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41.
42.
A 23-year-old man had an 8-day history of fatigue and dry cough and papulo-nodular reactions on his extensive tattoos. Chest radiography revealed several small granular shadows, and a transbronchial lung biopsy showed non-caseating epithelioid cell granuloma. A skin biopsy of the tattooed area showed histiocytic infiltrates with phagocytized tattoo pigment. Antibody tests for hepatitis C virus were positive. The patient was successfully treated with corticosteroid therapy, and after inflammation was suppressed, he received delayed anti-viral therapy. Sarcoidosis should be considered as a concurrent condition if papules are presented on the tattoos of patients with hepatitis C.  相似文献   
43.
Mak  Lung-Yi  Huang  Qi  Wong  Danny Ka-Ho  Stamm  Luisa  Cheung  Ka-Shing  Ko  Kwan-Lung  Yan  Ran  Ouyang  Lea  Fung  James  Seto  Wai-Kay  Yuen  Man-Fung 《Journal of gastroenterology》2021,56(5):479-488
Journal of Gastroenterology - We aimed to assess whether residual hepatitis B virus (HBV) viraemia is associated with HCC development. This is a case–control study of 104 patients [52 HCC and...  相似文献   
44.
超过60%的胃神经内分泌肿瘤(gastric neuroendocrine neoplasms,G-NENs)内镜下病变表现为多发病灶,可为息肉样隆起、黏膜下来源的肿瘤,或为丘疹、糜烂、溃疡性病灶,病变多局限于黏膜层或黏膜下层,病灶多数<10 mm,平均5 mm。1型G-NENs中,约22%病例内镜下并无任何肉眼可见的病灶,只有通过胃体、胃底的盲检,显微镜下才能发现病灶,即微小类癌。本例患者胃镜下并无任何肉眼可见的隆起型病灶,因一次随机活检,才得以发现病变。本文结合该例病变内镜下表现及其临床特征,以提升诊断G-NENs的经验。  相似文献   
45.
Insulin-like growth factors-I and -II (IGF-I and -II) are structurally related mitogenic polypeptides with potent growth promoting effects. These peptides and their corresponding IGF-I and -II receptors are selectively localized in the brain. To date, most of the effects of IGFs are believed to be mediated by IGF-I receptors whereas the significance of IGF-II receptor in mediating biological responses remains unclear. In the present study, we characterized the distribution of IGF-I and IGF-II receptor sites and investigated the effects of both factors on endogenous acetylcholine (ACh) release in adult rat hippocampus. [125I]IGF-I receptor binding sites are recognized by IGF-I> IGF-II> insulin, whereas [125I]IGF-II binding was competed potently by IGF-II> IGF-I but not by insulin. At the cellular level, IGF-I receptor sites were primarily noted in the molecular layer of the dentate gyrus and the CA2-CA3 subfields of the Ammon’s horn whereas IGF-II sites were localized predominantly in the pyramidal cell layer of the CA1-CA3 subfields and in the granular cell layer of the dentate gyrus. IGF-I (10−14–10−8 M) and des(1–3) IGF-I (10−10–10−8 M) were found to inhibit whereas IGF-II (10−14–10−8 M) potentiated K+-evoked ACh release from hippocampal slices. Tetrodotoxin altered the effects of IGF-I but not those of IGF-II suggesting that IGF-I acts indirectly via the release of other modulators whereas IGF-II acts directly on or in close proximity to the cholinergic terminals. The inhibitory effects of IGF-I were also observed in the frontal cortex but not in the striatum. In contrast, the stimulatory effects of IGF-II were evident both in the frontal cortex and striatum. Taken together, these results reveal the differential localization of IGF-I and IGF-II receptor sites in the hippocampal formation and the opposite role for these growth factors in the acute regulation of ACh release likely via two distinct mechanisms. Additionally, these data provide the first evidence for a direct role for IGF-II and its receptors in the regulation of transmitter release in the central nervous system.  相似文献   
46.
Changes in sodium-22 turnover and total body potassium (TBK) were studied during acute (within 2 weeks after clipping) and chronic (12-14 weeks after clipping) phases in two-kidney, one-clip (2k, 1c) hypertensive rabbits by using a whole body counter. Sodium-22 injected intravenously was eliminated more rapidly in hypertensive rabbits than in controls. The biological half-life (BHL) of sodium-22 was shorter in hypertensive rabbits during both acute (p less than 0.05) and chronic phases (p less than 0.001). A significant negative correlation was obtained between the BHL of sodium-22 and blood pressure (r = -0.588, p less than 0.05) in hypertensive rabbits. TBK decreased significantly at the chronic phase in hypertensive rabbits (p less than 0.05), while TBK showed no significant change in controls. Serum sodium and potassium did not change during the observation period. Increased plasma aldosterone concentration was observed during the acute phase in hypertensive rabbits. These results suggested that sodium retention was not a major factor in the acute and chronic phases of 2k, 1c hypertension in rabbits and that pressure natriuresis could explain, at least in part, the lack of sodium retention. Furthermore, there appears to be a derangement in the intracellular potassium metabolism which may be associated with the maintenance rather than the development of hypertension.  相似文献   
47.
Purpose

JWH-424, (8-bromo-1-naphthyl)(1-pentyl-1H-indol-3-yl)methanone, is a synthetic cannabinoid, which is a brominated analogue of JWH-018, one of the best-known synthetic cannabinoids. Despite the structural similarity to JWH-018, little is known about JWH-424 including its metabolism. The aim of the study was to compare human liver microsomes (HLM) and the fungus Cunninghamella elegans as the metabolism catalysts for JWH-424 to better understand the characteristic actions of the fungus in the synthetic cannabinoid metabolism.

