Robert S. Makar

Testing only donors with a prior history of pregnancy or transfusion is a logical and cost-effective transfusion-related acute lung injury prevention strategy.

BACKGROUND: Transfusion‐related acute lung injury (TRALI) is the leading cause of transfusion‐related fatality reported to the Food and Drug Administration. Donor screening may reduce TRALI risk. This study sought to compare the efficacy and safety of different TRALI risk‐reduction strategies at a hospital‐based donor center.

Tuba stimulates intracellular N-WASP-dependent actin assembly

Tuba is a multidomain scaffolding protein that links cytoskeletal dynamics and membrane trafficking pathways. The N-terminus of Tuba binds dynamin1, and the C-terminus contains domains that can interact with signaling pathways and cytoskeletal regulatory elements. We investigated Tuba localization, distribution and function in B16 melanoma cells. Tuba overexpression stimulated dorsal ruffles that occurred independently of dynamin function. Tuba expression induced actin-driven motility of small puncta that required the C-terminal SH3, GEF and BAR domains. Additionally, Tuba was recruited to lipid vesicles generated by overexpression of phosphatidylinositol-4-phosphate 5-kinase type Iα (PIP5Kα), localizing prominently to the head of the comets and at lower levels along the actin tail. We propose that Tuba facilitates dorsal ruffling of melanoma cells through direct interaction with actin-regulatory proteins and the recruitment of signaling molecules to lipid microdomains for the coordinated assembly of a cytoskeletal network. Knockdown of Tuba by RNA interference (RNAi) attenuated PIP5Kα-generated comet formation and the invasive behavior of B16 cells, implying that Tuba function is required for certain aspects of these processes. These results suggest first that Tuba-stimulated dorsal ruffling might represent a novel mechanism for the coordination of N-WASP-dependent cytoskeletal rearrangements and second that Tuba function is implicated in motility processes.

Clonal chromosome abnormalities in 54 cases of ovarian carcinoma

As a prelude to assessing the relationship of chromosome alterations to clinical outcome in ovarian carcinoma, we report on the cytogenetic analysis on short-term cultures from 54 patients. All patients had histopathologically confirmed malignancy, with the majority of cases demonstrating serous ovarian adenocarcinomas. Structural alterations were evident in 52 cases, whereas numeric changes were identified in 13 cases. The most notable numeric abnormalities were loss of the X-chromosome (9/13 total cases) and +7 (3/9 diploid cases). Structural alterations most frequently involved chromosomes 1, 3, 6, 7, 11, and 12. Chromosomal breakpoints were shown to cluster in several chromosomal banding regions, including 1p36, 1p11-q21, 3p23-p10, 7p (especially 7p22), 11p, 11q, 12p13-q12, and 12q24. The frequency of structural alterations involving the following chromosome arms was found to be significantly increased: 1p (p < 0.01), 7p (p < 0.01), 11p (p < 0.01), 11q (p < 0.05), and 12p (p < 0.05). An analysis of the net gain or loss of chromosome segments was also performed, with the most consistent tendency observed being over-representation of 1q and chromosome 7, deletion of 1p, and loss of the X chromosome.

Extracellular signal-regulated kinases in T cells: Characterization of human ERK1 and ERK2 cDNAs☆☆☆

Extracellular signal-regulated kinases 1 and 2 are growth factor-sensitive serine/threonine kinases. cDNAs for both human kinases were isolated and sequenced. The nucleic acid and deduced protein sequences of human extracellular signal-regulated kinase 1 were 88% and 96% identical, respectively, to the homologous rat sequences. The nucleic acid and deduced protein sequences of human extracellular signal-regulated kinase 2 were 90% and 98% identical, respectively, to the corresponding rat sequences. A human extracellular signal-regulated kinase 2 specific probe was used to demonstrate that the mRNA for this kinase was present in T cells and did not change with activation. The deduced protein sequences of both human kinases were greater than 95% identical to two Xenopus kinase sequences, indicating that these enzymes are highly conserved across species.

A touch of TRALI.

