Pregnancies in women with Turner syndrome: a retrospective multicentre UK study.

OBJECTIVE: To determine the characteristics and outcomes of pregnancy in women with Turner syndrome. DESIGN: Retrospective 20-year cohort study (2000-20). SETTING: Sixteen tertiary referral maternity units in the UK. POPULATION OR SAMPLE: A total of 81 women with Turner syndrome who became pregnant. METHODS: Retrospective chart analysis. MAIN OUTCOME MEASURES: Mode of conception, pregnancy outcomes. RESULTS: We obtained data on 127 pregnancies in 81 women with a Turner phenotype. All non-spontaneous pregnancies (54/127; 42.5%) were by egg donation. Only 9/31 (29%) pregnancies in women with karyotype 45,X were spontaneous, compared with 53/66 (80.3%) pregnancies in women with mosaic karyotype 45,X/46,XX (P < 0.0001). Women with mosaic karyotype 45,X/46,XX were younger at first pregnancy by 5.5-8.5 years compared with other Turner syndrome karyotype groups (P < 0.001), and more likely to have a spontaneous menarche (75.8% versus 50% or less, P = 0.008). There were 17 miscarriages, three terminations of pregnancy, two stillbirths and 105 live births. Two women had aortic dissection (2.5%); both were 45,X karyotype with bicuspid aortic valves and ovum donation pregnancies, one died. Another woman had an aortic root replacement within 6 months of delivery. Ten of 106 (9.4%) births with gestational age data were preterm and 22/96 (22.9%) singleton infants with birthweight/gestational age data weighed less than the tenth centile. The caesarean section rate was 72/107 (67.3%). In only 73/127 (57.4%) pregnancies was there documentation of cardiovascular imaging within the 24 months before conceiving. CONCLUSIONS: Pregnancy in women with Turner syndrome is associated with major maternal cardiovascular risks; these women deserve thorough cardiovascular assessment and counselling before assisted or spontaneous pregnancy managed by a specialist team. TWEETABLE ABSTRACT: Pregnancy in women with Turner syndrome is associated with an increased risk of aortic dissection.

Mesenchymal stem/stromal cell-based therapies for severe viral pneumonia: therapeutic potential and challenges.

Severe viral pneumonia is a significant cause of morbidity and mortality globally, whether due to outbreaks of endemic viruses, periodic viral epidemics, or the rarer but devastating global viral pandemics. While limited anti-viral therapies exist, there is a paucity of direct therapies to directly attenuate viral pneumonia-induced lung injury, and management therefore remains largely supportive. Mesenchymal stromal/stem cells (MSCs) are receiving considerable attention as a cytotherapeutic for viral pneumonia. Several properties of MSCs position them as a promising therapeutic strategy for viral pneumonia-induced lung injury as demonstrated in pre-clinical studies in relevant models. More recently, early phase clinical studies have demonstrated a reassuring safety profile of these cells. These investigations have taken on an added importance and urgency during the COVID-19 pandemic, with multiple trials in progress across the globe. In parallel with clinical translation, strategies are being investigated to enhance the therapeutic potential of these cells in vivo, with different MSC tissue sources, specific cellular products including cell-free options, and strategies to 'licence' or 'pre-activate' these cells, all being explored. This review will assess the therapeutic potential of MSC-based therapies for severe viral pneumonia. It will describe the aetiology and epidemiology of severe viral pneumonia, describe current therapeutic approaches, and examine the data suggesting therapeutic potential of MSCs for severe viral pneumonia in pre-clinical and clinical studies. The challenges and opportunities for MSC-based therapies will then be considered.

The influence of macrophages on mesenchymal stromal cell therapy: passive or aggressive agents?

Mesenchymal stromal cells (MSC) have emerged as promising cell therapies for multiple conditions based on demonstrations of their potent immunomodulatory and regenerative capacities in models of inflammatory disease. Understanding the effects of MSC on T cells has dominated the majority of work carried out in this field to date; recently, however, a number of studies have shown that the therapeutic effect of MSC requires the presence of macrophages. It is timely to review the mechanisms and manner by which MSC modulate macrophage populations in order to design more effective MSC therapies and clinical studies. A complex cross-talk exists through which MSC and macrophages communicate, a communication that is not controlled exclusively by MSC. Here, we examine the evidence that suggests that MSC not only respond to inflammatory macrophages and adjust their secretome accordingly, but also that macrophages respond to encounters with MSC, creating a feedback loop which contributes to the immune regulation observed following MSC therapy. Future studies examining the effects of MSC on macrophages should consider the antagonistic role that macrophages play in this exchange.

