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1.
BACKGROUND Accurate detection of gastric infection by Helicobacter pylori(H.pylori) and premalignant lesions are important for effective provision of treatment,preventing the development of gastric neoplasia.Optical enhancement systems with optical magnification improved the identification of mucosal superficial and vascular patterns in patients with dyspepsia.AIM To evaluate an optical enhancement system with high-definition magnification,for diagnosis of normal gastric mucosa,H.pylori-associated gastritis,and gastric atrophy.METHODS A cross-sectional,nonrandomized study from November 2015 to April 2016 performed in a single-tertiary academic center from Ecuador.Seventy-two consecutive patients with functional dyspepsia according to the Rome III criteria,were tested for H.pylori using a stool antigen test and were assigned to an Hp+group or an Hp-control group.Esophagogastroduodenoscopy with highdefinition optical magnification and digital chromoendoscopy was performed,and patients were classified into 4 groups,in accordance to the microvasculararchitecture pattern of the mucosa.Interobserver and intraobserver agreement among operators were calculated.RESULTS Of the 72 participants,35 were Hp+ and 37 were Hp-.Among 10 patients with normal mucosal histology in biopsy samples,90% had a Type I pattern of microvascular architecture by endoscopy.Among participants with type IIa and type IIb patterns,significantly more were Hp+ than Hp-(32 vs 8),and most(31 out of 40) had histological diagnoses of chronic active gastritis.Two of the three participants with a histological diagnosis of atrophy had a type III microvascular pattern.The type I pattern predicted normal mucosa,type IIa–IIb predicted H.pylori infection,and type III predicted atrophy with sensitivities of 90.0%,91.4%,and 66.7%,respectively.The intraobserver and interobserver agreements had kappa values of 0.91 and 0.89,respectively.CONCLUSION High-definition optical magnification with digital chromoendoscopy is useful for diagnosis of normal gastric mucosa and H.pylori-associated gastritis with high accuracy,but further studies are needed to determine whether endoscopic diagnosis of gastric atrophy is feasible.  相似文献   
2.
The congenital muscular dystrophies (CMDs) are a heterogeneous group of autosomal recessive disorders. Approximately one half of cases diagnosed with classic CMD show primary deficiency of the laminin alpha2 chain of merosin. Complete absence of this protein is usually associated with a severe phenotype characterized by drastic muscle weakness and characteristic changes in white matter in cerebral magnetic resonance imaging (MRI). Here we report an 8-month-old Mexican female infant, from a consanguineous family, with classical CMD. Serum creatine kinase was elevated, muscle biopsy showed dystrophic changes, and there were abnormalities in brain MRI. Immunofluorescence analysis demonstrated the complete absence of laminin alpha2. In contrast, expression of alpha-, beta-, gamma-, and delta-sarcoglycans and dystrophin, all components of the dystrophin-glycoprotein complex, appeared normal. A homozygous C long right arrow T substitution at position 7781 that generated a stop codon in the G domain of the protein was identified by mutation analysis of the laminin alpha2 gene ( LAMA2). Sequence analysis on available DNA samples of the family showed that parents and other relatives were carriers of the mutation.  相似文献   
3.
Abstract

We report on a series of 48 patients, ages 74 to 20 year, with hypophyseal adenomas. Of these, 46 (96%) had secreting tumors, 3 had Cushing’s disease, 9 had somatotrophinomas, and 34 (29 females and 5 males) had prolactinomas. Thirty cases were diagnosed as intrasellar adenomas (62%) while the remaining eighteen (38%) presented extrasellar expansion. Of 9 acromegalic patients, 7 had typical clinical and biochemical features while 2 were exclusively prognatic with normal basal GH levels, but abnormal dynamic tests. Prolactinomas were npninvasive in women and faster growing and more extensive in men. Forty seven patients underwent surgery. Five of these required craniotomy and the rest were approached through the sphenoidal bone (TSf). Remission was achieved in Cushing’s disease, acromegaly, and female intrasellar prolactinomas. Larger tumors such as nonsecreting adenomas and male prolactinomas showed poor results after undergoing subtotal resections, with persistance of endocrinological disturbances. From our findings it appears that these tumors are not more aggressive in youths than in adults. Because there was a close relationship between tumor size, invasiveness, and the patients, final outcome, we conclude that early diagnosis and treatment is essential. Frequent complaints in adolescents such as irregular menses, retarded puberty, and growth disorders should be thoroughly investigated and not merely considered as transient or ‘functional’ [Neural Res 1998; 20: 415–417]  相似文献   
4.
