Melflufen (melphalan flufenamide, chemical name L-melphalanyl-p-L-fluorophenylalanine ethyl ester hydrochloride, previously called J1) is a derivative of the classical alkylating agent melphalan. Melflufen is potentiated by hydrolytic cleavage by aminopeptidase N (APN), leading to high intracellular concentrations of alkylating moieties and subsequent cell death. Increased APN expression is associated with the malignant phenotype of several human cancers, including acute myeloid leukemia, lymphoma and ovarian cancer, and plays a functional role in tumor angiogenesis. Therefore investigations of melflufen activity in these malignancies as well as detailed studies of inhibition of angiogenesis are interesting. The aim of this project was to investigate the cytotoxic and antiangiogenic effect, in vitro and in vivo, of melflufen, compared to melphalan and other cytotoxic drugs used in the clinic. We showed that melflufen was more effective than its parental drug melphalan in lymphoma, AML and ovarian cancer in cell lines as well as in primary patient samples. An improved in vitro therapeutic index was demonstrated by an increased cytotoxic activity in the patient samples compared to normal peripheral blood mononuclear cells (PBMCs). Furthermore, melflufen in combination with cytarabine was synergistic in an AML cell line in a sequence-dependent manor. Melflufen was shown effective in several animal models using lymphoma, AML and ovarian cell xenografts (single drug or in combination), including an intraperitoneal ovarian xenograft. Finally, we demonstrated that melflufen had antiangiogenic properties in several different models.

Chun Sing Chu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 139-149). / Acknowledgements --- p.i / Abstract --- p.ii / Abbreviations --- p.vi / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter Chapter 2 --- "Development of Polyclonal Antibodies against 5α-Estrane-3β,17α-diol" / Chapter 2.1 --- Introduction --- p.39 / Chapter 2.2 --- Materials and Methods --- p.45 / Chapter 2.3 --- Results --- p.55 / Chapter 2.4 --- Discussion --- p.64 / Chapter Chapter 3 --- "Development of Monoclonal Antibodies against 5α-Estrane-3β,17α-diol" / Chapter 3.1 --- Introduction --- p.69 / Chapter 3.2 --- Materials and Methods --- p.86 / Chapter 3.3 --- Results --- p.107 / Chapter 3.4 --- Discussion --- p.126 / Chapter Chapter 4 --- General Conclusion --- p.134 / References --- p.139

A novel Y-90 liquid brachytherapy strategy is currently being studied for the treatment of osteosarcoma using a preclinical translational model in dogs to assess its potential efficacy and toxicity. In this study, dosimetry calculations are performed for Y-90 liquid brachytherapy in a dog with osteosarcoma using the Geant4 Monte Carlo code. A total of 611.83 MBq Y-90 radiopharmaceutical is administered via direct injections, and the in vivo distribution of Y-90 is assessed using a time-of-flight (TOF) PET/CT scanner. A patient-specific geometry is built using anatomical data obtained from CT images. The material properties of tumor and surrounding tissues are calculated based on a CT number - electron density calibration. The Y-90 distribution is sampled in Geant4 from PET images using a collapsing 3-D rejection technique to determine the decay sites. Dose distributions in the tumor bed and surrounding tissues are calculated demonstrating significant heterogeneity with multiple hot spots at the injection sites. Dose volume histograms show about 33.9 percent of bone and tumor and 70.2 percent of bone marrow and trabecular bone receive a total dose over 200 Gy; about 3.2 percent of bone and tumor and 31.0 percent of bone marrow and trabecular bone receive a total dose of over 1000 Gy. Y-90 liquid brachytherapy has the potential to be used as an adjuvant therapy or for palliation purposes. Future work includes evaluation of pharmacokinetics of the Y-90 radiopharmaceutical, calibration of PET/CT scanners for the direct quantitative assessment of Y-90 activity concentration, and assessment of efficacy of the Y-90 liquid brachytherapy strategy.

