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31.
Adnexal torsion is the fifth most common gynecologic surgical emergency, requiring clinician and radiologist awareness. It involves the rotation of the ovarian tissue on its vascular pedicle leading to stromal edema, hemorrhagic infarction, and necrosis of the adnexal structures with the subsequent sequelae. Expedient diagnosis poses a difficult challenge because the clinical presentation is variable and often misleading. Adnexal torsion can mimic malignancy as it can take a subacute, intermittent, or chronic course, and thereby can be complicated to diagnose. The torsion may occur in the normal ovary but is usually secondary to a preexisting adnexal mass. Early surgery is necessary to avoid irreversible adnexal damage and to preserve ovarian function especially in children and young women. Pelvic ultrasound forms the foundation of diagnostic evaluation due to its ability to directly and rapidly evaluate both ovarian anatomy and perfusion. Moreover, it is a noninvasive and accessible technique. However, the color Doppler appearance of the ovary should not be relied upon to rule out torsion because a torsed ovary or adnexa may still have preserved arterial flow due to the dual blood supply. MR and CT may be used as problem-solving tools needed after the ultrasound examination but should not be the first-line imaging modalities in this setting due to ionizing radiation and potential time delay in diagnosis. The goal of this article is to review the adnexal anatomy, to familiarize radiologists with the main imaging features, and to discuss the main mimickers and the most common pitfalls of adnexal torsion. Main points
  • Adnexal torsion is an uncommon gynecological disorder caused by partial or complete rotation of the ovary and/or the Fallopian tube about the infundibulopelvic ligament.
  • The ovaries receive a dual blood supply from the ovarian artery and uterine artery.
  • The lack of pathognomonic symptoms and specific findings on physical examination makes this entity difficult to diagnose. Since the right adnexa are most commonly involved, symptoms may mimic acute appendicitis.
  • Persistence of adnexal vascularization does not exclude torsion.
  • In the pediatric age group, gray-scale ultrasound is the best modality of choice. Obtaining CT and/or MR images should not delay treatment in order to preserve ovarian viability.
  相似文献   
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Microcystin-LR and -LA were readily biodegraded by a bacterium, Sphingpoyxis sp. LH21, in a treated reservoir water. Detection of the microcystins was conducted using high-performance liquid chromatography (HPLC), protein phosphatase 2A (PP2A) inhibition assay and a cell-based cytotoxicity assay. The HPLC results correlated well with the two assays. The decrease in cytotoxicity, coupled with the associated decrease in microcystin concentrations, indicated that no cytotoxic by-products were being generated, highlighting the applicability of biodegradation as a feasible treatment option for effective microcystin removal.  相似文献   
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Neuroinflammation constitutes a normal part of the brain immune response orchestrated by microglial cells. However, a sustained and uncontrolled production of proinflammatory factors together with microglial activation contribute to the onset of a chronic low-grade inflammation, leading to neuronal damage and cognitive as well as behavioral impairments. Hence, limiting brain inflammatory response and improving the resolution of inflammation could be particularly of interest to prevent these alterations. Dietary n-3 long chain polyunsaturated fatty acids (LC-PUFAs) and low molecular weight peptides are good candidates because of their immunomodulatory and proresolutive properties. These compounds are present in a fish hydrolysate derived from marine-derived byproducts. In this study, we compared the effect of an 18-day supplementation with this fish hydrolysate to a supplementation with docosahexaenoic acid (DHA) on lipopolysaccharide (LPS)-induced inflammation in mice. In response to peripherally injected LPS, the fish hydrolysate supplementation decreased the hippocampal mRNA expression of the proinflammatory cytokines IL-6 (p < 0.001), IL-1β (p = 0.0008) and TNF-α (p < 0.0001), whereas the DHA supplementation reduced only the expression of IL-6 (p = 0.004). This decline in proinflammatory cytokine expressions was associated with an increase in the protein expression of IκB (p = 0.014 and p = 0.0054 as compared to the DHA supplementation and control groups, respectively) and to a modulation of microglial activation markers in the hippocampus. The beneficial effects of the fish hydrolysate could be due in part to the switch of the hippocampal oxylipin profile towards a more anti-inflammatory profile as compared to the DHA supplementation. Thus, the valorization of fish byproducts seems very attractive to prevent and counteract neuroinflammation.  相似文献   
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Bioactive diterpenes from the fruits of Detarium microcarpum   总被引:1,自引:0,他引:1  
A fruit pulp extract of Detarium microcarpum showed inhibition of the growth of the plant pathogenic fungus Cladosporium cucumerinum and of the enzyme acetylcholinesterase, implicated in Alzheimer's disease. Fractionation of this extract led to the isolation of four new clerodane diterpenes, 3,4-epoxyclerodan-13E-en-15-oic acid (1), 5alpha,8alpha(2-oxokolavenic acid) (2), 3,4-dihydroxyclerodan-13E-en-15-oic acid (4), and 3,4-dihydroxyclerodan-13Z-en-15-oic acid (5). Also isolated were 2-oxokolavenic acid (3) and copalic acid (6). Structure elucidation of the compounds was carried out by spectroscopic data interpretation and by the X-ray crystallography of 2 and 4. Three of the new clerodane diterpenes (1, 2, and 5) showed both antifungal activity and inhibition of acetylcholinesterase, and 3 showed a slight inhibition of this enzyme.  相似文献   
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