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Rationale: Sorafenib is an effective treatment for renal cell carcinoma, but recent clinical reports have documented its cardiotoxicity through an unknown mechanism., Objective: Determining the mechanism of sorafenib-mediated cardiotoxicity., Methods and Results: Mice treated with sorafenib or vehicle for 3 weeks underwent induced myocardial infarction (MI) after 1 week of treatment. Sorafenib markedly decreased 2-week survival relative to vehicle-treated controls, but echocardiography at 1 and 2 weeks post MI detected no differences in cardiac function. Sorafenib-treated hearts had significantly smaller diastolic and systolic volumes and reduced heart weights. High doses of sorafenib induced necrotic death of isolated myocytes in vitro, but lower doses did not induce myocyte death or affect inotropy. Histological analysis documented increased myocyte cross-sectional area despite smaller heart sizes after sorafenib treatment, further suggesting myocyte loss. Sorafenib caused apoptotic cell death of cardiac- and bone-derived c-kit+ stem cells in vitro and decreased the number of BrdU+ (5-bromo-2'-deoxyuridine+) myocytes detected at the infarct border zone in fixed tissues. Sorafenib had no effect on infarct size, fibrosis, or post-MI neovascularization. When sorafenib-treated animals received metoprolol treatment post MI, the sorafenib-induced increase in post-MI mortality was eliminated, cardiac function was improved, and myocyte loss was ameliorated., Conclusions: Sorafenib cardiotoxicity results from myocyte necrosis rather than from any direct effect on myocyte function. Surviving myocytes undergo pathological hypertrophy. Inhibition of c-kit+ stem cell proliferation by inducing apoptosis exacerbates damage by decreasing endogenous cardiac repair. In the setting of MI, which also causes large-scale cell loss, sorafenib cardiotoxicity dramatically increases mortality., (© 2014 American Heart Association, Inc.)

The etiology of polycystic ovary syndrome (PCOS) has been difficult to determine because its features are heterogeneous, and its origin may also be heterogeneous. Twin studies suggest that its etiology is strongly heritable and genetic approaches are rapidly uncovering new regions of the genome that appear to confer risk for PCOS. Recent genome-wide association studies in Han Chinese women with PCOS demonstrate 11 genetic loci that are associated with PCOS. The variants identified are in regions that contain genes important for gonadotropin action, genes that are associated with risk for type 2 diabetes, and other genes in which the relationship to PCOS is not yet clear. Replication studies have demonstrated that variants at several of these loci also confer risk for PCOS in women of European ethnicity. The strongest loci in Europeans contain genes for DENND1A and THADA, with additional associations in loci containing the LHCGR and FSHR, YAP1 and RAB5/SUOX. The next steps in uncovering the pathophysiology borne out by these loci and variants will include mapping to determine the causal variant and gene, phenotype studies to determine whether these regions are associated with particular features of PCOS and functional studies of the causal variant to determine the direct cause of PCOS based on the underlying genetics. The next years will be very exciting times as groups from around the world come together to further elucidate the genetic origins of PCOS., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Energy transfer between a macromolecule or supramolecular assembly and a host medium is considered from the perspective of Newton's equations and Lie-Trotter factorization. The development starts by demonstrating that the energy of the molecule evolves slowly relative to the time scale of atomic collisions-vibrations. The energy is envisioned to be a coarse-grained variable that coevolves with the rapidly fluctuating atomistic degrees of freedom. Lie-Trotter factorization is shown to be a natural framework for expressing this coevolution. A mathematical formalism and workflow for efficient multiscale simulation of energy transfer is presented. Lactoferrin and human papilloma virus capsid-like structure are used for validation.

We present a case of drug-induced QT prolongation caused by an escitalopram overdose in a patient with previously undiagnosed congenital LQTS. A 15-year-old Caucasian female presented following a suicide attempt via an escitalopram overdose. The patient was found to have a prolonged QT interval with episodes of torsades de pointes. The patient was admitted to the telemetry unit and treated. Despite the resolution of the torsades de pointes, she continued to demonstrate a persistently prolonged QT interval. She was seen by the cardiology service and diagnosed with congenital long QT syndrome. This case illustrates the potential for an escitalopram overdose to cause an acute QT prolongation in a patient with congenital LQTS and suggests the importance of a screening electrocardiogram prior to the initiation of SSRIs, especially in patients at high risk for QT prolongation.

