HIV-1 infection of microglial cells in a reconstituted humanized mouse model and identification of compounds that selectively reverse HIV latency.

Most studies of HIV latency focus on the peripheral population of resting memory T cells, but the brain also contains a distinct reservoir of HIV-infected cells in microglia, perivascular macrophages, and astrocytes. Studying HIV in the brain has been challenging, since live cells are difficult to recover from autopsy samples and primate models of SIV infection utilize viruses that are more myeloid-tropic than HIV due to the expression of Vpx. Development of a realistic small animal model would greatly advance studies of this important reservoir and permit definitive studies of HIV latency. When radiation or busulfan-conditioned, immune-deficient NSG mice are transplanted with human hematopoietic stem cells, human cells from the bone marrow enter the brain and differentiate to express microglia-specific markers. After infection with replication competent HIV, virus was detected in these bone marrow-derived human microglia. Studies of HIV latency in this model would be greatly enhanced by the development of compounds that can selectively reverse HIV latency in microglial cells. Our studies have identified members of the CoREST repression complex as key regulators of HIV latency in microglia in both rat and human microglial cell lines. The monoamine oxidase (MAO) and potential CoREST inhibitor, phenelzine, which is brain penetrant, was able to stimulate HIV production in human microglial cell lines and human glial cells recovered from the brains of HIV-infected humanized mice. The humanized mice we have developed therefore show great promise as a model system for the development of strategies aimed at defining and reducing the CNS reservoir

Damage in porous media due to salt crystallization

We investigate the origins of salt damage in sandstones for the two most common salts: sodium chloride and sulfate. The results show that the observed difference in damage between the two salts is directly related to the kinetics of crystallization and the interfacial properties of the salt solutions and crystals with respect to the stone. We show that, for sodium sulfate, the existence of hydrated and anhydrous crystals and specifically their dissolution and crystallization kinetics are responsible for the damage. Using magnetic resonance imaging and optical microscopy we show that when water imbibes sodium sulfate contaminated sandstones, followed by drying at room temperature, large damage occurs in regions where pores are fully filled with salts. After partial dissolution, anhydrous sodium sulfate salt present in these regions gives rise to a very rapid growth of the hydrated phase of sulfate in the form of clusters that form on or close to the remaining anhydrous microcrystals. The rapid growth of these clusters generates stresses in excess of the tensile strength of the stone leading to the damage. Sodium chloride only forms anhydrous crystals that consequently do not cause damage in the experiments

The lipoatrophic caveolin-1 deficient mouse model reveals autophagy in mature adipocytes

Adipose tissue lipoatrophy caused by caveolin gene deletion in mice is not linked to defective adipocyte differentiation. We show that adipose tissue development cannot be rescued by endothelial specific caveolin-1 re-expression, indicating primordial role of caveolin in mature adipocytes. Partial or total caveolin deficiency in adipocytes induced broad protein expression defects, including but not limited to previously described downregulation of insulin receptor. Global alterations in protein turnover, and accelerated degradation of long-lived proteins were found in caveolin-deficient adipocytes. Lipidation of endogenous LC3 autophagy marker and distribution of GFP-LC3 into aggregates demonstrated activated autophagy in the absence of caveolin-1 in adipocytes. Furthermore, electron microscopy revealed autophagic vacuoles in caveolin-1 deficient but not control adipocytes. Surprisingly, significant levels of lipidated LC3-II were found around lipid droplets of normal adipocytes, maintained in nutrient-rich conditions or isolated from fed mice, which do not display autophagy. Altogether, these data indicate that caveolin deficiency induce autophagy in adipocytes, a feature that is not a physiological response to fasting in normal fat cells. This likely resulted from defective insulin and lipolytic responses that converge in chronic nutrient shortage in adipocytes lacking caveolin-1. This is the first report of a pathological situation with autophagy as an adaptative response to adipocyte failure

Impact of COVID-19 on mental health in Bhutan: a way forward for action

The coronavirus disease 2019 (COVID-19) pandemic continues to impact mental health and wellbeing globally. There is a lack of scientific documentation highlighting the mental health impact of COVID-19 in Bhutan. We present the mental health burdens and control measures taken, and suggest ways to further strengthen mental health services in Bhutan. During the pandemic, a rise in depression and anxiety had been reported in Bhutan. Depression rose from an average prevalence of 9 per 10,000 between 2011 and 2019 to 16 per 10,000 in 2020 and 32 per 10,000 in 2021. Similarly, anxiety rose from an average prevalence of 18 per 10,000, to 29 per 10,000 in 2020, and 55 per 10,000 in 2021. Psychological impacts related to isolation due to lockdowns, economic losses, and poor coping abilities were associated with negative outcomes. Stigma and discrimination towards mental health disorders discouraged mentally distressed people from seeking care. In response to increased demand, Bhutan's government initiated a range of interventions including home delivery of medicines and tele-counselling to people in need of urgent mental health care. Mental health care in Bhutan can be further improved through investment in services and human resources, and decentralization of services to the community

Effective suckling in relation to naked maternal-infant body contact in the first hour of life: an observation study

