Coronary Tortuosity as a New Phenotype for Ischemia without Coronary Artery Disease

BACKGROUND

Coronary arteries tend to be more tortuous than other arteries and follow the repeated flexion and relaxation movements that occur during the cardiac cycle. Coronary tortuosity (CorT) leads to changes in coronary flow with a reduction in distal perfusion pressure, which could cause myocardial ischemia.

OBJECTIVE

To assess the association between CorT and myocardial ischemia.

METHODS

Between January 2015 and December 2017, 57 patients with angina and nonobstructive coronary artery disease detected by invasive coronary angiography (ICA) were retrospectively enrolled. Angiographic variables were analyzed to assess the presence and degree of tortuosity and correlated with their respective vascular territories on stress myocardial perfusion imaging (MPI). CorT was defined as coronary arteries with three or more bend angles ≤90°, measured during diastole. Statistical significance was determined at the 5% level.

RESULTS

A total of 17 men and 40 women were enrolled (mean age 58.3 years). CorT was observed in 16 patients (28%) and in 24 of 171 arteries. There was a significant association between CorT and ischemia when analyzed per artery (p<0.0001). The angiographic factor most associated with ischemia was the number of bend angles in an epicardial artery measured at systole (p=0.021).

CONCLUSION

This study showed an association of CorT and myocardial ischemia in patients with unobstructed coronary arteries and angina. An increased number of coronary bend angles measured by angiography during systole was related to ischemia.

P5237Continued financial benefits of LATIN telemedicine program from avoiding unnecessary transfer of patients

Background

Latin America Telemedicine Infarct Network (LATIN) employed telemedicine to construct a population-based AMI program in Brazil, Colombia, Mexico, and Argentina. It increased access, accuracy and guidelines-based care and addressed fiscal issues. Previously, we demonstrated a cost and benefit analysis (CBA) of LATIN based upon avoiding unnecessary transfers and hospitalization. We have performed a scrupulous follow up of this initial observation with a long-term follow up from all expanded LATIN sites.

Purpose

To demonstrate that telemedicine avoids unnecessary transfer of patients.

Methods

784,947 patients at LATIN spokes (small clinics in remote areas) were screened and CBA measured at hubs, spokes and telemedicine centers. Technology, transfer, inpatient, and procedure-related costs were included. A sensitivity analysis was performed for worst and best scenarios of costs, revenues, and savings. A comparison with Avera e-Emergency (Sioux Falls, SD) Telemedicine program, involving 85 rural hospitals in 7 states, is provided (13% transfer avoidance).

Results

Of 784,947 screened patients, 8,448 had STEMI (1.08%); 3,911 (46.3%) were urgently reperfused, 3,049 (78%) with PPCI. Time to Telemedicine Diagnosis was 3 min. With efficient triage, costs for non-AMI patients was controlled. LATIN expenses, including for IT and experts, were $272, and for transfer and indirect care, $1,068. Net savings/patient were $796. Savings, till date, range between $187.4 million and $62.4 million (Best scenario −30% transfer avoidance; Worse scenario −10% transfer avoidance).

Conclusions

Longitudinal analysis firms the trend of enormous cost savings with LATIN. Telemedicine avoids unnecessary transfers and hospitalization and it is a cost-effective strategy for population-based AMI programs.

P1741Hitting the wall in converting diagnosed ST-elevation myocardial infarction patients to treating them: a humbling analysis from LATIN telemedicine

Background

The behemoth telemedicine program, Latin America Telemedicine Infarct Network (LATIN) has exponentially grown in 4 countries in Central and South America. It has provided AMI coverage to >100 million patients and it has contributed to transforming AMI care in the continent by its “halo” effect. We continue our meticulous search in evaluating the impact of LATIN and in doing so, we have confronted a sobering reality.

Purpose

To make continued improvements in population-based AMI management, the continued success of the initiative requires participation from healthcare policy makers, health economists, and payers.

Methods

LATIN was created as a hub and spoke model to hugely increase access (>100 million population coverage) to quality AMI treatment primarily with short door to balloon time (D2B) PCI. Innovative telemedicine platforms were created and networked at all 350 centers that were located in small clinics and primary health centers in poor sections of the countries (spokes) and at 24/7 PCI capable institutions (hubs). Remote cardiologists, located in 3 central locations, provided immediate EKG diagnosis (time to telemedicine diagnosis, TTD <3.5 minutes) and they provided expert guidance for the entire STEMI process, Door in Door Out (DIDO), and transport times (TT). LATIN performance metrics, under its strict control, and including process metrics at the hubs, spokes, and at the command telemedicine sites, were measured and plotted. The macroeconomic variables of insurance approvals, ambulance structure, and availability of ICU beds were determined and incorporated into performance variables of the LATIN program.

Results

784,395 patients were screened at 350 LATIN centers (Brazil 143, Colombia 118, Mexico 82, Argentina 7). With expanded reach, 8,440 (1.08%) patients were diagnosed and 3,924 (46.5%) urgently reperfused, including 3,048 (77.7%) with PCI. Time to Telemedicine Diagnosis (TTD) was 3 min, tele-accuracy 98.9%, D2B 51 min, and in-hospital mortality 5.2%. Over 4 years of operation, the proportion of reperfused STEMI patients has ranged between 41–48% - the major reasons for non-treatment were insurance, lack of ICU beds and delayed presentation.

