In vitro and in vivo persistence of reticulocytes from donor red cells

BACKGROUND: Reticulocytes are important in the phenotyping of transfused patients. Reticulocytes can persist in blood units for the shelf life of the unit. STUDY DESIGN AND METHODS: Temperature dependence of reticulocyte persistence was examined in vitro at 4, 24, and 37 degrees C by using thiazole orange staining and flow cytometric analysis. Two-color flow cytometric analysis was used to evaluate the persistence of donor reticulocytes in transfused patients. RESULTS: Flow cytometric analysis using thiazole orange demonstrated that persistence of reticulocytes in units of stored CPDA-1 blood was temperature-dependent. Reticulocytes disappeared over 13 and 6 days at 24 degrees C and 37 degrees C, respectively, but at 4 degrees C the reticulocyte count changed little over 35 days. Two-color flow cytometric analysis of reticulocyte antigens was used to follow donor reticulocytes in 14 transfusion events in nine different patients. Donor reticulocytes persisted through 24 hours in 75 percent of the patients and were detectable at 48 hours in three patients. CONCLUSION: This study demonstrates that reticulocytes persist during refrigerated storage; they are detectable in the circulation of most recipients for the first 24 hours after transfusion and in the circulation of a few recipients after 48 hours. These findings may have relevance for separation techniques based on reticulocyte density in samples drawn shortly after transfusion and for evaluation of reticulocyte counts in patients with hematologic abnormalities.     

Mutations in Known Monogenic High Bone Mass Loci Only Explain a Small Proportion of High Bone Mass Cases

High bone mass (HBM) can be an incidental clinical finding; however, monogenic HBM disorders (eg, LRP5 or SOST mutations) are rare. We aimed to determine to what extent HBM is explained by mutations in known HBM genes. A total of 258 unrelated HBM cases were identified from a review of 335,115 DXA scans from 13 UK centers. Cases were assessed clinically and underwent sequencing of known anabolic HBM loci: LRP5 (exons 2, 3, 4), LRP4 (exons 25, 26), SOST (exons 1, 2, and the van Buchem's disease [VBD] 52‐kb intronic deletion 3′). Family members were assessed for HBM segregation with identified variants. Three‐dimensional protein models were constructed for identified variants. Two novel missense LRP5 HBM mutations ([c.518C>T; p.Thr173Met], [c.796C>T; p.Arg266Cys]) were identified, plus three previously reported missense LRP5 mutations ([c.593A>G; p.Asn198Ser], [c.724G>A; p.Ala242Thr], [c.266A>G; p.Gln89Arg]), associated with HBM in 11 adults from seven families. Individuals with LRP5 HBM (～prevalence 5/100,000) displayed a variable phenotype of skeletal dysplasia with increased trabecular BMD and cortical thickness on HRpQCT, and gynoid fat mass accumulation on DXA, compared with both non‐LRP5 HBM and controls. One mostly asymptomatic woman carried a novel heterozygous nonsense SOST mutation (c.530C>A; p.Ser177X) predicted to prematurely truncate sclerostin. Protein modeling suggests the severity of the LRP5‐HBM phenotype corresponds to the degree of protein disruption and the consequent effect on SOST‐LRP5 binding. We predict p.Asn198Ser and p.Ala242Thr directly disrupt SOST binding; both correspond to severe HBM phenotypes (BMD Z‐scores +3.1 to +12.2, inability to float). Less disruptive structural alterations predicted from p.Arg266Cys, p.Thr173Met, and p.Gln89Arg were associated with less severe phenotypes (Z‐scores +2.4 to +6.2, ability to float). In conclusion, although mutations in known HBM loci may be asymptomatic, they only account for a very small proportion (～3%) of HBM individuals, suggesting the great majority are explained by either unknown monogenic causes or polygenic inheritance. © 2015 The Authors Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).     

Adolescent adjustment in the context of life change: The supportive role of parental structure provision

This study examined the associations among disruptive life events, supportive parenting practices, adolescent self-perceptions, and emotional outcomes. One-hundred and three 7th graders (68% minority, 32% European American) and their parents completed recent negative life events checklists. Parents also reported the total number of major transitions (changes in residences, schools, parent's romantic partners) that adolescents experienced since birth. Life events were related to lower adolescent-reported perceptions of competence and control, higher adolescent-reported depression and behavior problems, and higher parent-reported conduct problems. Regression analyses supported a mediational model in which competence and control perceptions explained relations between adolescent life events and symptomatology. Parental structure—the provision of clear, consistent and predictable rules and expectations—was associated with more adaptive adolescent functioning, especially among girls. Regressions indicated that structure related to higher perceptions of competence and control and fewer behavioral problems, even after accounting for the risk associated with negative life events and transitions.     

Eradication of minimal disease in severe combined immunodeficient mice with disseminated Daudi lymphoma using chemotherapy and an immunotoxin cocktail

Severe combined immunodeficient (SCID) mice injected intravenously with a human Burkitt's lymphoma cell line (Daudi) develop disseminated lymphoma (SCID/Daudi), which is fatal in 100% of the mice. Early treatment of these mice with either an immunotoxin (IT) cocktail (consisting of anti-CD19-ricin A chain plus anti-CD22-ricin A chain) or chemotherapy significantly prolonged survival but was not curative. Combination therapy with the IT cocktail and any one of three chemotherapeutic drugs (doxorubicin, cytoxan, or camptothecin) cured the mice. Cure was demonstrated by both histopathologic examination of treated mice and, more importantly, by adoptive transfer of cells from organs of the cured mice to naive SCID mice where 100 tumor cells would have caused disease in the recipients. These results provide a strong rationale for combining IT therapy with conventional chemotherapy in the treatment of B-cell neoplasia.     

Molecular typing of Helicobacter pylori isolates from a multicenter U.S. clinical trial by ureC restriction fragment length polymorphism.

The molecular typing of 81 pretreatment Helicobacter pylori isolates and the comparison of 18 pretreatment-posttreatment pairs is described by restriction fragment length polymorphism (RFLP) of the ureC gene. The results of our study show the extreme genomic diversity of H. pylori and indicate that infection by H. pylori in the United States does not appear to be limited to a small number of RFLP types.     

Expression of stratified epithelial-type cytokeratins in hyalinizing trabecular adenomas supports their relationship with papillary carcinomas of the thyroid

 

Aim:

To evaluate the cytokeratin pattern of expression of hyalinizing trabecular adenomas and to verify whether or not these tumours, that share morphological features with papillary carcinomas, present the stratified epithelial-type cytokeratins commonly found in ordinary papillary carcinomas.  

Methods and results:

This study consisted of the immunohistochemical detection of simple and stratified epithelial type cytokeratin filaments in a series of six hyalinizing trabecular adenomas, three papillary carcinomas with a trabecular growth pattern and two carcinomas combining hyalinizing trabecular and papillary patterns. Simple epithelial-type cytokeratins 7, 8, 18 and 19 were found in every case. Expression of the stratified epithelial-type cytokeratins 1, 5/6 and/or 13 was detected in four hyalinizing trabecular adenomas.  

Conclusion:

Based on this, as well as on the cytological features and on the frequent co-occurrence of hyalinizing trabecular adenoma and papillary carcinoma, we suggest that the former lesion may be considered a peculiar encapsulated variant of papillary carcinoma.