The Effect of Right Temporal Lobe Gliomas on Left and Right Hemisphere Neural Processing During Speech Perception and Production Tasks.

Using fMRI, we investigated how right temporal lobe gliomas affecting the posterior superior temporal sulcus alter neural processing observed during speech perception and production tasks. Behavioural language testing showed that three pre-operative neurosurgical patients with grade 2, grade 3 or grade 4 tumours had the same pattern of mild language impairment in the domains of object naming and written word comprehension. When matching heard words for semantic relatedness (a speech perception task), these patients showed under-activation in the tumour infiltrated right superior temporal lobe compared to 61 neurotypical participants and 16 patients with tumours that preserved the right postero-superior temporal lobe, with enhanced activation within the (tumour-free) contralateral left superior temporal lobe. In contrast, when correctly naming objects (a speech production task), the patients with right postero-superior temporal lobe tumours showed higher activation than both control groups in the same right postero-superior temporal lobe region that was under-activated during auditory semantic matching. The task dependent pattern of under-activation during the auditory speech task and over-activation during object naming was also observed in eight stroke patients with right hemisphere infarcts that affected the right postero-superior temporal lobe compared to eight stroke patients with right hemisphere infarcts that spared it. These task-specific and site-specific cross-pathology effects highlight the importance of the right temporal lobe for language processing and motivate further study of how right temporal lobe tumours affect language performance and neural reorganisation. These findings may have important implications for surgical management of these patients, as knowledge of the regions showing functional reorganisation may help to avoid their inadvertent damage during neurosurgery.

A Data-Based Approach for Selecting Pre- and Intra-Operative Language Mapping Tasks.

Background: Pre- and intra-operative language mapping in neurosurgery patients frequently involves an object naming task. The choice of the optimal object naming paradigm remains challenging due to lack of normative data and standardization in mapping practices. The aim of this study was to identify object naming paradigms that robustly and consistently activate classical language regions and could therefore be used to improve the sensitivity of language mapping in brain tumor and epilepsy patients. Methods: Functional magnetic resonance imaging (fMRI) data from two independent groups of healthy controls (total = 79) were used to generate threshold-weighted voxel-based consistency maps. This novel approach allowed us to compare inter-subject consistency of activation for naming single objects in the visual and auditory modality and naming two objects in a phrase or a sentence. Results: We found that the consistency of activation in language regions was greater for naming two objects per picture than one object per picture, even when controlling for the number of names produced in 5 s. Conclusion: More consistent activation in language areas for naming two objects compared to one object suggests that two-object naming tasks may be more suitable for delimiting language eloquent regions with pre- and intra-operative language testing. More broadly, we propose that the functional specificity of brain mapping paradigms for a whole range of different linguistic and non-linguistic functions could be enhanced by referring to databased models of inter-subject consistency and variability in typical and atypical brain responses.

Specifiable biomimetic microsponges for timed release of crystal entrapped biomolecules useful in bone repair.

Most marine materials, by nature, contain crystals of inorganic matter with specific structures that allow the loading, release, and delivery of biomolecules that can be utilized in clinical applications. These structures can be biomimetically synthesized. Aggregates of inorganic particles generated by biomimetic microsponges may provide surfaces and structures for cell attachment, organization, and promotion of matrix synthesis. Biomimetic microsponges have been developed with tunable release profiles differing by the rate (speed over distance), velocity (rate of change in direction), and the quantity discharged over time, according to biomolecular species. Specifically, the types of proteins involved guide and regulate cells in physical contact with the microsponges, for instance, reprogramming somatic cells, the switching phenotypes, or specifying stem cell differentiation. Applications for these microsponges include gene transfection of localized cells and promotion of bone matrix synthesis by the externalized display of RGD cell adhesive peptides and the release of crystal entrapped, occluded, adsorbed and infused rhBMP-2 and plasmid. A requirement for de novo bone formation is a solid structure to enable osteocytes to lay new bone tissue. In this study, biomimetic microsponges highlight tremendous potential as osteoconductive packing material in bone repair with parallel influence on regeneration. Majorly, microsponges offer pronounced osteoinductivity, unlike many other bone particulates, by solid-state integration of active regenerative biological molecules through the prism of the biomineral crystalline structure.

Intraoperative Optimization of Both Depth of Anesthesia and Cerebral Oxygenation in Elderly Patients Undergoing Coronary Artery Bypass Graft Surgery-A Randomized Controlled Pilot Trial.

