Evidence of discrete yellowfin tuna (Thunnus albacares) populations demands rethink of management for this globally important resource.

Tropical tuna fisheries are central to food security and economic development of many regions of the world. Contemporary population assessment and management generally assume these fisheries exploit a single mixed spawning population, within ocean basins. To date population genetics has lacked the required power to conclusively test this assumption. Here we demonstrate heterogeneous population structure among yellowfin tuna sampled at three locations across the Pacific Ocean (western, central, and eastern) via analysis of double digest restriction-site associated DNA using Next Generation Sequencing technology. The differences among locations are such that individuals sampled from one of the three regions examined can be assigned with close to 100% accuracy demonstrating the power of this approach for providing practical markers for fishery independent verification of catch provenance in a way not achieved by previous techniques. Given these results, an extended pan-tropical survey of yellowfin tuna using this approach will not only help combat the largest threat to sustainable fisheries (i.e. illegal, unreported, and unregulated fishing) but will also provide a basis to transform current monitoring, assessment, and management approaches for this globally significant species.

The experience of "medicine companions" to support adherence to antiretroviral therapy: quantitative and qualitative data from a trial population in Uganda.

Good adherence is critical for antiretroviral therapy (ART) in sub-Saharan Africa. We report on the characteristics of medicine companions (MCs) chosen by Ugandan patients enrolling on ART, and on how MCs were chosen, and what roles they played. Baseline data on MCs of 1453 participants in a randomized controlled trial comparing facility and home-based delivery of ART in Jinja, Uganda were analyzed. Textual data on experience with MCs were collected through in-depth interviews among a subsample of 40 trial participants equally divided by sex and trial arm. Significantly more women (71%) than men (29%) were recruited. The majority (75%) of women participants were either widowed (51%) or separated or divorced (24%), whereas most of the men (66%) were married. Women were most likely to choose a child as their MC while men were most likely to choose their spouse; 41% of women chose an MC under 21 compared with only 14% of men. Only 31% of married women chose their husband, compared with 66% of married men who chose their wife. Qualitative interviews suggested MCs proved useful for reminding and other supportive tasks in the first three months but were generally less essential by six months and beyond. Convenience, reliability, and trust were key considerations in choosing an MC. Children provided the only alternative for many unmarried women, but even some married women felt children made more reliable MCs than husbands. Participants who had disclosed their serostatus usually received drug-taking reminders from multiple household members. One participant in the qualitative sample with poor family relations delayed starting treatment due to unwillingness to identify an MC. MCs were generally welcome and useful in supporting early adherence. However, disclosure to an MC should not be a condition of obtaining treatment.

Socio-economic, gender and health services factors affecting diagnostic delay for tuberculosis patients in urban Zambia.

In-depth interviews regarding health seeking behaviour were conducted with 202 adults registered with pulmonary tuberculosis at the centralized Chest Clinic in Lusaka, Zambia. The median (mean) diagnostic delay was 8.6 (9) weeks, and was significantly associated with the following factors: female sex, lower education, more than six instances of health-seeking encounters, outpatient diagnosis of tuberculosis, and visiting a private doctor or traditional healer. More effective tuberculosis control interventions require novel methods of accessing women and less educated people. Decentralization of public tuberculosis care and improved integration with private sector health providers may also reduce diagnostic delay.

Barriers to tuberculosis control in urban Zambia: the economic impact and burden on patients prior to diagnosis.

SETTING: Chest Clinic, University Teaching Hospital, Zambia. OBJECTIVE: To study the pre-diagnosis economic impact, burden, and barriers to care-seeking for tuberculosis patients in urban Zambia. DESIGN: In-depth interviews conducted over a 9-week period with adult in-patients and out-patients registering with new pulmonary tuberculosis; data analysis using Epi Info. RESULTS: Interviews were completed by 202 patients: 64% normally worked, but 31% stopped due to their tuberculosis, with an average of 48 days off. The mean duration of illness prior to their tuberculosis registration was 63 days, with 64% of patients delaying in presenting to the Chest Clinic. Of these, 38% blamed money shortages for their delay. In seeking diagnosis, patients incurred a mean total cost equivalent to 127% of their mean monthly income (pounds sterling UK 40 [$US 59]); direct expenditures represented 60% of this cost. In addition, patients lost, on average, 18 work days prior to diagnosis. Care-givers incurred costs equivalent to 31% of the mean monthly income (pounds sterling UK 10 [$US 15]). CONCLUSION: The economic burden of tuberculosis on patients creates barriers to prompt diagnosis which may lead to continuing transmission of the infection. Important economic barriers include transportation expenditure, cost of 'special food', and lost income. These barriers may be reduced through interventions that reduce the number of health encounters, travel distances and duration of illness before diagnosis.

