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Rebuilding of infarcted myocardium by mesenchymal stem cells (MSCs) has not been successful because of poor cell survival due in part to insufficient blood supply after myocardial infarction (MI). We hypothesize that targeted delivery of vascular endothelial growth factor (VEGF) to MI can help regenerate vasculature in support of MSC therapy in a rat model of MI. VEGF-encapsulated immunoliposomes targeting overexpressed P-selectin in MI tissue were infused by tail vein immediately after MI. One week later, MSCs were injected intramyocardially. The cardiac function loss was moderated slightly by targeted delivery of VEGF or MSC treatment. Targeted VEGF+MSC combination treatment showed highest attenuation in cardiac function loss. The combination treatment also increased blood vessel density (80%) and decreased collagen content in post-MI tissue (33%). Engraftment of MSCs in the combination treatment group was significantly increased and the engrafted cells contributed to the restoration of blood vessels. From the Clinical Editor VEGF immunoliposomes targeting myocardial infarction tissue resulted in significantly higher attenuation of cardiac function loss when used in combination with mesenchymal stem cells. MSCs were previously found to have poor ability to restore cardiac tissue, likely as a result of poor blood supply in the affected areas. This new method counterbalances that weakness by the known effects of VEGF, as demonstrated in a rat model.

GM2 gangliosidoses, including Tay–Sachs disease and Sandhoff disease, are lysosomal storage disorders caused by deficiencies in β-N-acetylhexosaminidase (Hex). Patients are afflicted primarily with progressive central nervous system (CNS) dysfunction. Studies in mice, cats, and sheep have indicated safety and widespread distribution of Hex in the CNS after intracranial vector infusion of AAVrh8 vectors encoding species-specific Hex α- or β-subunits at a 1:1 ratio. Here, a safety study was conducted in cynomolgus macaques (cm), modeling previous animal studies, with bilateral infusion in the thalamus as well as in left lateral ventricle of AAVrh8 vectors encoding cm Hex α- and β-subunits. Three doses (3.2 × 1012 vg [n = 3]; 3.2 × 1011 vg [n = 2]; or 1.1 × 1011 vg [n = 2]) were tested, with controls infused with vehicle (n = 1) or transgene empty AAVrh8 vector at the highest dose (n = 2). Most monkeys receiving AAVrh8-cmHexα/β developed dyskinesias, ataxia, and loss of dexterity, with higher dose animals eventually becoming apathetic. Time to onset of symptoms was dose dependent, with the highest-dose cohort producing symptoms within a month of infusion. One monkey in the lowest-dose cohort was behaviorally asymptomatic but had magnetic resonance imaging abnormalities in the thalami. Histopathology was similar in all monkeys injected with AAVrh8-cmHexα/β, showing severe white and gray matter necrosis along the injection track, reactive vasculature, and the presence of neurons with granular eosinophilic material. Lesions were minimal to absent in both control cohorts. Despite cellular loss, a dramatic increase in Hex activity was measured in the thalamus, and none of the animals presented with antibody titers against Hex. The high overexpression of Hex protein is likely to blame for this negative outcome, and this study demonstrates the variations in safety profiles of AAVrh8-Hexα/β intracranial injection among different species, despite encoding for self-proteins.

Proton magnetic resonance spectroscopy has emerged as one of the most informative neuroimaging modalities for studying the effect of HIV infection in the brain, providing surrogate markers by which to assess disease progression and monitor treatment. Reductions in the level of N-Acetylaspartate and N-Acetylaspartate/creatine are established markers of neuronal injury or loss. However, the biochemical basis of altered creatine levels in neuroAIDS is not well understood. This study used a rapid progression macaque model of neuroAIDS to elucidate the changes in creatine. As the disease progressed, proton magnetic resonance spectroscopy revealed a decrease in N-Acetylaspartate, indicative of neuronal injury, and an increase in creatine yet to be elucidated. Subsequently, immunohistochemistry and stereology measures of decreased synaptophysin, microtubule-associated protein 2, and neuronal density confirmed neuronal injury. Furthermore, increases in ionized calcium binding adaptor molecule 1 and glial fibrillary acidic protein indicated microglial and astroglial activation, respectively. Given these data, elevated creatine may reflect enhanced high-energy phosphate turnover in highly metabolizing activated astrocytes and microglia. Magn Reson Med, 2011. © 2011 Wiley-Liss, Inc.

Research has shown that ~ 25% - 30% breast cancers overexpress Her-2/neu receptor. The major problem in the management of Her-2/neu overexpressed breast cancer is its multi-drug resistantce (MDR). P-glycoprotein (P-gp) mediated MDR has been recognized as one of the major mechanisms in drug resistance in breast cancer. Therefore, developing a breast cancer cell line with both Her-2/neu and MDR positive becomes necessary. Dual positive breast cancer cell line was developed by transfection of the multidrug resistance gene (MDR1 gene) to human breast carcinoma cell line BT-474 (Her-2/neu +), followed by selection on clochicine. The presence of membrane protein Her-2 and P-gp were tested by immunohistochemical methods. The multidrug resistance was tested by the treatment efficacy of doxorubicin. The overexpression of p-glycoprotein in multidrug resistant cells and the presence of membrane protein Her-2 were confirmed by immunocytochemistry staining as well as Western Blot. Fluorescence imaging study showed tha...