OBJECTIVES: Does intraoperative optimization of both depth of anesthesia and regional cerebral tissue oxygenation (rScO2) in elderly patients reduce postoperative cognitive decline (primary outcome) or delirium (secondary outcome)? DESIGN: Prospective randomized controlled single blind trial. SETTING: A single major urban teaching and university hospital and tertiary referral center. PARTICIPANTS: Patients, 65 years of age and older, undergoing elective coronary artery bypass graft surgery on cardiopulmonary bypass. INTERVENTIONS: Intraoperative depth of anesthesia bispectral index (BIS) values were targeted at 50 ± 10. Regional cerebral tissue desaturations of more than 15% of the pre-induction value, or below 50%, were avoided. MEASUREMENTS AND MAIN RESULTS: Eighty-two patients were included, and mean depth of anesthesia values using BIS were significantly higher during surgery in the intervention group with 40.6 (7.3) versus 35.4 (6.7) in the control group, mean (standard deviation), p = 0.004. The cognitive function was similar between the treatment and control groups at 6 weeks postoperatively with a Mini Mental State Examination (MMSE) of 27 (26,29) in the intervention group and an MMSE of 29 (27,29) in the control group, median (interquartile range), with p = 0.12. The authors observed a reduction in the incidence of delirium, occurring in 2.4% (n = 1) of patients in the intervention group and in 20% (n = 8) in the control group (p = 0.01). CONCLUSIONS: This pilot trial demonstrates that noninvasive target-controlled depth of anesthesia monitoring is feasible. Cognitive function at 6 weeks showed no difference between the treatment and control groups; however, postoperative delirium was reduced in the intervention group.

Use of Tethered Hydrogel Microcoatings for Mesenchymal Stem Cell Equilibrium, Differentiation, and Self-Organization into Microtissues.

Therapeutic adult mesenchymal stem cells (MSCs) lose multipotency and multilineage specialization in culture and after transplantation due to the absence of complex biological architecture. Here, it is shown that a transient ultrathin covering of permeable biomaterial can be differentially formulated to either preserve multipotency or induce multidifferentiation. Accordingly, populations of single, spherical MSCs in suspended media with high selectivity and specificity can be coated. Assembly of single, double, and triple hydrogel layers at MSC membranes is initiated by first attaching MSC-specific immunoglobulins onto CD90 or Stro-1 receptors and UEA-1 and soybean lectins. A secondary biotinylated immunoglobulin is targeted for avidin binding, which becomes an attractor for biotinylated alginate or hyaluronate, which are subsequently stiffened and gelled, in situ around the entire cell surface. Alginate microcoatings permeated with mobile BMP-2-induced osteospecialized tissue, vascular endothelial growth factor (VEGF) induced microcapillary formation, while microcoatings, with selected basement membrane proteins, preserve the multipotent phenotype of MSCs, for continuing rounds of culture and directed specialization. Furthermore, forced packing of microcoated MSC populations creates prototypical tissue compartments: the coating partially simulating the extracellular matrix structures. Remarkably, microcoated MSC clusters show a tremendous simulation of a common embryological tissue transformation into the epithelium. Thus, confinement of free morphology exerts another control on tissue specialization and formation.

A First Step in De Novo Synthesis of a Living Pulp Tissue Replacement Using Dental Pulp MSCs and Tissue Growth Factors, Encapsulated within a Bioinspired Alginate Hydrogel.

INTRODUCTION: A living, self-supporting pulp tissue replacement in vitro and for transplantation is an attractive yet unmet bioengineering challenge. Our aim is to create 3-dimensional alginate-based microenvironments that replicate the shape of gutta-percha and comprise key elements for the proliferation of progenitor cells and the release of growth factors. METHODS: An RGD-bearing alginate framework was used to encapsulate dental pulp stem cells and human umbilical vein endothelial cells in a ratio of 1:1. The alginate hydrogel also retained and delivered 2 key growth factors, vascular endothelial growth factor-121 and fibroblast growth factor, in a sufficient amount to induce proliferation. A method was then devised to replicate the shape of gutta-percha using RGD alginate within a custom-made mold of thermoresponsive N-isopropylacrylamide. Plugs of alginate containing different permutations of growth factor-based encapsulates were tested and evaluated for viability, proliferation, and release kinetics between 1 and 14 days. RESULTS: According to scanning electron microscopic and confocal microscopic observations, the encapsulated human endothelial cells and dental pulp stem cell distribution were frequent and extensive throughout the length of the construct. There were also high levels of viability in all test environments. Furthermore, cell proliferation was higher in the growth factor-based groups. Growth factor release kinetics also showed significant differences between them. Interestingly, the combination of vascular endothelial growth factor and fibroblast growth factor synergize to significantly up-regulate cell proliferation. CONCLUSIONS: RGD-alginate scaffolds can be fabricated into shapes to fill the pulp space by simple templating. The addition of dual growth factors to cocultures of stem cells within RGD-alginate scaffolds led to the creation of microenvironments that significantly enhance the proliferation of dental pulp stem cell/human umbilical vein endothelial cell combinations.

