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PubMed2000

[The men of the Andrée expedition probably died of botulism. A new hypothesis explains these mysterious deaths].

The last camp of the three members of the 1897 Swedish Andrée balloon expedition to the North Pole was found in Svalbard in 1930. The human remains and the paraphernalia of the expedition including diaries were brought to Sweden and are presently housed in a museum. The cause of the deaths has never been determined, but several hypotheses have been put forward over the years. Trichinosis, scurvy, and poisoning by carbon-monoxide, vitamin-A or lead are some of them. In this article it is argued that botulism is a plausible explanation which is in better accord with known facts.

Botulism↗
PubMed1995

[The Madrid Royal Academy of Medicine and botanical expeditions during the Enlightenment. A pharmacological-therapeutical connection].

We studied the repercussions of Enlightenment botanical expeditions on pharmacological controversies that arose within the Royal Academy of Medicine in Madrid. The main contributors to the knowledge of pharmacological and therapeutic properties of American flora were José Pavón, and especially Hipólito Ruiz, of the Oficina de la Flora Americana. Contributions by other participants in expeditions were rare, and are limited to the writings of Vicente Cervantes, Martín Sessé and José Mariano Mociño, botanists who traveled to New Spain.

Academies and Institutes↗
PubMed2002

People challenges in biospheric systems for long-term habitation in remote areas, space stations, moon, and Mars expeditions.

People who participate in remote and difficult expeditions, such as the 2-year (1991-1993) Biosphere 2 experiment or a future biospheric system on Mars or other long voyages, will face individual psycho-physiological, social, and cultural value challenges. The individual psycho-physiological vectors include the lure of being a hero/heroine and pushing it to the maximum, concealment of problems with the belief that he/she can overcome the obstacle alone, as well as the difficulty of keeping intact the critical differentiation of the risks associated with the overall expedition as opposed to the experimental objectives. The social challenges occur as a group dynamic context as well as for the individual, resulting in regressions and the need to "act out" one's difficulties. Cultural areas of importance that must be taken into consideration will include esthetic, ethical, cosmological, and epistemological values. The epistemological values must involve the five methods of scientific inquiry for a comprehensive total systems project to succeed fully.

Adaptation, Psychological↗
PubMed2003

[The challenges for physicians on polar expeditions around the year 1900].

One century ago there was an intense activity in exploring the unknown polar areas. The paper gives an account of 14 expeditions involving 17 physicians. For several years, the official versions were those published by the leaders of the expeditions, the heroes. During the last years, however, the diaries of their companions have been published and provide valuable and rectifying information. Surprisingly, most of the physicians were young and inexperienced and unfit for the extreme strain of the polar areas.

Antarctic Regions↗
PubMed1983

Physicians on Mount Everest. A clinical account of the 1981 American Medical Research Expedition to Everest.

The American Medical Research Expedition to Everest had a wide variety of medical problems, ranging from leech bites to high-altitude pulmonary edema. Preventive measures, however, such as careful attention to ingesting only pure water and food at the lower elevations and adequate personal hydration, nutrition and rest at extremely high altitude minimized the morbidity suffered by the group. Prophylactic administration of doxycycline was effective in reducing the severity of diarrheal illness in the group. Every member of the expedition suffered upper respiratory tract infections and many other infections, some of which were resistant to all therapy until the patient moved down from high altitude. Despite careful acclimatization, several cases of acute mountain sickness occurred and required descent to a lower altitude for treatment. Frostbite was avoided entirely.

Altitude Sickness↗
PubMed2000

Undermining the Baldwin expediting effect: does phenotypic plasticity accelerate evolution?

