Probe angioplasty of total coronary occlusion using an intracoronary Probing Catheter

Coronary angioplasty (PTCA) of total coronary occlusion is limited by the inability of guidewires and conventional dilating catheters to cross all such lesions. We have therefore developed a technique for PTCA of chronic total coronary occlusions using the ultralow profile "balloon-on-a-wire" Probe. An intracoronary Probing Catheter is used to facilitate crossing the stenosis with a guidewire and then to deliver a Probe into the obstruction for balloon dilatation. This technique was used in 13 patients including six in whom other dilating systems had failed to cross the occlusion. Successful dilatation was performed in nine patients (67%). Among the six patients in whom other dilating systems had failed, dilatation was performed in five using the Probing Catheter technique with a successful outcome achieved in four (67%). The Probing Catheter technique offers a promising new method to apply "balloon-on-a-wire" technology to the dilatation of chronic total coronary occlusions. This method may allow successful dilatation when other dilating systems fail.     

Low-density lipoproteins inhibit histamine and NaNO2 relaxations of the coronary vasculature and reduce contractile function in isolated rat hearts

Summary In the present study we examined the action of native and oxidized low-density lipoproteins (LDL) on coronary vascular and cardiac function and ultrastructure in rat hearts perfused isovolumically in the Langendorff mode. Responses of the coronary resistance vessels to the endothelium-dependent vasodilator, histamine, and the endothelium-independent vasodilator, NaNO₂, were measured together with contractile function (rate-pressure product) before and after perfusion for 20 min with native — or oxidized-LDL at a concentration of 100 µg protein/ml. Ultrastructural damage was assessed via electron microscopy of perfusion-fixed heart specimens. When compared to findings in untreated, control hearts, both native and oxidized LDL significantly reduced the responsiveness of the coronary resistance vessels to histamine and NaNO₂, by about 50%. The rate-pressure product was decreased more by oxidized-LDL (41%) than by native-LDL (26%). Electron microscopy showed no ultrastructural abnormalities in the vasculature or myocytes of control hearts. The administration of both native- and oxidized-LDL caused distortion of endothelial cells, increased levels of pinocytotic vesicles in both endothelial and smooth muscle cells, detachment of blood vessels from surrounding tissue, and some regions of myocyte injury with evidence of mitochondrial injury and fluid accumulation. Our results show that both native- and oxidized-LDL are toxic to the isolated heart preparation. They inhibit coronary vascular responsiveness to vasodilators, reduce contractile function, and produce damage to cardiac ultrastructure.     

Hormones and bone health in postmenopausal women

Although it has been known for some time that estrogen deficiency is a major pathogenetic factor for osteoporosis related fractures among postmenopausal women, the capability of estrogen (with or without a progestin) to prevent fractures has often been questioned. The publication of the data from the two hormone clinical trials of the Women’s Health Initiative lays that discussion to rest. In both studies what have been considered a standard dose of conjugated estrogen with or without medroxyprogesterone acetate significantly reduced the risk of all fractures, including clinical vertebral fractures and hip fracture, in a population of postmenopausal women, average age 63 yr, not selected for osteoporosis by BMD. These results are particularly impressive given the difficulty of finding a fracture benefit in lower risk populations with other anti-resorptive agents. Surrogate data on lower doses of hormone therapy suggest a fracture benefit would be seen if studies were to be done. The other outcomes in WHI make it important to define appropriate clinical guidelines for use of hormone therapy for prevention of fractures in postmenopausal women.     

Changes in house design reduce exposure to malaria mosquitoes

House design may affect an individual's exposure to malaria parasites, and hence to disease. We conducted a randomized-controlled study using experimental huts in rural Gambia, to determine whether installing a ceiling or closing the eaves could protect people from malaria mosquitoes. Five treatments were tested against a control hut: plywood ceiling; synthetic-netting ceiling; insecticide-treated synthetic-netting ceiling (deltamethrin 12.5 mg/m2); plastic insect-screen ceiling; or the eaves closed with mud. The acceptability of such interventions was investigated by discussions with local communities. House entry by Anopheles gambiae, the principal African malaria vector, was reduced by the presence of a ceiling: plywood (59% reduction), synthetic-netting (79%), insecticide-treated synthetic-netting (78%), plastic insect-screen (80%, P < 0.001 in all cases) and closed eaves (37%, ns). Similar reductions were also seen with Mansonia spp., vectors of lymphatic filariasis and numerous arboviruses. Netting and insect-screen ceilings probably work as decoy traps attracting mosquitoes into the roof space, but not the room. Ceilings are likely to be well accepted and may be of greatest benefit in areas of low to moderate transmission and when used in combination with other malaria control strategies.     