Conclusions

Sustained improvements, as a result of stringent QA processes and continuous education, have resulted in reduced D2B, TTD, DIDO, TT, and in overall mortality. However, LATIN remains constrained with a large proportion of patients that are diagnosed but not treated, largely because of payer denials. Although this metric is showing improvement from broad dissemination of LATIN benefits, further gains from LATIN will result mainly from improved reimbursements.

Evolvability meets biogeography: evolutionary potential decreases at high and low environmental favourability

Understanding and forecasting the effects of environmental change on wild populations requires knowledge on a critical question: do populations have the ability to evolve in response to that change? However, our knowledge on how evolution works in wild conditions under different environmental circumstances is extremely limited. We investigated how environmental variation influences the evolutionary potential of phenotypic traits. We used published data to collect or calculate 135 estimates of evolvability of morphological traits of European wild bird populations. We characterized the environmental favourability of each population throughout the species' breeding distribution. Our results suggest that the evolutionary potential of morphological traits decreases as environmental favourability becomes high or low. Strong environmental selection pressures and high intra-specific competition may reduce species' evolutionary potential in low- and high- favourability areas, respectively. This suggests that species may be least able to adapt to new climate conditions at their range margins and at the centre. Our results underscore the need to consider the evolutionary potential of populations when studying the drivers of species distributions, particularly when predicting the effects of environmental change. We discuss the utility of integrating evolutionary dynamics into a biogeographical perspective to understand how environmental variation shapes evolutionary patterns. This approach would also produce more reliable predictions about the effect of environmental change on population persistence and therefore on biodiversity.

Bone marrow failure and extramedullary hematopoiesis in McCune-Albright syndrome

In fibrous dysplasia/McCune-Albright syndrome (FD/MAS), bone and bone marrow are, to varying degrees, replaced by fibro-osseous tissue typically devoid of hematopoietic marrow. Despite the extensive marrow replacement in severely affected patients, bone marrow failure is not commonly associated with FD/MAS. We present a 14-year-old girl with FD/MAS, who developed pancytopenia and extramedullary hematopoiesis (EMH) with no identified cause, in the setting of iatrogenic thyrotoxicosis and hyperparathyroidism. Pancytopenia, requiring monthly blood transfusions, persisted despite multiple strategies to correct these endocrinopathies. Due to worsening painful splenomegaly, likely as a result of sequestration, splenectomy was performed. Following splenectomy, pancytopenia resolved and patient has since been transfusion-independent. We report the first detailed case of bone marrow failure and EMH in FD/MAS. The etiology of marrow failure is likely multifactorial and related to the loss of marrow reserve due to extensive polyostotic FD, exacerbated by iatrogenic thyrotoxicosis and hyperparathyroidism. Mini Abstract: A patient with fibrous dysplasia developed bone marrow failure and extramedullary hematopoiesis. The etiology likely involved loss of hematopoetic marrow space and uncontrolled endocrinopathies. Splenectomy was therapeutic.

Behavioural innovation and cultural transmission of communication signal in black howler monkeys

Social traditions based on communication signals are widespread in birds, cetaceans and humans, but surprisingly rare in nonhuman primates known for having genetically-determined vocal repertoires. This study presents the first description of a singular case of behaviour associated with calling (placing a hand in front of the mouth while vocalizing: HFM) in black howler monkeys. We showed, first, that HFM was found only in a subset of the groups observed, at the same geographical location, and was age- and sex-specific. There was an audience effect on HFM, with highest rates when a neighbouring group was visible. HFM was non-randomly combined with audio-visual signals and always performed while roaring. High HFM rates triggered more vocal responses from group members and male neighbours, and HFM signalers temporally synchronized their behaviour in a predictable way. Finally, the positioning of the hand systematically modified the call's auditory structure. Altogether these results support the idea that HFM is an innovated, culturally transmitted communication signal that may play a role in inter-group competition and intra-group cohesion. This study opens new lines of research about how nonhuman primates developed strategies to overcome their constraints in acoustic plasticity very early in the primate lineage.

The role of visceral and subcutaneous adipose tissue fatty acid composition in liver pathophysiology associated with NAFLD

Visceral adiposity is associated with type-2-diabetes, inflammation, dyslipidemia and non-alcoholic fatty liver disease (NAFLD), whereas subcutaneous adiposity is not. We hypothesized that the link between visceral adiposity and liver pathophysiology involves inherent or diet-derived differences between visceral and subcutaneous adipose tissue to store and mobilize saturated fatty acids. The goal of the present study was to characterize the fatty acid composition of adipose tissue triglyceride and portal vein fatty acids in relation to indices of liver dysregulation. For 8 weeks rats had free access to control (CON; 12.9% corn/safflower oil; 3.6 Kcal/g), high saturated fat (SAT; 45.2% cocoa butter; 4.5 Kcal/g) or high polyunsaturated fat (PUFA; 45.2% safflower oil; 4.5 Kcal/g) diets. Outcome measures included glucose tolerance, visceral and subcutaneous adipose tissue triglyceride, liver phospholipids and plasma (portal and systemic) free fatty acid composition, indices of inflammation and endoplasmic reticulum stress in the liver and adipose tissue depots and circulating adipo/cytokines. Hepatic triglycerides were significantly increased in both high fat diet groups compared to control and were significantly higher in PUFA compared to SAT. Although glucose tolerance was not different among diet groups, SAT increased markers of inflammation and ER stress in the liver and both adipose tissue depots. Fatty acid composition did not differ among adipose depots or portal blood in any dietary group. Overall, these data suggest that diets enriched in saturated fatty acids are associated with liver inflammation, ER stress and injury, but that any link between visceral adipose tissue and these liver indices does not involve selective changes to fatty acid composition in this depot or the portal vein.

