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Some red-cockaded woodpecker (RCW) Dryobates borealis populations remain understudied. This is notable because management that incorporates population demographics and site characteristics may benefit RCW recovery. The Oakmulgee Ranger District of the Talladega National Forest (Alabama, USA) has no wiregrass Aristida stricta, small forest stand sizes, rolling topography, and contains an understudied RCW population. Our goal in the Oakmulgee was to characterize RCW habitat, possibly identify ways in which habitat differed from other regions, and estimate associations between habitat and reproductive output. We found that 70.2 and 92.5% of sampled stands met recovery standard thresholds for small and large pine basal area (BA) as defined in the United States Fish and Wildlife Service (USFWS) RCW Recovery Plan. While 74.6% of longleaf pine Pinus palustris-dominated stands met the threshold for overstory hardwood canopy composition, 60.0% of loblolly pine P. taeda-dominated stands did not. Few stands met the recommended percentage of herbaceous understory (19.8%) or recommended absence of hardwood midstory. A lower rate of partial brood loss was associated with a greater area of large pines (≥25.4 cm diameter at breast height; DBH), a smaller area of small pines (≥10 and

Extramedullary hematopoiesis (EMH) is a proliferation of hematopoietic tissue outside the bone marrow. The most affected areas are paravertebral ones. We report the case of a patient with homozygous Hb Lepore, not regularly transfused since the age of four years until the age of 29 years, when paravertebral heterotopic masses were first observed. After about 10 years she started reporting clinical signs suggestive of sinusitis. Computed tomography (CT) and Magnetic Resonance Imaging (MRI) showed heterotopic masses in the ethmoid and in the frontal sinuses. Involvement of the sinuses of the large facial area represents a rare localization of EMH. Various cases have been reported in patients with thalassemia intermedia, but no case has been reported with HbLepore. The diagnostic gold standard is MRI, which provides highly accurate and clear images. The treatment is based on hydroxyurea and/or an intensive transfusional regime and sometimes on surgery.

TheM-44 ejector (‘ejector‘) has proven to be a highly target-specific means of delivering toxicants to the exotic European red fox(Vulpes vulpes)in south-eastern Australia. Para-aminopropiophenone (PAPP) is a potent methaemoglobin (MetHb) forming compound in canids. A formulation of PAPP, dimethylsulphoxide (DMS0) and condensed milk was investigated as a new toxicant formulation for delivery by the ejector. Dosage of eight foxes in the laboratory with a sequential dose demonstrated that the formulation caused a dose-dependent and rapid elevation of MetHb. A strong inverse correlation between MetHb and oxyhaemoglobin concentrations was detected in each case. The symptoms of the toxicosis in the laboratory included progressive cyanosis, lethargy and then collapse when MetHb levels reached 56-76%. A polynomial model was a good fit for describing the relationship between sub-lethal doses of PAPP and the resulting peak MetHb levels. In a pen trial, an ejector was fitted with a bait and loaded with a standard dose of 226 mg PAPP in the same formulation and set at one end of a pen. After voluntarily triggering the ejector, all five foxes in this trial became progressively more lethargic and either lay prostrate or collapsed after 14-25 min, and death was confirmed after a mean of 43 min. We compared some clinical features of PAPP toxicosis with 15 cases of lethal sodium fluoroacetate (1080) poisoning using 0.5 mg kg-11080. PAPP produced a mean time to death that was 7.7 times faster than 1080, with the onset of first symptoms being 15 times faster. It was associated with much less activity prior to death and convulsions, spasms and paddling commonly associated with 1080 poisoning after collapse were not detected during PAPP toxicosis. We conclude that the PAPP formulation appears to be a rapidly acting and apparently humane lethal agent for fox control when used in conjunction with the ejector.

Predation of sheep and cattle by the dingo (Canis lupus dingo) is implicated in significant stock losses throughout much of mainland Australia. Leg-hold traps are commonly used for dingo control and ways are sought to improve the humaneness of these devices. We evaluated the performance of the tranquilliser trap device (TTD) attached to Victor Soft-Catch®traps for their ability to deliver a sedative and anxiolytic drug to trapped dingoes. A trapping programme was conducted in south-west Queensland where traps were set alternatively with a TTD containing either 800 mg of diazepam (drug TTD) or a placebo (placebo TTD). All TTDs included 20 mg of the bait marker iophenoxic acid (IPA) to ascertain dosing success. Each trap was fitted with an activity-monitoring data logger that recorded time of capture and subsequent dingo activity. In 41 out of 48 (85.4%) captures the TTD was ruptured and released its contents. No elevation in serum iodine levels above I mg ml-1resulting from the ingestion of IPA occurred in 8 out of 36 (22.2%) captures, which suggests a higher rate of dosage failure. Dingo activity was highest in both groups immediately after capture, but declined after the first hour in each. The activity of dingoes that accepted a drug TTD was significantly reduced compared to those that took the placebo. However, tooth and limb damage scores did not differ significantly between the drug and placebo group. Much of the physical trauma may have occurred within the first hour of capture when activity was intense and before drug onset in the TTD drug group. The use of TTDs containing sedative and anxiolytic drugs has the potential to reduce anxiety and distress associated with prolonged captivity, but the delivery of a lethal agent that is rapidly acting and humane may result in better welfare outcomes.