Tom Tiddler’s Ground: Irregular Medical Practitioners and Male Sexual Problems in New Zealand, 1858–1908

Irregular practitioners (‘quacks’) specialising in male sexual problems succeeded in nineteenth-century New Zealand by taking advantage of the growing population of unattached men who were ignorant of their own sexual physiology. The irregulars also profited from the regular practitioners’ acceptance of ill-defined or imaginary male sexual disorders and the side effects of conventional venereal disease treatments, the lack of a clear demarcation between quacks and the regular medical profession, and an increased availability of newspaper advertising. Improvements in the postal system enabled quacks to reach more potential customers by mail, their preferred sales method. The decline in quackery resulted from scientific advances in the understanding of disease and government legislation to privilege regular practitioners and limit quacks’ access to postal services and advertising. Keywords : Sexuality, Quackery, Masturbation, Spermatorrhoea, Electrotherapy     

Myocarditis,Microbes and Autoimmunity

Acute and chronic myocarditis can be caused by a number of infectious agents, including viruses, bacteria and protozoa. These diseases are refractory to treatment, and the development of rational therapies will require a detailed understanding of the mechanisms that underlie the pathological inflammatory responses. Here, we review three infectious myocarditides that, despite the dissimilarity of the microorganisms, share several common features: (i) the microbes replicate in the heart; but (ii) are difficult to isolate, in infectious form, during chronic disease; (iii) autoreactive antibodies and T cells specific for cardiac antigens have been identified in infected animals; and (iv) these autoreactive responses have been proposed as the main effectors of cell death, and myocardial damage. We critically evaluate the data, and we suggest that the findings can be reconciled without invoking autoimmunity as an effector mechanism. Alternative hypotheses to explain the tissue destruction are proposed.     

A five-year clinical audit of concussive injuries in South African collegiate male rugby players—a South African experience

Sport Sciences for Health - Sports-related concussion (SRC) is a common injury mostly in contact sports. Specifically, it is a public health concern for collegiate rugby athletes because at least...     

Reduced Motivation in Perinatal Fluoxetine-Treated Mice: A Hypodopaminergic Phenotype

Early life is a sensitive period, in which enhanced neural plasticity allows the developing brain to adapt to its environment. This plasticity can also be a risk factor in which maladaptive development can lead to long-lasting behavioral deficits. Here, we test how early-life exposure to the selective-serotonin-reuptake-inhibitor (SSRI), fluoxetine, affects motivation, and dopaminergic signaling in adulthood. We show for the first time that mice exposed to fluoxetine in the early postnatal period exhibit a reduction in effort-related motivation. These mice also show blunted responses to amphetamine and reduced dopaminergic activation in a sucrose reward task. Interestingly, we find that the reduction in motivation can be rescued in the adult by administering bupropion, a dopamine-norepinephrine reuptake inhibitor used as an antidepressant and a smoke cessation aid but not by fluoxetine. Taken together, our studies highlight the effects of early postnatal exposure of fluoxetine on motivation and demonstrate the involvement of the dopaminergic system in this process.SIGNIFICANCE STATEMENT The developmental period is characterized by enhanced plasticity. During this period, environmental factors have the potential to lead to enduring behavioral changes. Here, we show that exposure to the SSRI fluoxetine during a restricted period in early life leads to a reduction in adult motivation. We further show that this reduction is associated with decreased dopaminergic responsivity. Finally, we show that motivational deficits induced by early-life fluoxetine exposure can be rescued by adult administration of bupropion but not by fluoxetine.