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71.
Blood counts, hemoglobin (Hb) high performance liquid chromatography (HPLC), and DNA analyses were performed on 260 children, aged 5 months to 16 years, at Siem Reap to assess the prevalence of thalassemia and other hemoglobinopathies in regional Cambodia. Hemoglobinopathies were present in 134 children (51.5%) with 20 abnormal genotypes identified. alpha-Thalassemia (thal) (35.4%) was the most prevalent disorder and the -alpha3.7 gene deletion was the most common alpha-globin gene abnormality. The - -SEA deletion and nondeletional forms of alpha-thal, Hb Constant Spring [Hb CS, alpha142, Term-->Gln, TAA-->CAA (alpha2)], Hb Paksé [alpha142, Term-->Tyr, TAA-->TAT (alpha2)] and triplicated alpha genes, were also present but at low frequencies. Hb E [beta26(B8)Glu-->Lys, GAG-->AAG] (28.8%) was the most common beta-globin gene abnormality, whilst beta-thal was only detected in two children (0.8% of cases). Although hemoglobinopathies were common, the majority of abnormalities detected (heterozygous -alpha3.7 and Hb E) were not clinically significant. On the basis of these findings, and with the majority of abnormalities being mild, it seems improbable that thalassemia represents a major health burden in this region of Cambodia.  相似文献   
72.
Many patients with obstructive sleep apnea (OSA), but not all, have a reduction in blood pressure (BP) with positive airway pressure (PAP) treatment. Our objective was to determine whether the BP response following PAP treatment is related to obesity. A total of 188 adults with OSA underwent 24‐hour BP monitoring and 24‐hour urinary norepinephrine collection at baseline. Obesity was assessed by waist circumference, body mass index, and abdominal visceral fat volume. Participants adherent to PAP treatment were reassessed after 4 months. Primary outcomes were 24‐hour mean arterial pressure (MAP) and 24‐hour urinary norepinephrine level. Obstructive sleep apnea participants had a significant reduction in 24‐hour MAP following PAP treatment (−1.22 [95% CI: −2.38, −0.06] mm Hg; P = .039). No significant correlations were present with any of the 3 obesity measures for BP or urinary norepinephrine measures at baseline in all OSA participants or for changes in BP measures in participants adherent to PAP treatment. Changes in BP measures following treatment were not correlated with baseline or change in urinary norepinephrine. Similar results were obtained when BP or urinary norepinephrine measures were compared between participants dichotomized using the sex‐specific median of each obesity measure. Greater reductions in urinary norepinephrine were correlated with higher waist circumference (rho = −0.21, P = .037), with a greater decrease from baseline in obese compared to non‐obese participants (−6.26 [−8.82, −3.69] vs −2.14 [−4.63, 0.35] ng/mg creatinine; P = .027). The results indicate that the BP response to PAP treatment in adults with OSA is not related to obesity or urinary norepinephrine levels.  相似文献   
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The global emergence of zoonotic viruses, including poxviruses, poses one of the greatest threats to human and animal health. Forty years after the eradication of smallpox, emerging zoonotic orthopoxviruses, such as monkeypox, cowpox, and vaccinia viruses continue to infect humans as well as wild and domestic animals. Currently, the geographical distribution of poxviruses in a broad range of hosts worldwide raises concerns regarding the possibility of outbreaks or viral dissemination to new geographical regions. Here, we review the global host ranges and current epidemiological understanding of zoonotic orthopoxviruses while focusing on orthopoxviruses with epidemic potential, including monkeypox, cowpox, and vaccinia viruses.  相似文献   
76.

Purpose

Low-dose multislice-CT (MSCT) detects many early-stage lung cancers with good prognosis, but whether it decreases lung cancer mortality and at which costs is yet insufficiently explored. Scope of the present study is to examine within a common European effort whether MSCT screening is capable to reduce the lung cancer mortality by at least 20?% and at which amount of undesired side effects this could be achieved.

Methods

Overall 4,052 heavy smoking men and women were recruited by a population-based approach and randomized into a screening arm with five annual MSCT screens and an initial quit-smoking counseling, and a control arm with initial quit-smoking counseling and five annual questionnaire inquiries.

Results

In the first screening round, 2,029 participants received a MSCT providing 1,488 negative and 540 suspicious screens with early recalls (early recall rate 26.6?%) leading to 31 biopsies (biopsy rate 1.5?%) and 22 confirmed lung cancers (detection rate 1.1?%). Among the lung cancers, 15 were adenocarcinomas, 3 squamous cell carcinomas, one small-cell lung cancer, and 3 others, whereby 18 were in clinical stage I, one in stage II, and 3 in stage III. One interval cancer occurred.