RESUMO: A origem da dispneia de esforço em doentes com DPOC é multifactorial. Alguns dos factores apontados são: o aumento da drive ventilatória1, a redução da capacidade dos músculos respiratórios 2 ou as anomalias do coupling neuromuscular da bomba ventilatória3, ambos associados a hiperinsuflação pulmonar dinâmica4.O treino ao exercício em doentes com DPOC tem demonstrado melhorar a capacidade para o exercício e a dispneia de esforço, sem contudo se verificarem alterações significativas da mecânica ventilatória, nomeadamente da capacidade inspiratória ou do volume pulmonar no final da inspiração, ou seja, a base mecânica para esta melhoria ainda não foi clarificada.O presente estudo pretende estudar os efeitos do treino ao exercício na drive ventilatória e no coupling neuromuscular ventilatório e a sua possível associação com a dispneia de esforço, com o pressuposto de que uma avaliação precisa destes efeitos é essencial no tratamento da dispneia em doentes com DPOC.Os autores avaliaram os efeitos de um programa de reabilitação de 6 semanas com treino ao exercício, em 20 doentes com DPOC moderada a grave. O programa incluiu a componente educativa, exercícios respiratórios e treino ao exercício. O treino ao exercício foi realizado em cicloergómetro, marcha e exercício dos membros superiores.Antes e após o programa de treino foi realizada a avaliação funcional respiratória em repouso e no exercício com teste incremental progressivo em cicloergómetro. Foi avaliado no esforço máximo, o consumo de oxigénio (VO2), a produção de dióxido de carbono (VCO2), a ventilação minuto (VE), as componentes de volume e de tempo do ciclo respiratório e, em seis doentes, foi avaliada a variação da pressão esofágica (Pessw) quer nos valores actuais quer como percentagem da pressão esofágica máxima medida numa manobra de sniff (Pessn), ao longo do exercício.Como resultados obtiveram um aumento significativo da capacidade para o exercício em resposta ao treino: aumento da carga máxima suportada (WR), do VO2, do VCO2, da VE, do volume corrente e da frequência cardíaca, enquanto a dispneia de esforço e a sensação de esforço dispendido pelos membros inferiores, avaliadas pela escala de Borg, não se modificaram significativamente. A relação da dispneia de esforço com o consumo de oxigénio e com a produção de dióxido de carbono (dispneia/VO2 e dispneia/VCO2) diminuiu, enquanto os equivalentes ventilatórios (VE/VO2 e VE/VCO2) não se alteraram. A dispneia de esforço e o esforço dos membros inferiores, quando relacionados com a ventilação minuto, diminuíram significativamente após o treino.Para uma carga padronizada, a ventilação minuto, o VCO2, a dispneia de esforço e o esforço dos membros inferiores diminuíram, enquanto a capacidade inspiratória (IC) aumentou.A redução da ventilação deveu-se em primeiro lugar à redução da frequência respiratória (RR) e ao aumento do tempo inspiratório (TI) e do tempo expiratório (TE). O volume corrente aumentou ligeiramente, enquanto a drive ventilatória (VT/ /TI) e o ciclo de trabalho ventilatório (TI /TTOT) se mantiveram inalterados.A redução da variação da pressão esofágica (Pessw) e o aumento do volume corrente (VT) associaram-se a uma menor dispneia de esforço após o programa de treino.Para valores padronizados de VE, VT, RR e IC, a variação de pressão esofágica â Pessw e Pessw(%Pessn)/VT â manteve-se inalterada, enquanto a dispneia de esforço e o esforço dos membros inferiores se reduziram com o treino ao exercício.Os autores concluem que os mecanismos fisiológicos envolvidos na redução da dispneia após o treino ao exercício são complexos, e os factores que parecem ter um papel mais importante são: os cardiovasculares, a redução das exigências ventilatórias, a redução da impedância à acção dos músculos ventilatórios e, ainda, factores não fisiológicos.Quanto aos factores cardiovasculares, os autores salientam o facto de o pulso de oxigénio (quantidade de oxigénio consumida por cada batimento cardíaco) ser, segundo um trabalho de Montes de Oca et al5, o melhor factor preditivo do consumo máximo de oxigénio em doentes com DPOC. Contudo, no presente trabalho, os autores não observaram um aumento do pulso de oxigénio com o treino, tornando o papel dos factores cardiovasculares menos relevante.No que diz respeito à redução das exigências ventilatórias, esta verifica-se neste trabalho, com a redução da ventilação-minuto e da produção de dióxido de carbono para uma mesma carga suportada. Estas alterações são consequência de um aumento da capacidade aeróbica com o treino, o que leva a uma menor produção de lactato e menor necessidade ventilatória para eliminar as valências ácidas.A redução da impedância à acção dos músculos ventilatórios deve-se a uma redução da insuflação pulmonar (menor volume pulmonar no final da expiração). A âdesinsuflaçãoâ que é proporcionada pela redução da frequência respiratória com prolongamento do tempo expiratório e com um maior volume de ar expirado permite, por sua vez, reduzir a carga elástica dos músculos respiratórios. Para a mesma carga suportada pelos doentes, o treino ao exercício reduz a dispneia ao diminuir o esforço inspiratório, o volume pulmonar no final da expiração e a frequência respiratória, melhorando assim o coupling neuro-ventilatório.Outros factores potencialmente implicados na redução da dispneia com o treino ao exercício são os factores não fisiológicos, de que é exemplo a dessenssibilização ou a tolerância à dispneia, permitindo aos doentes suportarem cargas mais elevadas e, possivelmente, o treino respiratório, permitindo uma melhoria do padrão ventilatório com redução da frequência respiratória. COMENTÃRIO: Os autores deste trabalho fazem uma análise dos efeitos fisiológicos e não fisiológicos do treino ao exercício. Alguns desses efeitos são o aumento da capacidade aeróbica (consumo máximo de oxigénio), da carga suportada, enquanto para uma mesma carga suportada a dispneia de esforço e a sensação de esforço dispendido pelos membros inferiores se reduziram significativamente após o programa de treino. Estes efeitos benéficos do exercício colocam-no como a chave de qualquer programa de reabilitação em doentes com DPOC. Segundo uma meta-análise realizada por Lacasse et al, os programas de reabilitação que incluem o treino ao exercício têm demonstrado uma melhoria da capacidade para o exercício, o alívio da dispneia e a melhoria da capacidade para lidar com a doença6.Um dos factores analisados pelos autores é a relação da melhoria do coupling neuro-ventilatório com a melhoria da dispneia obtida com o treino ao exercício. O conceito de coupling neuroventilatório tem sido enfatizado nos últimos anos. Ele reflecte a relação entre a força dos músculos inspiratórios (expressa pela razão entre a pressão esofágica inspiratória â Pessw â e a pressão inspiratória máxima â PImax) e a variação instantânea do volume pulmonar (razão entre o volume corrente â VT â e a capacidade pulmonar total â TLC):Pessw/PimaxVT/TLCA hiperinsuflação pulmonar, frequentemente presente nos doentes com DPOC, tem sido apontada como um factor que determina dissociação neuroventilatória. Se, por um lado, impõe aos músculos respiratórios uma maior carga elástica, obrigando a um maior esforço para que se possa manter um nível ventilatório adequado, por outro, a hiperinsuflação reduz a contractilidade máxima dos músculos que passam a operar numa relação comprimento/tensão mais desfavorável.Esta sensação de maior esforço, que não se traduz em variações proporcionais de débitos e volumes, constitui a dissociação neuromecânica ou neuroventilatória e tem como consequência a dispneia7.No trabalho que comentamos, para uma mesma carga suportada, o exercício reduziu a dispneia ao diminuir o esforço inspiratório, a hiperinsuflação pulmonar e a frequência respiratória, melhorando assim o coupling neuroventilatório.Outras formas terapêuticas, como a administração de broncodilatadores, também podem reduzir a dispneia de esforço nos doentes com DPOC, o que pode ser atribuído igualmente à redução da hiperinsuflação pulmonar e à melhoria do coupling neuroventilatório, já que nestes doentes não existe habitualmente um aumento importante dos débitos expiratórios8. Na maioria dos casos, o aumento do FEV1 com a broncodilatação não ultrapassa os 12%.Para além da coupling neuroventilatória, os autores pretenderam neste estudo avaliar os efeitos do treino ao exercício na drive ventilatória central. Durante muitos anos, o aparecimento da hipercapnia nos doentes com DPOC foi interpretado como consequência de uma redução do estímulo ventilatório que parte dos centros respiratórios (drive) para os músculos respiratórios. Sabe-se hoje que, quando comparados com indivíduos saudáveis, os doentes com DPOC apresentam antes uma drive ventilatória aumentada9. Esta pode ser avaliada pela pressão de oclusão (P0.1), pela variação da ventilação (VE) ou pelo débito inspiratório médio (VT/TI). O aumento da drive pode ser consequência do estímulo proveniente dos aferentes mecânicos pulmonares ou da parede torácica e dos quimiorreceptores estimulados pela hipóxia crónica10.Embora outros autores1 apontem a drive como um dos factores que pode estar na génese da dispneia, neste trabalho os autores verificaram que a drive ventilatória, avaliada pelo VT/TI, não se alterou significativamente com o treino ao exercício, não parecendo ter influência na melhoria da dispneia de esforço referida por estes doentes.Salienta-se a importância de estudos como este, por proporcionarem uma melhor compreensão dos mecanismos de acção de algumas modalidades terapêuticas como o treino ao exercício na melhoria da dispneia de esforço em doentes com DPOC. Palavras-chave: treino ao exercício, DPOC, dispneia, coupling neuroventilatório, drive ventilatória, Key-words: exercise training, COPD, dyspnea, neuromuscular coupling, ventilatory drive

