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151.
152.

Background

Early identification of persons with undiagnosed HIV infection is an important health care issue. We examined associations between diseases diagnosed in hospitals and risk of subsequent HIV diagnosis.

Methods

In this population-based case control study, cases were persons with incident HIV infection diagnosed in Denmark between 1 January 1995 and 1 June 2008. Risk-set sampling was used to identify 19 age- and gender-matched population controls for each HIV case, using the HIV diagnosis date as the index date for both cases and controls. Prior hospital diagnoses obtained from Danish medical databases were first categorized into 22 major disease categories (excluding AIDS-defining diseases except tuberculosis) and then subdivided into 161 subcategories, allowing us to examine specific diseases as potential HIV indicators by conditional logistic regression.

Results

The study included 2,036 HIV cases and 35,718 controls. Persons with the following disease categories had a high risk of HIV diagnosis during the subsequent 5-year period: sexually transmitted infections and viral hepatitis (adjusted odds ratio [aOR] = 12.3, 95% CI: 9.60–15.7), hematological diseases (aOR = 4.28, 3.13–5.85), lower respiratory tract infections (aOR = 3.98, 3.14–5.04)), CNS infections (aOR = 3.44, 1.74–6.80), skin infections (aOR = 3.05, 2.47–3.75), other infections (aOR = 4.64, 3.89–5.54), and substance abuse (aOR = 2.60, 2.06–3.29). Several specific diseases were associated with aORs >20 including syphilis, hepatitis A, non “A” viral hepatitis, herpes zoster, candida infection, endocarditis, thrombocytopenia, and opioid abuse.

Conclusions

Targeted testing for HIV in patients diagnosed with diseases associated with HIV may lead to earlier treatment and thereby reduced morbidity, mortality and HIV transmission.  相似文献   
153.
  总被引:7,自引:0,他引:7  
  相似文献   
154.
    
Coagulation factor VIIa (FVIIa) requires tissue factor (TF) to attain full catalytic competency and to initiate blood coagulation. In this study, the mechanism by which TF allosterically activates FVIIa is investigated by a structural dynamics approach that combines molecular dynamics (MD) simulations and hydrogen/deuterium exchange (HX) mass spectrometry on free and TF-bound FVIIa. The differences in conformational dynamics from MD simulations are shown to be confined to regions of FVIIa observed to undergo structural stabilization as judged by HX experiments, especially implicating activation loop 3 (residues 365-374{216-225}) of the so-called activation domain and the 170-loop (residues 313-322{170A-175}) succeeding the TF-binding helix. The latter finding is corroborated by experiments demonstrating rapid deglycosylation of Asn322 in free FVIIa by PNGase F but almost complete protection in the presence of TF or an active-site inhibitor. Based on MD simulations, a key switch of the TF-induced structural changes is identified as the interacting pair Leu305{163} and Phe374{225} in FVIIa, whose mutual conformations are guided by the presence of TF and observed to be closely linked to the structural stability of activation loop 3. Altogether, our findings strongly support an allosteric activation mechanism initiated by the stabilization of the Leu305{163}/Phe374{225} pair, which, in turn, stabilizes activation loop 3 and the S(1) and S(3) substrate pockets, the activation pocket, and N-terminal insertion.  相似文献   
155.
156.
Seasonal measurements of the oxygen and nitrate uptake by a reed swamp sediment were carried out in a shallow, eutrophic Danish lake, Arreskov Sø. The oxidation of organic carbon in the sediment by aerobic and nitrate respiration was 290 and 188 g C m−2 yr−1 respectively. During winter, nitrate respiration amounted to 94% of the total carbon oxidation, whereas it was zero during summer. On an annual basis nitrate respiration constituted 39% of total respiration. Sediment nitrate uptake was correlated to nitrate concentration. In consequence of this the nitrate uptake rates varied during the year from zero in summer to 55 mg N m−2 d−1 in spring.
Oxygen uptake rates varied from 30 to 250 mg O2 m−2 h−1 during the year, with a maximum uptake in August. The oxygen uptake per year was calculated to 860 g O2 m−2. The oxygen uptake rate was correlated to lake temperature and Kjeldahl nitrogen content of the sediment. The oxygen uptake rate, however, showed no correlation with loss on ignition of the sediment. A Q10-value of 2.2 was found for lake measurements in the temperature interval of 5–15°C. The corresponding O10-value in the laboratory was 2.6. A high microbial biomass indicated by the maximum content of Kjeldahl nitrogen and the lowest ratio of loss on ignition on Kjeldahl nitrogen appeared in late August, when the maximum oxygen uptake occurred. The oxygen uptake rate increased during the time interval from sampling to the start of the experiments.  相似文献   
157.
BackgroundCycling is a recreational activity and mode of commuting with substantial potential to improve public health in many countries around the world. The aim of this study was to examine prospective associations between recreational and commuter cycling, changes in cycling habits, and risk of type 2 diabetes (T2D) in Danish adults from the Diet, Cancer and Health cohort study.ConclusionsCommuter and recreational cycling was consistently associated with lower risk of T2D in Danish adults. Our results also provide evidence that late-in-life initiation of or continued engagement in cycling lowers risk of T2D.  相似文献   
158.

