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The controlled delivery of selenium nanoparticles (Se‐NPs) is promising for bone cancer treatment due to their dual benefits in bone regeneration and tumor inhibition, yet achieving an optimal dosing regimen remains challenging. Natural mesoporous biosilica (BS) beads have shown promise for drug delivery due to their microporous structure. This study explores incorporating BS beads into collagen‐chitosan (Coll‐CS) scaffolds, known for bone repair, to control Se‐NP delivery. Two approaches are compared: loading Se‐NPs into BS beads before integrating them into Coll‐CS scaffolds versus directly loading Se‐NPs into Coll‐CS scaffolds. The scaffold properties, Se release kinetics, cytocompatibility, and effects on mesenchymal stem cells (MSCs) and prostate cancer cells (LNCaP) are evaluated. BS bead‐loaded scaffolds provide controlled Se‐NP release and enhanced mechanical properties compared to directly loaded scaffolds. Higher Se‐NP concentrations in BS‐loaded scaffolds effectively promote MSC osteogenic differentiation and mineralisation while inhibiting LNCaP cell viability. In contrast, low Se‐NP concentrations not only induce early osteogenic differentiation but also promote cancer cell proliferation, underscoring the need for optimal Se‐NP concentration and release. These findings suggest that BS bead‐loaded Coll‐CS scaffolds are a promising strategy for controlled Se‐NP delivery, addressing the dual challenges of bone formation and cancer recurrence prevention in bone cancer treatment. [ABSTRACT FROM AUTHOR]

Stem cells are an essential consideration in the fields of tissue engineering and regenerative medicine. Understanding how nanoengineered biomaterials and mesenchymal stem cells (MSCs) interact is crucial for their role in bone regeneration. Taking advantage of the structural stability of selenium nanoparticles (Se-NPs) and biological properties of natural polymers, Se-NPs-functionalized, injectable, thermoresponsive hydrogels with an interconnected molecular structure were prepared to identify their role in the osteogenic differentiation of different types of mesenchymal stem cells. Further, comprehensive characterization of their structural and biological properties was performed. The results showed that the hydrogels undergo a sol to gel transition with the help of β-glycerophosphate, while functionalization with Se-NPs significantly enhances their biological response through stabilizing their polymeric structure by forming Se–O covalent bonds. Further results suggest that Se-NPs enhance the differentiation of MSCs toward osteogenic lineage in both the 2D as well as 3D. We demonstrated that the Se-NPs-functionalized hydrogels could enhance the differentiation of osteoporotic bone-derived MSCs. We also focused on specific cell surface marker expression (CD105, CD90, CD73, CD45, CD34) based on the exposure of healthy rats' bone marrow-derived stem cells (BMSCs) to the Se-NP-functionalized hydrogels. This study provides essential evidence for pre-clinical/clinical applications, highlighting the potential of the nanoengineered biocompatible elastic hydrogels for bone regeneration in diseased bone. [ABSTRACT FROM AUTHOR]

Using feminist, queer and postcolonial theories, this paper analyzes the public commentary and anxious concern about child-welfare in a recent lesbian teacher sex scandal in Vancouver, Canada, involving Jean Robertson. Arguing that the public and professional uproar is not really about child-protectionism so much as it is about the place of white teacher lesbianism in school culture, I ask new questions about how the regulation of teenage sexuality operates to secure heterosexual bifurcations of gender in the school. The idea of the innocent, white "girl" child is, in this paper, shown to anchor a public and professional worry about the proliferation of queer teenage identifications in the school. Using Judith Butler's formulation of the heterosexual matrix, Lee Edelman's conceptualization of reproductive futurity, Judith Halberstam's investigation of queer time and space, and Mikko Tuhkanen's postcolonial reading of lesbian sexuality in popular film, I underscore societal-based upset about white teacher lesbianism. I argue that the teacher sex scandals in North America are driven by an unspoken societal upset about identifications and desires inhospitable to binary gender positions and heteronormative futures. (Contains 1 note.)

This paper examines the social construction of white, female, spinster teacher personality profiles in the first half of the 20th century. Focusing on the psychological, medical, and psychoanalytic literature, I provide an overview of how white unmarried female teacher personalities were understood in order to provide a historical context for present day queer and transgender identities in North American schools. I identify four main personality profiles of the female teacher in educational historiography which were informed by Freudian psychoanalysis: the masculinity complex; moral masochism; altruistic surrender; and the tyrannical disciplinarian. I conclude that spinster teacher personality profiles can be read as queer and gender-variant and that such readings shed light on gender and sexual regulation in education historiography. (Contains 2 notes.)

In this essay, the author first describes the cultural ethos of the Federation of Women Teachers' Associations of Ontario (FWTAO), with its primary commitment to the never-married teacher. She then traces the declining status of the single, female teacher in the postwar period. Coupled with this decline is an emphasis placed on the importance of marriage and motherhood by the educational community. Second, the author examines the postwar sociological and psychological literature to show how traditional gender roles and heterosexual identity cultures were both regulatory and normative. The importance placed on heterosexual adjustment by educational administrators became intricately tied to the worry about female homosexuality, masculine identified, and independent women. This essay also argues that married women teachers attained the professional stature originally held by single female teachers. The newly formed allegiance to the marriageable and heterosexually attractive woman (whether married or unmarried) caused difficulty for single females wanting to pursue administrative positions. The call to embrace a heterosexual ideal of beauty worked as an obstacle to tenure and to upward career mobility for female teachers who could not or would not adhere to these regulatory ideals. (Contains 135 footnotes.)