ABSTRACT
Rapid, inexpensive, robust diagnostics are essential to control the spread of infectious diseases. Current state of the art diagnostics are highly sensitive and specific, but slow, and require expensive equipment. We developed a molecular diagnostic test for SARS-CoV-2, FIND (Fast Isothermal Nucleic acid Detection), based on an enhanced isothermal recombinase polymerase amplification reaction. FIND has a detection limit on patient samples close to that of RT-qPCR, requires minimal instrumentation, and is highly scalable and cheap. It can be performed in high throughput, does not cross-react with other common coronaviruses, avoids bottlenecks caused by the current worldwide shortage of RNA isolation kits, and takes ~45 minutes from sample collection to results. FIND can be adapted to future novel viruses in days once sequence is available. One sentence summarySensitive, specific, rapid, scalable, enhanced isothermal amplification method for detecting SARS-CoV-2 from patient samples.
ABSTRACT
<p><b>OBJECTIVE</b>To better define the effect of JAK2V617F mutant allele burden on clinical presentation of patients with essential thrombo cythamia (ET), especially thrombosis.</p><p><b>METHODS</b>Two ml of heparin anti-coagulated bone marrow was collected from 229 ET cases, who were diagnosed and treated in the First People's Hospital of Yunnan Province during 2013.10 to 2016.12. and then the mononuclear cells were separated by Red Blood Cell Lysis Buffer, genomic DNA was extracted from mononuclear cells by using a commercial DNA isolation kit and amplified by allele specific polymerase chain reaction (PCR). According to the size of molecular weight, the amplified products were separated by electrophoresis on a 2% agarose gel to screen the JAK2V617F mutation, then the JAK2V617F mutation burden was detected by real-time polymerase chain reaction (RT-PCR) in 120 patients with JAK2V617F mutation. Meanwhile, these samples were sequenced in order to verify the accuracy of the PCR screewing.</p><p><b>RESULTS</b>ET patients with thrombotic events had significantly higher JAK2V617F allele burden than those without thrombosis (23.2% vs 14.2%) ( P<0.05). Meanwhile, ET patients showed increased JAK2V617F allele burden in the group with higher leukocytosis (WBC > 10×10/L) (P<0.001) and hemoglobin (> 150 g/L) (P<0.05). JAK2V617F mutation burden in 17 patients with splenomegaly was higher than that in 45 patients without splenomegaly (28.1% vs 11.8%) (P<0.05). but the JAK2V617F mutation burden was regatively correlated with platelet count (P<0.05). On the other hand, no correlation was found between JAK2V617F mutation burden and sex (P > 0.05). Univariate analysis showed that the JAK2V617F allele burden did not affect survival. Multivariable analysis showed that prognostic variable including WBC counts, hemoglobin level, age, sex, and splenomegaly not affected survival, (P > 0.05).</p><p><b>CONCLUSION</b>The clinical presentations of ET patients, such as WBC counts, hemoglobin level and splenomegaly, are influenced by the JAK2V617F mutation burden. ET patients with thrombotic events has significantly higher JAK2V617F allele burden than those in ET palients without thrombosis.JAK2V617F mutation burden has no relations with sex and age..</p>
ABSTRACT
BACKGROUND:It has been reported that 70% of patients with chronic myeloid leukemia (CML) are negative for cytogenetic and genetic markers within 1-5 months after allogeneic hematopoietic stem cell transplantation (allo-HSCT),but there are still some patients who have repeatedly varied outcomes in cytogenetic and genetic marker detection.Overall,the negative rate is up to 89.5% at 3-12 months after allo-HSCT.OBJECTIVE:To monitor the changes in cytogenetic and genetic marker expression and to explore the prognostic significance in CML patients undergoing allo-HSCT.METHODS:Seventeen CML patients who had undergone allo-HSCT were enrolled.Chromosome G banding pattern of the bone marrow from these patients were analyzed using short-term culture method and direct method at 30 days,2,3,4,6,12,24,36,48,60,72 months after allo-HSCT.Dual-color fluorescence in situ hybridization was used to detect bcr-abl fusion gene;bcr-abl expressions in primary bone marrow ceils from CML patients were detected using RQ-PCR.Results and conclusion:There were 8/17 cases of male patient/male donor and 7/17cases of male patient/female donor (compatriots).46XX karyotype (women) was detected by multiple reexaminations after transplantation,and there was no Y chromosome or other aberration of chromosome karyotype in their karyotype.Among the 17 cases,1 case of female patient/female donor (compatriots) and 1 case of female patient/male donor (unrelated) manifested 46 XY chromosome karyotype and bcr-abl positive at 1 month after transplantation;after 4 months,these two cases still maintained 46 XY chromosome karyotype but bcr-abl negative;after 4-96 months,the karyotype continued to remain as 46 XY,and bcr-abl (-).Among the 17 cases,1 case of male patient/male donor of full-matched compatriot (brother) manifested that Ph chromosomal bcr-abl gene continuously expressed within 1-12 months after allo-HSCT;then the cases was given donor lymphocyte infusion,and the bcr-abl expression returned to be negative at 48 months after transplantation.To conclude,chromosomal karyotype analysis and bcr-abl fusion gene monitoring provide important reference value for subsequent treatment options and prognosis judgment for CML patients with allo-HSCT.