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191.
Globally, many insect populations are declining, prompting calls for action. Yet these findings have also prompted discussion about sampling methods and interpretation of long‐term datasets. As insect monitoring and research efforts increase, it is critical to quantify the effectiveness of sampling methods. This is especially true if sampling biases of different methods covary with climate, which is also changing over time. We assess the effectiveness of two types of flight intercept traps commonly used for beetles, a diverse insect group responsible for numerous ecosystem services, under different climatic conditions in Norwegian boreal forest. One of these trap designs includes a device to prevent rainwater from entering the collection vial, diluting preservatives and flushing out beetles. This design is compared to a standard trap. We ask how beetle capture rates vary between these traps, and how these differences vary based on precipitation levels and beetle body size, an important species trait. Bayesian mixed models reveal that the standard and modified traps differ in their beetle capture rates, but that the magnitude and direction of these differences change with precipitation levels and beetle body size. At low rainfall levels, standard traps catch more beetles, but as precipitation increases the catch rates of modified traps overtake those of standard traps. This effect is most pronounced for large‐bodied beetles. Sampling methods are known to differ in their effectiveness. Here, we present evidence for a less well‐known but likely common phenomenon—an interaction between climate and sampling, such that relative effectiveness of trap types for beetle sampling differs depending on precipitation levels and species traits. This highlights a challenge for long‐term monitoring programs, where both climate and insect populations are changing. Sampling methods should be sought that eliminate climate interactions, any biases should be quantified, and all insect datasets should include detailed methodological metadata.  相似文献   
192.

Background  

Mycobacterium avium includes the subspecies avium, silvaticum, paratuberculosis and hominissuis, and M. avium subspecies has been isolated from various environments all over the world including from biofilms in water distribution systems. The aim of this study was to examine isolates of M. avium subsp. avium and M. avium subsp. hominissuis of different origin for biofilm formation and to look for correlations between biofilm formation and RFLP-types, and to standardise the method to test for biofilm formation. In order to determine the best screening method, a panel of 14 isolates of M. avium subsp. avium and M. avium subsp. hominissuis, were tested for their ability to form biofilm in microtiter plates under different conditions. Subsequently, 83 additional isolates from humans, swine and birds were tested for biofilm formation. The isolates were tested for the presence of selected genes involved in the synthesis of glycopeptidolipids (GPLs) in the cell wall of M. avium, which is believed to be important for biofilm formation. Colony morphology and hsp65 sequvar were also determined.  相似文献   
193.

Background  

Neisseria meningitidis, the causative agent of meningococcal disease, is exposed to high levels of reactive oxygen species inside its exclusive human host. The DNA glycosylase Fpg of the base excision repair pathway (BER) is a central player in the correction of oxidative DNA damage. This study aimed at characterizing the meningococcal Fpg and its role in DNA repair.  相似文献   
194.

Background

Prospective studies have indicated that elevated blood glucose levels may be linked with increased cancer risk, but the strength of the association is unclear. We examined the association between blood glucose and cancer risk in a prospective study of six European cohorts.

Methods and Findings

The Metabolic syndrome and Cancer project (Me-Can) includes cohorts from Norway, Austria, and Sweden; the current study included 274,126 men and 275,818 women. Mean age at baseline was 44.8 years and mean follow-up time was 10.4 years. Excluding the first year of follow-up, 18,621 men and 11,664 women were diagnosed with cancer, and 6,973 men and 3,088 women died of cancer. We used Cox regression models to calculate relative risk (RR) for glucose levels, and included adjustment for body mass index (BMI) and smoking status in the analyses. RRs were corrected for regression dilution ratio of glucose. RR (95% confidence interval) per 1 mmol/l increment of glucose for overall incident cancer was 1.05 (1.01–1.10) in men and 1.11 (1.05–1.16) in women, and corresponding RRs for fatal cancer were 1.15 (1.07–1.22) and 1.21 (1.11–1.33), respectively. Significant increases in risk among men were found for incident and fatal cancer of the liver, gallbladder, and respiratory tract, for incident thyroid cancer and multiple myeloma, and for fatal rectal cancer. In women, significant associations were found for incident and fatal cancer of the pancreas, for incident urinary bladder cancer, and for fatal cancer of the uterine corpus, cervix uteri, and stomach.