Conclusions

The indicated performance indicators fit into the range observed in comparable trials. The study continues finalizing the second screening round and for the first participants even the last screening round. The unresolved issue of the precise amount of side effects and the high early recall rate precludes currently the recommendation of MSCT as screening tool for lung cancer.  相似文献   
77.
In a cohort of patients receiving care for HIV, we examined longitudinally the impact of past 30-day frequency of heavy drinking (consuming 5+ drinks on one occasion) on HIV-related (detectable viral load and CD4+ T cell count) and non-HIV-related (hemoglobin and biomarkers of kidney function and liver fibrosis) clinical outcomes and the extent to which these effects were due to reduced antiretroviral therapy (ART) adherence. Data came from the Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy. Between March 2004 and June 2006, 533 individuals receiving ART were recruited and followed every 6 months for six years. Using longitudinal mediation analysis, we estimated natural direct effects (NDE) of heavy drinking frequency (never, 1–3 times, or 4+ times in the past 30 days) on clinical outcomes and natural indirect effects (NIE) mediated via ART adherence. A one-level increase in heavy drinking frequency had a significant negative NDE on CD4+ T-cell counts (-10.61 cells/mm3; 95 % CI [-17.10, -4.12]) and a significant NIE through reduced ART adherence of -0.72 cells/mm3 (95 % CI [-1.28, -0.15]), as well as a significant NIE on risk of detectable viral load (risk ratio = 1.03; 95 % CI [1.00, 1.05]). Heavy drinking had a significant detrimental NIE on a combined index of 5-year mortality risk and detrimental NDE and total effect on a biomarker of liver fibrosis. Heavy drinking has deleterious effects on multiple clinical outcomes in people living with HIV, some of which are mediated through reduced ART adherence.  相似文献   
78.
Halothane has been shown to be a powerful myocardial protectant during normothermic cardioplegic arrest and subsequent reperfusion. In view of its multiple effects on cellular Ca2+ movements and the role of this ion in ischemia-reperfusion injury, the questions of whether halothane is capable of maximally protecting the heart or whether combination therapy of halothane with other Ca2+ blocking agents may be more effective arose. Therefore, the effects of combination therapy with halothane and a calcium antagonist (nifedipine), or a Na+/H+ inhibitor (HOE 694), or a Na+/Ca2+ inhibitor (quinacrine) on postcardioplegic functional recovery were evaluated. The isolated perfused rat heart subjected to 45 minutes normothermic cardiac arrest was used as an experimental model. Dose–response curves were performed for each drug. Using the optimal dosage for each drug, the following results were obtained: (1) Nifedipine (10–7 M; administered retrogradely 10 minutes before and after cardioplegia) and halothane (1.5% administered during cardioplegia), when administered separately, improved functional recovery. Combination therapy did not further improve protection. (2) HOE 694 (10–7 M) or quinacrine (10–9 M) improved postcardioplegic functional recovery when added for 2 minutes at the onset of reperfusion. Simultaneous administration of HOE 694 and 1.5% halothane was the only combination that yielded additive protection. (3) Quinacrine, a phospholipase and Na+/Ca2+ exchanger inhibitor, appeared to be the most powerful drug used. In summary, the results obained indicate that interventions aimed at preventing intracellular Ca2+ overload improve recovery after cardioplegic arrest. The beneficial effects of halothane could be further improved by HOE 694.  相似文献   
79.
Transesophageal echocardiography is recommended to monitor left ventricular (LV) size and function in various operations. Generally, two‐dimensional (2D) methods are applied intraoperatively. The aim of this study was to compare the accuracy and feasibility of 6 commonly used 2D methods to assess LV function during surgery. LV function in 120 consecutive patients was evaluated. Real time three‐dimensional transesophageal echocardiograpy (3DTEE) served as reference. End‐diastolic and end‐systolic volumes and ejection fraction (EF) were analyzed with Simpson's method of discs (monoplane [MP] and biplane [BP]), eyeball method, Teichholz' method, and speckle tracking (ST) methods. Furthermore, fractional area change (FAC) and peak systolic pressure rise (dP/dt) were determined. Each 2D method was evaluated regarding correlation and agreement with 3DE, intra‐ and interobserver variability and the time required for evaluation. Simpson BP showed the strongest correlation and best agreement with 3DE for EF (limits of agreement 3.7 ± 11.6%) and volumes. Simpson MP showed similar agreement with 3DE compared to ST (2.8 ± 14.5% vs. 2.0 ± 15.3% and 3.8 ± 14.4% vs. 1.9 ± 15.6%, respectively). Both the eyeball method and Teichholz' method showed wide limits of agreement (?1.5 ± 18.2% and 5.2 ± 22.1%, respectively). DP/dt did not correlate with 3DE. FAC and ST FAC showed similar agreement. Application of 3DE (429 ± 108 seconds) took the longest time, and the eyeball method took the shortest time (8 ± 5 seconds) for analysis. Simpson BP is the most accurate intraoperative 2D method to evaluate LV function, followed by long‐axis MP evaluations. Short‐axis views were less accurate but may be suited for monitoring. We do not recommend using dP/dt.  相似文献   
80.
OBJECTIVE: Animal studies have demonstrated that reperfusion disorders occurring after cardiac arrest affect outcome. Reperfusion injury can be caused by activation of complement, polymorphonuclear leukocytes (PMN), and PMN-endothelial interaction. We studied different specific markers of these processes during and after cardiopulmonary resuscitation in humans. DESIGN: Prospective clinical trial. SETTING: University hospital. PATIENTS: A total of 55 patients who underwent out-of-hospital cardiopulmonary resuscitation for nontraumatic causes. INTERVENTIONS: Blood samples were drawn immediately, 15 mins, and 30 mins after initiation of cardiopulmonary resuscitation. In the case of restoration of spontaneous circulation, additional blood samples were taken at serial time points until 7 days after cardiac arrest. MEASUREMENTS AND MAIN RESULTS: A marked activation of complement and PMN was found in all patients investigated. Serum concentrations of specific activation markers of the complement system, anaphylatoxin C3a and the soluble membrane attack complex SC5b-9, and PMN elastase were increased during cardiopulmonary resuscitation and for 相似文献   
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