Non-synaptic dendritic spines in neocortex

A long-held assumption states that each dendritic spine in the cerebral cortex forms a synapse, although this issue has not been systematically investigated. We performed complete ultrastructural reconstructions of a large (n=144) population of identified spines in adult mouse neocortex finding that only 3.6% of the spines clearly lacked synapses. Nonsynaptic spines were small and had no clear head, resembling dendritic filopodia, and could represent a source of new synaptic connections in the adult cerebral cortex.     

Prevalence and susceptibility testing of new species of pseudallescheria and scedosporium in a collection of clinical mold isolates

The prevalence of new species of Pseudallescheria and Scedosporium in a collection of 46 clinical isolates was analyzed. Strain identification was done by morphological and molecular methods. Four Scedosporium aurantiacum isolates were detected among the panel of clinical strains. The susceptibility profile of S. aurantiacum was similar to that of Scedosporium apiospermum.     

Bone Microenvironment-Suppressed T Cells Increase Osteoclast Formation and Osteolytic Bone Metastases in Mice

Immunotherapies use components of the immune system, such as T cells, to fight cancer cells, and are changing cancer treatment, causing durable responses in some patients. Bone metastases are a debilitating complication in advanced breast and prostate cancer patients. Approved treatments fail to cure bone metastases or increase patient survival and it remains unclear whether immunotherapy could benefit patients. The bone microenvironment combines various immunosuppressive factors, and combined with T cell products could increase bone resorption fueling the vicious cycle of bone metastases. Using syngeneic mouse models, our study revealed that bone metastases from 4T1 breast cancer contain tumor-infiltrating lymphocyte (TILs) and their development is increased in normal mice compared to immunodeficient and T-cell depleted mice. This effect seemed caused by the TILs specifically in bone, because T-cell depletion increased 4T1 orthotopic tumors and did not affect bone metastases from RM-1 prostate cancer cells, which lack TILs. T cells increased osteoclast formation ex vivo and in vivo contributing to bone metastasis vicious cycle. This pro-osteoclastic effect is specific to unactivated T cells, because activated T cells, secreting interferon γ (IFNγ) and interleukin 4 (IL-4), actually suppressed osteoclastogenesis, which could benefit patients. However, non-activated T cells from bone metastases could not be activated in ex vivo cultures. 4T1 bone metastases were associated with an increase of functional polymorphonuclear and monocytic myeloid-derived suppressor cells (MDSCs), potent T-cell suppressors. Although effective in other models, sildenafil and zoledronic acid did not affect MDSCs in bone metastases. Seeking other therapeutic targets, we found that monocytic MDSCs are more potent suppressors than polymorphonuclear MDSCs, expressing programmed cell death receptor-1 ligand (PD-L1)⁺ in bone, which could trigger T-cell suppression because 70% express its receptor, programmed cell death receptor-1 (PD-1). Collectively, our findings identified a new mechanism by which suppressed T cells increase osteoclastogenesis and bone metastases. Our results also provide a rationale for using immunotherapy because T-cell activation would increase their anti-cancer and their anti-osteoclastic properties. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).     

Dietary Flavonoids Added to Pharmacological Antihypertensive Therapy are Effective in Improving Blood Pressure

Epidemiological studies have suggested that the daily intake of flavonoids is associated with a decreased risk of developing cardiovascular disease. Our purpose was to evaluate the effect of the addition of dietary flavonoids (DF) to antihypertensive treatment (AHT), based on telmisartan (Tms) or captopril (Cpr), on blood pressure (BP), body mass index (BMI), waist/hip ratio, leptin, lipid profile and inflammation in hypertensive young patients. An open‐label, randomized, controlled trial was performed among 79 patients aged 20–55 years with grade I or grade II systemic arterial hypertension. The subjects were assigned to one of four groups for AHT plus DF during 6 months: Cpr (n = 14), Cpr + DF (n = 19), Tms (n = 25) and Tms + DF (n = 21). DF consisted of dark chocolate, dehydrated red apple and green tea in an infusion to obtain a daily dose of 425.8 ± 13.9 mg epicatechin equivalents. The BP and anthropometric parameters were measured every 2 weeks. Lipid profile, leptin and hsCRP were determined by standard methods. The combination AHT‐DF produced an additional and significant reduction in (i) SBP/DBP of ?5/?4 mmHg, being ?7/?5 for Cpr + DF and ?4/?3 for Tms + DF; (ii) triglyceride levels (?30.6%) versus AHT alone (?9.6%); and (iii) leptin: Cpr + DF versus Tms + DF (p < 0.005). Finally, C‐reactive protein plasma levels were reduced significantly in all groups independently of the applied treatment. We conclude that the addition of flavonoids to pharmacological antihypertensive therapy shows additional benefits on BP, lipid profile, leptin, obesity and inflammation.     

