In Vitro Reversible Transformation of Leishmania braziliensis panamensis Between Promastigote and Ellipsoidal Forms1

Raising the temperature of a log-phase culture of Leishmania braziliensis panamensis promastigotes from 26°C to 34°C resulted in formation of a culture containing 85% ellipsoidally shaped forms after 1.5 h. The temperature-induced ellipsoidal forms decreased in size but persisted in high proportion (85–95%) for at least 12 h at 34°C. Recovery from the ellipsoidal forms to a culture containing 85–95% promastigotes was observed after returning the temperature to 26°C. The time required for recovery increased markedly with the duration of the preceding heat treatment, up to about 70 h for a 12-h heat treatment.     

Screening tests for diabetes detection; combined with a chest x-ray survey

A program was carried out to test the value and feasibility of performing blood sugar screening tests in conjunction with a community-wide chest x-ray survey. A simple, rapid and inexpensive blood sugar screening test requiring only about two drops of blood from the finger tip was used. Among 14,681 persons who stated that they did not have diabetes, 191 or 1.3 per cent had "positive" results in screening tests. The number of persons referred to their physicians for diagnostic study because of the possibility of diabetes was reduced from 191 to 127 by means of a more specific secondary screening test. Diagnostic information with regard to 102 of the 127 persons referred to their physicians was supplied by the physicians. In 58 (0.40 per cent of the 14,681 participants) the diagnosis was diabetes-newly discovered as a result of referral by the survey.Some of the persons referred to their physicians because of suspicion of diabetes, while not then diabetic, might be considered prediabetic. The appearance of diabetes in this group during the year following the survey was therefore investigated. Glucose tolerance tests were performed for 32 of the diabetes suspects whose diagnosis immediately following the survey was either "not diabetic" or unknown. In 15 cases the glucose tolerance curves were indicative of diabetes, in seven cases questionable and in ten cases normal. The 58 persons diagnosed immediately after the survey plus the 15 found to have "diabetic" glucose tolerance curves a year later made a total of 73 newly discovered diabetics. This is a discovery rate of 0.50 per cent among the 14,681 participants in the survey. The success of this combined diabetes detection and chest x-ray survey suggests that other screening procedures should be studied to determine the desirability of adding them to similar community-wide case-finding programs.     

Hes1 Increases the Invasion Ability of Colorectal Cancer Cells via the STAT3-MMP14 Pathway

The Notch pathway contributes to self-renewal of tumor-initiating cell and inhibition of normal colonic epithelial cell differentiation. Deregulated expression of Notch1 and Jagged1 is observed in colorectal cancer. Hairy/enhancer of split (HES) family, the most characterized targets of Notch, involved in the development of many cancers. In this study, we explored the role of Hes1 in the tumorigenesis of colorectal cancer. Knocking down Hes1 induced CRC cell senescence and decreased the invasion ability, whereas over-expression of Hes1 increased STAT3 phosphorylation activity and up-regulated MMP14 protein level. We further explored the expression of Hes1 in human colorectal cancer and found high Hes1 mRNA expression is associated with poor prognosis in CRC patients. These findings suggest that Hes1 regulates the invasion ability through the STAT3-MMP14 pathway in CRC cells and high Hes1 expression is a predictor of poor prognosis of CRC.     

Characterization of microsatellite loci in the European green crab (Carcinus maenas)

Carcinus maenas (Decapoda: Portunidae) has proven a highly successful invasive marine species whose potential economic and ecological impacts are of great concern worldwide. Here, we characterize 14 polymorphic microsatellite loci in C. maenas and its sister species Carcinus aestuarii. These markers will prove useful for fine‐scale genetic analyses of native and introduced populations, for assessment of the sources and routes of invasion and for evaluation of post‐invasion population dynamics.     

Is stimulation of leaf photosynthesis by elevated carbon dioxide concentration maintained in the long term? A test with Lolium perenne grown for 10 years at two nitrogen fertilization levels under Free Air CO2Enrichment (FACE)

Photosynthesis is commonly stimulated in grasslands with experimental increases in atmospheric CO₂ concentration ([CO₂]), a physiological response that could significantly alter the future carbon cycle if it persists in the long term. Yet an acclimation of photosynthetic capacity suggested by theoretical models and short‐term experiments could completely remove this effect of CO₂. Perennial ryegrass (Lolium perenne L. cv. Bastion) was grown under an elevated [CO₂] of 600 µmol mol^?1 for 10 years using Free Air CO₂Enrichment (FACE), with two contrasting nitrogen levels and abrupt changes in the source : sink ratio following periodic harvests. More than 3000 measurements characterized the response of leaf photosynthesis and stomatal conductance to elevated [CO₂] across each growing season for the duration of the experiment. Over the 10 years as a whole, growth at elevated [CO₂] resulted in a 43% higher rate of light‐saturated leaf photosynthesis and a 36% increase in daily integral of leaf CO₂ uptake. Photosynthetic stimulation was maintained despite a 30% decrease in stomatal conductance and significant decreases in both the apparent, maximum carboxylation velocity (V_c,max) and the maximum rate of electron transport (J_max). Immediately prior to the periodic (every 4–8 weeks) cuts of the L. perenne stands, V_c,max and J_max, were significantly lower in elevated than in ambient [CO₂] in the low‐nitrogen treatment. This difference was smaller after the cut, suggesting a dependence upon the balance between the sources and sinks for carbon. In contrast with theoretical expectations and the results of shorter duration experiments, the present results provide no significant change in photosynthetic stimulation across a 10‐year period, nor greater acclimation in V_c,max and J_max in the later years in either nitrogen treatment.