Cross-sectional biomonitoring study of pesticide exposures in Queensland, Australia, using pooled urine samples.

A range of pesticides are available in Australia for use in agricultural and domestic settings to control pests, including organophosphate and pyrethroid insecticides, herbicides, and insect repellents, such as N,N-diethyl-meta-toluamide (DEET). The aim of this study was to provide a cost-effective preliminary assessment of background exposure to a range of pesticides among a convenience sample of Australian residents. De-identified urine specimens stratified by age and sex were obtained from a community-based pathology laboratory and pooled (n = 24 pools of 100 specimens). Concentrations of urinary pesticide biomarkers were quantified using solid-phase extraction coupled with isotope dilution high-performance liquid chromatography-tandem mass spectrometry. Geometric mean biomarker concentrations ranged from <0.1 to 36.8 ng/mL for organophosphate insecticides, <0.1 to 5.5 ng/mL for pyrethroid insecticides, and <0.1 to 8.51 ng/mL for all other biomarkers with the exception of the DEET metabolite 3-diethylcarbamoyl benzoic acid (4.23 to 850 ng/mL). We observed no association between age and concentration for most biomarkers measured but noted a "U-shaped" trend for five organophosphate metabolites, with the highest concentrations observed in the youngest and oldest age strata, perhaps related to age-specific differences in behavior or physiology. The fact that concentrations of specific and non-specific metabolites of the organophosphate insecticide chlorpyrifos were higher than reported in USA and Canada may relate to differences in registered applications among countries. Additional biomonitoring programs of the general population and focusing on vulnerable populations would improve the exposure assessment and the monitoring of temporal exposure trends as usage patterns of pesticide products in Australia change over time.

Evaluation of red blood cell distribution width in cats with hypertrophic cardiomyopathy.

BACKGROUND: Red blood cell distribution width (RDW) is a measurement of variability in circulating erythrocytes size, and has recently been shown to correlate with prognosis in a variety of human diseases, including acute and chronic heart failure. OBJECTIVES: To determine if RDW differs between healthy controls, cats with hypertrophic cardiomyopathy (HCM) without congestive heart failure (CHF) and cats with HCM and CHF, and to evaluate whether RDW values at presentation can provide useful prognostic information in cats with HCM. ANIMALS: Retrospective single-centre study. Seventy-three cats diagnosed with HCM by echocardiography and 30 healthy controls presented to a veterinary teaching hospital between October 2006 and April 2013 were included. Physical examination, haematology and echocardiographic data obtained on one single visit were retrospectively reviewed and compared between three groups: controls, cats with HCM without CHF, and cats with HCM and CHF. Outcome data were obtained from clinical records or referring veterinarians. Univariable and multivariable survival analyses were performed. RESULTS: Red blood cell distribution width was significantly greater in cats with HCM and CHF compared with cats with HCM without CHF, and the controls. It was also significantly associated with cardiac mortality in univariable survival analysis, and this association remained significant in multivariable survival analysis after controlling for the effect of CHF, left atrial size, left ventricular systolic function, haematocrit and pro-thrombotic state. CONCLUSIONS: A higher RDW may be seen in cats with CHF and is an independent predictor of cardiac death in cats with HCM without concurrent non-cardiac-related illness.

Human mesenchymal stem cells suppress donor CD4(+) T cell proliferation and reduce pathology in a humanized mouse model of acute graft-versus-host disease.