Rationale: Autologous bone marrow-derived or cardiac-derived stem cell therapy for heart disease has demonstrated safety and efficacy in clinical trials, but functional improvements have been limited. Finding the optimal stem cell type best suited for cardiac regeneration is the key toward improving clinical outcomes., Objective: To determine the mechanism by which novel bone-derived stem cells support the injured heart., Methods and Results: Cortical bone-derived stem cells (CBSCs) and cardiac-derived stem cells were isolated from enhanced green fluorescent protein (EGFP+) transgenic mice and were shown to express c-kit and Sca-1 as well as 8 paracrine factors involved in cardioprotection, angiogenesis, and stem cell function. Wild-type C57BL/6 mice underwent sham operation (n=21) or myocardial infarction with injection of CBSCs (n=67), cardiac-derived stem cells (n=36), or saline (n=60). Cardiac function was monitored using echocardiography. Only 2/8 paracrine factors were detected in EGFP+ CBSCs in vivo (basic fibroblast growth factor and vascular endothelial growth factor), and this expression was associated with increased neovascularization of the infarct border zone. CBSC therapy improved survival, cardiac function, regional strain, attenuated remodeling, and decreased infarct size relative to cardiac-derived stem cells- or saline-treated myocardial infarction controls. By 6 weeks, EGFP+ cardiomyocytes, vascular smooth muscle, and endothelial cells could be identified in CBSC-treated, but not in cardiac-derived stem cells-treated, animals. EGFP+ CBSC-derived isolated myocytes were smaller and more frequently mononucleated, but were functionally indistinguishable from EGFP- myocytes., Conclusions: CBSCs improve survival, cardiac function, and attenuate remodeling through the following 2 mechanisms: (1) secretion of proangiogenic factors that stimulate endogenous neovascularization, and (2) differentiation into functional adult myocytes and vascular cells.

Some memories enter into a labile state after retrieval, requiring reconsolidation in order to persist. One functional role of memory reconsolidation is the updating of existing memories. There are reports suggesting that reconsolidation can be modulated by a particular endogenous process taking place concomitantly to its natural course, such as water or sleep deprivation. Here, we investigated whether an endogenous process activated during a natural/physiological experience, or a pharmacological intervention, can also contribute to memory content updating. Using the contextual fear conditioning paradigm in rats, we found that the endogenous content of an aversive memory can be updated during its reconsolidation incorporating consequences of natural events such as water deprivation, transforming a previously stored memory into a state-dependent one. This updating seems to be mediated by the activation of angiotensin AT1 receptors in the dorsal hippocampus and local infusion of human angiotensin II (ANGII) was shown to mimic the water deprivation effects on memory reconsolidation. Systemic morphine injection was also able to turn a previously acquired experience into a state-dependent memory, reproducing the very same effects obtained by water deprivation or local angiotensin II infusion, and suggesting that other state-dependent-inducing protocols would also be able to contribute to memory updating. These findings trigger new insights about the influence of ordinary daily life events upon memory in its continuing reconstruction, adding the realm of reconsolidation to the classical view of endogenous modulation of consolidation.

