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1.
1‐Benzyl‐4‐hydroxy[2‐14C]piperidine, a useful intermediate in labeled compound synthesis, was prepared from [14C]formaldehyde in high yield. The distribution pattern of 14C in the product is consistent with a mechanism involving reversible iminium ion formation and rapid equilibration of the iminium ion through a cationic aza‐Cope rearrangement. These steps precede the rate‐determining intramolecular cyclization step. SCH 351125 is a potent, selective CCR5 receptor antagonist with potential as a treatment for HIV infection. [14C]SCH 351125, required for metabolism studies, was prepared from 1‐benzyl‐4‐hydroxy[2‐14C]piperidine in six steps. [14C]SCH 351125 is a mixture of four atropisomers. Preparation of [14C]SCH 351125 besylate salt of the desired atropisomer pair is also described. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
2.
Previously unreported effects of tissue storage were recently observed in the authors' experimental magnetic resonance (MR) studies. To evaluate the effect of elapsed time after excision and storage temperature on tissue relaxation time measurements, tissue samples from the liver, pancreas, kidney, testis, spleen, and brain were obtained in rats. T1 and T2 were first measured within 5 minutes of excision, and between subsequent measurements, tubes were kept in a water bath at 40°C, at room temperature (28°C), or in an ice bath (4°C). Cellular and organellar integrity was assessed with electron microscopy and correlated with the MR findings. At 40°C (20-MHz spectrometer), the T1 of liver decreased from 280 msec ± 8 to 212 msec ± 10 during the first 60 minutes; the T1 of pancreas decreased from 276 msec ± 3 to 208 msec ± 2. Other tissues showed less than a 5% decrease in T1. T2 changes were smaller than T1 changes in all tissues. Electron microscopy of pancreatic acinar cells showed postmortem changes in mitochondria evolving over the first 60 minutes after death. Manganese loading experiments implicated mitochondrial manganese stores in the observed enhanced postmortem decrease in T1. This study calls into question reported relaxation time data for liver and pancreas. MR studies of excised tissues must account for time and temperature to prevent systematic experimental errors.  相似文献   
3.
Polymorphisms in xenobiotic metabolizing genes are associated with altered metabolism of carcinogens in acute leukemia (AL). This study applied two data mining approaches to explore potential interactions among P53 and xenobiotic metabolizing genes in 230 AL patients [131 acute myeloid leukemia (AML) and 99 acute lymphoblastic leukemia (ALL)] and 199 controls. Individually, none of the genotypes showed significant associations with AML risk. However, in ALL the CYP1A12A TC genotype was associated with increased risk (OR = 2.02; 95% CI = 1.14–3.58; P = 0.01), whereas the GSTM1 null genotype imparted reduced risk (OR = 0.55; 95% CI = 0.31–0.96; P = 0.03). In classification and regression tree analysis, combinations of GSTM1 present, CYP1A12C AA or GG, EPHX1 exon3 TC, and EPHX1 exon4 AA or GG genotype strongly enhanced the risk of AML (OR = 5.89; 95% CI = 1.40–26.62; P = 0.01). In ALL, combinations of CYP1A12A TT, P53 GG or CC and GSTP1 AG genotypes conferred the highest risk (OR = 4.19; 95% CI = 1.45–12.25; P = 0.004). In multifactor dimensionality reduction analysis, a four locus model (GSTP1, P53, EPHX1 exon3, and CYP1A12A) was the best predictor model for ALL risk. The association between this model and ALL risk remained true even at low prior probabilities of 0.01% (false positive report probability = 0.05). Interaction entropy interpretations of the best model of ALL revealed that two‐way interactions were mostly synergistic. These results suggest that high order gene–gene interactions play an important role in AL risk. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
4.
BACKGROUND & AIMS: Heat shock proteins (Hsps), induced by cell stress, are known to protect against cellular injury. Recent studies have indicated that Hsp60 expression, induced by exposure to water immersion stress, protects against pancreatitis induced by administration of supramaximal doses of cerulein in rats. However, the mechanisms responsible for this protection are not known. Methods: Rats were water-immersed for 3-12 hours. Pancreatitis was induced by cerulein administration. RESULTS: The results confirm that prior induction of Hsp60 expression by water-immersion stress significantly ameliorates the severity of cerulein-induced pancreatitis as judged by the markedly reduced degree of hyperamylasemia, pancreatic edema, and acinar cell necrosis. Water immersion also prevents the subcellular redistribution of cathepsin B from a lysosome-enriched fraction to a heavier, zymogen granule-enriched fraction that is known to occur in this model of pancreatitis. Intra-acinar cell activation of trypsinogen that occurs shortly after exposure to a supramaximally stimulating dose of cerulein both in vivo and in vitro is prevented by prior water-immersion stress and Hsp60 expression. The protection against pancreatitis that follows water-immersion stress is not caused by alterations of cholecystokinin receptors, because water immersion does not alter the typical biphasic amylase secretory response to stimulation with cerulein. CONCLUSIONS: Water-immersion stress induces Hsp60 expression, ameliorates cerulein-induced pancreatitis, and prevents intra-acinar cell activation of trypsinogen. We suggest that Hsp60 protects against cerulein-induced pancreatitis by preventing trypsinogen activation within acinar cells.  相似文献   