Acute graft-versus-host disease (aGVHD) is a life-threatening complication following allogeneic haematopoietic stem cell transplantation (HSCT), occurring in up to 30-50% of patients who receive human leucocyte antigen (HLA)-matched sibling transplants. Current therapies for steroid refractory aGVHD are limited, with the prognosis of patients suboptimal. Mesenchymal stem or stromal cells (MSC), a heterogeneous cell population present in many tissues, display potent immunomodulatory abilities. Autologous and allogeneic ex-vivo expanded human MSC have been utilized to treat aGVHD with promising results, but the mechanisms of therapeutic action remain unclear. Here a robust humanized mouse model of aGVHD based on delivery of human peripheral blood mononuclear cells (PBMC) to non-obese diabetic (NOD)-severe combined immunodeficient (SCID) interleukin (IL)-2rγ(null) (NSG) mice was developed that allowed the exploration of the role of MSC in cell therapy. MSC therapy resulted in the reduction of liver and gut pathology and significantly increased survival. Protection was dependent upon the timing of MSC therapy, with conventional MSC proving effective only after delayed administration. In contrast, interferon (IFN)-γ-stimulated MSC were effective when delivered with PBMC. The beneficial effect of MSC therapy in this model was not due to the inhibition of donor PBMC chimerism, as CD45(+) and T cells engrafted successfully in this model. MSC therapy did not induce donor T cell anergy, FoxP3(+) T regulatory cells or cause PBMC apoptosis in this model; however, it was associated with the direct inhibition of donor CD4(+) T cell proliferation and reduction of human tumour necrosis factor-α in serum.

Identification of Sarcocystis capracanis in cerebrospinal fluid from sheep with neurological disease.

Protozoal merozoites were identified in the cerebrospinal fluid of two sheep with neurological disease in the UK. Polymerase chain reaction (PCR) identified the merozoites as Sarcocystis capracanis, a common protozoal pathogen of goats. This is the first report of this species infecting sheep and may represent an aberrant infection with sheep acting as dead end hosts, or alternatively could indicate that sheep are able to act as intermediate hosts for S. capracanis, widening the previously reported host range of this pathogen. It is possible that S. capracanis is a previously unrecognised cause of ovine protozoal meningoencephalitis (OPM) in the UK.

First detection of 'Candidatus Mycoplasma haemolamae' infection in alpacas in England.

This is the first report of detection of Candidatus Mycoplasma haemolamae in alpacas in England. The primary case occurred in a three year-old male alpaca in the south-east of England which presented with a history of progressive weight loss, lethargy, swelling of the scrotum and pale mucous membranes. Blood smear examination revealed a moderate, regenerative anaemia, with numerous small basophilic coccoid structures consistent with Candidatus M haemolamae. To confirm the presence of Candidatus M haemolamae, a portion of the 16S rDNA gene was amplified and analysed by denaturing gradient gel electrophoresis (DGGE). 16S rDNA gene sequencing showed a 99.8 per cent homology with Candidatus M haemolamae sequences deposited in GenBank. Subsequently, a cross-sectional study was carried out to investigate the presence of Candidatus M haemolamae infection in the alpaca herd from which the primary case was detected (n=131). Blood smear examinations and PCR with DGGE were used and compared with a species-specific PCR. The prevalence of infection when PCR positive results were combined was 29 per cent. A substantial agreement between the PCR/DGGE and the species-specific PCR was found (κ=0.86). A significant association was also found between age and infection (P=0.04) while no significant association was found with sex or origin.

Physiological condition differentially affects the behavior and survival of two populations of sockeye salmon during their freshwater spawning migration.

Recently, a segment of the Adams-Shuswap sockeye salmon (Oncorhynchus nerka) population initiated freshwater migration several weeks earlier than historically recorded, resulting in high mortality rates. The comigrating Chilko population maintained their historic river entry timing and did not experience elevated mortality. To test the hypothesis that population-specific differences in physiological condition would differentially influence behavior and survival when exposed to fisheries capture stress, we physiologically sampled individuals from both populations at the onset of the freshwater phase of their reproductive migration and tracked the remainder of their migrations using radio telemetry. Adams-Shuswap individuals had slower migration rates and were less likely to reach natal subwatersheds relative to Chilko individuals. Metabolic and osmoregulatory impairment was related to mortality for Adams-Shuswap individuals but not for Chilko individuals. Similarly, physiological condition correlated with migration rate for Adams-Shuswap but not Chilko fish. Survival to natal subwatersheds was 1.9 times higher for Chilko relative to Adams-Shuswap, a result that did not emerge until individuals approached natal subwatersheds several days after the stressor was applied. We conclude that physiological condition differentially affects the behavior and survival of these two populations, which may be a consequence of the early-entry phenomenon by a segment of the Adams-Shuswap population.