Background: Prehospital intubation does not result in a survival advantage in patients experiencing penetrating trauma, yet resistance to immediate transportation to facilitate access to definitive care remains. An animal model was developed to determine whether intubation provides a survival advantage during severe hemorrhagic shock. We hypothesized that intubation would not provide a survival advantage in potentially lethal hemorrhage., Methods: After starting a propofol drip, Yorkshire pigs were intubated (n = 6) or given bag-valve mask ventilation (n = 7) using 100% oxygen. The carotid artery was cannulated with a 14-gauge catheter, and a Swan-Ganz catheter was placed under fluoroscopy using a central venous introducer. After obtaining baseline hemodynamic and laboratory data, the animals were exsanguinated through the carotid line until death. The primary end point was time until death, while secondary end points included volume of blood shed, temperature, cardiac index, mean arterial pressure, lactic acid, base excess, and creatinine levels measured in 10-minute intervals., Results: There was no difference in time until death between the two groups (51.1 [2.5] minutes vs. 48.5 [2.4] minutes, p = 0.52). Intubated animals had greater volume of blood shed at 30 minutes (33.6 [4.4] mL/kg vs. 28.5 [4.3] mL/kg, p = 0.03), 40 minutes (41.7 [4.7] mL/kg vs. 34.9 [3.8] mL/kg, p = 0.04), and 50 minutes (49.2 [8.6] mL/kg vs. 40.2 [1.0] mL/kg, p = 0.001). In addition, the intubated animals were more hypothermic at 40 minutes (35.5°C [0.4°C] vs. 36.7°C [0.2°C], p = 0.01) and had higher lactate levels (2.4 [0.1] mmol/L vs. 1.8 [0.4] mmol/L, p = 0.04) at 10 minutes. Cardiac index (p = 0.66), mean arterial pressure (p = 0.69), base excess (p = 0.14), and creatinine levels (p = 0.37) were not different throughout the shock phase., Conclusion: Intubation does not convey a survival advantage in this model of severe hemorrhagic shock. Furthermore, intubation in the setting of severe hemorrhagic shock may result in a more profuse hemorrhage, worse hypothermia, and higher lactate when compared with bag-valve mask ventilation.

Sphingomyelin and cholesterol can assemble into domains and segregate from other lipids in the membranes. These domains are reported to function as platforms for protein transport and signalling. Do similar domains exist in the Golgi membranes and are they required for protein secretion? We tested this hypothesis by using D-ceramide-C6 to manipulate lipid homeostasis of the Golgi membranes. Lipidomics of the Golgi membranes isolated from D-ceramide-C6-treated HeLa cells revealed an increase in the levels of C6-sphingomyelin, C6-glucosylceramide, and diacylglycerol. D-ceramide-C6 treatment in HeLa cells inhibited transport carrier formation at the Golgi membranes without affecting the fusion of incoming carriers. The defect in protein secretion as a result of D-ceramide-C6 treatment was alleviated by knockdown of the sphingomyelin synthases 1 and 2. C6-sphingomyelin prevented liquid-ordered domain formation in giant unilamellar vesicles and reduced the lipid order in the Golgi membranes of HeLa cells. These findings highlight the importance of a regulated production and organization of sphingomyelin in the biogenesis of transport carriers at the Golgi membranes.

Multiple clinical trials have been conducted to determine the outcome of stem cell transplantation on cardiac function. However, marked variability in design across these trials has generated ambiguity in interpretation of their results. This review systematically evaluates the currently available protocols to illustrate the need for a standardized protocol for future trials., (Copyright © 2012 Mosby, Inc. All rights reserved.)

Introduction: Novel therapies for myocardial infarction (MI) involving stem cells, gene therapy, biomaterials, or revascularization strategies have shown promise in animal studies and clinical trials, but results have been limited partially due to the injection of therapeutics into ischemic myocardium that cannot support their mechanism of action. Accurate targeting of therapeutics precisely to the infarct border zone (BZ) may be essential for effective repair of the ischemic heart., Methods: Ischemia-reperfusion MI was induced in Yorkshire swine by inflation of an angioplasty balloon in the left anterior descending coronary artery. Fluorescent microspheres were injected into the BZ under NOGA catheter guidance, and this location was identified grossly then examined by immunohistochemistry and Western analysis., Results: Analysis of the infarct zone two hours post-MI revealed a frankly necrotic region devoid of contractile proteins with marked activation of caspase-3. The NOGA-defined BZ closely approximates the grossly-defined BZ and contains intact myocytes and vasculature. Western analysis detected Akt expression and levels of Ca(2+) handling proteins equivalent to that of viable tissues., Conclusions: Histological and Western analysis revealed that NOGA mapping precisely identifies grossly and molecularly defined infarct BZ at a location where there are still viable cells and vessels capable of supporting novel therapeutic strategies., (© 2012 Wiley Periodicals, Inc.)