Shrunken pore syndrome,preeclampsia, and markers of NO metabolism in pregnant women during the first trimester

Shrunken pore syndrome (SPS) is a condition that manifests itself as the decreased renal clearance of low-molecular-weight proteins but normal clearance of creatinine. Pregnant women with evidence of SPS during the first trimester have an increased risk of developing preeclampsia (PE). The nitric oxide (NO) metabolism markers arginine and ADMA, especially their ratio (Arg/ADMA), are recognized markers of endothelial dysfunction. The aim of this nested case–control study was to establish first-trimester reference intervals (RI) for markers of NO metabolism and to study these markers in women with evidence of SPS at the end of the first trimester. Seventy-four women were stratified in the first trimester according to evidence of SPS (SPS?+?or SPS–) and the occurrence of PE during subsequent pregnancy (PE?+?or PE–), as follows: SPS–/PE–, SPS+/PE–, SPS–/PE+, and SPS+/PE+. RIs were determined according to the CLSI EP28-A3c guidelines. Serum Arg and ADMA levels were analyzed. The Arg and ADMA concentrations did not differ among the four groups. However, women in the SPS+/PE?+?group had a significantly lower Arg/ADMA ratio than those in the other 3 groups (p?=?.02). In conclusion, we defined the first-trimester RI of Arg, ADMA and the Arg/ADMA ratio as markers of NO metabolism. Our results suggest that SPS in the first trimester predicts a pathophysiological hallmark of subsequent PE, i.e. lower NO production leading to increased vessel tone. Early identification of women at risk for later PE could lead to adaptive prophylactic interventions, such as supplementation with Arg or an NO-donor drug in order to mitigate the risk of developing PE.     

Primary cilia regulate hippocampal neurogenesis by mediating sonic hedgehog signaling

Primary cilia are present on mammalian neurons and glia, but their function is largely unknown. We generated conditional homozygous mutant mice for a gene we termed Stumpy. Mutants lack cilia and have conspicuous abnormalities in postnatally developing brain regions, including a hypoplasic hippocampus characterized by a primary deficiency in neural stem cells known as astrocyte-like neural precursors (ALNPs). Previous studies suggested that primary cilia mediate sonic hedgehog (Shh) signaling. Here, we find that loss of ALNP cilia leads to abrogated Shh activity, increased cell cycle exit, and morphological abnormalities in ALNPs. Processing of Gli3, a mediator of Shh signaling, is also altered in the absence of cilia. Further, key mediators of the Shh pathway localize to ALNP cilia. Thus, selective targeting of Shh machinery to primary cilia confers to ALNPs the ability to differentially respond to Shh mitogenic signals compared to neighboring cells. Our data suggest these organelles are cellular “antennae” critically required to modulate ALNP behavior.     

Perfluorooctanoic acid disrupts gap junction intercellular communication and induces reactive oxygen species formation and apoptosis in mouse ovaries

Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acid family of compounds. Due to the presence of strong carbon–fluorine bonds, it is practically nonbiodegradable and highly persistent in the environment. PFOA has been detected in the follicular fluid of women, and positively associated with reduced fecundability and infertility. However, there are no reports concerning the experimental evaluation of PFOA on oocyte toxicity in mammals. The aim of the present study was to determine if PFOA is able to induce oxidative stress in fetal ovaries and cause apoptosis in oocytes in vitro. In addition, since inhibition of the gap junction intercellular communication (GJIC) by PFOA has been demonstrated in liver cells in vivo and in vitro, the effect of PFOA on the GJIC between the oocyte and its supportive cumulus cells was studied. Results show that PFOA induced oocyte apoptosis and necrosis in vitro (medium lethal concentration, LC₅₀ = 112.8 μM), as evaluated with Annexin‐V‐Alexa 508 in combination with BOBO‐1 staining. Reactive oxygen species (ROS) levels, as assessed by DCFH‐DA, increased significantly in fetal ovaries exposed to ¼ LC₅₀ (28.2 μM, a noncytotoxic and relevant occupational exposure concentration) and LC₅₀ PFOA ex vivo. This perfluorinated compound also caused the blockage of GJIC in cumulus cells‐oocyte complexes (COCs) obtained from female mice exposed in vivo, as evaluated by calcein transfer from cumulus cells to the oocyte. The ability of PFOA of disrupting the GJIC in COCs, generating ROS in the fetal ovary and causing apoptosis and necrosis in mammal's oocytes, might account for the reported association between increasing maternal plasma concentrations of PFOA with reduced fertility in women.     

Cerebral vein thrombosis in patients with Philadelphia‐negative myeloproliferative neoplasms An European Leukemia Net study

To investigate the characteristics and clinical course of cerebral vein thrombosis (CVT) in patients with myeloproliferative neoplasms (MPN) we compared 48 patients with MPN and CVT (group MPN‐CVT) to 87 with MPN and other venous thrombosis (group MPN‐VT) and 178 with MPN and no thrombosis (group MPN‐NoT) matched by sex, age at diagnosis of MPN (±5 years) and type of MPN. The study population was identified among 5,500 patients with MPN, from January 1982 to June 2013. Thrombophilia abnormalities were significantly more prevalent in the MPN‐CVT and MPN‐VT than in MPN‐NoT group (P = 0.015), as well as the JAK2 V617F mutation in patients with essential thrombocythemia (P = 0.059). Compared to MPN‐VT, MPN‐CVT patients had a higher rate of recurrent thrombosis (42% vs. 25%, P = 0.049) despite a shorter median follow‐up period (6.1 vs. 10.3 years, P = 0.019), a higher long‐term antithrombotic (94% vs. 84%, P = 0.099) and a similar cytoreductive treatment (79% vs. 70%, P = 0.311). The incidence of recurrent thrombosis was double in MPN‐CVT than in MPN‐VT group (8.8% and 4.2% patient‐years, P = 0.022), and CVT and unprovoked event were the only predictive variables in a multivariate model including also sex, blood count, thrombophilia, cytoreductive, and antithrombotic treatment (HR 1.97, 95%CI 1.05–3.72 and 2.09, 1.09–4.00, respectively). Am. J. Hematol. 89:E200–E205, 2014. © 2014 Wiley Periodicals, Inc.