SALL4 Expression in Gonocytes and Spermatogonial Clones of Postnatal Mouse Testes

The spermatogenic lineage is established after birth when gonocytes migrate to the basement membrane of seminiferous tubules and give rise to spermatogonial stem cells (SSC). In adults, SSCs reside within the population of undifferentiated spermatogonia (Aundiff) that expands clonally from single cells (Asingle) to form pairs (Apaired) and chains of 4, 8 and 16 Aaligned spermatogonia. Although stem cell activity is thought to reside in the population of Asingle spermatogonia, new research suggests that clone size alone does not define the stem cell pool. The mechanisms that regulate self-renewal and differentiation fate decisions are poorly understood due to limited availability of experimental tools that distinguish the products of those fate decisions. The pluripotency factor SALL4 (sal-like protein 4) is implicated in stem cell maintenance and patterning in many organs during embryonic development, but expression becomes restricted to the gonads after birth. We analyzed the expression of SALL4 in the mouse testis during the first weeks after birth and in adult seminiferous tubules. In newborn mice, the isoform SALL4B is expressed in quiescent gonocytes at postnatal day 0 (PND0) and SALL4A is upregulated at PND7 when gonocytes have colonized the basement membrane and given rise to spermatogonia. During steady-state spermatogenesis in adult testes, SALL4 expression overlapped substantially with PLZF and LIN28 in Asingle, Apaired and Aaligned spermatogonia and therefore appears to be a marker of undifferentiated spermatogonia in mice. In contrast, co-expression of SALL4 with GFRα1 and cKIT identified distinct subpopulations of Aundiff in all clone sizes that might provide clues about SSC regulation. Collectively, these results indicate that 1) SALL4 isoforms are differentially expressed at the initiation of spermatogenesis, 2) SALL4 is expressed in undifferentiated spermatogonia in adult testes and 3) SALL4 co-staining with GFRα1 and cKIT reveals distinct subpopulations of Aundiff spermatogonia that merit further investigation. © 2013 Gassei, Orwig

Are Ethnic and Gender Specific Equations Needed to Derive Fat Free Mass from Bioelectrical Impedance in Children of South Asian, Black African-Caribbean and White European Origin? Results of the Assessment of Body Composition in Children Study

Background Bioelectrical impedance analysis (BIA) is a potentially valuable method for assessing lean mass and body fat levels in children from different ethnic groups. We examined the need for ethnic- and gender-specific equations for estimating fat free mass (FFM) from BIA in children from different ethnic groups and examined their effects on the assessment of ethnic differences in body fat. Methods Cross-sectional study of children aged 8–10 years in London Primary schools including 325 South Asians, 250 black African-Caribbeans and 289 white Europeans with measurements of height, weight and arm-leg impedance (Z; Bodystat 1500). Total body water was estimated from deuterium dilution and converted to FFM. Multilevel models were used to derive three types of equation {A: FFM = linear combination(height+weight+Z); B: FFM = linear combination(height2/Z); C: FFM = linear combination(height2/Z+weight)}. Results Ethnicity and gender were important predictors of FFM and improved model fit in all equations. The models of best fit were ethnicity and gender specific versions of equation A, followed by equation C; these provided accurate assessments of ethnic differences in FFM and FM. In contrast, the use of generic equations led to underestimation of both the negative South Asian-white European FFM difference and the positive black African-Caribbean-white European FFM difference (by 0.53 kg and by 0.73 kg respectively for equation A). The use of generic equations underestimated the positive South Asian-white European difference in fat mass (FM) and overestimated the positive black African-Caribbean-white European difference in FM (by 4.7% and 10.1% respectively for equation A). Consistent results were observed when the equations were applied to a large external data set. Conclusions Ethnic- and gender-specific equations for predicting FFM from BIA provide better estimates of ethnic differences in FFM and FM in children, while generic equations can misrepresent these ethnic differences

Prediction of adverse maternal outcomes in pre-eclampsia: development and validation of the fullPIERS model.

