Fe3+及血红蛋白铁对眼源性蜡样芽胞杆菌生长能力的影响

目的 探讨Fe³⁺及血红蛋白铁对眼源性蜡样芽胞杆菌生长能力的影响。方法 实验研究。收集2011年6月至2017年2月温州医科大学附属眼视光医院外伤性蜡样芽胞杆菌性眼内炎患者26例并分离出蜡样芽胞杆菌26株。根据患者治疗后有无光感将菌株分为有光感（LP）组和无光感（NLP）组,以蜡样芽胞杆菌模式菌株ATCC14579作为对照组,检测不同菌株在缺铁环境、不同Fe³⁺浓度环境、富含Hb环境中生长的光密度（OD）值。采用独立样本t检验对数据进行统计分析。结果 26株眼部来源的蜡样芽胞杆菌在缺铁环境中生长的OD值小于模式菌株ATCC14579（t=54.098,P<0.001）。在一定范围内（0~500 μmol/L）增加Fe³⁺浓度,菌株生长的OD值随之逐渐增加,当Fe³⁺浓度高于1 000 μmol/L时,细菌生长的OD值开始下降。在Fe³⁺或血红蛋白铁为主要铁资源的环境中,NLP组菌株生长的OD值均高于LP组（t=2.618,P=0.015;t=2.202,P=0.037）。结论 眼源性蜡样芽胞杆菌的生长对Fe³⁺具有较强的依赖性;在Fe³⁺或血红蛋白铁为主的铁资源环境中生长较快的菌株感染患者,其临床预后较差。     

Higher executive abilities following a blood transfusion in children and young adults with sickle cell disease

Individuals with sickle cell disease (SCD) experience cognitive deficits; however, it remains unclear whether medical treatments for SCD improve cognition. Given that executive abilities are typically impaired in individuals with SCD, they were the focus of the current study. Our primary hypothesis was that executive abilities would be higher acutely soon after a blood transfusion in children and young adults with SCD. We used tests from the NIH Toolbox to assess executive abilities in 27 participants with SCD receiving chronic transfusion in comparison to 34 participants with SCD receiving hydroxyurea (HU) and 41 non‐SCD demographically matched controls, all of whom were tested at two time points. Participants in the transfusion group completed cognitive testing within 3 days after a transfusion (soon after transfusion) and then within 3 days before their next transfusion (long after transfusion) over an interval of 3‐7 weeks. We found that executive abilities were significantly poorer for the transfusion and HU groups than for the control group. In support of our primary hypothesis, executive abilities for the transfusion group were significantly better soon after a transfusion compared to long after a transfusion, χ²(1) = 17.8, P < .0001. Our results demonstrate that executive abilities were higher acutely following a blood transfusion. These findings have implications for daily functioning, medical decision making, and academic achievement in children and young adults with SCD.     

Hb Manukau [β67(E11)Val → Gly; HBB: c.203T>G]: The Role of Genetic Testing in the Diagnosis of Idiopathic Hemolytic Anemia

The increasing availability of DNA sequencing of globin genes has improved our ability to detect conditions that were presumed to be extremely rare. These conditions may remain undiagnosed due to unfamiliarity with clinical presentation, relative unavailability of advanced diagnostic alternatives, or may defy detection by being electrophoretically silent or extreme instability rendering their presence to be below detection level. Genetic studies were pursued in a mother and daughter with severe hemolytic anemia as initial testing failed to be diagnostic. DNA sequence analysis of the β-globin gene identified Hb Manukau [β67(E11)Val?→?Gly; HBB: c.203T?>?G], an extremely unstable hemoglobin (Hb) variant. This is the second family described with this condition (first in the western hemisphere). An astute clinician may benefit from being persistent and pursuing additional testing including molecular genetic characterization where clinical suspicion remains high.     

An audit on diabetes management in Asian patients treated by specialists: the Diabcare-Asia 1998 and 2003 studies

ABSTRACT

Objective: To collect information on diabetes management, including psychosocial aspects, in patients managed by specialists 5 years after they were first surveyed in 1998.

