Awareness of venous thromboembolism and thromboprophylaxis among hospitalized patients: a cross-sectional study

Background

Patient awareness of venous thromboembolism (VTE) and thromboprophylaxis is essential for their safety. In this study, we evaluated patients’ awareness of VTE and their perceptions of thromboprophylaxis.

Methods

We administered a cross-sectional survey to patients hospitalized at the King Abdulaziz Medical City, Riyadh, Saudi Arabia.

Results

Of 190 patients approached, 174 completed the survey, constituting a response rate of 95%. Most participants (72%) were receiving thromboprophylaxis. However, only 32 and 15% reported knowledge of deep vein thrombosis (DVT) and pulmonary embolism (PE), respectively. Fifty-five percent of participants with knowledge of DVT identified swelling of the leg as a symptom. Risk factors for blood clot development were correctly identified by about half of participants, although most agreed that blood clots can cause death (77%). The level of awareness of DVT or PE did not significantly differ by respondents’ demographics. However, awareness of DVT or PE was significantly higher among those with a personal or family history of VTE. Participants had positive perceptions of thromboprophylaxis and were satisfied with treatment (> 69%), but perceived its adverse effects less favorably and reported lower satisfaction with the information provided about DVT and PE (46%).

Conclusion

This study demonstrates the lack of awareness of VTE, DVT, and PE among hospitalized patients. More attention must be paid to patient education to ensure safe and high-quality patient care.

     

Hb Lake Tapawingo [α46(CE4)Phe→Ser; HBA2:c.140T>C]: a new unstable α chain hemoglobin variant associated with low systemic arterial saturation

A new unstable α-globin variant was detected in a child with hypoxemia and anemia. The child's mother was found to carry the same mutation. The hemoglobin (Hb) variant co-eluted with Hb A(2) by cation exchange high performance liquid chromatography (HPLC) and appeared cathodal to Hb A and anodal to Hb F by isoelectric focusing. It represented less than 20% of the total Hb and was unstable by isopropanol testing. Gene sequencing identified a missense mutation on the α2 gene [HBA2:c.140T>C]. Oxygen dissociation and P(50) test results were normal.     

Characterization of hemoglobin bassett (alpha94Asp-->Ala), a variant with very low oxygen affinity

Hemoglobin (Hb) Bassett, an abnormal Hb variant with a markedly reduced oxygen affinity, was discovered in a Caucasian (Anglo-Saxon) male child who experienced episodes of cyanosis. Cation-exchange and reversed-phase (RP) high-performance liquid chromatography (HPLC) showed that the patient has an abnormal Hb, with a mutation in the alpha-globin. Tryptic peptide digest of the abnormal alpha-globin with subsequent HPLC analysis revealed abnormal elution of the alpha-T11 peptide. Further studies with Edman sequencing and electrospray mass spectrometry of tryptic peptide alpha-T11, as well as structural analysis by X-ray crystallography revealed an Asp-->Ala substitution at the alpha94 (G1) position, a match for Hb Bassett. Detailed functional studies showed that this Hb variant had a markedly reduced oxygen affinity (P(50) at pH 7.0 = 22 mmHg; Hb A P(50) = 10.5 mmHg), reduced Bohr effect (-0.26 compared to - 0.54 in Hb A), and low subunit cooperativity (n = 1.4, compared to 2.6 in Hb A). X-ray crystallography results explain the probable effects of the structural modification on the oxygen-binding properties of this Hb variant.     

2'-O-methoxyethyl splice-switching oligos correct splicing from IVS2-745 β-thalassemia patient cells restoring hemoglobin A production and chain rebalance