Methods

JWH-424 was incubated with HLM for 1 h and Cunninghamella elegans for up to 72 h. The HLM incubation mixtures were diluted with methanol and fungal incubation mixtures were extracted with dichloromethane and reconstituted in methanol before analyses by liquid chromatography–high-resolution mass spectrometry (LC-HRMS).

Results

HLM incubation resulted in production of ten metabolites through dihydrodiol formation, hydroxylation, and/or ipso substitution of the bromine with a hydroxy group. Fungal incubation led to production of 23 metabolites through carboxylation, dihydrodiol formation, hydroxylation, ketone formation, glucosidation and/or sulfation.

Conclusions

Generally, HLM models give good predictions of human metabolites and structural analogues are metabolised in a similar fashion. However, major hydroxy metabolites produced by HLM were those hydroxylated at naphthalene instead of pentyl moiety, the major site of hydroxylation for JWH-018. Fungal metabolites, on the other hand, had undergone hydroxylation mainly at pentyl moiety. The metabolic disagreement suggests the necessity to verify the human metabolites in authentic urine samples, while H9 and H10 (hydroxynaphthalene), H8 (ipso substitution), F22 (hydroxypentyl), and F17 (dihydroxypentyl) are recommended for monitoring of JWH-424 in urinalysis.

  相似文献   
48.
Urinary bile acids from 20 patients treated with chenodeoxycholate, 18 treated with ursodeoxycholate, 15 treated with rifampicin and 8 patients with advanced cirrhosis were analyzed by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry. Occurrence rates and amounts of three so-called unusual trihydroxy bile acids, hyocholate, ursocholate and omega-muricholate, were increased in patients treated with chenodeoxycholate, ursodeoxycholate or rifampicin and decreased in cirrhotic patients as compared with those in untreated healthy adults. These data suggest that chenodeoxycholate and ursodeoxycholate are hydroxylated to produce unusual trihydroxy bile acids in bile acid-loaded humans and that this metabolism may be related to the induction of hepatic microsomal enzymes by rifampicin. In contrast, the hydroxylation of chenodeoxycholate and ursodeoxycholate may be impaired by severe hepatic damage. Because the urine is a secretory pathway for internal bile acids, the occurrence of unusual trihydroxy bile acids in the urine may be used as an indicator of hepatic ability to metabolize "hydrophobic" dihydroxy bile acids to their secretory forms.  相似文献   
49.
BACKGROUND: Oxidative stress plays a role in the development of chronic peripheral arterial disease (PAD) because under these conditions redox regulation is impaired, inducing the S-glutathionylation of proteins. A method of estimating the levels of S-glutathionylated proteins has been developed using biotinylated glutathione S-transferase, which allows the study of their crucial role in the oxidative stress-related progression of PAD. METHODS AND RESULTS: The serum levels of S-glutathionylated proteins were examined in 41 patients with arteriosclerosis obliterans (ASO) and 38 age-matched non-ASO patients using biotinylated glutathione S-transferase. The levels were higher in the patients with ASO, even early on, and positively correlated with the ankle/brachial index. In vitro, the levels of S-glutathionylated proteins were reduced in the presence of glutathione and glutaredoxin. CONCLUSIONS: Serum levels of S-glutathionylated proteins are a sensitive risk-marker for ASO at an early stage.  相似文献   
50.
The biologic, serologic, and molecular properties of isolates of human immunodeficiency virus type 1 (HIV-1) from the central nervous system (CNS) were determined and compared to those of isolates from peripheral blood and lymph nodes. Among these were pairs of CNS and blood isolates obtained from six infected individuals. The data show that HIV-1 isolates from the CNS can be distinguished from peripheral blood isolates by their (i) relative inability to infect established T-cell lines, (ii) reduced cytopathogenicity, (iii) inability to modulate CD4 antigen expression on infected cells, (iv) efficient replication in peripheral blood macrophages, and (v) insensitivity to serum neutralization. Paired CNS and peripheral blood isolates from the same individual also display some differences in cellular tropism. The blood isolates replicate better in T-cell lines and glioma cell lines, whereas the paired CNS isolates replicate more efficiently in primary macrophages. These results suggest that viruses isolated from the CNS of infected individuals may represent a specific HIV-1 subgroup.  相似文献   
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