Chemical Ecology of the host searching behavior in an Egg Parasitoid: are Common Chemical Cues exploited to locate hosts in Taxonomically Distant Plant Species?

Parasitoids are known to exploit volatile cues emitted by plants after herbivore attack to locate their hosts. Feeding and oviposition of a polyphagous herbivore can induce the emission of odor blends that differ among distant plant species, and parasitoids have evolved an incredible ability to discriminate them and locate their hosts relying on olfactive cues. We evaluated the host searching behavior of the egg parasitoid Cosmocomoidea annulicornis (Ogloblin) (Hymenoptera: Mymaridae) in response to odors emitted by two taxonomically distant host plants, citrus and Johnson grass, after infestation by the sharpshooter Tapajosa rubromarginata (Signoret) (Hemiptera: Cicadellidae), vector of Citrus Variegated Chlorosis. Olfactory response of female parasitoids toward plants with no herbivore damage and plants with feeding damage, oviposition damage, and parasitized eggs was tested in a Y-tube olfactometer. In addition, volatiles released by the two host plant species constitutively and under herbivore attack were characterized. Females of C. annulicornis were able to detect and significantly preferred plants with host eggs, irrespectively of plant species. However, wasps were unable to discriminate between plants with healthy eggs and those with eggs previously parasitized by conspecifics. Analysis of plant volatiles induced after sharpshooter attack showed only two common volatiles between the two plant species, indole and ß-caryophyllene. Our results suggest that this parasitoid wasp uses common chemical cues released by many different plants after herbivory at long range and, once on the plant, other more specific chemical cues could trigger the final decision to oviposit.

Volatiles mediate host-selection in the corn hoppers Dalbulus maidis (Hemiptera: Cicadellidae) and Peregrinus maidis (Hemiptera: Delphacidae).

Volatile organic compounds (VOCs) released by plants are generally involved in host recognition and host selection for many phytophagous insects. However, for leafhoppers and planthoppers, host recognition is mainly thought to involve a phototactic response, but it is not clear if a host plant could be selected based on the volatile cues it emits. In this study we evaluated olfactory responses in dual choice tests of two Hemiptera species, Dalbulus maidis (De Long) (Cicadellidae) and Peregrinus maidis (Ashmead) (Delphacidae), vectors of maize-stunting diseases, to three maize (Zea mays L.) germplasms, a temperate and a tropical hybrid and a landrace. VOCs emitted by the germplasms were collected and identified using gas chromatography-mass spectrometry. The temperate hybrid released significantly more VOCs than the tropical hybrid and the landrace, and its volatile profile was dominated by (±)-linalool. D. maidis preferred odours emitted from the temperate hybrid, whereas P. maidis preferred odours from the tropical hybrid and the landrace over the temperate one. In order to test if linalool plays a role in the behavioural responses, we assayed this compound in combination with the tropical hybrid, to provide other contextual olfactory cues. D. maidis was attracted to the tropical hybrid plus a 0.0001% linalool solution, indicating that this compound could be part of a blend of attractants. Whereas addition of linalool resulted in a slight, though not significant, reduction in host VOC attractiveness for P. maidis. Both hopper species responded to olfactory cues in the absence of supplementary visual cues.

Fluoroscopy-guided placement of nasoenteral tubes in children using intermittent digital pulse fluoroscopy and last image save/grab technique.

