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J M Rhodes  R R Black  R Gallimore    A Savage 《Gut》1985,26(12):1312-1318
Experiments were carried out to assess the susceptibility of normal and inflammatory bowel disease rectal mucus to desulphation and desialation by faecal extracts and by bacterial sialidase. The effects were assessed histochemically using a combined high iron diamine (HID) and alcian blue (AB) stain for sulphomucins and sialomucins. Rectal mucus in biopsies from controls (irritable bowel syndrome) and patients with ulcerative colitis or Crohn's disease was resistant to desialation by Clostridium perfringens sialidase, but susceptible to desialation and desulphation by bacteria-free extracts of normal faeces. Periodic acid-Schiff (PAS) staining of adjacent sections similarly treated showed retention of neutral mucus. One faecal extract selectively desulphated all 42 biopsies, causing the goblet cells to change from HID positive to AB positive, suggesting that most, or all HID positive cells also contain sialomucins. This alters the interpretation of previous histochemical studies. Faecal extracts from patients with active ulcerative colitis (n = 6) had desialating and desulphating effects similar to faecal extracts from normal subjects (n = 6). Ulcerative colitis (n = 21), Crohn's disease (n = 18), and control (irritable bowel syndrome) (n = 17) rectal biopsies all showed similar susceptibility to desulphation by a pooled normal faecal extract, but rectal biopsies from patients with Crohn's disease proved more resistant to desialation than control or ulcerative colitis biopsies (p less than 0.02). These studies imply that colonic mucus undergoes continual desulphation and desialation in vivo as a result of faecal enzyme activity that is probably mainly of bacterial origin. Altered susceptibility of colonic mucus to this may be important in the pathogenesis of colonic disease.  相似文献   
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Objectives. We examined Hispanic men’s recent risky and protective sexual behaviors with female partners by acculturation.Methods. Using the 2006–2010 National Survey of Family Growth, we performed bivariate analyses to compare acculturation groups (Hispanic Spanish-speaking immigrants, Hispanic English-speaking immigrants, Hispanic US natives, and non-Hispanic White men) by demographics and recent sexual behaviors with women. Multivariable logistic regression models for sexual behaviors by acculturation group were adjusted for demographics.Results. Compared with Hispanic Spanish-speaking immigrants, non-Hispanic White men were less likely to report exchange of money or drugs for sex (adjusted odds ratio [AOR] = 0.3; 95% confidence interval [CI] = 0.1, 0.9), but were also less likely to report condom use at last vaginal (AOR = 0.6; 95% CI = 0.4, 0.8) and anal sex (AOR = 0.4; 95% CI = 0.3, 0.7). Hispanic US natives were less likely to report condom use at last vaginal sex than were Spanish-speaking immigrants (AOR = 0.6; 95% CI = 0.4, 0.8). English- and Spanish-speaking immigrants did not differ in risky or protective sexual behaviors.Conclusions. Our findings suggest that targeted interventions focusing on unique sexual risks and sociodemographic differences by acculturation level, particularly nativity, may be helpful for preventing sexually transmitted infections.In the United States, Hispanics are one of the subpopulations disproportionately affected by sexually transmitted infections (STIs).1 In 2010, reported cases of chlamydia were 2.7 times higher for Hispanics than for non-Hispanic Whites.1 Similarly, primary and secondary syphilis cases were 2.2 times higher for Hispanics than for non-Hispanic Whites, an increase of 9.5% since 2009.1 Reported gonorrhea rates were also 2.2 times higher for Hispanics than for non-Hispanic Whites. Regarding gender, the racial/ethnic disparity in gonorrhea rates was higher for men (48.7 per 100 000 for Hispanics vs 19.5 per 100 000 for non-Hispanic Whites) than for women (51.1 per 100 000 for Hispanics vs 26.6 per 100 000 for non-Hispanic Whites).1 Among young adult men (18–26 years), STI disparities were even greater; among Hispanic men, the prevalence of chlamydia and gonorrhea was 5.3 and 4.1 times higher than for non-Hispanic White men, respectively.2Research has shown that Hispanics face many unique challenges that increase their risks for STIs, including immigration-related challenges, living apart from their spouse or regular partner, language barriers, racism, social isolation, and limited access to health care.1,3–5 Compared with non-Hispanic Whites, Hispanics often also have higher poverty, unemployment, and high school dropout rates, and are younger.1,4,6 From 2000 to 2010, the Hispanic population in the United States increased by more than 15.2 million (an increase of 43%), contributing to half of the total population growth in the country.7 Because of the growing Hispanic population, the disproportionate burden of STIs, and the numerous barriers and challenges increasing their risk for STIs, an assessment of the sexual behaviors of Hispanics, including risk and protective behaviors, are of public health importance.An epidemiological concept known as the Hispanic paradox posits that health outcomes for Hispanics tend to be more similar to those of non-Hispanic Whites than those of non-Hispanic Blacks because of less acculturation, or “Americanization,” among Hispanics, which has been shown to be associated with lower sexual risk behaviors and better health outcomes.8–10 Some research suggests that the Hispanic paradox is variable and fluid or may not exist at all.11,12 Although many studies have examined the relationship between acculturation and sexual risk behaviors that are related to STI transmission, most of this research has focused on Hispanic women, adolescents, or men who have sex with men.13–22 Fewer studies have examined differences among Hispanic men in their sexual behaviors with female partners in terms of acculturation group. One