in biomedical and pharmaceutical applications such as drug delivery, solubilization, DNA transfection and diagnosis. Highly branched, monodisperse, stable molecular level and low polydispersity with micelle-like behavior possessing nano-scale container property distinguish these structures as inimitable and optimum carrier for those applications. Dendrimers has been evaluated for delivery of different types of bioactives inside the cells. Different types of techniques are being used for exploring dendrimer safety and efficacy via cell cytotoxicity assays, cell uptake studies by fluorescent microscopy, cell line studies, flow cytometry, gamma scintigraphy and confocal microscopy; are being used over a decade. Among these, cell line studies are widely used for ex vivo characterization of dendrimers and other nanocarriers. Cell lines are homogeneous population of cells, stable after mitosis, and have an unlimited capacity for division. This review focuses on the use of different cell line studies including anticancer drugs, anti-HIV drugs, anti-inflammatory drugs, anti-tubercular-drugs, photodynamic therapy, hormonal therapy employing dendritic nanocarrier. PMID:21443471

  9. Nebulized anticoagulants for acute lung injury - a systematic review of preclinical and clinical investigations

    PubMed Central

    2012-01-01

    Background Data from interventional trials of systemic anticoagulation for sepsis inconsistently suggest beneficial effects in case of acute lung injury (ALI). Severe systemic bleeding due to anticoagulation may have offset the possible positive effects. Nebulization of anticoagulants may allow for improved local biological availability and as such may improve efficacy in the lungs and lower the risk of systemic bleeding complications. Method We performed a systematic review of preclinical studies and clinical trials investigating the efficacy and safety of nebulized anticoagulants in the setting of lung injury in animals and ALI in humans. Results The efficacy of nebulized activated protein C, antithrombin, heparin and danaparoid has been tested in diverse animal models of direct (for example, pneumonia-, intra-pulmonary lipopolysaccharide (LPS)-, and smoke inhalation-induced lung injury) and indirect lung injury (for example, intravenous LPS- and trauma-induced lung injury). Nebulized anticoagulants were found to have the potential to attenuate pulmonary coagulopathy and frequently also inflammation. Notably, nebulized danaparoid and heparin but not activated protein C and antithrombin, were found to have an effect on systemic coagulation. Clinical trials of nebulized anticoagulants are very limited. Nebulized heparin was found to improve survival of patients with smoke inhalation-induced ALI. In a trial of critically ill patients who needed mechanical ventilation for longer than two days, nebulized heparin was associated with a higher number of ventilator-free days. In line with results from preclinical studies, nebulization of heparin was found to have an effect on systemic coagulation, but without causing systemic bleedings. Conclusion Local anticoagulant therapy through nebulization of anticoagulants attenuates pulmonary coagulopathy and frequently also inflammation in preclinical studies of lung injury. Recent human trials suggest nebulized heparin for ALI to be beneficial and safe, but data are very limited. PMID:22546487

  10. Reform in teaching preclinical pathophysiology.

    PubMed

    Li, Yong-Yu; Li, Kun; Yao, Hong; Xu, Xiao-Juan; Cai, Qiao-Lin

    2015-12-01

    Pathophysiology is a scientific discipline that studies the onset and progression of pathological conditions and diseases, and pathophysiology is one of the core courses in most preclinical medical curricula. In China, most medical schools house a Department of Pathophysiology, in contrast to medical schools in many developed countries. The staff in Chinese Departments of Pathophysiology generally consists of full-time instructors or lecturers who teach medical students. These lecturers are sometimes lacking in clinic knowledge and experiences. To overcome this, in recent years, we have been trying to bring new trends in teaching pathophysiology into our curriculum. Our purpose in writing this article was to share our experiences with our colleagues and peers worldwide in the hope that the insights we have gained in pathophysiology teaching will be of some value to educators who advocate teaching reform in medical schools. PMID:26628645

  11. The preclinical stage of spinocerebellar ataxias.

    PubMed

    Maas, Roderick P P W M; van Gaalen, Judith; Klockgether, Thomas; van de Warrenburg, Bart P C

    2015-07-01

    The autosomal dominant spinocerebellar ataxias (SCAs) are a heterogeneous group of degenerative diseases of the cerebellum and connected regions. The discovery of various SCA genes and the subsequent possibility of predictive testing currently allow a genetic diagnosis to be established years or even decades before the actual appearance of ataxia symptoms. A growing body of evidence, however, indicates that this preclinical stage is subject to the earliest pathophysiologic changes. This review article comprehensively summarizes the studies conducted in preclinical carriers of a mutation in one of the SCA genes. From these data, it can indeed be concluded that the preclinical phase in SCA is already characterized by detectable central and peripheral nervous system changes, which are reflected by subtle abnormalities during a careful clinical examination, changes in structural and functional brain imaging, abnormal neurophysiologic measurements, and/or altered motor learning paradigms. As these may be compensated for a long time, ataxia symptoms probably only appear after a certain threshold of dysfunction or degeneration has been exceeded. Detailed knowledge of this disease stage is of particular relevance for a better understanding of the pathogenesis of SCAs, will allow us to determine the optimal point in time for interventions in future therapeutic trials, and points to objective, valid biomarkers to assess disease progression. Further studies will benefit from a consensus-based definition of the preclinical stage, from using one and the same validated ataxia rating scale with one fixed cutoff value, and from applying similar mathematical models to calculate time to predicted disease onset. PMID:26062625

  12. Formulation and efficacy studies of new topical anesthetic creams.

    PubMed

    Kang, Lisheng; Jun, H W

    2003-05-01

    Local anesthetics (lidocaine or tetracaine) spontaneously melted at 25 degrees C when mixed with thymol and aqueous isopropyl alcohol solution (IPA) at proper ratios and formed novel two-phase melt systems (TMS). The TMS consisted of a homogeneous oil phase containing primarily a local anesthetic agent (lidocaine or tetracaine) and thymol, and a homogeneous aqueous phase containing primarily IPA and pH 9.2 buffer. The relationship between melting of the solid components and system composition was determined from the phase diagram obtained by a titration method. A select TMS of a local anesthetic agent (lidocaine or tetracaine) was directly emulsified to prepare an O/W cream and tested for the anesthetic efficacy on intact human skin. While both lidocaine (6%) and tetracaine (4%) creams were highly effective for dermal anesthesia with a similar onset time, the tetracaine cream exhibited a significantly longer duration of action than the lidocaine cream. An accelerated stability study indicated that lidocaine was significantly more stable than tetracaine in the creams. PMID:12779280

  13. System Vaccinology for the Evaluation of Influenza Vaccine Safety by Multiplex Gene Detection of Novel Biomarkers in a Preclinical Study and Batch Release Test

    PubMed Central

    Mizukami, Takuo; Momose, Haruka; Kuramitsu, Madoka; Takizawa, Kazuya; Araki, Kumiko; Furuhata, Keiko; Ishii, Ken J.; Hamaguchi, Isao; Yamaguchi, Kazunari

    2014-01-01

    Vaccines are beneficial and universal tools to prevent infectious disease. Thus, safety of vaccines is strictly evaluated in the preclinical phase of trials and every vaccine batch must be tested by the National Control Laboratories according to the guidelines published by each country. Despite many vaccine production platforms and methods, animal testing for safety evaluation is unchanged thus far. We recently developed a systems biological approach to vaccine safety evaluation where identification of specific biomarkers in a rat pre-clinical study evaluated the safety of vaccines for pandemic H5N1 influenza including Irf7, Lgals9, Lgalsbp3, Cxcl11, Timp1, Tap2, Psmb9, Psme1, Tapbp, C2, Csf1, Mx2, Zbp1, Ifrd1, Trafd1, Cxcl9, ?2m, Npc1, Ngfr and Ifi47. The current study evaluated whether these 20 biomarkers could evaluate the safety, batch-to-batch and manufacturer-to-manufacturer consistency of seasonal trivalent influenza vaccine using a multiplex gene detection system. When we evaluated the influenza HA vaccine (HAv) from four different manufactures, the biomarker analysis correlated to findings from conventional animal use tests, such as abnormal toxicity test. In addition, sensitivity of toxicity detection and differences in HAvs were higher and more accurate than with conventional methods. Despite a slight decrease in body weight caused by HAv from manufacturer B that was not statistically significant, our results suggest that HAv from manufacturer B is significantly different than the other HAvs tested with regard to Lgals3bp, Tapbp, Lgals9, Irf7 and C2 gene expression in rat lungs. Using the biomarkers confirmed in this study, we predicted batch-to-batch consistency and safety of influenza vaccines within 2 days compared with the conventional safety test, which takes longer. These biomarkers will facilitate the future development of new influenza vaccines and provide an opportunity to develop in vitro methods of evaluating batch-to-batch consistency and vaccine safety as an alternative to animal testing. PMID:25010690

  14. Evaluation of the clinical relevance and limitations of current pre-clinical models of peripheral artery disease.

    PubMed

    Krishna, Smriti Murali; Omer, Safraz Mohamed; Golledge, Jonathan

    2016-02-01

    Peripheral arterial disease (PAD) usually results from atherosclerosis and associated thrombosis and limits blood supply to the lower limbs. Common presenting symptoms include intermittent claudication (IC), rest pain and tissue loss. When limb viability is threatened, known as critical limb ischaemia (CLI), surgical and endovascular interventions are frequently undertaken; however, these are not always successful and ultimately major amputation may be required. There is significant interest in developing new therapeutic approaches to manage PAD which can be applied to patients unlikely to benefit from interventional approaches. Many of the therapeutic agents successful in inducing angiogenesis and arteriogenesis in pre-clinical animal models of PAD have failed to have efficacy in human randomized control trials. One possible reason for this inability to translate findings to patients could be the typeof pre-clinical animal models used. In the present review, we describe currently available pre-clinical models of PAD and discuss the advantages and disadvantages of the available models. A detailed assessment of the currently available pre-clinical animal models shows major limitations such as variability in the surgical procedure used to induce limb ischaemia, variability in the strains of rodents used, lack of risk factors incorporated into the model and lack of standardized functional outcomes. The most commonly used outcome assessments in studies within pre-clinical models differ from those employed in clinical trials within PAD patients. Most current pre-clinical models are designed to produce acute ischaemia which leads to muscle necrosis and inflammation. Patients, however, most commonly present with chronic ischaemia suggesting that more representative models are needed to evaluate therapeutic modalities that can be potentially translated to clinical practice. PMID:26678170

  15. Ultrasound guided fluorescence molecular tomography with improved quantification by an attenuation compensated born-normalization and in vivo preclinical study of cancer

    SciTech Connect

    Li, Baoqiang; Berti, Romain; Abran, Maxime; Lesage, Frédéric; Montreal Heart Institute, Montreal, Quebec H1T 1C8

    2014-05-15

    Ultrasound imaging, having the advantages of low-cost and non-invasiveness over MRI and X-ray CT, was reported by several studies as an adequate complement to fluorescence molecular tomography with the perspective of improving localization and quantification of fluorescent molecular targets in vivo. Based on the previous work, an improved dual-modality Fluorescence-Ultrasound imaging system was developed and then validated in imaging study with preclinical tumor model. Ultrasound imaging and a profilometer were used to obtain the anatomical prior information and 3D surface, separately, to precisely extract the tissue boundary on both sides of sample in order to achieve improved fluorescence reconstruction. Furthermore, a pattern-based fluorescence reconstruction on the detection side was incorporated to enable dimensional reduction of the dataset while keeping the useful information for reconstruction. Due to its putative role in the current imaging geometry and the chosen reconstruction technique, we developed an attenuation compensated Born-normalization method to reduce the attenuation effects and cancel off experimental factors when collecting quantitative fluorescence datasets over large area. Results of both simulation and phantom study demonstrated that fluorescent targets could be recovered accurately and quantitatively using this reconstruction mechanism. Finally, in vivo experiment confirms that the imaging system associated with the proposed image reconstruction approach was able to extract both functional and anatomical information, thereby improving quantification and localization of molecular targets.

  16. Preclinical study of SZ2080 material 3D microstructured scaffolds for cartilage tissue engineering made by femtosecond direct laser writing lithography.

    PubMed

    Mačiulaitis, Justinas; Deveikytė, Milda; Rekštytė, Sima; Bratchikov, Maksim; Darinskas, Adas; Šimbelytė, Agnė; Daunoras, Gintaras; Laurinavičienė, Aida; Laurinavičius, Arvydas; Gudas, Rimtautas; Malinauskas, Mangirdas; Mačiulaitis, Romaldas

    2015-01-01

    Over the last decade DLW employing ultrafast pulsed lasers has become a well-established technique for the creation of custom-made free-form three-dimensional (3D) microscaffolds out of a variety of materials ranging from proteins to biocompatible glasses. Its potential applications for manufacturing a patient's specific scaffold seem unlimited in terms of spatial resolution and geometry complexity. However, despite few exceptions in which live cells or primitive organisms were encapsulated into a polymer matrix, no demonstration of an in vivo study case of scaffolds generated with the use of such a method was performed. Here, we report a preclinical study of 3D artificial microstructured scaffolds out of hybrid organic-inorganic (HOI) material SZ2080 fabricated using the DLW technique. The created 2.1 × 2.1 × 0.21 mm(3) membrane constructs are tested both in vitro by growing isolated allogeneic rabbit chondrocytes (Cho) and in vivo by implanting them into rabbit organisms for one, three and six months. An ex vivo histological examination shows that certain pore geometry and the pre-growing of Cho prior to implantation significantly improves the performance of the created 3D scaffolds. The achieved biocompatibility is comparable to the commercially available collagen membranes. The successful outcome of this study supports the idea that hexagonal-pore-shaped HOI microstructured scaffolds in combination with Cho seeding may be successfully implemented for cartilage tissue engineering. PMID:25797444

  17. Preclinical Cardiorenal Interrelationships in Essential Hypertension

    PubMed Central

    Tsioufis, Costas; Tsiachris, Dimitrios; Kasiakogias, Alexandros; Dimitriadis, Kyriakos; Petras, Dimitris; Goumenos, Dimitris; Siamopoulos, Konstantinos; Stefanadis, Christodoulos

    2013-01-01

    A diseased heart causes numerous adverse effects on kidney function, and vice versa renal disease can significantly impair cardiac function. Beyond these heart-kidney interrelationships at the clinical level, a reciprocal association has been suggested to exist even in the early stages of those organs' dysfunction. The aim of the present review is to provide evidence of the presence of a preclinical cardiorenal syndrome in the particular setting of essential hypertension, focusing on the subsequent hypertensive sequelae on heart and kidneys. In particular, a plethora of studies have demonstrated not only the predictive role of kidney damage, as expressed by either decreased glomerular filtration or increased urine albumin excretion, for adverse left ventricular functional and structural adaptations but also preclinical heart disease, i.e. left ventricular hypertrophy that is associated with deterioration of renal function. Notably, these reciprocal interactions seem to exist even at the level of microcirculation, since both coronary flow reserve and renal hemodynamics are strongly related with clinical and preclinical renal and cardiac damage, respectively. In this preclinical setting, common pathophysiological denominators, including the increased hemodynamic load, sympathetic and renin-angiotensin system overactivity, increased subclinical inflammatory reaction, and endothelial dysfunction, account not only for the reported associations between overt cardiac and renal damage but also for the parallel changes that occur in coronary and renal microcirculation. PMID:23946723

