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81.
Melanoma-associated retinopathy is a rare paraneoplastic neurological syndrome characterized by retinopathy in melanoma patients. The main photoreceptor proteins have been found to be expressed as cancer-retina antigens in melanoma. Here we present evidence that these can function as paraneoplastic antigens in melanoma-associated retinopathy. Sera and one tumor cell line of such patients were studied and ret-transgenic mice spontaneously developing melanoma were used as a murine model for melanoma-associated retinopathy. Splenocytes and sera were used for adoptive transfer from tumor-bearing or control mice to wild-type mice. Retinopathy was investigated in mice by funduscopy, electroretinography and eye histology. Expression of photoreceptor proteins and autoantibodies against arrestin and transducin were detected in melanoma-associated retinopathy patients. In tumor-bearing ret-transgenic mice, retinopathy was frequently (13/15) detected by electroretinogram and eye histology. These pathological changes were manifested in degenerations of photoreceptors, bipolar cells and pigment epithelium as well as retinal detachment. Mostly these defects were combined. Cancer-retina antigens were expressed in tumors of these mice, and autoantibodies against arrestin were revealed in some of their sera. Adoptive transfer of splenocytes and sera from tumor-bearing into wild-type mice led to the induction of retinopathy in 4/16 animals. We suggest that melanoma-associated retinopathy can be mediated by humoral and/or cellular immune responses against a number of cancer-retina antigens which may function as paraneoplastic antigens in melanoma-associated retinopathy.  相似文献   
82.
83.
IgG is the most prominent marker of post-COVID-19 immunity. Not only does this subtype mark the late stages of infection, but it also stays in the body for a timespan of at least 6 months. However, different IgG subclasses have different properties, and their roles in specific anti-COVID-19 responses have yet to be determined. We assessed the concentrations of IgG1, IgG2, IgG3, and IgG4 against different SARS-CoV-2 antigens (N protein, S protein RBD) using a specifically designed method and samples from 348 COVID-19 patients. We noted a statistically significant association between severity of COVID-19 infection and IgG concentrations (both total and subclasses). When assessing anti-N protein and anti-RBD IgG subclasses, we noted the importance of IgG3 as a subclass. Since it is often associated with early antiviral response, we presumed that the IgG3 subclass is the first high-affinity IgG antibody to be produced during COVID-19 infection.  相似文献   
84.
Five new triterpene glycosides, liouvillosides A1 (1), A2 (2), A3 (3), B1 (4), and B2 (5), have been isolated from the Antarctic sea cucumber Staurocucumis liouviellei along with the known liouvilloside A(6), isolated earlier from the same species, and hemoiedemosides A (7) and B (8), isolated earlier from the Patagonian sea cucumber Hemioedema spectabilis. The isolation was carried out using a new chromatographic procedure including application of ion-pair reversed-phase chromatography followed by chiral chromatography on a cyclodextrin ChiraDex column. The structures of the new glycosides were elucidated using extensive NMR spectroscopy (1H and 13C NMR spectrometry, DEPT, 1H-(1)H COSY, HMBC, HMQC, and NOESY), ESI-FTMS, and CID MS/MS, and chemical transformations. Glycosides 1-3 are disulfated tetraosides and glycosides 4 and 5 are trisulfated tetraosides. Glycosides 2 and 3 contain 3-O-methylquinovose, found for the first time as a natural monosaccharide in sea cucumber glycosides. On the basis of analyses of glycoside structures a taxonomic revision is proposed.  相似文献   
85.
The review presents the data accumulated for more than 20 years of research of torque teno virus(TTV). Its molecular genetic structure, immunobiology,epidemiology, diagnostic methods, possible replication sites, and pathogenicity factors are described. TTV is a virus that is frequently detectable in patients with different viral hepatitides, in cases of hepatitis without an obvious viral agent, as well as in a healthy population. There is evidence suggesting that biochemical and histological changes occur in liver tissue and bile duct epithelium in TTV monoinfection. There are sufficient histological signs of liver damage, which confirm that the virus can undergo a replicative cycle in hepatocytes. Along with this, cytological hybridization in TTV-infected cells has shown no substantial cytopathic(cell-damaging) effects that are characteristic of pathogenic hepatotropic viruses. Studying TTV has led to the evolution of views on its role in the development of human pathology. The first ideas about the hepatotropism of the virus were gradually reformed as new data became available on the prevalence of the virus and its co-infection with other viruses, including the viruses of the known types of hepatitides. The high prevalence of TTV in the human population indicates its persistence in the body as a virome and a nonpathogenic virus. It has recently been proposed that the level of TTV DNA in the blood of patients undergoing organ transplantation should be used as an endogenous marker of the body's immune status. The available data show the polytropism of the virus and deny the fact that TTV can be assigned exclusively to hepatitis viruses. Fortunately, the rare detection of the damaging effect of TTV on hepatic and bile duct epithelial cells may be indirect evidence of its conditionally pathogenic properties. The ubiquity of the virus and the variability of its existence in humans cannot put an end to its study.  相似文献   
86.
The paper deals with drug abuse in minors who are on the records of the regional surgery for toxicomania in Ostrava-Poruba. The authors give an account of examinations of 27 children aged 7.5 to 14 years. They emphasize the social and psychological aspects leading in these children to drug abuse. They present the basic four types of children who incline to failure in this respect: markedly extrovert subjects with good intellect, markedly submissive children, more introvert subjects with inferior intellect, neglected children with poor intellect and behavioural disorders and children with a high appetence for the drug. In the conclusion the authors emphasize possibilities of prevention within the discipline of psychiatry.  相似文献   
87.
Whey protein hydrolysates (WPHs) are one of the most promising sources of biofunctional peptides with such beneficial properties as antioxidant, antihypertensive, anti-inflammatory and others. WPHs also could be used as foaming agents for aerated products (e.g., milk shake type drinks). However, WPH alone has a bitter taste and foamed WPH should be stabilized by additional ingredients. Here, we present a composition including WPH and three polysaccharides—pumpkin pectin, sodium alginate and ι-carrageenan—used as foam stabilizers. Polysaccharide content was selected according to foaming, organoleptic antioxidant and angiotensin-I-converting enzyme inhibitory characteristics of the resulted composition. Further, the hypotensive, antioxidant and hepatoprotective properties of the composition were proved by in vivo tests performed in spontaneously hypertensive rats and Wistar rats with CCl4-induced hepatic injury.  相似文献   
88.