Background: Prehospital intubation does not appear to result in a survival advantage for patients experiencing penetrating trauma; yet, there is still resistance to the practice of "scoop and run" to speed access to advanced care. An animal model was used to determine whether intubation provides a survival advantage during potentially lethal hemorrhage., Methods: The carotid arteries of Sprague-Dawley rats were cannulated, and mean arterial pressure (MAP) was measured. One group of animals (n = 10) was intubated and placed on a ventilator, whereas the other (n = 9) was administered with 100% oxygen via nose cone. Rats were exsanguinated to a MAP of 40 mm Hg and then bled periodically to maintain a MAP between 40 mm Hg and 45 mm Hg. The primary end-point was time until death. Secondary end-points included lactic acid and base excess levels measured in blood collected at 30-minute intervals after inducing shock., Results: There was no significant difference in time until death between the intubated and nose cone groups (85.5 vs. 93.3 minutes, p = 0.60). Intubated animals had higher lactic acid levels at 90 minutes (6.1 vs. 3.5 mmol/L; p = 0.02) and 120 minutes (7.7 vs. 2.6 mmol/L, p = 0.03) after the initiation of shock. In addition, intubated animals had worse base excess at 90 minutes (-13.5 vs. -7.9 mmol/L, p = 0.04)., Conclusion: Intubation does not result in a survival advantage in this rat model of hemorrhagic shock. Positive pressure ventilation may cause decreased venous return and accentuate end-organ hypoperfusion. Large animal studies are needed to further investigate these findings.

Background: Few data exist regarding payer status as a predictor of outcomes in penetrating trauma. This study determined whether insurance status impacts in-hospital complications and mortality in gunshot and stab wound patients at our inner-city, level I trauma center., Methods: Penetrating trauma admissions from 2005 to 2009 were reviewed for patient demographics, insurance, Injury Severity Score, complications, duration of stay, and mortality., Results: A total of 1,347 penetrating trauma patients were admitted with 652 (48.4%) uninsured. Although uninsured patients were more likely to be male (93.3% vs 89.8%, P = .030), there was no difference in age, ISS, or number of radiologic, operative, or interventional procedures. Uninsured patients had lesser intensive care unit (4.4 vs 3.3 days; P = .049) and total hospital length of stay (10.2 vs 8.3; P = .049). No uninsured patients were placed into a rehabilitation facility at the time of discharge (0.0% vs 1.6%, P < .001). There was no difference in frequency of pulmonary complications, thromboembolic complications, sepsis, urinary tract infection, or wound infections. On multivariate analysis, being uninsured was not an independent predictor of in-hospital complications (1.010, 95% confidence interval 0.703-1.450, P = .959) or mortality (odds ratio 0.905, 95% confidence interval 0.523-1.566, P = .722)., Conclusion: This is the first study to show that penetrating trauma patients who are uninsured have lesser duration of stay and decreased placement into a rehabilitation facility. Being uninsured added no additional risk of in-hospital complications or mortality., (Copyright © 2012 Mosby, Inc. All rights reserved.)

Rationale: Abnormal behavior of the cardiac ryanodine receptor (RyR2) has been linked to cardiac arrhythmias and heart failure (HF) after myocardial infarction (MI). It has been proposed that protein kinase A (PKA) hyperphosphorylation of the RyR2 at a single residue, Ser-2808, is a critical mediator of RyR dysfunction, depressed cardiac performance, and HF after MI., Objective: We used a mouse model (RyRS2808A) in which PKA hyperphosphorylation of the RyR2 at Ser-2808 is prevented to determine whether loss of PKA phosphorylation at this site averts post MI cardiac pump dysfunction., Methods and Results: MI was induced in wild-type (WT) and S2808A mice. Myocyte and cardiac function were compared in WT and S2808A animals before and after MI. The effects of the PKA activator Isoproterenol (Iso) on L-type Ca(2+) current (I(CaL)), contractions, and [Ca(2+)](I) transients were also measured. Both WT and S2808A mice had depressed pump function after MI, and there were no differences between groups. MI size was also identical in both groups. L type Ca(2+) current, contractions, Ca(2+) transients, and SR Ca(2+) load were also not significantly different in WT versus S2808A myocytes either before or after MI. Iso effects on Ca(2+) current, contraction, Ca(2+) transients, and SR Ca(2+) load were identical in WT and S2808A myocytes before and after MI at both low and high concentrations., Conclusions: These results strongly support the idea that PKA phosphorylation of RyR-S2808 is irrelevant to the development of cardiac dysfunction after MI, at least in the mice used in this study.