  18. Preclinical Pharmacological Approaches in Drug Discovery for Chronic Pain.

    PubMed

    Whiteside, Garth T; Pomonis, James D; Kennedy, Jeffrey D

    2016-01-01

    In recent years, animal behavioral models, particularly those used in pain research, have been increasingly scrutinized and criticized for their role in the poor translation of novel pharmacotherapies for chronic pain. This chapter addresses the use of animal models of pain used in drug discovery research. It highlights how, when, and why animal models of pain are used as one of the many experimental tools used to gain better understanding of target mechanisms and rank-order compounds in the iterative process of establishing structure-activity relationship. Together, these models help create an "analgesic signature" for a compound and inform the indications most likely to yield success in clinical trials. In addition, the authors discuss some often underappreciated aspects of currently used (traditional) animal models of pain, including simply applying basic pharmacological principles to study design and data interpretation as well as consideration of efficacy alongside side effect measures as part of the overall conclusion of efficacy. This is provided to add perspective regarding current efforts to develop new models and endpoints both in rodents and in larger animal species as well as assess cognitive and/or affective aspects of pain. Finally, the authors suggest ways in which efficacy evaluation in animal models of pain, whether traditional or new, might better align with clinical standards of analysis, citing examples where applying effect size and number needed to treat estimations to animal model data suggest that the efficacy bar often may be set too low preclinically to allow successful translation to the clinical setting. PMID:26920017

  19. Transformational and transactional leadership and exercise-related self-efficacy: an exploratory study.

    PubMed

    Beauchamp, Mark R; Welch, Amy S; Hulley, Angie J

    2007-01-01

    The purpose of this study was to examine the relationships between transformational and transactional leadership behaviors and the self-efficacy ofparticipants involved in a structured 10-week exercise program. Three weeksinto their exercise classes 174 females (M age = 25.36 years, SD = 8.48) provided ratings of their exercise instructor's leadership behaviors as well as their personal efficacy related to scheduling, over-coming barriers and within-class capabilities. Results revealed that for exercise initiates, contingent rewards behaviors were able to explain unique variation in scheduling self-efficacy and barrier self-efficacy, but not within-class self-efficacy. For experienced exercisers, none of the leadership behaviors assessed in this study were associated with participant self-efficacy. PMID:17158842

  20. Non-invasive molecular imaging for preclinical cancer therapeutic development

    PubMed Central

    O'Farrell, AC; Shnyder, SD; Marston, G; Coletta, PL; Gill, JH

    2013-01-01

    Molecular and non-invasive imaging are rapidly emerging fields in preclinical cancer drug discovery. This is driven by the need to develop more efficacious and safer treatments, the advent of molecular-targeted therapeutics, and the requirements to reduce and refine current preclinical in vivo models. Such bioimaging strategies include MRI, PET, single positron emission computed tomography, ultrasound, and optical approaches such as bioluminescence and fluorescence imaging. These molecular imaging modalities have several advantages over traditional screening methods, not least the ability to quantitatively monitor pharmacodynamic changes at the cellular and molecular level in living animals non-invasively in real time. This review aims to provide an overview of non-invasive molecular imaging techniques, highlighting the strengths, limitations and versatility of these approaches in preclinical cancer drug discovery and development. PMID:23488622

  1. A rapid and sensitive LC-MS/MS assay for the quantitation of deacetyl mycoepoxydiene in rat plasma with application to preclinical pharmacokinetics studies.

    PubMed

    Gao, Yanhui; Xu, Jiangbo; Xu, Jiaxing; Huang, Yaojian; Shen, Yuemao; Liu, ZhaoPing

    2012-01-01

    The purpose of this study was to develop and validate a high-performance liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method for analysis of the deacetyl mycoepoxydiene in rat plasma. The analyte and internal standard (I.S.), benorilate, were extracted from rat plasma by precipitation protein and separated on a C(18) column using acetonitrile-0.5% formic acid as mobile phase. Detection was performed using a turbo-spray ionization source and mass spectrometric positive multi-reaction-monitoring-mode (+MRM) at an ion voltage of +4800 V. The assay was linear over the concentration range 5-5000 ng/mL with the lowest limit of quantification (LLOQ) of 5 ng/mL. The method also afforded satisfactory results in terms of the sensitivity, specificity, precision (intra- and inter-day, RSD<5.8%), accuracy, recovery as well as the stability of the analyte under various conditions. The method was successfully applied to a preclinical pharmacokinetic study in rats after a single intravenous administration of deacetyl mycoepoxydiene 10 mg/kg. PMID:22169059

  2. Rapid and sensitive ultra-high-pressure liquid chromatography method for quantification of antichagasic benznidazole in plasma: application in a preclinical pharmacokinetic study.

    PubMed

    Davano, Marcelo Gomes; de Campos, Michel Leandro; Peccinini, Rosngela Gonalves

    2015-07-01

    Benznidazole (BNZ) and nifurtimox are the only drugs available for treating Chagas disease. In this work, we validated a bioanalytical method for the quantification of BNZ in plasma aimed at improving sensitivity and time of analysis compared with the assays already published. Furthermore, we demonstrated the application of the method in a preclinical pharmacokinetic study after administration of a single oral dose of BNZ in Wistar rats. A Waters Acquity UHPLC system equipped with a UV-vis detector was employed. The method was established using an Acquity UHPLC HSS SB C18 protected by an Acquity UHPLC HSS SB C18 VanGuard guard column and detection at 324 nm. The mobile phase consisted of ultrapure water-acetonitrile (65:35), and elution was isocratic. The mobile phase flow rate was 0.55 mL/min, the volume of injection was 1 ?L, and the run time was just 2 min. The samples were kept at 25C until injection and the column at 45C for the chromatographic separation. The sample preparation was performed by a rapid protein precipitation with acetonitrile. The linear concentration range was 0.15-20 g/mL. The pharmacokinetic parameters of BNZ in rats were determined and the method was considered sensitive, fast and suitable for application in pharmacokinetic studies. PMID:25424984

  3. A Study Investigating Relationships between Elementary Principals' and Teachers' Self-Efficacy and Student Achievement

    ERIC Educational Resources Information Center

    Domsch, Gayle D.

    2009-01-01

    In order to examine effective behaviors and efficacy, this study examined the relationships between the self-reflection of effective practices by principals and teachers, as assessed by self-efficacy scales, and student achievement, as evaluated by the state assessment program. Other studies determined that effective behaviors preceded and

  4. A Study of Efficacy and Professional Development among Alternatively-Certified Teachers in Arizona

    ERIC Educational Resources Information Center

    Ludlow, Carlyn

    2010-01-01

    The purpose of this descriptive and comparative study was to investigate the self-assessed efficacy levels of alternatively-certified teachers in Arizona. More specifically, this study examined the teachers' perceived ability to influence student learning and the extent to which, if at all, their self-reported efficacy levels differed based on the…

  5. 21 CFR 201.200 - Disclosure of drug efficacy study evaluations in labeling and advertising.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Disclosure of drug efficacy study evaluations in labeling and advertising. 201.200 Section 201.200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING Labeling Claims for Drugs in Drug Efficacy Study 201.200 Disclosure of...

  6. Efficacy of Counseling and Psychotherapy in Schools: A Meta-Analytic Review of Treatment Outcome Studies

    ERIC Educational Resources Information Center

    Baskin, Thomas W.; Slaten, Christopher D.; Crosby, Nicole R.; Pufahl, Tiffany; Schneller, Cali L.; Ladell, Monica

    2010-01-01

    This study investigated the efficacy of counseling and psychotherapy interventions for youth in schools. Data were examined for 107 studies that included 132 treatment interventions. Overall efficacy was d = 0.45 and was significantly different from zero. Interventions for adolescents outperformed those of children, treatment groups that were…

  7. A Study on the Relationship between Teacher Self Efficacy and Burnout

    ERIC Educational Resources Information Center

    Savas, Ahmet Cezmi; Bozgeyik, Yunus; Eser, Ismail

    2014-01-01

    The major purpose of the study was to examine the relationship between teacher self efficacy and burnout. In order to collect the related data, "Maslach Burnout Inventory" and "Teacher Sense of Efficacy Scale" were used. The sample of the study consisted of 163 randomly chosen teachers who worked in various primary and

  8. Efficacy of Counseling and Psychotherapy in Schools: A Meta-Analytic Review of Treatment Outcome Studies

    ERIC Educational Resources Information Center

    Baskin, Thomas W.; Slaten, Christopher D.; Crosby, Nicole R.; Pufahl, Tiffany; Schneller, Cali L.; Ladell, Monica

    2010-01-01

    This study investigated the efficacy of counseling and psychotherapy interventions for youth in schools. Data were examined for 107 studies that included 132 treatment interventions. Overall efficacy was d = 0.45 and was significantly different from zero. Interventions for adolescents outperformed those of children, treatment groups that were

  9. Clinical Self-Efficacy in Senior Nursing Students: A Mixed- Methods Study

    PubMed Central

    Abdal, Marzieh; Masoudi Alavi, Negin; Adib-Hajbaghery, Mohsen

    2015-01-01

    Background: Clinical education has a basic role in nursing education, and effective clinical training establishes a sense of clinical self-efficacy in senior nursing students. Self-efficacy is a key component for acting independently in the nursing profession. Objectives: This study was designed to outline senior nursing students’ views about clinical self-efficacy and to determine its level in nursing students. Patients and Methods: A mixed-methods approach, including a quantitative cross-sectional study and qualitative content analysis,was used in this study. Participants were senior nursing students who were in their two last semesters. During the initial quantitative stage, all students in the 7th and 8th semesters of the nursing major were invited to participate. They were asked to complete the Nursing Clinical Self-Efficacy Scale (NCSES) and, during the subsequent qualitative stage, the 14 students in the 7th and 8th semesters were asked to participate in semi-structured interviews. Results: In the quantitative part, 58 students completed the self-efficacy questionnaire; the mean score was 219.28 ± 35.8, which showed moderate self-efficacy in students. Self-efficacy was different across skills. In the qualitative part, the 355 open codes that were extracted from the interviews were clustered to 12 categories and 3 themes. The main themes included the factors related to self-efficacy, outcomes of self-efficacy, and ways to improve self-efficacy. Conclusions: Students had moderate self-efficacy. Several factors such as environment, nursing colleagues, and clinical educators could influence the creation of clinical self-efficacy in nursing students. PMID:26576443

  10. Comparative in vitro efficacy of antimicrobial shampoos: a pilot study.

    PubMed

    Young, Rebecca; Buckley, Laura; McEwan, Neil; Nuttall, Tim

    2012-02-01

    This study compared the antimicrobial efficacy of shampoos against meticillin-sensitive Staphylococcus pseudintermedius (MSSP), meticillin-resistant S. pseudintermedius (MRSP), antibiotic-sensitive Pseudomonas aeruginosa (PA), multidrug-resistant P. aeruginosa (MDR-PA) and Malassezia pachydermatis. Three isolates were incubated for 10, 30 and 60 min with each shampoo diluted in phosphate-buffered saline. Aliquots were then incubated for 16-18 h on sheep blood agar (bacteria) or for 3 days on Sabouraud's dextrose agar (Malassezia). The minimal bactericidal concentrations (MBCs) for chlorhexidine products (Malaseb(), Pyoderm()/Microbex() and Hibiscrub()) were 1:1,024-1:2,048 for MSSP and MRSP, 1:512-1:1,024 for PA and MDR-PA, and 1:2,048-1:5,096 for Malassezia at all time points. The MBCs for benzoyl peroxide (Paxcutol()) for MSSP and MRSP were 1:2-1:8 at 10 min, and 1:256 after 30 and 60 min. A 1:2 dilution was effective against Pseudomonas, and 1:512-1:1,024 dilutions were effective against Malassezia at all time points. The MBCs for ethyl lactate (Etiderm()) for MSSP and MRSP were 1:2 at 10 min, and 1:2-1:16 after 30 and 60 min. A 1:2 dilution was effective against Pseudomonas, and a 1:512 dilution was effective against Malassezia at all time points. Chloroxylenol (Coatex()) and acetic acid-boric acid (Malacetic()) were not effective against MSSP, MRSP or Pseudomonas. Both were effective against Malassezia at 1:8-1:16 dilution at 10 min, and at 1:8-1:32 dilution after 30 and 60 min. In conclusion, chlorhexidine appeared to be the most effective topical biocide, and MRSP and MDR-PA were no less susceptible than antibiotic-sensitive organisms. These results should, however, be confirmed with larger numbers of isolates. PMID:21777309

  11. Preclinical Evaluation of the Immunomodulatory Properties of Cardiac Adipose Tissue Progenitor Cells Using Umbilical Cord Blood Mesenchymal Stem Cells: A Direct Comparative Study

    PubMed Central

    Perea-Gil, Isaac; Mongui-Tortajada, Marta; Glvez-Montn, Carolina; Bayes-Genis, Antoni; Borrs, Francesc E.; Roura, Santiago

    2015-01-01

    Cell-based strategies to regenerate injured myocardial tissue have emerged over the past decade, but the optimum cell type is still under scrutiny. In this context, human adult epicardial fat surrounding the heart has been characterized as a reservoir of mesenchymal-like progenitor cells (cardiac ATDPCs) with potential clinical benefits. However, additional data on the possibility that these cells could trigger a deleterious immune response following implantation are needed. Thus, in the presented study, we took advantage of the well-established low immunogenicity of umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) to comparatively assess the immunomodulatory properties of cardiac ATDPCs in an in vitro allostimulatory assay using allogeneic mature monocyte-derived dendritic cells (MDDCs). Similar to UCBMSCs, increasing amounts of seeded cardiac ATDPCs suppressed the alloproliferation of T cells in a dose-dependent manner. Secretion of proinflammatory cytokines (IL6, TNF?, and IFN?) was also specifically modulated by the different numbers of cardiac ATDPCs cocultured. In summary, we show that cardiac ATDPCs abrogate T cell alloproliferation upon stimulation with allogeneic mature MDDCs, suggesting that they could further regulate a possible harmful immune response in vivo. Additionally, UCBMSCs can be considered as valuable tools to preclinically predict the immunogenicity of prospective regenerative cells. PMID:25861626

  12. Transplantation of umbilical cord-derived mesenchymal stem cells as a novel strategy to protect the central nervous system: technical aspects, preclinical studies, and clinical perspectives.

    PubMed

    Dalous, Jrmie; Larghero, Jrome; Baud, Olivier

    2012-04-01

    The prevention of perinatal neurological disabilities remains a major challenge for public health, and no neuroprotective treatment to date has proven clinically useful in reducing the lesions leading to these disabilities. Efforts are, therefore, urgently needed to test other neuroprotective strategies including cell therapies. Although stem cells have raised great hopes as an inexhaustible source of therapeutic products that could be used for neuroprotection and neuroregeneration in disorders affecting the brain and spinal cord, certain sources of stem cells are associated with potential ethical issues. The human umbilical cord (hUC) is a rich source of stem and progenitor cells including mesenchymal stem cells (MSCs) derived either from the cord or from cord blood. hUC MSCs (hUC-MSCs) have several advantages as compared to other types and sources of stem cells. In this review, we will summarize the most recent findings regarding the technical aspects and the preclinical investigation of these promising cells in neuroprotection and neuroregeneration, and their potential use in the developing human brain. However, extensive studies are needed to optimize the administration protocol, safety parameters, and potential preinjection cell manipulations before designing a controlled trial in human neonates. PMID:22430384

  13. Preclinical Dose-Finding Study With a Liver-Tropic, Recombinant AAV-2/8 Vector in the Mouse Model of Galactosialidosis

    PubMed Central

    Hu, Huimin; Gomero, Elida; Bonten, Erik; Gray, John T; Allay, Jim; Wu, Yanan; Wu, Jianrong; Calabrese, Christopher; Nienhuis, Arthur; d'Azzo, Alessandra

    2012-01-01

    Galactosialidosis (GS) is a lysosomal storage disease linked to deficiency of the protective protein/cathepsin A (PPCA). Similarly to GS patients, Ppca-null mice develop a systemic disease of the reticuloendothelial system, affecting most visceral organs and the nervous system. Symptoms include severe nephropathy, visceromegaly, infertility, progressive ataxia, and shortened life span. Here, we have conducted a preclinical, dose-finding study on a large cohort of GS mice injected intravenously at 1 month of age with increasing doses of a GMP-grade rAAV2/8 vector, expressing PPCA under the control of a liver-specific promoter. Treated mice, monitored for 16 weeks post-treatment, had normal physical appearance and behavior without discernable side effects. Despite the restricted expression of the transgene in the liver, immunohistochemical and biochemical analyses of other systemic organs, serum, and urine showed a dose-dependent, widespread correction of the disease phenotype, suggestive of a protein-mediated mechanism of cross-correction. A notable finding was that rAAV-treated GS mice showed high expression of PPCA in the reproductive organs, which resulted in reversal of their infertility. Together these results support the use of this rAAV-PPCA vector as a viable and safe method of gene delivery for the treatment of systemic disease in non-neuropathic GS patients. PMID:22008912

  14. Use of 'dilute-and-shoot' liquid chromatography-high resolution mass spectrometry in preclinical research: application to a DMPK study of perhexiline in mouse plasma.