Objective

To develop criteria for safe and oncologically satisfying liver resection in case of early hepatocellular carcinoma with a 5-year overall survival (OS) similar to liver transplantation.

Summary background data

Liver resection (LR) and liver transplantation (LT) are potentially curative treatment options for hepatocellular carcinoma. Generally, LT achieves better OS. Due to organ shortage, however not all patients can receive a LT.

Methods

To decide which patients to resect and which to transplant we have developed biological resection criteria (BRC) as a compound out of mGPS (modified Glascow Prognostic Scale) and the Kings-Score (for HCV cirrhosis). These are based on routine clinical values that reflect both liver function and tumor biology/immunology.

Results

276 patients were analyzed. Patients undergoing LR within BRC (inBRC) had a significantly better overall (73.6% vs. 35.4%, (p?<?0.001)) and disease-free survival (54.7% vs. 17.2%, (p?<?0.001)) as compared to patients outside the BRC (outBRC). The predictive value of BRC was independent of tumor burden. In a subgroup analysis outBRC patients had significantly worse outcome after major resection. In LT patients BRC had no predictive value.

Conclusions

BRC may be a valuable tool to predict survival after LR for HCC. Patients resected inBRC may achieve comparable survival as LT. LR in outBRC patients are unlikely to be curative. All outBRC patients should be monitored closely for salvage LT.  相似文献   
89.
The synthesis of -aminocaproic acid esters is described. Two representative members from a group of five of the 1-alkyl homologues synthetized as flexible analogues of 1-alkylazacycloheptanone derivatives were evaluated in vitro for their effectiveness on the transport of theophylline through the excised human cadaver skin in comparison with Azone. The 1-octyl- and 1-dodecyl--aminocaproic acid esters (OCEAC and DDEAC) show excellent penetration enhancement. Donor samples contained 2.5% theophylline and 1% enhancers tested in three different vehicles. Fluxes of theophylline were increased with OCEAC about 19 times from olive oil, 45 times from water, and about 38 times from water–propylene glycol (3:2) vehicle toward controls (with DDEAC about 17, 39, and 35 times, respectively) and they were markedly higher than Azone under the given conditions. Acute LD50's (i.p. in mice) of OCEAC (DDEAC) were 245 mg/kg (352 mg/kg), with a slightly lower toxicity than Azone. OCEAC and DDEAC did not exhibit acute dermal irritation in vivo on rabbits at a 5% concentration in white petrolatum.  相似文献   
90.
This case report describes a 35-year-old woman who was diagnosed with mixed epithelial/mesenchymal metaplastic carcinoma (carcinosarcoma) of the breast. Genetic analysis of blood DNA revealed a common founder mutation, BRCA1 5382insC. Examination of microdissected tumor samples determined that both epithelial and mesenchymal components contained deletion of the wild-type BRCA1 allele. This report exemplifies that even very uncommon breast tumor types may develop through biallelic inactivation of BRCA1 gene, that has to be considered in the genetic testing settings.  相似文献   
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