Efficacy of pimobendan in the prevention of congestive heart failure or sudden death in Doberman Pinschers with preclinical dilated cardiomyopathy (the PROTECT Study)

BACKGROUND

The benefit of pimobendan in delaying the progression of preclinical dilated cardiomyopathy (DCM) in Dobermans is not reported.

HYPOTHESIS

That chronic oral administration of pimobendan to Dobermans with preclinical DCM will delay the onset of CHF or sudden death and improve survival.

ANIMALS

Seventy-six client-owned Dobermans recruited at 10 centers in the UK and North America.

METHODS

The trial was a randomized, blinded, placebo-controlled, parallel group multicenter study. Dogs were allocated in a 1:1 ratio to receive pimobendan (Vetmedin capsules) or visually identical placebo. The composite primary endpoint was prospectively defined as either onset of CHF or sudden death. Time to death from all causes was a secondary endpoint.

RESULTS

The proportion of dogs reaching the primary endpoint was not significantly different between groups (P = .1). The median time to the primary endpoint (onset of CHF or sudden death) was significantly longer in the pimobendan (718 days, IQR 441-1152 days) versus the placebo group (441 days, IQR 151-641 days) (log-rank P = 0.0088). The median survival time was significantly longer in the pimobendan (623 days, IQR 491-1531 days) versus the placebo group (466 days, IQR 236-710 days) (log-rank P = .034).

CONCLUSION AND CLINICAL IMPORTANCE

The administration of pimobendan to Dobermans with preclinical DCM prolongs the time to the onset of clinical signs and extends survival. Treatment of dogs in the preclinical phase of this common cardiovascular disorder with pimobendan can lead to improved outcome.

Social and hormonal mechanisms underlying male reproductive strategies in black howler monkeys (Alouatta pigra)

We investigated the social and hormonal mechanisms underlying male reproductive strategies in two multimale-multifemale groups of black howler monkeys (Alouatta pigra) during a 14-month study in Palenque National Park, Mexico. Fecal glucocorticoid (fGC) and androgen (fA) levels were analyzed for 343 fecal samples collected from 14 males during their presence in the study groups. Neither immigrating males nor resident males that remained in the group had elevated fGC and fA levels during 11 observed male migration events, suggesting that competition over group membership was not associated with variation in the fecal hormonal levels of males. Instead, fGC and fA levels were significantly higher in males who maintained a central position in the group and had almost exclusive access to fertile females than in other resident males. These "central" males were responsible for maintaining close spatial associations and cultivating strong affiliative relationships with cycling, sexually active females but not with noncycling, sexually inactive females. "Noncentral" males did not form strong social relationships with either cycling or noncycling females and had no or very few mating opportunities. Our findings suggest that male black howler monkeys compete nonaggressively by fostering relationships with cycling females and that the elevated fGC levels of central males may be indicative of the social challenges involved in their indirect competition.

Preoperative Risk Factors Associated With Mortality in Lung Biopsy Patients With Interstitial Lung Disease

The objective of this study was to evaluate the risk factors associated with mortality in interstitial lung disease patients. We performed a retrospective study of 722 consecutive patients submitted for lung biopsy during the 1986-1990 period. Twenty-two (3%) died within the 30 days following surgery. Forty-four patients who survived after the surgery for the same time span were randomly chosen as control group. Dyspnea at rest was present in 18/44 of surviving group (SG) and in 18/22 of the nonsurviving group (NSG) (OR 6.5, 95% CI 1.8-22.4,p = .001). Systemic diseases (i.e., diabetes, systemic arterial hypertension)were mainly present in the NSG (OR 7.2, 95% CI 2.3-22.8, p < .001). The SG displayed significantly less respiratory insufficiency with a PaO2 of 52.2 + 8.4 versus 38.5 i 9.4 mm Hg, and PaCO2 of 28.8 i 4.5 versus 38.5 +/- 9.2 mm Hg, respectively (p < .001). Likewise, the SG exhibited a PaCO2/PaO2 ratio of 0.5 - 0.1, while in the NSG it was of 1 +/- 0.4 (p < .001), showing a sensitivity of 84% and specificity of 93% for mortality. Multiple logistic regression analysis for these variables showed that log likelihood was still significant for PaCO2 > 34 mm Hg, PaO2 <48 mm Hg, and comorbid diseases. Logistic regression analysis of these three variables showed the greatest sensitivity and specificity (84 and 750/0,respectively) for prediction of mortality. However, the strongest association was found when PaCO2/PaO2 ratio was analyzed alone (OR 21,073,CI 95% 28-15,946,357, p < .005). These data suggest that PaCO2/PaO2 ratio appears to be a predictor of mortality in this subset of patients. Its prospective use has reduced early mortality after surgery less than 1% in the last decade.

Promoter variants in tissue inhibitor of metalloproteinase-3 (TIMP-3) protect against susceptibility in pigeon breeders' disease

BACKGROUND

Tissue inhibitors of metalloproteinases (TIMPs) play a major role in extracellular matrix turnover in the lung. However, in chronic lung disorders such as idiopathic pulmonary fibrosis (IPF) and pigeon breeders' disease (PBD), TIMPs may promote an adverse non-degradative environment. We hypothesised that polymorphisms in TIMP-3 could affect susceptibility to IPF and PBD.

