Gallstone disease and the risk of stroke: a nationwide population-based study.

BACKGROUND: Gallstone disease (GD) and stroke share a number of risk factors including diabetes and hyperlipidemia. This nationwide population-based study was designed to estimate the risk of stroke after a diagnosis of GD. METHODS: Data were obtained from the Taiwan National Health Insurance Research Database. A total of 135,512 patients with a diagnosis of GD and 271,024 age- and gender-matched non-GD control patients were included to assess the risk of stroke using Cox proportional hazard regression. RESULTS: During the study period (2000-2003), 12,234 (153.67/10,000 person-years) strokes occurred among the GD patients, and 20,680 (114.83/10,000 person-years) among the controls. The diagnosis of GD carried a higher risk of developing ischemic and hemorrhagic stroke, with a hazard ratio (HR) of 1.28 and 1.33 (95% confidence interval [CI], 1.25-1.31 and 1.25-1.41, both P < .0001), respectively. Stroke risk was increased in both genders but at a higher rate in younger age. The GD group had significantly higher prevalence rate of comorbidities that are known stroke risk factors, including hypertension, diabetes, and coronary artery disease. Stroke risk was higher in the GD group with or without any of these comorbidities. CONCLUSIONS: In this population-based longitudinal follow-up study, GD carried a significantly higher stroke risk, particularly for younger age with or without stroke risk factors. Stroke preventive measures maybe needed for patients with GD, especially those of younger age and with stroke risk factor(s).

Association between genetic variant on chromosome 12p13 and stroke survival and recurrence: a one year prospective study in Taiwan.

BACKGROUND: The association between ischemic stroke and 2 single nucleotide polymorphisms (SNPs) on chromosome 12p13, rs12425791 and rs11833579 appears inconsistent across different samples. These SNPs are close to the ninjurin2 gene which may alter the risk of stroke by affecting brain response to ischemic injury. The purpose of this study was to investigate the association between these two SNPs and ischemic stroke risk, as well as prognostic outcomes in a Taiwanese sample. METHODS: We examined the relations of these two SNPs to the odds of new-onset ischemic stroke, ischemic stroke subtypes, and to the one year risk of stroke-related death or recurrent stroke following initial stroke in a case-control study. A total of 765 consecutive patients who had first-ever ischemic stroke were compared to 977 stroke-free, age-matched controls. SNPs were genotyped by Taqman fluorescent allelic discrimination assay. The association between ischemic stroke and SNPs were analyzed by multivariate logistic regression. Cox proportional hazard model was used to assess the effect of individual SNPs on stroke-related mortality or recurrent stroke. RESULTS: There was no significant association between SNP rs12425791 and rs11833579 and ischemic stroke after multiple testing corrections. However, the marginal significant association was observed between SNP rs12425791 and large artery atherosclerosis under recessive model (OR, 2.30; 95%CI, 1.22-4.34; q-value = 0.062). Among the 765 ischemic stroke patients, 59 died or developed a recurrent stroke. After adjustment for age, sex, vascular risk factors and baseline stroke severity, Cox proportional hazard analysis indicated that the hazard ratios were 2.76 (95%CI, 1.34-5.68; q-value, 0.02) and 2.15 (95%CI, 1.15-4.02; q-value, 0.03) for individuals with homozygous variant allele of rs12425791 and rs11833579, respectively. CONCLUSIONS: This is a precedent study that found genetic variants of rs12425791 and rs11833579 on chromosome 12p13 are independent predictors of stroke-related mortality or stroke recurrence in patients with incident ischemic stroke in Taiwan. Further study is needed to explore the details of the physiological function and the molecular mechanisms underlying the association of this genetic locus with ischemic stroke.

Fusobacterium septicemia complicated by cerebral subdural and epidural empyemas: a rare case of Lemierre syndrome.

BACKGROUND: Lemierre syndrome is characterized by postanginal septicemia and internal jugular vein thrombophlebitis with secondary septic emboli, typically to the lungs. The central nervous system (CNS) is rarely involved. OBJECTIVE: To present a case of Lemierre syndrome featuring cerebral subdural and epidural empyemas. CASE REPORT: This case report describes the case of a 17-year-old youth with cerebral subdural and epidural empyemas. The findings of chest computed tomography of the neck and the blood cultures were compatible with Lemierre syndrome. The patient recovered well after antibiotic treatment and surgical debridement. CONCLUSION: Lemierre syndrome can result in infection spreading to the CNS, including cerebral subdural and epidural empyemas. This disease entity should be included in the differential diagnoses of CNS bacterial infections.

Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes.

Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50µg/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50µg/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50µg/l).

EtcABC, a Putative EII Complex, Regulates Type 3 Fimbriae via CRP-cAMP Signaling in Klebsiella pneumoniae.

