Effects of hemoglobin-based oxygen carriers on blood coagulation.

For many decades, Hemoglobin-based oxygen carriers (HBOCs) have been central in the development of resuscitation agents that might provide oxygen delivery in addition to simple volume expansion. Since 80% of the world population lives in areas where fresh blood products are not available, the application of these new solutions may prove to be highly beneficial (Kim and Greenburg 2006). Many improvements have been made to earlier generation HBOCs, but various concerns still remain, including coagulopathy, nitric oxide scavenging, platelet interference and decreased calcium concentration secondary to volume expansion (Jahr et al. 2013). This review will summarize the current challenges faced in developing HBOCs that may be used clinically, in order to guide future research efforts in the field

Outcomes of Genetic Testing in a Genitourinary Genetics Clinic

Several known hereditary cancer syndromes confer an increased risk for genitourinary (GU)related malignancies. Various guidelines indicate when to refer patients to genetic counseling for GU-related hereditary cancer syndromes but there is limited research on the clinical picture of these patients, including their cancerous and non-cancerous features, the genetic testing strategy for this population, and the probability of having a positive germline mutation if testing is performed. The purpose of this study is to determine the most common indications for ordering genetic testing in a GU Genetics Clinic and evaluate whether there is a relationship between the indication for genetic testing and genetic testing outcome. An institutional review board-approved retrospective chart review was performed for 220 patients seen in the GU Genetics Clinic at M.D. Anderson Cancer Center. Patients were stratified into groups based on their indication for genetic testing and an exact binomial test was used to compare the proportion of patients with a positive genetic test from various groups. The majority of patients (92%) were seen for genetic evaluation related to either renal cell carcinoma (RCC) or prostate cancer. Among patients seen for RCC-related evaluation (N=107), meeting published clinical criteria for a hereditary RCC syndrome significantly predicted positive genetic testing (

Factors Influencing Uptake of Risk-Reducing Salpingo-Oophorectomy by BRCA1 and BRCA2 Mutation Carriers

Germline mutations in the BRCA1 and BRCA2 genes are associated with significantly increased risks for ovarian cancer. The National Comprehensive Cancer Network (NCCN) currently recommends that female BRCA mutation carriers undergo risk-reducing salpingo-oophorectomy (RRSO) after age 35; however, not all women elect this option. The purpose of this study was to prospectively survey women with BRCA mutations currently undergoing ovarian cancer screening about their intention to have an RRSO and the various factors influencing their decision. Of the 26 women who completed our survey, 26 (100%, CI: 86.8-100) plan to undergo an RRSO in their lifetime. The average woman reported 6.7 motivations and 2.9 barriers to RRSO, indicating that in our population women tend to have more reasons for electing, rather than avoiding, this surgery. We further found that while most women appeared to share the same motivations for surgery, they often had unique barriers that were not common to others. The most important reasons in favor of surgery included a desire to reduce one’s risk for ovarian cancer and live longer for family members. The most important barrier to RRSO was fear of the symptoms related to menopause. We believe these results will assist healthcare providers when discussing the option of RRSO with BRCA mutation carriers undergoing ovarian cancer screening

Polyethylene Glycol Camouflaged Earthworm Hemoglobin.