METHODS

Two promoter variants, -915A>G and -1296T>C, were genotyped in 323 healthy subjects, 94 subjects with IPF, 115 with PBD, and 90 exposed to avian antigen but without PBD. The severity of fibrosis in lung tissue and the clinical outcome after 1 year was determined in the PBD group.

RESULTS

The variants did not influence susceptibility to IPF, but the rare alleles of both variants appeared to be protective against susceptibility to PBD (odds ratio (OR) for carriage of at least one rare allele from either variant 0.48, 95% CI 0.30 to 0.76, p = 0.002). Haplotype analysis of positions -915 and -1296 estimated four haplotypes: *A*T, *G*T, *A*C and *G*C, respectively. Their frequencies differed overall between subjects with PBD and healthy subjects (p = 0.0049) and this was attributable primarily to the *G*C haplotype (OR 0.53, 95% CI 0.36 to 0.77, p = 0.001). The severity of fibrosis correlated with poorer outcome in the PBD group (r = 0.73, p<0.01) but no relationship was seen between the *G*C haplotype and outcome or fibrosis. However, PBD subjects with the *G*C haplotype did have proportionally fewer lymphocytes in their bronchoalveolar fluid than those with the common *A*T haplotype (p = 0.029).

CONCLUSIONS

TIMP-3 variants appear to contribute to susceptibility to PBD. This may be through the inflammatory reaction rather than the fibrotic reaction.

Correlates of helminth community in the red-legged partridge (Alectoris rufa L.) in Spain

Between 1992 and 1996, 587 wild red-legged partridges (Alectoris rufa) from 16 Spanish provinces were examined to study the variations of helminth communities in this game species across a broad geographical area. The survey revealed 13 species of helminth parasites. Dicrocoelium sp.. Rhabdometra nigropunctata, and Cheilospirura gruweli were the most common species, whereas Raillietina bolivari, Choanotaenia infundibulum, Tetrameres sp., and Capillaria anatis were the most rare. Subulura suctoria, Heterakis gallinarum, Heterakis tenuicaudata, Capillaria contorta, Trichostrongylus tenuis, and Raillietina tetragona occurred with intermediate frequencies. The abundance of C. gruweli, S. suctoria, H. tenuicaudata, T. tenuis, and R. tetragona was inversely correlated to latitude and directly correlated to yearly mean temperature, whereas the abundance of Dicrocoelium sp. was directly correlated to latitude and inversely correlated to yearly mean temperature. The abundance of R. tetragona was inversely correlated to latitude and yearly mean humidity. The number of helminths per partridge and the number of helminth species per partridge were lower in young birds than in adults. Partridge body condition was inversely correlated to abundance of C. contorta. Richer infracommunities were linked to richer component communities. At the infracommunity level, total number of helminths per partridge and number of helminth species per partridge were inversely correlated to latitude and directly correlated to yearly mean temperature. At the component community level, both species richness and diversity (Simpson's index) were inversely correlated to latitude and directly correlated to mean temperature. Across the broad geographical range of the study area, the helminth parasite communities of red-legged partridges had marked geographical variation in their structure. Our results suggest that this variation is determined by the distribution of both intermediate and definitive hosts. We discuss the implications of this variation for the hypothesis that supplementary releases of captive-bred partridges for sport hunting can affect the helminth fauna of wild red-legged partridges.

Ectoparasite ticks and chewing lice of red-legged partridge, Alectoris rufa, in Spain

During the 1992-1993 and 1993-1994 shooting seasons, 212 wild red-legged partridge, Alectoris rufa (Galliformes: Phaisanide) were captured in 18 Spanish provinces and examined for chewing lice and ticks. Three tick species and six species of chewing lice were found. Ticks (Acari: Ixodidae) Haemaphysalis punctata Canestrini & Fanzago, Hyalomma lusitanicum Koch and Ixodes frontalis Panzer were found at the lowest prevalence (1.4% overall tick prevalence). The louse (Mallophaga) species, Goniodes dispar Burmeister (Goniodidae) (52.8%) and Cuclotogaster obscurior Hopkins (Philopteridae) (28.8%) were the most prevalent, while Goniocotes obscurus Giebel (Philopteridae) (10.8%), Menopon pallens Clay (Menoponidae) (7.5%) and Menacanthus lyali Rodriguez et al. (Menoponidae) (3.3%) were found at medium to low prevalence. Columbicola columbae columbae Linnaeus (Philopteridae) was found at the lowest prevalence (0.5%). The intensity of C. obscurior and overall intensity of all lice species were directly related to the environmental mean temperature and the Normalized Difference Vegetation Index (NDVI), whereas intensity of G. dispar was directly related to NDVI only. The intensity of G. dispar, C. obscurior, all louse intensity, and louse species richness were higher in male than female birds. Intensity of each louse species, all louse intensity and louse species richness were inversely associated with the nutritional index. No relationship was observed between bird age and louse intensity or species richness.

Social medicine then and now: lessons from Latin America

The accomplishments of Latin American social medicine remain little known in the English-speaking world. In Latin America, social medicine differs from public health in its definitions of populations and social institutions, its dialectic vision of "health-illness," and its stance on causal inference. A "golden age" occurred during the 1930s, when Salvador Allende, a pathologist and future president of Chile, played a key role. Later influences included the Cuban revolution, the failed peaceful transition to socialism in Chile, the Nicaraguan revolution, liberation theology, and empowerment strategies in education. Most of the leaders of Latin American social medicine have experienced political repression, partly because they have tried to combine theory and political practice--a combination known as "praxis." Theoretic debates in social medicine take their bearings from historical materialism and recent trends in European philosophy. Methodologically, differing historical, quantitative, and qualitative approaches aim to avoid perceived problems of positivism and reductionism in traditional public health and clinical methods. Key themes emphasize the effects of broad social policies on health and health care; the social determinants of illness and death; the relationships between work, reproduction, and the environment; and the impact of violence and trauma.

