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31.
Background: Streptococcus gallolyticus subsp. gallolyticus bacteremia is associated with colorectal malignancies. There is limited data regarding the association of Streptococcus gallolyticus subsp. pasteurianus with malignancies. We aimed to study the pattern of isolation of Streptococcus gallolyticus and analysis of risk factors in patients with hepatobiliary diseases. We also planned to evaluate its association with hepatocellular malignancy.

Methods: We analyzed clinical and laboratory data of 68 cases of Streptococcus gallolyticus infections (77 isolates) from January 2013 to December 2017. These included blood (58), ascitic fluid (15), bile (2) and pleural fluid (2). We analyzed the risk factors in patients developing malignancy with Streptococcus gallolyticus infections.

Results: Amongst the 68 patients studied, eight (11.76%) had confirmed malignancies, hepatocellular carcinoma (HCC) (5), rectal adenocarcinoma (1), pancreatic carcinoma (1) and uterine tumors (1). Simultaneous isolation of S. gallolyticus subsp. pasteurianus from blood and ascitic fluid in eight patients (11.8%, p = .01) was significantly associated with the occurrence of HCC. Streptococcus gallolyticus infection with HCC was associated with younger age (median 55 years), lymphocytosis and elevated gamma-glutamyl transferase (GGT).

Conclusions: This study provides a novel insight into the association of Streptococcus gallolyticus subspecies pasteurianus with HCC. The isolation of the organism from blood and ascitic fluid should prompt the clinicians to search for evidence of HCC actively.  相似文献   
32.
Streptococcus dysgalactiae subsp. equisimilis (groups C and G streptococci [GCS/GGS]) is an increasingly recognized human pathogen, although it may follow indirect pathways. Prospective surveillance of selected households in 3 remote Aboriginal communities in Australia provided 337 GCS/GGS isolates that were emm sequence-typed. Lancefield group C isolates (GCS) were localized to specific households and group G isolates (GGS) were more evenly distributed. GCS/GGS was more frequently recovered from the throat than group A streptococci (GAS [S. pyogenes]) but rarely recovered from skin sores, and then only with Staphylococcus aureus or GAS. Symptomatic GGS/GGC pharyngitis was also rare. Specific emm sequence types of GCS/GGS did not appear to cycle through the communities (sequential strain replacement) in a manner suggesting acquisition of type-specific immunity. These communities already have high levels of streptococcal and poststreptococcal disease. GCS/GGS may increase in importance as it acquires key virulence factors from GAS by lateral gene transfer.  相似文献   
33.
Paratuberculosis (PTB) or Johne’s disease is a common ruminant infectious disease caused by Mycobacterium avium subsp. paratuberculosis (MAP). In this study, two MAP antigens were compared for their diagnostic utility to detect subclinical PTB in a sheep flock in Mexicali, Mexico. Sheep (n = 31) without clinical signs but positive on a direct fecal-polymerase chain reaction were tested with two preabsorbed in-house enzyme linked immunosorbent assays (ELISAs) using: (1) an ethanol-extracted surface lipid antigen (EVELISA) and (2) a protoplasmic antigen (ELISA-PPA). Sensitivities of the EVELISA and ELISA-PPA were 84% (95% CI; 66–95%) and 29% (95% CI; 14–48%), respectively. The EVELISA test could be a fast and effective way to identify subclinical ovine PTB for severely affected flocks.  相似文献   
34.
Objective: To describe two cases of endocarditis caused by Neisseria elongata subsp. nitroreducens, and present some biochemical characteristics not previously described as useful for differentiating this taxon from Kingella denitrificans .
Methods: Biochemical and antimicrobial susceptibility tests were carried out on four field strains and three reference strains of N. elongata subsp. nitroreducens, the type strains of N. elongata subsp. elongata and N. elongata subsp. glycolytica, and five reference strains of K. denitrificans .
Results: Phenotypic characterization confirmed the identification of N. elongata subsp. nitroreducens in two cases of endocarditis in patients with pre-existing heart damage. Apart from the previously reported differential characteristics between N. elongata subsp. nitroreducens and K. denitrificans, N. elongata subsp. nitroreducens was found to have large mucoid colonies, a positive result of the phenylalanine test, acid production from ethanol and susceptibility to polymyxin, in contrast to K. denitrificans .
Conclusion: When blood cultures are positive for N. elongata subsp. nitroreducens, endocarditis should be suspected. Characteristics useful for differentiating N. elongata subsp. nitroreducens from K. denitrificans are larger colonies, reduction of nitrate and nitrite without gas formation, a positive result of the phenylalanine test, production of acid from ethanol and polymyxin susceptibility.  相似文献   
35.
Summary During a six-year period five patients withCampylobacter fetus subspecies fetus infections were seen at the Mayo Clinic in Rochester, Minnesota. Bacteremia was observed in two patients, one presenting with aortic valve endocarditis and the other with abdominal atherosclerotic aortic aneurysm.C. fetus subsp. fetus was isolated from tibial tissue of a patient with osteomyelitis. Diarrhea was the main complaint of two further patients, and was also mentioned by the patient with the aortic aneurysm. Despite the use of incubation conditions and selective media geared to detect onlyCampylobacter jejuni, C. fetus subsp. fetus was isolated from stool specimens of the two patients with gastrointestinal symptoms. The fact that three of fiveC. fetus subsp. fetus infections observed in this study were associated with intestinal symptoms further supports the importance of the gastrointestinal tract in the pathogenesis ofC. fetus subsp. fetus infections.  相似文献   
36.
Two new triterpeniods, 1ß, 2a, 3ß, 19a-tetrahydroxyurs-12-ene-28-oate and 1ß, 2ß, 3ß, 19-a-tetrahydroxyurs-12-ene-28-oate, have been isolated from the whole plant of Centipeda minima and their structure elucidated on the basis of chemical and spectral evidence.  相似文献   
37.
The historic suggestion that Mycobacterium avium subsp. paratuberculosis (Map) might be a zoonotic pathogen was based on the apparent similarity of lesions in the intestine of patients with Crohn’s disease (CD) with those present in cattle infected with Map, the etiological agent of Johne’s disease. Reluctance to fully explore this possibility has been attributed to the difficulty in demonstrating the presence of Map in tissues from patients with CD. Advances in technology have resolved this problem and revealed the presence of Map in a significant proportion of patients with CD and other diseases. The seminal finding from recent investigations, however, is the detection of Map in healthy individuals with no clinical signs of disease. The latter observation indicates all humans are susceptible to infection with Map and lends support to the thesis that Map is zoonotic, with a latent stage of infection similar to tuberculosis, where infection leads to the development of an immune response that controls but does not eliminate the pathogen. This clarifies one of the reasons why it has been so difficult to document that Map is zoonotic and associated with the pathogenesis of CD and other diseases. As discussed in the present review, a better understanding of the immune response to Map is needed to determine how infection is usually kept under immune control during the latent stage of infection and elucidate the triggering events that lead to disease progression in the natural host and pathogenesis of CD and immune related diseases in humans.  相似文献   
38.
Bifidobacterium animalis subsp. lactis HN019 (HN019) ameliorates chronic idiopathic constipation. Our aim was to determine the efficacy and safety of 28-day supplementation with 1 × 109 or 1 × 1010 CFU of HN019/day for constipation. A total of 228 adults who were diagnosed with functional constipation according to the Rome III criteria were randomized in a double-blind and placebo-controlled trial. Colonic transit time (CTT), the primary outcome, and secondary outcomes that were measured using inventories—patient assessment of constipation symptoms (PAC-SYM) and quality of life (PAC-QoL), bowel function index (BFI), bowel movement frequency (BMF), stool consistency, degree of straining, bowel emptying, bloating, and pain severity—were assessed. Ancillary parameters and harms were also evaluated.