Thesis (Ph.D.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 139 pages. Includes Vita. Includes bibliographical references.

Multicenter preclinical studies have been suggested as a method to improve potential clinical translation of preclinical work by testing reproducibility and generalizability of findings. In these studies, multiple independent laboratories collaboratively conduct a research experiment using a shared protocol. The use of a multicenter design in preclinical experimentation is a recent approach and only a handful of these studies have been published. In this thesis, I aimed to provide insight into preclinical multicenter studies by 1) systematically synthesizing all published preclinical multicenter studies; and 2) exploring the experiences of, barriers and enablers to, and the extent of collaboration within preclinical multicenter studies. In Part One, I conducted a systematic review of preclinical multicenter studies. The database searches identified 3150 citations and 13 studies met inclusion criteria. The multicenter design was applied across a diverse range of diseases including stroke, heart attack, and traumatic brain injury. The median number of centers was 4 (range 2-6) and the median sample size was 133 (range 23-384). Most studies had lower risk of bias and higher completeness of reporting than typically seen in single-centered studies. Only five of the thirteen studies produced results consistent with previous single-center studies, highlighting a central concern of preclinical research: irreproducibility and poor generalizability of findings from single laboratories. In Part Two, I performed semi-structured interviews with researchers who have been involved in a preclinical multicenter study. Braun and Clarkes’ thematic analysis was used to identify emerging themes, and the extent of collaboration was evaluated using an established theory of collaboration developed by Wood and Gray. Twelve researchers from 6 studies were interviewed. Most participants indicated that funding and the culture of the scientific community were barriers, and that established relationships and transparency with collaborators were enablers to multicenter studies. Some participants felt that a harmonized protocol was optimal, while others stated that variability in the protocol across sites was more appropriate. Most participants indicated that multicenter studies had a purpose and place in preclinical research. My findings also suggest that multicenter preclinical studies may provide a method to robustly assess therapies prior to considering clinical translation. These insights will allow for more effective planning and execution of future preclinical multicenter projects and may support the development of best practices and guidelines.

Background: Construct validity refers to the degree to which tests that claim to measure a “construct” (i.e., an inferred concept that is intangible regarding an individual’s health or internal state such as a disease, or postulated attribute) are truly reflective of that specific construct. It is suggested that construct validity is an important concept in preclinical research, as it may help reduce misinterpretations of study results allowing for better ability to predict the success of clinical translation of preclinical studies. However, there is a lack of empirical evidence to confirm its impact on preclinical research efficacy. Objectives: (I) Conduct a scoping review of the construct validity literature as it relates to the design of in vivo animal studies. (II) Conduct an overview of systematics reviews evaluating the application and reporting of construct validity within systematic reviews of in vivo animal studies. Methods: For the scoping review, we searched Embase, MEDLINE, and Google Scholar. Eligibility criteria was intentionally broad as we included any article that mentioned construct validity in preclinical in vivo research. Further review of citations was performed on eligible studies that provided substantial discussion on construct validity. For the overview, we searched MEDLINE, Embase, and TOXLINE for systematic reviews of preclinical in vivo interventions. The outcomes of interest were the prevalence of systematic reviews that mentioned construct validity and the prevalence of reviews that assessed construct validity. Results: The literature searches for the scoping and overview yielded 3657 and 2356 articles, respectively. After screening 372 and 444 met inclusion criteria for the scoping and overview. Six codes were generated (theory; mechanism; matches the human condition; measures what it reports to; experimental conditions; and outcomes) from the content analysis for the definition of construct validity. Of the 444 systematic reviews, seven mentioned construct validity, but only three used the term construct validity directly. None of the systematic reviews assessed construct validity. Discussion/Conclusion: Construct validity was not defined uniformly among studies suggesting it is not clearly understood. There was limited reporting on construct validity in systematic reviews and entirely no assessment of it; this may reflect a lack of awareness of this concept. Future research should aim to find a consensus on the definition of construct validity in order to develop tools and frameworks to help researchers assess construct validity.