Bioactive acridone alkaloids from Swinglea glutinosa

A new prenylated acridone alkaloid, 1,3,5-trihydroxy-2,8-bis(3-methylbut-2-enyl)-10-methyl-9-acridone (1), was isolated from the stembark of Swinglea glutinosa, along with three known acridone alkaloids, 5-hydroxynoracronycine (2), 1,3,5-trihydroxy-4-methoxy-2-(3-methylbut-2-enyl)-10-methyl-9-acridone (3), and 1,3,5-trihydroxy-4-methoxy-10-methylacridone (4). The isolated alkaloids were assessed in vitro against chloroquine-sensitive and -resistant Plasmodium falciparum strains and for cytotoxicity using HeLa cells.

Social medicine in Latin America: productivity and dangers facing the major national groups

There is little knowledge about Latin American social medicine in the English-speaking world. Social medicine groups exist in Argentina, Brazil, Chile, Colombia, Cuba, Ecuador, and Mexico. Dictatorships have created political and economic conditions which are more adverse in some countries than others; in certain instances, practitioners of social medicine have faced unemployment, arrest, torture, exile, and death. Social medicine groups have focused on the social determinants of illness and early death, the effects of social policies such as privatisation and public sector cutbacks, occupational and environmental causes of illness, critical epidemiology, mental health effects of political trauma, the impact of gender, and collaborations with local communities, labour organisations, and indigenous people. The groups' achievements and financial survival have varied, depending partly on the national context. Active professional associations have developed, both nationally and internationally. Several groups have achieved publication in journals and books, despite financial and technical difficulties that might be lessened through a new initiative sponsored by the US National Library of Medicine. The conceptual orientation and research efforts of these groups have tended to challenge current relations of economic and political power. Despite its dangers, Latin American social medicine has emerged as a productive field of work, whose findings have become pertinent throughout the world.

Major histocompatibility complex and tumor necrosis factor-alpha polymorphisms in pigeon breeder's disease

Pigeon breeders disease (PBD) is caused by the exposure of a susceptible host to avian antigens. However, genetic factors determining individual predisposition are unknown. In this work, polymorphisms of the major histocompatibility complex (MHC) class II alleles and tumor necrosis factor alpha (TNF-alpha) promoter were evaluated in 44 patients with PBD, 99 healthy unrelated controls (HC), and 50 exposed but asymptomatic subjects (EAS). MHC typing was performed by PCR-specific sequence oligonucleotide analysis, and TNF-alpha polymorphism at -238 and -308 positions by amplification refractory mutation system-PCR. PBD patients showed a significant increase of the alleles HLA-DRB1*1305 (p < 0.001, OR = 15.4, 95% CI = 3.18-102.6 [HC], and OR = 17.05, 95% CI = 2.25-357.8 [EAS]) and HLA-DQB1*0501 (p < 0.05, OR = 2.93, 95% CI = 1.21-7.15 [HC], and OR = 2.96, 95% CI = 1.0-9.14 [EAS]). A decrease of HLA-DRB1*0802 was also noticed in patients when compared with both control groups (p < 0.05). Haplotype analysis revealed an increase of DRB1*1305-DQB1*0301 and a decrease of DRB1*0802-DQB1*0402. PBD patients had an increased frequency of TNF-2(-)(308) compared with both control groups (p < 0.05). Patients exhibiting the TNF-2(-)(308) allele were younger (33.9 +/- 14.6 versus 44.2 +/- 10.4 yr; p < 0.05), and displayed more lymphocytes in their bronchoalveolar lavages (88.0 +/- 12.1 versus 68.9 +/- 17.2; p < 0.05). These results suggest that genetic factors located within the MHC region contribute to the development of PBD.

[Floristic composition and structure of a premontane moist forest in Central Valley of Costa Rica]

The floristic composition and structure of a premontane moist forest remnant were studied in the El Rodeo Protected Zone, Central Valley of Costa Rica. Three one-hectare plots were established in the non-disturbed forest, and all trees with a diameter at breast height (dbh) of 10 cm or greater were marked, measured and identified. The plots were located within a radius of 500 m from each other. A total of 106 tree species were recorded in the three plots. Average values: species richness 69.6 species ha-1, abundance 509 individuals ha-1, basal area 36.35 m2 ha-1. Total diversity was 3.54 (Shannon Index, H'), and the species similarity among the plots ranged between S = 0.68 and 0.70 (Sørensen Similarity Index). Most tree species are represented by few individuals (five or less). There is a lack of emergent trees and arborescent palms in the forest canopy. According to the Familial Importance Value, Moraceae, followed by Fabaceae, Lauraceae, and Sapotaceae, largely dominates this forest. Pseudolmedia oxyphillaria (Moraceae) is the dominant species (Importance Value Index), accounting for 25% of all the marked trees in the plots, followed by Clarisia racemosa (Moraceae), Heisteria concinna (Olacaceae), and Brosimum alicastrum (Moraceae). The size class distributions were similar among plots, and in general followed the expected J-inverted shape. Differences in tree abundance, floristic composition, and spatial distribution of some species among the plots suggest heterogeneity of this ecosystem's arborescent vegetation. Moreover, it is an important natural reservoir for the conservation of rare and endangered tree species in a national level. Using these results as a baseline, this study should start a long term monitoring of the structure and composition of this very reduced and fragmented ecosystem.

