A retrospective cross-sectional study: Fresh cycle endometrial thickness is a sensitive predictor of inadequate endometrial thickness in frozen embryo transfer cycles

BACKGROUND: The purpose of this study is to assess predictors of inadequate endometrial cavity thickness (ECT), defined as < 8 mm, in frozen embryo transfer (FET) cycles. METHODS: This is a retrospective cross-sectional study at an academic fertility center including 274 women who underwent their first endometrial preparation with estradiol for autologous FET in our center from 2001-2009. Multivariable logistic regression was performed to determine predictors of inadequate endometrial development in FET cycles. RESULTS: Neither age nor duration of estrogen supplementation were associated with FET endometrial thickness. Lower body mass index, nulliparity, previous operative hysteroscopy and thinner fresh cycle endometrial lining were associated with inadequate endometrial thickness in FET cycles. A maximum thickness of 11.5 mm in a fresh cycle was 80% sensitive and 70% specific for inadequate frozen cycle thickness. CONCLUSIONS: Previous fresh cycle endometrial cavity thickness is associated with subsequent FET cycle endometrial cavity thickness. Women with a fresh cycle thickness of 11.5 mm or less may require additional intervention to achieve adequate endometrial thickness in preparation for a frozen cycle

Variability in the practice of fertility preservation for patients with cancer

Fertility is important to women and men with cancer. While options for fertility preservation (FP) are available, knowledge regarding the medical application of FP is lacking. Therefore we examined FP practices for cancer patients among reproductive endocrinologists (REs). A 36 item survey was sent to board-certified REs. 98% of respondents reported counseling women with cancer about FP options. Oocyte and embryo cryopreservation were universally offered by these providers, but variability was noted in reported management of these cases-particularly for women with breast cancer. 86% of the respondents reported using letrozole during controlled ovarian stimulation (COS) in patients with estrogen receptor positive (ER+) breast cancer to minimize patient exposure to estrogen. 49% of respondents who reported using letrozole in COS for patients with ER+ breast cancer reported that they would also use letrozole in COS for women with ER negative breast cancer. Variability was also noted in the management of FP for men with cancer. 83% of participants reported counseling men about sperm banking with 22% recommending against banking for men previously exposed to chemotherapy. Overall, 79% of respondents reported knowledge of American Society for Clinical Oncology FP guidelines-knowledge that was associated with providers offering gonadal tissue cryopreservation (RR 1.82, 95% CI 1.14-2.90). These findings demonstrate that RE management of FP in cancer patients varies. Although some variability may be dictated by local resources, standardization of FP practices and communication with treating oncologists may help ensure consistent recommendations and outcomes for patients seeking FP

The cytosolic entry of diphtheria toxin catalytic domain requires a host cell cytosolic translocation factor complex

In vitro delivery of the diphtheria toxin catalytic (C) domain from the lumen of purified early endosomes to the external milieu requires the addition of both ATP and a cytosolic translocation factor (CTF) complex. Using the translocation of C-domain ADP-ribosyltransferase activity across the endosomal membrane as an assay, the CTF complex activity was 650–800-fold purified from human T cell and yeast extracts, respectively. The chaperonin heat shock protein (Hsp) 90 and thioredoxin reductase were identified by mass spectrometry sequencing in CTF complexes purified from both human T cell and yeast. Further analysis of the role played by these two proteins with specific inhibitors, both in the in vitro translocation assay and in intact cell toxicity assays, has demonstrated their essential role in the productive delivery of the C-domain from the lumen of early endosomes to the external milieu. These results confirm and extend earlier observations of diphtheria toxin C-domain unfolding and refolding that must occur before and after vesicle membrane translocation. In addition, results presented here demonstrate that thioredoxin reductase activity plays an essential role in the cytosolic release of the C-domain. Because analogous CTF complexes have been partially purified from mammalian and yeast cell extracts, results presented here suggest a common and fundamental mechanism for C-domain translocation across early endosomal membranes

Engineered Toxins “Zymoxins” Are Activated by the HCV NS3 Protease by Removal of an Inhibitory Protein Domain

