Cryopreservation effect on sperm viability, mitochondrial membrane potential, acrosome integrity and sperm capacitation of alpaca spermatozoa detected by imaging flow cytometry.

Eighty-five sperm samples were cryopreserved and SYBR14/PI, MitoTracker Deep Red FM, FITC-PSA/PI and chlortetracycline were used for imaging flow cytometry evaluation of sperm viability, mitochondrial membrane potential (MMP), acrosome integrity and sperm capacitation, respectively. Sperm motility was also registered. Sperm motility (46.

The optimal F-fluoromisonidazole PET threshold to define tumor hypoxia in preclinical squamous cell carcinomas using pO electron paramagnetic resonance imaging as reference truth.

Purpose: To identify the optimal threshold in F-fluoromisonidazole (FMISO) PET images to accurately locate tumor hypoxia by using electron paramagnetic resonance imaging (pO EPRI) as ground truth for hypoxia, defined by pO [Formula: see text] 10 mmHg.

Methods: Tumor hypoxia images in mouse models of SCCVII squamous cell carcinoma (n = 16) were acquired in a hybrid PET/EPRI imaging system 2 h post-injection of FMISO. T2-weighted MRI was used to delineate tumor and muscle tissue.

A Model for Studying the Biomechanical Effects of Varying Ratios of Collagen Types I and III on Cardiomyocytes.

Purpose: To develop a novel model composed solely of Col I and Col III with the lower and upper limits set to include the ratios of Col I and Col III at 3:1 and 9:1 in which the structural and mechanical behavior of the resident CM can be studied. Further, the progression of fibrosis due to change in ratios of Col I:Col III was tested.

Methods: Collagen gels with varying Col I:Col III ratios to represent a healthy (3:1) and diseased myocardial tissue were prepared by manually casting them in wells.

3D Bioprinting of cardiac tissue and cardiac stem cell therapy.

Cardiovascular tissue engineering endeavors to repair or regenerate damaged or ineffective blood vessels, heart valves, and cardiac muscle. Current strategies that aim to accomplish such a feat include the differentiation of multipotent or pluripotent stem cells on appropriately designed biomaterial scaffolds that promote the development of mature and functional cardiac tissue. The advent of additive manufacturing 3D bioprinting technology further advances the field by allowing heterogenous cell types, biomaterials, and signaling factors to be deposited in precisely organized geometries similar to those found in their native counterparts.

Magnetic Resonance Imaging and Molecular Characterization of a Hormone-Mediated Murine Model of Prostate Enlargement and Bladder Outlet Obstruction.

Urinary complications resulting from benign prostatic hyperplasia and bladder outlet obstruction continue to be a serious health problem. Novel animal model systems and imaging approaches are needed to understand the mechanisms of disease initiation, and to develop novel therapies for benign prostatic hyperplasia. Long-term administration of both estradiol and testosterone in mice can result in prostatic enlargement and recapitulate several clinical components of lower urinary tract symptoms.

Mechanosensing of shear by leads to increased levels of the cyclic-di-GMP signal initiating biofilm development.

Biofilms are communities of sessile microbes that are phenotypically distinct from their genetically identical, free-swimming counterparts. Biofilms initiate when bacteria attach to a solid surface. Attachment triggers intracellular signaling to change gene expression from the planktonic to the biofilm phenotype.

Prolactin Receptor-Mediated Internalization of Imaging Agents Detects Epithelial Ovarian Cancer with Enhanced Sensitivity and Specificity.

Poor prognosis of ovarian cancer, the deadliest of the gynecologic malignancies, reflects major limitations associated with detection and diagnosis. Current methods lack high sensitivity to detect small tumors and high specificity to distinguish malignant from benign tissue, both impeding diagnosis of early and metastatic cancer stages and leading to costly and invasive surgeries. Tissue microarray analysis revealed that >98% of ovarian cancers express the prolactin receptor (PRLR), forming the basis of a new molecular imaging strategy.

Manganese-enhanced MRI detection of impaired calcium regulation in a mouse model of cardiac hypertrophy.

The aim of this study was to use manganese (Mn)-enhanced MRI (MEMRI) to detect changes in calcium handling associated with cardiac hypertrophy in a mouse model, and to determine whether the impact of creatine kinase ablation is detectable using this method. Male C57BL/6 (C57, n = 11) and male creatine kinase double-knockout (CK-M/Mito(-/-) , DBKO, n = 12) mice were imaged using the saturation recovery Look-Locker T1 mapping sequence before and after the development of cardiac hypertrophy. Hypertrophy was induced via subcutaneous continuous 3-day infusion of isoproterenol, and sham mice not subjected to cardiac hypertrophy were also imaged.

In vivo biodistribution and clearance of peptide amphiphile micelles.

Unlabelled: Peptide amphiphiles (PAs) are promising biomaterials for medical applications. To translate the use of PAs successfully from laboratories to clinics, in vivo studies regarding the safety of these nanomaterials are required. To examine the toxicity and clearance of PA biomaterials, we intravenously administered cy7-labeled, spherical PA micelles, control micelles without a peptide sequence, or PBS in a murine model and investigated biocompatibility, biodistribution, and clearance.

High resolution 3D MRI of mouse mammary glands with intra-ductal injection of contrast media.

The purpose of this study was to use high resolution three-dimensional (3D) magnetic resonance imaging (MRI) to study mouse mammary gland ductal architecture based on intra-ductal injection of contrast agents. Female FVB/N mice age 12-20 weeks (n=12), were used in this study. A 34G, 45° tip Hamilton needle with a 25μL Hamilton syringe was inserted into the tip of the nipple.

