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111.
Since the late 1950s, reports on an unusual giant-cell granulomatous lesion affecting the jaws, lungs, stomach and intestines have been published . Histopathologically, the lesions showed the presence of structureless hyaline rings with multinucleated giant cells. The aim of this review was to summarize the literature on the etiopathogenesis of the so-called oral and extraoral pulse or hyaline ring granuloma. Literature was searched using PubMed and Medline. In addition, hand search was performed. Search words were oral and extraoral hyaline ring granuloma, giant-cell hyaline angiopathy, pulse granuloma and chronic periostitis. Numerous terms for hyaline ring granuloma have been introduced over time (1971–2008). One hundred seventy-three cases of oral hyaline ring granuloma have been retrieved from the literature. In the mandible, 72.3% occurred . Two theories for etiopathogenesis have been proposed: (1) the origin of the hyaline rings is due to a foreign material (pulse and legumes) having penetrated the oral mucosa or gastrointestinal tract and lungs (exogenous theory) and (2) the rings are due to hyaline degenerative changes in walls of blood vessels (endogenous theory). Experimental production of oral and extraoral hyaline ring granulomas is consistent with the exogenous origin. Particles or remains of leguminous cells having been implanted or aspirated into human tissues whether located to the oral cavity or throughout the entire digestive tract and respiratory system are thought to be causative. Pulse or hyaline ring granulomas are rare but are well-defined oral and extraoral lesions due to implantation of the cellulose moiety of plant foods in contrast to the starch components.  相似文献   
112.
We assessed the use of peptides containing arginylglycylaspartic acid (RGD) that target integrin αvβ6 as a potential approach for a fluorescence-assisted intraoperative cytological assessment of bony resection margins (F-AICAB) in patients who had bone-infiltrating squamous cell carcinoma (SCC) of the head and neck. This was assessed to demarcate invasive carcinoma cells that stained for αvβ6. Specimens from bony resection margins (n=362) were defined as either malignant or benign according to the results of cytological and histological examinations. Integrin αvβ6-targeting fluorescence-labelled RGD peptides were added to the cytological samples and the accuracy of the resulting signal assessed by comparing it with the cytological findings. The value of F-AICAB was evaluated to find out if it could help to improve future diagnoses, tests, and treatments. Integrin αvβ6 was strongly expressed in invasive SCC cells and qualified as a marker for bone-infiltrating carcinoma cells. It showed a high affinity to bind to invasive SCC cells and enabled swift and specific demarcation of αvβ6-stained carcinoma cells. It was also diagnostic, with a sensitivity of 100% (95% CI 81.3% to 99.3%), specificity of 98.3% (95% CI 94.4% to 99.0%), positive predictive value of 92% (95% CI 70.2% to 94.3%), and negative predictive value of 100% (95% CI 96.9% to 99.9%), compared with the cytological findings. The targeting of specific integrin subtypes with selective, synthetic ligands, adapted for multimodal imaging, is a promising new approach to diagnosis. Further studies are necessary to provide more evidence for successful clinical translation and to establish the impact on clinical procedures.  相似文献   
113.
