Characterization of volatile compounds in fermented milk using solid-phase microextraction methods coupled with gas chromatography-mass spectrometry.

Lactic acid bacteria (LAB) are industrially important bacteria that are widely used in the fermented food industry, especially in the manufacture of yogurt. Characteristic flavors are produced by LAB during fermentation and storage that affect the quality and acceptability of fermented milk products. In this study, the volatile compounds in milk fermented by Streptococcus thermophilus IMAU80842 alone, Lactobacillus delbrueckii ssp. bulgaricus IMAU20401 alone, or both species together were identified using solid-phase microextraction methods coupled with gas chromatography-mass spectrometry. A total of 53, 43, and 32 volatile compounds were identified in milk fermented by S. thermophilus alone, L. delbrueckii ssp. bulgaricus alone, or both species together, respectively. The presence of some important flavor compounds was confirmed: acetic acid, acetaldehyde, acetoin, 2,3-butanedione, ethanol, and 1-heptanol. Our results demonstrate that the composition of the volatile compounds in fermented milk depends on the species of LAB used and whether they are used alone or in combination. This is important for the selection of appropriate starter cultures for the production of different types of fermented milk product with particular flavors.

The 1996 and 1997 National survey of physician asthma management practices: background and study methodology.

OBJECTIVES: To collect national baseline information on asthma management practices by physicians, and to compare these practices with the recommendations of the Canadian Asthma Consensus Conference ('the guidelines'). DESIGN: Cross-sectional survey of representative samples of physicians in Canada in late 1996 and early 1997. POPULATION STUDIED: Five specialty types of physicians who manage asthma patients: respirology, pediatrics, internal medicine, allergy and clinical immunology, and general practice and family medicine. Stratified sampling by province and specialty was used to select physicians for the study. Weighting was used in the analysis to generalize the results to the national level for the five specialty groups of physicians. METHOD: Mailed questionnaire, self-administered by the respondent; three mailings of the questionnaires were used to increase the response rate. MAIN RESULTS: The frequency with which each of the five specialty types chose specific asthma management choices was determined, using weighted percentages representative of the specialty groups on a national basis. ANOVA determined the statistically significant differences among the five specialties in choosing particular asthma management actions. Then, logistic regression was used to calculate the odds ratios showing an association between the characteristics of the physician respondents and specific asthma management choices that they made in the survey. CONCLUSIONS: The data analysis demonstrated significant variations among physicians in asthma management practices, according to specialty type and other characteristics. The initial report was released in April 1998, and manuscripts for journal submissions are being prepared.

[Study on the Chinese drug beimu. IX. Microscopic identification of the upper epidermis of the scales of Fritillaria bulls].

Beimu, a famous traditional Chinese drug, has been used as an antitussive and expectorant for a long time and it is derived from a number of species of Fritillaria. So it is difficult to identify exactly the botanical origin of the commercial crude drugs by means of macroscopic examination. This paper deals with the microscopic identification of the upper epidermis of the scales of 20 species. The result showed that these species are different from each other in the shape and size of the epidermal cells, the shape, size and arrangement of the cuticular peg. Moreover, it was found that the anticlinal wall of the epidermal cells is not bead--thickened, but cuticular peg formed by cuticle.

[Pharmacognostical studies on Baibu radix stemonae and allied drugs. IX. Determination and evaluation of total alkaloid content in the roots of Chinese Stemona spp].

An acid-dye colorimetric method was reported for the determination of total alkaloids in 53 samples of Baibu drugs from their growing destricts in 14 provinces and municipalities and its average recovery and its linear range were 96.1% (CV less than 4%) and 20-150 micrograms respectively. The relationship between the total alkaloid content, geographical origins and morphology were discussed. The results showed that: 1. the content of total alkaloids of stemona was 0.26-3.1%; 2. that of Stemona sessilifolia was 0.26-2.17% with the highest content of the sample from Nanyang country in Henan Province; 3. that of S. japonica was 0.83-1.43%; 4. that of S. tuberosa was 0.53-3.1% with the highest content of sample from Hengyang in Hunan Province; 5. that of S. parviflora was 0.22-0.74% with the highest content of sample from Qongzhong in Hainan Province; and 6. that of more yellow, solider and stronger samples was higher than that of any other samples. However, that of all bigger samples in shape was not higher than that of smaller ones.

[Microscopical examination of leaf sheathes of the Chinese drug "Shihu", herba dendrobii].