The stem cell therapy to treat myocardial infarction (MI) has shown disappointed results largely due to the poor survival of transplanted stem cells in the MI region. We propose a combination therapy by targeted delivery of a proangiogenic compound, vascular endothelial growth factor (VEGF), to MI region to improve the micro-environment, which may enhance the survival of transplanted stem cells, and further improve the cardiac function. In this study, P-selectin conjugated immunoliposomes containing VEGF were given to the MI rats through tail vein injection immediately after surgery. Mesenchymal stem cells (MSCs) were transplanted to the MI region one week later. Left ventricular percent fractional shortening were measured 1 week and 4 weeks post MI using echocardiography. Results indicate that MI rats with no treatment lost 8% contractility (∼40% of its heart function) from 1 week to 4 weeks post-MI. Either targeted VEGF or MSCs treatment alone can slow down the loss by half to 4%. The combination of targeted VEGF and MSCs treatment further decreased the contractility loss to 0.7%. In conclusion, the combination treatment of targeted VEGF and MSCs results in a larger recovery in cardiac function compared to either targeted VEGF or stem cell treatment alone.

There is a critical need for animal models to study aspects type 2 diabetes mellitus pathogenesis and prevention. While the rhesus macaque is such an established model, the common marmoset has added benefits including reduced zoonotic risks, shorter life span, and a predisposition to birth twins demonstrating chimerism. The marmoset as a model organism for the study of metabolic syndrome has not been fully evaluated. Marmosets fed high-fat or glucose-enriched diets were followed longitudinally to observe effects on morphometric and metabolic measures. Effects on pancreatic histomorphometry and vascular pathology were examined terminally. The glucose–enriched diet group developed an obese phenotype and a prolonged hyperglycemic state evidenced by a rapid and persistent increase in mean glycosylated hemoglobin (HgbA1c) observed as early as week 16. In contrast, marmosets fed a high-fat diet did not maintain an obese phenotype and demonstrated a delayed increase in HgbA1c that did not reach statistical significance until week 40. Consumption of either diet resulted in profound pancreatic islet hyperplasia suggesting a compensation for increased insulin requirements. Although the high fat diet group developed atherosclerosis of increased severity, the presence of lesions correlated with glucose intolerance only in the glucose-enriched diet group. The altered timing of glucose dysregulation, differential contribution to obesity, and variation in vascular pathology suggests mechanisms of effect specific to dietary nutrient content. Feeding nutritionally modified diets to common marmosets recapitulates aspects of metabolic disease and represents a model that may prove instrumental to elucidating the contribution of nutrient excess to disease development.

Diagnosis: Rat bite fever (RBF) due to Streptobacillus moniliformis. A Gram stain showed highly pleomorphic, gram-negative rods that were identified as S. moniliformis (figure l).The patient was given a regimen of penicillin (2 million U every 4 h intravenously). RBF has been associated with serious sequelae, such as endocarditis, hepatitis, meningitis, and nephritis. The patient did not meet Duke's criteria for diagnosis of endocarditis [1]. A transthoracic echocardiogram did not show vegetations. There was no evidence of involvement of other organs. Subsequent blood cultures showed no growth. The patient was treated with 7 days of intravenous penicillin, followed by 7 days of oral penicillin. She remained afebrile, no new skin eruptions appeared, and all residual lesions desquamated and healed. She did not return for her scheduled follow-up appointment. In a telephone interview that was conducted a week after she finished her course of penicillin, she stated that she had mild arthralgias but otherwise felt well, with no new skin eruptions. Six months after the initial presentation, the cryoglobulinemia had resolved, the antinuclear antibody titer had decreased to 1:40, and the patient remained symptom free. More than 2 million animal bites are reported each year in the United States, of which 1b% are attributable to rats [2]. t e ited States, of ic ~-1 are attributable to rats [2]. Although RBF is considered to be a rare illness, it is likely that it is underdiagnosed. S. moniliformis is found in the nasopharynx of most rats and is excreted in their urine. Nasopharyngeal carriage rates in healthy laboratory rats range from 10% to 100%; rates among wild rats have been estimated at 50%-100% [2]. The organism is usually transmitted by a bite or scratch from an infected animal, but it may also be acquired by simply handling the animal or from exposure to rat urine when handling cage materials [2]. On further questioning, the patient mentioned that she regularly cleaned the cages of all of her animals. She also informed us that she let her pet rats lick her teeth! RBF is characterized by the acute onset of shaking chills, fever, vomiting, and severe myalgias. After a few days, a maculopapular skin eruption appears, followed by arthralgias in up to 50% of cases. The eruption is usually seen on the extensor surface of the extremities and frequently involves the palms and soles. It can also be petechial, purpuric, or pustular and lasts for -3 weeks. Approximately 20% of the rashes undergo desquamation [3]. Usually the illness is self-limited. However, in a small number of untreated cases, serious sequelae, such as meningitis, endocarditis, hepatitis, nephritis, and brain or joint abscess may develop, with a mortality rate of 13% [4], increasing to 53% in cases with cardiac involvement [5]. Nineteen cases of S. moniliformis endocarditis have been reported; these cases occurred predominantly in patients with previously damaged heart valves [5, 6]. However, RBF is not a reportable disease, and the actual incidence of endocarditis associated with RBF is not known.