Attenuated Bordetella pertussis vaccine strain BPZE1 modulates allergen-induced immunity and prevents allergic pulmonary pathology in a murine model.

BACKGROUND: Virulent Bordetella pertussis, the causative agent of whooping cough, exacerbates allergic airway inflammation in a murine model of ovalbumin (OVA) sensitization. A live genetically attenuated B. pertussis mucosal vaccine, BPZE1, has been developed that evokes full protection against virulent challenge in mice but the effect of this attenuated strain on the development of allergic responses is unknown. OBJECTIVE: To assess the influence of attenuated B. pertussis BPZE1 on OVA priming in a murine model of allergic airway inflammation. METHODS: Mice were challenged with virulent or attenuated strains of B. pertussis, and sensitized to allergen (OVA) at the peak of bacterial carriage. Subsequently, airway pathology, local inflammation and OVA-specific immunity were examined. RESULTS: In contrast to virulent B. pertussis, live BPZE1 did not exacerbate but reduced the airway pathology associated with allergen sensitization. BPZE1 immunization before allergen sensitization did not have an adjuvant effect on allergen specific IgE but resulted in a statistically significant decrease in airway inflammation in tissue and bronchoalveolar lavage fluid. BPZE1 significantly reduced the levels of OVA-driven IL-4, IL-5 and IL-13 but induced a significant increase in IFN-gamma in response to OVA re-stimulation. CONCLUSIONS: These data demonstrate that, unlike virulent strains, the candidate attenuated B. pertussis vaccine BPZE1 does not exacerbate allergen-driven airway pathology. BPZE1 may represent an attractive T-helper type 1 promoting vaccine candidate for eradication of whooping cough that is unlikely to promote atopic disease.

Cell contact, prostaglandin E(2) and transforming growth factor beta 1 play non-redundant roles in human mesenchymal stem cell induction of CD4+CD25(High) forkhead box P3+ regulatory T cells.

Adult human mesenchymal stromal or stem cells (MSC) can differentiate into a variety of cell types and are candidate cellular therapeutics in regenerative medicine. Surprisingly, these cells also display multiple potent immunomodulatory capabilities, including allosuppression, making allogeneic cell therapy a possibility. The exact mechanisms involved in regulatory T cell induction by allogeneic human MSC was examined, using purified CD4+ populations and well-characterized bone marrow-derived adult human MSC. Allogeneic MSC were shown to induce forkhead box P3 (FoxP3)+ and CD25+ mRNA and protein expression in CD4+ T cells. This phenomenon required direct contact between MSC and purified T cells, although cell contact was not required for MSC induction of FoxP3 expression in an unseparated mononuclear cell population. In addition, through use of antagonists and neutralizing antibodies, MSC-derived prostaglandins and transforming growth factor (TGF)-beta1 were shown to have a non-redundant role in the induction of CD4+CD25+FoxP3+ T cells. Purified CD4+CD25+ T cells induced by MSC co-culture expressed TGF-beta1 and were able to suppress alloantigen-driven proliferative responses in mixed lymphocyte reaction. These data clarify the mechanisms of human MSC-mediated allosuppression, supporting a sequential process of regulatory T cell induction involving direct MSC contact with CD4+ cells followed by both prostaglandin E(2) and TGF-beta1 expression. Overall, this study provides a rational basis for ongoing clinical studies involving allogeneic MSC.

Testosterone does not adversely affect fibrinogen or tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) levels in 46 men with chronic stable angina.