Conclusions

Data from our study indicate that abnormal glucose metabolism, independent of BMI, is associated with an increased risk of cancer overall and at several cancer sites. Our data showed stronger associations among women than among men, and for fatal cancer compared to incident cancer. Please see later in the article for the Editors'' Summary  相似文献   
195.
cAMP mediates its intracellular effects through activation of protein kinase A (PKA), nucleotide-gated ion channels, or exchange protein directly activated by cAMP (Epac). Although elevation of cAMP in lymphocytes leads to suppression of immune functions by a PKA-dependent mechanism, the effector mechanisms for cAMP regulation of immune functions in monocytes and macrophages are not fully understood. In this study, we demonstrate the presence of Epac1 in human peripheral blood monocytes and activation of Rap1 in response to cAMP. However, by using an Epac-specific cAMP analog (8-CPT-2'-O-Me-cAMP), we show that monocyte activation parameters such as synthesis and release of cytokines, stimulation of cell adhesion, chemotaxis, phagocytosis, and respiratory burst are not regulated by the Epac1-Rap1 pathway. In contrast, activation of PKA by a PKA-specific compound (6-Bnz-cAMP) or physiological cAMP-elevating stimuli like PGE(2) inhibits monocyte immune functions. Furthermore, we show that the level of Epac1 increases 3-fold during differentiation of monocytes into macrophages, and in monocyte-derived macrophages cAMP inhibits FcR-mediated phagocytosis via both PKA and the Epac1-Rap1 pathway. However, LPS-induced TNF-alpha production is only inhibited through the PKA pathway in these cells. In conclusion, the Epac1-Rap1 pathway is present in both monocytes and macrophages, but only regulates specific immune effector functions in macrophages.  相似文献   
196.
While newly developed technologies have revolutionized the classical approaches to combating infectious diseases, the difficulties associated with developing novel antimicrobials mean that these technologies have not yet been used to introduce new compounds into the market. The new technologies, including genomics and structural biology, open up exciting possibilities for the discovery of antibiotics. However, a substantial effort to pursue research, and moreover to incorporate the results into the production chain, is required in order to bring new antimicrobials to the final user. In the current scenario of emerging diseases and the rapid spread of antibiotic resistance, an active policy to support these requirements is vital. Otherwise, many valuable programmes may never be fully developed for lack of "interest" and funds (private and public). Will we react in time to avoid potential disaster?  相似文献   
197.
198.
Summary Cytorhodin-S, an anthracycline derivative, was covalently coupled to a monoclonal antibody (mAb) CA208, against carcinoembryonic antigen (CEA) in order to achieve selective killing of a CEA-producing colon carcinoma cell line, COLO 205. The conjugate (15 molecules of drugs/antibody) retained substantial antibody activity as well as drug activity as assessed by enzyme-linked immunosorbent assay and 24-h L1210 proliferation assay, respectively. Furthermore, the conjugate inhibited the growth of COLO 205 cells in a short-term cytostatic assay. This cytostatic effect of the immunoconjugate on COLO 205 cells was inhibited in a dose-dependent manner by pretreatment of the cells with unconjugated CA208 mAb. In addition, chloroquine, a lysosomotropic agent, inhibited the cytostatic effect of the immunoconjugate, indicating the involvement of lysosomal enzymes in releasing drugs from the immunoconjugate. The antibody (CA208) was significantly incorporated into the cytoplasm of COLO 205 cells as demonstrated by immuno-electron microscopy. These in vitro results indicate that cytorhodin-S may be a good partner in immunoconjugates. However, in vivo animal experiments with the immunoconjugate revealed that the immunoconjugate was not so effective in prolonging survival. Thus, in vivo efficacy of this immunoconjugate remains to be further improved in application to cancer immunotherapy.  相似文献   
199.
Preliminary evidence suggests that theory of mind and empathy relate differentially to factors of schizotypy. The current study assessed 686 undergraduate students and used structural equation modeling to examine links between a four-factor model of schizotypy with performance on measures of theory of mind (Reading the Mind in the Eyes Test [MIE]) and empathy (Interpersonal Reactivity Index [IRI]). Schizotypy was assessed using three self-report measures which were simultaneously entered into the model. Results revealed that the Negative factor of schizotypy showed a negative relationship with the Empathy factor, which was primarily driven by the Empathic Concern subscale of the IRI and the No Close Friends and Constricted Affect subscales of the Schizotypal Personality Questionnaire. These findings are consistent with a growing body of literature suggesting a relatively specific relationship between negative schizotypy and empathy, and are consistent with several previous studies that found no relationship between MIE performance and schizotypy.  相似文献   
200.
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