The anatomy of the pelvic plexus in female cadavers: implications for retroperitoneal nerve-sparing surgery.

Background: The inferior hypogastric plexus (IHP) is a crucial structure for female continence and sexual function. A nerve-sparing approach should be pursued to reduce the risk of pelvic plexus damage during retroperitoneal pelvic surgery.

Objectives: To analyse the relationship between the female IHP and several pelvic anatomical landmarks.

Anatomic Cartography of the Hypogastric Nerves and Surgical Insights for Autonomic Preservation during Radical Pelvic Procedures.

Study Objective: To clarify the relationship of hypogastric nerves (HNs) with several pelvic anatomic landmarks and to assess any anatomic differences between the 2 sides of the pelvis, both in cadaveric and in vivo dissections.

Design: Prospective observational study.

Setting: An anatomic theater for cadaveric dissections and a university hospital for in vivo laparoscopy.

Bone morphogenetic protein signaling regulates postnatal hair follicle differentiation and cycling.

Hair follicle morphogenesis and cycling were examined in transgenic mice that overexpress the bone morphogenetic protein (BMP) inhibitor Noggin under the control of the neuron-specific enolase promoter. The Noggin transgene was misexpressed in the proximal portion of the hair follicle, primarily the matrix cells, apart from the usual expression in neurons. Transgene expression appeared only after induction of both the primary (tylotrich) and secondary (nontylotrich) pelage hair follicles had already occurred, thus allowing examination of the role of BMP signaling in follicles that had been induced normally in the presence of BMPs.

Distinctive expression of filaggrin and trichohyalin during various pathways of epithelial differentiation.

Filaggrin and trichohyalin are keratin intermediate filament-associated proteins, and are primarily expressed in the granular cells of the epidermis and in the inner root sheath cells of the hair follicles, respectively. These two proteins are, however, occasionally co-expressed in some tissues. To gain more insights into the mechanisms for expression and processing of (pro)filaggrin and trichohyalin during various pathways of epithelial differentiation, we compared their localization by double immunostaining techniques in normal and psoriatic epidermis, tongue filiform papillae and cultured human epidermal keratinocytes.

Trichohyalin expression in skin tumors: retrieval of trichohyalin antigenicity in tissues by microwave irradiation.

Background: The antitrichohyalin antibody AE 15 is effective for identifying the cell lineage that undergoes the pathway of inner root sheath-type differentiation. Unfortunately, the AE 15 does not react with trichohyalin in tissue that is formalin-fixed and embedded in paraffin according to routine procedures.

Methods: We attempted to retrieve the trichohyalin antigenicity in formalin-fixed, paraffin-embedded biopsy specimens that included normal skin as well as skin tumors such as trichofolliculoma and pilotricoma.

Expression of keratohyalin-trichohyalin hybrid granules in molluscum contagiosum.

Background: Recently, in the filiform papillae epithelium of mouse dorsal tongue, we showed the presence of hybrid granules in which filaggrin and trichohyalin were both present, but physically segregated. Further, trichohyalin was also detected in scattered granular cells of a number of hyperplastic skin diseases.

Methods: The epidermis infected with molluscum contagiosum virus (MCV) was studied by conventional electron microscopy in conjunction with light and electron-microscopic immunohistochemistry, using both antifilaggrin and antitrichohyalin antibodies as probes.

Altered distribution of keratinization markers in epidermolytic hyperkeratosis.

Epidermolytic hyperkeratosis (EH) is a genetic disorder of keratins associated with epidermal differentiation. Affected individuals carry gene mutations for conserved sequences of keratins K1 or K10. The structural alterations of tonofilaments in EH seem to be a direct consequence of the keratin gene mutations.

Existence of trichohyalin-keratohyalin hybrid granules: co-localization of two major intermediate filament-associated proteins in non-follicular epithelia.

Trichohyalin is a protein of relatively high molecular weight (approximately 200 kDa), associated with intermediate filaments, that was for many years thought to be expressed only in the inner root sheath and medulla of the hair follicle. We show here, however, that this protein is expressed in association with (pro)filaggrin in the granular layer of many non-follicular, keratinizing, stratified epithelia which also express keratins K6/K16, including those of the filiform papillae of dorsal tongue epithelia. In this epithelium, which elaborates morphologically heterogeneous keratohyalin granules in its upper cell layers, trichohyalin forms hybrid granules with filaggrin, the major intermediate filament associated protein found in keratohyalin granules, which is normally expressed in advanced epidermal differentiation.

Abnormal lamellar granules in harlequin ichthyosis.

Lamellar granules are specialized lipid-rich organelles present in epidermal granular cells. They fuse with the apical cell surface and discharge their contents into the intercellular space forming lamellar sheets. It was previously shown by electron microscopy that lamellar granules in biopsies of infants affected with harlequin ichthyosis are either absent or abnormal and no intercellular lamellae could be detected.

Keratohyalin, trichohyalin and keratohyalin-trichohyalin hybrid granules: an overview.

Filaggrin and trichohyalin are the two major intermediate filament associated proteins which interact with keratin filaments in the skin. These two proteins initially accumulate in cytoplasmic granules called keratohyalin or trichohyalin granules which provide prominent morphological hallmarks of differentiation in the epidermis and the inner root sheath of hair follicles, respectively. The contents of each of these granules are modified and subsequently released into the cytoplasm of the fully mature cells where they function in the role of aggregating keratin filament bundles.