    PubMed

    Esposito, Simone; Bracacel, Elena; Nibbio, Martina; Speziale, Roberto; Orsatti, Laura; Veneziano, Maria; Monteagudo, Edith; Bonelli, Fabio

    2016-01-25

    This work describes a simple, sensitive and rapid liquid chromatography-high resolution mass spectrometry method for the quantitation of perhexiline and the simultaneous detection of perhexiline metabolites in C57bl/6 mice plasma. Only 5?L of plasma was used for analysis. Pretreatment was limited to a 100-fold dilution ('dilute-and-shoot'). The analyte was detected by high resolution mass spectrometry (Orbitrap technology). Three scan events were performed over the entire chromatogram. Targeted single ion monitoring with data dependent acquisition was employed for perhexiline quantitation and confirmation, while full scan was used to perform untargeted detection of perhexiline phase I and phase II circulating metabolites. The calibration curve was linear (r(2)=0.990) ranging from 0.305ng/mL (LLOQ) to 10000ng/mL. Matrix effect was limited to 6.1%. The method was applied to a pharmacokinetic study of perhexiline in mouse plasma and the results obtained were compared to a standard sample preparation method based on protein precipitation and liquid chromatography-tandem mass spectrometry (MRM mode) detection. The new approach provided comparable results in terms of pharmacokinetics parameters estimate with a high sensitivity, additional information on perhexiline circulating metabolites and a low consumption of biological sample. The combination of the 'dilute-and-shoot' approach together with HRMS targeted and untargeted detection represents a suitable alternative to classic bioanalytical approaches in preclinical research. PMID:26517851

  15. Preclinical evaluation of the immunomodulatory properties of cardiac adipose tissue progenitor cells using umbilical cord blood mesenchymal stem cells: a direct comparative study.

    PubMed

    Perea-Gil, Isaac; Mongui-Tortajada, Marta; Glvez-Montn, Carolina; Bayes-Genis, Antoni; Borrs, Francesc E; Roura, Santiago

    2015-01-01

    Cell-based strategies to regenerate injured myocardial tissue have emerged over the past decade, but the optimum cell type is still under scrutiny. In this context, human adult epicardial fat surrounding the heart has been characterized as a reservoir of mesenchymal-like progenitor cells (cardiac ATDPCs) with potential clinical benefits. However, additional data on the possibility that these cells could trigger a deleterious immune response following implantation are needed. Thus, in the presented study, we took advantage of the well-established low immunogenicity of umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) to comparatively assess the immunomodulatory properties of cardiac ATDPCs in an in vitro allostimulatory assay using allogeneic mature monocyte-derived dendritic cells (MDDCs). Similar to UCBMSCs, increasing amounts of seeded cardiac ATDPCs suppressed the alloproliferation of T cells in a dose-dependent manner. Secretion of proinflammatory cytokines (IL6, TNF?, and IFN?) was also specifically modulated by the different numbers of cardiac ATDPCs cocultured. In summary, we show that cardiac ATDPCs abrogate T cell alloproliferation upon stimulation with allogeneic mature MDDCs, suggesting that they could further regulate a possible harmful immune response in vivo. Additionally, UCBMSCs can be considered as valuable tools to preclinically predict the immunogenicity of prospective regenerative cells. PMID:25861626

  16. Autofluorescence imaging device for real-time detection and tracking of pathogenic bacteria in a mouse skin wound model: preclinical feasibility studies

    NASA Astrophysics Data System (ADS)

    Wu, Yichao Charlie; Kulbatski, Iris; Medeiros, Philip J.; Maeda, Azusa; Bu, Jiachuan; Xu, Lizhen; Chen, Yonghong; DaCosta, Ralph S.

    2014-08-01

    Bacterial infection significantly impedes wound healing. Clinical diagnosis of wound infections is subjective and suboptimal, in part because bacteria are invisible to the naked eye during clinical examination. Moreover, bacterial infection can be present in asymptomatic patients, leading to missed opportunities for diagnosis and treatment. We developed a prototype handheld autofluorescence (AF) imaging device (Portable Real-time Optical Detection, Identification and Guidance for Intervention-PRODIGI) to noninvasively visualize and measure bacterial load in wounds in real time. We conducted preclinical pilot studies in an established nude mouse skin wound model inoculated with bioluminescent Staphylococcus aureus bacteria. We tested the feasibility of longitudinal AF imaging for in vivo visualization of bacterial load in skin wounds, validated by bioluminescence imaging. We showed that bacteria (S. aureus), occult to standard examination, can be visualized in wounds using PRODIGI. We also detected quantitative changes in wound bacterial load over time based on the antibiotic treatment and the correlation of bacterial AF intensity with bacterial load. AF imaging of wounds offers a safe, noninvasive method for visualizing the presence, location, and extent of bacteria as well as measuring relative changes in bacterial load in wounds in real time.

  17. Preclinical Neonatal Rat Studies of Heparin-Binding EGF-Like Growth Factor in Protection of the Intestines From Necrotizing Enterocolitis

    PubMed Central

    RADULESCU, ANDREI; ZORKO, NICHOLAS A.; YU, XIAOYI; BESNER, GAIL E.

    2013-01-01

    We have previously demonstrated that enterally administered heparin-binding EGF-like growth factor (HB-EGF) produced in Escherichia coli decreases the incidence and severity of intestinal injury in a neonatal rat model of necrotizing enterocolitis (NEC). In preparation for upcoming human clinical trials, large-scale production of HB-EGF according to Good Manufacturing Practice (GMP) has been successfully accomplished using a Pichia pastoris yeast system. The current studies used a neonatal rat model of NEC to elucidate several important preclinical characteristics of HB-EGF therapy. We found that enteral administration of HB-EGF (800 ?g/kg/dose) four times a day effectively reduced the incidence and severity of NEC, that Pichia-derived HB-EGF was not significantly different from E. coli-derived HB-EGF in preventing NEC, that EGF was not superior to HB-EGF in preventing NEC, and that prophylactic administration of HB-EGF added to formula starting with the first feed or 12 h later significantly reduced the incidence of NEC, with no change in the incidence of NEC noted if HB-EGF was added to the formula starting 24, 48, or 72 h after birth. Thus, large-scale production of GMP-grade HB-EGF in Pichia pastoris yeast produces a biologically active molecule suitable for human clinical trials. PMID:19127210

  18. An Exploratory Study into the Efficacy of Learning Objects

    ERIC Educational Resources Information Center

    Farha, Nicholas W.

    2009-01-01

    Learning objects have quickly become a widely accepted approach to instructional technology, particularly in on-line and computer-based learning environments. While there is a substantial body of literature concerning learning objects, very little of it verifies their efficacy. This research investigated the effectiveness of learning objects by

  19. Impact of Simulation and Clinical Experience on Self-efficacy in Nursing Students: Intervention Study.

    PubMed

    Kimhi, Einat; Reishtein, Judith L; Cohen, Miri; Friger, Michael; Hurvitz, Nancy; Avraham, Rinat

    2016-01-01

    This study compared the effect of simulation and clinical experience timing on self-confidence/self-efficacy for the nursing process. Using a randomized, double-crossover design, self-efficacy was measured 3 times. Although self-efficacy was significantly higher at time 1 for students who had clinical experience, there was no difference between the groups at the end of the course (time 2). Thus, simulation increased self-confidence/self-efficacy equivalently if placed either before or after clinical experience. PMID:26218009

  20. The Preclinical Alzheimer Cognitive Composite

    PubMed Central

    Donohue, Michael C.; Sperling, Reisa A.; Salmon, David P.; Rentz, Dorene M.; Raman, Rema; Thomas, Ronald G.; Weiner, Michael; Aisen, Paul S.

    2015-01-01

    IMPORTANCE As Alzheimer disease (AD) research moves to intervene in presymptomatic phases of the disease, we must develop outcome measures sensitive to the earliest disease-related changes. OBJECTIVE To demonstrate the feasibility of a cognitive composite outcome for clinically normal elderly participants with evidence of AD pathology using the ADCS Preclinical Alzheimer Cognitive Composite (ADCS-PACC). The ADCS-PACC combines tests that assess episodic memory, timed executive function, and global cognition. The ADCS-PACC is the primary outcome measure for the first clinical trial in preclinical AD (ie, the Anti-Amyloid Treatment in Asymptomatic Alzheimer’s study). DESIGN, SETTING, AND PARTICIPANTS With the ADCS-PACC, we derive pilot estimates of amyloid-related decline using data from 2 observational studies conducted in North America and another conducted in Australia. The participants analyzed had normal cognition and mean ages of 75.81, 71.37, and 79.42 years across the 3 studies. MAIN OUTCOMES AND MEASURES For the 2 studies that collected data on Aβ levels (ADNI and AIBL), we estimate decline in a preclinical AD “Aβ-positive” placebo group and compare them with an “Aβ-negative” group. For the study that did not include data on Aβ levels (the ADCS Prevention Instrument [ADCS-PI] study), we grouped participants by the presence of APOE-ɛ4 and by clinical progression. RESULTS In ADNI, Aβ-positive participants showed more decline than did Aβ-negative participants with regard to the ADCS-PACC score at 24 months (mean [SE] difference, −1.239 [0.522] [95% CI, −2.263 to −0.215]; P = .02). In AIBL, the mean (SE) difference is significant at both 18 months (−1.009 [0.406] [95% CI, −1.805 to −0.213]; P = .01) and 36 months (−1.404 [0.452] [95% CI, −2.290 to −0.519]; P = .002). In the ADCS-PI study, APOE-ɛ4 allele carriers performed significantly worse on the ADCS-PACC at 24 months (mean [SE] score, −0.742 [0.294] [95% CI, −1.318 to −0.165]; P = .01) and 36 months (−1.531 [0.469] [95% CI, −2.450 to −0.612]; P = .001). In the ADCS-PI study, cognitively normal participants who progress from a global Clinical Dementia Rating score of 0 are significantly worse on the ADCS-PACC than cognitively normal participants who are stable with a global Clinical Dementia Rating score of 0 at months 12, 24, and 36 (mean [SE] ADCS-PACC score, −4.471 [0.702] [95% CI, −5.848 to −3.094]; P < .001). Using pilot estimates of variance and assuming 500 participants per group with 30% attrition and a 5% α level, we project 80% power to detect effects in the range of Δ = 0.467 to 0.733 on the ADCS-PACC. CONCLUSIONS AND RELEVANCE Analyses of at-risk cognitively normal populations suggest that we can reliably measure the first signs of cognitive decline with the ADCS-PACC. These analyses also suggest the feasibility of secondary prevention trials. PMID:24886908

  1. Target-directed development and preclinical characterization of the proposed biosimilar rituximab GP2013

    PubMed Central

    Kronthaler, Ulrich; Koppenburg, Vera; Fink, Martin; Meyer, Ines; Papandrikopoulou, Anastassia; Hofmann, Matthias; Stangler, Thomas; Visser, Jan

    2014-01-01

    Biosimilar development involves a target-directed iterative process to ensure a similar product to the originator. Here we report the preclinical development of the proposed biosimilar rituximab (GP2013). Post-translational modifications and bioactivities of GP2013 versus originator rituximab were engineered and monitored to ensure similar pharmacological profiles. Antibody-dependent cellular cytotoxicity (ADCC) was used to illustrate how different glycosylation patterns and structurefunction relationships were controlled during process development. Pharmacological comparability between GP2013 and originator rituximab were confirmed in preclinical studies using clinical scale drug product. Similar in vitro ADCC potency was demonstrated when compared in a doseresponse manner against two lymphoma cell lines using freshly purified human natural killer (NK) cells. In vivo efficacy was demonstrated in two well characterized mouse xenograft models, testing at sensitive sub-therapeutic dose levels. Pharmacokinetics and pharmacodynamics (CD20 cell depletion) were likewise comparable in cynomolgus monkeys. This preclinical comparability exercise confirms that GP2013 and originator rituximab are pharmacologically similar. PMID:24024472

  2. A Novel Aminotetralin-Type Serotonin (5-HT) 2C Receptor-Specific Agonist and 5-HT2A Competitive Antagonist/5-HT2B Inverse Agonist with Preclinical Efficacy for Psychoses

    PubMed Central

    Morgan, Drake; Felsing, Daniel; Kondabolu, Krishnakanth; Rowland, Neil E.; Robertson, Kimberly L.; Sakhuja, Rajeev; Booth, Raymond G.

    2014-01-01

    Development of 5-HT2C agonists for treatment of neuropsychiatric disorders, including psychoses, substance abuse, and obesity, has been fraught with difficulties, because the vast majority of reported 5-HT2C selective agonists also activate 5-HT2A and/or 5-HT2B receptors, potentially causing hallucinations and/or cardiac valvulopathy. Herein is described a novel, potent, and efficacious human 5-HT2C receptor agonist, (?)-trans-(2S,4R)-4-(3?[meta]-bromophenyl)-N,N-dimethyl-1,2,3,4-tetrahydronaphthalen-2-amine (?)-MBP), that is a competitive antagonist and inverse agonist at human 5-HT2A and 5-HT2B receptors, respectively. (?)-MBP has efficacy comparable to the prototypical second-generation antipsychotic drug clozapine in three C57Bl/6 mouse models of drug-induced psychoses: the head-twitch response elicited by [2,5]-dimethoxy-4-iodoamphetamine; hyperlocomotion induced by MK-801 [(5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (dizocilpine maleate)]; and hyperlocomotion induced by amphetamine. (?)-MBP, however, does not alter locomotion when administered alone, distinguishing it from clozapine, which suppresses locomotion. Finally, consumption of highly palatable food by mice was not increased by (?)-MBP at a dose that produced at least 50% maximal efficacy in the psychoses models. Compared with (?)-MBP, the enantiomer (+)-MBP was much less active across in vitro affinity and functional assays using mouse and human receptors and also translated in vivo with comparably lower potency and efficacy. Results indicate a 5-HT2C receptor-specific agonist, such as (?)-MBP, may be pharmacotherapeutic for psychoses, without liability for obesity, hallucinations, heart disease, sedation, or motoric disorders. PMID:24563531

  3. A Qualitative Case Study Exploring Self-Efficacy and Its Influence on Fourth Grade Mathematics Students

    ERIC Educational Resources Information Center

    Prindle, Catherine M.

    2014-01-01

    The perception of higher self-efficacy in young children has been determined to be a better predictor of intellectual and academic performance than simply the acquisition of skills alone. This empirical qualitative single-case study was conducted in order to explore the influence of self-efficacy instruction on perceptions toward and achievement

  4. Organizational Structure, Collegial Trust, and College Faculty Teaching Efficacy: A Case Study

    ERIC Educational Resources Information Center

    Okpogba, Desmond

    2011-01-01

    The purpose of this mixed-method study was to explore the relationship between faculty self-efficacy, organizational structure, and collegial trust. The concepts of teacher self-efficacy, organizational structure, and collegial trust were used to investigate any possible empirical relationships existing between these variables in a private,

  5. Developing Teaching Self-Efficacy in Research Institutions: A Study of Award-Winning Professors

    ERIC Educational Resources Information Center

    Morris, David B.; Usher, Ellen L.