Transfusion‐related acute lung injury (TRALI) is a leading cause of transfusion‐associated morbidity and mortality. The National Heart, Lung, and Blood Institute (NHLBI) and Canadian Consensus Conference definitions of TRALI exclude cases of mild TRALI. As a result, many cases of mild TRALI are likely to be missed. Three cases are reported in which patients experienced the acute onset of breathlessness in association with transfusion of blood components containing human leukocyte antigen (HLA) antibodies reactive with recipient HLA antigens. Despite the sudden onset of a pulmonary syndrome in association with transfusion, clinicians caring for these patients did not consider TRALI, and no case would meet recent consensus definitions. Nevertheless, supporting clinical and serologic evidence for TRALI was found in each case. Benefits in recognizing mild cases of TRALI include quantifying the true incidence of TRALI, understanding the physiology of mild versus severe TRALI, and preventing subsequent cases of TRALI due to donors found to have HLA antibodies.

ADAMTS13 binds to CD36: a potential mechanism for platelet and endothelial localization of ADAMTS13

BACKGROUND: ADAMTS13 cleaves ultralarge von Willebrand factor (VWF) and plays a significant role in vascular biology and thrombotic thrombocytopenic purpura. CD36, a transmembrane protein present on endothelial cells and platelets (PLTs), binds to thrombospondin via three thrombospondin type 1 repeats. ADAMTS13 contains eight thrombospondin type 1 repeats.

The evaluation of infertility.

Infertility is a significant medical problem that affects many couples. Evaluation is the starting point for treatment of infertility as it may suggest specific causes and appropriate treatment modalities. Although the history and physical examination provide important information, specific diagnostic tests are required to evaluate infertility. Because the causes of infertility can be multifactorial, a systematic approach typically is used and involves testing for male factor, ovulatory factor, uterotubal factor, and peritoneal factor. Many of these diagnostic tests are laboratory based, including semen analysis, serum progesterone level, serum basal follicle-stimulating hormone level, and clomiphene citrate challenge, and can be done by the primary care physician. Moreover, by understanding the infertility evaluation, the primary care physician can serve as an important resource for advice about infertility. This article briefly reviews the diagnostic approach to infertility, with particular emphasis on important laboratory tests used for evaluation.

Detection of fetomaternal hemorrhage

The prevention of Rhesus D alloimmunization through Rh immune globulin (RhIg) administration is the major indication for the accurate detection and quantification of fetomaternal hemorrhage (FMH). In the setting of D incompatibility, D‐positive fetal cells can sensitize the D‐negative mother, resulting in maternal anti‐D alloantibody production. These anti‐D alloantibodies may lead to undesirable sequelae such as hemolytic disease of the newborn (HDN). Since the widespread adoption of FMH screening and RhIg immunoprophylaxis, the overall risk of Rh alloimmunization and infant mortality from HDN has substantially decreased. The rosette screen, the initial test of choice, is highly sensitive in qualitatively detecting 10 mL of fetal whole blood in the maternal circulation. As the screen is reliant on the presence of the D antigen to distinguish fetal from maternal cells, it cannot be used to detect FMH in D‐positive mothers or in D‐negative mothers carrying a D‐negative fetus. The Kleihauer‐Betke acid‐elution test, the most widely used confirmatory test for quantifying FMH, relies on the principle that fetal RBCs contain mostly fetal hemoglobin (HbF), which is resistant to acid‐elution whereas adult hemoglobin is acid‐sensitive. Although the Kleihauer‐Betke test is inexpensive and requires no special equipment, it lacks standardization and precision, and may not be accurate in conditions with elevated F‐cells. Anti‐HbF flow cytometry is a promising alternative, although its use is limited by equipment and staffing costs. Hematology analyzers with flow cytometry capabilities may be adapted for fetal cell detection, thus giving clinical laboratories a potentially attractive automated alternative for quantifying FMH. Am. J. Hematol., 2012.

