Transmission Electron Microscopy of Bone.

Electron microscopic analysis of mineralized tissues like bone and dentin is essential for understanding of cell-cell/cell-matrix interactions, and the three-dimensional organization of these tissues. This chapter describes a few methods to process mineralized tissues obtained from different sources for ultrastructural analysis by transmission electron microscopy.

A gendered users' perspective on decentralized primary health services in rural Tanzania.

Since the 1990s, Tanzania has been implementing health sector reforms including decentralization of primary healthcare services to districts and users. The impact of the reforms on the access, quality and appropriateness of primary healthcare services from the viewpoint of users is, however, not clearly documented. This article draws on a gendered users' perspective to address the question of whether the delivery of gender-sensitive primary health services has improved after the reforms.

Women's autonomy and husbands' involvement in maternal health care in Nepal.

Both increasing women's autonomy and increasing husbands' involvement in maternal health care are promising strategies to enhance maternal health care utilization. However, these two may be at odds with each other insofar as autonomous women may not seek their husband's involvement, and involved husbands may limit women's autonomy. This study assessed the relationship between women's autonomy and husbands' involvement in maternal health care.

Socio-Cultural Dispositions and Wellbeing of the Women Left Behind: A Case of Migrant Households in Nepal.

The concept of wellbeing is gaining popularity in the study of quality of life and cultural significance of living. The paper aims to contribute to our understanding of objective and subjective wellbeing by exploring the perceptions of women left behind by out-migrating husbands on their quality of life in a transnational social field. The paper uses both qualitative and quantitative research methods.

Transmission electron microscopy of bone.

This chapter describes procedures to process mineralized tissues obtained from different sources for transmission electron microscopy (TEM). Methods for fixation, resin embedding, staining of semi-thin sections and ultrathin sections are presented. In addition, attention will be paid to processing of cultured bone explants for TEM analysis.

The significance of gathering wild orchid tubers for orphan household livelihoods in a context of HIV/AIDS in Tanzania.

We investigated the role of gathering and selling the edible tubers of wild orchids by children orphaned by AIDS as one of their livelihood strategies, through a household survey administered to 152 households in three villages in the Southern Highlands of Tanzania during 2006 and 2007. Additionally, several household heads were selected as case studies and subjected to an in-depth life-history interview. Overall, most households in the study villages were very poor.

Cementum and dentin in hypophosphatasia.

Hypophosphatasia (HPP) often leads to premature loss of deciduous teeth, due to disturbed cementum formation. We addressed the question to what extent cementum and dentin are similarly affected. To this end, we compared teeth from children with HPP with those from matched controls and analyzed them microscopically and chemically.

Inhibition of molar eruption and root elongation in MT1-MMP-deficient mice.

To study whether eruption of teeth and root growth require remodeling of collagen in the peridental tissues, we studied molar development in mice deficient in MT1-MMP, an enzyme essential for remodeling of soft tissue-hard tissue interfaces. The lower jaws of deficient mice and their wildtype littermates were subjected to stereologic analysis. It was shown that in deficient animals, eruption and root elongation were severely inhibited, signifying a role of the enzyme in these developmental processes.

On the role of MT1-MMP, a matrix metalloproteinase essential to collagen remodeling, in murine molar eruption and root growth.

Although the connective tissues of the periodontium are subject to a high turnover rate, no conclusive evidence has yet emerged that periodontal collagen turnover is essential for the eruption of teeth or for root elongation. These processes were studied in mice deficient in MT1-MMP, a membrane type matrix metalloproteinase essential for remodeling of soft tissue-hard tissue interfaces. Mandibular first molars of deficient mice and their wild-type littermates were subjected to stereological analysis in order to assess root length, eruption and the volume density of phagocytosed collagen in periodontal ligament fibroblasts.

Type VI collagen is associated with microfibrils and oxytalan fibers in the extracellular matrix of periodontium, mesenterium and periosteum.