ContextOlder adults with advanced cancer face uncertainty related to their disease and treatment.ObjectivesTo evaluate the associations of uncertainty with psychological health and quality of life (QoL) in older adults with advanced cancer.MethodsSecondary cross-sectional analysis of baseline data from a national clustered geriatric assessment trial. Patients 70 years and older with advanced cancer considering a new line of chemotherapy were recruited. We measured uncertainty using the modified nine-item Mishel Uncertainty in Illness Scale. Dependent variables included anxiety (Generalized Anxiety Disorder-7), depression (Generalized Depression Scale-15), distress (distress thermometer), QoL (Functional Assessment of Cancer Therapy—General), and emotional well-being (Functional Assessment of Cancer Therapy—General subscale). We used multivariate linear regression analyses to evaluate the association of uncertainty with each dependent variable. We conducted a partial least squares analysis with a variable importance in projection (VIP) plot to assess the contribution of individual variables to the model. Variables with a VIP <0.8 were considered less influential.ResultsWe included 527 patients (median age 76 years; range 70–96). In multivariate analyses, higher levels of uncertainty were significantly associated with greater anxiety (β = 0.11; SE = 0.04), depression (β = 0.09; SE = 0.02), distress (β = 0.12; SE = 0.02), as well as lower QoL (β = ?1.08; SE = 0.11) and emotional well-being (β = ?0.29; SE = 0.03); the effect sizes were considered small. Uncertainty items related to disease and treatment were most strongly associated with psychological health and QoL scores (all VIP >0.8).ConclusionUncertainty among older patients with advanced cancer is associated with worse psychological health and QoL. Tailored uncertainty management strategies are warranted.  相似文献   
5.
Breast density notification laws, passed in 19 states as of October 2014, mandate that patients be informed of their breast density. The purpose of this study is to assess the impact of this legislation on radiology practices, including performance of breast cancer risk assessment and supplemental screening studies. A 20‐question anonymous web‐based survey was emailed to radiologists in the Society of Breast Imaging between August 2013 and March 2014. Statistical analysis was performed using Fisher's exact test. Around 121 radiologists from 110 facilities in 34 USA states and 1 Canadian site responded. About 50% (55/110) of facilities had breast density legislation, 36% of facilities (39/109) performed breast cancer risk assessment (one facility did not respond). Risk assessment was performed as a new task in response to density legislation in 40% (6/15) of facilities in states with notification laws. However, there was no significant difference in performing risk assessment between facilities in states with a law and those without (p < 0.831). In anticipation of breast density legislation, 33% (16/48), 6% (3/48), and 6% (3/48) of facilities in states with laws implemented handheld whole breast ultrasound (WBUS), automated WBUS, and tomosynthesis, respectively. The ratio of facilities offering handheld WBUS was significantly higher in states with a law than in states without (p < 0.001). In response to breast density legislation, more than 33% of facilities are offering supplemental screening with WBUS and tomosynthesis, and many are performing formal risk assessment for determining patient management.  相似文献   
6.
7.
D-003 is a mixture of very-long-chain aliphatic acids with cholesterol-lowering and concomitant anti-platelet effects. The microsomal cytochrome P-450 system comprises a superfamily of proteins present in hepatic and extrahepatic tissues that is responsible for the metabolism of many drugs. The present study was undertaken to investigate the effects of D-003 on in vivo drug-metabolizing hepatic enzymes. Two experimental series (n = 6 animals/group) were performed. In the first series rats were randomly distributed in one control and two groups treated with D-003 at 1,000 and 2,000 mg/kg for 14 days. In the second one they were distributed in one control and three groups treated with D-003 (250, 500, and 1,000 mg/kg) for 6 months. All treatments were orally administered by gastric gavage. Control rats were orally treated only with acacia gum/water vehicle. The content of microsomal P-450, b (5) cytochromes, total sulfhydryl groups, nonprotein sulfhydryl groups, and protein-bound sulfhydryl groups as well as the activities of NADPH cytochrome c reductase, aminopyrine demethylase, dimethylnitrosamine N-demethylase, 7-ethoxyresorufin O-deethylation, 7-pentoxyresorufin O-depentylation, and cytosolic glutathione S-transferase were assessed. D-003 administered up to 2,000 mg/kg or 1,000 mg/kg during 14 days or 6 months did not affect the activities of the hepatic drug-metabolizing enzymes investigated. It is concluded that D-003 is not metabolized by the liver cytochrome system and that potential risk derived from drug-to-drug interactions between D-003 and concomitant drugs appears to be low.  相似文献   
8.