The claim that phenotypic plasticity speeds up evolution towards a target phenotype is a recent incarnation of the Baldwin effect. To differentiate this theory from earlier interpretations of Baldwin's ideas, we name it the Baldwin expediting effect. Models that demonstrate this effect assume an extreme fitness scenario which bestows high fitness upon a single optimal phenotype and treats all other phenotypes as equal. In two modeling frameworks, we demonstrate that the effects of plasticity on the rate of evolution are highly dependent on the fitness function and population starting conditions. We argue that phenotypic plasticity does not universally facilitate evolution. Furthermore, in cases where the Baldwin expediting effect occurs, it is not necessarily correlated with increased fitness and therefore is not sufficient to explain the evolutionary success of plasticity.

Biological Evolution↗
PubMed1984

Evaluation of sympathoadrenal activity, adrenocortical function and androgenic status in five men during a Himalayan mountaineering expedition (ascent of Mt Pabil, 7,102 m, 23,294 ft).

Sympathoadrenal activity, adrenocortical function and androgenic status were studied in five well-trained mountaineers during the different phases of a mountaineering expedition during the ascent of Mt Pabil (7,102 m) in the Ganesh Himal massif. Sympathoadrenal activity was evaluated by measuring urinary excretion of adrenaline, noradrenaline, metanephrines, and vanillinmandelic acid. Adrenocortical function was assessed by measuring urinary excretion of free cortisol, 17 OHCS (17-hydroxycorticosteroids) and androgenic status by measuring testosterone glucuronide, Adiol (5 alpha-androstane-3 alpha, 17 beta diol) and 17KS (17-ketosteroids). Reference values were obtained at Chamonix at 1,037 m during rest. During trekking noradrenaline increased significantly while Adiol and 17-KS decreased. The fall in the urinary androgenic pool persisted during the next phases of the expedition. At base camp (4,800 m) noradrenaline, its metabolites and free cortisol increased mainly during physical activity. Above 6,000 m, adrenaline, noradrenaline, their metabolites, free cortisol and 17-OHCS reached a maximum value. During the return to sea level, the urinary level of these parameters was still high. The drop in the urinary androgenic pool observed during trekking and exposure to high altitude confirms results obtained in other studies on prolonged efforts. This hypoandrogenicity may play an important role in the metabolic adaptations as well as in the mental state of the climbers. The increase of sympathoadrenal activity and of adrenocortical function may be considered as a regulatory element in the adaptative response to hypoxia and other stressors proper to high altitude.

17-Hydroxycorticosteroids↗
PubMed1996

Effect of seasonal ultraviolet radiation fluctuations on vitamin D homeostasis during an Antarctic expedition.

Antarctica is a unique and challenging environment where members of expeditions face a range of conditions not normally experienced. Ultraviolet (uv) radiation levels show marked variation during the year. The 25-hydroxy metabolite of vitamin D [25(OH)D] is largely produced by sunlight and shows a yearly variation in concentration that corresponds to uv radiation levels. The active metabolite 1,25-dihydroxyvitamin D [1,25(OH)2D] does not generally show any such variation provided 25(OH)D concentrations are sufficient. Previous studies have shown a seasonal variation in 25(OH)D with a significant winter drop. No other study of 1,25(OH)2D has been reported on members of Antarctic expeditions. A group of 19 men wintering at Davis Station (68 degrees 34' S) had four blood samples taken at 3-monthly intervals beginning in the Antarctic summer. Analysis for 25(OH)D showed a drop in concentration for each of the latter three sampling periods (P < 0.005). This correlated with uv radiation levels and would suggest that endogenous production of 25(OH)D ceases for at least the duration of the Antarctic winter. There were no significant alterations in 1,25(OH)2D or calcium concentrations over the same period. Providing that individuals with pre-existing vitamin D deficiencies are detected before departure for Antarctica and missions are limited in duration, clinical deficiency is unlikely to occur.

Adult↗
PubMed2004

Using multimedia modeling to expedite site characterization.