    2011-01-01

    The purpose of this study was to assess the sources of award-wining research professors' (six women; six men) teaching self-efficacy through the framework of Bandura's (1986) social cognitive theory. Semi-structured interviews revealed that mastery experiences and social persuasions were particularly influential sources of self-efficacy and that…

  6. Factors Influencing Teachers' Technology Self-Efficacy: A Case Study

    ERIC Educational Resources Information Center

    Farah, Amy Caroline

    2012-01-01

    Factors influencing teachers' levels of technology self-efficacy were examined through a qualitative multi-site, multi-subject case study research design. An initial survey was administered to all full-time, certified teachers at three school sites in order to gauge teachers' current level of technology self-efficacy. From that

  7. Emotional Intelligence and Teacher Efficacy: A Study of Turkish EFL Pre-Service Teachers

    ERIC Educational Resources Information Center

    Kocoglu, Zeynep

    2011-01-01

    This study investigated the relationship between emotional intelligence and teacher efficacy among 90 English language pre-service teachers from a university in Turkey. Data sources included Tschannen-Moran and Woolfolk-Hoy's Teachers' Sense of Efficacy Scale and Reuven Bar-On's Emotional Quotient Inventory. The findings indicated that Turkish EFL

  8. Education for Sustainability: A Case Study of Preservice Primary Teachers' Knowledge and Efficacy

    ERIC Educational Resources Information Center

    Effeney, Gerard; Davis, Julie

    2013-01-01

    This study investigated the relationships between knowledge and efficacy for teaching sustainability in a sample of 266 pre-service primary teachers at a large, metropolitan university in Australia. A survey gathered information about the participant's attitudes and self-efficacy for education for sustainability, along with their perceived…

  9. A Qualitative Case Study Exploring Self-Efficacy and Its Influence on Fourth Grade Mathematics Students

    ERIC Educational Resources Information Center

    Prindle, Catherine M.

    2014-01-01

    The perception of higher self-efficacy in young children has been determined to be a better predictor of intellectual and academic performance than simply the acquisition of skills alone. This empirical qualitative single-case study was conducted in order to explore the influence of self-efficacy instruction on perceptions toward and achievement…

  10. Emotional Intelligence and Teacher Efficacy: A Study of Turkish EFL Pre-Service Teachers

    ERIC Educational Resources Information Center

    Kocoglu, Zeynep

    2011-01-01

    This study investigated the relationship between emotional intelligence and teacher efficacy among 90 English language pre-service teachers from a university in Turkey. Data sources included Tschannen-Moran and Woolfolk-Hoy's Teachers' Sense of Efficacy Scale and Reuven Bar-On's Emotional Quotient Inventory. The findings indicated that Turkish EFL…

  11. Agricultural Education Perceived Teacher Self-Efficacy: A Descriptive Study of Beginning Agricultural Education Teachers

    ERIC Educational Resources Information Center

    Wolf, Kattlyn J.

    2011-01-01

    The purpose of this study was to describe beginning agriculture teachers' perceived agricultural education teacher self-efficacy. Additionally, the researcher sought to describe the relationship among teachers' demographic characteristics and their agricultural education teacher self-efficacy. An instrument specific to agricultural education was

  12. Gender, Group Composition, Cooperation, and Self-Efficacy in Computer Studies.

    ERIC Educational Resources Information Center

    Busch, Tor

    1996-01-01

    Describes a study of Norwegian college students that investigated whether gender, group composition, or self-efficacy in computing has any impact on cooperation, giving or getting task-related help, and level of activity in student groups. Results confirms gender differences in self-efficacy in computing. (Author/LRW)

  13. A Survey Study of Chinese In-Service Teachers' Self-Efficacy about Inclusive Education

    ERIC Educational Resources Information Center

    Wang, Mian; Zan, Fei; Liu, Jiaqiu; Liu, Chunling; Sharma, Umesh

    2012-01-01

    A survey study was conducted to a total of 323 in-service teachers (110 special education teachers and 213 general education teachers) in Shanghai regarding their self-efficacy and concerns about inclusive education. Multivariate analysis results reveal that special teachers have significantly higher self-efficacy about inclusive education than

  14. Organizational Structure, Collegial Trust, and College Faculty Teaching Efficacy: A Case Study

    ERIC Educational Resources Information Center

    Okpogba, Desmond

    2011-01-01

    The purpose of this mixed-method study was to explore the relationship between faculty self-efficacy, organizational structure, and collegial trust. The concepts of teacher self-efficacy, organizational structure, and collegial trust were used to investigate any possible empirical relationships existing between these variables in a private,…

  15. A Confirmatory Study of Rating Scale Category Effectiveness for the Coaching Efficacy Scale

    ERIC Educational Resources Information Center

    Myers, Nicholas D.; Feltz, Deborah L.; Wolfe, Edward W.

    2008-01-01

    This study extended validity evidence for measures of coaching efficacy derived from the Coaching Efficacy Scale (CES) by testing the rating scale categorizations suggested in previous research. Previous research provided evidence for the effectiveness of a four-category (4-CAT) structure for high school and collegiate sports coaches; it also…

  16. A Confirmatory Study of Rating Scale Category Effectiveness for the Coaching Efficacy Scale

    ERIC Educational Resources Information Center

    Myers, Nicholas D.; Feltz, Deborah L.; Wolfe, Edward W.

    2008-01-01

    This study extended validity evidence for measures of coaching efficacy derived from the Coaching Efficacy Scale (CES) by testing the rating scale categorizations suggested in previous research. Previous research provided evidence for the effectiveness of a four-category (4-CAT) structure for high school and collegiate sports coaches; it also

  17. Electronic Cigarettes Efficacy and Safety at 12 Months: Cohort Study

    PubMed Central

    Fiore, Maria; La Vecchia, Carlo; Marzuillo, Carolina; Gualano, Maria Rosaria; Liguori, Giorgio; Cicolini, Giancarlo; Capasso, Lorenzo; D'Amario, Claudio; Boccia, Stefania; Siliquini, Roberta; Ricciardi, Walter; Villari, Paolo

    2015-01-01

    Objective To evaluate the safety and efficacy as a tool of smoking cessation of electronic cigarettes (e-cigarettes), directly comparing users of e-cigarettes only, smokers of tobacco cigarettes only, and smokers of both. Design Prospective cohort study. Final results are expected in 2019, but given the urgency of data to support policies on electronic smoking, we report the results of the 12-month follow-up. Data Sources Direct contact and structured questionnaires by phone or via internet. Methods Adults (3075 years) were included if they were smokers of ?1 tobacco cigarette/day (tobacco smokers), users of any type of e-cigarettes, inhaling ?50 puffs weekly (e-smokers), or smokers of both tobacco and e-cigarettes (dual smokers). Carbon monoxide levels were tested in a sample of those declaring tobacco smoking abstinence. Main Outcome Measures Sustained smoking abstinence from tobacco smoking at 12 months, reduction in the number of tobacco cigarettes smoked daily. Data Synthesis We used linear and logistic regression, with region as cluster unit. Results Follow-up data were available for 236 e-smokers, 491 tobacco smokers, and 232 dual smokers (overall response rate 70.8%). All e-smokers were tobacco ex-smokers. At 12 months, 61.9% of the e-smokers were still abstinent from tobacco smoking; 20.6% of the tobacco smokers and 22.0% of the dual smokers achieved tobacco abstinence. Adjusting for potential confounders, tobacco smoking abstinence or cessation remained significantly more likely among e-smokers (adjusted OR 5.19; 95% CI: 3.358.02), whereas adding e-cigarettes to tobacco smoking did not enhance the likelihood of quitting tobacco and did not reduce tobacco cigarette consumption. E-smokers showed a minimal but significantly higher increase in self-rated health than other smokers. Non significant differences were found in self-reported serious adverse events (eleven overall). Conclusions Adding e-cigarettes to tobacco smoking did not facilitate smoking cessation or reduction. If e-cigarette safety will be confirmed, however, the use of e-cigarettes alone may facilitate quitters remaining so. Registration Number NCT01785537. PMID:26061661

  18. The Cleveland Clinic-Nimbus total artificial heart. In vivo hemodynamic performance in calves and preclinical studies.

    PubMed

    McCarthy, P M; Fukamachi, K; Fukumura, F; Muramoto, K; Golding, L A; Harasaki, H

    1994-09-01

    In vitro function of the Cleveland Clinic-Nimbus electrohydraulic total artificial heart met National Heart, Lung, and Blood Institute hemodynamic guidelines for such devices. In a series of in vivo experiments, we implanted the total artificial heart in eight calves (mean weight 87 kg), one for a short-term experiment and seven for long-term experiments. The mean blood flow during support was 7.7 +/- 1.6 L/min with left atrial pressure 13 +/- 6 mm Hg, right atrial pressure 13 +/- 4 mm Hg, and aortic pressure 97 +/- 9 mm hg. Maximum pump flow (9.6 L/min) occurred after 4 days of support as a result of the high resting cardiac output of the animals. A 10% to 15% right pump stroke-volume limit effectively balanced atrial pressures, and afterload insensitivity was confirmed by the in vivo studies. Calves tolerated treadmill exercise studies well, with an average duration of 22 minutes and an average top speed of 2.1 mph. The experiments were terminated after 1 day to 120 days of support (mean 32 days). Most experiments were terminated as a result of correctable mechanical problems. In a separate study of six adult human patients undergoing orthotopic cardiac transplantation, five showed an excellent fit for the Cleveland Clinic-Nimbus total artificial heart. Further studies using chest roentgenograms, chest measurements, and transesophageal echocardiography should help predict fit of the total artificial heart in potential candidates. Initial candidates for a "vented-electric" version of the Cleveland Clinic-Nimbus total artificial heart are patients for whom univentricular (left ventricular assist device) support is not appropriate, but who require mechanical support as a bridge to cardiac transplantation. PMID:8078335

  19. Quantile Regression with a Change-point Model for Longitudinal Data: An Application to the Study of Cognitive Changes in Preclinical Alzheimers Disease

    PubMed Central

    Li, Chenxi; Dowling, N. Maritza; Chappell, Rick

    2015-01-01

    Summary Progressive and insidious cognitive decline that interferes with daily life is the defining characteristic of Alzheimers disease (AD). Epidemiological studies have found that the pathological process of AD begins years before a clinical diagnosis is made and can be highly variable within a given population. Characterizing cognitive decline in the preclinical phase of AD is critical for the development of early intervention strategies when disease-modifying therapies may be most effective. In the last decade, there has been an increased interest in the application of change-point models to longitudinal cognitive outcomes prior to and after diagnosis. Most of the proposed statistical methodology for describing decline relies upon distributional assumptions that may not hold. In this paper, we introduce a quantile regression with a change-point model for longitudinal data of cognitive function in persons bound to develop AD. A change-point in our model reflects the transition from the cognitive decline due to normal aging to the accelerated decline due to disease progression. Quantile regression avoids common distributional assumptions on cognitive outcomes and allows the covariate effects and the change-point to vary for different quantiles of the response. We provided an approach for estimating the model parameters, including the change-point, and presented inferential procedures based on the asymptotic properties of the estimators. A simulation study showed that the estimation and inferential procedures perform reasonably well in finite samples. The practical use of our model was illustrated by an application to longitudinal episodic memory outcomes from two cohort studies of aging and AD. PMID:25892034

  20. Quantile regression with a change-point model for longitudinal data: An application to the study of cognitive changes in preclinical alzheimer's disease.

    PubMed

    Li, Chenxi; Dowling, N Maritza; Chappell, Rick

    2015-09-01

    Progressive and insidious cognitive decline that interferes with daily life is the defining characteristic of Alzheimer's disease (AD). Epidemiological studies have found that the pathological process of AD begins years before a clinical diagnosis is made and can be highly variable within a given population. Characterizing cognitive decline in the preclinical phase of AD is critical for the development of early intervention strategies when disease-modifying therapies may be most effective. In the last decade, there has been an increased interest in the application of change-point models to longitudinal cognitive outcomes prior to and after diagnosis. Most of the proposed statistical methodology for describing decline relies upon distributional assumptions that may not hold. In this article, we introduce a quantile regression with a change-point model for longitudinal data of cognitive function in persons bound to develop AD. A change-point in our model reflects the transition from the cognitive decline due to normal aging to the accelerated decline due to disease progression. Quantile regression avoids common distributional assumptions on cognitive outcomes and allows the covariate effects and the change-point to vary for different quantiles of the response. We provided an approach for estimating the model parameters, including the change-point, and presented inferential procedures based on the asymptotic properties of the estimators. A simulation study showed that the estimation and inferential procedures perform reasonably well in finite samples. The practical use of our model was illustrated by an application to longitudinal episodic memory outcomes from two cohort studies of aging and AD. PMID:25892034

  1. Preclinical Study of Treatment Response in HCT-116 Cells and Xenografts with 1H-decoupled 31P MRS

    PubMed Central

    Darpolor, Moses M.; Kennealey, Peter T.; Carl Le, H; Zakian, Kristen L.; Ackerstaff, Ellen; Rizwan, Asif; Chen, Jin-Hong; Sambol, Elliot B.; Schwartz, Gary K.; Singer, Samuel; Koutcher, Jason A.

    2011-01-01

    The topoisomerase I inhibitor, irinotecan, and its active metabolite SN-38 have been shown to induce G2/M cell cycle arrest without significant cell death in human colon carcinoma cells (HCT-116). Subsequent treatment of these G2/M-arrested cells with the cyclin-dependent kinase inhibitor, flavopiridol, induced these cells to undergo apoptosis. The goal of this study was to develop a noninvasive metabolic biomarker for early tumor response and target inhibition of irinotecan followed by flavopiridol treatment in a longitudinal study. A total of eleven mice bearing HCT-116 xenografts were separated into two cohorts where one cohort was administered saline and the other treated with a sequential course of irinotecan followed by flavopiridol. Each mouse xenograft was longitudinally monitored with proton (1H)-decoupled phosphorus (31P) magnetic resonance spectroscopy (MRS) before and after treatment. A statistically significant decrease in phosphocholine (p = 0.0004) and inorganic phosphate (p = 0.0103) levels were observed in HCT-116 xenografts following treatment, which were evidenced within twenty-four hours of treatment completion. Also, a significant growth delay was found in treated xenografts. To discern the underlying mechanism for the treatment response of the xenografts, in vitro HCT-116 cell cultures were investigated with enzymatic assays, cell cycle analysis, and apoptotic assays. Flavopiridol had a direct effect on choline kinase as measured by a 67% reduction in the phosphorylation of choline to phosphocholine. Cells treated with SN-38 alone underwent 835% G2/M cell cycle arrest compared to untreated cells. In cells, flavopiridol alone induced 51% apoptosis while the sequential treatment (SN-38 then flavopiridol) resulted in 3910% apoptosis. In vivo 1H-decoupled 31P MRS indirectly measures choline kinase activity. The decrease in phosphocholine may be a potential indicator of early tumor response to the sequential treatment of irinotecan followed by flavopiridol in noninvasive and/or longitudinal studies. PMID:21994185

  2. Preclinical Evaluation of DMA, a Bisbenzimidazole, as Radioprotector: Toxicity, Pharmacokinetics, and Biodistribution Studies in Balb/c Mice.