AIM: To document the radiation exposure metrics, including fluoroscopic radiation time and radiation dose-area product, in children <18 years of age who undergo nasoenteral tube placement using fluoroscopic guidance with maximal dose-reduction techniques. MATERIALS AND METHODS: Following institutional review board approval, the age, gender, anatomical information, immediate procedure-related complications if any, fluoroscopy time, and radiation dose-area product were collected retrospectively in all paediatric patients who underwent fluoroscopically guided nasoenteral tube placement during a 5-year period. Three paediatric radiology faculty members, a radiologist assistant, and trainee residents during their paediatric radiology rotation performed the procedures on two different digital fluoroscopic machines using radiation-minimising techniques. Median values of the fluoroscopy time and radiation dose-area product were calculated and compared to values reported in the literature using the Wilcoxon procedure. RESULTS: There were 41 male and 33 female patients with a median age of 4 years and 6 months. Median fluoroscopy time used for placing a nasoenteral tube was 1.25 minutes with a median radiation exposure dose-area product of 0.245 Gy·cm(2). All patients had successful placement of nasoenteral tube without immediate procedure-related complications. CONCLUSION: Fluoroscopy-guided nasoenteral feeding tube placement can be performed successfully with minimal radiation exposure without compromising procedural success.

Age dependence of serum enzymatic activities (alkaline phosphatase, aspartate aminotransferase, and creatine kinase) in healthy children and adolescents.

The activities of alkaline phosphatase, aspartate aminotransferase and creatine kinase in sera of 1,033 children and adolescents aged 5 to 20 years were measured. The results showed significant deviation from the gaussian distribution. Because of differences between sexes and nonlinear relationship to age, sex- and age-related values for the 95th, 90th, and 5th percentiles are presented. Alkaline phosphatase activity increased markedly between 5 and 14 years of age in male subjects and 5 and 12 years of age in female subjects. The peak at puberty was more pronounced in boys than in girls. After puberty, activities decreased toward adult values. Aspartate aminotransferase activity showed a gradual significant decrease between 5 and 17 years of age in male subjects and 5 and 16 years of age in female subjects; then it remained steady until 20 years of age. Creatine kinase activity remained constant in male subjects between 5 and 12 years old, then rose to a maximum at 15 to 16 years of age before declining rapidly toward adult values. In female subjects, creatine kinase activity remained stable from 5 to 12 years of age, then decreased gradually in early adulthood.

Percentile estimates of reference values for fourteen chemical constituents in sera of children and adolescents.

The concentrations of 14 chemical constituents in sera of 1,062 children and adolescents aged 4 to 20 years were measured and their 5th and 95th percentiles were calculated. The distribution of values for all constituents showed significant deviation from the gaussian when the results were combined, regardless of age and sex, except for magnesium. Although certain chemical constituents showed statistically significant relationships with age and sex, two additional criteria based upon the coefficient of variation of the method employed were utilized to judge the effectiveness of computing stratified reference values. After applying these corrections the reference values established were classified into three categories, viz. (1) those where the relationship to age and sex remained significant (inorganic phosphorus and creatinine); (2) those where the relationship to age only remained significant (total protein); (3) those where no significant relationship to age and sex was obtained (all other constituents).

Caring for our future: a report by the expert panel on the content of prenatal care.

The report of the Expert Panel on Prenatal Care entitled Caring for Our Future: The Content of Prenatal Care was presented to the Assistant Secretary for Health, James Mason, MD, on October 2, 1989. The Panel noted the need for attention not only to the mother and fetus, but also to the infant and family. Besides traditional medical care concerns, the importance of psychosocial and environmental patient and family needs was emphasized. The Panel felt that the addition of the pre-conception visit to routine prenatal care made care more effective. Suggestions as to visit timing and content were made. The Panel noted the need for further understanding of many of the activities performed routinely in prenatal care.

Blunt cardiac rupture. The Emanuel Trauma Center experience.

OBJECTIVE: To analyze the factors affecting outcome in patients with blunt cardiac rupture, including anatomical cardiac injury, associated injury, clinical presentation, age, mechanism of injury, diagnostic method, surgical intervention, and presence of vital signs in the field and on arrival. DESIGN: Retrospective review. SETTING: A community-based level I trauma center. PATIENTS: A consecutive series of 27 patients seen between 1984 and 1993. MAIN OUTCOME MEASURE: Survival with return to preinjury activity. RESULTS: Eleven patients (41%) survived resuscitation, surgery, and initial hospital care. Survivors had a lower mean Injury Severity Score (38) than nonsurvivors (62) (P < .05). Three (33%) of nine patients who arrived with no blood pressure or viable electrical heart rhythm survived. No patient survived rupture of two cardiac chambers. CONCLUSIONS: Patients with blunt cardiac rupture who present with cardiac arrest can survive. Nonsurvivors tend to have more associated injuries, as indicated by higher Injury Severity Scores. Our institution's overall survival rate of 41% (11/27) compares favorably with rates at other trauma centers.