Allotransplantation is the therapy of choice for endstage diseases. Due to the organ shortage, three times respectively twice as many patients are currently waiting for kidneys or hearts as are actually transplanted annually in Germany. Consequently, the mortality rate on the heart transplant list is around 16%; if patients have to wait more than 24 months for a kidney, the graft survival after 10 years will be less than half when compared to those who are able to receive an organ within 6 months. Therefore, porcine xenotransplantation of kidneys and hearts will be a very much needed alternative clinical technique – including (porcine) xenogenic islet cell transplantation for diabetic patients with hypoglycaemic attacks – a large number of persons, if one considers that the number of people suffering from diabetes worldwide increased by nearly 50% over the last decade. Of course, much more work is needed before clinical xenotransplantation will become a safe and long lasting alternative. The α(1,3)‐galactosyltransferase KO, PERV C free pigs – held in specific pathogen free units – must express several human transgenes, like a complement regulator molecule (in order to suppress non Gal‐AB's) and HLA‐E (protection from NK‐cell cytotoxicity). Some kind of accommodation will be necessary (e.g. via Hemoxygenase‐1 or PDL‐1 – a negative costimulatory receptor which also increases the CD4+ CD25high Fox p3+ subset). An overexpression of thrombomodulin (TM) would finally be necessary in order to overcome the disparity between porcine (TM) and human (Thrombin) proteins and possibly avoid microvascular thrombotic disease. And to top all these desires of a clinical transplant specialist, all the genetic engineering should be achieved in close connection within one chromosome, preferably an artificial one, in order to make all these changes hereditary. The just mentioned strategies are the main topics of the DFG‐Transregio Research Group. The following abstracts will highlight the respective progress and will also inevitably evaluate arising problems. International leaders in our field will give their results and opinion – an interchange which is necessary within the small but very active xenotransplantation research field. It is my sincere belief that a clinical scenario of xenotransplantation will be possible in the near future.  相似文献   
114.
ObjectiveTo investigate the potentials of the root bark of Annona (A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.MethodsThe methanol extract (ME) of the root bark of A. senegalensis was studied in mice using pentylenetetrazole (PTZ) induced convulsions, phenobarbitone induced sleeping time and motor coordination test on rota-rod performance. Acute toxicity and lethality (LD50) test as well as phytochemical analysis were also carried out.ResultsThe extract (200, 400, 800 mg/kg) exhibited a non-dose dependent significant (P <0.05) delay in the onset of both tonic and clonic phases of seizure induced by PTZ (60 mg/kg, s.c.) as well as offered a 100% protection (200 mg/kg) in mice from PTZ induced seizures. The extract significantly (P <0.05) decreased the latency and increased the duration of phenobarbitone induced sleeping time. At 200 mg/kg, the extract exhibited a significant (P <0.05) motor incoordination. The acute toxicity test revealed an oral LD50 of 1 296 mg/kg, while the phytochemical studies showed the presence of alkaloids, resins, glycosides, carbohydrate, reducing sugar, flavonoids, terpenoids, saponins and tannins.ConclusionThe extract of A. senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects.  相似文献   
115.
We have read the recent comprehensive review by Cruz et al.[1] regarding the targeting of receptor tyrosine kinases andtheir therapeutic perspectives in head and neck squamous cellcarcinomas (HNSCC). The major focus of this report was epidermalgrowth factor receptor (EGFR) biology and targeting. However,we feel  相似文献   
116.
BACKGROUND: Studies are inconsistent as to whether patients with bipolar disorder are more frequently affected by autoimmune thyroiditis. AIM: To study the prevalence of autoimmune thyroiditis in offspring of bipolar patients. METHOD: In 1998 140 children (age 12-21 years) of bipolar parents were evaluated psychiatrically using the K-SADS-PL and blood was drawn to determine thyroperoxidase antibodies (TPO-Abs) and serum TSH. Blood samples of high school students (aged 12-19 years, n=77) and young adults (aged 20-35 years, n=52) were used as comparisons. At follow-up the offspring were psychiatrically evaluated and tested for TPO-Abs and TSH twice (14 months and 55 months after enrollment). RESULTS: TPO-Abs were predominantly found in female bipolar offspring, who had a significantly higher prevalence of positive TPO-Ab titers (9 out of 57 female offspring subjects) as compared to the female high school and young adult comparisons (4 out of 103 female control subjects). In TPO-Ab positive offspring (n=11) a raised prevalence of 55% of thyroid failure (i.e. a raised serum TSH or l-thyroxine treatment) was evident. TPO-Ab positive offspring did not show a raised prevalence of mood disorders (or any psychopathology) as compared to the TPO-Ab negative offspring. CONCLUSION: Our study suggests that bipolar offspring are more vulnerable to develop thyroid autoimmunity independently from the vulnerability to develop psychiatric disorders.  相似文献   
117.