Introduction

The purpose of the study was to describe demographic and clinical characteristics and outbreak handling of a large methicillin-resistant Staphylococcus aureus (MRSA) outbreak in a neonatal intensive care unit (NICU) in Denmark June 25th–August 8th 2008, and to identify risk factors for MRSA transmission.

Methods

Data were collected retrospectively from medical records and the Danish Neobase database. All MRSA isolates obtained from neonates, relatives and NICU health care workers (HCW) as well as environmental cultures were typed.

Results

During the 46 day outbreak period, 102 neonates were admitted to the two neonatal wards. Ninety-nine neonates were subsequently sampled, and 32 neonates (32%) from 25 families were colonized with MRSA (spa-type t127, SCCmec V, PVL negative). Thirteen family members from 11 of those families (44%) and two of 161 HCWs (1%) were colonized with the same MRSA. No one was infected. Five environmental cultures were MRSA positive. In a multiple logistic regression analysis, nasal Continuous Positive Airway Pressure (nCPAP) treatment (p = 0.006) and Caesarean section (p = 0.016) were independent risk factors for MRSA acquisition, whereas days of exposure to MRSA was a risk factors in the unadjusted analysis (p = 0.04).

Conclusions

MRSA transmission occurs with high frequency in the NICU during hospitalization with unidentified MRSA neonates. Caesarean section and nCPAP treatment were identified as risk factors for MRSA colonization. The MRSA outbreak was controlled through infection control procedures.  相似文献   
159.

Background and Objectives

Infections are common complications among patients on chronic hemodialysis. This population-based cohort study aims to estimate risk and case fatality of bloodstream infection among chronic hemodialysis patients.

Methods

In this population-based cohort study we identified residents with end-stage renal disease in Central and North Jutland, Denmark who had hemodialysis as first renal replacement therapy (hemodialysis patients) during 1995–2010. For each hemodialysis patient, we sampled 19 persons from the general population matched on age, gender, and municipality. Information on positive blood cultures was obtained from regional microbiology databases. All persons were observed from cohort entry until first episode of bloodstream infection, emigration, death, or end of hemodialysis treatment, whichever came first. Incidence-rates and incidence-rate ratios were computed and risk factors for bloodstream infection assessed by Poisson regression. Case fatality was compared by Cox regression.

Results

Among 1792 hemodialysis patients and 33 618 matched population controls, we identified 461 and 1126 first episodes of bloodstream infection, respectively. Incidence rates of first episode of bloodstream infection were 13.7 (95% confidence interval (CI), 12.5–15.0) per 100 person-years among hemodialysis patients and 0.53 (95% CI, 0.50–0.56) per 100 person-years among population controls. In hemodialysis patients, the most common causative microorganisms were Staphylococcus aureus (43.8%) and Escherichia coli (12.6%). The 30-day case fatality was similar among hemodialysis patients and population controls 16% (95% CI, 13%–20%) vs. 18% (95% CI, 15%–20%).

Conclusions

Hemodialysis patients have extraordinary high risk of bloodstream infection while short-term case fatality following is similar to that of population controls.  相似文献   
160.
  总被引:1,自引:0,他引:1  
In Arabidopsis thaliana , the class I hemoglobin AHb1 is transiently expressed in the hydathodes of leaves and in floral buds from young inflorescences. Nitric oxide (NO) accumulates to high levels in these organs when AHb1 is silenced, indicating an important role in metabolizing NO. AHb1 -silenced lines are viable but show a mutant phenotype affecting the regions where AHb1 is expressed. Arabidopsis lines with an insertional knockout or overexpression of AHb2, a class II 3-on-3 hemoglobin, were generated. Seedlings overexpressing AHb2 show enhanced survival of hypoxic stress. The AHb2 knockout lines develop normally. However, when AHb2 knockout is combined with AHb1 silencing, seedlings die at an early vegetative stage suggesting that the two 3-on-3 hemoglobins, AHb1 and AHb2, together play an essential role for normal development of Arabidopsis seedlings. In conclusion, these results suggests that 3-on-3 hemoglobins apart from a role in hypoxic stress play a general role under non-stressed conditions where they are essential for normal development by controlling the level of NO which tends to accumulate in floral buds and leaf hydathodes of plants.  相似文献   
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