Successful Delayed Secondary Open Conversion After Endovascular Repair Using Partial Explantation Technique: A Single-Center Experience

BACKGROUND Endovascular aneurysm repair (EVAR) reduces the morbidity and mortality associated with abdominal aortic aneurysm repair, but in some patients endoleak or aneurysm expansion may necessitate secondary open conversion (SOC). We reviewed the outcomes after delayed SOC following EVAR in consecutive patients at a single center. METHODS We retrospectively reviewed all patients undergoing EVAR to identify a cohort undergoing delayed SOC in a single center between 1998 and 2008. We analyzed delayed SOC patients for operative indications, technique, and early outcomes. We made specific comment on the surgical techniques used, with respect to partial or total endograft explantation. RESULTS Delayed SOC was carried out in 10/285 (3.5%) consecutive patients implanted with the Zenith endograft; during this period, two further patients had SOC after initial EVAR in another center. Graft types were Zenith (n = 10), Talent (n = 1), and AneuRx (n = 1). Indications for open conversion were infected graft (n = 3), sac expansion (n = 3), type 1 endoleak (n = 2), type 2 endoleak (n = 2), juxtarenal aneurysm (n = 1), and rupture (n = 1). Explantation techniques were partial explantation with in situ replacement (n = 7), full explantation with axillobifemoral bypass (n = 3), in situ replacement (n = 1), and suturing (n = 1)Complete stent explantation was required in 4 patients with axillo-bifemoral bypass in three of them. 7 patients had partial stent explantation and one patient stent was left insitu. Postoperative morbidities included myocardial infarction (n = 1), renal dialysis (n = 1), and chest infection (n = 3). No 30-day mortality was noted, and all patients were discharged from hospital and remain well with median follow-up of 5 months (interquartile range 1.7-26.7). CONCLUSION SOC after EVAR is feasible in selected patients with low morbidity and mortality. Partial explantation with in situ replacement, in the absence of sepsis, may be the preferred revascularization option but may require long-term follow-up.

Derivation and external validation of the PLASMIC score for rapid assessment of adults with thrombotic microangiopathies: a cohort study

BACKGROUND Among the syndromes characterised by thrombotic microangiopathy, thrombotic thrombocytopenic purpura is distinguished by a severe deficiency in the ADAMTS13 enzyme. Patients with this disorder need urgent treatment with plasma exchange. Because ADAMTS13 activity testing typically requires prolonged turnaround times and might be unavailable in resource-poor settings, a method to rapidly assess the likelihood of severe ADAMTS13 deficiency is needed. METHODS All consecutive adult patients presenting to three large academic medical centres in Boston, MA, USA, with thrombotic microangiopathy and a possible diagnosis of thrombotic thrombocytopenic purpura between Jan 8, 2004, and Dec 6, 2015, were included in an ongoing multi-institutional registry (the Harvard TMA Research Collaborative). Univariate analysis was used to identify covariates for a logistic regression model predictive of severe ADAMTS13 deficiency (≤10% activity). A clinical point score was generated, and its diagnostic performance was assessed using internal and external validation cohorts and compared to clinical assessment alone. FINDINGS 214 patients with thrombotic microangiopathy were included in the derivation cohort. A seven-component clinical prediction tool, termed the PLASMIC score, was developed and found to reliably assess the pretest probability of severe ADAMTS13 deficiency (C statistic 0·96, 95% CI 0·92-0·98). Our diagnostic model was reproducibly accurate in both the internal (0·95, 0·91-0·98) and external (0·91, 0·85-0·95) validation cohorts. The scoring system also more consistently diagnosed thrombotic microangiopathy due to severe ADAMTS13 deficiency than did standard clinical assessment, as measured by C statistic (0·96, 95% CI 0·92-0·98 for PLASMIC vs 0·83, 0·77-0·88 for clinical assessment; p<0·0001) and mean Brier score (0·065 for PLASMIC vs 0·111 for clinical assessment; mean paired difference 0·05, 95% CI 0·01-0·08; p<0·0001). When utilised in addition to clinical assessment, the PLASMIC score contributed significant discriminatory power (integrated discrimination improvement 0·24, 95% CI 0·11-0·37). INTERPRETATION We have developed and validated a clinical prediction tool-the PLASMIC score-to stratify patients with thrombotic microangiopathy according to their risk of having severe ADAMTS13 deficiency. We have shown that this scoring system is superior to standard clinical assessment in addressing the diagnostic challenge presented by thrombotic microangiopathy. Its use, together with clinical judgment, may facilitate treatment decisions in patients for whom timely results of ADAMTS13 activity testing are unavailable. FUNDING The Luick Family Fund of Massachusetts General Hospital.