The aim of this study was to measure plasma atrial natriuretic peptide in preterm infants with a patent ductus arteriosus before and after closure with indomethacin. Atrial natriuretic peptide was measured in 28 preterm infants with clinical and echocardiographic evidence of a patent ductus arteriosus and in eight preterm infants who did not develop clinical evidence of a patent ductus arteriosus. Plasma concentration of atrial natriuretic peptide was measured by radioimmunoassay. In 18 infants the patent ductus arteriosus closed after one course of indomethacin; atrial natriuretic peptide levels decreased from median 1240 pg/ml (range 201-5483 pg/ml) to 266 pg/ml (range 62-1108 pg/ml). In four infants the patent ductus arteriosus closed after two courses of indomethacin and two infants had surgical ligation after indomethacin treatment failed. The patent ductus arteriosus closed spontaneously in four infants (atrial natriuretic peptide median level 152 pg/ml, range 61-495 pg/ml). In the eight infants without patent ductus arteriosus, atrial natriuretic peptide level was median 224 pg/ml (range 38-876 pg/ml). Measurement of plasma atrial natriuretic peptide concentration has a role in predicting when indomethacin treatment is indicated.  相似文献   
118.
119.
Precancerous conditions are defined as a generalized state associated with a significantly increased risk of cancer. For the oral and perioral region, sideropenic dysphagia, oral lichen planus (OLP), oral submucous fibrosis (OSF), syphilis, discoid lupus erythematosus, xeroderma pigmentosum as well as epidermolysis bullosa play a role as precancerous conditions. The number of published cases of oral or perioral malignant transformation for some of these diseases is small. In addition, carcinomas of the tongue and the oral cavity associated with syphilis are of historical interest, although publications in the 1990s still reported positive serology of syphilis and carcinomas of the tongue. OLP is still controversially discussed as to its premalignant nature. Transformation rates have been reported between 0% and 5.6%. Recent prospective studies have revealed that possibly oral lichenoid reactions (OLR) are more likely to form the basis of malignant transformation as compared to the classic OLP. The differentiation between OLP and OLR is difficult both from clinical and histopathological aspects. The second most important precancerous condition is oral submucous fibrosis, which is caused by betel quid chewing. OSF is most prevalent in South and Southeast Asia. The transformation rate is as high as 7.6% making OSF one of the most important precancerous conditions of the oral region.   相似文献   
120.
Female rats do not exhibit free fatty acid-induced insulin resistance   总被引:10,自引:0,他引:10  
Hevener A  Reichart D  Janez A  Olefsky J 《Diabetes》2002,51(6):1907-1912
It is well described that excessive lipid metabolism can cause insulin resistance in both animals and humans, and this has been implicated as a causative factor in the development of insulin resistance and type 2 diabetes in humans. Recently, we have shown that intravenous lipid emulsion (liposyn) infusion during a 120-min euglycemic-hyperinsulinemic clamp led to significant reductions in insulin action and fatty acid translocase (FAT/CD36) skeletal muscle protein expression. After reviewing the literature, it became evident that essentially all past studies, including our own, were conducted in male animals. Therefore, to determine whether there were sex determinants of fat-induced insulin resistance, we assessed the impact of free fatty acid (FFA) elevation on insulin action in female rats. Here, we report that a fourfold elevation in plasma FFA concentration induced a 40% reduction in the insulin-stimulated glucose disposal rate, a 30% decline in insulin-stimulated skeletal muscle insulin substrate receptor-1 (IRS-1) phosphorylation, a 48% decrease in IRS-1-associated phosphatidylinositol (PI) 3-kinase activity, and a 50% reduction in muscle FAT/CD36 protein expression in male rats. In striking contrast, we found no effect of FFA elevation to cause insulin resistance, changes in IRS-1/PI 3-kinase, or FAT/CD36 protein levels in female animals. Our findings indicate that female animals are protected from lipid-induced reductions in insulin action.  相似文献   
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