Conjunctivitis, or inflammation of the conjunctiva, usually occurs as a result of infection or allergy. It is an exceedingly common occurrence, certainly the most common acute disease of the eye seen by primary care physicians of children. When it occurs in the neonatal period, it has been given the appellation ophthalmia neonatorum; in older infants and children, it sometimes is called "pink eye." This review covers the etiology, epidemiology, pathogenesis, diagnosis, and therapy of conjunctivitis in infants and children. Etiology Neonatal conjunctivitis occurs in 1.6% to 12% of newborns during the first month of life. The chemical irritation from antimicrobial prophylaxis against bacterial infection is the most frequent cause, followed by Chlamydia trachomatis infection. Other important pathogens in this setting are Haemophilus influenzae and Streptococcus pneumoniae. It is unusual to isolate any of these organisms from healthy eyes. Various streptococci and Staphylococcus aureus have been isolated not only from significant numbers of infected eyes, but also from a substantial number of healthy eyes, leaving their exact role less clear. Rarely, gram-negative organisms such as Escherichia coli, Klebsiella, or Pseudomonas sp have been implicated as causes of neonatal conjunctivitis, especially in infants in intensive care units. Neisseria gonorrhoeae no longer is a major cause of neonatal conjunctivitis in this country because of the mandated use of neonatal ocular prophylaxis.