Ischemic heart disease, despite advances in treatment, remains the major cause of mortality worldwide. NOGA 3D left ventricular electromechanical mapping allows accurate determination of cardiac function and precise identification of sites of injury. In a porcine model of ischemia-reperfusion injury, we validate the use of the NOGA mapping system for assessment of cardiac function along with the Myostar injection catheter for directed delivery of therapeutics to localized target sites in the setting of acute myocardial injury.

The endoplasmic reticulum (ER)-Golgi-independent, unconventional secretion of Acb1 requires many different proteins. They include proteins necessary for the formation of autophagosomes, proteins necessary for the fusion of membranes with the endosomes, proteins of the multivesicular body pathway, and the cell surface target membrane SNARE Sso1, thereby raising the question of what achieves the connection between these diverse proteins and Acb1 secretion. In the present study, we now report that, upon starvation in Saccharomyces cerevisiae, Grh1 is collected into unique membrane structures near Sec13-containing ER exit sites. Phosphatidylinositol 3 phosphate, the ESCRT (endosomal sorting complex required for transport) protein Vps23, and the autophagy-related proteins Atg8 and Atg9 are recruited to these Grh1-containing membranes, which lack components of the Golgi apparatus and the endosomes, and which we call a novel compartment for unconventional protein secretion (CUPS). We describe the cellular proteins required for the biogenesis of CUPS, which we believe is the sorting station for Acb1's release from the cells.

Starving Dictyostelium discoideum cells secrete AcbA, an acyl coenzyme A-binding protein (ACBP) that lacks a conventional signal sequence for entering the endoplasmic reticulum (ER). Secretion of AcbA in D. discoideum requires the Golgi-associated protein GRASP. In this study, we report that starvation-induced secretion of Acb1, the Saccharomyces cerevisiae ACBP orthologue, also requires GRASP (Grh1). This highlights the conserved function of GRASP in unconventional secretion. Although genes required for ER to Golgi or Golgi to cell surface transport are not required for Acb1 secretion in yeast, this process involves autophagy genes and the plasma membrane t-SNARE, Sso1. Inhibiting transport to vacuoles does not affect Acb1 secretion. In sum, our experiments reveal a unique secretory pathway where autophagosomes containing Acb1 evade fusion with the vacuole to prevent cargo degradation. We propose that these autophagosome intermediates fuse with recycling endosomes instead to form multivesicular body carriers that then fuse with the plasma membrane to release cargo.

Knockdown of the actin-severing protein actin-depolymerizing factor (ADF)/cofilin inhibited export of an exogenously expressed soluble secretory protein from Golgi membranes in Drosophila melanogaster and mammalian tissue culture cells. A stable isotope labeling by amino acids in cell culture mass spectrometry-based protein profiling revealed that a large number of endogenous secretory proteins in mammalian cells were not secreted upon ADF/cofilin knockdown. Although many secretory proteins were retained, a Golgi-resident protein and a lysosomal hydrolase were aberrantly secreted upon ADF/cofilin knockdown. Overall, our findings indicate that inactivation of ADF/cofilin perturbed the sorting of a subset of both soluble and integral membrane proteins at the trans-Golgi network (TGN). We suggest that ADF/cofilin-dependent actin trimming generates a sorting domain at the TGN, which filters secretory cargo for export, and that uncontrolled growth of this domain causes missorting of proteins. This type of actin-dependent compartmentalization and filtering of secretory cargo at the TGN by ADF/cofilin could explain sorting of proteins that are destined to the cell surface.

Objective: Evaluate the clinical characteristics of feeding difficulties in 30 community (i.e., nonreferred) infants in the first 2 years of life, and their correlation with mother/child interactions., Method: An "in depth" mental health evaluation of feeding difficulties, and the psychosocial functioning of the child in other areas. The mother-infant relationship and the feeding interactions were also assessed., Results: Four "groups" were identified. (1) Young infant with difficulties in regulating states and sucking. (2) Older infant with difficulties in self-regulation, focusing, hyper-alert, and with aversion to feeding. (3) Older infants hypersensitive to stimuli (taste, odor) and with difficulties in chewing. (4) Group of with varied and unique feeding problems (pica, rumination)., Conclusion: Feeding problems tend to have patterns according to the age of the baby in a nonreferred sample. They are not associated with an altered parent-infant relationship nor poor feeding technique. Parents often adapt successfully to the uniqueness of the baby to maintain weight gain., ((c) 2008 by Wiley Periodicals, Inc.)