Emergent applications of cardiopulmonary support: a multiinstitutional experience.

The use of emergent portable bypass systems is increasing. Because of limited patient use in any one institution, a combined experience can better determine the applicability of these systems. A total of 187 patients from 17 centers were analyzed. Causes leading to bypass initiation were cardiac arrest (125 patients), cardiogenic shock (44), profound hypothermia (7), pulmonary insufficiency (9), and miscellaneous (2). Weaning from bypass was successful in 30.5% (57 patients). Sixty-four patients (34.2%) were transferred to standard bypass or other modes of circulatory assist. Of the total population, 40 patients (21.4%) were alive greater than 30 days. There were no survivors of unwitnessed arrests. Major diagnostic or therapeutic interventions were carried out on bypass in 74.9% of all patients. In survivors, 77.1% (37/48) had major therapeutic interventions as compared with 50.0% (67/135) of nonsurvivors. Emergency portable bypass systems can successfully resuscitate and support cardiac hemodynamics, although the underlying causes necessitating bypass remain difficult to correct. When corrective intervention can be performed, there is an increased chance of survival. Unwitnessed arrest, prolonged cardiopulmonary resuscitation, and lack of treatment options are relative contraindications. Appropriate patient selection and early application of these systems should lead to improved survival.

Emergency coronary artery bypass graft surgery in abciximab-treated patients.

BACKGROUND: Although the platelet antiaggregant abciximab is frequently used with percutaneous coronary interventions, results of emergency coronary artery bypass graft operations in patients recently treated with abciximab are poorly characterized. METHODS: During a 29-month period, 12 patients required emergency coronary artery bypass grafting within 12 hours (mean, 1.9 hours) of abciximab therapy. Our full standard heparin dose regimen was used (mean heparin dose, 53,000 U per patient). Each patient received a single platelet transfusion dose after protamine administration, and further blood products were transfused as necessary. Clinical outcome and transfusion requirements were compared with predicted results based on risk-adjusted historical patients. RESULTS: No patients died and none were returned to the operating room for coagulopathy-related bleeding. Per patient transfusion requirements were as follows: red blood cells, 3.6 units; apheresis platelets, 1.4 units; and fresh frozen plasma, 1.5 units. As compared with predicted values, there was no excessive incidence of mortality, stroke, or red blood cell transfusion requirements. CONCLUSIONS: Emergency coronary artery bypass graft operations using full-dose heparin can be performed successfully in acutely ischemic abciximab-treated patients. Prophylactic transfusion of platelets after protamine administration appears to be useful.

Interhospital transport of the patient on extracorporeal cardiopulmonary support.

Portable extracorporeal cardiopulmonary support systems have enhanced the resuscitation and support of moribund patients outside of the operating room environment. The literature documents the successful application of emergency cardiopulmonary support within the hospital setting. Clinicians have reported the use of helicopter and ground ambulance to transport patients requiring intraaortic balloon counterpulsation and fixed-wing transport of neonates requiring extracorporeal membrane oxygenation. As medical transport capabilities extend the sphere of tertiary care to outlying medical facilities, there is a role for extracorporeal cardiopulmonary support in the initial stabilization and safe transport of critically ill patients, via air or ground ambulance. Potentially, the early application of life-sustaining technology can lower mortality and morbidity in patients with a survivable pathology. This is a report on the experience with the resuscitation and interhospital transport of patients on extracorporeal cardiopulmonary support.