BACKGROUND: Pre-eclampsia is a leading cause of maternal deaths. These deaths mainly result from eclampsia, uncontrolled hypertension, or systemic inflammation. We developed and validated the fullPIERS model with the aim of identifying the risk of fatal or life-threatening complications in women with pre-eclampsia within 48 h of hospital admission for the disorder. METHODS: We developed and internally validated the fullPIERS model in a prospective, multicentre study in women who were admitted to tertiary obstetric centres with pre-eclampsia or who developed pre-eclampsia after admission. The outcome of interest was maternal mortality or other serious complications of pre-eclampsia. Routinely reported and informative variables were included in a stepwise backward elimination regression model to predict the adverse maternal outcome. We assessed performance using the area under the curve (AUC) of the receiver operating characteristic (ROC). Standard bootstrapping techniques were used to assess potential overfitting. FINDINGS: 261 of 2023 women with pre-eclampsia had adverse outcomes at any time after hospital admission (106 [5%] within 48 h of admission). Predictors of adverse maternal outcome included gestational age, chest pain or dyspnoea, oxygen saturation, platelet count, and creatinine and aspartate transaminase concentrations. The fullPIERS model predicted adverse maternal outcomes within 48 h of study eligibility (AUC ROC 0·88, 95% CI 0·84-0·92). There was no significant overfitting. fullPIERS performed well (AUC ROC >0·7) up to 7 days after eligibility. INTERPRETATION: The fullPIERS model identifies women at increased risk of adverse outcomes up to 7 days before complications arise and can thereby modify direct patient care (eg, timing of delivery, place of care), improve the design of clinical trials, and inform biomedical investigations related to pre-eclampsia. FUNDING: Canadian Institutes of Health Research; UNDP/UNFPA/WHO/World Bank Special Programme of Research, Development, and Research Training in Human Reproduction; Preeclampsia Foundation; International Federation of Obstetricians and Gynecologists; Michael Smith Foundation for Health Research; and Child and Family Research Institute

Citrullination of histone H3 drives IL-6 production by bone marrow mesenchymal stem cells in MGUS and multiple myeloma

Multiple myeloma (MM), an incurable plasma cell malignancy, requires localisation within the bone marrow. This microenvironment facilitates crucial interactions between the cancer cells and stromal cell types that permit the tumour to survival and proliferate. There is increasing evidence that the bone marrow mesenchymal stem cell (BMMSC) is stably altered in patients with MM – a phenotype also postulated to exist in patients with monoclonal gammopathy of undetermined significance (MGUS) a benign condition that precedes MM. In this study, we describe a mechanism by which increased expression of peptidyl arginine deiminase 2 (PADI2) by BMMSCs in patients with MGUS and MM directly alters malignant plasma cell phenotype. We identify PADI2 as one of the most highly upregulated transcripts in BMMSCs from both MGUS and MM patients, and that through its enzymatic deimination of histone H3 arginine 26, PADI2 activity directly induces the upregulation of interleukin-6 (IL-6) expression. This leads to the acquisition of resistance to the chemotherapeutic agent, bortezomib, by malignant plasma cells. We therefore describe a novel mechanism by which BMMSC dysfunction in patients with MGUS and MM directly leads to pro-malignancy signalling through the citrullination of histone H3R26

Metabolic Syndrome and Cardiovascular Disease after Hematopoietic Cell Transplantation: Screening and Preventive Practice Recommendations from the CIBMTR and EBMT

Metabolic syndrome (MetS) is a constellation of cardiovascular risk factors that increases the risk of cardiovascular disease, diabetes mellitus, and all-cause mortality. Long-term survivors of hematopoietic cell transplantation (HCT) have a substantial risk of developing MetS and cardiovascular disease, with an estimated prevalence of MetS of 31% to 49% among HCT recipients. Although MetS has not yet been proven to impact cardiovascular risk after HCT, an understanding of the incidence and risk factors for MetS in HCT recipients can provide the foundation to evaluate screening guidelines and develop interventions that may mitigate cardiovascular-related mortality. A working group was established through the Center for International Blood and Marrow Transplant Research and the European Group for Blood and Marrow Transplantation with the goal to review literature and recommend practices appropriate to HCT recipients. Here we deliver consensus recommendations to help clinicians provide screening and preventive care for MetS and cardiovascular disease among HCT recipients. All HCT survivors should be advised of the risks of MetS and encouraged to undergo recommended screening based on their predisposition and ongoing risk factors

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Transplacental Transmission of Leishmania infantum as a Means for Continued Disease Incidence in North America