GOAL, SCOPE AND BACKGROUND: This paper uses two case studies of U.S. Department of Energy nuclear weapons complex installations to illustrate the integration of expedited site characterization (ESC) and multimedia modeling in the remedial action decision making process. CONCEPTUAL SITE MODELS, MULTIMEDIA MODELS, AND EXPEDITED SITE CHARACTERIZATION: Conceptual site models outline assumptions about contaminates and the spatial/temporal distribution of potential receptors. Multimedia models simulate contaminant transport and fate through multiple environmental media, estimate potential human exposure via specific exposure pathways, and estimate the risk of cancer and non-cancer health outcomes. ESC relies on using monitoring data to quantify the key components of an initial conceptual site model that is modified iteratively using the multimedia model. CASE STUDIES: Two case studies are presented that used the ESC approach: Los Alamos National Laboratory (LANL) and Pantex. LANL released radionuclides, metals, and organic compounds, into canyons surrounding the facility. The Pantex Plant has past waste management operations which included burning chemical wastes in unlined pits, burying wastes in unlined landfills, and discharging plant wastewaters into on-site surface waters. CONCLUSIONS: The case studies indicate that using multimedia models with the ESC approach can inform assessors about what, where, and how much site characterization data needs to be collected to reduce the uncertainty associated with risk assessment. Lowering the degree of uncertainty reduces the time and cost associated with assessing potential risk and increases the confidence that decision makers have in the assessments performed.

Decision Making↗
PubMed2006

Expedited partner therapy for adolescents diagnosed with gonorrhea or chlamydia: a review and commentary.

Management of sex partners is a cornerstone of sexually transmitted infection control in the United States. Face-to-face investigation and notification of exposure of sex partners by public health professionals seems to be the most effective method of ensuring appropriate partner management. However, resources rarely permit such intensive partner management for gonorrhea and chlamydial infection. Alternatives to public health-assisted notification and referral include expedited partner therapy, in which partners are treated before evaluation, most typically through patient-delivered therapy. Results from trials have shown generally favorable biomedical and behavioral outcomes. This article discusses the evidence for expedited partner therapy and its associated liability, confidentiality, financial, and administrative issues relating to adolescent patients and their health care providers.

Adolescent↗
PubMedDate not supplied

Some approaches to medical support for Martian expedition.

Medical support in a Martian expedition will be within the scope of crew responsibilities and maximally autonomous. Requirements to the system of diagnostics in this mission include considerable use of means and methods of visualization of the main physiological parameters, telemedicine, broad usage of biochemical analyses (including "dry" chemistry), computerized collection, measurement, analysis and storage of medical information. The countermeasure system will be based on objective methods of crew fitness and working ability evaluation, individual selection of training regimens, and intensive use of computer controlled training. Implementation of the above principles implies modernization and refinement of the countermeasures currently used by space crews of long-term missions (LTM), and increases of the assortment of active and passive training devices, among them a short-arm centrifuge. The system of medical care with the functions of prevention, clinical diagnostics and timely treatment will be autonomous, too. The general requirements to medical care during the future mission are the following: availability of conditions and means for autonomous urgent and special medical aid and treatment of the most possible states and diseases, "a hospital", and assignment to the crew of one or two doctors. To ensure independence of medical support and medical care in an expedition to Mars an automated expert system needs to be designed and constructed to control the medical situation as a whole.

Adaptation, Physiological↗
PubMed2005

Polybrominated diphenyl ethers in airborne particulates collected during a research expedition from the Bohai Sea to the Arctic.