    PubMed

    Nimesh, Hemlata; Tiwari, Vinod; Yang, Chunhua; Gundala, Sushma R; Chuttani, Krishna; Hazari, Puja P; Mishra, Anil K; Sharma, Abhisheak; Lal, Jawahar; Katyal, Anju; Aneja, Ritu; Tandon, Vibha

    2015-10-01

    Radiotherapy, a therapeutic modality of cancer treatment, nonselectively damages normal tissues as well as tumor tissues. The search is ongoing for therapeutic agents that selectively reduce radiation-induced normal tissue injury without reducing tumoricidal effect, thereby increasing the therapeutic ratio of radiation therapy. Our laboratory established 5-(4-methylpiperazin-1-yl)-2-[2'-(3,4-dimethoxyphenyl)-5'benzimidazolyl] benzimidazole (DMA) as noncytotoxic radioprotector in mammalian cells. DMA showed an excellent radioprotection in mice at single nontoxic oral dose by a dose-reduction factor of 1.28. An oxygen radical absorbing capacity assay confirmed its free-radical quenching ability. Single bolus dose and 28-days of repeated administration of DMA in mice for toxicity studies determined an LD50 of >2000 mg/kg body weight (bw) and 225 mg/kg bw, respectively, suggesting DMA is safe. Histopathology, biochemical parameters, and relative organ weight analysis revealed insignificant changes in the DMA-treated animals. The pharmacokinetic study of DMA at oral and intravenous doses showed its C(max) = 1 hour, bioavailability of 8.84%, elimination half-life of 4 hours, and an enterohepatic recirculation. Biodistribution study in mice with Ehrlich ascites tumors showed that (99m)Tc-DMA achieved its highest concentration in 1 hour and was retained up to 4 hours in the lungs, liver, kidneys, and spleen, and in a low concentration in the tumor, a solicited property of any radioprotector to protect normal cells over cancerous cells. We observed that the single-dose treatment of tumor-bearing mice with DMA 2 hours before 8 Gy total body irradiation showed an impressive rescue of radiation-induced morbidity in terms of weight loss and mortality without a change in tumor response. PMID:26240287

  3. Bioplasty for vertebral fractures: preliminary results of a pre-clinical study on goats using autologous modified skin fibroblasts

    PubMed Central

    Pola, Enrico; Nasto, Luigi A.; Tampieri, Anna; Lattanzi, W.; Di Giacomo, G.; Colangelo, D.; Ciriello, V.; Pagano, E.; Spinelli, S.; Robbins, P.D.; Logroscino, G.

    2012-01-01

    Summary The debate is still ongoing about the long term effects of the mininvasive vertebral augmentation techniques and their usefulness in treating more complex cases where a bone inducing effect more than a merely bone substitution would be suitable, such as the vertebral fractures in young patients. We previously developed a clinically relevant gene therapy approach using modified dermal fibroblasts for inducing bone healing and bone formation in different animal models. The aim of this study is to show the feasibility of a minimally invasive percutaneous intrasomatic ex vivo gene therapy approach to treat thoracolumbar vertebral fractures and anterior column bone defects in a goat model. PMID:21669153

  4. Development of Allogeneic NK Cell Adoptive Transfer Therapy in Metastatic Melanoma Patients: In Vitro Preclinical Optimization Studies

    PubMed Central

    Besser, Michal J.; Shoham, Tsipi; Harari-Steinberg, Orit; Zabari, Naama; Ortenberg, Rona; Yakirevitch, Arkadi; Nagler, Arnon; Loewenthal, Ron; Schachter, Jacob; Markel, Gal

    2013-01-01

    Natural killer (NK) cells have long been considered as potential agents for adoptive cell therapy for solid cancer patients. Until today most studies utilized autologous NK cells and yielded disappointing results. Here we analyze various modular strategies to employ allogeneic NK cells for adoptive cell transfer, including donor-recipient HLA-C mismatching, selective activation and induction of melanoma-recognizing lysis receptors, and co-administration of antibodies to elicit antibody-dependent cell cytotoxicity (ADCC). We show that NK cell activation and induction of the relevant lysis receptors, as well as co-administration of antibodies yield substantial anti-cancer effects, which are functionally superior to HLA-C mismatching. Combination of the various strategies yielded improved effects. In addition, we developed various clinically-compatible ex vivo expansion protocols that were optimized according to fold expansion, purity and expression of lysis receptors. The main advantages of employing allogeneic NK cells are accessibility, the ability to use a single donor for many patients, combination with various strategies associated with the mechanism of action, e.g. antibodies and specific activation, as well as donor selection according to HLA or CD16 genotypes. This study rationalizes a clinical trial that combines adoptive transfer of highly potent allogeneic NK cells and antibody therapy. PMID:23483943

  5. A Novel Pre-Clinical Murine Model to Study the Life Cycle and Progression of Cervical and Anal Papillomavirus Infections

    PubMed Central

    Cladel, Nancy M.; Budgeon, Lynn R.; Balogh, Karla K.; Cooper, Timothy K.; Hu, Jiafen; Christensen, Neil D.

    2015-01-01

    Background Papillomavirus disease and associated cancers remain a significant health burden in much of the world. The current protective vaccines, Gardasil and Cervarix, are expensive and not readily available to the underprivileged. In addition, the vaccines have not gained wide acceptance in the United States nor do they provide therapeutic value. Papillomaviruses are strictly species specific and thus human viruses cannot be studied in an animal host. An appropriate model for mucosal disease has long been sought. We chose to investigate whether the newly discovered mouse papillomavirus, MmuPV1, could infect mucosal tissues in Foxn1nu/Foxn1nu mice. Methods The vaginal and anal canals of Foxn1nu/Foxn1nu mice were gently abraded using Nonoxynol-9 and Doctors BrushPicks and MmuPV1 was delivered into the vaginal tract or the anal canal. Results Productive vaginal, cervical and anal infections developed in all mice. Vaginal/cervical infections could be monitored by vaginal lavage. Dysplasias were evident in all animals. Conclusions Anogenital tissues of a common laboratory mouse can be infected with a papillomavirus unique to that animal. This observation will pave the way for fundamental virological and immunological studies that have been challenging to carry out heretofore due to lack of a suitable model system. PMID:25803616

  6. Time Course for Onset and Recovery from Effects of a Novel Male Reproductive Toxicant: Implications for Apical Preclinical Study Designs.

    PubMed

    Powles-Glover, Nicola; Mitchard, Terri; Stewart, Jane

    2015-06-01

    In the pharmaceutic ICH S5(R2) guidelines for reproductive toxicity testing, a premating dose duration of 14 days is considered sufficient for assessment of male fertility for compounds that are not testicular toxicants. A novel ?7 subtype of nicotinic acetylcholine receptor (?7nAChR) agonist, originally intended for treatment of Alzheimer's disease, did not cause changes in sperm counts, motility, or testicular histopathology in rat toxicity studies of up to 6 months duration. However, profound decrements in male fertility (reduced pregnancy rates and litter sizes) occurred after 11 weeks of dosing in male rats. In two time-course investigations, dosed male rats were paired with undosed females after 5, 14, and 28 daily doses and again after 2 and 4 weeks off-dose. Effects on male fertility were undetectable after 5 days. After 14 days, there was no effect on pregnancy rate, but preimplantation losses were increased. Effects on both pregnancy rates and preimplantation losses were clearly detectable after 28 days, but were of lesser magnitude than after 11 weeks of dosing. Fertility recovered rapidly after dose cessation. These studies illustrate the sensitivity of a long premating dose period at revealing hazard and determining the magnitude of effect on male fertility for compounds that are intended for chronic administration and do not affect testicular histopathology. PMID:26194980

  7. Image-guided drug delivery: preclinical applications and clinical translation.

    PubMed

    Ojha, Tarun; Rizzo, Larissa; Storm, Gert; Kiessling, Fabian; Lammers, Twan

    2015-08-01

    Image-guided drug delivery refers to the combination of drug targeting and imaging. Preclinically, image-guided drug delivery can be used for several different purposes, including for monitoring biodistribution, target site accumulation, off-target localization, drug release and drug efficacy. Clinically, it holds significant potential for preselecting patients. In this editorial, we briefly summarize the main principles of image-guided drug delivery, and we describe its potential for facilitating, furthering and personalizing nanomedicine treatments. PMID:26083469

  8. 177Lu-EC0800 combined with the antifolate pemetrexed: preclinical pilot study of folate receptor targeted radionuclide tumor therapy.

    PubMed

    Reber, Josefine; Haller, Stephanie; Leamon, Christopher P; Mller, Cristina

    2013-11-01

    Targeted radionuclide therapy has shown impressive results for the palliative treatment of several types of cancer diseases. The folate receptor has been identified as specifically associated with a variety of frequent tumor types. Therefore, it is an attractive target for the development of new radionuclide therapies using folate-based radioconjugates. Previously, we found that pemetrexed (PMX) has a favorable effect in reducing undesired renal uptake of radiofolates. Moreover, PMX also acts as a chemotherapeutic and radiosensitizing agent on tumors. Thus, the aim of our study was to investigate the combined application of PMX and the therapeutic radiofolate (177)Lu-EC0800. Determination of the combination index (CI) revealed a synergistic inhibitory effect of (177)Lu-EC0800 and PMX on the viability of folate receptor-positive cervical (KB) and ovarian (IGROV-1) cancer cells in vitro (CI < 0.8). In an in vivo study, tumor-bearing mice were treated with (177)Lu-EC0800 (20 MBq) and a subtherapeutic (0.4 mg) or therapeutic amount (1.6 mg) of PMX. Application of (177)Lu-EC0800 with PMXther resulted in a two- to four-fold enhanced tumor growth delay and a prolonged survival of KB and IGROV-1 tumor-bearing mice, as compared to the combination with PMXsubther or untreated control mice. PMXsubther protected the kidneys from undesired side effects of (177)Lu-EC0800 (20 MBq) by reducing the absorbed radiation dose. Intact kidney function was shown by determination of plasma parameters and quantitative single-photon emission computed tomography using (99m)Tc-DMSA. Our results confirmed the anticipated dual role of PMX. Its unique features resulted in an improved antitumor effect of folate-based radionuclide therapy and prevented undesired radio-nephrotoxicity. PMID:24030631

  9. Fluorine-18-fluorodeoxygglucose-guided breast cancer surgery with a positron-sensitive probe: Validation in preclinical studies

    SciTech Connect

    Raylman, R.R.; Fisher, S.J.; Brown, R.S.; Ethier, S.P.; Wahl, R.L.

    1995-10-01

    In this study, the feasibility of utilizing 2-deoxy-2-fluoro-d-glucose (FDG) in conjunction with a positron-sensitive intraoperative probe to guide breast tumor excision was investigated. The probe was constructed with a plastic scintillator tip coupled to a photomultiplier tube with fiber optic cable. Anticipated resolution degradation was evaluated by measurement of line spread functions in the presence of background radiation. Realistic photon background distributions were simulated with a human torso phantom and a cardiac insert. The relationship between resolution and energy threshold was measured to find the optimal discriminator settings. In addition, probe sensitivity as a function of energy threshold was determined for various size-simulated tumors. Finally, the ability to localize breast cancers in vivo was tested in a rodent model. Mammary rat tumors implanted in Lewis rats were examined after injection with FDG; these results were correlated with those of histologic analyses. Measurements of line spread functions indicated that resolution could be maximized in a realistic background photon environment by increasing the energy threshold to levels at or above the Compton continuum edge (340 keV). At this setting, the probe`s sensitivity was determined to be 58 and 11 cps/{mu}Ci for 3.18- and 6.35-mm diameter simulated tumors, respectively. Probe readings correlated well with histologic results; the probe was generally able to discriminate between tumor and normal tissue. This study indicates that breast cancer surgery guided by a positron-sensitive probe warrants future evaluation in breast-conserving surgery of patients with breast cancer. 23 refs., 5 figs.

  10. A comparative study of students' performance in preclinical physiology assessed by multiple choice and short essay questions.

    PubMed

    Oyebola, D D; Adewoye, O E; Iyaniwura, J O; Alada, A R; Fasanmade, A A; Raji, Y

    2000-01-01

    This study was designed to compare the performance of medical students in physiology when assessed by multiple choice questions (MCQs) and short essay questions (SEQs). The study also examined the influence of factors such as age, sex, O/level grades and JAMB scores on performance in the MCQs and SEQs. A structured questionnaire was administered to 264 medical students' four months before the Part I MBBS examination. Apart from personal data of each student, the questionnaire sought information on the JAMB scores and GCE O' Level grades of each student in English Language, Biology, Chemistry, Physics and Mathematics. The physiology syllabus was divided into five parts and the students were administered separate examinations (tests) on each part. Each test consisted of MCQs and SEQs. The performance in MCQs and SEQs were compared. Also, the effects of JAMB scores and GCE O/level grades on the performance in both the MCQs and SEQs were assessed. The results showed that the students performed better in all MCQ tests than in the SEQs. JAMB scores and O' level English Language grade had no significant effect on students' performance in MCQs and SEQs. However O' level grades in Biology, Chemistry, Physics and Mathematics had significant effects on performance in MCQs and SEQs. Inadequate knowledge of physiology and inability to present information in a logical sequence are believed to be major factors contributing to the poorer performance in the SEQs compared with MCQs. In view of the finding of significant association between performance in MCQs and SEQs and GCE O/level grades in science subjects and mathematics, it was recommended that both JAMB results and the GCE results in the four O/level subjects above may be considered when selecting candidates for admission into the medical schools. PMID:11713989

  11. Universal wet-milling technique to prepare oral nanosuspension focused on discovery and preclinical animal studies - Development of particle design method.

    PubMed

    Niwa, Toshiyuki; Miura, Satoru; Danjo, Kazumi

    2011-02-28

    Simple and easy methods to prepare oral nanosuspension of a poorly water-soluble pharmaceutical candidate compound, called a candidate, have been developed to support the discovery and preclinical studies using animals. The different wet-milling processes in miniature, middle and large preparation scales have been established in order to cover the various types of studies with wide scale. The powder of phenytoin, a poorly water-soluble model drug candidate, was suspended in the aqueous medium, in which the appropriate dispersing agents were dissolved, and milled by agitating together with small hard beads made of zirconia. Three general-purpose equipments with stirring, oscillating and turbulent motions were applied instead of the specific milling machine with high power to avoid much investment at such early development stage. The operational condition and dispersing agents were optimized to obtain finer particles using the middle-scaled oscillating beads-milling apparatus in particular. It was found that the nanosuspension, which whole particle distribution was in the submicron range, was successfully produced within the running time around 10min. By applying the newly developed dispersing medium, the nanoparticles with identical size distribution were also prepared using the stirring and turbulent methods on miniature and large scales, respectively; indicating only 50mg to 30g or more amount of candidate could be milled to nanosuspension using three equipments. The crystalline analysis indicated that the both crystal form and crystallinity of the original bulk drug completely remained after wet-milling process. The results demonstrated that the wet-milling methods developed in this research would be a fundamental technique to produce nanosuspension for poorly water-soluble and oral absorbable drug candidates. PMID:21167922

  12. Lost in translation: preclinical studies on 3,4-methylenedioxymethamphetamine provide information on mechanisms of action, but do not allow accurate prediction of adverse events in humans.

