This review is focused on describing the use of magnetic resonance (MR) spectroscopy for metabolic imaging of brain tumors. We will first review the MR metabolic imaging findings generated from preclinical models, focusing primarily on in vivo studies, and will then describe the use of metabolic imaging in the clinical setting. We will address relatively well‐established 1H MRS approaches, as well as 31P MRS, 13C MRS and emerging hyperpolarized 13C MRS methodologies, and will describe the use of metabolic imaging for understanding the basic biology of glioma as well as for improving the characterization and monitoring of brain tumors in the clinic. 相似文献
It is essential for malariologists and researchers to have simple and accurate means of assessing the threat of Plasmodium parasites. An attempt was therefore made to re-standardize one of the circumsporozoite (CS) ELISA that can be used to detect and quantify the circumsporozoite antigens of P. falciparum and P. vivax. A two-site, 'sandwich' ELISA based on a monoclonal antibody was used to test for the CS antigen and sporozoites of each Plasmodium species simultaneously. Using the resultant optical-density values, standard curves, that permit the number of sporozoites in an infected mosquito to be estimated from the quantification of the CS antigen, were constructed. Using these plots and the CS ELISA, the presence of just 12.5 sporozoites (i.e. 0.8 pg CS antigen) of P. falciparum, four sporozoites (3.2 pg antigen) of P. vivax-210 or 12.5 sporozoites (32.0 pg antigen) of P. vivax-247 could be demonstrated. 相似文献
The insulin-like growth factor I receptor (IGF-IR) is expressed in many cell types and is critical for normal growth and development.
In the healthy mammary gland, the role of IGF-IR is not fully elucidated. However, IGF-IR, which is primarily expressed in
the mammary epithelial cells, is known to play an obligatory role in cellular transformation, facilitating the progression
to breast cancer. We have utilized the tetracycline regulatory (tet-on) system to generate an in vitro model system to allow
us to further investigate IGF-I/IGF-IR function in mammary epithelial cells. A plasmid construct containing a mutant IGF-I
receptor (IGF-IR-DN) fused to the tetracycline operator (tetOPhCMV-IGF-IR-DN) was stably transfected into MCF-7 human breast cancer cells. The conditional regulation of the IGF-IR-DN gene
expression was studied in four independent clonal lines. The translated IGF-IR-DN protein was detected only in the stably
transfected doxycycline-induced cells, and its expression was up-regulated (three- to sixfold) following induction. IGF-I
stimulated cell proliferation diminished (twofold) in doxycycline-induced cells compared to uninduced cells, demonstrating
that the transgene construct was functional and ruling out any pleiotropic effect that may be attributed to doxycycline. Interestingly,
autophosphorylation of the IGF-IR and phosphorylation of the downstream substrate, insulin receptor substrate-1 (IRS-1), was
not inhibited in doxycycline/IGF-I treated cells, suggesting the possibility that activation of downstream substrates other
than the IRS-1 may be critical for optimal cell proliferation. This novel in vitro model should allow us to more directly
examine the role of IGF-I/IGF-IR signaling and function in mammary epithelial cells. 相似文献
Cockroach allergy has been recognized as an important cause of asthma. Exposure to high levels of cockroach allergens in the
home is a major risk factor for symptoms in sensitized individuals. Previously identified allergens from Blatella germanica and Periplaneta americana include Bla g 2 (inactive aspartic proteinase), Bla g 4 (calycin), Bla g 5 (glutathione-S-transferase), Bla g 6 (troponin),
the Group 1 cross-reactive allergens Bla g 1 and Per a 1, Per a 3 (arylphorin), and Per a 7 (tropomyosin). The primary site
of cockroach allergen accumulation is the kitchen. However, lower levels of allergen can be found in bedding, on the bedroom
floor, and in sofa dust. Strategies for decreasing exposure to cockroach have been investigated. The results suggest that
a sustained decrease in cockroach allergen levels is difficult to accomplish, even after successful extermination of cockroach
populations. The use of recombinant cockroach allergens may lead to the development of new approaches to asthma treatment
in the future. 相似文献
Context: Opioids represent a drug class that adolescents and young adults intentionally misuse and abuse. When taken on their own or with other substances in this manner, opioids pose an increased risk of overdose and potential death.
Objective: To determine trends of opioid drug poisonings among adolescents and young adults in Ohio from 2002 to 2014 using Poison Control Center (PCC) data.
Methods: Data were obtained from Ohio PCCs from 2002 to 2014 for opioid drug poisonings amongst 10–29 year olds. Trends were evaluated with Poisson regression. Ohio counties with higher opioid drug poisoning rates were identified using age-adjusted resident population estimates. Chi-square tests were conducted to compare these county rates to the Ohio rate.
Results: Both unintentional and intentional Ohio PCC opioid drug poisonings peaked in 2009, and there were significant declines through 2014. Almost 40% of intentional opioid drug poisonings were for young adults aged 18–24 years. Suspected suicide poisonings were 64.9% female, misuse poisonings were 54.5% male, and abuse poisonings were 60.1% male. Commonly reported substances included tramadol, heroin, and acetaminophen combinations with hydrocodone or oxycodone. Benzodiazepines and ethanol were the most common substances reported in conjunction with opioids. The top four Ohio counties with significantly higher opioid drug poisoning rates than the state average in 2014 were Hamilton, Mahoning, Butler, and Fairfield.
Conclusion: This study enhances the understanding of Ohio’s opioid epidemic so that future prevention efforts and legislation can better target needed resources. Both males and females would benefit from opioid education early in their lives. 相似文献