A rapid micromethod for measuring theophylline in serum by reverse-phase high-performance liquid chromatography.

We describe an assay system for measuring theophylline in 25 microliters of serum. The procedure involves extraction with a 95:5 mixture of chloroform:isopropanol containing beta-hydroxypropyltheophylline as internal standard, and reverse-phase chromatography on a 4 mm x 30 cm column containing "micron Bondapak C18." Theophylline and beta-hydroxypropyltheophylline are eluted with a 90:10 mixture of sodium acetate butter (20 mmoles/litre pH 4.0) and acetonitrile at a flow rate of 1.8 ml/min., are detected by their absorbance at 254 nm, and quantitated by measuring peak areas. Column temperature has not been found to be critical in this analysis. Each analysis requires 9 minutes of chromatography time with a total analysis time of 20 minutes. Analytical recoveries were found to be 71 to 75% for theophylline and 94% for beta-hydroxypropyltheophylline. This difference in recovery is corrected when determining the theophylline concentration in unknown samples. The method has good precision (coefficients of variation between 7.0% and 7.9% for therapeutic and toxic concentrations). The results obtained with this method compare favourably with results obtained by a published cation-exchange high-performance liquid chromatographic method. None of the metabolites of theophylline, common compounds related to theophylline in structure or drugs tested have been found to interfere with the analysis described.

Performance characteristics of the Coulter Kem-O-Lab.

We evaluated the performance characteristics of the Coulter Kem-O-Lab for the measurements of calcium, inorganic phosphate, total protein, albumin, glucose and urea nitrogen in serum. The precision on replicates agreed with those claimed by the manufacturer. All methods showed acceptable total precision measured over a four-week period, except for urea nitrogen. There was significant correlation between the Kem-O-Lab and routine methods, but the slope was significantly different from unity for calcium, total protein and urea nitrogen indicating a bias in their determinations. While turbidity and hemoglobin significantly interfered with measurements in all methods, bilirubin interference was observed only for total protein and glucose. There were no interferences due to any of the nine drugs tested.

A rapid, sensitive method for accurate analysis of individual bile acids in biological fluids by high performance thin-layer chromatography and densitometry.

1. A rapid new micromethod for quantitative analysis of individual bile acids in duodenal juice by high performance thin-layer chromatography (HPTLC) and densitometry is described and evaluated by comparison with standard TLC and spectrophotometry. 2. Advantages of HPTLC over TLC include more rapid separation, better resolution and more sensitive detection (5 - 10 fold), without the need for prior extraction. Densitometry provides simple, direct and rapid quantitation. 3. The method is accurate and reliable over a range of bile acid concentrations. In the 0.5 mM range, recovery was greater than 89%, and coefficients of variation for within-day analysis were 2 - 12% and for between-day analysis were 6 - 18% for the individual bile acids. Twenty analyses can be performed by one worker in a single day. 4. We conclude that the method offers several advantages over most currently described techniques, is suitable for routine use and is deserving of wider application.

Extracorporeal cardiopulmonary life support with heparin-bonded circuitry in the resuscitation of massively injured trauma patients.

BACKGROUND: Patients who have massive but potentially survivable injuries frequently die from complications of hypovolemia, hypoxemia, hypothermia, metabolic acidosis, and coagulopathy. Emergency cardiopulmonary bypass has been unsuccessful in preventing such deaths because it involves systemic anticoagulation that exacerbates coagulopathy. PATIENTS AND METHODS: A simplified extracorporeal cardiopulmonary life support (ECLS) system was assembled consisting of a centrifugal pump head, heat exchanger, membranous oxygenator, percutaneous cannulas, and heparin-bonded circuitry. The entire system has heparin-bonded surfaces. Patients were resuscitated with the system after femoral vein-femoral artery cannulation. ECLS was used to resuscitate massively injured patients who were deteriorating despite maximal conventional therapy. RESULTS: While receiving maximal conventional therapy, 6 patients developed hypothermia, metabolic acidosis, and coagulopathy causing pulmonary hemorrhaging and hypoxemia from severe underlying lung injuries. ECLS with heparin-bonded circuitry provided cardiopulmonary support and rewarming while physicians addressed coagulopathies and surgical bleeding and assessed survivability. Three patients survived. CONCLUSIONS: ECLS with heparin-bonded circuitry offers supplemental capability in the resuscitation and cardiopulmonary support of selected massively injured patients while their primary injuries are being evaluated and treated.

