ERbeta1 and the ERbeta2 splice variant (ERbetacx/beta2) are expressed in distinct cell populations in the adult human testis

Estrogens can regulate germ cell function. Estrogen action is mediated via high affinity ERs; two subtypes (ERalpha and ERbeta) have been identified. We have shown previously that ERbeta is expressed in nuclei of multiple human testicular cells. A variant isoform of human (h) ERbeta (hERbetacx/2), formed by alternative splicing, has been identified in testicular cDNA libraries by two laboratories. The present study examined the expression of wild-type (ERbeta1) and variant (ERbeta2) beta receptors in human testes by 1) RT-PCR with isoform specific primers, and 2) single and double immunohistochemistry using monoclonal antibodies raised against peptides unique to the C termini of hERbeta1 and hERbeta2. PCR products specific for ERbeta1 and ERbeta2 were amplified from cDNA pools prepared from human testes and granulosa cells. On Western blots, the anti-ERbeta1 monoclonal antibody bound to recombinant ERbeta1 and the anti-ERbeta2 monoclonal to recombinant hERbeta2. Neither bound to the other ERbeta isoform nor to recombinant ERalpha. ERbeta1 and ERbeta2 proteins were both detected in human testis. Immunoexpression of ERbeta1 was most intense in pachytene spermatocytes and round spermatids, whereas low levels of expression were detected in Sertoli cells, spermatogonia, preleptotene, leptotene, zygotene, and diplotene spermatocytes. Highest levels of expression of ERbeta2 protein were detected in Sertoli cells and spermatogonia with low/variable expression in preleptotene, pachytene, and diplotene spermatocytes. No immunostaining was detected in elongating spermatids. Most interstitial cells expressed more ERbeta2 than ERbeta1. It is speculated that the cells most susceptible to modulation by estrogenic ligands are round spermatids in which levels of expression of ERbeta1 are high. In contrast, expression of ERbeta2, an isoform that may act as a dominant negative inhibitor of ER action, in Sertoli cells and spermatogonia, could protect these cells from adverse effects of estrogens.     

Human capillary morphogenesis protein 2 functions as an anthrax toxin receptor

Bacillus anthracis secretes two bipartite toxins thought to be involved in anthrax pathogenesis and resulting death of the host. The current model for intoxication is that protective antigen (PA) toxin subunits bind a single group of cell-surface anthrax toxin receptors (ATRs), encoded by the tumor endothelial marker 8 (TEM8) gene. The ATR/TEM8-PA interaction is mediated by the receptor's extracellular domain related to von Willebrand factor type A or integrin inserted domains (VWA/I domains). A metal ion-dependent adhesion site (MIDAS) located within this domain of the ATR/TEM8 protein chelates a divalent cation critical for PA binding. In this report, we identify a second PA receptor encoded by capillary morphogenesis gene 2 (CMG2), which has 60% amino acid identity to ATR/TEM8 within the VWA/I domain, as well as a conserved MIDAS motif. A recombinant CMG2 protein bound PA and mediated toxin internalization when expressed on receptor-deficient cells. Binding between the CMG2 VWA/I domain and PA was shown to be direct and metal-dependent, although the cation specificity of this interaction is different than that observed with ATR/TEM8. Northern blot analysis revealed that CMG2 is widely expressed in human tissues, indicating that this receptor is likely to be relevant for disease pathogenesis. Finally, a soluble version of the CMG2 VWA/I domain inhibited intoxication of cells expressing endogenous toxin receptors when it was added to PA at a 3:1 ratio. These studies distinguish CMG2 as a second anthrax toxin receptor and identify a potent antitoxin that may prove useful for the treatment of anthrax.     

Liposomal delivery of methylphosphonate antisense oligodeoxynucleotides in chronic myelogenous leukemia [see comments]

Chronic myelogenous leukemia (CML) is a hematologic malignancy characterized by the presence of the Philadelphia (Ph) chromosome. Bcr- abl, the fusion gene associated with the Ph chromosome, expresses a p210bcr-abl protein that promotes a selective expansion of mature myeloid progenitor cells. Methylphosphonate (MP) oligodeoxynucleotides complementary to specific regions of the bcr-abl mRNA were incorporated in liposomes. We studied the effects of liposomal MP (L-MP) on the growth inhibition of CML-like cell lines. L-MP targeted to the breakpoint junctions of the bcr-abl mRNA inhibited the growth of CML cells. Fifty percent inhibition was achieved at approximately 1 mumol/L of L-MP oligonucleotide concentrations. The inhibitory effect was selective because growth inhibition was observed only with CML but not with control cell lines. Moreover, CML cell growth inhibition was dependent on the sequence of the MP oligodeoxynucleotides incorporated in the liposomes. The growth inhibition of CML cells by L-MP resulted from selective inhibition of the expression of the p210bcr-abl protein.     