study found that low-income, recent-immigrant Hispanic men (living in the United States less than 5 years) were more likely to commercially exchange sexual services and less likely to have a main sex partner than established immigrants (living in the United States for more than 5 years).23 Conversely, established Hispanic immigrant men were more likely to report unprotected sexual intercourse and multiple sex partners than recent immigrants.23 For protective behaviors, condom use at last sex did not significantly differ by acculturation among Hispanic men, although condom use is positively associated with acculturation for women.18,24,25 All of these studies were restricted to specific local areas.Acculturation of Hispanics has been measured in many ways—the use of a single variable, a combination of variables, or scales developed to capture the various aspects of acculturation. Complex measures of acculturation include attitudinal and behavioral factors focused on cultural values.10 More intricate scales of acculturation include heritage and mainstream scales with measures of attitude, behavior, and social relations.10,26 However, it is difficult to include comprehensive measures of acculturation in national surveys that have limited space and competing interests. Measures such as language, country of origin, nativity, and length of time in the country are considered proxy measures of acculturation.11,13,19,27–29 The most frequently used variable to measure acculturation is language of interview (English or Spanish) or the language spoken at home.3,13,14,17,19,21,22,24,27–33 Although acculturation is a multifaceted concept, research suggests that language preference may be a reliable proxy for more complex acculturation measures of Hispanics living in the United States.17For an examination of differences in Hispanic men’s sexual behaviors with female partners by level of acculturation, a national-level examination is useful given the diversity of the Hispanic population in the United States, where origin (Mexican, Puerto Rican, Cuban, Central American, etc.) differs by geography.34 Using data from a national survey, we analyzed the recent sexual behaviors of acculturation groups of Hispanic men (categorized by language of interview and nativity) and compared them with those of non-Hispanic White men. Specifically, we sought to examine differences in recent risky and protective sexual behaviors with female partners among acculturation groups using the 2006–2010 National Survey of Family Growth (NSFG).  相似文献   
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Objectives. We sought to understand how local immigration enforcement policies affect the utilization of health services among immigrant Hispanics/Latinos in North Carolina.Methods. In 2012, we analyzed vital records data to determine whether local implementation of section 287(g) of the Immigration and Nationality Act and the Secure Communities program, which authorizes local law enforcement agencies to enforce federal immigration laws, affected the prenatal care utilization of Hispanics/Latinas. We also conducted 6 focus groups and 17 interviews with Hispanic/Latino persons across North Carolina to explore the impact of immigration policies on their utilization of health services.Results. We found no significant differences in utilization of prenatal care before and after implementation of section 287(g), but we did find that, in individual-level analysis, Hispanic/Latina mothers sought prenatal care later and had inadequate care when compared with non-Hispanic/Latina mothers. Participants reported profound mistrust of health services, avoiding health services, and sacrificing their health and the health of their family members.Conclusions. Fear of immigration enforcement policies is generalized across counties. Interventions are needed to increase immigrant Hispanics/Latinos’ understanding of their rights and eligibility to utilize health services. Policy-level initiatives are also needed (e.g., driver’s licenses) to help undocumented persons access and utilize these services.Federal immigration enforcement policies have been increasingly delegated to state and local jurisdictions, leading to increased enforcement activities by local police. This shift has resulted largely from the implementation of 2 federal initiatives: section 287(g) of the Immigration and Nationality Act and the Secure Communities program. Section 287(g) authorizes Immigration and Custom Enforcement to enter into agreements with state and local law enforcement agencies to enforce federal immigration law during their regular, daily law enforcement activities. The original intention was to “target and remove undocumented immigrants convicted of violent crimes, human smuggling, gang/organized crime activity, sexual-related offenses, narcotics smuggling and money laundering.”1 Added to the Immigration and Nationality Act in 1996, section 287(g) was not widely used in its first decade, but its use accelerated in the mid- to late 2000s.2,3The Secure Communities program differs from section 287(g) in that it does not authorize local enforcement bodies to arrest individuals for federal immigration violations. Instead, when individuals are arrested for nonimmigration matters, the Secure Communities program facilitates the sharing of local arrestees’ fingerprints and information with Immigration and Custom Enforcement and the Federal Bureau of Investigation, which checks them against immigration databases. If these checks reveal that an individual is unlawfully present in the United States or otherwise removable because of a criminal conviction, Immigration and Custom Enforcement takes enforcement action.4Some evidence suggests that both section 287(g) and the Secure Communities program contribute to Hispanic/Latino immigrants’ general mistrust of local law enforcement and fear of utilizing a variety of public services, such as police protection and emergency services.2,5–7 Although many immigrant Hispanics/Latinos in the United States