Effect of the dietary supplementation of fructooligosaccharides and Bifidobacterium longum to early-weaned pigs on performance and fecal bacterial populations

Two experiments were conducted to evaluate the effect of administration of fructooligosaccharides (FOS) and Bifidobacterium longumon growth performance and fecal bacterial populations in pigs weaned at 18 d of age. In exp. 1, two groups of 20 pigs each were fed diets containing 0 or 0.5% FOS for 21 d. On days 1 and 3, pigs receiving FOS were administered an oral dose of 1010 B. longumcells. During week 1, average daily gain was higher and feed efficiency was improved (P < 0.05) in pigs fed FOS and bifidobacteria relative to the control. On day 7, supplemented pigs had reduced numbers of total anaerobes and clostridia, and increased numbers of bifidobacteria in faeces (P < 0.05). In exp. 2, 80 pigs were divided into four groups of 20 animals each in a 2 x 2 factorial design. Main effects included FOS supplementation (0 or 0.5% of diet) and B. longum supplementation (0 or 107 cells per gram feed). FOS supplementation reduced growth while B. longum supplementation increased growth (P< 0.05). On days 12 and 19, serum insulin-like growth factor I (IGF-I) was reduced with FOS supplementation and increased with B. longum supplementation (P < 0.05). It was concluded that the continuous administration of bifidobacteria provided a beneficial effect on growth parameters studied in this experiment. Key words: Pigs, fructooligosaccharides, bifidobacteria, Bifidobacterium longum, performance

Feeding and general activity patterns of a howler monkey (Alouatta palliata) troop living in a forest fragment at Los Tuxtlas, Mexico

The feeding behavior and general activity patterns of a howler monkey troop living in a 3.6 ha forest fragment were studied at Los Tuxtlas, Mexico, for an annual cycle. Monthly samples of their feeding behavior indicated that they used 52 species of 24 plant families as sources of food. Of these, 67% were trees, which accounted for 96% of total feeding time recorded. Ten species of Moraceae, Cecropiaceae, Anacrdiaceae. and Sapotaceae contributed to 70% of the trees used and to almost 90% of feeding time. The number of plant species used per monthly record varied from 7 to 31 with an average of 19.9 species. Young leaves and ripe fruit were the principal items in the monthly diet of howlers and average percent of time spent consuming these plant parts was 46.7% and 34.8%, respectively. The use of tree species was found to be associated to their importance value and to their pattern of spatial dispersal in the study site. Availability of young leaves was fairly constant from month to month, but it presented a seasonal pattern, and there was a significantly lower number of tree species bearing ripe fruit through the year with brief pulses of production. The monthly activity pattern was found to be related to variations in the availability of young leaves and ripe fruit as well as to the values of the intermonthly overlap in plant species used. Resting and feeding presented a bimodal pattern of occurrence throughout the day that seemed to be related to variations in maximum ambient temperatures. Results are discussed in light of the small size and shape of the forest fragment inhabited by the howler troop.

Tropical rain forest fragmentation, howler monkeys (Alouatta palliata), and dung beetles at Los Tuxtlas, Mexico

In Neotropical rain forests, fresh mammal dung, especially that of howler monkeys, constitutes an important resource used by dung beetles as food and for oviposition and further feeding by their larvae. Tropical rain forest destruction, fragmentation, and subsequent isolation causing reductions in numbers of and the disappearance of howler monkeys may result in decreasing numbers of dung beetles, but this has not been documented. In this study, we present information on the presence of howlers and dung beetles in 38 isolated forest fragments and 15 agricultural habitats. Howler monkeys were censused by visual means, while dung beetles were sampled with traps baited with a mixture of howler, cow, horse, and dog dung. Results indicated that loss of area and isolation of forest fragments result in significant decrements in howlers and dung beetles. However, dung beetle abundance was found to be closely related to the presence of howler monkeys at the sites and habitats investigated. Scenarios of land management designed to reduce isolation among forest fragments may help sustain populations of howler monkeys and dung beetles, which may have positive consequences for rain forest regeneration.

Increase of lung neutrophils in hypersensitivity pneumonitis is associated with lung fibrosis

Hypersensitivity pneumonitis (HP) is characterized by a T-cell-mediated alveolitis, and the putative role of other inflammatory cells in its pathogenesis remains unclear. In this study we determined whether increased quantities of neutrophils were present in HP lungs, and if they were positive for gelatinase B and collagenase-2. Fifteen nonsmoking patients with subacute/chronic active HP were included. Lung samples were analyzed using myeloperoxidase antibody, and neutrophil/total cell ratio was evaluated by digital processing. All HP tissue samples exhibited variable quantities of neutrophils located inside vessels, and in the interstitial and alveolar spaces. Lung neutrophil percentage ranged from 0.7% to 4.8% (2.1 +/- 1.4%). There was a positive correlation between the percentage of lung neutrophils and the percentage of lung fibrosis (r = 0.6, p < 0.02). Tissue neutrophils showed intense immunoreactive collagenase-2 and gelatinase B staining. Additionally, gelatinolytic activities corresponding to progelatinases A and B and their activated forms, were several-fold increased in the bronchoalveolar lavage fluid (BALF) from patients with HP as compared with control subjects. These findings suggest that in HP lungs there is a persistent traffic of neutrophils loaded with gelatinase B and collagenase-2 that may play a role in the lung damage and in the fibrotic response.