Human and bovine tuberculosis in the Monze District of Zambia--a cross-sectional study.

One hundred and seventy-six randomly selected rural households in the Monze District of Zambia were interviewed; 103 of these presented cattle for tuberculin testing. Of the 2226 cattle tested, 165 (7.4%) were positive reactors; 33% of herds contained positive animals. Risk of a positive reaction varied with an animal's age and body condition. Cattle in larger herds were more likely to give positive reactions. Ten households reported a human case of tuberculosis (TB) during the preceding 12 months; the herds or these households were six times more likely to have a tuberculin-positive animal than herds in households without a reported human TB case.

CRNAs: an enviable legacy of patient service.

The profession of nurse anesthesia and the role of the certified registered nurse anesthetist (CRNA) is chronicled to acquaint the general nursing population and those within advanced practice specialties of nursing to the discipline of anesthesiology. Historical highlights, professional definitions, scope of practice, insights into the educational preparation of CRNAs, employment settings, and marketplace opportunities are described. Professional challenges and opportunities facing CRNAs have come from both within and outside the nursing community. By facing these challenges CRNAs have demonstrated their tenacity in professional commitment to the delivery of quality patient care for more than 100 years.

Cutaneous reactions to thiacetazone in Zambia--implications for tuberculosis treatment strategies.

Tuberculosis in patients infected with human immunodeficiency virus (HIV) is a growing threat to public health in Africa. Thiacetazone, one of the continent's most widely used antituberculous agents, may lead to severe cutaneous reactions in the HIV infected individual. We describe the impact of this reaction on the tuberculosis (TB) control programme of a district hospital in Zambia in 1990, and examine the cost implications of changing the standard treatment regime. We carried out a retrospective survey of records of all patients beginning TB treatment in 1990, together with HIV test results and the cost of all treatments given. From this we derived estimates of costs of different regimes which are and could be used in TB control in Zambia. Severe reactions occurred in 18.7% of all HIV seropositive patients receiving thiacetazone, fatally so in 1.2% (odds ratio 16.6). The greatest part of the cost of the current regime is that attributable to the inpatient stay; we estimated that 29.4% of patients would be unable to receive drugs as out-patients but, even allowing for this, rifampicin-based regimes given to outpatients where possible would not cost more than the current strategy. We conclude that ethical and economic considerations support a change to rifampicin-based regimes in areas of Africa where HIV seroprevalence is high.

The literature and perspectives on muscle relaxants for rapid sequence induction.

Since the advent of surgical anesthesia, one of the single greatest challenges to providers and researchers has been to develop, test, and promote drugs and techniques to facilitate rapid intubation and security of the airway to diminish risk of regurgitation and gastric aspiration. This article provides a comprehensive, historical perspective of such efforts, including the efficacy of various techniques and muscle relaxant drugs that have been used to further the ideal situation in which airway control would obviate the all-too-common morbidity statistics of gastric aspiration. Special emphasis is given to the review of succinylcholine and vecuronium relative to their roles in rapid sequence induction.

New advances in anesthesia.