GRASP55 is a Golgi-associated protein, but its function at the Golgi remains unclear. Addition of full-length GRASP55, GRASP55-specific peptides, or an anti-GRASP55 antibody inhibited Golgi fragmentation by mitotic extracts in vitro, and entry of cells into mitosis. Phospho-peptide mapping of full-length GRASP55 revealed that threonine 225 and 249 were mitotically phosphorylated. Wild-type peptides containing T225 and T249 inhibited Golgi fragmentation and entry of cells into mitosis. Mutant peptides containing T225E and T249E, in contrast, did not affect Golgi fragmentation and entry into mitosis. These findings reveal a role of GRASP55 in events leading to Golgi fragmentation and the subsequent entry of cell into mitosis. Surprisingly, however, under our experimental conditions, >85% knockdown of GRASP55 did not affect the overall organization of Golgi organization in terms of cisternal stacking and lateral connections between stacks. Based on our findings we suggest that phosphorylation of GRASP55 at T225/T249 releases a bound component, which is phosphorylated and necessary for Golgi fragmentation. Thus, GRASP55 has no role in the organization of Golgi membranes per se, but it controls their fragmentation by regulating the release of a partner, which requires a G2-specific phosphorylation at T225/T249.

Objective: The objective of this study was to compare the initial and long-term outcome of elderly and younger patients after coronary stent implantation., Methods: The evolutions of 76 patients aged >75 years and of 860 patients aged < or =75 years who underwent consecutive stenting (from June 1991 to June 1997) were compared in a cohort study., Results: The elderly patients had lower left ventricular ejection fractions (0.58 +/- 0.14 vs 0.61 +/- 0.13; P =.03) and more frequently had unstable angina (78.9% vs 55.3%; P <.0001), previous heart failure (10.5% vs 4.9%; P =.03), and multivessel disease (68.4% vs 58.3%; P =.08). After the procedure, the elderly patients showed a higher inhospital mortality rate (6.6% vs 2.4%; P =.03) and myocardial infarction rate (5.3% vs 1.7%; P =.04). The long-term follow-up period (mean, 3.2 +/- 1.4 years; median, 3.0 years) showed in the elderly a higher mortality rate (15.4% vs 5.8%; P =.006), a lower rate of repeat revascularization (9.2% vs 19.7%; P =.04), and a similar incidence rate of major adverse cardiac events (27.7% vs 28.2%; P =.93). Multivariate analysis of the elderly group identified female gender (hazard ratio, 2.19; 95% CI, 1.18 to 4.06; P =.012) and presence of multivessel disease (hazard ratio, 2.35; 95% CI, 1.05 to 5.26; P =.037) as independent predictors of further events., Conclusion: Patients aged >75 years have a less favorable baseline profile and higher inhospital and 3-year mortality rates. However, the incidence rate of major adverse cardiac events in the long term is acceptable and similar to that of younger patients.

Neural cell adhesion molecule (NCAM) constitutes a group of cell surface glycoproteins that regulate cell-cell interactions in the developing and adult brain. Endocytosis is a mechanism which dynamically controls the amount of cell surface NCAM expression and may involve the rapid changes occurring in NCAM expression under certain physiological or pathological conditions. However, the endocytic pathway of NCAM is presently unknown. Using astrocytes in culture and immunofluorescence we show that NCAM is internalized and that the immunolabelling presents a high degree of colocalization with clathrin, alpha-adaptin and transferrin, suggesting that NCAM is endocytosed by a clathrin-dependent pathway. Potassium depletion which disrupts clathrin-mediated endocytosis, inhibited internalization of NCAM. Electron microscopy and immunogold studies also demonstrate that the surface of clathrin-coated vesicles are also immunolabelled for both alpha-adaptin and PSA-NCAM, the highly sialylated isoform of NCAM. Furthermore, immunoprecipation studies demonstrate that NCAM is associated with both clathrin and alpha-adaptin, a component of adaptor complex AP-2, in brain, neurons and astrocytes. These findings indicate that NCAM is mainly endocytosed via clathrin-coated vesicles, suggesting a possible mechanism that may contribute to the rapid changes in NCAM expression at the cell surface.