Background Best practice guidelines to promote breastfeeding suggest that (i) mothers hold their babies in naked body contact immediately after birth, (ii) babies remain undisturbed for at least one hour and (iii) breastfeeding assistance be offered during this period. Few studies have closely observed the implementation of these guidelines in practice. We sought to evaluate these practices on suckling achievement within the first hour after birth. Methods Observations of seventy-eight mother-baby dyads recorded newborn feeding behaviours, the help received by mothers and birthing room practices each minute, for sixty minutes. Results Duration of naked body contact between mothers and their newborn babies varied widely from 1 to 60 minutes, as did commencement of suckling (range = 10 to 60 minutes). Naked maternal-infant body contact immediately after birth, uninterrupted for at least thirty minutes did not predict effective suckling within the first hour of birth. Newborns were four times more likely to sustain deep rhythmical suckling when their chin made contact with their mother’s breast as they approached the nipple (OR 3.8; CI 1.03 - 14) and if their mothers had given birth previously (OR 6.7; CI 1.35 - 33). Infants who had any naso-oropharyngeal suctioning administered at birth were six times less likely to suckle effectively (OR .176; CI .04 - .9). Conclusion Effective suckling within the first hour of life was associated with a collection of practices including infants positioned so their chin can instinctively nudge the underside of their mother’s breast as they approach to grasp the nipple and attach to suckle. The best type of assistance provided in the birthing room that enables newborns to sustain an effective latch was paying attention to newborn feeding behaviours and not administering naso-oropharyngeal suction routinely

Localised angiosarcomas: The identification of prognostic factors and analysis of treatment impact. A retrospective analysis from the French Sarcoma Group (GSF/GETO)

BackgroundAngiosarcomas represent less than 2% of all adult soft tissue sarcomas. Prognostic factors and the role of (neo-) adjuvant treatments in the management of localised angiosarcomas require further investigation. Methods We have conducted a retrospective multicenter study (June 1980 to October 2009) of 107 patients with localised angiosarcomas. All of the cases were centrally reviewed by a certified pathologist. Univariate and multivariate analyses were conducted to identify independent poor prognostic factors (PF). Overall survival (OS) and Local Recurrence-Free Survival (LRFS) were estimated using the Kaplan–Meier method. The effect of treatments was explored using the Cox model after adjusting for the PF. Results The median age was 71 years. 22.4% and 62.6% developed an angiosarcoma in pre-existing lymphoedema and within irradiated tissue respectively. The median OS, LRFS and Disease Recurrence-Free Survival (DRFS) were 38.8, 27 and 36.1 months, respectively. In multivariate analysis, the following parameters influenced the OS: lymphoedema (Hazard ratio (HR) = 2.0) and size >5 cm (HR = 1.5). After adjustment to these PF, R0 margins was the only treatment parameter that improving the OS (HR = 0.2). In the multivariate analysis, the LRFS was influenced by an age >70 (HR = 1.8) and pre-existing lymphoedema (HR = 2.0). After adjustment for these PF, R0 margins (HR = 0.5) and adjuvant radiotherapy (HR = 0.3) improved the LRFS. Conclusions Our results suggest the following points: (i) pre-existing lymphoedema, tumour size and age >70 are probably the major prognostic factors in patients with localised angiosarcomas; (ii) the achievement of R0 margins is probably of major importance for improving the patient outcome and (iii) adjuvant radiotherapy probably decreased the risk of local recurrence

Combination of mTORC1/2 inhibitor vistusertib plus fulvestrant in vitro and in vivo targets oestrogen receptor-positive endocrine-resistant breast cancer.

BACKGROUND:Endocrine therapies are still the main strategy for the treatment of oestrogen receptor-positive (ER+) breast cancers (BC), but resistance remains problematic. Cross-talk between ER and PI3K/AKT/mTORC has been associated with ligand-independent transcription of ER. We have previously reported the anti-proliferative effects of the combination of everolimus (an mTORC1 inhibitor) with endocrine therapy in resistance models, but potential routes of escape via AKT signalling can lead to resistance; therefore, the use of dual mTORC1/2 inhibitors has met with significant interest. METHODS:To address this, we tested the effect of vistusertib, a dual mTORC1 and mTORC2 inhibitor, in a panel of endocrine-resistant and endocrine-sensitive ER+ BC cell lines, with varying PTEN, PIK3CA and ESR1 mutation status. End-points included proliferation, cell signalling, cell cycle and effect on ER-mediated transcription. Two patient-derived xenografts (PDX) modelling endocrine resistance were used to assess the efficacy of vistusertib, fulvestrant or the combination on tumour progression, and biomarker studies were conducted using immunohistochemistry and RNA-seq technologies. RESULTS:Vistusertib caused a dose-dependent decrease in proliferation of all the cell lines tested and reduced abundance of mTORC1, mTORC2 and cell cycle markers, but caused an increase in abundance of EGFR, IGF1R and ERBB3 in a context-dependent manner. ER-mediated transcription showed minimal effect of vistusertib. Combined therapy of vistusertib with fulvestrant showed synergy in two ER+ PDX models of resistance to endocrine therapy and delayed tumour progression after cessation of therapy. CONCLUSIONS:These data support the notion that models of acquired endocrine resistance may have a different sensitivity to mTOR inhibitor/endocrine therapy combinations