Pharmacologic advances in anesthesia over the last decade have focused on drug safety, shorter durations of action, reversibility, and ease of administration. This is reflective of major changes in the focus of patient care from inpatient to outpatient settings as well as from available risk management data that support the investigation of these new drugs. The pharmacologic advances discussed included those drugs in current practice as well as experimental drugs yet to be released for general clinical use. Inhaled agents, such as isoflurane and perhaps the experimental agent, desflurane, will maintain or achieve their popularity because of the relative ease of administration and wide margins of safety. Propofol, the most recent intravenous anesthetic available for clinical use, has already gained wide acceptance because of its dual function as an induction and maintenance agent and its appropriateness for use in the ambulatory surgical population. The role of midazolam in anesthesia practice has increased to such an extent that it has largely supplanted the use of diazepam (Valium). The introduction of the antagonist, flumazenil, will undoubtedly enhance the safety and efficacy of midazolam as well as broaden its applicability of use across various patient populations. Several of the newer synthetic narcotics, such as alfentanil and sufentanil, have replaced other narcotics formerly used in anesthesia practice, such as meperidine and morphine, primarily because of their short action and lack of significant side effects. The use of muscle relaxants as a critical component of anesthetic management has led to the development of a number of new drugs in this classification. Pharmacologic management of patients under anesthesia will at some future date likely include the administration of alpha 2 agonists. Administration of these drugs can reduce anesthetic requirements of traditional agents by as much as 50%. As research continues, new drugs will be incorporated into the practice of anesthesia, ones that will promote rapid uptake, low toxicity, intense analgesia, easy reversibility, shorter durations, and fewer side effects. One measure of success relative to pharmacologic development in anesthesia is the recent and dramatic decreases in patient morbidity and mortality figures over the last decade. This attests to the rapid growth and development of not only improved patient monitoring systems but also newly improved "agents of sleep."

Anesthetic and hemodynamic effects of dexmedetomidine during isoflurane anesthesia in a canine model.

Dexmedetomidine, an alpha 2-adrenergic agonist, was administered during isoflurane anesthesia to investigate its anesthetic sparing and hemodynamic effects in the canine model. Eleven healthy dogs were anesthetized with isoflurane, intubated, and allowed to breathe spontaneously. The animals were instrumented in order to measure or calculate mean arterial blood pressure (MABP), heart rate (HR), left ventricular end diastolic pressure (LVEDP), cardiac output (CO), and systemic vascular resistance (SVR). Isoflurane minimum alveolar concentration (MAC), baseline hemodynamic measurements, and plasma catecholamine levels were determined. A 20 micrograms/kg bolus of dexmedetomidine was injected intravenously (IV) and MAC and hemodynamic values were redetermined. When isoflurane requirements were 33% of baseline, isoflurane was returned to 90% MAC and the alpha 2-antagonist, atipamezole, was administered. All dogs were treated with 40 micrograms/kg glycopyrrolate throughout the experiment to prevent any bradycardic response. Dexmedetomidine reduced isoflurane MAC by 86%. SVR, MABP, and LVEDP were significantly increased while CO and catechloamine levels were reduced. Atipamezole fully reversed the reduction in anesthetic requirements. MABP and catecholamine levels returned to baseline. SVR and LVEDP increased while CO decreased. The dogs exhibited a profound reduction in anesthetic requirement, reduced catecholamine levels, and changes in hemodynamic parameters with dexmedetomidine administration. The anesthetic sparing effect appears to be mediated by the alpha 2-receptor, since atipamezole reversed the reduction in MAC. Hemodynamic changes may be species or dose related, or due to differences in existing sympathetic tone. The role of dexmedetomidine warrants further study as an adjunct anesthetic agent.

Pricing, distribution, and use of antimalarial drugs.

Prices of new antimalarial drugs are targeted at the "travellers' market" in developed countries, which makes them unaffordable in malaria-endemic countries where the per capita annual drug expenditures are US$ 5 or less. Antimalarials are distributed through a variety of channels in both public and private sectors, the official malaria control programmes accounting for 25-30% of chloroquine distribution. The unofficial drug sellers in markets, streets, and village shops account for as much as half of antimalarials distributed in many developing countries. Use of antimalarials through the health services is often poor; drug shortages are common and overprescription and overuse of injections are significant problems. Anxiety over drug costs may prevent patients from getting the necessary treatment for malaria, especially because of the seasonal appearance of this disease when people's cash reserves are very low. The high costs may lead them to unofficial sources, which will sell a single tablet instead of a complete course of treatment, and subsequently to increased, often irrational demand for more drugs and more injections. Increasingly people are resorting to self-medication for malaria, which may cause delays in seeking proper treatment in cases of failure, especially in areas where chloroquine resistance has increased rapidly. Self-medication is now widespread, and measures to restrict the illicit sale of drugs have been unsuccessful. The "unofficial" channels thus represent an unacknowledged extension of the health services in many countries; suggestions are advanced to encourage better self-medication by increasing the knowledge base among the population at large (mothers, schoolchildren, market sellers, and shopkeepers), with an emphasis on correct dosing and on the importance of seeking further treatment without delay, if necessary.