Methods: Data on demography, diabetes status, management and complications were collected via medical records, interview and laboratory assessments. HbA_1c was analysed by a central laboratory prospectively.

Results: Patient profile was similar in the 1998 (N = 21 838) and 2003 cohorts (N = 15 549): 95% were diagnosed as type 2 diabetes mellitus and were obese (BMI ≈ 25 kg/m²). Glycaemic control was unsatisfactory in many patients (mean HbA_1c ≈ 8%; fasting glucose ≈ 9 mmol/L). Lipids were well-controlled but hypertension was not. The incidence of neuropathy (≈ 33%) and cataract (≈ 27%) were high. The majority (≈ 71%) of patients in both cohorts were treated with oral antidiabetic drug (OAD) monotherapy; ≈ 24% were on insulin therapy. Approximately half of the 2003 cohort reported a healthy state of well-being. Quality of life did not appear to have suffered as a result of having diabetes. However, many patients were worried about hypoglycaemic risk (53.9%) or worsening of diabetes (45.8%) and insulin initiation (64.5%).

Conclusions: Although both cohorts were separate cross-sectional studies of diabetes management status in Asia, the results showed that the demography profile, glycaemic control and cardiovascular risk factors were remarkably similar in both cohorts 5 years after the first survey. More concerted efforts are needed to increase diabetes awareness and education.     

Investigation on the interaction of the toxicant,gentian violet,with bovine hemoglobin

Gentian violet (GV) is a well-known triarylmethane dye that is used in aquacultural, industrial and medicinal fields. But concerns in growing number have been paid to its potential health problems to human beings and its hazardous effects to environment. Herein, the toxic interaction of GV with bovine hemoglobin (BHb) was investigated by a series of spectroscopic methods and molecular modeling method. The fluorescence emission profile exhibited a remarkable quenching upon addition of GV to the buffered aqueous solution of BHb and the analysis of results revealed the dominant role of static quenching mechanism in GV–BHb interaction. The negative ΔH and positive ΔS values demonstrated that the electrostatic interactions mainly stabilized this toxicantprotein complex. Synchronous fluorescence, UV–Vis absorption and CD spectroscopic studies proved that the conformational change of BHb was induced by GV’s combination. Molecular modeling studies exhibited the binding mode of GV–BHb complex and the detailed information of related driving forces. During the ¹H nuclear magnetic resonance spectra (¹H NMR) study, the chemical shift perturbation and spin–lattice relaxation times of different protons were further used to investigate the interaction of GV with BHb and the results indicated that GV bound orientationally to BHb.     

Fetal Hemoglobin in the Maternal Circulation – Contribution of Fetal Red Blood Cells

The major hemoglobin (Hb) during fetal life is fetal Hb (Hb F). It is mostly replaced by adult Hbs before birth and during the first year of life. In adults, where Hb F comprises <2.0% of the total Hb, it is not homogenously distributed among the red blood cells (RBCs) but is concentrated in a few RBCs, termed F-cells. Interestingly, for reasons that are unclear, Hb F increases in the maternal circulation during pregnancy. This increased Hb F could have two potential origins that are not mutually exclusive: A) maternal origin, due to inducing environment of Hb F in the maternal erythroid precursors; B) fetal origin, due to fetal cells crossing the placenta and entering the maternal circulation. The question we present herein is whether the observed increased Hb F in the maternal circulation during pregnancy is, at least partially, derived from the fetal origin. Peripheral blood was obtained from normal neonates (1–3 days old), adult men and pregnant and non pregnant women. The RBCs were stained for Hb F and carbonic anhydrase (CA) using a fetal cell count kit and analyzed by flow cytometry. Fetal and adult F-cells were distinguished by their expression of Hb F and CA. Fetal F-cells were Hb F⁺⁺/CA^?, while adult F-cells were Hb F⁺/CA⁺. Comparing pregnant and non pregnant women samples (n?=?10), we found six samples of pregnant women with 0.2–1.7% fetal cells, but none in the non pregnant group. These results support the possibility that at least part of the increase in Hb F during pregnancy is due to fetal cells entering the maternal circulation.     