One of the most common applications of snore sound analysis is to find out its relationship with obstructive sleep apnoea (OSA). The present work is aimed at developing a method for processing full night snore recordings obtained from a simple recording system that can be used both for clinical and home application. Automatic extraction of snore sounds only could in fact allow for saving much time usually required for manual analysis

Background Portal vein thrombosis is a frequent complication in liver cirrhosis. Encouraging reports of systemic thrombolysis in non-cirrhotic patients suffering from acute portal vein thrombosis led us to start a pilot study on the efficacy and safety of systemic low dose recombinant tissue plasminogen activator (Actilyse®, Boheringer Ingelheim, Florence, Italy). Patients Nine cirrhotic patients (6 males and 3 females) with recent portal vein thrombosis were enrolled. Exclusion criteria were portal cavernomatosis, recent (30 days) surgery, active bleeding, hepatocellular carcinoma and cancer in other sites. Methods All cases were treated for a maximum of 7 days by continuous i.v. infusion of 0.25 mg/kg/die of r-tPA plus subcutaneous low molecular weight heparin. Efficacy was evaluated by colour doppler sonography monitoring and confirmed by contrast enhanced computerized tomography. Results The combined r-tPA/LMWH treatment was well tolerated without clinically significant side effects. Complete resolution of thrombosis occurred in 4 cases, partial regression in 4 and none in 1. Retreatment of a complete recurrence in 1 patient was successful. Variceal pressure dropped from 30.7 ± 4.5 mmHg to 21.2 ± 6.6 mmHg (p = 0.012). Conclusions Our preliminary data demonstrate that thrombolytic treatment of recent portal vein thrombosis with i.v. r-tPA and LMWH in patients with cirrhosis appears to be safe and effective and can significantly reduce pressure in oesophageal varices.