OBJECTIVE: In women, sex hormones cause increased morbidity and mortality in patients with coronary heart disease (CHD) and adversely affect the coagulation profile. We have studied the effect of physiological testosterone replacement therapy in men on coagulation factor expression, to determine if there is an increased risk of thrombosis. METHODS: Double-blind, randomized, placebo-controlled trial of testosterone in 46 men with chronic stable angina. Measurements of free, total and bioavailable testosterone, luteinising hormone (LH) and follicle-stimulating hormone (FSH), estradiol, plasminogen activator inhibitor-1 (PAI-1), fibrinogen, tissue plasminogen activator (tPA) and full blood count were made at 0, 6 and 14 weeks. RESULTS: Bioavailable testosterone levels were: 2.58 +/- 0.58 nmol/l at baseline, compared with 3.35 +/- 0.31 nmol/l at week 14 (P < 0.001) after treatment compared with 2.6 +/- 0.18 nmol/l and 2.44 +/- 0.18 nmol/l in the placebo group (P was not significant). There was no change in fibrinogen (3.03 +/- 0.18 g/l at baseline and 3.02 +/- 0.18 g/l at week 14, P = 0.24), tPA activity (26.77 +/- 4.9 Iu/ml and 25.67 +/- 4.4 Iu/ml, P = 0.88) or PAI-1 activity (0.49 +/- 0.85 Iu/ml and 0.36 +/- 0.06 Iu/ml, P = 0.16) with active treatment and no differences between the groups (at week 14, P value 0.98, 0.59 and 0.8 for fibrinogen, PAI-1 and tPA respectively). Haemoglobin concentration did not change over time, in the testosterone group (1.44 +/- 0.02 g/l and 1.45 +/- 0.02 g/l, P = 0.22). CONCLUSION: Physiological testosterone replacement does not adversely affect blood coagulation status.

Women in cardiology: a UK perspective.

Women are particularly under-represented in cardiology in the UK, even though women outnumber men in admissions to medical school. Could this disparity be detrimental to the specialty in this country?

Testosterone inhibits the prostaglandin F2alpha-mediated increase in intracellular calcium in A7r5 aortic smooth muscle cells: evidence of an antagonistic action upon store-operated calcium channels.

Testosterone-induced vasodilatation is proposed to contribute to the beneficial effects associated with testosterone replacement therapy in men with cardiovascular disease, and is postulated to occur via either direct calcium channel blockade, or through potassium channel activation via increased production of cyclic nucleotides. We utilised flow cytometry to investigate whether testosterone inhibits the increase in cellular fluorescence induced by prostaglandin F(2alpha) in A7r5 smooth muscle cells loaded with the calcium fluorescent probe indo-1-AM, and to study the cellular mechanisms involved. Two-minute incubation with testosterone (1 microM) significantly inhibited the change in cellular fluorescence in response to prostaglandin F(2alpha) (10 microM) (3.6+/-0.6 vs 7.6+/-1.0 arbitrary units, P=0.001). The change in cellular fluorescence in response to prostaglandin F(2alpha) (10 microM) was also significantly attenuated in the absence of extracellular calcium (3.6+/-0.3 vs 15.6+/-0.7 arbitrary units, P=0.0000002), and by a 2-min incubation with the store-operated calcium channel blocker SK&F 96365 (50 microM) (4.7+/-0.8 vs 8.1+/-0.4 arbitrary units, P=0.003). The response was insensitive to similar incubation with the voltage-operated calcium channel blockers verapamil (10 microM) (12.6+/-1.2 vs 11.9+/-0.2 arbitrary units, P=0.7) or nifedipine (10 microM) (13.9+/-1.3 vs 13.3+/-0.5 arbitrary units, P=0.7). Forskolin (1 microM) and sodium nitroprusside (100 microM) significantly increased the cellular concentration of cyclic adenosine monophosphate and cyclic guanosine monophosphate respectively, but testosterone (100 nM-100 microM) had no effect. These data indicate that the increase in intracellular calcium in response to prostaglandin F(2alpha) occurs primarily via extracellular calcium entry through store-operated calcium channels. Testosterone inhibits the response, suggesting an antagonistic action upon these channels.

Testosterone acts as a coronary vasodilator by a calcium antagonistic action.

T acts as a vasodilator in vitro and in vivo. Supplemental T therapy in humans with angina improves symptoms and reduces objective measures of ischemia. In left anterior descending coronary arteries taken from adult male Wistar rats, T abolishes 100+/-4.2% of calcium-dependent contraction induced by potassium chloride, 82.3+/-6.1% of the mostly calcium-dependent contraction induced by prostaglandin-F-2-alpha, but only 45.3+/-3.4% of the contraction induced by phorbol-12,13-dibutyrate (PDBu) in the presence of extracellular calcium, and 54.5+/-4.5% of the contraction induced by PDBu in the absence of extracellular calcium. These findings suggest that T is primarily inhibiting the calcium-dependent elements of vascular contraction.