In July to September 2003, particulates in the oceanic atmosphere from the Bohai Sea to the high Arctic (37 degrees N to 80 degrees N) were collected aboard a research expedition icebreaker, Xuelong (Snow Dragon), under the 2003 Chinese Arctic Research Expedition Program (CHINARE 2003). These samples were analyzed to elucidate the atmospheric distributions of polybrominated diphenyl ethers (PBDEs) in the North Pacific Ocean and adjacent Arctic region. The levels of 11 PBDE congeners (BDE-28, -47, -66, -100, -99, -85, -154, -153, -138, -183, and -209; the sum was defined as sigma11PBDE) in the oceanic atmosphere of Far East Asia (34-48 degrees N/122-148 degrees E) ranged from 2.25 to 198.9 pg/m3 with a mean of 58.3 pg/m3. BDE-47, -99, -100, and -209 were the dominant congeners in all the samples, suggesting that the widely used commercial penta- and deca-BDE products were the original sources. The PBDE levels exhibited a decreasing trend from the mid- to high-latitudinal regions of the North Pacific Ocean, probably resulting from dilution, deposition, and decomposition of PBDEs during long-range transport of air masses. On the other hand, no apparent geographical pattern of PBDE distribution was observed within the Arctic, attributable to unstable air circulation and strong air mixing. Correlations among the PBDE congeners suggested that air masses collected from the North Pacific Ocean were relatively fresh, whereas those from the Arctic were aged as a result of photodecompoisiton. The higher average level (17.3 pg/m3) of PBDE congeners in the Arctic than those in the adjacent North Pacific Ocean (12.8 pg/m3) or other remote areas reported in the literature was attributed to the impact of the North American continent and temperature effects, which was consistent with the hypotheses of global fractionation.

Air Movements↗
PubMed2002

Neuropathic pain and dysesthesia of the feet after Himalayan expeditions.

High altitude peripheral nerve disease secondary to frostbite or trauma is a well-recognized medical problem during mountaineering expeditions. However, in our experience as medical professionals on 19 expeditions to the Himalayas in the years 1977 to 2000, an unusual syndrome of neuropathic pain and/or dysesthesia in both feet apparently unrelated to frostbite or trench foot was observed in 8 (4.8%) of 165 European mountaineers. Mountaineers complained of persistent and continuous pain, which was consistently described as a "corky" sensation in their feet, associated with severe lancinating exacerbations. Pain improved with cold and worsened with heat and gentle pressure. Symptoms were incapacitating in a third of the cases. Treatment with carbamazepine was effective, and the disorder evolved to total resolution in 4 to 8 weeks. We present the case of a patient who had this syndrome and in whom complete work-up studies done on his arrival home, 14 days after its presentation, were unrevealing. The paucity of information regarding this particular variety of neuropathic pain of the feet may be due to lack of clinical suspicion in the field, favorable outcome, and difficulties for further study and evaluation.

Adult↗
PubMed2002

A year's experience as advisory doctor to a commercial mountaineering expedition company.

The purpose of this paper is to outline one U.K. doctor's experience as advisor to a British commercial high altitude expedition company. Within the United Kingdom, this is pioneering work, and various aspects of the job are outlined that have evolved in response to the current medical needs and market forces. The U.K. medicolegal aspects of the work are considered in the light of there being no current case law to guide doctors in this role. With more people worldwide making use of commercial companies for expeditions with the associated duty of care, it is hoped that this will stimulate further debate on some potentially delicate issues that cross international boundaries.

Altitude Sickness↗
PubMed2000

Downregulation in muscle Na(+)-K(+)-ATPase following a 21-day expedition to 6,194 m.

To investigate the hypothesis that acclimatization to altitude would result in a downregulation in muscle Na(+)-K(+)-ATPase pump concentration, tissue samples were obtained from the vastus lateralis muscle of six volunteers (5 males and 1 female), ranging in age from 24 to 35 yr, both before and within 3 days after a 21-day expedition to the summit of Mount Denali, Alaska (6,194 m). Na(+)-K(+)-ATPase, measured by the [(3)H]ouabain-binding technique, decreased by 13.8% [348 +/- 12 vs. 300 +/- 7.6 (SE) pmol/g wet wt; P < 0.05]. No changes were found in the maximal activities (mol. kg protein(-1). h(-1)) of the mitochondrial enzymes, succinic dehydrogenase (3.63 +/- 0.20 vs. 3.25 +/- 0.23), citrate synthase (4. 76 +/- 0.44 vs. 4.94 +/- 0.44), and malate dehydrogenase (12.6 +/- 1. 8 vs. 12.7 +/- 1.2). Similarly, the expedition had no effect on any of the histochemical properties examined, namely fiber-type distribution (types I, IIA, IIB, IC, IIC, IIAB), area, capillarization, and succinic dehydrogenase activity. Peak aerobic power (52.3 +/- 2.1 vs. 50.6 +/- 1.9 ml. kg(-1). min(-1)) and body mass (76.9 +/- 3.7 vs. 75.5 +/- 2.9 kg) were also unaffected. We concluded that acclimatization to altitude results in a downregulation in muscle Na(+)-K(+)-ATPase pump concentration, which occurs without changes in oxidative potential and other fiber-type histochemical properties.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1988