Spontaneous gene transfection of human bone cells using 3D mineralized alginate-chitosan macrocapsules.

The effectiveness of nonviral gene therapy remains uncertain because of low transfection efficiencies and high toxicities compared with viral-based strategies. We describe a simple system for transient transfection of continuous human cell lines, with low toxicity, using mineral-coated chitosan and alginate capsules. As proof-of-concept, we demonstrate transfection of Saos-2 and MG63 human osteosarcoma continuous cell lines with gfp, LacZ reporter genes, and a Sox-9 carrying plasmid, to illustrate expression of a functional gene with therapeutic relevance. We show that continuous cell lines transfect with significant efficiency of up to 65% possibly through the interplay between chitosan and DNA complexation and calcium/phosphate-induced translocation into cells entrapped within the 3D polysaccharide based environment, as evidenced by an absence of transfection in unmineralized and chitosan-free capsules. We demonstrated that our transfection system was equally effective at transfection of primary human bone marrow stromal cells. To illustrate, the Sox-9, DNA plasmid was spontaneously expressed in primary human bone marrow stromal cells at 7 days with up to 90% efficiency in two repeats. Mineralized polysaccharide macrocapsules are gene delivery vehicles with a number of biological and practical advantages. They are highly efficient at self-transfecting primary bone cells, with programmable spatial and temporal delivery prospects, premineralized bone-like environments, and have no cytotoxic effects, as compared with many other nonviral systems.

Osteogenic potency of nacre on human mesenchymal stem cells.

Nacre seashell is a natural osteoinductive biomaterial with strong effects on osteoprogenitors, osteoblasts, and osteoclasts during bone tissue formation and morphogenesis. Although nacre has shown, in one study, to induce bridging of new bone across large non-union bone defects in 8 individual human patients, there have been no succeeding human surgical studies to confirm this outstanding potency. But the molecular mechanisms associated with nacre osteoinduction and the influence on bone marrow-derived mesenchymal stem cells (BMSC's), skeletal stem cells or bone marrow stromal cells remain elusive. In this study we highlight the phenotypic and biochemical effects of Pinctada maxima nacre chips and the global nacre soluble protein matrix (SPM) on primary human bone marrow-derived stromal cells (hBMSCs) in vitro. In static co-culture with nacre chips, the hBMSCs secreted Alkaline phosphatase (ALP) at levels that exceeded bone morphogenetic protein (rhBMP-2) treatment. Concentrated preparation of SPM applied to Stro-1 selected hBMSC's led to rapid ALP secretions, at concentrations exceeding the untreated controls even in osteogenic conditions. Within 21 days the same population of Stro-1 selected hBMSCs proliferated and secreted collagens I-IV, indicating the premature onset of an osteoblast phenotype. The same SPM was found to promote unselected hBMSC differentiation with osteocalcin detected at 7 days, and proliferation increased at 7 days in a dose-dependent manner. In conclusion, nacre particles and nacre SPM induced the early stages of human bone cell differentiation, indicating that they may be promising soluble factors with osteoinductive capacity in primary human bone cell progenitors such as, hBMSC's.

Clarification of the circulatory patho-physiology of anaesthesia - implications for high-risk surgical patients.