There were no statistically significant differences in the primary or secondary outcomes between interventions. A post hoc analysis of 65 participants with fewer than 3 bowel movements per week (BMF ≤ 3/week) showed a physiologically relevant increase in weekly BMF in the high- (+2.0) and low-dose (+1.7) HN019 groups—by RMANOVA, the HN019 groups with BMF ≤ 3/week, pooled together, had a higher BMF versus placebo (P value = 0.01). Thus, improving low stool frequency could be a target of future interventions with HN019. High-dose HN019 also decreased the degree of straining at Day 28 versus placebo in those with BMF ≤ 3/week (P value = 0.02). Three unlikely related AEs—2 with low-dose HN019 and 1 with placebo—were followed until full recovery. In conclusion, although there were no differences in the primary analysis, HN019 is well tolerated and improves BMF in adults with low stool frequency.  相似文献   

39.
Streptococcus equi subsp. zooepidemicus infections are infrequent in humans. A clinical and epidemiological study of a milk-borne outbreak caused by this organism is described. Fifteen patients (5 females, 10 males) with a median age of 70 years (range 47–86) were infected. Twelve (80%) had underlying diseases. Infection with S. equi subsp. zooepidemicus presented as primary bacteremia in six cases, as bacteremia associated with aortic aneurism in four cases, as septic arthritis in two cases, as pneumonia in two cases, and as meningitis in one case. Five (33.3%) patients died. A case-control study proved that consumption of inadequately pasteurized cheese of a specific brand was associated with S. equi subsp. zooepidemicus disease (OR=4.5; 95% CI 1.57–19.27; p<0.001). This outbreak serves as a reminder that S. equi subsp. zooepidemicus causes serious infections that are usually zoonoses. Identification of beta-hemolytic streptococci to the species level to detect contaminated foods of animal origin is important for preventing new food-borne outbreaks. For a precise characterization of the isolates, the application of molecular markers is recommended.  相似文献   
40.
红火麻化学成分的分离与鉴定   总被引:1,自引:0,他引:1  
目的研究蝎子草属植物红火麻的化学成分。方法利用各种色谱法进行分离纯化,通过理化性质和波谱数据分析进行结构鉴定。结果从红火麻中分离并鉴定了10个化合物,分别为金色酰胺醇乙酸酯(aurantiamide acetate,1)、齐墩果酸(oleanolic acid,2)、2α,3α,19α-三羟基-12-烯-28-乌苏酸(2α,3α,19α-trihydroxyurs-12-en-28-oic,3)、东莨菪素(scopoletin,4)、3-甲氧基-4-羟基苯甲酸(3-methoxy-4-hydroxybenzoic acid,5)、对羟基苯甲酸(p-hydroxybenzoic acid,6)、β-谷甾醇(β-si-tosterol,7)、胡萝卜苷(daucosterol,8)、5-羟甲基糠醛(5-hydroxymethyl furaldehyde,9)、甘露糖(mannose,10)。结论化合物1~10均为首次从红火麻中分离得到,化合物1~6、8~10为首次从蝎子草属植物中分离得到。  相似文献   
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