Indiana University-Purdue University Indianapolis (IUPUI) / Anxiety disorders are the most common class of mental disorders in the United States, and they both promote and exacerbate disorders of substance abuse. Mounting evidence of sex differences in the relationship between anxiety disorders and alcoholism supports the potential existence of an anxiety-dependent vulnerability to alcohol abuse in women compared with men. One potential point of overlap in the physiological systems involved in anxiety response and reward processing is the amygdala. Here, a model of chronic stress in rodents was employed to probe changes in the electrophysiological and biochemical properties of the amygdala at a post-stress baseline and during a post-stress first exposure to alcohol. Electrophysiological data revealed that neurons in the centromedial amygdala were more responsive to stimulation in the basolateral amygdala in females compared with males, but a history of chronic stress altered the female response to match that of males with or without a history of chronic stress. Protein analysis of postsynaptic glutamatergic receptor expression and phosphorylation in the amygdala did not indicate any differences based on sex or exposure to stress or alcohol. These data demonstrate a sex difference in stress-induced alterations in amygdala circuitry and indicate a potential role for this circuitry in the comorbidity of anxiety disorders and alcoholism.

Horimatsu T, Muto M, Yoda Y, Yano T, Ezoe Y, et al. (2012) Tissue Damage in the Canine Normal Esophagus by Photoactivation with Talaporfin Sodium (Laserphyrin): A Preclinical Study. PLoS ONE 7(6): e38308. doi:10.1371/journal.pone.0038308 / 京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第12870号 / 論医博第2086号 / 新制||医||1006(附属図書館) / 31588 / (主査)教授 羽賀 博典, 教授 坂井 義治, 教授 平岡 眞寛 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

Synapsins are primarily neuron-specific proteins critical for neurotransmission, synaptogenesis and synapse maintenance. Synapsin II has been specifically linked with increased susceptibility towards developing schizophrenia. Reduced synapsin II mRNA levels were found in the dorsolateral prefrontal cortex (PFC) of patients with schizophrenia. Moreover, synapsin II knockdown in the medial PFC (mPFC) of the adult rat was previously shown to cause schizophrenia-like behaviour and altered expression levels of vesicular proteins involved in glutamatergic and GABAergic signaling within the mPFC. The study of schizophrenia in recent years has shifted to focus on neurodevelopmental players which influence disease outcome. This study was designed to establish the link between neurodevelopmental dysregulation of synapsin II and schizophrenia. Specific knockdown of synapsin II was performed in the mPFC at postnatal day (PD) 7 and PD 17-23. Schizophrenia-like behavioural abnormalities were assessed at pre-pubertal (PD 32-35) and post-pubertal (PD 65-70) stages. Protein estimation of vesicular transporters involved in glutamate, GABA, and dopamine neurotransmitter systems were also assessed in the mPFC. Results from this study indicate (1) synapsin II knockdown during PD 17-23, but not PD 7, caused lasting schizophrenia-like abnormalities (2) abnormalities exhibited permanence at pre-pubertal and post-pubertal stages, and manifested as a function of brain development, (3) behavioural abnormalities were reminiscent of symptoms in established animal models of schizophrenia (i.e. deficits in prepulse inhibition, social withdrawal, locomotor hyperactivity), (4) neurodevelopmental synapsin II alterations induced hypoactive glutamatergic activity through decreased synapsin IIa expression levels (pre-pubertal) and decreased VGLUT-2 expression levels (post-pubertal), and (5) acute olanzapine treatment effectively attenuated schizophrenia-like abnormalities through normalized synapsin IIa expression levels (pre-pubertal) and increased GAD65/67 expression levels (post-pubertal). Results show the causal link between synapsin II expression during critical neurodevelopmental stages and schizophrenia. Additionally, evidence has been provided for the face, construct, and predictive validities of this newly developed animal model of schizophrenia. / Thesis / Doctor of Philosophy (PhD)

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