HbA1c及CRP在妊娠期糖尿病治疗中的意义

目的评估糖化血红蛋白(HbA1c)及C反应蛋白(CRP)测定在妊娠期糖尿病血糖控制及治疗中的指导意义。方法选取2016年7月—2017年2月于本院妇产科行产前检查的孕24~28周孕妇行空腹血糖(FBG)、75 g口服糖耐量试验(OGTT)、HbA1c及CRP检查,分为正常妊娠者(对照组),妊娠期糖耐量受损者(GIGT组),妊娠期糖尿病者(GDM组)各40例。对受试对象孕36~38周再次进行FBG、HbA1c及CRP复查,比较各项指标及转归。结果孕24~28周GIGT组及GDM组FBG、HbA1c及CRP指标均高于对照组(P<0.05);进行饮食控制及(或)胰岛素治疗后GIGT组及GDM组各指标均有不同程度下降,P<0.05,GIGT组部分孕妇可恢复至正常值。结论HbA1c检测快速简便,联合CRP有助于妊娠期糖尿病的临床检测及诊断,可用于孕期血糖控制的跟踪观察。     

Preliminary Risk assessment for Acrylamide and Peripheral Neuropathy

Acrylamide (ACM) is a high-volume industrial chemical with diverse uses in manufacturing, construction and laboratory research. ACM is a well-established neurotoxic agent causing peripheral neuropathy with impairment in the arms and legs of exposed workers, most thoroughly studied in Swedish tunnel workers exposed to ACM grouting. A quantitative risk assessment was performed to assess ACM risk to workers. Using data from a published paper investigating peripheral neuropathies in Chinese chemical workers, estimates of exposure response for vibration perception threshold and nerve conduction velocities were calculated, based on hemoglobin adducts and air concentrations as exposure metrics. The benchmark dose procedure was applied in order to calculate excess risks of impairment, defined as adverse performance exceeding the 95^th percentile in unexposed populations, at various concentrations of airborne ACM exposure. Under the assumptions in this risk assessment, after three years of inhalation exposure at 0.3 mg/m³, the excess attributable impairment manifest in vibration perception and nerve conduction velocity is estimated to occur in 1-2% of workers. For 10 years at 0.3 mg/m³ ACM inhalation (equivalent to 3 years at 1.0 mg/m³) the excess prevalence of impairment would be 2-14% of workers, assuming the effect continues to accrue linearly in time. Using published data, the risks of impairment from peripheral neuropathy attributable to exclusively airborne ACM exposure can be predicted for exposure periods less than 10 years. The risks associated with dermal and airborne ACM exposures can be estimated by characterizing working process environments using ACM Hb-adduct levels and possibly monitored with urinary biomarkers.     

Physical activity as a proxy to ameliorate inflammation in patients with type 2 diabetes and periodontal disease at high cardiovascular risk

While the beneficial impact of physical activity has been ascertained in a variety of pathological scenarios, including diabetes and low-grade systemic inflammation, its potential remains still putative for periodontal health. Periodontal disease has been associated with inflammatory systemic alterations, which share a common denominator with type 2 diabetes mellitus and cardiovascular disease. Physical exercise, along with nutritional counseling, is a cornerstone in the treatment and prevention of type 2 diabetes, also able to reduce the prevalence of periodontal disease and cardiovascular risk. In addition, considering the higher incidence of periodontitis in patients with type 2 diabetes compared to healthy controls, the fascinating research question would be whether physical activity could relieve the inflammatory pressure exerted by the combination of these two diseases. This multi-disciplinary viewpoint discusses available literature in order to argument the hypothesis of a “three–way relationship” linking diabetes, periodontitis, and physical activity.