Galantamine, a mild acetylcholinesterase inhibitor and an allosteric ligand of nicotinic receptors, enhanced in a concentration-dependent manner the amplitude of purinergic twitch contractions of the electrically stimulated rat vas deferens (0.2 Hz, 1 ms, 60 V). Other acetylcholinesterase inhibitors also increased the twitches, showing a hierarchy of potencies of galantamine>physostigmine>tacrine>rivastigmine=donepezil. The potentiations seem to be unrelated to the ability to inhibit acetylcholinesterase, since the hierarchy of potencies to block the enzyme in vas deferens was tacrine>physostigmine>rivastigmine>donepezil>galantamine. Acetylcholine also increased the twitches; such effect was produced by a low range of concentrations of acetylcholine (10(-10)-10(-7) M). This facilitatory effect of acetylcholine on twitches was significantly potentiated by galantamine (10(-7)-10(-6) M), but not by rivastigmine or donepezil. A striking enhancement of twitches was also caused by charybdotoxin, a blocker of high-conductance Ca2+-activated K+ channels, and by 4-aminopyridine, a non-specific blocker of K+ channels; in addition, apamin, a blocker of small-conductance Ca2+-activated K+ channels, induced a lower potentiation. The antagonist mecamylamine (10(-7)-10(-6) M) reduced by 80% the potentiation by galantamine, indicating the involvement of nicotinic receptors. Therefore, it is suggested that, besides an inhibition of acetylcholinesterase, some additional mechanisms, such as blockade of Ca2+-dependent K+ channels, or activation of nicotinic receptors of nerve terminals, might be involved in twitch potentiation. These results are relevant in the context of the clinical use of galantamine to improve cognition and behaviour in patients with Alzheimer's disease.  相似文献   
9.
羊膜培养液抑制角膜新生血管的实验研究   总被引:28,自引:1,他引:27  
Ma X  Bazan H  Li J 《中华眼科杂志》2003,39(12):753-756
目的 研究羊膜培养液对小鼠角膜新生血管的抑制作用及机制。方法 应用cornealmicropocket方法 ,将含 10 0ng碱性成纤维细胞生长因子 (bFGF)和 12 %hydronpolymer的缓释颗粒植入角膜层间 ,制备小鼠角膜新生血管模型。实验分对照组、羊膜组和去上皮羊膜组 ,每组 10只眼 ,收集各组培养液于模型制作当日起 ,每日滴眼 4次至术后 7d摄片观测角膜新生血管长入情况并处死动物。对脐静脉血管内皮细胞 (HUVEC)进行体外培养 ,并应用Boyden小房技术和荧光结合(CyQUANT)实验分别检测羊膜培养液对HUVEC细胞迁移和细胞增殖的影响。利用酶联免疫吸附(ELISA)法检测各组培养液中金属蛋白酶抑制剂 1(TIMP1)和 2 (TIMP2 )的含量。结果 羊膜培养液明显抑制由bFGF诱发的小鼠角膜新生血管的形成 ,对照组、羊膜组和去上皮羊膜组角膜新生血管面积分别是 (2 4 8± 0 76 )mm2 、(0 6 4± 0 5 2 )mm2 和 (1 96± 0 6 5 )mm2 。羊膜培养液明显抑制血管内皮细胞的迁移和增殖 ,而对照组和去上皮羊膜组对HUVEC细胞迁移无作用。羊膜培养液中TIMP2水平明显增高 ,而TIMP1的含量无变化。结论 羊膜培养液中TIMP1的含量未增加。而羊膜上皮产生或释放大量的TIMP2 ,抑制血管内皮细胞的迁移和增殖 ,其可能是羊膜培养液抑制角膜新生血管的  相似文献   
10.
Preeclampsia, a common complication of pregnancy, is characterized by elevated blood pressure and proteinuria developing after 20 weeks' gestational age. Susceptibility to this syndrome is believed to have a genetic component. The aim of this study was to investigate whether or not the 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T and glutathione S-transferase P1 (GSTP1) A313G polymorphisms are associated with preeclampsia in Maya-Mestizo women. A case-control study was performed, in which 125 preeclamptic patients and 274 healthy controls were genotyped for the MTHFR C677T and GSTP1 A313G polymorphisms by real-time PCR allelic discrimination. Allele and genotype frequencies were compared using the chi2 tests. The MTHFR 677T allele and the 677TT genotype were significantly more frequent in the controls, suggesting an association with a decreased risk of preeclampsia (p = 0.017 and p = 0.007, respectively). Similarly, GSTP1 313GG/GC genotypes and the G allele were more frequent in controls, showing a significant association with reduced risk of preeclampsia (p = 0.008 and p = 0.013, respectively). Our results suggest, for the first time, that the MTHFR 677T and GSTP1 313G polymorphisms confer a significantly decreased risk of developing preeclampsia in the Mexican Maya-Mestizo population.  相似文献   
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