D-dimer and factor VIII levels raise in advanced cirrhosis. We investigated the behavior and the diagnostic usefulness of D-dimer and factor VIII in cirrhotic patients with asymptomatic portal venous thrombosis. Factor VIII coagulant and D-dimer values were measured in 136 consecutive outpatients with stable cirrhosis divided according to Child-Pugh (CP) classification, who underwent color/power ultrasonography to detect portal thrombosis. Portal thrombosis was found in 33 patients (24.2%). In patients without thrombosis, factor VIII was significantly higher in CP class C compared with class A and B. Conversely, class C patients with portal thrombosis had lower factor VIII levels than those without thrombosis. In both groups, D-dimer was significantly increased in class C compared with class A and B. In class C, thrombotic patients showed higher D-dimer values than did patients without thrombosis. In class C, a D-dimer valueor = 0.55 microg/mL provided a sensitivity and a negative predictive value for portal thrombosis of 100%, and a factor VIII coagulant levelor = 80% showed a specificity and a negative predictive value of 76% and 84%, respectively. In class B, a D-dimer valueor = 0.225 microg/mL had a sensitivity of 89% and a negative predictive value of 82%. In conclusion, our study shows that factor VIII values increase in severe cirrhosis but significantly decrease in the presence of concomitant portal thrombosis, likely because of consumption during thrombosis; D-dimer is enhanced by both liver failure and portal thrombosis; in severe cirrhosis, normal D-dimer and factor VIII values may safely exclude the presence of asymptomatic portal thrombosis.

Dyspnea is a global expression that encompasses all uncomfortable stimuli and their associated sensation or expression [1]. In exercising patients with chronic airway obstruction (CAO) and controls, respiratory effort, unrewarded inspiration, and inspiratory difficulty are most frequently reported as dyspnea symptoms [2]. In patients with asthma, during bronchoconstriction the symptoms may vary from chest tightness to inspiratory effort [3].

Static mouth pressure during maximal inspiratory efforts is commonly used to evaluate inspiratory muscle strength. However, maximal inspiratory pressure (MIP) presents some potential limitations likely to be overcome by the measure of mouth pressure during a maximal sniff maneuver in patients with respiratory muscle weakness. The aim of the present study was to assess whether mouth pressure during sniff maneuver (Pmosn) is a better index of inspiratory muscle strength than MIP in patients with neurologic and neuromuscular diseases (NNMD) with and without inspiratory muscle weakness.Both MIP and Pmosn were measured in 30 patients affected by various types of NNMD and in 41 control subjects. Pmosn was measured with a 5-cm latex balloon-catheter system, the balloon being held in the oral cavity with the lips closed.In control subjects, MIP was either similar (in female subjects) or higher (in male subjects) than Pmosn, the variation coefficients for the two tests being similar both in male subjects (19.3% vs 19.1% for MIP and Pmosn, respectively) and in female subjects (27.5% vs 26.2%, respectively). There was no difference in the Pmosn/MIP ratios observed in the different diseases (one-way analysis of variance, F = 0.29, p = 0.91). In control subjects, a significant inverse relationship between Pmosn/MIP ratio and MIP (r = - 0.66, p0.00001) was found, ie, the lower the MIP, the higher the Pmosn/MIP ratio, suggesting an increasing difficulty in performing MIP as MIP values decreased. The majority of patients were between the prediction limits of the regression calculated for control subjects. At variance, patients with Duchenne dystrophy and low MIP were under the prediction limits of the regression calculated for control subjects, indicating a lower-than-expected PMOSN.In patients with NNMD, irrespective of the etiology, we found the following: (1) Pmosn does not overcome the limitations of MIP measurement; (2) the two maneuvers are not interchangeable, but rather complement one another in the assessment of inspiratory muscle strength; (3) Pmosn may underestimate muscle strength as assessed by MIP in patients with NNMD with inspiratory muscle weakness; and (4) in patients with low MIP, the lower-than-expected Pmosn/MIP ratio confirms inspiratory muscle weakness.

Infants born to human immunodeficiency virus type 1 (HIV-1)-infected mothers were immunized at birth and at ages 4, 12, and 20 weeks with low-, medium-, or high-dose recombinant gp120 vaccine with MF59 adjuvant (HIV-1 SF-2 ; n = 52) or with MF59 alone as a placebo (n = 9). An accelerated schedule (birth and ages 2, 8, and 20 weeks) was used for an additional 10 infants receiving the defined optimal dose and for 3 infants receiving placebo. At 24 weeks, anti-gp120 ELISA titers were greater for vaccine-immunized than for placebo-immunized infants on both schedules, and 87% of vaccinees had a vaccine-induced antibody response. At 12 weeks, antibody titers of infants on the accelerated vaccine schedule exceeded those of infants receiving placebo (4949 vs. 551; P = .01), and 63% of the vaccinees met the response criteria. Thus, an accelerated schedule of gp120 vaccinations generated an antibody response to HIV-1 envelope distinct from transplacental maternal antibody by age 12 weeks. These results provide support for further studies of vaccine strategies to prevent mother-to-infant HIV-1 transmission.