Rationing Limited Healthcare Resources in the COVID-19 Era and Beyond: Ethical Considerations Regarding Older Adults

Coronavirus disease 2019 (COVID-19) continues to impact older adults disproportionately with respect to serious consequences ranging from severe illness and hospitalization to increased mortality risk. Concurrently, concerns about potential shortages of healthcare professionals and health supplies to address these issues have focused attention on how these resources are ultimately allocated and used. Some strategies, for example, misguidedly use age as an arbitrary criterion that disfavors older adults in resource allocation decisions. This is a companion article to the American Geriatrics Society (AGS) position statement, “Resource Allocation Strategies and Age-Related Considerations in the COVID-19 Era and Beyond.” It is intended to inform stakeholders including hospitals, health systems, and policymakers about ethical considerations that should be considered when developing strategies for allocation of scarce resources during an emergency involving older adults. This review presents the legal and ethical background for the position statement and discusses these issues that informed the development of the AGS positions: (1) age as a determining factor, (2) age as a tiebreaker, (3) criteria with a differential impact on older adults, (4) individual choices and advance directives, (5) racial/ethnic disparities and resource allocation, and (6) scoring systems and their impact on older adults. It also considers the role of advance directives as expressions of individual preferences in pandemics. J Am Geriatr Soc 68:1143–1149, 2020.     

Missing canines: a novel aetiology

Infant oral mutilation is the practice of removing developing tooth germs, commonly the mandibular canine, in infants up to the age of 1 year. Subsequent complications include missing, impacted or hypoplastic permanent anterior and canine teeth. We report on a case of bilaterally missing lower canines thought to be due to infant oral mutilation. It is important that general dental practitioners are aware of this practice and resulting complications when treating families from sub‐Saharan East Africa.     

Unusual serological response to hepatitis E virus in plasma donors consistent with re‐infection

Hepatitis E virus (HEV)‐positive plasma donations, identified by a plasma mini‐pool screening approach, were analysed using serological methods for the presence of anti‐HEV IgM and IgG. Avidity testing was performed on the IgG‐reactive donations. Anti‐HEV IgG with high avidity was observed in two donors together with high viral loads, but with the absence of anti‐HEV IgM. These data are suggestive of re‐infection in a small proportion of plasma donors, which has not previously been reported.     

Multicenter prospective study of nonruptured abdominal aortic aneurysms. I. Population and operative management

This article describes the patient population and operative management of 666 patients with nonruptured aneurysms of the abdominal aorta. Statistical significance of variables was determined by the chi-square test and logistic regression analysis. There were no statistically significant differences (p greater than 0.05) in mortality rate for abdominal aortic aneurysm (AAA) on the basis of indication for surgery (asymptomatic, 3.9%; asymptomatic but with evidence of enlargement, 4.9%; and symptomatic, 7.2%) or the urgency of operation (elective operation, 4.5%; and urgent operation, 7.1%). Characteristics of the 72 participating surgeons did not influence the operative mortality rate. A family history of AAA was documented in 6.1% of cases and was more common if the patient was female (p = 0.03) and less than 65 years of age (p = 0.04). Patients without clinical evidence of coronary artery disease had a 0.8% mortality rate from cardiac disease compared with 6.2% if any stigmata of coronary disease were present. Prior aortocoronary bypass surgery did not reduce the incidence of postoperative cardiac events or operative mortality rate. Patients having "routine" angiography did not have a less complicated operative course, fewer thrombotic complications, or lower mortality rate than those not having it. Those patients with an inflammatory AAA (4.5%) did not have a significantly higher incidence of pain. Heparin administration (84.8%) did not reduce the complications of graft thrombosis, "trash," distal thrombosis, and/or amputation. The 6.8% of patients requiring suprarenal aortic cross-clamping had a higher incidence of postoperative renal dysfunction (p = 0.02) and intraoperative blood loss (p less than 0.001), but cardiac events were not more frequent. When the aortic cross-clamping time was prolonged (more than 70 minutes), the requirement for crystalloid fluid administration increased (p less than 0.001) and postoperative myocardial infarction was more common (p = 0.004). After ligation of the left renal vein in 7.9%, renal damage or dialysis was more frequent (p = 0.01). Patients having an intra-abdominal graft (tube, 38.5% and biiliac, 30.7%) had fewer wound infections (p = 0.02) and graft thromboses (p less than 0.001) than the patients with a femoral anastomosis. When the internal iliac artery flow was interrupted bilaterally (12%), diarrhea (p = 0.03) and ischemic colitis (p = 0.03) were more frequent complications. Reimplantation of the inferior mesenteric artery was carried out in 4.8%. After renal artery bypass in 2.1%, the mortality rate was not increased, but the incidence of transient renal dysfunction was increased (p = 0.03).(ABSTRACT TRUNCATED AT 400 WORDS)     

Use of a radioimmunoassay to quantify thrombospondin

Results of radioimmunoassay procedures applied to samples containing thrombospondin indicated that reliable values are obtained either in saline or in plasma. Plasma levels in apparently normal individuals ranged from approximately 20 to 300 ng/ml. The mean for 20 individuals was 175 ng/ml. Plasma specimens stored either refrigerated at 4 degrees C or frozen at -80 degrees C showed significantly diminished thrombospondin levels over a period of 90 days. Serum levels of thrombospondin were found to range from 10,000 to 30,000 ng/ml.