5.
The effects of hemorrhagic shock, aspirin, and ethanol on the biochemical and morphologic changes of experimental pancreatitis were evaluated. Pancreatitis was induced by infusing rats with a supramaximally stimulating dose (5 μg/kg/h) of caerulein. Hemorrhagic shock was established by removing sufficient blood to reduce mean arterial pressure by 30%, where it was maintained for 30 min. Aspirin (25 mg/kg) and ethanol (2 g/kg) were administered through an orogastric tube at 8-h intervals for 48 h. Hemorrhagic shock did not alter the degree of hyperamylasemia, pancreatic edema, cathepsin subcellular redistribution, or in vitro LDH leakage that characterize this model of pancreatitis. Hemorrhagic shock did, however, worsen the morphologic evidence of pancreatic injury. Administration of aspirin with ethanol did not alter the degree of hyperamy-lasemia, pancreatic edema, or subcellular cathepsin redistribution. Aspirin-ethanol pretreatment also did not alter the morphologic severity of pancreatitis.  相似文献   
6.
BACKGROUND AND AIM: Recent studies have indicated that prior thermal stress causes upregulation of heat shock protein 70 (HSP70) expression in the pancreas and protects against secretagogue induced pancreatitis. The mechanisms responsible for the protective effect are not known. Similarly, the effects of prior non-thermal stress on HSP70 expression and pancreatitis are not known. The current studies were designed to specifically address these issues. METHODS: In the current studies pancreatitis was induced by administration of a supramaximally stimulating dose of caerulein 12 hours after thermal stress and 24 hours after non-thermal (that is, beta adrenergic stimulation) stress. RESULTS: Both thermal and non-thermal stresses caused pancreatic HSP70 levels to rise and resulted in increased expression of HSP70 in acinar cells. Both forms of stresses protected against caerulein induced pancreatitis and prevented the early intrapancreatic activation of trypsinogen which occurs in this model of pancreatitis. CONCLUSIONS: These results suggest that both thermal and non-thermal stresses protect against pancreatitis by preventing intrapancreatic digestive enzyme activation and that HSP70 may mediate this protective effect.  相似文献   
7.
8.
Charcot Leyden crystals are colorless, hexagonal, bipyramidal crystals formed from aggregation of material from disintegrating eosinophils. Eosinophilic infiltrate along with the presence of Charcot Leyden crystals is an indirect evidence of parasitic infestation. Here, we report a case where fine‐needle aspiration cytology smears prepared from hepatic space occupying lesion showed numerous Charcot Leyden crystals along with eosinophilic infiltrate, indicating parasitic infection. Diagn. Cytopathol. 2015;43:392–394. © 2014 Wiley Periodicals, Inc.  相似文献   
9.
The global epidemic of cardiovascular diseases (CVDs) is spiraling upwards primarily due to a sharp rise in the low and middle income countries (LMICs) which are experiencing rapid health transition driven by socioeconomic, technological and lifestyle changes. LMICs currently face a double burden of communicable and non-communicable diseases, leading to competing claims of health conditions that vie for policy makers’ attention as public health priorities in a setting of limited resources, substantially high out-of-pocket expenditure and weak systems of healthcare delivery. Evidence from high income countries suggests that most CVDs are largely preventable as the major CVD risk behaviours including tobacco use, physical inactivity, unhealthy diet, harmful use of alcohol, are avoidable and modifiable. Effective and sustainable behaviour change strategies for LMICs would require low cost, affordable and scalable interventions. There is limited evidence from LMICs on effective interventions to prevent, control and manage CVDs in LMICs. The global guidelines and framework for addressing CVD calls for an urgent need to identify and assess contextually relevant and resource sensitive health care interventions augmented by policy actions. A combination of population based and high risk individual based strategies which are evidence based, cost-effective, feasible as well as scalable would reduce CVD mortality and its devastating impact in LMICs.  相似文献   
10.

Background

Foreign bodies embedded deep in facial tissues presents a challenge to maxillofacial surgeons. Approximately one third of all foreign bodies are missed during initial examination. After facial trauma foreign bodies like grit particles, wooden pieces, thorns, pebbles, glass particles may get embedded into deeper facial tissues which are detected only accidently either with the help of radiographs or at a later stage when patient presents with some signs & symptoms like pain, pus discharge, sinus formation etc. Trauma to maxillofacial region especially after road traffic accidents is one of major cause of embedment of foreign body, but many of these cases go unnoticed. This article contains 3 cases of foreign bodies embedded in facial tissues.

Conclusion

Proper initial examination of facial lacerations with thorough debridement is very essential for finding embedded foreign bodies. Foreign bodies embedded in deeper tissues are missed by surgeon eyes, so whenever in doubt radiographs must be advised to rule out presence of foreign bodies.  相似文献   
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