The synthesis of inactive enzyme precursors, also known as “zymogens,” serves as a mechanism for regulating the execution of selected catalytic activities in a desirable time and/or site. Zymogens are usually activated by proteolytic cleavage. Many viruses encode proteases that execute key proteolytic steps of the viral life cycle. Here, we describe a proof of concept for a therapeutic approach to fighting viral infections through eradication of virally infected cells exclusively, thus limiting virus production and spread. Using the hepatitis C virus (HCV) as a model, we designed two HCV NS3 protease-activated “zymogenized” chimeric toxins (which we denote “zymoxins”). In these recombinant constructs, the bacterial and plant toxins diphtheria toxin A (DTA) and Ricin A chain (RTA), respectively, were fused to rationally designed inhibitor peptides/domains via an HCV NS3 protease-cleavable linker. The above toxins were then fused to the binding and translocation domains of Pseudomonas exotoxin A in order to enable translocation into the mammalian cells cytoplasm. We show that these toxins exhibit NS3 cleavage dependent increase in enzymatic activity upon NS3 protease cleavage in vitro. Moreover, a higher level of cytotoxicity was observed when zymoxins were applied to NS3 expressing cells or to HCV infected cells, demonstrating a potential therapeutic window. The increase in toxin activity correlated with NS3 protease activity in the treated cells, thus the therapeutic window was larger in cells expressing recombinant NS3 than in HCV infected cells. This suggests that the “zymoxin” approach may be most appropriate for application to life-threatening acute infections where much higher levels of the activating protease would be expected

The coloniality of infrastructure: Engineering, landscape and modernity in Recife

Geographical scholarship has, since the late 1990s, shown how infrastructure was central to the making of urban modernity and the metabolic transformation of socio-natures. Meanwhile, the work of Latin American scholars including Aníbal Quijano and Maria Lugones has focussed attention on the imbrications between modernity and coloniality, in particular through the international racial division of labour. Moving between these ideas, I argue that there is intellectual and political ground to be gained by specifically accounting for the coloniality of infrastructure, in both its material and epistemic dimensions. I ground the analysis in the history of Recife, Northeast of Brazil, analyzing the role of British engineering in the production of the city's landscape and infrastructure, and address the epistemic dimensions of the coloniality of infrastructural by exploring infrastructural spectacle in 1920s Recife. Finally, I explore how the coloniality of infrastructure directs our attention to race, labour and finance

Bacterial Toxins and the Nervous System: Neurotoxins and Multipotential Toxins Interacting with Neuronal Cells

Toxins are potent molecules used by various bacteria to interact with a host organism. Some of them specifically act on neuronal cells (clostridial neurotoxins) leading to characteristics neurological affections. But many other toxins are multifunctional and recognize a wider range of cell types including neuronal cells. Various enterotoxins interact with the enteric nervous system, for example by stimulating afferent neurons or inducing neurotransmitter release from enterochromaffin cells which result either in vomiting, in amplification of the diarrhea, or in intestinal inflammation process. Other toxins can pass the blood brain barrier and directly act on specific neurons

The racial division of nature: Making land in Recife

In this paper I analyse the making and unmaking of amphibious urban modernity in Recife in the Northeast of Brazil between 1920 and 1950. I argue that the transformation of the city was predicated on an absorptive and eradicative notion of whiteness that necessitated the creation of dry, enclosed land. The process of urban transformation proceeded not only through a racial division of space, but through a racial division of nature. Racialised groups, and the houses, marshlands, and mangroves where they lived were subject to eradication not only as spaces but as ecologies and landscapes. Brazilian racial thought in the period was fundamentally imbricated with ideas about nature. Histories of coloniality, indigeneity, enslavement, and escape meant that forests, wetness, and the spectre of commonly held land were understood as threats to whiteness and its self‐association with order, enclosure, purity, and dryness. To answer why the division between the wet and the dry was so important, and why whiteness needed dryness, I turn back to philosophical investigations of the foundational myth of Brazil. I argue that a peculiarly Brazilian philosophy of nature, which drew racial lines within nature itself, underpinned a familiar, if uncanny, white supremacy that ordered society along the material and symbolic contours of race. Under colonial modernity, this philosophy translated into a division of the pure – rational, cleansed, dry, modern, urban space – from the impure – muddy, fearful, tangled, forested landscape. Under the conditions of dependent capitalism, the process on which this racial division of nature relied was enclosure. Identifying the historical process of the racial division of nature is of particular significance in Brazil, given the still flowing undercurrents of racial oppression and environmental plunder