HIV infection and patterns of risk among women drug injectors and crack users in low and high sero-prevalence sites

As AIDS cases among US women continue to increase, a better understanding of women's behavioural risk patterns is needed to inform intervention efforts. Data were from 2,945 women drug injectors and crack users. Statistical analyses compared sociodemographic variables, lifetime behavioural risk patterns, HIV sero-prevalence and history of sexually transmitted diseases, and determined predictors of HIV infection separately in 16 low and four high sero-prevalence sites. Based on risk patterns, four behaviourally-defined sub-groups were constructed, and rates of HIV sero-prevalence were compared. In comparisons between low and high sero-prevalence sites, there were significant differences on most variables examined, and in the relative importance of the sociodemographic characteristics and risk patterns predicting HIV. Drug injection and sex exchange were each independent, significant, behavioural predictors of infection, with no significant difference between the odds ratios attributed to each predictor. HIV sero-prevalence was significantly different among four sub-groups. Interventions must be tailored to address observed differences among women in low and high sero-prevalence sites. Injection drug use and exchanging sex each play a major role in the transmission of HIV infection to US women. Prevention efforts targeted at women should address differences in behavioural risk patterns. Aggressive and innovative interventions are needed for women who exchange sex. AIDS research must investigate how socioeconomic factors impact women's risk for HIV infection.

Isolation and evaluation of immunological adjuvant activities of saponins from Polygala senega L

We have identified saponins in the root of Polygala senega L., a plant indigenous to the Canadian prairies, which display immunopotentiation activity to protein and viral antigens. By two-step extraction and hemolytic activity-guided fractionation by silica flush chromatography six saponin fractions were generated and their HPLC profiles determined. Two dominant fractions, designated as PS-1 and PS-2, were tested for adjuvant activity in mice immunized with ovalbumin, and hens immunized with rotavirus. The resulting adjuvant activity was compared with that of Quil A saponin. The P. senega saponins increased specific antibody levels to the antigens, in both mice and hens. In mice, there was a preferential increase of the IgG2a subclass, and upon in vitro secondary antigen stimulation, high IL-2 and IFN-gamma levels were observed in spleen cell cultures from P. senega saponins-immunized animals. The saponins were tested for their toxicity by lethality in mice and were found to be less toxic at the same dose than their counterpart Quil A. The results of this study indicated the potential of P. senega saponins as vaccine adjuvants to increase specific immune responses.

Effect of segregated early weaning on postweaning small intestinal development in pigs

The effect of segregated early weaning (SEW) on postweaning small intestinal development was investigated in SEW and control (CON) pigs. Small intestines were collected from a total of 15 pigs killed at 11 (preweaning), 15 (3 d postweaning), and 34 d of age. At 3 d postweaning, the SEW and CON pigs had shorter villi (P<.01), deeper crypts (P<.01), and reduced (P<.01) ratios of villus height:crypt depth (V:C) compared with preweaning. Weaning also reduced specific activities of lactase (P<.01) in duodenum and ileum and alkaline phosphatase (ALP) (P<.05) in duodenum and jejunum. Sucrase activity in the three regions of the small intestine marginally decreased in both groups at 3 d postweaning. The mucosal protein:DNA ratio in duodenum and jejunum increased (P<.05) in SEW and CON pigs at 3 d postweaning compared with preweaning pigs. The SEW and CON treatments resulted in differences in postweaning gut development. At 15 d of age in SEW pigs, the mucosal protein:DNA ratio in duodenum and jejunum were 20 and 25.5% (P<.05) less, respectively, than those in CON pigs. However, at 34 d, these ratios in duodenum, jejunum, and ileum were 43.5 (P<.05), 24.3, and 32.9% (P<.05) greater, respectively, in SEW pigs than in CON pigs. Longer villi, shorter crypts (P<.01), and higher V:C ratios (P<.01) in jejunum and ileum were observed in SEW pigs vs CON pigs at 34 d of age. The specific activities of lactase in duodenum (P<.01) and jejunum (P<.05) and of ALP in duodenum (P<.01) were higher in SEW pigs. Sucrase activity in duodenum, jejunum, and ileum was 21.7, 46.3 (P<.05), and 11.2% greater in SEW pigs at 34 d of age. These results demonstrate differences in postweaning gut development between SEW and CON pigs. Furthermore, the number of intraepithelial lymphocytes in jejunum was greater (P<.001) in 34-d-old SEW pigs compared with CON pigs. Microscopy revealed a thick mucus coating over epithelial cells in the ileum of 34-d-old CON pigs that was not apparent in the SEW pigs. These observations are consistent with reduced pathogen exposure associated with SEW. We suggest that segregated early weaning advances postweaning gut maturation, which is consistent with improved growth and feed efficiency observed in SEW pigs.