The paper examines the effects of anaesthesia on circulatory physiology and their implications regarding improvement in perioperative anaesthetic management. Changes to current anaesthetic practice, recommended recently, such as the use of flow monitoring in high risk patients, are already beginning to have an impact in reducing complications but not mortality [1]. Better understanding of the patho-physiology should help improve management even further. Analysis of selected individual clinical trials has been used to illustrate particular areas of patho-physiology and how changes in practice have improved outcome. There is physiological support for the importance of achieving an appropriate rate of oxygen delivery (DO2), particularly following induction of anaesthesia. It is suggested that ensuring adequate DO2 during anaesthesia will avoid development of oxygen debt and hence obviate the need to induce a high, compensatory, DO2 in the post-operative period. In contrast to the usual assumptions underlying strategies requiring a global increase in blood flow [1] by a stroke volume near maximization strategy, blood flow control actually resides entirely at the tissues not at the heart. This is important as the starting point for understanding failed circulatory control as indicated by 'volume dependency'. Local adjustments in blood flow at each individual organ - auto-regulation - normally ensure the appropriate local rate of oxygen supply, i.e. local DO2. Inadequate blood volume leads to impairment of the regulation of blood flow, particularly in the individual tissues with least capable auto-regulatory capability. As demonstrated by many studies, inadequate blood flow first occurs in the gut, brain and kidney. The inadequate blood volume which occurs with induction of anaesthesia is not due to blood volume loss, but probably results from redistribution due to veno-dilation. The increase in venous capacity renders the existing blood volume inadequate to maintain venous return and pre-load. Blood volume shifted to the veins will, necessarily, also reduce the arterial volume. As a result stroke volume and cardiac output fall below normal with little or no change in peripheral resistance. The resulting pre-load dependency is often successfully treated with colloid infusion and, in some studies, 'inotropic' agents, particularly in the immediate post-operative phase. Treatment during the earliest stage of anaesthesia can avoid the build up of oxygen debt and may be supplemented by drugs which maintain or restore venous tone, such as phenylephrine; an alternative to volume expansion. Interpretation of circulatory patho-physiology during anaesthesia confirms the need to sustain appropriate oxygen delivery. It also supports reduction or even elimination of supplementary crystalloid maintenance infusion, supposedly to replace the "mythical" third space loss. As a rational evidence base for future research it should allow for further improvements in anaesthetic management.

Linear poly(ethylenimine) cross-linked by methyl-ß-cyclodextrin for gene delivery.

Poly(ethylenimine) (PEI) is a cationic polymer extensively exploited for non-viral gene delivery; however, its wide application has been impeded by its cytotoxicity. PEI can assume either a branched or linear configuration. Whereas branched PEI (bPEI) is more chemically reactive and can form smaller complexes with DNA under salt-containing conditions, lPEI is generally less toxic and exhibits higher transfection efficiency. In this study, we cross-linked low-molecularweight lPEI with methyl ß-cyclodextrin (MßCD) to form MßCD-lPEI (MLP). The structure of MLP was successfully characterized by NMR, FT-IR, MALDI-TOF and elemental analysis. In the standard serum-free transfection environment, MLP could effectively transfect glioblastoma, melanoma and hepatocarcinoma cells. A high transfection efficiency was maintained in the presence of serum. Apart from its high transfection efficiency, MLP was found to have negligible cytotoxicity over a wide range of concentrations and to exhibit a low membrane disruptive capacity ex vivo. MLP warrants further development as a promising gene delivery system for future research.

New biomimetic directions in regenerative ophthalmology.

One of the most complete and permanent ways of treating many causes of visual impairment and blindness is to replace the entire affected tissue with pre-cultured ocular tissues supported and maintained on biomaterial frameworks. One direction towards enhancing ocular tissue regeneration on biomaterials, in the laboratory is by applying biomimicry. Specifically to engineer biomaterials with important functional elements of the native extracellular matrices, such as topography, that support and organise cells into coherent tissues. Further problems in regenerative ophthalmology can be potentially solved through application of biomimicry. They include, more efficient ways of moving and transplanting cultivated tissues into correct therapeutic locations inside the eye and scar-less, non-destructive healing of surgical incisions and wounds, to repair structural integrity of tissues at the ocular surface. Two examples are given to show this potential for redeveloping an ocular epithelium onto a nanostructured insect wing surface and producing an origami membrane modelled on deployable structures in nature. Efforts to harness natural innovation will eventually provide unique designs and structures that cannot for now be made synthetically, for regeneration of clinically acceptable ocular tissues.

Augmentation of skeletal tissue formation in impaction bone grafting using vaterite microsphere biocomposites.