Chemosensitivity testing predicts survival in ovarian cancer.

The aim of this study was to assess the use of the MTT assay for chemosensitity testing to identify drug resistance and predict survival in patients with advanced ovarian cancer. Samples of ascitic fluid and/or solid biopsies were taken from 120 patients with FIGO stage III or IV ovarian adenocarcinoma at presentation. Cells were exposed for 48 hours to four concentrations of clinically relevant drugs including platinums, anthracyclines and alkylating agents. Cell survival was measured using the 3-4,5-dimethyl-2, 5-diphenyl tetrazolium bromide (MTT) assay allowing patients to be grouped as "sensitive" or "resistant" in vitro. Clinical data including age, residual disease, histological grade, treatment, response after initial treatment and overall survival were collected. There was a highly significant (p<0.0001) correlation of in vitro sensitivity with in vivo response in the patients who completed their therapy, with an 83% positive predictive accuracy for resistance. This translated in the longer term to an increased survival for the patients found to be sensitive in vitro to their therapy with a 5-year survival rate of 24% compared to 12% for the resistant group (p=0.033). These results suggest that MTT chemonsensitivity testing can predict response in ovarian cancer leading to the prospect of increased survival in this devastating disease by customising therapy to individual patients.

Prevalence of occupationally related hand dermatitis in dental workers.

Occupationally related hand dermatitis has been attributed to frequent hand-washing, exposure to possible sensitizers and latex glove use. The authors conducted a study to determine the prevalence of occupationally related hand dermatitis in dental personnel. They found that 75 (19.2 percent) of 390 subjects self-reported they had a positive history of hand dermatitis. Further testing of 53 of these subjects indicated that only 9.4 percent reacted to the 45 allergens tested, and 3.8 percent had an allergy to latex.

Lactobezoars: a patient series and literature review.

Lactobezoar is a compact mass of undigested milk concretions located within the gastrointestinal tract. Most often found in infants, they can precipitate gastric outlet obstruction, mimicking a variety of medical and surgical conditions. A common etiology and method of cure have yet to be elucidated. A review of the literature provides some insight into causes, clinical presentations, diagnosis, and management. Data from the Medical University of South Carolina further help dispel the belief that lactobezoars are isolated to pre-term infants on caloric-dense formulas. Findings suggest bezoar formation may be more common than previously thought and a high index of suspicion could help avoid costly evaluations for obstructive symptoms.

Considerations for inter-hospital extracorporeal cardiopulmonary support resuscitation and transport.

The availability of commercial, pre-packaged extracorporeal cardiopulmonary support (ECPS) circuits, which are simplified for rapid set-up and priming, has made the intra-hospital resuscitation of moribund patients routine. The successful utilization of this technology in the emergent setting requires planning and the coordination of personnel familiar with the technology. Many issues must be addressed when a patient requiring life-sustaining support utilizing this technology at an outlying hospital, must be transported while on ECPS. After reducing the size and weight of the ECPS cart and obtaining Federal Aviation Administration approval for use during aeromedical transport, the Emanuel Hospital Mobile Surgical Transport Team (MSTT) was able to extend the use of emergency cardiopulmonary bypass to outlying medical facilities. The patients selected for transport, using ECPS, are a group of patients with a potentially survivable pathology unlikely to survive inter-hospital transport without such measures. This report describes our experience with inter-hospital transport of patients on ECPS with special emphasis on transport considerations.