"Shihu", a famous Chinese traditional drug, is used to replenish the vital essence of the lung and stomach, to clear up the excessive heat and to promote the secretion of the body fluid. The commercial crude drugs under the general name "Shihu" are mostly derived from a number of species of the genus Dendrobium. It is difficult to identify exactly the botanical origin of these crude drugs through macroscopical examination. In order to tackle this problem, the leaf sheathes of the stems of 16 species of the genus Dendrobium are examined microscopically and the characteristics of their epidermal cells and calcium oxalate crystals are compared. The diagnostic features found are proved to be useful for the identification of the botanical origin of commercial samples of the "Shihu". In this paper the microscopical characters of 16 Dendrobium species are described with illustration.

[A survey of commercial Chinese crude drug shasheng (radix Adenophorae and Glehniae)].

The commercial crude drug of Radix Adenophorae bought from 15 provinces and autonomous regions, and Radix Glehniae bought from 17 provinces and autonomous regions were surveyed. The original plants of 60 samples of Radix Adenophorae were identified as 9 species and 4 subspecies of genus Adenophora. The main species are Adenophora stricta, A. stricta subsp. sessilifolia, A. potaninii and A. hunanensis. Sixty two samples of Radix Glehniae were all identified as the roots of Glehnia littoralis.

The impact of unemployment on health: a review of the evidence.

OBJECTIVE: To review the scientific evidence supporting an association between unemployment and adverse health outcomes and to assess the evidence on the basis of the epidemiologic criteria for causation. DATA SOURCES: MEDLINE was searched for all relevant articles with the use of the MeSH terms "unemployment," "employment," "job loss," "economy" and a range of mortality and morbidity outcomes. A secondary search was conducted for references from the primary search articles, review articles or published commentaries. Data and definitions of unemployment were drawn from Statistics Canada publications. STUDY SELECTION: Selection focused on articles published in the 1980s and 1990s. English-language reports of aggregate-level research (involving an entire population), such as time-series analyses, and studies of individual subjects, such as cross-sectional, case-control or cohort studies, were reviewed. In total, the authors reviewed 46 articles that described original studies. DATA EXTRACTION: Information was sought on the association (if any) between unemployment and health outcomes such as mortality rates, specific causes of death, incidence of physical and mental disorders and the use of health care services. Information was extracted on the nature of the association (positive or negative), measures of association (relative risk, odds ratio or standardized mortality ratio), and the direction of causation (whether unemployment caused ill health or vice versa). DATA SYNTHESIS: Most aggregate-level studies reported a positive association between national unemployment rates and rates of overall mortality and mortality due to cardiovascular disease and suicide. However, the relation between unemployment rates and motor-vehicle fatality rates may be inverse. Large, census-based cohort studies showed higher rates of overall mortality, death due to cardiovascular disease and suicide among unemployed men and women than among either employed people or the general population. Workers laid off because of factory closure have reported more symptoms and illnesses than employed people; some of these reports have been validated objectively. Unemployed people may be more likely than employed people to visit physicians, take medications or be admitted to general hospitals. A possible association between unemployment and rates of admission to psychiatric hospitals is complicated by other institutional and environmental factors. CONCLUSIONS: Evaluated on an epidemiologic basis, the evidence suggests a strong, positive association between unemployment and many adverse health outcomes. Whether unemployment causes these adverse outcomes is less straightforward, however, because there are likely many mediating and confounding factors, which may be social, economic or clinical. Many authors have suggested mechanisms of causation, but further research is needed to test these hypotheses.

Opioid, calcium, and adrenergic receptor involvement in protopine analgesia.

The analgesic effect of protopine (Pro), an alkaloid isolated from Papaveraceae, was confirmed by tail-pinch and hot-plate tests when given sc 10-40 mg.kg-1, and 20-40 mg.kg-1 inhibited the spontaneous movements of mice. Pro 40 mg.kg-1 increased the sleeping rate, prolonged the sleeping duration, and shortened the sleeping latency in mice hypnotized by ip pentobarbital sodium 30 mg.kg-1. Pro 10-40 mg.kg-1 did not affect the inflammatory reaction induced by xylene and egg white. An icv injection of Pro 20-200 micrograms/mouse showed a remarkable analgesic effect in mice. The icv pretreatment of naloxone 2 micrograms blocked the analgesic effect completely. CaCl2 40 micrograms/mouse (ICV) or methotrexate 10 mg.kg-1 (ip), an agonist of Ca2+ channel, showed a complete blockade of the analgesia, while nifedipine 100 mg.kg-1(po), a blocker of Ca2+ channel, enhanced the analgesic effect. The ip pretreatment of reserpine 4 mg.kg-1 reduced the Pro analgesia. Phentolamine 10 mg.kg-1(ip), an alpha-adrenergic blocker, tended to weaken the analgesia, but propranolol 10 mg.kg-1(ip), a beta-blocker, did not affect it. These results suggest that Pro displays its analgesic effect mainly through the opioid and calcium systems and partly through the adrenergic mechanism.