    PubMed

    Green, A R; King, M V; Shortall, S E; Fone, K C F

    2012-07-01

    3,4-Methylenedioxymethamphetamine (MDMA) induces both acute adverse effects and long-term neurotoxic loss of brain 5-HT neurones in laboratory animals. However, when choosing doses, most preclinical studies have paid little attention to the pharmacokinetics of the drug in humans or animals. The recreational use of MDMA and current clinical investigations of the drug for therapeutic purposes demand better translational pharmacology to allow accurate risk assessment of its ability to induce adverse events. Recent pharmacokinetic studies on MDMA in animals and humans are reviewed and indicate that the risks following MDMA ingestion should be re-evaluated. Acute behavioural and body temperature changes result from rapid MDMA-induced monoamine release, whereas long-term neurotoxicity is primarily caused by metabolites of the drug. Therefore acute physiological changes in humans are fairly accurately mimicked in animals by appropriate dosing, although allometric dosing calculations have little value. Long-term changes require MDMA to be metabolized in a similar manner in experimental animals and humans. However, the rate of metabolism of MDMA and its major metabolites is slower in humans than rats or monkeys, potentially allowing endogenous neuroprotective mechanisms to function in a species specific manner. Furthermore acute hyperthermia in humans probably limits the chance of recreational users ingesting sufficient MDMA to produce neurotoxicity, unlike in the rat. MDMA also inhibits the major enzyme responsible for its metabolism in humans thereby also assisting in preventing neurotoxicity. These observations question whether MDMA alone produces long-term 5-HT neurotoxicity in human brain, although when taken in combination with other recreational drugs it may induce neurotoxicity. PMID:22188379

  13. Preclinical potency and safety studies of an AAV2-mediated gene therapy vector for the treatment of MERTK associated retinitis pigmentosa.

    PubMed

    Conlon, Thomas J; Deng, Wen-Tao; Erger, Kirsten; Cossette, Travis; Pang, Ji-jing; Ryals, Renee; Clment, Nathalie; Cleaver, Brian; McDoom, Issam; Boye, Shannon E; Peden, Marc C; Sherwood, Mark B; Abernathy, Corinne R; Alkuraya, Fowzan S; Boye, Sanford L; Hauswirth, William W

    2013-03-01

    Abstract Proof of concept for MERTK gene replacement therapy has been demonstrated using different viral vectors in the Royal College of Surgeon (RCS) rat, a well characterized model of recessive retinitis pigmentosa that contains a mutation in the Mertk gene. MERTK plays a key role in renewal of photoreceptor outer segments (OS) by phagocytosis of shed OS tips. Mutations in MERTK cause impaired phagocytic activity and accumulation of OS debris in the interphotoreceptor space that ultimately leads to photoreceptor cell death. In the present study, we conducted a series of preclinical potency and GLP-compliant safety evaluations of an adeno-associated virus type 2 (AAV2) vector expressing human MERTK cDNA driven by the retinal pigment epithelium-specific, VMD2 promoter. We demonstrate the potency of the vector in RCS rats by improved electroretinogram (ERG) responses in treated eyes compared with contralateral untreated controls. Toxicology and biodistribution studies were performed in Sprague-Dawley (SD) rats injected with two different doses of AAV vectors and buffer control. Delivery of vector in SD rats did not result in a change in ERG amplitudes of rod and cone responses relative to balanced salt solution control-injected eyes, indicating that administration of AAV vector did not adversely affect normal retinal function. In vivo fundoscopic analysis and postmortem retinal morphology of the vector-injected eyes were normal compared with controls. Evaluation of blood smears showed the lack of transformed cells in the treated eyes. All injected eyes and day 1 blood samples were positive for vector genomes, and all peripheral tissues were negative. Our results demonstrate the potency and safety of the AAV2-VMD2-hMERTK vector in animal models tested. A GMP vector has been manufactured and is presently in clinical trial. PMID:23692380

  14. Safety data on 19 vehicles for use in 1 month oral rodent pre-clinical studies: administration of hydroxypropyl-ß-cyclodextrin causes renal toxicity.

    PubMed

    Healing, Guy; Sulemann, Tabassum; Cotton, Peter; Harris, Jayne; Hargreaves, Adam; Finney, Rowena; Kirk, Sarah; Schramm, Carolin; Garner, Clare; Pivette, Perrine; Burdett, Lisa

    2016-01-01

    Potential new drugs are assessed in pre-clinical in vivo studies to determine their safety profiles. The drugs are formulated in vehicles suitable for the route of administration and the physicochemical properties of the drug, aiming to achieve optimal exposure in the test species. The availability of safety data on vehicles is often limited (incomplete data, access restricted/private databases). Nineteen potentially useful vehicles that contained new and/or increased concentrations of excipients and for which little safety data have been published were tested. Vehicles were dosed orally once daily to HanWistar rats for a minimum of 28 days and a wide range of toxicological parameters were assessed. Only 30% (w/v) hydroxypropyl-ß-cyclodextrin was found unsuitable owing to effects on liver enzymes (AST, ALT and GLDH), urinary volume and the kidneys (tubular vacuolation and tubular pigment). 20% (v/v) oleic acid caused increased salivation and hence this vehicle should be used with caution. As 40% (v/v) tetraethylene glycol affected urinary parameters, its use should be carefully considered, particularly for compounds suspected to impact the renal system and studies longer than 1 month. There were no toxicologically significant findings with 10% (v/v) dimethyl sulphoxide, 20% (v/v) propylene glycol, 33% (v/v) Miglyol®812, 20% (w/v) Kolliphor®RH40, 10% (w/v) Poloxamer 407, 5% (w/v) polyvinylpyrrolidone K30 or 10% (v/v) Labrafil®M1944. All other vehicles tested caused isolated or low magnitude effects which would not prevent their use. The aim of sharing these data, including adverse findings, is to provide meaningful information for vehicle selection, thereby avoiding repetition of animal experimentation. PMID:25959454

  15. Resilience to the effects of social stress: Evidence from clinical and preclinical studies on the role of coping strategies

    PubMed Central

    Wood, Susan K.; Bhatnagar, Seema

    2014-01-01

    The most common form of stress encountered by people stems from one's social environment and is perceived as more intense than other types of stressors. One feature that may be related to differential resilience or vulnerability to stress is the type of strategy used to cope with the stressor, either active or passive coping. This review focuses on models of social stress in which individual differences in coping strategies produce resilience or vulnerability to the effects of stress. Neurobiological mechanisms underlying these individual differences are discussed. Overall, the literature suggests that there are multiple neural mechanisms that underlie individual differences in stress-induced resilience and vulnerability. How these mechanisms interact with one another to produce a resilient or vulnerable phenotype is not understood and such mechanisms have been poorly studied in females and in early developmental periods. Finally, we propose that resilience may be stress context specific and resilience phenotypes may need to be fine-tuned to suit a shifting environment. PMID:25580450

  16. Inhibitory Effects of Platelet-Rich Plasma on Intervertebral Disc Degeneration: A Preclinical Study in a Rabbit Model

    PubMed Central

    Gui, Keke; Ren, Weimin; Yu, Yonglin; Li, Xin; Dong, Jiachun; Yin, Wangping

    2015-01-01

    Background Platelet-rich plasma (PRP) contains multiple growth hormones that may stimulate tissue repair. This study aimed to assess the effects of PRP in a rabbit model of IDD (annulus fibrosus puncture). Material/Methods Thirty-six adult New Zealand white rabbits were randomly divided into 3 groups: 0.1 mL PRP (group A), 0.1 mL phosphate-buffered saline (group B), and control (group C) (n=12/group). Annulus fibrosus puncture was performed to establish L4/5 and L5/6 IDD models. Two and 4 weeks later, 6 rabbits from each group were given an IVD injection at L4/5 and L5/6. Two or 4 weeks after injection, rabbits were scanned with X-ray and MRI before being sacrificed. IVDs were collected for hematoxylin and eosin, Massons trichrome, and Safranin O staining, and type II collagen immunohistochemistry. Results Over time, IVD height and disc imaging signal intensity decreased gradually in groups B and C, but only slightly in group A (baseline: 100% for all groups; A: 95.94.2% at 4 weeks, 90.18.4 at 6 weeks; B: 75.35.7% at 4 weeks, 70.86.4% at 6 weeks; C: 74.75.5% at 4 weeks, 69.96.2% at 6 weeks; all P<0.001, P<0.01 between A vs. B and C). Degenerative histological changes in IVDs in groups B and C were more severe compared with group A. Conclusions Platelet-rich plasma interventions can effectively attenuate the IDD process in rabbits. PMID:25965093

  17. A Preclinical Murine Model of Hepatic Metastases

    PubMed Central

    Soares, Kevin C.; Foley, Kelly; Olino, Kelly; Leubner, Ashley; Mayo, Skye C.; Jain, Ajay; Jaffee, Elizabeth; Schulick, Richard D.; Yoshimura, Kiyoshi; Edil, Barish; Zheng, Lei

    2014-01-01

    Numerous murine models have been developed to study human cancers and advance the understanding of cancer treatment and development. Here, a preclinical, murine pancreatic tumor model of hepatic metastases via a hemispleen injection of syngeneic murine pancreatic tumor cells is described. This model mimics many of the clinical conditions in patients with metastatic disease to the liver. Mice consistently develop metastases in the liver allowing for investigation of the metastatic process, experimental therapy testing, and tumor immunology research. PMID:25285458

  18. SU-E-J-156: Preclinical Inverstigation of Dynamic Tumor Tracking Using Vero SBRT Linear Accelerator: Motion Phantom Dosimetry Study

    SciTech Connect

    Mamalui-Hunter, M; Wu, J; Li, Z; Su, Z

    2014-06-01

    Purpose: Following the ‘end-to-end testing’ paradigm of Dynamic Target Tracking option in our Image-Guided dedicated SBRT VeroTM linac, we verify the capability of the system to deliver planned dose to moving targets in the heterogeneous thorax phantom (CIRSTM). The system includes gimbaled C-band linac head, robotic 6 degree of freedom couch and a tumor tracking method based on predictive modeling of target position using fluoroscopically tracked implanted markers and optically tracked infrared reflecting external markers. Methods: 4DCT scan of the motion phantom with the VisicoilTM implanted marker in the close vicinity of the target was acquired, the ‘exhale’=most prevalent phase was used for planning (iPlan by BrainLabTM). Typical 3D conformal SBRT treatment plans aimed to deliver 6-8Gy/fx to two types of targets: a)solid water-equivalent target 3cm in diameter; b)single VisicoilTM marker inserted within lung equivalent material. The planning GTV/CTV-to-PTV margins were 2mm, the block margins were 3 mm. The dose calculated by MonteCarlo algorithm with 1% variance using option Dose-to-water was compared to the ion chamber (CC01 by IBA Dosimetry) measurements in case (a) and GafchromicTM EBT3 film measurements in case (b). During delivery, the target 6 motion patterns available as a standard on CIRSTM motion phantom were investigated: in case (a), the target was moving along the designated sine or cosine4 3D trajectory; in case (b), the inserted marker was moving sinusoidally in 1D. Results: The ion chamber measurements have shown the agreement with the planned dose within 1% under all the studied motion conditions. The film measurements show 98.1% agreement with the planar calculated dose (gamma criteria: 3%/3mm). Conclusion: We successfully verified the capability of the SBRT VeroTM linac to perform real-time tumor tracking and accurate dose delivery to the target, based on predictive modeling of the correlation between implanted marker motion and external surrogate of breathing motion.

  19. A Novel Inherently Radiopaque Bead for Transarterial Embolization to Treat Liver Cancer - A Pre-clinical Study

    PubMed Central

    Duran, Rafael; Sharma, Karun; Dreher, Matthew R.; Ashrafi, Koorosh; Mirpour, Sahar; Lin, MingDe; Schernthaner, Ruediger E.; Schlachter, Todd R.; Tacher, Vania; Lewis, Andrew L.; Willis, Sean; den Hartog, Mark; Radaelli, Alessandro; Negussie, Ayele H.; Wood, Bradford J.; Geschwind, Jean-François H.

    2016-01-01

    Purpose: Embolotherapy using microshperes is currently performed with soluble contrast to aid in visualization. However, administered payload visibility dimishes soon after delivery due to soluble contrast washout, leaving the radiolucent bead's location unknown. The objective of our study was to characterize inherently radiopaque beads (RO Beads) in terms of physicomechanical properties, deliverability and imaging visibility in a rabbit VX2 liver tumor model. Materials and Methods: RO Beads, which are based on LC Bead® platform, were compared to LC Bead. Bead size (light microscopy), equilibrium water content (EWC), density, X-ray attenuation and iodine distribution (micro-CT), suspension (settling times), deliverability and in vitro penetration were investigated. Fifteen rabbits were embolized with either LC Bead or RO Beads + soluble contrast (iodixanol-320), or RO Beads+dextrose. Appearance was evaluated with fluoroscopy, X-ray single shot, cone-beam CT (CBCT). Results: Both bead types had a similar size distribution. RO Beads had lower EWC (60-72%) and higher density (1.21-1.36 g/cc) with a homogeneous iodine distribution within the bead's interior. RO Beads suspension time was shorter than LC Bead, with durable suspension (>5 min) in 100% iodixanol. RO Beads ≤300 µm were deliverable through a 2.3-Fr microcatheter. Both bead types showed similar penetration. Soluble contrast could identify target and non-target embolization on fluoroscopy during administration. However, the imaging appearance vanished quickly for LC Bead as contrast washed-out. RO Beads+contrast significantly increased visibility on X-ray single shot compared to LC Bead+contrast in target and non-target arteries (P=0.0043). Similarly, RO beads demonstrated better visibility on CBCT in target arteries (P=0.0238) with a trend in non-target arteries (P=0.0519). RO Beads+dextrose were not sufficiently visible to monitor embolization using fluoroscopy. Conclusion: RO Beads provide better conspicuity to determine target and non-target embolization compared to LC Bead which may improve intra-procedural monitoring and post-procedural evaluation of transarterial embolization. PMID:26722371

  20. The prevalence and consequences of burnout on a group of preclinical dental students

    PubMed Central

    Atalayin, Cigdem; Balkis, Murat; Tezel, Huseyin; Onal, Banu; Kayrak, Gul

    2015-01-01

    Objective: The aim of this study is to investigate the prevalence of burnout among a group of Turkish preclinical dental students, to compare the level of burnout and to determine the consequences in structural equation model. Materials and Methods: Preclinical dental students (n = 329, 50.5% of females and 49.5% of males) aged between 18 and 24 took part in the study. Maslach burnout inventory student version, academic satisfaction scale, and personal information sheet were used to gather data. Pearson correlation analyses, t-test, and one-way ANOVA were used for statistical analysis. The proposed theoretical model was tested via observed variable path analysis using maximum likelihood parameter estimation with AMOS 7.0. Results: About 22.3% of students had high level of emotional exhaustion, 16.7% of students had high level of cynicism, and 17.9% of students suffered from high level of reduced academic efficacy. While the students attending the first grade reported higher level of reduced academic efficacy, the students in the third grade reported higher level of emotional exhaustion. Academic workload played an important role in the development of burnout. As consequences of burnout, students with high levels of burnout intended to change their current major and did not to plan to continue to postgraduate education. Students with high level of burnout reported less level of academic satisfaction and academic achievement. Conclusions: Creating awareness on the burnout of dental students from the preclinical period may be useful for prevention and more compatible dental education environment. PMID:26430363

  1. Methodological Standardization for the Preclinical Evaluation of Renal Sympathetic Denervation

    PubMed Central

    Sakakura, Kenichi; Ladich, Elena; Edelman, Elazer R.; Markham, Peter; Stanley, James R.L.; Keating, John; Kolodgie, Frank D.; Virmani, Renu; Joner, Michael