Dogs are a favored feeding source for sand flies that transmit human L. infantum infection. Zoonotic visceral leishmaniasis (ZVL) is an emerging problem in some U.S. dog breeds, with over 20% of at-risk Foxhounds infected. Although classically Leishmania is transmitted by infected sand flies which exist in the United States, no role has yet been determined for vector-borne transmission. Means of ongoing L. infantum transmission in U.S. dogs is unknown. Possibilities include transplacental and horizontal/venereal transmission. Aims for this study were to establish whether transplacental transmission occurred in Leishmania-infected U.S. dogs and determine the effect of this transmission on immune recognition of Leishmania. This novel report describes wide-spread infection as identified by kqPCR in 8 day-old pups born to a naturally-infected, seropositive U.S. dog with no travel history. This is the first report of transplacental transmission of L. infantum in naturally-infected dogs in North America. Evidence that mom-to-pup transmission of ZVL may continue disease in an otherwise non-endemic region has significant implications on current control strategies for ZVL. Determining frequency of vertical transmission and incorporating canine sterilization with vector control may have a more significant impact on ZVL transmission to people in endemic areas than current control efforts

Polymer ultrapermeability from the inefficient packing of 2D chains

The promise of ultrapermeable polymers, such as poly(trimethylsilylpropyne) (PTMSP), for reducing the size and increasing the efficiency of membranes for gas separations remains unfulfilled due to their poor selectivity. We report an ultrapermeable polymer of intrinsic microporosity (PIM-TMN-Trip) that is substantially more selective than PTMSP. From molecular simulations and experimental measurement we find that the inefficient packing of the two-dimensional (2D) chains of PIM-TMN-Trip generates a high concentration of both small (<0.7 nm) and large (0.7–1.0 nm) micropores, the former enhancing selectivity and the latter permeability. Gas permeability data for PIM-TMN-Trip surpass the 2008 Robeson upper bounds for O2/N2, H2/N2, CO2/N2, H2/CH4 and CO2/CH4, with the potential for biogas purification and carbon capture demonstrated for relevant gas mixtures. Comparisons between PIM-TMN-Trip and structurally similar polymers with three-dimensional (3D) contorted chains confirm that its additional intrinsic microporosity is generated from the awkward packing of its 2D polymer chains in a 3D amorphous solid. This strategy of shape-directed packing of chains of microporous polymers may be applied to other rigid polymers for gas separations

A 6-week, multicentre, randomised, double-blind, double-dummy, active-controlled, clinical safety study of lumiracoxib and rofecoxib in osteoarthritis patients

<p>Abstract</p> <p>Background</p> <p>Lumiracoxib is a selective cyclooxygenase-2 inhibitor effective in the treatment of osteoarthritis (OA) with a superior gastrointestinal (GI) safety profile as compared to traditional non-steroidal anti-inflammatory drugs (NSAIDs, ibuprofen and naproxen). This safety study compared the GI tolerability, the blood pressure (BP) profile and the incidence of oedema with lumiracoxib and rofecoxib in the treatment of OA. Rofecoxib was withdrawn worldwide due to an associated increased risk of CV events and lumiracoxib has been withdrawn from Australia, Canada, Europe and a few other countries following reports of suspected adverse liver reactions.</p> <p>Methods</p> <p>This randomised, double-blind study enrolled 309 patients (aged greater than or equal to 50 years) with primary OA across 51 centres in Europe. Patients were randomly allocated to receive either lumiracoxib 400 mg od (four times the recommended dose in OA) (<it>n </it>= 154) or rofecoxib 25 mg od (<it>n </it>= 155). The study was conducted for 6 weeks and assessments were performed at Weeks 3 and 6. The primary safety measures were the incidence of predefined GI adverse events (AEs) and peripheral oedema. The secondary safety measures included effect of treatment on the mean sitting systolic and diastolic blood pressure (msSBP and msDBP). Tolerability of lumiracoxib 400 mg was assessed by the incidence of AEs.</p> <p>Results</p> <p>Lumiracoxib and rofecoxib displayed similar GI safety profiles with no statistically significant difference in predefined GI AEs between the two groups (43.5% <it>vs</it>. 37.4%, respectively). The incidence and severity of individual predefined GI AEs was comparable between the two groups. The incidence of peripheral oedema was low and identical in both the groups (<it>n </it>= 9, 5.8%). Only one patient in the lumiracoxib group and three patients in the rofecoxib group had a moderate or severe event. At Week 6 there was a significantly lower msSBP and msDBP in the lumiracoxib group compared to the rofecoxib group (<it>p </it>< 0.05). A similar percentage of patients in both groups showed an improvement in target joint pain and disease activity. The tolerability profile was similar in both the treatment groups.</p> <p>Conclusion</p> <p>Lumiracoxib 400 mg od (four times the recommended dose in OA) provided a comparable GI safety profile to rofecoxib 25 mg od (therapeutic dose). However, lumiracoxib was associated with a significantly better BP profile as compared to rofecoxib.</p> <p>Trial registration number -</p> <p>NCT00637949</p