Biofilm formation by Klebsiella pneumoniae on indwelling medical devices increases the risk of infection. Both type 1 and type 3 fimbriae are important factors in biofilm formation by K. pneumoniae. We found that a putative enzyme II (EII) complex of the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS), etcA (EIIA)-etcB (EIIB)-etcC (EIIC), regulated biofilm and type 3 fimbriae formation by K. pneumoniae STU1. In this study, the regulatory mechanism of etcABC in K. pneumoniae type 3 fimbriae formation was investigated. We found via quantitative RT-PCR that overexpression of etcABC enhanced the transcription level of the mrk operon, which is involved in type 3 fimbriae synthesis, and reduced the transcription level of the fim operon, which is involved in type 1 fimbriae synthesis. To gain further insight into the role of etcABC in type 3 fimbriae synthesis, we analyzed the region upstream of the mrk operon and found the potential cyclic 3'5'-adenosine monophosphate (cAMP) receptor protein (CRP) binding site. After crp was deleted in K. pneumoniae STU1 and two clinical isolates, these three crp mutant strains could not express MrkA, the major subunit of the fimbrial shaft, indicating that CRP positively regulated type 3 fimbriae synthesis. Moreover, a crp mutant overexpressing etcABC could not express MrkA, indicating that the regulation of type 3 fimbriae by etcABC was dependent on CRP. In addition, deletion of cyaA, which encodes the adenylyl cyclase that synthesizes cAMP, and deletion of crr, which encodes the glucose-specific EIIA, led to a reduction in lac operon regulation and therefore bacterial lactose uptake in K. pneumoniae. Exogenous cAMP but not etcABC overexpression compensated for the role of cyaA in bacterial lactose uptake. However, either etcABC overexpression or exogenous cAMP compensated for the role of crr in bacterial lac operon regulation that would eventually restore lactose uptake. We also found via ELISA and the luxCDABE reporter system that overexpression of etcABC increased intracellular cAMP levels and the transcription level of crp, respectively, in K. pneumoniae. In conclusion, overexpression of etcABC positively regulated cAMP production and cAMP-CRP activity to activate the mrk operon, resulting in increased type 3 fimbriae synthesis in K. pneumoniae.

Phosphoenolpyruvate phosphotransferase system components positively regulate Klebsiella biofilm formation.

BACKGROUND/PURPOSE: Klebsiella pneumoniae is one of the leading causes of device-related infections (DRIs), which are associated with attachment of bacteria to these devices to form a biofilm. The latter is composed of not only bacteria but also extracellular polymeric substances (EPSes) consisting of extracellular DNAs, polysaccharides, and other macromolecules. The phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) regulates diverse processes of bacterial physiology. In the genome of K. pneumoniae MGH 78578, we found an uncharacterized enzyme II complex homolog of PTS: KPN00353 (EIIA homolog), KPN00352 (EIIB homolog), and KPN00351 (EIIC homolog). The aim of this study was to characterize the potential physiological role of KPN00353, KPN00352, and KPN00351 in biofilm formation by K. pneumoniae. METHODS/RESULTS: We constructed the PTS mutants and recombinant strains carrying the gene(s) of PTS. The recombinant K. pneumoniae strain overexpressing KPN00353-KPN00352-KPN00351 produced more extracellular matrix than did the vector control according to transmission and scanning electron microscopy. Judging by quantification of biofilm formation, of extracellular DNA (eDNA), and of capsular polysaccharide, the recombinant strain overexpressing KPN00353-KPN00352-KPN00351 produced more biofilm and capsular polysaccharide after overnight culture and more eDNA in the log phase as compared to the vector control. CONCLUSION: The genes, KPN00353-KPN00352-KPN00351, encode a putative enzyme II complex in PTS and positively regulate biofilm formation by enhancing production of eDNA and capsular polysaccharide in K. pneumoniae. Five proteins related to chaperones, to the citric acid cycle, and to quorum sensing are upregulated by the KPN00353-KPN00352-KPN00351 system.

The Negative Effects of KPN00353 on Glycerol Kinase and Microaerobic 1,3-Propanediol Production in Klebsiella pneumoniae.

1,3-Propanediol (1,3-PD) is a valuable chemical intermediate in the synthesis of polyesters, polyethers, and polyurethanes, which have applications in various products such as cloth, bottles, films, tarpaulins, canoes, foam seals, high-resilience foam seating, and surface coatings. Klebsiella pneumoniae can produce 1,3-PD from glycerol. In this study, KPN00353, an EIIA homologue in the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS), was found to play a negative regulatory role in 1,3-PD production under microaerobic conditions via binding to glycerol kinase (GlpK). The primary sequence of KPN00353 is similar to those of the fructose-mannitol EIIA (EIIFru and EIIAMtl) family. The interaction between KPN00353 and GlpK resulted in inhibition of the synthesis of glycerol-3-phosphate (G3P) and correlated with reductions in glycerol uptake and the production of 1,3-PD. Based on structure modeling, we conclude that residue H65 of KPN00353 plays an important role in the interaction with GlpK. We mutated this histidine residue to aspartate, glutamate, arginine and glutamine to assess the effects of each KPN00353 variant on the interaction with GlpK, on the synthesis of G3P and on the production of 1,3-PD. Our results illuminate the role of KPN00353 in 1,3-PD production by K. pneumoniae under microaerobic conditions.