The development of particulate bone void fillers with added biological function to augment skeletal tissue formation will lead to improved efficacy in bone replacement surgery. We demonstrate the potential for vaterite microsphere biocomposites to augment bone matrix formation within an in vivo model for impaction bone grafting seeded with human bone marrow stromal cells. In vitro tests demonstrate the significance of vaterite microspheres in the activation and promotion of 3D skeletal tissue formation. Further in vitro experiments using functionalized microspheres with surface integrated RGD peptide activate co-cultured skeletal populations in pellets and promote secretion of extracellular matrix collagens and human osteocalcin. Specific temporal release of entrapped RNase A was successfully demonstrated using these specialized microspheres with integrated magnetic beads, which physically disrupted the inorganic macrostructure. These studies demonstrate that bio-inspired calcium carbonate microspheres augment in vivo bone formation in impaction bone grafting. Such microspheres with added biological functionality offer innovative therapeutic approaches to activate skeletal populations and enhance bone formation with reparative implications for hard tissues.

Genetic manipulation of human mesenchymal progenitors to promote chondrogenesis using "bead-in-bead" polysaccharide capsules.

Articular cartilage defects arising from trauma or degenerative diseases fail to repair spontaneously. We have adopted a non-viral gene delivery and tissue engineering strategy, in which Sox-9 transfected human mesenchymal progenitors have been encapsulated within alginate/chitosan polysaccharide capsules to promote chondrogenesis. Human bone marrow stromal cells and articular chondrocytes were transfected with flag-tagged Sox-9 plasmid and after 7 days in static culture, large regions of cell-generated matrix containing cartilage proteoglycans were observed as confirmed by positive Alcian blue staining and Sox-9 immunohistochemistry. Further, after 28 days, in vitro and in vivo, samples encapsulated with Sox-9 transfected cells demonstrated large regions of cartilaginous matrix as confirmed by positive Alcian blue staining, Sox-9 and type-II collagen immunohistochemistry, absent in samples encapsulated with untransfected cells. Extracted protein from in vivo constructs was further assessed by western blot analysis and positive expression of Sox-9 and type-II collagen was observed in Sox-9 transfected constructs which was absent in untransfected cells. Regions of cartilage-like matrix were significantly increased in Sox-9 constructs in comparison with untransfected constructs, confirming Sox-9 gene delivery enhances chondrogenesis in targeted cell populations, outlining the potential to promote cartilaginous construct formation with therapeutic implications for regeneration of human articular cartilage tissue defects.

An ex vivo model for chondrogenesis and osteogenesis.

Loss of bone and cartilage are major healthcare issues. At present, there is a paucity of therapies for effectively repairing these tissues sustainably in the long term. A tissue engineering approach using advanced functional scaffolds may provide a clinically acceptable alternative. In this study, an innovative mineralized alginate/chitosan scaffold was used to provide tailored microenvironments for driving chondrogenesis and osteogenesis from single and mixed populations of human articular chondrocytes and human bone marrow stromal cells. Polysaccharide capsules were prepared with combinations of these cell types with the addition of type I or type II collagen to augment cell-matrix interactions and promote the formation of phenotypically distinct tissues and placed in a rotating (Synthecon) bioreactor or held in static 2D culture conditions for up to 28 days. Significant cell-generated matrix synthesis was observed in human bone marrow bioreactor samples containing type I collagen after 21-28 days, with increased cell proliferation, cell activity and osteocalcin synthesis. The cell-generated matrix was immuno-positive for types I and II collagen, bone sialoprotein and type X collagen, a marker of chondrogenic hypertrophy, demonstrating the formation of a mature chondrogenic phenotype with areas of new osteoid tissue formation. We present a unique approach using alginate/collagen capsules encapsulated in chitosan to promote chondrogenic and osteogenic differentiation and extracellular matrix formation and the potential for tissue-specific differentiation. This has significant implications for skeletal regeneration and application.

Strategies to promote chondrogenesis and osteogenesis from human bone marrow cells and articular chondrocytes encapsulated in polysaccharide templates.

The aim of this study was to synthesize functional in vitro and in vivo 3-dimensional (3D) constructs using a mix of human mesenchymal populations and articular chondrocytes encapsulated in biomineralized polysaccharide templates. Single-cell-type populations or mixtures of both cell types were encapsulated in alginate/chitosan and cultured within a rotating-bioreactor, perfused bioreactor system, or static conditions for 28 days. Within single cell-type populations, type II collagen immunopositive cells were present within lacunae in rotating-bioreactor capsules, with an increased proportion of metabolically active cells compared with perfused and static constructs. Biochemical analysis indicated significantly increased ( p < 0.05) DNA and protein in rotating-bioreactor conditions compared with perfused or static. However, in coculture samples, DNA and protein was significantly increased in static cultures owing to the formation of large regions of partially mineralized osteoid. This osteoid was found only in static cultures and when the ratio of human bone marrow cells to chondrocytes was 2:1 or, to a lesser extent, 5:1 ratio capsules. Subcutaneous implantation of capsules into immunocompromised mice also showed optimal osteoid formation when the ratio was 2:1. The current studies demonstrate the pivotal role of robust 3D biomimetic microenvironments and indicate the potential to harness the interactions between different cell types to create specific tissues.