β-thalassemia is a disorder caused by altered hemoglobin protein synthesis which affects individuals worldwide. Severe forms of the disease, left untreated, can result in death before the age of 3 years.¹ The standard of care consists of chronic and costly palliative treatment by blood transfusion combined with iron chelation. This dual approach suppresses anemia and reduces iron-related toxicities in patients. Allogeneic bone marrow transplant is an option, but limited by the availability of a highly compatible hematopoietic stem cell donor. While gene therapy is being explored in several trials, its use is highly limited to developed regions with centers of excellence and well-established healthcare systems. ² Hence, there remains a tremendous unmet medical need to develop alternative treatment strategies for b-thalassemia.³ Occurrence of aberrant splicing is one of the processes that affects b-globin synthesis in b-thalassemia. The (C>G) IVS2-745 is a splicing mutation within intron 2 of the b-globin (HBB) gene. It leads to an aberrantly spliced mRNA that incorporates an intron fragment. This results in an in-frame premature termination codon that inhibits b-globin production. Here, we propose the use of uniform 2''-O-methoxyethyl (2''-MOE) splice switching oligos (SSO) to reverse this aberrant splicing in the pre-mRNA. With these SSO we show aberrant to wild-type splice switching. This switching leads to an increase of adult hemoglobin up to 80% in erythroid cells from patients with the IVS2-745 HBB mutation. Furthermore, we demonstrate a restoration of the balance between b-like- and α-globin chains, and up to an 87% reduction in toxic heme aggregates. While examining the potential benefit of 2''-MOE-SSO in a mixed sickle-thalassemic phenotypic setting, we found reduced sickle hemoglobin synthesis and sickle cell formation due to HbA induction. In summary, 2''-MOE-SSO are a promising therapy for forms of b-thalassemia caused by mutations leading to aberrant splicing.     

Self-expanding metal stenting for obstructing left colon cancer: A district hospital experience

Stenting of malignant colonic obstructions using self-expanding metal stents (SEMS) is commonly used for palliation and can be used as an interim procedure prior to definitive surgery. We retrospectively reviewed prospectively collected data from all consecutive colonic stenting procedures undertaken between September 2007 and December 2014 at a district general hospital. Technical and clinical success rates, mortality, colonic perforation, and other complications were documented and analyzed. Sixty-four colonic stenting procedures were undertaken. Fifty-three (83 %) were for palliation and eleven (17 %) were performed as a bridge to definitive surgery. Technical (98.4 %) and clinical (89.9 %) success rates were excellent. The single documented failure was secondary to complete luminal obstruction. Three stent occlusions (4.6 %), one colonic perforation (1.5 %), and one migration were encountered. There were no procedure-related deaths. Colonic stenting for obstructing left-sided colon cancer is a safe and effective procedure, even in the district general hospital setting. The use of SEMS as a bridge to elective surgery balances surgical and oncological considerations and, therefore, is most appropriate for high surgical risk patients in this setting.     

X线颅颌面影像自动识别定点研究

目的 研究计算机对X线颅颌面影像的自动识别定点。方法 ①X线颅颌面影像的自动识别:X线颅颌侧位定位片经扫描仪将图像输入计算机,图像处理后重建该图象。②X线颅颌面影像的自动定点:以FH平面为基准进行分区,运用三次样条插值法使曲线光滑,使用轮廓跟踪技术进行标志点的寻找,使用拟合逼近进行拟圆,进行二值化确定两曲线的交点。结果提取出了颅颌面软组织外轮廓、硬组织外轮廓及部分内部结构,提取出了颅颌面31个标志点。结论进行了计算机对X线颅颌面影像轮廓和特征点的识别研究,为全自动识别分析奠定了基础。     

Tissue accumulation of lipoprotein associated toxaphene in normo- and hypolipidemic mice

Normo- and hypolipidemic mice were given a single i.v. injection of¹⁴C-toxaphene associated with low density lipoprotein (LDL), high density lipoprotein (HDL) or dimethyl sulfoxide (DMSO). The tissue distribution of radioactivity was studied 20 min and 4 h after the application. In the normolipidemic mice at 20 min postinjection there was high uptake of the¹⁴C-toxaphene preparations in the liver and adrenals followed after 4 h by a redistribution to the adipose tissues. In the hypolipidemic mice, proportionally less label accumulated initially in the liver and adrenals while more radioactivity was seen in the kidneys and heart. The radioactivity then redistributed to the liver with a very small uptake in the adipose tissue compared to the normolipidemic mice after 4 h. The results indicate that changes in the lipid pattern, e.g. hypolipidemic conditions, may influence the tissue distribution of lipophilic xenobiotics.