Type VI collagen was immunolocalized in several soft connective tissues at the light and electron microscopic level. Positive labeling was found in all tissues examined, periodontal ligament, gingiva, mesenterium and periosteum. The labeled structures could be divided into 2 categories: microfibrils intermingling with collagen fibrils, and those that formed bundles (oxytalan fibres and elastin-associated microfibrils).

Formation of reparative acellular extrinsic fiber cementum in relation to implant materials installed in rat periodontium.

The aim of the present study was to determine the nature of the cells associated with the formation of reparative acellular extrinsic fiber cementum (AEFC). Calcifying collagen membranes, hydroxyapatite particles and/or non-resorbable ePTFE membranes were implanted in lesions made in the periodontium of the rat mandibular incisor. The incisor was prevented from erupting further, and the animals were killed after 1-8 wk.

Type VI collagen is phagocytosed by fibroblasts and digested in the lysosomal apparatus: involvement of collagenase, serine proteinases and lysosomal enzymes.

Type VI collagen is present in most connective tissues, where it is considered to play a crucial role in the attachment of cells to the extracellular matrix and/or in the three-dimensional organization of the collagen meshwork. Although some information is available on its formation, the mechanisms involved in its degradation are not understood. Here, we present evidence for lysosomal digestion of type VI collagen by fibroblasts of periosteal explants.

Proteoglycans in cementum- and enamel-related predentin of young mouse incisors as visualized by cuprolinic blue.

In rodent incisors, dentin associated with cementum (root-analogue dentin) appears to differ considerably from that associated with enamel (crown-analogue dentin), both with respect to the composition of certain matrix components and the mineral. Since it is not known whether these dentin portions also differ with respect to their proteoglycans, the morphological appearance and spatial distribution of these components was studied in predentin by employing cuprolinic blue, a dye selective for proteoglycans. Lower incisors of five-day-old mice were stained with the dye and processed for electron microscopic examination.

Degradation of collagen in the bone-resorbing compartment underlying the osteoclast involves both cysteine-proteinases and matrix metalloproteinases.

The site of action of cysteine-proteinases (CPs) and matrix metalloproteinases (MMPs) in the degradation of bone collagen by osteoclasts was investigated by evaluating the effects of the CP-inhibitor trans-epoxy-succinyl-L-leucylamido (4-guanidino)-butane (E-64) and the MMP-inhibitor N-(3-N-benzyloxycarbonyl amino-1-R-carboxypropyl)-L-leucyl-O-methyl-L-tyrosine N-methylamide (Cl-1) in an in vitro model system of PTH-stimulated mouse calvaria. In the presence of each of the two inhibitors a large area of collagen free of mineral crystallites was seen adjacent to the ruffled border of the osteoclasts. Following a culture period of 24 h this area proved to be about 10 times larger in inhibitor-treated explants than in controls.

Root-analogue versus crown-analogue dentin: a radioautographic and ultrastructural investigation of the mouse incisor.

The present paper reports on differences between the root- and crown-analogue dentin portions of the continuously growing mouse incisor. Conventional light microscopy and radioautography were used to study dentin formation and the uptake of [3H]-proline and [3H]-serine. It was found that, although the dentin apposition rate along the crown-analogue part (covered by enamel) equalled or slightly exceeded that along the root-analogue part (covered by cementum), the processing of predentin into dentin was considerably faster in the root aspect.

Effects of 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) on the formation of dentin and the periodontal attachment apparatus in the mouse.

The effects of the bisphosphonate HEBP on dentin formation and the structural relationship between the dentin and the developing periodontal attachment apparatus have been studied in the continuously growing mouse incisor. It was observed that HEBP (in doses greater than or equal to 8 mg P/kg b.w/day) not only inhibited the deposition of mineral crystallites in newly formed dentin matrix, but also entirely prevented the formation of a layer of acellular root cementum.