    2015-01-01

    Transcatheter ablation of renal autonomic nerves is a viable option for the treatment of resistent arterial hypertension; however, structured preclinical evaluation with standardization of analytical procedures remains a clear gap in this field. Here we discuss the topics relevant to the preclinical model for the evaluation of renal denervation (RDN) devices and report methodologies and criteria towards standardization of the safety and efficacy assessment, including histopathological evaluations of the renal artery, peri-arterial nerves, and associated peri-adventitial tissues. The preclinical swine renal artery model can be used effectively to assess both the safety and efficacy of RDN technologies. Assessment of the efficacy of RDN modalities primarily focuses on the determination of the depth of penetration of treatment-related injury (eg, necrosis) of the peri-arterial tissues and its relationship (ie, location and distance) and affect on the associated renal nerves and the correlation thereof with proxy biomarkers including renal norepinephrine concentrations and nerve-specific immunohistochemical stains (eg, tyrosine hydroxylase). The safety evaluation of RDN technologies involves assessing for adverse effects on tissues local to the site of treatment (ie, on the arterial wall) as well as tissues at a distance (eg, soft tissue, veins, arterial branches, skeletal muscle, adrenal gland, ureters). Increasing experience will help to create a standardized means of examining all arterial beds subject to ablative energy and in doing so enable us to proceed to optimize development and assessment of these emerging technologies. PMID:25240550

  2. Preclinical Study of Novel Gene Silencer Pyrrole-Imidazole Polyamide Targeting Human TGF-β1 Promoter for Hypertrophic Scars in a Common Marmoset Primate Model

    PubMed Central

    Igarashi, Jun; Fukuda, Noboru; Inoue, Takashi; Nakai, Shigeki; Saito, Kosuke; Fujiwara, Kyoko; Matsuda, Hiroyuki; Ueno, Takahiro; Matsumoto, Yoshiaki; Watanabe, Takayoshi; Nagase, Hiroki; Bando, Toshikazu; Sugiyama, Hiroshi; Itoh, Toshio; Soma, Masayoshi

    2015-01-01

    We report a preclinical study of a pyrrole-imidazole (PI) polyamide that targets the human transforming growth factor (hTGF)-β1 gene as a novel transcriptional gene silencer in a common marmoset primate model. We designed and then synthesized PI polyamides to target the hTGF-β1 promoter. We examined effects of seven PI polyamides (GB1101-1107) on the expression of hTGF-β1 mRNA stimulated with phorbol 12-myristate 13-acetate (PMA) in human vascular smooth muscle cells. GB1101, GB1105 and GB1106 significantly inhibited hTGF-β1 mRNA expression. We examined GB1101 as a PI polyamide to hTGF-β1 for hypertrophic scars in marmosets in vivo. Injection of GB1101 completely inhibited hypertrophic scar formation at 35 days post-incision and inhibited cellular infiltration, TGF-β1 and vimentin staining, and epidermal thickness. Mismatch polyamide did not affect hypertrophic scarring or histological changes. Epidermis was significantly thinner with GB1101 than with water and mismatch PI polyamides. We developed the PI polyamides for practical ointment medicines for the treatment of hypertrophic scars. FITC-labeled GB1101 with solbase most efficiently distributed in the nuclei of epidermal keratinocytes, completely suppressed hypertropic scarring at 42 days after incision, and considerably inhibited epidermal thickness and vimentin-positive fibroblasts. PI polyamides targeting hTGF-β1 promoter with solbase ointment will be practical medicines for treating hypertrophic scars after surgical operations and skin burns. PMID:25938472

  3. Validated LC-MS/MS assay for the determination of felbinac: Application to a preclinical pharmacokinetics study of felbinac trometamol injection in rat.

    PubMed

    Zhang, Chao; Wang, Lu; Yang, Wei; Wang, Xisha; Fawcett, J Paul; Sun, Yantong; Gu, Jingkai

    2009-08-15

    A rapid and sensitive analytical method based on high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the determination of felbinac in rat plasma, bile, urine, feces and tissue. Sample preparation involved liquid-liquid extraction with ethyl ether-dichloromethane (60:40, v/v). Chromatography of felbinac and the internal standard probenecid was performed within 2min on a Venusil MP C(18) column (100mmx4.6mm i.d., 5microm) with a mobile phase consisting of acetonitrile-5mM ammonium acetate containing 0.1% formic acid (pH 3.0) (80:20, v/v) at a flow rate of 1.2ml/min. Detection by electrospray negative ionization mass spectrometry and multiple-reaction monitoring of the transitions of felbinac at m/z 211.1-->167.0 and of probenecid at m/z 283.9-->239.9 was linear over the concentration range 5-5000ng/ml with a lower limit of quantitation of 5ng/ml using a sample volume of only 50microl. Intra- and inter-day precisions (as relative standard deviation, R.S.D.) were < or =7.3% and < or =6.4%, respectively, and accuracy (as relative error, R.E.) was in the range -2.1 to 7.4%. Recoveries and matrix effects were satisfactory in all the biological matrices examined. The method was applied to a preclinical pharmacokinetic study in rat involving a single intravenous injection of felbinac trometamol. PMID:19376665

  4. Science teaching self-efficacy in a primary school: A case study

    NASA Astrophysics Data System (ADS)

    de Laat, Jenny; Watters, James J.

    1995-12-01

    Bandura's theory of self-efficacy predicts that teachers with high, self-efficacy should persist longer, provide a greater academic focus in child-centred classrooms and exhibit different types of feedback than teachers who have lower self-efficacy. This paper reports on the science teaching self-efficacy in a group of teachers at a state primary school. The research was conducted in two stages using firstly the Science Teaching Efficacy Beliefs Instrument (STEBI-A) to identify cases, and secondly, a semistructured interview coupled with classroom observations. Thirty seven teaching staff were surveyed with the STEBI-A instrument. The five highest and five lowest scoring teachers on the personal science teaching self-efficacy subscale of the STEBI-A were interviewed. The analysis of interviews and observations indicated that teachers with high personal science teaching self-efficacy have had a long interest in science and a relatively strong background of formal science studies with opportunities for exploring out of school activities. Although they may have experienced negative science experiences in their own schooling other ameliorating factors existed which maintained their interest. Their instructional strategies in science lessons were more child-centred than those reported by teachers with lower personal science teaching self-efficacy. The implications of the results for the inservice training of teachers are discussed.

  5. Preclinical assessment of infant formula.

    PubMed

    Lönnerdal, Bo

    2012-01-01

    Infant formulas are the sole or predominant source of nutrition for many infants and are fed during a sensitive period of development and may therefore have short- and long-term consequences for infant health. Preclinical safety assessment therefore needs to include both short-term and long-term studies in animals. It is recommended that procedures are instituted by which experts may serve as independent scientists for companies developing novel products, without having their integrity compromised, and later serve the legislative institutions. A two-level assessment approach to determine the potential toxicity of a novel ingredient, its metabolites, and their effects in the matrix on developing organ systems has been suggested by IOM. This appears reasonable, as novel ingredients can be of different levels of concern. The use of modern methods in genomics and proteomics should be considered in these evaluation processes as well as novel methods to evaluate outcomes, including metabolomics and molecular techniques to assess the microbiome. PMID:22699767

  6. Validation of a Preclinical Spinal Safety Model: Effects of Intrathecal Morphine in the Neonatal Rat

    PubMed Central

    Westin, B. David; Walker, Suellen M.; Deumens, Ronald; Grafe, Marjorie; Yaksh, Tony L.

    2010-01-01

    Background Preclinical studies demonstrate increased neuroapoptosis after general anesthesia in early life. Neuraxial techniques may minimize potential risks, but there has been no systematic evaluation of spinal analgesic safety in developmental models. We aimed to validate a preclinical model for evaluating dose-dependent efficacy, spinal cord toxicity, and long term function following intrathecal morphine in the neonatal rat. Methods Lumbar intrathecal injections were performed in anesthetized rats aged postnatal day (P)3, 10 and 21. The relationship between injectate volume and segmental spread was assessed post mortem and by in-vivo imaging. To determine the antinociceptive dose, mechanical withdrawal thresholds were measured at baseline and 30 minutes following intrathecal morphine. To evaluate toxicity, doses up to the maximum tolerated were administered, and spinal cord histopathology, apoptosis and glial response were evaluated 1 and 7 days following P3 or P21 injection. Sensory thresholds and gait analysis were evaluated at P35. Results Intrathecal injection can be reliably performed at all postnatal ages and injectate volume influences segmental spread. Intrathecal morphine produced spinally-mediated analgesia at all ages with lower dose requirements in younger pups. High dose intrathecal morphine did not produce signs of spinal cord toxicity or alter long-term function. Conclusions The therapeutic ratio for intrathecal morphine (toxic dose / antinociceptive dose) was at least 300 at P3, and at least 20 at P21 (latter doses limited by side effects). This data provides relative efficacy and safety data for comparison with other analgesic preparations and contributes supporting evidence for the validity of this preclinical neonatal safety model. PMID:20526189

  7. The Exploration of Elementary School Teachers' Internet Self-Efficacy and Information Commitments: A Study in Taiwan

    ERIC Educational Resources Information Center

    Wu, Ying-Tien; Wang, Li-Jen

    2015-01-01

    This study aimed to explore teachers' Internet self-efficacy and information commitments. More importantly, this study also attempted to identify possible factors that affect the teachers' Internet self-efficacy. The participants were 301 elementary school teachers. In this study, the Internet Self-efficacy Survey (ISS) and the Information

  8. The Exploration of Elementary School Teachers' Internet Self-Efficacy and Information Commitments: A Study in Taiwan

    ERIC Educational Resources Information Center

    Wu, Ying-Tien; Wang, Li-Jen

    2015-01-01

    This study aimed to explore teachers' Internet self-efficacy and information commitments. More importantly, this study also attempted to identify possible factors that affect the teachers' Internet self-efficacy. The participants were 301 elementary school teachers. In this study, the Internet Self-efficacy Survey (ISS) and the Information…

  9. Preclinical evaluation of 89Zr-labeled anti-CD44 monoclonal antibody RG7356 in mice and cynomolgus monkeys: Prelude to Phase 1 clinical studies.

    PubMed

    Vugts, Danielle J; Heuveling, Derrek A; Stigter-van Walsum, Marijke; Weigand, Stefan; Bergstrom, Mats; van Dongen, Guus A M S; Nayak, Tapan K

    2014-01-01

    RG7356 is a humanized antibody targeting the constant region of CD44. RG7356 was radiolabeled with (89)Zr for preclinical evaluations in tumor xenograft-bearing mice and normal cynomolgus monkeys to enable study of its biodistribution and the role of CD44 expression on RG7356 uptake. Studies with (89)Zr-RG7356 were performed in mice bearing tumor xenografts that differ in the level of CD44 expression (CD44(+) or CD44(-)) and RG7356 responsiveness (resp or non-resp): MDA-MB-231 (CD44(+), resp), PL45 (CD44(+), non-resp) and HepG2 (CD44(-), non-resp). Immuno-PET whole body biodistribution studies were performed in normal cynomolgus monkeys to determine normal organ uptake after administration of a single dose. At 1, 2, 3, and 6 days after injection, (89)Zr-RG7356 uptake in MDA-MB-231 (CD44(+), resp) xenografts was nearly constant and about 9 times higher than in HepG2 (CD44(-), non-resp) xenografts (range 27.44 12.93 to 33.13 7.42% ID/g vs. 3.25 0.38 to 3.90 0.58% ID/g). Uptake of (89)Zr-RG7356 was similar in MDA-MB-231 (CD44(+), resp) and PL45 (CD44(+), non-resp) xenografts. Studies in monkeys revealed antibody uptake in spleen, salivary glands and bone marrow, which might be related to the level of CD44 expression. (89)Zr-RG7356 uptake in these normal organs decreased with increasing dose levels of unlabeled RG7356. (89)Zr-RG7356 selectively targets CD44(+) responsive and non-responsive tumors in mice and CD44(+) tissues in monkeys. These studies indicate the importance of accurate antibody dosing in humans to obtain optimal tumor targeting. Moreover, efficient binding of RG7356 to CD44(+) tumors may not be sufficient in itself to drive an anti-tumor response. PMID:24492295

  10. Preclinical electrogastrography in experimental pigs

    PubMed Central

    Kv?tina, Jaroslav; Varayil, Jithinraj Edakkanambeth; Ali, Shahzad Marghoob; Kune, Martin; Bure, Jan; Tachec, Ilja; Rejchrt, Stanislav; Kop?ov, Marcela

    2010-01-01

    Surface electrogastrography (EGG) is a non-invasive means of recording gastric myoelectric activity or slow waves from cutaneous leads placed over the stomach. This paper provides a comprehensive review of preclinical EGG. Our group recently set up and worked out the methods for EGG in experimental pigs. We gained our initial experience in the use of EGG in assessment of porcine gastric myoelectric activity after volume challenge and after intragastric administration of itopride and erythromycin. The mean dominant frequency in pigs is comparable with that found in humans. EGG in experimental pigs is feasible. Experimental EGG is an important basis for further preclinical projects in pharmacology and toxicology. PMID:21217873

  11. A multilevel study on the relationships between work characteristics, self-efficacy, collective efficacy, and organizational citizenship behavior: the case of Taiwanese police duty-executing organizations.

    PubMed

    Chen, Chun-Hsi Vivian; Kao, Rui-Hsin

    2011-01-01

    Public security, traffic management, and service for the people are the 3 major functions of policing in Taiwan. This definition encompasses not only the traditional job characteristics, but also the level of contextual characteristics and social characteristics because of police work's characteristics and its frequent interaction with the public. Thus, the present study conducted a multilevel model analysis by taking self-efficacy and collective efficacy as the mediating variables. The purpose was to investigate the influences of motivational work characteristics (knowledge-oriented) and social work characteristics (socially and contextually oriented) of work-design model on the police officers' organizational citizenship behavior (OCB), by using first-line police officers in Taiwan as the research objects. The study showed not only that knowledge characteristics will influence the self-efficacy of a police officer and that self-efficacy can in turn influence individual police officers' OCB, but also the contextual effect of social characteristics, contextual characteristics, and collective efficacy on self-efficacy and individuals' OCB. Additionally, there was a crosslevel moderating effect from contextual characteristics on the relationship between knowledge characteristics and self-efficacy and the relationship between self-efficacy and the individuals' OCB. The authors conclude the article with research implications. PMID:21834327

  12. Preclinical pharmacology and toxicology study of Ad-hTERT-E1a-Apoptin, a novel dual cancer-specific oncolytic adenovirus

    SciTech Connect

    Qi, Yanxin; Guo, Huanhuan; Hu, Ningning; He, Dongyun; Zhang, Shi; Chu, Yunjie; Huang, Yubin; Li, Xiao; Sun, LiLi; Jin, Ningyi

    2014-10-15

    Clinical studies have demonstrated that conditionally replicating adenovirus is safe. We constructed an oncolytic adenovirus, Ad-hTERT-E1a-Apoptin, using a cancer-specific promoter (human telomerase reverse transcriptase promoter, hTERTp) and a cancer cell-selective apoptosis-inducing gene (Apoptin). Ad-hTERT-E1a-Apoptin was proven effective both in vitro and in vivo in our previous study. In this study, the preclinical safety profiles of Ad-hTERT-E1a-Apoptin in animal models were investigated. At doses of 5.0 × 10{sup 8}, 2.5 × 10{sup 9}, and 1.25 × 10{sup 10} viral particles (VP)/kg, Ad-hTERT-E1a-Apoptin had no adverse effects on mouse behavior, muscle cooperation, sedative effect, digestive system, and nervous systems, or on beagle cardiovascular and respiratory systems at 5.0 × 10{sup 8}, 2.5 × 10{sup 9}, and 1.25 × 10{sup 10} VP/kg doses. In acute toxicity tests in mice, the maximum tolerated dose > 5 × 10{sup 10} VP/kg. There was no inflammation or ulceration at the injection sites within two weeks. In repeat-dose toxicological studies, the no observable adverse effect levels of Ad-hTERT-E1a-Apoptin in rats (1.25 × 10{sup 10} VP/kg) and beagles (2.5 × 10{sup 9} VP/kg) were 62.5- and 12.5-fold of the proposed clinical dose, respectively. The anti-virus antibody was produced in animal sera. Bone marrow examination revealed no histopathological changes. Guinea pigs sensitized by three repeated intraperitoneal injections of 1.35 × 10{sup 10} VP/mL Ad-hTERT-E1a-Apoptin each and challenged by one intravenous injection of 1.67 × 10{sup 8} VP/kg Ad-hTERT-E1a-Apoptin did not exhibit any sign of systemic anaphylaxis. Our data from different animal models suggest that Ad-hTERT-E1a-Apoptin is a safe anti-tumor therapeutic agent. - Highlights: • We use the rodents and non-rodents animal models to evaluation Ad-hTERT-E1a-Apoptin. • Ad-hTERT-E1a-Apoptin is a safe anti-tumor therapeutic agent. • Demonstrate the safety and feasibility dose of injected Ad-hTERT-E1a-Apoptin.

