Changes in Polar Lipid Composition in Balsam Fir during Seasonal Cold Acclimation and Relationship to Needle Abscission.

Needle abscission in balsam fir has been linked to both cold acclimation and changes in lipid composition. The overall objective of this research is to uncover lipid changes in balsam fir during cold acclimation and link those changes with postharvest abscission. Branches were collected monthly from September to December and were assessed for cold tolerance via membrane leakage and chlorophyll fluorescence changes at -5, -15, -25, -35, and -45 °C. Lipids were extracted and analyzed using mass spectrometry while postharvest needle abscission was determined gravimetrically. Cold tolerance and needle retention each significantly (p < 0.001) improved throughout autumn in balsam fir. There were concurrent increases in DGDG, PC, PG, PE, and PA throughout autumn as well as a decrease in MGDG. Those same lipids were strongly related to cold tolerance, though MGDG had the strongest relationship (R2 = 55.0% and 42.7% from membrane injury and chlorophyll fluorescence, respectively). There was a similar, albeit weaker, relationship between MGDG:DGDG and needle retention (R2 = 24.3%). Generally, a decrease in MGDG:DGDG ratio resulted in better cold tolerance and higher needle retention in balsam fir, possibly due to increased membrane stability. This study confirms the degree of cold acclimation in Nova Scotian balsam fir and presents practical significance to industry by identifying the timing of peak needle retention. It is suggested that MGDG:DGDG might be a beneficial tool for screening balsam fir genotypes with higher needle retention characteristics.

Clinical care of the exposed infants of HIV-infected mothers.

Infants born to HIV-infected mothers are at risk for mother-to-child transmission of HIV. Since the beginning of the epidemic, medical advances have dramatically reduced transmission rates from the mother to the child. Clinical care of the HIV-exposed infant involves unique management considerations. Clinicians caring for these infants must be knowledgeable about postexposure antiretroviral prophylaxis, understand the HIV diagnostic testing necessary to determine the infant's HIV status, and be able to provide relevant anticipatory guidance. This article presents the pertinent management considerations needed for clinicians to provide optimal care to the HIV-exposed infant.

Ergonomic problems encountered by the surgical team during video endoscopic surgery.

BACKGROUND: The aim of this study is to analyze the problems related to the ergonomic conditions faced by video endoscopic surgical teams during video endoscopic surgery by means of a questionnaire. METHODS: A questionnaire was distributed to 100 medical personnel, from 8 different disciplines, who performed video endoscopic surgeries. Participants were asked to answer 13 questions related to physical, perceptive, and cognitive problems. RESULTS: Eighty-two questionnaires were returned. Although there were differences among the disciplines, participants assessment of various problems ranged from 32% to 72% owing to poor ergonomic conditions. CONCLUSIONS: As the problems encountered by the staff during video endoscopic surgery and the poor ergonomic conditions of the operating room affect the productivity of the surgical team and the safety and efficiency of the surgery, redesigning of the instruments and the operating room is required.

Helicobacter pylori prevalence among indigenous peoples of South America.

The seroprevalence of Helicobacter pylori among secluded Indian populations of South America was determined to gain insight into the evolutionary history and possible transmission patterns of the organism. Serum samples obtained from 1024 donors in 22 different villages were tested by enzyme-linked immunosorbent assay for immunoglobulin G antibodies, and the results were confirmed by Western blot. The overall seroprevalence was 92%: >80% of children tested positive by 3 years of age, the highest prevalence in populations studied to date. Comparison of H. pylori prevalence with that of herpes simplex virus type 1, which is known to be transmitted orally, demonstrated a linear correlation in their prevalence rates, suggesting that these pathogens share risk factors. However, H. pylori seroprevalence was consistently higher, indicating that additional routes of transmission exist and/or that the organism is more transmissible. Seroprevalence did not correlate with the length of contact with the outside world. These results suggest that H. pylori was indigenous to the South American Indians and was not introduced by contact with outsiders.

Effects of a medical emergency team on reduction of incidence of and mortality from unexpected cardiac arrests in hospital: preliminary study.

OBJECTIVES: To determine whether earlier clinical intervention by a medical emergency team prompted by clinical instability in a patient could reduce the incidence of and mortality from unexpected cardiac arrest in hospital. DESIGN: A non-randomised, population based study before (1996) and after (1999) introduction of the medical emergency team. SETTING: 300 bed tertiary referral teaching hospital. PARTICIPANTS: All patients admitted to the hospital in 1996 (n=19 317) and 1999 (n=22 847). INTERVENTIONS: Medical emergency team (two doctors and one senior intensive care nurse) attended clinically unstable patients immediately with resuscitation drugs, fluid, and equipment. Response activated by the bedside nurse or doctor according to predefined criteria. MAIN OUTCOME MEASURES: Incidence and outcome of unexpected cardiac arrest. RESULTS: The incidence of unexpected cardiac arrest was 3.77 per 1000 hospital admissions (73 cases) in 1996 (before intervention) and 2.05 per 1000 admissions (47 cases) in 1999 (after intervention), with mortality being 77% (56 patients) and 55% (26 patients), respectively. After adjustment for case mix the intervention was associated with a 50% reduction in the incidence of unexpected cardiac arrest (odds ratio 0.50, 95% confidence interval 0.35 to 0.73). CONCLUSIONS: In clinically unstable inpatients early intervention by a medical emergency team significantly reduces the incidence of and mortality from unexpected cardiac arrest in hospital.

Use of Granada medium to detect group B streptococcal colonization in pregnant women.

Direct inoculation onto Granada medium (GM) in plates and tubes was compared to inoculation into a selective Todd-Hewitt broth (with 8 microg of gentamicin per ml and 15 microg of nalidixic acid per ml) for detection of group B streptococci (GBS) in pregnant women with 800 vaginal and 450 vaginoanorectal samples. Comparatively, GM was found to be as sensitive as the selective broth for the detection of GBS in vaginal specimens and more sensitive than selective broth for the detection of GBS in vaginoanorectal samples (96 versus 82%). The use of GM improved the time to reporting of a GBS-positive result by at least 24 h and reduced the direct cost of screening. We have also found that the inconvenience of anaerobic incubation of GM plates can be avoided when a cover slide is placed upon the inoculum, because aerobic incubation in GM plates with cover slides causes GBS to develop the same pigmentation that it develops with incubation under anaerobic conditions. These data support the routine use of GM plates or tubes as a more accurate, easier, and cheaper method of identification of GBS-colonized women compared to the enrichment broth technique.