Chronic expiratory flow limitation and hyperinflation are the mechanical hallmarks of chronic obstructive pulmonary disease (COPD). Although carbon dioxide retention is dependent on the severity of airflow limitation, there is considerable variability in the relationships between arterial carbon dioxide tension (Pa,CO2) and forced expiratory volume in one second (FEV1) or total lung resistance (RL). In stable COPD patients with severe airflow obstruction, shallow breathing and inspiratory muscle weakness are the main factors associated with CO2 retention. In stable COPD patients, the diaphragm is less effective than in normal subjects and, with increasing airflow obstruction and hyperinflation, the contribution to the generation of ventilatory pressure of the ribcage inspiratory muscles increased. Abdominal muscles are recruited during expiration in severe COPD patients and the expiratory rise in gastric pressure is directly related to intrinsic positive end-expiratory (alveolar) pressure (PEEPi). During acute bronchoconstriction, COPD patients with severe airflow obstruction recruited the rib cage inspiratory muscles proportionally more than the diaphragm. The associated recruitment of abdominal muscles results in a reduction in abdominal volume at end-expiration and contributes to a significant extent to PEEPi. Dynamic hyperinflation can be overestimated during chronic and acute airway obstruction if abdominal muscle function is not evaluated.

A clear understanding of the pathogenesis of fungal disease remains elusive. While technological advances in molecular biology and microbial genetics have provided scientists with major new insights into both microbial virulence factors as well as host susceptibility to infection, there is currently no substitute for animal models in elucidating microbe-host interactions. Animal models are also essential for the evaluation of new antimicrobial agents, including studies of efficacy, adverse reactions and pharmacokinetics. The single most important advance in animal models in the last decade, has been the availability of genetically unique strains of animals as alternative to animals treated with immunosuppressive drugs for use in studies on microbial virulence and host defence mechanisms. These unique strains of test animals also enhance our understanding of the modes of action of antifungal drugs and their metabolism. Some of these advances will be discussed in this symposium.

Studies of Pneumocystis carinii have been limited by our inability to propagate it in continuous culture. In this context, studies of P. carinii antigens have provided significant insight into the biology of this organism. The mannose-rich surface major surface glycoprotein of P. carinii termed glycoprotein A (gpA) is the best studied of these P. carinii antigens. Significant genetic and immunologic diversity exists between the gpA molecules expressed by P. carinii derived from different mammalian sources. The molecular and biochemical nature of gpA and other P. carinii antigens including p55 are reviewed. In addition, available information concerning the role of P. carinii gpA and other antigens in host-organism interactions are also discussed.

Jet engine and gas turbine hot section components can be protected from the 1,350--1,650 C combustion gases by thermal barrier coatings (TBCs). Metallic candidates for functionally graded material (FGM) coatings have been evaluated for potential use in bonding zirconia to a single crystal superalloy. Properties for four materials were studied for the low-expansion layer adjacent to the ceramic. Ingots were produced for these materials, and oxidation, expansion and modulus were determined. A finite element model was used to study effects of varying the FGM layers. Elastic modulus dominated stress generation, and a 20--25% reduction in thermal stress generated within the zirconia layer may be possible.

Whether or not short-term negative pressure ventilation (NPV) improves respiratory function by decreasing the drive to the respiratory muscles in hypercapnic chronic obstructive pulmonary disease (COPD) patients remains to be defined. In six severely obstructed hypercapnic COPD patients (Group A) with grade IV dyspnoea (modified Medical Research Council (MRC) dyspnoea scale), we evaluated pulmonary volumes, arterial blood gases, the pattern of breathing (tidal volume (VT) and respiratory frequency (Rf)) and the neuromuscular respiratory drive (NMRD), before and immediately after a 7 day period with the iron lung (IL). NMRD was assessed by expressing mouth occlusion pressure (P0.1) recorded during quiet breathing as a percentage of maximal P0.1 recorded during exogenous CO2 stimulation (P0.1 max,CO2). A group of six hypercapnic, less dyspnoeic (grade II to III) COPD patients (Group B), with similar mechanical characteristics, and another less obstructed historically normocapnic control group (Group C) were also considered. Before IL, in Group A VT was lower than in C, and P0.1 (%P0.1 max,CO2) was greater than in Group B and C. After a 7 day period with IL, VT increased, Rf decreased, and arterial blood gases and dyspnoea grade improved; P0.1 (%P0.1 max,CO2) significantly decreased remaining, however, greater than in Group C. In Group A the time course of arterial carbon dioxide tension (Pa,CO2) and P0.1 (%P0.1 max,CO2) were significantly related to each other. These data seem to indicate that IL is effective in improving respiratory function and symptoms in chronic hypercapnic severely dyspnoeic COPD patients. The observation that these effects were associated with a decrease in NMRD reflects an improved efficiency of the respiratory system. After IL, respiratory function in Group A was similar or even better than that in Group B. This study also considers the possibility of putting severely dyspnoeic hypercapnic COPD patients into an IL trial before starting a traditional rehabilitation programme.

