Climate change and the future of California's endemic flora.

The flora of California, a global biodiversity hotspot, includes 2387 endemic plant taxa. With anticipated climate change, we project that up to 66% will experience >80% reductions in range size within a century. These results are comparable with other studies of fewer species or just samples of a region's endemics. Projected reductions depend on the magnitude of future emissions and on the ability of species to disperse from their current locations. California's varied terrain could cause species to move in very different directions, breaking up present-day floras. However, our projections also identify regions where species undergoing severe range reductions may persist. Protecting these potential future refugia and facilitating species dispersal will be essential to maintain biodiversity in the face of climate change.

An overview of cholesterol management.

Cardiovascular disease is the leading cause of death worldwide. Elevated cholesterol (hypercholesterolemia) and abnormal lipid profiles (dyslipidemia) are important risk factors for the development of cardiovascular disease. This article discusses the role of cholesterol in the body and the relationship between different cholesterol fractions and the risk of cardiovascular disease. The guidelines for assessment and treatment of dyslipidemia from the National Cholesterol Education Program are outlined, and cholesterol targets and goals of therapy are discussed. The mechanism of action, place in therapy (eg, first-line, second-line, or add-on), and common side effects are also discussed for each of the available classes of drugs used in the treatment of dyslipidemia.

Optimal low-density lipoprotein is 50 to 70 mg/dl: lower is better and physiologically normal.

The normal low-density lipoprotein (LDL) cholesterol range is 50 to 70 mg/dl for native hunter-gatherers, healthy human neonates, free-living primates, and other wild mammals (all of whom do not develop atherosclerosis). Randomized trial data suggest atherosclerosis progression and coronary heart disease events are minimized when LDL is lowered to <70 mg/dl. No major safety concerns have surfaced in studies that lowered LDL to this range of 50 to 70 mg/dl. The current guidelines setting the target LDL at 100 to 115 mg/dl may lead to substantial undertreatment in high-risk individuals.

Psychosocial stress and cardiovascular disease: how to heal a broken heart.

Psychosocial stress induces adverse changes in autonomic tone accounting for substantial but modifiable cardiovascular risk. Various factors, including depression, social isolation, hostility and anxiety increase cardiovascular risk, whereas social support, altruism, faith and optimism reduce risk.

The intertidal marine lichen formed by the pyrenomycete fungus Verrucaria tavaresiae (Ascomycotina) and the brown alga Petroderma maculiforme (Phaeophyceae): thallus organization and symbiont interaction.

The thallus formed by the marine pyrenomycete fungus Verrucaria tavaresiae and the phaeophycean alga Petroderma maculiforme was studied to elucidate the organization of the symbionts, determine the type of cellular contacts between them, and evaluate the status of the symbiosis as a lichen. Hand-sectioned and resin-embedded samples were examined with light and transmission electron microscopy. Within the uppermost portion of the cellular fungal tissue, separate algal filaments were arranged anticlinally. Protrusions of the fungal cell wall penetrated into adjacent algal walls but did not enter the cell lumen. A striking feature of these penetrations was the frequent separation of algal cell wall layers and insertion of fungal wall material between them. Algal filaments grew downward intrusively between fungal cells, often penetrating deeply into the fungal cell wall. Despite the exceptional nature of the phycobiont involved, the Verrucaria tavaresiae-Petroderma maculiforme symbiosis unequivocally fits the prevailing concept of a lichen. The distinctive interpenetrations observed between symbionts may be related to the integration of their different growth forms within a coherent tissue regularly subject to mechanical stresses. Periclinal cell divisions within and just below the algal layer may serve to replenish surface tissues lost to abrasion and herbivory.

Topical ciprofloxacin/dexamethasone is superior to ciprofloxacin alone in pediatric patients with acute otitis media and otorrhea through tympanostomy tubes.

OBJECTIVE: To determine whether topical administration of a corticosteroid improves resolution of acute tympanostomy tube otorrhea when combined with topical antibiotic drops. STUDY DESIGN: Randomized, patient-masked, parallel-group, multicenter trial of topical otic ciprofloxacin/dexamethasone versus topical ciprofloxacin alone in 201 children aged 6 months to 12 years with acute otitis media with tympanostomy tubes (AOMT) of less than or equal to 3 weeks' duration and visible otorrhea. METHODS: Eligible patients were randomized to receive three drops of either ciprofloxacin 0.3%/dexamethasone 0.1% or ciprofloxacin 0.3% into the affected ear or ears twice daily for 7 days. Clinical signs and symptoms of AOMT were evaluated on days 1 (baseline), 3, 8 (end-of-therapy), and 14 (test-of-cure), and twice-daily assessments of otorrhea were recorded in patient diaries. RESULTS: The mean time to cessation of otorrhea in the microbiologically culture-positive patient population (n = 167) was significantly shorter with topical ciprofloxacin/dexamethasone than with ciprofloxacin alone (4.22 vs. 5.31 days; P =.004). This resulted in significantly better clinical responses on days 3 and 8 (P <.0001 and P =.0499, respectively). However, there were no significant differences between the two treatment groups in either the clinical response or the microbial eradication rate by day 14. CONCLUSIONS: Topical otic treatment with ciprofloxacin/dexamethasone is superior to treatment with ciprofloxacin alone and results in a faster clinical resolution in children with AOMT. The contribution of the corticosteroid in achieving a 20% reduction (1.1 day) in time to cessation of otorrhea is clinically meaningful and represents an important advance over single-agent antibiotic therapy.