  13. Safety, Pharmacokinetic, and Efficacy Studies of Oral DB868 in a First Stage Vervet Monkey Model of Human African Trypanosomiasis

    PubMed Central

    Thuita, John K.; Wolf, Kristina K.; Murilla, Grace A.; Liu, Qiang; Mutuku, James N.; Chen, Yao; Bridges, Arlene S.; Mdachi, Raymond E.; Ismail, Mohamed A.; Ching, Shelley; Boykin, David W.; Hall, James Edwin; Tidwell, Richard R.; Paine, Mary F.; Brun, Reto; Wang, Michael Zhuo

    2013-01-01

    There are no oral drugs for human African trypanosomiasis (HAT, sleeping sickness). A successful oral drug would have the potential to reduce or eliminate the need for patient hospitalization, thus reducing healthcare costs of HAT. The development of oral medications is a key objective of the Consortium for Parasitic Drug Development (CPDD). In this study, we investigated the safety, pharmacokinetics, and efficacy of a new orally administered CPDD diamidine prodrug, 2,5-bis[5-(N-methoxyamidino)-2-pyridyl]furan (DB868; CPD-007-10), in the vervet monkey model of first stage HAT. DB868 was well tolerated at a dose up to 30 mg/kg/day for 10 days, a cumulative dose of 300 mg/kg. Mean plasma levels of biomarkers indicative of liver injury (alanine aminotransferase, aspartate aminotransferase) were not significantly altered by drug administration. In addition, no kidney-mediated alterations in creatinine and urea concentrations were detected. Pharmacokinetic analysis of plasma confirmed that DB868 was orally available and was converted to the active compound DB829 in both uninfected and infected monkeys. Treatment of infected monkeys with DB868 began 7 days post-infection. In the infected monkeys, DB829 attained a median Cmax (dosing regimen) that was 12-fold (3 mg/kg/day for 7 days), 15-fold (10 mg/kg/day for 7 days), and 31-fold (20 mg/kg/day for 5 days) greater than the IC50 (14 nmol/L) against T. b. rhodesiense STIB900. DB868 cured all infected monkeys, even at the lowest dose tested. In conclusion, oral DB868 cured monkeys with first stage HAT at a cumulative dose 14-fold lower than the maximum tolerated dose and should be considered a lead preclinical candidate in efforts to develop a safe, short course (57 days), oral regimen for first stage HAT. PMID:23755309

  14. Development of an in vitro model for the simultaneous study of the efficacy and hematotoxicity of antileukemic compounds.

    PubMed

    Valeri, Antonio; Alonso-Ferrero, Mara Eugenia; Cerrato, Laura; Martnez, Sandra; Bueren, Juan A; Albella, Beatriz

    2010-12-15

    Hematopoietic system displays a wide spectrum of cell populations hierarchically organized in the bone marrow. Homeostasis in this system requires equilibrium between the self-renewal of the stem cells and their capacity of differentiation. Any failure on this equilibrium could lead to fatal consequences, such as the development of leukemia. Due to its rapid rate of renewal, hematopoietic tissue is a major target for antitumoral compounds and often becomes a dose limiting factor in the development of antineoplastics. Our aim was to develop an in vitro model for predicting the efficacy of antitumoral compounds on leukemic cells and their toxic effects on the healthy hematopoietic cells. The mouse myelomonocytic leukemia WEHI-3b was transduced with a lentiviral vector for expressing the green fluorescence protein. Mixed semisolid clonogenic cultures of transduced WEHI-3b and murine bone marrow cells were exposed to five pharmaceuticals: daunorubicin (positive control), atropine sulphate (negative control) and three in different stages of clinical development (trabectedin, Zalypsis() and PM01183). Colonies of leukemic cells were distinguishable from healthy CFU-GM under fluorescence microscope. The sensitivity of leukemic cells to daunorubicin, trabectedin, Zalypsis() and PM01183 was higher compared to healthy cells. The effect of a non-antitumoral compound, atropine sulphate, was the same on both populations. Our results show that this in vitro model is a valuable tool for studying the effect of antitumoral compounds in both tumoral and normal hematopoietic cells under the same toxic microenvironment and could safe time and facilitate the reduction of the number of animals used in preclinical development of pharmaceuticals. PMID:20883753

  15. The Relationship between Pedagogical Beliefs and Teacher Efficacy: A Case Study of Chinese Foreign Language Teachers in Texas

    ERIC Educational Resources Information Center

    Liu, I-Chun

    2012-01-01

    This study investigated an emerging language learning culture by examining the relationship between teachers' pedagogical beliefs and perceived efficacy in two cities in southern Texas. Drawing on Bandura's (1994) theory of self-efficacy and Ashton and Webb's (1986) notions about teacher efficacy, a multi-sited case study was

  16. Teaching Induction: A Study on the Effectiveness of Induction Programs among Urban High School Teacher Self-Efficacy

    ERIC Educational Resources Information Center

    Lowrey, Jason H.

    2012-01-01

    The purpose of this study is to examine the impact that induction programs have on self-efficacy of new teachers in urban, Midwestern high schools. Because induction programs have been used to measure elements of new teacher self-efficacy, it remains important to study this topic, and explore the information in an urban setting where self-efficacy

  17. Advances in Preclinical SPECT Instrumentation

    PubMed Central

    Peterson, Todd E.; Shokouhi, Sepideh

    2012-01-01

    Preclinical SPECT imaging of rodents is both in demand and very demanding. The need for high spatial resolution in combination with good sensitivity has given rise to considerable innovation in the areas of detectors, collimation, acquisition geometry, and image reconstruction. Some of the developments described herein are beginning to carry over into clinical imaging as well. PMID:22586145

  18. Translational research for Parkinson?s disease: The value of pre-clinical primate models.

    PubMed

    Aron Badin, Romina; Vadori, Marta; Cozzi, Emanuele; Hantraye, Philippe

    2015-07-15

    Animal models have been highly questioned for their ability to predict the efficacy of different therapeutic strategies for neurodegenerative diseases. The increasing number of phase I/II clinical trials that fail to proceed to further stages of drug development has discredited the pertinence of such investigations. However, critical analysis of the data has often revealed errors and partially explained the lack of efficacy, opening the way to a refinement in designing pre-clinical studies. In parallel, many promising methods of drug delivery to the brain such as gene therapy or cell therapy have considerably advanced thanks to the clinical failures in the past 10 years. As methodological advances appear and knowledge becomes available, scientists will be faced with the choice of how to test new strategies or re-test old ones. With the hardening of social views and legislation regarding animal experimentation, there is increasing pressure to find alternative methods of assessment that predict efficacy (such as computational based models), or to perform efficacy trials directly in patients and only safety assays in animals. In this review we will focus on Parkinson?s disease and on the impact of a body of data issued from NHP studies. We will attempt to critically examine the advantages and limitations of various approaches from the perspective of the animal model used to address specific questions. PMID:25841877

  19. Recruitment for an efficacy study in chemoprevention--the Concerned Smoker Study.

    PubMed

    Arnold, A; Johnstone, B; Stoskopf, B; Skingley, P; Browman, G; Levine, M; Hryniuk, W

    1989-09-01

    Efficacy studies are important for the development of long-term cancer prevention strategies. Recruitment aims for a highly motivated group of participants. The Concerned Smoker Study is aimed at smokers with at least a 15 pack-year history and bronchial atypia on sputum sampling Recruitment has been primarily through use of the media. During the first year of randomization 905 potential participants expressed interest. Of these, 80 were eventually randomized. With over 60 participants having completed the study only one has defaulted and compliance with the study protocol has been high. Participants became aware of the study through the following sources: daily newspaper 36.6%, weekly newspaper 16.2%, television 14.9%, radio 13.8%, community television 1.3%, other sources 13.3%. Over 90% of potential participants who initially express interest in such a chemoprevention project may not ultimately be suitable. The population chosen for such studies may not be very representative of the more general population; however, a high degree of compliance can be obtained which will provide valuable information on treatment efficacy. PMID:2694164

  20. Comparative study of the neurotrophic effects elicited by VEGF-B and GDNF in preclinical in vivo models of Parkinson's disease.

    PubMed

    Yue, X; Hariri, D J; Caballero, B; Zhang, S; Bartlett, M J; Kaut, O; Mount, D W; Wllner, U; Sherman, S J; Falk, T

    2014-01-31

    Vascular endothelial growth factor B (VEGF-B) has recently been shown to be a promising novel neuroprotective agent for several neurodegenerative conditions. In the current study we extended previous work on neuroprotective potential for Parkinson's disease (PD) by testing an expanded dose range of VEGF-B (1 and 10 ?g) and directly comparing both neuroprotective and neurorestorative effects of VEGF-B in progressive unilateral 6-hydroxydopamine (6-OHDA) PD models to a single dose of glial cell line-derived neurotrophic factor (GDNF, 10 ?g), that has been established by several groups as a standard in both preclinical PD models. In the amphetamine-induced rotational tests the treatment with 1 and 10 ?g VEGF-B resulted in significantly improved motor function of 6-OHDA-lesioned rats compared to vehicle-treated 6-OHDA-lesioned rats in the neuroprotection paradigm. Both doses of VEGF-B caused an increase in tyrosine hydroxylase (TH)-positive cell and fiber count in the substantia nigra (SN) and striatum in the neuroprotective experiment. The effect size was comparable to the effects seen with GDNF. In the neurorestoration paradigm, VEGF-B injection had no significant effect in either the behavioral or the immunohistochemical analyses, whereas GDNF injection significantly improved the amphetamine-induced rotational behavior and reduced TH-positive neuronal cell loss in the SN. We also present a strong positive correlation (p=1.9e-50) of the expression of VEGF-B with nuclear-encoded mitochondrial genes involved in fatty acid metabolism in rat midbrain, pointing to the mitochondria as a site of action of VEGF-B. GDNF showed a positive correlation with nuclear-encoded mitochondrial genes that was not nearly as strong (p=0.018). VEGF-B counteracted rotenone-induced reduction of (a) fatty acid transport protein 1 and 4 levels and (b) both Akt protein and phosphorylation levels in SH-SY5Y cells. We further verified VEGF-B expression in the human SN pars compacta of healthy controls and PD patients, in neuronal cells that show co-expression with neuromelanin. These results have demonstrated that VEGF-B has potential as a neuroprotective agent for PD therapy and should be further investigated. PMID:24291725

  1. Preclinical immunogenicity and functional activity studies of an A+W meningococcal outer membrane vesicle (OMV) vaccine and comparisons with existing meningococcal conjugate- and polysaccharide vaccines.

    PubMed

    Tunheim, G; Arnemo, M; Næss, L M; Fjeldheim, Å K; Nome, L; Bolstad, K; Aase, A; Mandiarote, A; González, H; González, D; García, L; Cardoso, D; Norheim, G; Rosenqvist, E

    2013-12-01

    Meningococci of serogroups A and W (MenA and MenW) are the main causes of epidemic bacterial meningitis outbreaks in sub-Saharan Africa. In this study we prepared a detergent extracted outer membrane vesicle (dOMV) vaccine from representative African MenA and MenW strains, and compared the immunogenicity of this vaccine with existing meningococcal conjugate and polysaccharide (PS) vaccines in mice. NMRI mice were immunized with preclinical batches of the A+W dOMV vaccine, or with commercially available vaccines; a MenA conjugate vaccine (MenAfriVac(®), Serum Institute of India), ACYW conjugate vaccine (Menveo(®), Novartis) or ACYW PS vaccine (Mencevax(®), GlaxoSmithKline). The mice received 2 doses of 1/10 or 1/50 of a human dose with a three week interval. Immune responses were tested in ELISA, serum bactericidal activity (SBA) and opsonophagocytic activity (OPA) assays. High levels of IgG antibodies against both A and W dOMV were detected in mice receiving the A+W dOMV vaccine. High SBA titers against both MenA and MenW vaccine strains were detected after only one dose of the A+W dOMV vaccine, and the titers were further increased after the second dose. The SBA and OPA titers in mice immunized with dOMV vaccine were significantly higher than in mice immunized with the ACYW-conjugate vaccine or the PS vaccine. Furthermore, the A+W dOMV vaccine was shown to induce SBA and OPA titers against MenA of the same magnitude as the titers induced by the A-conjugate vaccine. In conclusion, the A+W dOMV vaccine induced high levels of functional antibodies to both MenA and MenW strains, levels that were shown to be higher or equal to the levels induced by licensed meningococcal vaccines. Thus, an A+W dOMV vaccine could potentially serve as an alternative or a supplement to existing conjugate and PS vaccines in the African meningitis belt. PMID:24120679

  2. Comparative study of the neurotrophic effects elicited by VEGF-B and GDNF in preclinical in vivo models of Parkinsons disease

    PubMed Central

    Yue, Xu; Hariri, Dana J.; Caballero, Beatrice; Zhang, Shiling; Bartlett, Mitchell J.; Kaut, Oliver; Mount, David W.; Wllner, Ullrich; Sherman, Scott J.; Falk, Torsten

    2014-01-01

    Vascular endothelial growth factor B (VEGF-B) has recently been shown to be a promising novel neuroprotective agent for several neurodegenerative conditions. In the current study we extended previous work on neuroprotective potential for Parkinsons disease (PD) by testing an expanded dose range of VEGF-B (1 ?g and 10 ?g) and directly comparing both neuroprotective and neurorestorative effects of VEGF-B in progressive unilateral 6-hydroxydopamine (6-OHDA) PD models to a single dose of glial cell line-derived neurotrophic factor (GDNF, 10 ?g), that has been established by several groups as a standard in both preclinical PD models. In the amphetamine-induced rotational tests the treatment with 1 and 10 ?g VEGF-B resulted in significantly improved motor function of 6-OHDA-lesioned rats compared to vehicle-treated 6-OHDA-lesioned rats in the neuroprotection paradigm. Both doses of VEGF-B caused an increase in tyrosine hydroxylase (TH)-positive cell and fiber count in the substantia nigra (SN) and striatum in the neuroprotective experiment. The effect size was comparable to the effects seen with GDNF. In the neurorestoration paradigm, VEGF-B injection had no significant effect in either the behavioral or the immunohistochemical analyses, whereas GDNF injection significantly improved the amphetamine-induced rotational behavior and reduced TH-positive neuronal cell loss in the SN. We also present a strong positive correlation (p = 1.9 e-50) of the expression of VEGF-B with nuclear-encoded mitochondrial genes involved in fatty acid metabolism in rat midbrain, pointing to the mitochondria as a site of action of VEGF-B. GDNF showed a positive correlation with nuclear-encoded mitochondrial genes that was not nearly as strong (p = 0.018). VEGF-B counteracted rotenone-induced reduction of (a) fatty acid transport protein 1 and 4 levels and (b) both Akt protein and phosphorylation levels in SH-SY5Y cells. We further verified VEGF-B expression in the human SN pars compacta of healthy controls and Parkinsons disease patients, in neuronal cells that show co-expression with neuromelanin. These results have demonstrated that VEGF-B has potential as a neuroprotective agent for PD therapy a