Genetic background influences adaptation to cardiac hypertrophy and Ca(2+) handling gene expression.

Genetic variability has a profound effect on the development of cardiac hypertrophy in response to stress. Consequently, using a variety of inbred mouse strains with known genetic profiles may be powerful models for studying the response to cardiovascular stress. To explore this approach we looked at male C57BL/6J and 129/SvJ mice.

Curcumin aggravates CNS pathology in experimental systemic lupus erythematosus.

Complement activation and inflammation are key disease features of systemic lupus erythematosus. Curcumin is an anti-inflammatory agent that inhibits the complement cascade. Therefore, we hypothesized that curcumin will be protective in CNS lupus.

Empirical mathematical model for dynamic manganese-enhanced MRI of the murine pancreas for assessment of β-cell function.

Autoimmune ablation of pancreatic β-cells and alteration of its microvasculature may be a predictor of Type I diabetes development. A dynamic manganese-enhanced MRI (MEMRI) approach and an empirical mathematical model were developed to monitor whole pancreatic β-cell function and vasculature modifications in mice. Normal and streptozotocin-induced diabetic FVB/N mice were imaged on a 9.

If the skull fits: magnetic resonance imaging and microcomputed tomography for combined analysis of brain and skull phenotypes in the mouse.

The mammalian brain and skull develop concurrently in a coordinated manner, consistently producing a brain and skull that fit tightly together. It is common that abnormalities in one are associated with related abnormalities in the other. However, this is not always the case.

Functional MRI characterization of isolated human islet activation.

The noninvasive assessment of pancreatic islets would be an invaluable tool in advancing the treatment of type I diabetes and in understanding its pathophysiology. As shown previously in rodents, manganese-enhanced MRI (MEMRI) can be successfully used to quantify β-cell function. In this study, we successfully applied this technique to isolated human pancreatic islets in both a static and, more significantly, MRI-compatible perfusion set-up.

Biocompatibility of nanoporous alumina membranes for immunoisolation.

Cellular immunoisolation using semi-permeable barriers has been investigated over the past several decades as a promising treatment approach for diseases such as Parkinson's, Alzheimer's, and Type 1 diabetes. Typically, polymeric membranes are used for immunoisolation applications; however, recent advances in technology have led to the development of more robust membranes that are able to more completely meet the requirements for a successful immunoisolation device, including well controlled pore size, chemical and mechanical stability, nonbiodegradability, and biocompatibility with both the graft tissue as well as the host. It has been shown previously that nanoporous alumina biocapsules can act effectively as immunoisolation devices, and support the viability and functionality of encapsulated beta cells.

Comparison and evaluation of mouse cardiac MRI acquired with open birdcage, single loop surface and volume birdcage coils.

Although the quality and speed of MR images have vastly improved with the development of novel RF coil technologies, the engineering expertise required to implement them is often not available in many animal in vivo MR laboratories. We present here an open birdcage coil design which is easily constructed with basic RF coil expertise and produces high quality images. The quality and advantages of mouse cardiac MR images acquired with open birdcage coils were evaluated and compared to images acquired with a bent single loop surface, and standard birdcage coils acquired at 4.

Functional MR microimaging of pancreatic beta-cell activation.

The increasing incidence of diabetes and the need to further understand its cellular basis has resulted in the development of new diagnostic and therapeutic techniques. Nonetheless, the quest to noninvasively ascertain beta-cell mass and function has not been achieved. Manganese (Mn)-enhanced MRI is presented here as a tool to image beta-cell functionality in cell culture and isolated islets.

Inhibition of PKC phosphorylation of cTnI improves cardiac performance in vivo.

Protein kinase C (PKC) modulates cardiomyocyte function by phosphorylation of intracellular targets including myofilament proteins. Data generated from studies on in vitro heart preparations indicate that PKC phosphorylation of troponin I (TnI), primarily via PKC-epsilon, may slow the rates of cardiac contraction and relaxation (+dP/dt and -dP/dt). To explore this issue in vivo, we employed transgenic mice [mutant TnI (mTnI) mice] in which the major PKC phosphorylation sites on cardiac TnI were mutated by alanine substitutions for Ser(43) and Ser(45) and studied in situ hemodynamics at baseline and increased inotropy.

Phosphocreatine kinetics at the onset of contractions in skeletal muscle of MM creatine kinase knockout mice.

Phosphocreatine (PCr) depletion during isometric twitch stimulation at 5 Hz was measured by (31)P-NMR spectroscopy in gastrocnemius muscles of pentobarbital-anesthetized MM creatine kinase knockout (MMKO) vs. wild-type C57B (WT) mice. PCr depletion after 2 s of stimulation, estimated from the difference between spectra gated to times 200 ms and 140 s after 2-s bursts of contractions, was 2.

alpha-Adrenergic response and myofilament activity in mouse hearts lacking PKC phosphorylation sites on cardiac TnI.

Protein kinase C (PKC)-mediated phosphorylation of cardiac myofilament (MF) proteins has been shown to depress the actomyosin interaction and may be important during heart failure. Biochemical studies indicate that phosphorylation of Ser(43) and Ser(45) of cardiac troponin I (cTnI) plays a substantial role in the PKC-mediated depression. We studied intact and detergent-extracted papillary muscles from nontransgenic (NTG) and transgenic (TG) mouse hearts that express a mutant cTnI (Ser43Ala, Ser45Ala) that lacks specific PKC-dependent phosphorylation sites.