Broxaterol, a new selective beta 2-agonist, has been shown to exert inotropic effects on both fresh and fatigued canine diaphragm. We evaluated the effect of broxaterol on the activation and force output of the respiratory muscles in patients with chronic obstructive pulmonary disease (COPD). We studied 9 patients with moderate to severe COPD. Each patient was infused with saline and Broxaterol (200 micrograms) in saline alternately. We measured lung volumes, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), breathing pattern, P0.1, respiratory muscle EMG (diaphragm, EMGd, and parasternal, EMGp) and P0.1/EMGd ratio. Measurements were made under control conditions and at 15, 30, 60, and 120 min after each infusion. Broxaterol, but not saline, resulted in a slight but significant increase in vital capacity (VC), forced expiratory volume in one second (FEV1) and MIP, and a decrease in functional residual capacity (FRC). Breathing pattern did not change, while EMG significantly decreased, and P0.1/EMGd significantly increased in 5 of the 9 patients after broxaterol. These data seem to indicate that by partially unloading the respiratory muscles, broxaterol results in decreased muscle activation (EMG). Increase in chest wall neuromuscular coupling (P0.1/EMGd) may also be observed.

The mannosylated surface glycoprotein (gp) of Pneumocystis carinii has one known conserved epitope that is recognized by the monoclonal antibody 85-1-5E12. The gp exhibits host species-specific antigenic variation, exhibits host species-specific collagenase sensitivity, and varies in size depending on the host of origin and the method of preparation. These data support the existence of host species-specific serotypes of P. carinii.

Pneumocystis carinii gp120 can elicit a specific T-cell proliferative response in mice after immunization with a gp120 preparation or with a crude P. carinii homogenate. It can also elicit a proliferative response from SCID mice after recovery from natural infection with P. carinii, implicating this glycoprotein as an important antigen in the host's response to P. carinii infection.

The use of poison baiting in Australia to control foxes is impractical in urban areas and some wildlife reserves because of hazards to non-target animals. More acceptable methods of fox control in such environments are needed. Cabergoline is a dopamine agonist that has previously been demonstrated to have an abortifacient effect in cats (Felis catus) and dogs (Canis familiaris). The prolactin-inhibiting action of cabergoline may also result in cessation of lactation. Cabergoline has been shown to be completely palatable to foxes and is easily incorporated into a non-poisonous bait. The ability of bait-delivered cabergoline to effect the birth of viable fox cubs was tested in urban Melbourne and rural Bendigo, Victoria. A sample of 51 natal dens were chosen for this study on the basis that they had been active for 3 consecutive years (1991-93). 30 treatment dens were randomly selected and each treated once during August and again during September 1994 with 8 non-poisonous Foxoff baits containing 170 micro g of cabergoline and 200 mg of tetracycline to act as a biomarker. The remaining 21 dens were used as controls. Baits were randomly placed by burial within a 50-m radius of the den. Activity of all dens was assessed until December 1994 for direct/indirect signs of fox cubs. Bait uptake was >88% overall for the treatment dens. The resulting incidence of cubs was significantly lower in the treatment dens than in the controls. The potential for cabergoline to be used in urban areas and island populations as an adjunct to conventional control methods is discussed.