Elevated levels of soluble adhesion molecules in sera of patients with acute bronchiolitis.

The mechanisms of migration of neutrophils into the airway lumen are crucial in the development of airway injury of acute bronchiolitis and are mediated by adhesion molecules. In this study, we have attempted to evaluate the role of serum concentrations of the soluble form of intercellular adhesion molecule-1 (sICAM-1) in the disease activity in acute bronchiolitis and in respiratory syncytial virus (RSV) infection. Circulating levels of sICAM-1 in sera from 10 normal control subjects, and from 47 hospitalized acute bronchiolitis patients at admission, and from 25 patients on the day of discharge were determined by use of commercially available enzyme-linked immunosorbent assay kits. The mean serum level of sICAM-1 in bronchiolitis patients was significantly higher than in the 10 healthy control infants (345.8 +/- 99.7 microg/mL vs 237.1 +/- 81.7 microg/mL; p<0.05). However, the mean sICAM-1 concentration was similar between RSV-positive and RSV-negative patients (337.5 +/- 99.6 microg/mL vs 350.9 +/- 101.1 microg/mL; p=0.65). Although the mean clinical severity score of RSV-positive patients was significantly higher than that of RSV-negative patients (5.94 +/- 1.83 vs 3.48 +/- 1.70; p<0.05). The improvement of clinical severity score was not well correlated with the change of sICAM-1 level (r=0.22). This study provides evidence that serum levels of sICAM-1 are increased in acute bronchiolitis and further confirms the role of adhesion molecules involved in the pathogenesis of the disease. However, the serum concentrations of the soluble adhesion molecules could not reliably reflect the clinical severity of the disease.

Clinical aspects of X-linked hypophosphatemic rickets.

X-link hypophosphatemia (XLH) is the most common heritable form of rickets and is usually transmitted as an X-linked dominant disorder Until now there is no report about clinical data of XLH in Taiwan. We retrospectively studied 15 patients (5 males and 10 females) of XLH in our hospital in the past 18 years to delineate the clinical aspects of this disease. A total of 7 patients had family histories consistent with XLH; 8 appeared to be sporadic cases. Fourteen of 15 cases had typical physical and radiologic findings of rickets except case 1 who only had waddling gait and sacroiliitis with the initial complaint of joint pain. All 15 cases had normal serum creatinine, normocalcemia, normal 1,25-dihydroxyvitamin D (1,25-(OH)2D), reduced serum phosphate concentration, reduced urinary calcium excretion and reduced TmP/GFR. All but one had reduced %TRP. Thirteen of 15 cases had elevated alkaline phosphatase activity; two showed hyperparathyroidism. Four cases had sufficient follow-up growth data and had an increase in height percentile and velocity after combination therapy.

Increased risk of stroke after septicaemia: a population-based longitudinal study in Taiwan.

Inflammation and infection have been noted to increase stroke risk. However, the association between septicaemia and increased risk of stroke remains unclear. This population-based cohort study, using a National Health Insurance database, aimed to investigate whether patients with septicaemia are predisposed to increased stroke risk. The study included all patients hospitalised for septicaemia for the first time between 2000 and 2003 without prior stroke. Patients were followed until the end of 2010 to evaluate incidence of stroke. An age-, gender- and co-morbidities-matched cohort without prior stroke served as the control. Cox's proportional hazards regressions were used to assess differences in stroke risk between groups. Based on hazard ratios (HRs), patients with septicaemia had greater stroke risk, especially in the younger age groups (age <45: HR = 4.16, 95% CI: 2.39-7.24, p<0.001; age 45-64: HR = 1.76, 95% CI: 1.41-2.19, p<0.001; age ≥ 65: HR = 1.05, 95% CI: 0.91-1.22, p>0.05). Haemorrhagic stroke was the dominant type (ischaemic stroke: HR = 1.20, 95% CI: 1.06-1.37, p<0.01; haemorrhagic stroke: HR = 1.82, 95% CI: 1.35-2.46, p<0.001) and patients without co-morbidities were at slightly higher risk (without co-morbidities: HR = 1.49, 95% CI: 1.02-2.17, p<0.05; with co-morbidities: HR = 1.24, 95% CI: 1.10-1.41, p<0.001). The impact of septicaemia on stroke risk was highest within 6 months of the event and gradually declined over time. Our results suggest that septicaemia is associated with an increase in stroke risk, which is greatest in haemorrhagic stroke. Closer attention to patients with history of septicaemia may be warranted for stroke preventive measures, especially for younger patients without co-morbidities.