Currently, antibacterial activity is measured primarily via in vitro laboratory tests. Clinicians rely heavily upon the reported susceptibility gained via in vitro laboratory tests when choosing an antibacterial agent. An evolving concept is to utilise pharmacodynamic and pharmacokinetic drug properties in addition to in vitro susceptibility reports to assess the potential effectiveness of an antibacterial agent against a specific pathogen. This article presents examples of the utility of these concepts in terms of optimal clinical use of common antibacterials as well as more informed interpretation of the in vitro literature.

Calcium antagonists are the treatment of choice in vasospasm angina when no stenosis or mild stenosis are present. We present a case in which ergonovine echocardiography showed vasospasm of the right coronary artery despite optimal medical treatment. Stenting of a mild stenosis in that artery successfully controlled vasospasm and a pre-discharge ergonovine echocardiographic test was negative. The patient remains asymptomatic one year after stenting.

The global challenge of optimally treating bacterial infections is continuously evolving. Azithromycin, the first azalide antibiotic, presents pharmacokinetics and pharmacodynamics that allow for a simple dosing regimen with minimal side effects. Current azithromycin uses include a variety of community-acquired respiratory tract, skin and soft tissue, and sexually transmitted disease infections. Azithromycin has also demonstrated substantial activity against atypical organisms such as Mycobacterium avium complex (MAC) and Chlamydia trachomatis. Due to a never-ending need for new antibiotic therapies, several other potential indications for azithromycin are being researched. This article will present various current research associated with azithromycin's potential use for malaria, trachoma, coronary artery disease (CAD), Pseudomonas aeruginosa infections, erythema migrans, short-term therapy for respiratory infections, typhoid, cryptosporidiosis, pelvic inflammatory disease, acne, Mediterranean spotted fever and MAC. As bacterial and parasite resistance patterns fluctuate globally, azithromycin may be an alternative therapy for the previously mentioned indications, which will also enhance patient compliance and therefore effectively eradicate infection worldwide.

Background: Myocardial reperfusion is associated with calcium overload and cell contracture, mechanisms that may precipitate cell death. In this study, we tested the hypothesis that in vivo inhibition of this contracture could lead to cell preservation in an open-chest large animal model., Methods and Results: Regional myocardium function was measured during a selective intracoronary infusion of 2,3-butanedione monoxime (BDM), a specific inhibitor of actin-myosin coupling, in the control state (10 pigs) and in a protocol of a 51-minute coronary occlusion followed by reperfusion (40 pigs). The effects on coronary artery blood flow in the basal state were also studied (seven pigs). Intramyocardial distribution of the infusate during coronary occlusion, myocardial water content after 30 minutes of reperfusion and area at risk, infarct size, type of histological necrosis, and infarct geometry after 24 hours of reperfusion were assessed. Methods used included electromagnetic flowmeter, radiolabeled microspheres, subendocardial sonomicrometers, fluorescein, triphenyl tetrazolium chloride and Masson's trichrome staining, and computer quantification of infarct edges. In the absence of ischemia, BDM infusion inhibited regional shortening in a dose-dependent manner up to full systolic bulging while producing marked regional increase in coronary blood flow. During early reperfusion, BDM reduced end-diastolic length 76% more than the control infusion (p less than 0.05) and increased systolic bulging by 420% compared with no change in control animals. The ratio of infarct size/area at risk was reduced by 31% with BDM (p less than 0.05), with striking modifications of infarct histology and infarct geometry; specifically, the extent of contraction band necrosis was reduced by 63% from 105.5 +/- 18.2 to 39.2 +/- 13.6 mm2 (p less than 0.02), and more patches of necrosis (6.5 +/- 2.1 versus 1.6 +/- 0.4, p less than 0.05) and higher contour (7.7 +/- 1.2 versus 5.03 +/- 0.2, p less than 0.05) and fractal (12.1 +/- 1.3 versus 7.8 +/- 0.2, p less than 0.05) indexes were found., Conclusions: Selective intracoronary infusion of BDM at doses inhibiting regional wall motion decreased infarct size after reperfusion. The effects of BDM on regional function, the reduction in contraction band necrosis at histology, and the peculiar configuration of these infarcts all suggest that inhibition of contracture can interfere with cell-to-cell progression of myocardial necrosis, supporting a role for contracture in reperfusion-induced cell death.