Interaction of trichohyalin with intermediate filaments: three immunologically defined stages of trichohyalin maturation.

"Trichohyalin" is a 220-kD protein found in trichohyalin granules that are present as major differentiation products in the medulla and inner root sheath cells of human hair follicles. It was unclear whether this protein served as an intermediate filament precursor in the inner root sheath or as an intermediate-filament-associated (matrix) protein. We have produced a panel of monoclonal antibodies (AE15-17) to this protein and used them to trace its fate during inner root sheath differentiation.

Association of a basic 25K protein with membrane coating granules of human epidermis.

Keratinocytes of the upper granular layers contain unique round-to-oval granules, 100-500 nm in diameter, in their peripheral cytoplasm. These granules (known as membrane coating granules [MCG], or lamellar granules) fuse with the apical cell surface of uppermost granular cells and discharge their contents into the intercellular space, where they are believed to play a role in establishing the permeability barrier of the epidermis and possibly in regulating the orderly desquamation of terminally differentiated keratinocytes. Using two monoclonal antibodies originally prepared against hair follicle antigens, we have identified a 25K epidermal protein in association with both MCG-like granules in the peripheral cytoplasm of granular cells as well as MCG-derived intercellular material.

Acidic and basic hair/nail ("hard") keratins: their colocalization in upper cortical and cuticle cells of the human hair follicle and their relationship to "soft" keratins.

Although numerous hair proteins have been studied biochemically and many have been sequenced, relatively little is known about their in situ distribution and differential expression in the hair follicle. To study this problem, we have prepared several mouse monoclonal antibodies that recognize different classes of human hair proteins. Our AE14 antibody recognizes a group of 10-25K hair proteins which most likely corresponds to the high sulfur proteins, our AE12 and AE13 antibodies define a doublet of 44K/46K proteins which are relatively acidic and correspond to the type I low sulfur keratins, and our previously described AE3 antibody recognizes a triplet of 56K/59K/60K proteins which are relatively basic and correspond to the type II low sulfur keratins.

Intermediate filament expression and lifespan potential in human somatic cell hybrids.

Limited lifespan human diploid fibroblast cells have been fused with the HeLa derived cell line HEB 7A which possesses transformed growth characteristics and unlimited division potential. HEB 7A expresses keratin intermediate filaments, while the fibroblast cells express only vimentin intermediate filaments. Independently arising clones of hybrids were examined for the presence of keratin by indirect immunofluorescence.

Clonal variations in keratin. Intermediate filament expression by human somatic cell hybrids.

The intermediate filament composition of differentiated vertebrate cells provides a stable phenotype which appears to be specifically regulated in each cell type. In order to analyse the regulation of intermediate filament expression we have constructed human somatic cell hybrids from the fusion of the HeLa-derived cell line HEB7A and a normal human diploid fibroblast, GM2291. These parental cells differ with respect to the presence or absence of keratin intermediate filaments.

Altered keratin biosynthesis follows inhibition of scale morphogenesis by hydrocortisone.

Hydrocortisone, administered onto the chorioallantoic membrane (CAM) of 7- to 10-day-old chick embryos, inhibits scale development, in a dose- and stage-dependent manner. The response is also region specific in that hydrocortisone treatment, at a specific dose and time, will completely block scutellate and interstitial scale development while leaving other scale types unaffected. Using histological, biochemical, and immunofluorescence techniques, we have shown that inhibition of scutellate scale morphogenesis prevents the subsequent formation of a beta stratum and alters expression of the alpha keratins.

Avian scale development. X. Dermal induction of tissue-specific keratins in extraembryonic ectoderm.

Epidermal-dermal tissue interactions regulate morphogenesis and tissue-specific keratinization of avian skin appendages. The morphogenesis of scutate scales differs from that of reticulate scales, and the keratin polypeptides of their epidermal surfaces are also different. Do the inductive cues which initiate morphogenesis of these scales also establish the tissue-specific keratin patterns of the epidermis, or does the control of tissue-specific keratinization occur at later stages of development? Unlike feathers, scutate and reticulate scales can be easily separated into their epidermal and dermal components late in development when the major events of morphogenesis have been completed and keratinization will begin.

Rearrangement of the keratin cytoskeleton after combined treatment with microtubule and microfilament inhibitors.

In addition to containing microtubule and microfilament systems, vertebrate epithelial cells contain an elaborate keratin intermediate-filament cytoskeleton. Little is known about its structural organization or function. Using indirect immunofluorescence microscopy with an antikeratin antiserum probe, we found that destabilization of microtubules and microfilaments with cytostatic drugs induces significant alterations in the cytoskeletal organization of keratin filaments in HeLa and fetal mouse epidermal cells.

Drug-induced alterations of cytokeratin organization in cultured epithelial cells.

The distribution of keratin intermediate filaments, previously considered static in organization and imperturbable by conventional drugs used to alter the structure and organization of the cytoskeleton, can be altered significantly by treatment with colchicine and cytochalasin D. The loss of microfilaments and microtubules converts the keratin cytoskeleton from a branching, even distribution to a series of starlike structures whose filaments are maintained by multiple membrane attachment sites. These findings provide a means for manipulating cytokeratin organization to investigate the role of keratins in cytoskeletal structure and function.