Effect of administration of oat beta-glucan on immune parameters of healthy and immunosuppressed beef steers

In order to assess the effect of oat beta-glucan (ObetaG) administration on immune parameters of beef steers, 3 experiments were carried out. In experiment 1, the in vitro effect of ObetaG on the proliferation of blood lymphocytes, with or without the presence of dexamethasone (DXM), was evaluated. In experiment 2, groups of 12 healthy steers were administered ObetaG or saline solution and immunized with ovalbumin (OVA). Immune parameters studied included IgG antibody levels to OVA, proliferation responses of blood lymphocytes to OVA, and blood leukocyte differential cell counts. For experiment 3, groups of 10 steers were treated with ObetaG and DXM, DXM only, or saline solution, and immunized with OVA and keyhole limpet hemocyanin (KLH). Serum antibody responses to OVA and KLH, serum IgG concentration levels, blastogenic responses of blood lymphocytes to OVA and KLH, differential blood leukocyte numbers, and iron and zinc concentration in serum were tested to evaluate the effect of ObetaG to overcome immunosuppression. The in vitro treatment of naive blood lymphocytes with ObetaG did not increase their ability to proliferate; however, when ObetaG was added to cultures of DXM-treated lymphocytes, a significant (P < 0.05 to P < 0.001) reversion of the immunosuppressive effect of DXM occurred. Administration of ObetaG to clinically healthy steers did not induce significant changes on any of the immune parameters studied. The administration of ObetaG to DXM-treated steers provoked, on Day 25, a significant increase in IgG anti-OVA (P < 0.01) and anti-KLH (P < 0.05) responses vs the DXM only group. On Day 25, the specific proliferation responses of lymphocytes, to both OVA and KLH, were significantly increased (P < 0.05) in ObetaG+DXM group compared to DXM group. On Day 4, a significant increase in the number of leukocytes (P < 0.01) and neutrophils (P < 0.001), and a significant decrease in the number of monocytes (P < 0.05) were observed in the group treated with DXM only compared to ObetaG+DXM group. No significant differences were observed in iron and zinc concentration between ObetaG+DXM and DXM groups. These results indicated that ObetaG did not influence immune responses of naive cells in vitro or of healthy steers in vivo; however, when cells or animals were treated with DXM, ObetaG significantly restored some of the specific and non-specific immune parameters studied.

The optokinetic cervico reflex during simulated helicopter flight

INTRODUCTION

The optokinetic cervico reflex (OKCR) is a recently hypothesized, visually driven reflex that serves to stabilize the image of the external horizon on the retina during roll maneuvers in high-performance aircraft. Although reported anecdotally, head tilt during helicopter flight has not been studied formally. Such research is required to determine the full impact and significance that it may have on the flying performance of a rotary-wing aviator.

OBJECTIVE

The aim of this study was to investigate the relationship between horizon position and the perception of orientation and, thus, to generate vital information to assess whether OKCR plays an important role in spatial disorientation.

HYPOTHESIS

Pilots of rotary-wing aircraft will exhibit the OKCR.

METHODS

A UH-60 flight simulator study, with 20 volunteer pilots participating, was performed to examine the effects of this reflex during day flight and during flight with night vision goggles (NVGs).

RESULTS

The results confirm that the OKCR occurs during simulated helicopter flight, both with and without NVGs. As with previous studies, head roll increased during flight under visual meteorological conditions in relation to an increasing aircraft roll angle up to a maximum sustainable level and then remained constant. Head roll did not occur during flight under instrument meteorological conditions.

CONCLUSION

The presence of the OKCR will impact rotary-wing operations. Various aspects are discussed, and recommendations are made for future research.

Immunomodulatory effects of oat beta-glucan administered intragastrically or parenterally on mice infected with Eimeria vermiformis

The immunostimulatory effect of intragastrically or parenterally administered beta-(1-->3; 1-->4) glucan, extracted from oats (ObetaG), on disease resistance to Eimeria vermiformis was studied in C57BL/6 mice. Multiple administrations of ObetaG by intragastric or subcutaneous routes reduced fecal oocyst shedding compared to the non-treated control group. The administration of ObetaG by subcutaneous route resulted in higher levels of total serum immunoglobulins and antigen (sporozoite and merozoite)-specific immunoglobulins as compared with the non-treated group. To evaluate the effect of a single subcutaneous dose, groups of mice were treated with ObetaG 2 days before E. vermiformis infection, at the time of infection and at 2 or 6 days after infection. From day 11 post-infection the oocyst discharge was significantly diminished (P<0.05-0.01) in the ObetaG-treated groups, except in those treated 6 days after infection, as compared to the non-treated control group. The proliferative responses to E. vermiformis sporozoite antigen of lymphocytes isolated from the spleen were significantly increased (P<0.05) when ObetaG was administered 2 days before or at the time of E. vermiformis infection. Lymphocyte proliferative responses to merozoite antigen were not influenced by treatment. In conclusion, ObetaG appeared to up-regulate immune mechanisms and provide enhanced resistance against eimerian coccidiosis in mice.

An evaluation of the British Army spatial disorientation sortie in U.S. Army aviation

BACKGROUND

Following didactic instruction, most aircrew are able to experience some of the disorienting illusions and limitations of the orientation senses in a variety of ground-based devices. In order to reinforce instruction in spatial disorientation (SD) within the environment in which they operate, British Army Air Corps helicopter pilots also receive an airborne demonstration of the limitations of their orientation senses prior to rotary-wing instrument flight training. The objective of this assessment was to determine whether the SD demonstration sortie would be an effective adjunct in training aircrew in SD in the U.S. Army.

METHODS

There were 45 aviators and training personnel who experienced the sortie and gave their opinion in questionnaires.

RESULTS

The following conclusions were made: the maneuvers performed in the SD demonstration sortie, and the sortie overall, were extremely effective at demonstrating the limitations of the orientation senses; the SD sortie attracted a significantly higher rating in its effectiveness to train aviators in SD than all the currently available methods; the introduction of the sortie into the initial flight training syllabus would be a distinct enhancement to the SD training of aviators and associated personnel; and the introduction of the sortie into refresher training in field units would also be an advantage.

CONCLUSION

Other services are encouraged to consider this enhancement to the SD training of aviators.