experience barriers to care because of a lack of bilingual and bicultural services, low health literacy, insufficient public transportation, and limited knowledge of available health services,8–12 studies have suggested that individuals lacking legal status may have more difficulty obtaining health services and may experience worse health outcomes than do individuals with legal status.13–18 Among immigrant Hispanics/Latinos, the fear of deportation, a lack of required forms of documentation, interaction with law enforcement personnel, and racial profiling are factors also associated with reduced utilization of health services and worse health.6,19–22 Such fears lead to incomplete sequences of care,19,20,23,24 promote the use of nonstandard and unsafe contingencies for care,16,25–27 and contribute to public health hazards, as immigrants delay preventive care or treatment.13,22,28 These fears further affect long-term health outcomes as immigrant Hispanics/Latinos alter their physical activity, food purchasing behaviors, and food consumption because of concerns about being in public.29 They may withhold information from health care providers19 and experience high levels of stress, leading to compromised mental health.20,30,31The Patient Protection and Affordable Care Act bars undocumented or recent legal immigrants from receiving financial assistance for health insurance32; thus, many will continue to remain uninsured and dependent on public health services and free clinics for a significant portion of their care. Because these services are associated with government authority, there is the potential that increasing immigration enforcement policies will deter noncitizens from seeking needed care, not only to their detriment but also to the detriment of public health.Currently there is little research examining the impact of recent immigration enforcement policies on the access to and utilization of health care, and there has been a call to better understand the public health impact of current immigration policies and their enforcement.29 Through mixed methods, we explored the effect of local immigration enforcement policies on access to and utilization of health services among immigrant Hispanics/Latinos in North Carolina. We analyzed vital records data to determine whether there were differences in utilization of prenatal services by Hispanic/Latina mothers pre- and postimplementation of section 287(g), and we conducted focus groups and in-depth interviews with Hispanics/Latinos living in counties that had implemented section 287(g) and in “sanctuary” counties, counties in which leaders, including politicians and clergy, have spoken out against the program.  相似文献   
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The use of an ammonia electrode to quantify ammonia liberated by urease from Helicobacter pylori was assessed in an in vitro study. It was found to be highly sensitive (down to 0.7 ppm NH3) and highly reproducible (coefficient of variation 6.0%). Inhibition of urease by bismuth subsalicylate was evaluated as urease testing is often used to assess clearance of H. pylori in patients treated with bismuth. Concentrations of bismuth subsalicylate up to 5 mg/ml had no inhibitory effect but bismuth subsalicylate at 50 mg/ml resulted in 21% inhibition of the urease activity of an ultrasonicated H. pylori suspension. As a preliminary study, the ammonia electrode was assessed in the endoscopy room in comparison with conventional techniques for H. pylori diagnosis. Antral biopsies from 39 patients attending for routine diagnostic endoscopy were subjected to culture, histology, detection of urease activity with a commercially available slide test (CLO) and with the ammonia electrode to detect ammonia liberated from samples placed in urea solution. 21 patients were positive after 1 h with the ammonia electrode, compared to only 17 with the commercially available slide test. 20 were positive on histology and 19 by culture. All samples positive with the ammonia electrode were either positive by culture or by histology. The ammonia electrode offers a quick, sensitive, quantitative and cheap method for the detection and quantification of H. pylori.  相似文献   
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Catheter closure of secundum atrial septal defect (ASD) using the Amplatzer septal occluder (ASO) is a potential alternative for open surgical repair. However, the large profile of the device obtained immediately after closure continues to raise some concerns regarding its long-term safety. To evaluate the changes in the profile of the device after being deployed, transesophageal echocardiography was performed in 70 patients (17 men and 53 women) who underwent catheter closure of ASDs immediately after and at 6-month follow-up. The median age at closure was 16 years (range 1.9 to 75) and the median size of the ASD as assessed by transesophageal echocardiography was 14 mm (range 3 to 25). The thickness (profile) of the device was assessed in the 4-chamber, short- and long-axis views of the interatrial septum, and measured at its middle and at the junction of the waist with the disc at its 2 ends. Seventy-three devices were deployed in the 70 patients. The median size of the device was 19 mm (range 8 to 34). Complete closure was achieved in 81.4% and 91.4% immediately after and at 6-months follow-up, respectively. The thickness of the device at its middle decreased from 12.2 +/- 4.3, 12.2 +/- 3.7, and 12.5 +/- 4.3 mm in the 4-chamber, short- and long-axis views to 6.5 +/- 2.0, 6.3 +/- 1.9, and 6.5 +/- 2.2 mm, respectively. The thickness of the device at its superior, inferior, anterior, and posterior edges also decreased by 41.8% +/- 14.0% to 43.7% +/- 9.8%. The changes in the thickness were related to device size. Larger devices were thicker after being deployed. We conclude that the thickness of the ASO decreases by 42% to 48% within 6 months after deployment, resulting in a lower profile.  相似文献   
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