Nearly 21 million components of blood and whole blood and transfused annually in the United States, while on average only 13.6 million units of blood are donated. As the demand for Red Blood Cells (RBCs) continues to increase due to the aging population, this deficit will be more significant. Despite decades of research to develop hemoglobin (Hb) based oxygen (O2) carriers (HBOCs) as RBC substitutes, there are no products approved for clinical use. Lumbricus terrestris erythrocruorin (LtEc) is the large acellular O2 carrying protein complex found in the earthworm Lumbricus terrestris. LtEc is an extremely stable protein complex, resistant to autoxidation, and capable of transporting O2 to tissue when transfused into mammals. These characteristics render LtEc a promising candidate for the development of the next generation HBOCs. LtEc has a short half-life in circulation, limiting its application as a bridge over days, until blood became available. Conjugation with polyethylene glycol (PEG-LtEc) can extend LtEc circulation time. This study explores PEG-LtEc pharmacokinetics and pharmacodynamics. To study PEG-LtEc pharmacokinetics, hamsters instrumented with the dorsal window chamber were subjected to a 40% exchange transfusion with 10 g/dL PEG-LtEc or LtEc and followed for 48 hours. To study the vascular response of PEG-LtEc, hamsters instrumented with the dorsal window chamber received multiple infusions of 10 g/dL PEG-LtEc or LtEc solution to increase plasma LtEc concentration to 0.5, then 1.0, and 1.5 g/dL, while monitoring the animals' systemic and microcirculatory parameters. Results confirm that PEGylation of LtEc increases its circulation time, extending the half-life to 70 hours, 4 times longer than that of unPEGylated LtEc. However, PEGylation increased the rate of LtEc oxidation in vivo. Vascular analysis verified that PEG-LtEc showed the absence of microvascular vasoconstriction or systemic hypertension. The molecular size of PEG-LtEc did not change the colloid osmotic pressure or blood volume expansion capacity compared to LtEc, due to LtEc's already large molecular size. Taken together, these results further encourage the development of PEG-LtEc as an O2 carrying therapeutic

Rapid detection of BRCA1/2 recurrent mutations in Chinese breast and ovarian cancer patients with multiplex SNaPshot genotyping panels.

BRCA1/2 mutations are significant risk factors for hereditary breast and ovarian cancer (HBOC), its mutation frequency in HBOC of Chinese ethnicity is around 9%, in which nearly half are recurrent mutations. In Hong Kong and China, genetic testing and counseling are not as common as in the West. To reduce the barrier of testing, a multiplex SNaPshot genotyping panel that targeted 25 Chinese BRCA1/2 mutation hotspots was developed, and its feasibility was evaluated in a local cohort of 441 breast and 155 ovarian cancer patients. For those who tested negative, they were then subjected to full-gene testing with next-generation sequencing (NGS). BRCA mutation prevalence in this cohort was 8.05% and the yield of the recurrent panel was 3.52%, identifying over 40% of the mutation carriers. Moreover, from 79 Chinese breast cancer cases recruited overseas, 2 recurrent mutations and one novel BRCA2 mutation were detected by the panel and NGS respectively. The developed genotyping panel showed to be an easy-to-perform and more affordable testing tool that can provide important contributions to improve the healthcare of Chinese women with cancer as well as family members that harbor high risk mutations for HBOC

NGS Panels applied to Hereditary Cancer Syndromes

Cancer is among the leading causes of morbidity and mortality worldwide (Okur et al, 2017). Germline pathogenic variants for monogenic, highly penetrant cancer susceptibility genes are observed in 5%–10% of all cancers (Lu et al, 2014). Hereditary cancers due to monogenic causes are characterized by earlier age of onset, other associated cancers, and often a family history of specific cancers. From the clinical perspective, it is important to recognize the affected individuals to provide them the best clinical management (Hennessy et al, 2010; Ledermann et al, 2014; Pennington et al, 2014) and to identify at-risk family members who will benefit from predictive genetic testing and enhanced surveillance, including early detection and/or risk reduction measures (Kurian et al, 2010; Okur et al, 2017). Germline variants identified in major cancer susceptibility genes associated with hereditary breast or ovarian cancer (HBOC) or hereditary colorectal cancer (HCRC), also account for 5-10% of the patients with these cancers. In the last years, new susceptibility genes, with different penetrance degrees, have been identified. Variants in any of those genes are rare and classical methodologies (e.g. Sanger sequencing - SS) are time consuming and expensive. Next-generation sequencing (NGS) has several advantages compared to SS, including the simultaneous analysis of many samples and sequencing of a large set of genes, higher sensitivity (down to 1% vs 15-20% in SS), lower cost and faster turnaround time, reasons that make NGS the best approach for molecular diagnosis. It is possible nowadays to choose between whole-genome sequencing (WGS), whole-exome sequencing (WES) and NGS limited to a set of genes (NGS-Panel). In cases where a suspected genetic disease or condition has been identified, targeted sequencing of specific genes or genomic regions is preferred (Grada et al, 2013). For that reason, we use NGS-Panel approach using TruSight Cancer (Illumina) to sequence DNA extracted from blood samples of patients with personal and/or familiar history of cancer. This hereditary cancer gene panel sequences 94 genes associated with both common (e.g., breast, colorectal) and rare hereditary cancers and allows the creation of virtual gene panels according to each phenotype or disease under study. NGS workflow analysis (Figure 1) includes five steps: quality assessment of raw data, read alignment to a reference genome, variant identification/calling, variant annotation and data visualization (Pabinger et al, 2013). The establishment of the most appropriate bioinformatics pipeline is crucial in order to achieve the best results. NGS data allows the identification of several types of variants like single nucleotide variants (SNVs), small insertions/deletions, inversions and also copy number variants (CNVs).FCT - UID/BIM/0009/2016info:eu-repo/semantics/publishedVersio