Both vagal and non-vagal afferences from the lung or chest wall contribute to increasing neural drive to the respiratory muscles, but only the former are known to change the breathing pattern by increasing respiratory frequency (RF) during bronchoconstriction. In order to evaluate the relative contribution of vagal and non-vagal afferences to increasing neural drive to the respiratory muscles in 14 asymptomatic asthmatic patients known to be responsive (decrease in FEV1 greater than 20% of the control values) to previous bronchial provocation test (BPT) with aerosolized histamine, we evaluated FEV1, breathing pattern and neuromuscular drive, as assessed by mouth occlusion pressure (PO.1), under control conditions, during BPT with progressive doubling doses of inhaled histamine (H) and 5 min after inhalation of a bronchodilator agent (Reproterol) (B). During HBPT FEV1 exhibited a significant decrease (p less than 0.01) while PO.1 was found to increase significantly (p less than 0.01). However, no significant changes were noted in breathing pattern. After B FEV1 returned to control values while PO.1, even if significantly reduced (p less than 0.01), did not. Changes in PO.1 were found to be significantly related to changes in FEV1 both during HBPT and B (p less than 0.05). The data suggest that in these patients non-vagal afferences, linked to the abnormalities of thoraco-pulmonary mechanics, could play a major role in changing neural drive to the respiratory muscles.

Publisher Summary The ability to manipulate the immune response is becoming more of a reality as understanding of the immune system improves. Immunotherapy is defined as the use of either naturally occurring substances or drugs to modify the immune response to a particular antigen. It offers a possible modality to improve the ability to prevent or treat infectious diseases. The past decade has seen a renewed interest in manipulating the immune response to both prevent and treat infections. The manipulation of the immune system by drugs, natural or synthetic products, or derivatives of these products represents an attractive adjunct in the treatment of infections. Many of the experimental foundations for this approach have been laid by the expanding knowledge of endogenous regulators and mediators of lympho-myeloid cooperation and differentiation. Human interferon and specific monoclonal antibodies have been produced in vitro and both have been used or are likely to be used in clinical trials against numerous viruses and pathogenic organisms. The role of these modulatory agents may be three-fold: enhancement of phagocytosis of infectious agents, restoration of impaired immune functions, and treatment of infections without exerting selective pressure on microbial populations that is an inherent problem with antibiotic therapy. This review serves to update the reader on the rationale for immunotherapy and some of the more recent and significant advances in the immunotherapy of infectious disease.

A program to assess the feasibility of Directionally Solidified Eutectic (DSE) High Pressure Turbine (HPT) blades is described. The overall objectives of the program were to define the materials, design and fabrication technology required for the application of eutectic composites in HPT blade components and, through engine testing, to demonstrate their applicability in advance aircraft gas turbine engines. NiTaC-14B a DSE alloy, has a combination of mechanical properties judged to be superior for turbine blade applications over all other known eutectics. It has a potential temperature advantage of 225OF over the conventionally cast superalloy Rene' 80 and lOOoF over the directionally solidified (DS) alloy Rene' 150. A NiTaC-14B blade for testing in a demonstrator engine was designed by significantly modifying the existing DS Rene' 150 blade. The cooling air was markedly reduced and the pitchline airfoil temperature predicted to increase by lOOoF. This allowed an effective evaluation of NiTaC HPT blade capabilities under realistic engine conditions. Hollow HPT blades for test evaluations were cast as close to final external dimensions as practical. Complex internal air cooling passages were cast to size through the use of a new alumina core material/processes developei by General Electric under Air Force sponsorship. A shell mold developed by General Electric was used to form the external blade surfaces. However, because of surface defects in castings made with this mold, the blade was cast oversize to provide sufficient stock for removal of such defects. HPT blades were finish machined and then subjected to a series of bench tests. The results were combined with blade life analysis results to assess the adequacy of the blade design for engine testing. Subsequently, eight uncoated blades were successfully engine tested. The program demonstrated that the mechanical properties of the selected NiTaC alloy are very good and that although processing is difficult the manufacture of engine quality hollow DS eutectic blades is feasible.

Pneumocystis carinii pneumonia (PCP) was provoked in the ferret, Mustela pulorius furo, by immunosuppression with daily long-term administration of cortisone acetate, 10-20 mg/kg subcutaneously for 9 to 10 weeks, Microscopically P. carinii was observed in the lungs of all 11 treated animals: mild to moderate in five and extensive disease in six. The histopathological features of PCP in the ferret included interstitial pneumonitis, scant mononuclear cell alveolitis, with abundant cysts and trophozoites visible in a focal distribution. There were few neutrophils present. Electron microscopy showed large numbers of both cysts and trophozoites in close association with type I cells. No bacterial pathogens were isolated from the lungs of immunosuppressed animals but an unexplained eosinophilic enteritis was present in treated animals. P carinii pneumonia developed without significant body weight loss during corticosteroid administration, unlike previously described studies using corticosteroid-treated rodents. Ferrets thus appear to be a 'steroid resistant' animal, like man, and therefore a more suitable model for immunological studies of host response to PCP than rodents. This new model also has practical advantages over previously described animal models of PCP, including larger lung and airway size.