Myocardial water content and infarct size were studied in 39 pigs randomly assigned to a nonintervention group, a group with an intracoronary infusion of a control solution, and a group with a hyperosmotic infusion to 450 mosM by the addition of D-mannitol. The intracoronary solutions were selectively infused into the left anterior descending coronary artery just distal to the occlusion site starting 48 min after occlusion. Reperfusion was performed 3 min later and the infusion rate progressively tapered off over the following 33 min. Multiple myocardial fragments were then obtained in nine pigs, from endocardial, mesocardial, and epicardial regions of the ischemic and control myocardium. Water content measured after 48 h of dessication was significantly greater in the reperfused [530 +/- 7 ml/100 (mean +/- SE) g dry wt] compared with control myocardium (374 +/- 3; P less than 0.0001) and similar in reperfused control and isotonic infusion groups (556 +/- 7 and 543 +/- 8 ml/100 g dry wt); it was 491 +/- 11 with intracoronary D-mannitol infusion, representing 35% less increase (P less than 0.001). In the 30 remaining pigs, area at risk and infarct size were measured 24 h later by in vivo fluorescein and in vitro triphenyltetrazolium chloride. Infarct size was similar in control and in the isotonic reperfused hearts, 6.80 +/- 1.05 and 6.22 +/- 0.76% of ventricular weight, and smaller with D-mannitol, 4.46 +/- 0.46 (P less than 0.05). The ratio of infarct size to area at risk was also smaller [0.415 +/- 0.029 vs. 0.543 +/- 0.052 and 0.547 +/- 0.045 (P less than 0.02)].(ABSTRACT TRUNCATED AT 250 WORDS)

Responsiveness of ovarian adenylyl cyclases to luteinizing hormone (LH), found to be 5 to 10-fold in cell-free preparations under optimal conditions, required gentle homogenizations and storage in sucrose-containing media. Assay conditions required the use of an ATP-regenerating system consisting of creatine kinase, creatine phosphate, and myokinase for the preservation of ATP levels. LH-stimulated adenylyl cyclase (AC) in rabbit CL showed the following properties: 1) The pH optimum of basal activity was about 8.0; that of LH-stimulated activity was about 7.5. 2) The relative response to LH was low (1.5 to 2-fold) at 0.1 mM ATP and increased with increasing ATP, but not with increasing GTP. At low (0.1 mM) ATP, GTP increased catalytic efficacy of the system, both in the absence and in the presence of LH (no effect on relative stimulation). 3) The optimal relative stimulation by LH was obtained at about 1.0 mM MgCl2 in excess of added magnesium-binding ingredients. 4) The sensitivity to stimulation by LH (about 0.2 mug/ml NIH-LH-B8) was unaffected by either pH, nucleotides (ATP and GTP), or MgCl2 concentration. 5) Under the assay conditions used, activity was stimulated by prostaglandin E1 (PGE1) about 1.5 to 2-fold, and by epinephrine about 3 to 4-fold. In all aspects tested, LH-stimulated AC in rat CL resembled that in rabbit CL, except that about 5-fold higher concentrations of NIH-LH-B8 were needed for half-maximal stimulation. The AC activity in pig Graafian follicles, however, differed from that in rabbit CL in that 1) the ATP concentration needed for optimal stimulation by LH was lower (in the micromolar rather than the millimolar range); 2) catecholamines elicited only a 1.3 to 1.4-fold stimulation; and 3) NIH-LH-B8 elicited half-maximal stimulation at 0.008 to 0.020 mug/ml. We were unable to detect LH-responsive AC activity in either homogenates or washed particles of CL from either cycling or pregnant pigs. LH fractions of three origins (human, bovine, and ovine) and of varying specific activities (from 0.041 to 2.0 NIH-LH-S18 units/mg) were tested and the relative potencies by OAAD assay were found to correlate well with the relative potencies in the adenylyl cyclase assays (rat CL, rabbit CL, and pig follicles), consistent with the possibility that AC receptors are responsible for biologic actions of LH.