Interference of bovine hemoglobin-based oxygen carrier-201 (Hemopure) on four hematology analyzers

Introduction: Hemoglobin-based oxygen carriers, for example HBOC-201 (Hemopure), are aimed to bridge acute anemia when blood transfusion is not available or refused by the patient. However, since HBOC-201 appears free in plasma, it interferes with laboratory tests. This study presents an overview of HBOC-201 interference on four commonly used hematology analyzers and suggests treatment monitoring possibilities. Methods: Blood samples were spiked with therapeutic doses of HBOC-201 and nine hematology parameters were measured with the Sysmex XN-20, Siemens Advia 2120i, Abbott Alinity Hq and Abbot Cell Dyn Sapphire hematology analyzers. The results were compared to control samples and the bias was determined. Results: Most parameters, including all cell counts, hematocrit and MCV, showed a non-significant bias compared to control. However, the standard, total hemoglobin (Hb) measurement as well as MCH and MCHC showed poor agreement with control, as HBOC-201 was included in this measurement. Yet, the flow cytometry-based Hb method quantified intracellular Hb in spiked samples, excluding HBOC-201. Conclusion: Of all included hematology parameters, only total Hb and the associated MCH and MCHC suffered from interference. In contrast, the flow cytometry-based Hb measurement provided an accurate measure of intracellular Hb. The difference between total Hb and cellular Hb represents the HBOC-201 concentration and can be used to monitor HBOC-201 treatment.</p

Polymerized bovine hemoglobin solution as a replacement for allogeneic red blood cell transfusion after cardiac surgery: Results of a randomized, double-blind trial

AbstractBackground: Blood loss leading to reduced oxygen-carrying capacity is usually treated with red blood cell transfusions. This study examined the hypothesis that a hemoglobin-based oxygen-carrying solution can serve as an initial alternative to red blood cell transfusion. Methods: In a randomized, double-blind efficacy trial of HBOC-201, a total of 98 patients undergoing cardiac surgery and requiring transfusion were randomly assigned to receive either red blood cell units or HBOC-201 (Hemopure; Biopure Corporation, Cambridge, Mass) for the first three postoperative transfusions. Patients were monitored before and after transfusion, at discharge, and at 3 to 4 weeks after the operation for subsequent red blood cell use, hemodynamics, and clinical laboratory parameters. Results: The use of HBOC-201 eliminated the need for red blood cell transfusions in 34% of cases (95% confidence interval 21%-49%). Patients in the HBOC group received a mean of 1.72 subsequent units of red blood cells; those who received red blood cells only received a mean of 2.19 subsequent units (P =.05). Hematocrit values were transiently lower in the HBOC group but were similar in the two groups at discharge and follow-up. Oxygen extraction was greater in the HBOC group (P =.05). Mean increases in blood pressure were greater in the HBOC group, but not significantly so. Conclusion: HBOC-201 may be an initial alternative to red blood cell transfusions for patients with moderate anemia after cardiac surgery. In a third of cases, HBOC-201 eliminated the need for red blood cell transfusion, although substantial doses were needed to produce this modest degree of blood conservation.J Thorac Cardiovasc Surg 2002;124:35-4