Excessive ATP hydrolysis in ischemic myocardium by mitochondrial F1F0-ATPase: effect of selective pharmacological inhibition of mitochondrial ATPase hydrolase activity.

Mitochondrial F(1)F(0)-ATPase normally synthesizes ATP in the heart, but under ischemic conditions this enzyme paradoxically causes ATP hydrolysis. Nonselective inhibitors of this enzyme (aurovertin, oligomycin) inhibit ATP synthesis in normal tissue but also inhibit ATP hydrolysis in ischemic myocardium. We characterized the profile of aurovertin and oligomycin in ischemic and nonischemic rat myocardium and compared this with the profile of BMS-199264, which only inhibits F(1)F(0)-ATP hydrolase activity. In isolated rat hearts, aurovertin (1-10 microM) and oligomycin (10 microM), at concentrations inhibiting ATPase activity, reduced ATP concentration and contractile function in the nonischemic heart but significantly reduced the rate of ATP depletion during ischemia. They also inhibited recovery of reperfusion ATP and contractile function, consistent with nonselective F(1)F(0)-ATPase inhibitory activity, which suggests that upon reperfusion, the hydrolase activity switches back to ATP synthesis. BMS-199264 inhibits F(1)F(0) hydrolase activity in submitochondrial particles with no effect on ATP synthase activity. BMS-199264 (1-10 microM) conserved ATP in rat hearts during ischemia while having no effect on preischemic contractile function or ATP concentration. Reperfusion ATP levels were replenished faster and necrosis was reduced by BMS-199264. ATP hydrolase activity ex vivo was selectively inhibited by BMS-199264. Therefore, excessive ATP hydrolysis by F(1)F(0)-ATPase contributes to the decline in cardiac energy reserve during ischemia and selective inhibition of ATP hydrolase activity can protect ischemic myocardium.

Benzodiazepine-based selective inhibitors of mitochondrial F1F0 ATP hydrolase.

A series of benzodiazepine-based inhibitors of mitochondrial F(1)F(0) ATP hydrolase were prepared and evaluated for their ability to selectively inhibit the enzyme in the forward direction. Compounds from this series showed excellent potency and selectivity for ATP hydrolase versus ATP synthase, suggesting a potentially beneficial profile useful for the treatment of ischemic heart disease.

N-[1-Aryl-2-(1-imidazolo)ethyl]-guanidine derivatives as potent inhibitors of the bovine mitochondrial F1F0 ATP hydrolase.

A series of substituted guanidine derivatives were prepared and evaluated as potent and selective inhibitors of mitochondrial F(1)F(0) ATP hydrolase. The initial thiourethane derived lead molecules possessed intriguing in vitro pharmacological profiles, though contained moieties considered non-drug-like. Analogue synthesis efforts led to compounds with maintained potency and superior physical properties. Small molecules in this series which potently and selectivity inhibit ATP hydrolase and not ATP synthase may have utility as cardioprotective agents.

Small molecule mitochondrial F1F0 ATPase hydrolase inhibitors as cardioprotective agents. Identification of 4-(N-arylimidazole)-substituted benzopyran derivatives as selective hydrolase inhibitors.

In this paper we show that 4-aryl-CH2-imidazole-substituted benzopyran compounds with 3S,4R-stereochemistry are cardioprotective by inhibiting the F1F0 mitochondrial ATP hydrolase. Compounds (e.g., 13) with 3R,4S-stereochemistry act as mitochondrial KATP openers. This resulted from an inversion of stereochemistry for the F1F0 mitochondrial ATP hydrolase vs mitochondrial KATP. Structure-activity relationships for the inhibition of mitochondrial ATP hydrolase are also delineated. It is not clear how 13 (3R,4S) can selectively inhibit the hydrolytic activity of the F1F0 mitochondrial enzyme without interfering with the synthase activity.