Utilizing angiogenic agents to expedite the neovascularization process in skin flaps.

The revascularization of a skin flap after flap transposition is an important step in flap survival. This study investigates the efficacy of certain angiogenic agents to expedite the neovascularization process and to increase the viability of skin flaps. Eighty-four island skin flaps were designed on the auricles of 42 New Zealand White rabbits to achieve 90% necrosis over a 7-day period. Thirty-six flaps were treated with Endothelial Cell Growth Supplement (ECGS) or Endothelial Cell Growth Factor (ECGF) at several concentrations topically or immersed in Gelfoam. The remaining flaps were used as normal saline controls. Flap viability and peripheral neovascularization were documented by polar planimetry, angiography, and histological analysis. The flap viability of the ECGS-Gelfoam -treated flaps was 100% greater than their normal saline-Gelfoam controls (p = .021). Flap angiograms demonstrated increased vascular ingrowth among the treated flaps compared to the controls. This study suggests that angiogenic agents can expedite flap neovascularization and have the potential to increase flap viability.

Administration, Topical↗
PubMed2000

Expedited human immunodeficiency virus testing of mothers and newborns with unknown HIV status at time of labor and delivery.

New York State introduced the first statewide program in the U.S. of expedited HIV testing (48-hour turn-around results) of mothers with unknown HIV status at the time of labor or delivery and their newborns on August 1, 1999. We evaluated the results of this program during its first 5 months at Lincoln Medical and Mental Health Center (Lincoln Hospital) in the Bronx, New York. There were 1,274 total live birth deliveries between August 1 and December 31, 1999. The HIV infection status of 539 mothers (42.3%) was unknown to medical providers in the labor-delivery suite, either due to lack of testing during the current pregnancy or unavailability of HIV documentation at the time of delivery. During labor and delivery, a total of 462 (85.7%) mothers with unknown HIV status consented to expedited HIV testing (Single Use Diagnostic System for HIV-1 antibody or SUDS). The newborns of 77 mothers (14.3%) who did not consent were tested immediately after birth. Seventeen tested positive for HIV-1 antibody by the SUDS test. The results of 10 of these infants (58.8%) were subsequently confirmed positive for HIV-1 antibody by Western Blot analysis. This new rapid HIV testing program facilitated early diagnosis of these previously unknown HIV-exposed infants, although the low positive predictive value of the test in our community calls for careful communication of these results pending confirmation.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Protection of human subjects: categories of research that may be reviewed by the Institutional Review Board (IRB) through an expedited review procedure--FDA. Notice.

On November 10, 1997, the Food and Drug Administration (FDA), in consultation with the Office for Protection from Research Risks (OPRR) at the National Institutes of Health, requested written comments relating to the proposed republication of the list that identifies certain research activities involving human subjects that may be reviewed by the Institutional Review Board (IRB) through the expedited review procedure authorized in 21 CFR 56.110. The comment period closed on March 10, 1998. FDA and OPRR received a combined total of 108 comments. After a review of the comments, FDA and OPRR are now simultaneously publishing identical revised lists of categories of research activities that may be reviewed by the IRB through the expedited review procedure.

Human Experimentation↗